Predictors and Association With Clinical Outcomes of the Changes in Exercise Capacity After Transcatheter Aortic Valve Replacement.

PubMed

Abdul-Jawad Altisent, Omar; Puri, Rishi; Regueiro, Ander; Chamandi, Chekrallah; Rodriguez-Gabella, Tania; Del Trigo, Maria; Campelo-Parada, Francisco; Couture, Thomas; Marsal, Josep Ramon; Côté, Mélanie; Paradis, Jean-Michel; DeLarochellière, Robert; Doyle, Daniel; Mohammadi, Siamak; Dumont, Eric; Rodés-Cabau, Josep

2017-08-15

At present, there are no objective data specifically examining the clinical impact of variations in exercise capacity post-transcatheter aortic valve replacement (TAVR). We describe the changes in exercise capacity between baseline and 6 months post-TAVR, and ascertain factors associated with and clinical implications of a lack of improvement in exercise capacity post-TAVR. A total of 305 patients (mean age, 79±9 years; 44% men; Society of Thoracic Surgeons predicted risk mortality score, 6.7±4.2%) undergoing TAVR completed both baseline and follow-up exercise capacity assessments at 6 months post-TAVR. Exercise capacity was evaluated by the 6-minute walk test (6MWT). Clinical outcomes were compared between patients displaying greater than (n=152; improving group) versus less than (n=153; nonimproving group) the median percentage change in distance walked between baseline and 6-month follow-up examinations. The primary outcome measure was clinical event rates, measured from the 6-month post-TAVR period onward. Further dichotomization according to baseline 6MWT distance (less than versus more than median walking distance, or slow walker versus fast walker) was also assessed. The mean overall distances walked pre- and post-TAVR (6 months post-TAVR) were 204±119 and 263±116 m, respectively (Δ6MWT=60±106 m), with 219 (72%) patients demonstrating an increase in their walking distance (median percentage increase of the entire population was 20% [interquartile range, 0%-80%]). Factors independently correlated with reduced exercise capacity improvement included a range of baseline clinical characteristics (older age, female sex, chronic obstructive pulmonary disease; P <0.05 for all), periprocedural major or life-threatening bleeding ( P =0.009) and new-onset anemia at 6 months post-TAVR ( P =0.009). Failure to improve the 6MWT distance by at least 20% was independently associated with all-cause mortality ( P =0.002) and cardiovascular death or rehospitalization for cardiovascular causes ( P =0.001). Baseline slow walkers who were able to improve the 6MWT distance presented with significantly better outcomes than nonimprovers ( P =0.01 for all-cause mortality; P =0.001 for cardiovascular end point). Approximately one-third of patients undergoing TAVR did not improve their exercise capacity postprocedure. The lack of functional improvement post-TAVR was predicted by a mix of baseline and periprocedural factors translating into poorer clinical outcomes. These results suggest that systematically implementing exercise capacity assessment pre- and post-TAVR may help to improve patient risk stratification. © 2017 American Heart Association, Inc.

Prognostic capacity of a clinically indicated exercise test for cardiovascular mortality is enhanced by combined analysis of exercise capacity, heart rate recovery and T-wave alternans.

PubMed

Minkkinen, Mikko; Nieminen, Tuomo; Verrier, Richard L; Leino, Johanna; Lehtimäki, Terho; Viik, Jari; Lehtinen, Rami; Nikus, Kjell; Kööbi, Tiit; Turjanmaa, Väinö; Kähönen, Mika

2015-09-01

Exercise capacity, heart rate recovery and T-wave alternans are independent predictors of cardiovascular mortality. We tested whether these parameters contain supplementary prognostic information. A total of 3609 consecutive patients (2157 men) referred for a routine, clinically indicated bicycle exercise test were enrolled in the Finnish Cardiovascular Study (FINCAVAS). Exercise capacity was measured in metabolic equivalents, heart rate recovery as the decrease in heart rate from maximum to one minute post-exercise, and T-wave alternans by time-domain Modified Moving Average method. During 57-month median follow-up (interquartile range 35-78 months), 96 patients died of cardiovascular causes (primary endpoint) and 233 from any cause. All three parameters were independent predictors of cardiovascular mortality when analysed as continuous variables. Adding metabolic equivalents (p < 0.001), heart rate recovery (p = 0.002) or T-wave alternans (p = 0.01) to the linear model improved its predictive power for cardiovascular mortality. The combination of low exercise capacity (<6 metabolic equivalents), reduced heart rate recovery (≤12 beats/min) and elevated T-wave alternans (≥60 μV) yielded the highest hazard ratio for cardiovascular mortality of 16.5 (95% confidence interval 4.0-67.7, p < 0.001). Harrell's C index was 0.719 (confidence interval 0.665-0.772) for cardiovascular mortality with previously defined cutpoints (<8 units for metabolic equivalents, ≤18 beats/min for heart rate recovery and ≥60 μV for T-wave alternans). The prognostic capacity of the clinical exercise test is enhanced by combined analysis of exercise capacity, heart rate recovery and T-wave alternans. © The European Society of Cardiology 2014.

Low Cardiorespiratory Fitness is Partially Linked to Ventilatory Factors in Obese Adolescents.

PubMed

Mendelson, Monique; Michallet, Anne-Sophie; Tonini, Julia; Favre-Juvin, Anne; Guinot, Michel; Wuyam, Bernard; Flore, Patrice

2016-02-01

To examine the role of ventilatory constraint on cardiorespiratory fitness in obese adolescents. Thirty obese adolescents performed a maximal incremental cycling exercise and were divided into 2 groups based on maximal oxygen uptake (VO2peak): those presenting low (L; n = 15; VO2peak: 72.9 ± 8.6% predicted) or normal (N; n = 15; VO2peak: 113.6 ± 19.2% predicted) cardiorespiratory fitness. Both were compared with a group of healthy controls (C; n = 20; VO2peak: 103.1 ± 11.2% predicted). Ventilatory responses were explored using the flow volume loop method. Cardiorespiratory fitness (VO2peak, in % predicted) was lower in L compared with C and N and was moderately associated with the percent predicted forced vital capacity (FVC) (r = .52; p < .05) in L. At peak exercise, end inspiratory point was lower in L compared with N and C (77.4 ± 8.1, 86.4 ± 7.7, and 89.9 ± 7.6% FVC in L, N, and C, respectively; p < .05), suggesting an increased risk of ventilatory constraint in L, although at peak exercise this difference could be attributed to the lower maximal ventilation in L. Forced vital capacity and ventilatory strategy to incremental exercise slightly differed between N and L. These results suggest a modest participation of ventilatory factors to exercise intolerance.

Are there sex differences in the capillary blood volume and diffusing capacity response to exercise?

PubMed

Bouwsema, Melissa M; Tedjasaputra, Vincent; Stickland, Michael K

2017-03-01

Previous work suggests that women may exhibit a greater respiratory limitation in exercise compared with height-matched men. Diffusion capacity (Dl CO ) increases with incremental exercise, and the smaller lungs of women may limit membrane diffusing capacity (Dm) and pulmonary capillary blood volume (Vc) in response to the increased oxygen demand. We hypothesized that women would have lower Dl CO , Dl CO relative to cardiac output (Dl CO /Q̇), Dm, Vc, and pulmonary transit time, secondary to lower Vc at peak exercise. Sixteen women (112 ± 12% predicted relative V̇o 2peak ) and sixteen men (118 ± 22% predicted relative V̇o 2peak ) were matched for height and weight. Hemoglobin-corrected diffusing capacity (Dl CO ), Vc, and Dm were determined via the multiple-[Formula: see text] Dl CO technique at rest and during incremental exercise up to 90% of V̇o 2peak Both groups increased Dl CO , Vc, and Dm with exercise intensity, but women had 20% lower Dl CO ( P < 0.001), 18% lower Vc ( P = 0.002), and 22% lower Dm ( P < 0.001) compared with men across all workloads, and neither group exhibited a plateau in Vc. When expressed relative to alveolar volume (Va), the between-sex difference was eliminated. The drop in Dl CO /Q̇ was proportionally less in women than men, and mean pulmonary transit time did not drop below 0.3 s in either group. Women demonstrate consistently lower Dl CO , Vc, and Dm compared with height-matched men during exercise; however, these differences disappear with correction for lung size. These results suggest that after differences in lung volume are accounted for there is no intrinsic sex difference in the Dl CO , Vc, or Dm response to exercise. NEW & NOTEWORTHY Women demonstrate lower diffusing capacity-to-cardiac output ratio (Dl CO /Q̇), pulmonary capillary blood volume (Vc), and membrane diffusing capacity (Dm) compared with height-matched men during exercise. However, these differences disappear after correction for lung size. The drop in Dl CO /Q̇ was proportionally less in women, and pulmonary transit time did not drop below 0.3 s in either group. After differences in lung volume are accounted for, there is no intrinsic sex difference in Dl CO , Vc, or Dm response to exercise. Copyright © 2017 the American Physiological Society.

Role of the cardio-pulmonary exercise test and six-minute walking test in the evaluation of exercise performance in patients with late-onset Pompe disease.

PubMed

Crescimanno, G; Modica, R; Lo Mauro, R; Musumeci, O; Toscano, A; Marrone, O

2015-07-01

In patients with late-onset Pompe disease, we explored the role of the Cardiopulmonary Exercise Test (CPET) and the Six-Minute Walking Test (6MWT) in the assessment of exercise capacity and in the evaluation of the effects of enzyme replacement therapy (ERT). Eight patients affected by late-onset Pompe disease, followed up at the Centre for Neuromuscular Diseases and treated with ERT, underwent a baseline evaluation with a spirometry, a CPET and a 6MWT. Four of them were restudied after 36 months of treatment. Three patients showed a reduction in exercise capacity as evaluated by peak oxygen uptake (VO2) measured at the CPET and Distance Walked (DW) measured at the 6MWT (median % predicted: 67.1 [range 54.3-99.6] and 67.3 [56.6-82.6], respectively). Cardiac and respiratory limitations revealed by the CPET were correlated to peak VO2, but not to the DW. Nevertheless, percent of predicted values of peak VO2 and DW were strongly correlated (rho = 0.85, p = 0.006), and close to identity. In the longitudinal evaluation forced vital capacity decreased, while peak VO2 and DW showed a trend to a parallel improvement. We concluded that although only the CPET revealed causes of exercise limitation, which partially differed among patients, CPET and 6MWT showed a similar overall degree of exercise impairment. That held true in the longitudinal assessment during ERT, where both tests demonstrated similar small improvements, occurring despite deterioration in forced vital capacity. Copyright © 2015 Elsevier B.V. All rights reserved.

Cardiovascular testing in Fabry disease: exercise capacity reduction, chronotropic incompetence and improved anaerobic threshold after enzyme replacement.

PubMed

Lobo, T; Morgan, J; Bjorksten, A; Nicholls, K; Grigg, L; Centra, E; Becker, G

2008-06-01

The aim of this study was to document exercise capacity and serial electrocardiogram and echocardiograph findings in a cohort of Australian patients with Fabry disease, in relation to their history of enzyme replacement therapy (ERT). Fabry disease has multifactorial effects on the cardiovascular system. Most previous studies have focused on electrocardiographic and echocardiographic parameters. Exercise capacity can be used as an integrated measure of cardiovascular function and allows the effects of treatment to be monitored. A total of 38 patients (30 men and 8 women) with Fabry disease were monitored by 12-lead electrocardiograms every 6-12 months, and by annual standardized-protocol echocardiograms. Bicycle stress tests with VO(2) max measurement and once-only 6 minutes' walk tests were also carried out in subsets of patients whose general health status allowed testing. Seventy per cent of patients met electrocardiogram criteria for left ventricular hypertrophy. Left ventricular hypertrophy on echocardiograph was present in 64% of patients (80% of men). Exercise capacity was reduced in patients with Fabry disease compared with that predicted from normative population data. Mild improvement in anaerobic threshold was seen in the first year of ERT (14.1 +/- 3.0 to 15.8 +/- 3.0, P = 0.02), but no consistent further increase was seen beyond the first year. Most patients had resting bradycardia, with impaired ability to increase heart rate during exercise. Serial testing on ERT showed an improvement in anaerobic threshold but no significant change in VO(2) max. Male patients with Fabry disease were unable to attain predicted maximal heart rate on exercise or to achieve normal exercise levels. ERT was associated with a small improvement in anaerobic threshold over the first year.

Fit to Forgive: Effect of Mode of Exercise on Capacity to Override Grudges and Forgiveness

PubMed Central

Struthers, C. Ward; van Monsjou, Elizabeth; Ayoub, Mariam; Guilfoyle, Joshua R.

2017-01-01

Forgiveness is important for repairing relationships that have been damaged by transgressions. In this research we explored the notion that the mode of physical exercise that victims of transgressions engage in and their capacity to override grudges are important in the process of forgiveness. Two exploratory studies that varied in samples (community non-student adults, undergraduate students) and research methods (non-experimental, experimental) were used to test these predictions. Findings showed that, compared to anaerobic or no exercise, aerobic and flexibility exercise facilitated self-control over grudges and forgiveness (Studies 1 and 2), and self-control over grudges explained the relation between exercise and forgiveness (Study 2). Possible mechanisms for future research are discussed. PMID:28533758

Cigarette smoking decreases dynamic inspiratory capacity during maximal exercise in patients with type 2 diabetes.

PubMed

Kitahara, Yoshihiro; Hattori, Noboru; Yokoyama, Akihito; Yamane, Kiminori; Sekikawa, Kiyokazu; Inamizu, Tsutomu; Kohno, Nobuoki

2012-06-01

To investigate the influence of cigarette smoking on exercise capacity, respiratory responses and dynamic changes in lung volume during exercise in patients with type 2 diabetes. Forty-one men with type, 2 diabetes without cardiopulmonary disease were recruited and divided into 28 non-current smokers and 13 current smokers. All subjects received lung function tests and cardiopulmonary exercise testing using tracings of the flow-volume loop. Exercise capacity was compared using the percentage of predicted oxygen uptake at maximal workload (%VO2max). Respiratory variables and inspiratory capacity (IC) were compared between the two groups at rest and at 20%, 40%, 60%, 80% and 100% of maximum workload. Although there was no significant difference in lung function tests between the two groups, venous carboxyhemoglobin (CO-Hb) levels were significantly higher in current smokers. %VO2max was inversely correlated with CO-Hb levels. Changing patterns in respiratory rate, respiratory equivalent and IC were significantly different between the two groups. Current smokers had rapid breathing, a greater respiratory equivalent and a limited increase in IC during exercise. Cigarette smoking diminishes the increase in dynamic IC in patients with type 2 diabetes. As this effect of smoking on dynamic changes in lung volume will exacerbate dynamic hyperinflation in cases complicated by chronic obstructive pulmonary disease, physicians should consider smoking habits and lung function when evaluating exercise capacity in patients with type 2 diabetes.

Oxygen uptake kinetics and exercise capacity in children with cystic fibrosis.

PubMed

Fielding, Jeremy; Brantley, Lucy; Seigler, Nichole; McKie, Katie T; Davison, Gareth W; Harris, Ryan A

2015-07-01

Exercise capacity, an objective measure of exercise intolerance, is known to predict quality of life and mortality in cystic fibrosis (CF). The mechanisms for exercise intolerance in patients with cystic fibrosis (CF), however, have yet to be fully elucidated. Accordingly, this study sought to investigate oxygen uptake kinetics and the impact of fat-free mass (FFM) on exercise capacity in young patients with CF. 16 young patients with CF (age 13 ± 4 years; 10 female) and 15 matched controls (age 14 ± 3 years; nine female) participated. Pulmonary function and a maximal exercise test on a cycle ergometer using the Godfrey protocol were performed. Exercise capacity (VO2 peak), VO2 response time (VO2 RT), and functional VO2 gain (ΔVO2 /ΔWR) were all determined. Lung function was the only demographic parameter significantly lower (P < 0.05) in CF compared to controls. Exercise capacity was lower in CF (P < 0.014) only when VO2 peak was normalized for FFM (43.5 ± 7.7 vs. 50.6 ± 7.4 ml/kg-FFM/min) or expressed as % predicted (70.1 ± 14.3 vs. 85.4 ± 16.0%). The VO2 RT was slower (36.1 ± 15.1 vs. 25.0 ± 12.4 sec; P = 0.03) and the ΔVO2 /ΔWR slope was lower (8.4 ± 3 ml/min/watt vs. 10.1 ± 1.4 ml/min/watt; P = 0.02) in patients compared to controls, respectively. In conclusion, a delayed VO2 response time coupled with the lower functional VO2 gain (ΔVO2 /ΔWR) suggest that young patients with CF have impairment in oxygen transport and oxygen utilization by the muscles. These data in addition to differences in VO2 peak normalized for FFM provide some insight that muscle mass and muscle metabolism contribute to exercise intolerance in CF. © 2015 Wiley Periodicals, Inc.

Improving the Accuracy of Predicting Maximal Oxygen Consumption (VO2pk)

NASA Technical Reports Server (NTRS)

Downs, Meghan E.; Lee, Stuart M. C.; Ploutz-Snyder, Lori; Feiveson, Alan

2016-01-01

Maximal oxygen (VO2pk) is the maximum amount of oxygen that the body can use during intense exercise and is used for benchmarking endurance exercise capacity. The most accurate method to determineVO2pk requires continuous measurements of ventilation and gas exchange during an exercise test to maximal effort, which necessitates expensive equipment, a trained staff, and time to set-up the equipment. For astronauts, accurate VO2pk measures are important to assess mission critical task performance capabilities and to prescribe exercise intensities to optimize performance. Currently, astronauts perform submaximal exercise tests during flight to predict VO2pk; however, while submaximal VO2pk prediction equations provide reliable estimates of mean VO2pk for populations, they can be unacceptably inaccurate for a given individual. The error in current predictions and logistical limitations of measuring VO2pk, particularly during spaceflight, highlights the need for improved estimation methods.

External prognostic validations and comparisons of age- and gender-adjusted exercise capacity predictions.

PubMed

Kim, Esther S H; Ishwaran, Hemant; Blackstone, Eugene; Lauer, Michael S

2007-11-06

The purpose of this study was to externally validate the prognostic value of age- and gender-based nomograms and categorical definitions of impaired exercise capacity (EC). Exercise capacity predicts death, but its use in routine clinical practice is hampered by its close correlation with age and gender. For a median of 5 years, we followed 22,275 patients without known heart disease who underwent symptom-limited stress testing. Models for predicted or impaired EC were identified by literature search. Gender-specific multivariable proportional hazards models were constructed. Four methods were used to assess validity: Akaike Information Criterion (AIC), right-censored c-index in 100 out-of-bootstrap samples, the Nagelkerke Index R2, and calculation of calibration error in 100 bootstrap samples. There were 646 and 430 deaths in 13,098 men and 9,177 women, respectively. Of the 7 models tested in men, a model based on a Veterans Affairs cohort (predicted metabolic equivalents [METs] = 18 - [0.15 x age]) had the highest AIC and R2. In women, a model based on the St. James Take Heart Project (predicted METs = 14.7 - [0.13 x age]) performed best. Categorical definitions of fitness performed less well. Even after accounting for age and gender, there was still an important interaction with age, whereby predicted EC was a weaker predictor in older subjects (p for interaction <0.001 in men and 0.003 in women). Several methods describe EC accounting for age and gender-related differences, but their ability to predict mortality differ. Simple cutoff values fail to fully describe EC's strong predictive value.

Exercise Tolerance in Children With Early Onset Scoliosis: Growing Rod Treatment "Graduates".

PubMed

Jeans, Kelly A; Johnston, Charles E; Stevens, Wilshaw R; Tran, Dong-Phuong

2016-11-01

Prospectively enrolled early-onset scoliosis (EOS) patients undergoing growing rod treatment, who have had no surgery for >1 year and/or have received definitive fusion (growing rod "graduates"). To assess oxygen consumption during exercise and determine if a diminished conventional pulmonary function test (PFT) correlates with metabolic, pulmonary, and cardiovascular measures during exercise. Based on clinical impression and sequential PFT values, EOS patients who have undergone extensive treatment are thought to have limited capacity during exercise. The use of PFTs in this population has been a primary outcome measure of respiratory capacity; however, PFTs are dependent on effort, and thus subjective. This led us to find a new assessment of outcome, to better understand their pulmonary capacity. Patients underwent oxygen consumption (VO 2 ) testing while walking at self-selected speed over-ground and during a graded exercise test. Maximal VO 2 was predicted in those who completed the test to 85% of maximal heart rate (HR). Statistical analysis included Mann-Whitney U test and Spearman correlation coefficient (α = 0.05). 12 patients participated. Over-ground walking showed that EOS graduates chose to walk at the same speed, but at a higher VO 2 Cost (0.28 mL/kg/m) than controls (0.22 mL/kg/m; p < .001). Treadmill exercise testing showed 9 of 12 subjects able to complete the 85% of predicted maximum protocol. The EOS group had lower VO 2 during the final stage (27.9 mL/kg/min) compared to controls (34.2 mL/kg/min; p = .021); however, their heart rate reached the same values. Subjects completing the protocol had lower predicted VO 2 max (38.5 mL/kg/min) compared with controls (45.0 mL/kg/min), but this was not significant. Although PFT data suggest clinically relevant pulmonary compromise in EOS patients, the current study shows that these children are able to keep up with their peers in daily activities and also have the capacity to exercise. Level II, therapeutic. Copyright © 2016 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

Exercise training raises daily activity stronger than predicted from exercise capacity in patients with COPD.

PubMed

Behnke, Michaela; Wewel, Alexandra R; Kirsten, Detlef; Jörres, Rudolf A; Magnussen, Helgo

2005-06-01

The 6-min walking (6MWD) and 6-min treadmill distance (6MTD) are often used as measures of exercise performance in patients with COPD. The aim of our study was to assess their relationship to daily activity in the course of an exercise training program. Eighty-eight patients with stable COPD (71m/17f; mean +/- SD age, 60 +/-8 year; FEV1, 43+/-14% pred) were recruited, 66 of whom performed a hospital-based 10-day walking training, whereas 22 were treated as control. On day 16MTD, and on days 8 and 10, 6MTD and 6MWD were determined. In addition, patients used an accelerometer (TriTrac-R3D) to record 24 h-activity, whereby training sessions were excluded. In both groups there was a linear relationship (r > or = 0.84 and P < 0.0001) between 6MTD and 24 h-activity, the slope of which was 2.5-fold greater in the training group (P < 0.01). Similar relationships emerged for 6MWD. There was no association between baseline 6MTD, FEV1 or BMI and any of the other measures. These data suggest that daily activity did not markedly vary with exercise capacity under baseline conditions. Participation in a training program increased activity significantly stronger than predicted from the gain in exercise capacity. This underlines the importance of non-physiological, patient-centered factors associated with training in COPD.

High-intensity interval training improves peak oxygen uptake and muscular exercise capacity in heart transplant recipients.

PubMed

Nytrøen, K; Rustad, L A; Aukrust, P; Ueland, T; Hallén, J; Holm, I; Rolid, K; Lekva, T; Fiane, A E; Amlie, J P; Aakhus, S; Gullestad, L

2012-11-01

Heart transplant (HTx) recipients usually have reduced exercise capacity with reported VO(2peak) levels of 50-70% predicted value. Our hypothesis was that high-intensity interval training (HIIT) is an applicable and safe form of exercise in HTx recipients and that it would markedly improve VO(2peak.) Secondarily, we wanted to evaluate central and peripheral mechanisms behind a potential VO(2peak) increase. Forty-eight clinically stable HTx recipients >18 years old and 1-8 years after HTx underwent maximal exercise testing on a treadmill and were randomized to either exercise group (a 1-year HIIT-program) or control group (usual care). The mean ± SD age was 51 ± 16 years, 71% were male and time from HTx was 4.1 ± 2.2 years. The mean VO(2peak) difference between groups at follow-up was 3.6 [2.0, 5.2] mL/kg/min (p < 0.001). The exercise group had 89.0 ± 17.5% of predicted VO(2peak) versus 82.5 ± 20.0 in the control group (p < 0.001). There were no changes in cardiac function measured by echocardiography. We have demonstrated that a long-term, partly supervised and community-based HIIT-program is an applicable, effective and safe way to improve VO(2peak) , muscular exercise capacity and general health in HTx recipients. The results indicate that HIIT should be more frequently used among stable HTx recipients in the future. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

Exercise physiology, testing, and training in patients supported by a left ventricular assist device.

PubMed

Loyaga-Rendon, Renzo Y; Plaisance, Eric P; Arena, Ross; Shah, Keyur

2015-08-01

The left ventricular assist device (LVAD) is an accepted treatment alternative for the management of end-stage heart failure. As we move toward implantation of LVADs in less severe cases of HF, scrutiny of functional capacity and quality of life becomes more important. Patients demonstrate improvements in exercise capacity after LVAD implantation, but the effect is less than predicted. Exercise training produces multiple beneficial effects in heart failure patients, which would be expected to improve quality of life. In this review, we describe factors that are thought to participate in the persistent exercise impairment in LVAD-supported patients, summarize current knowledge about the effect of exercise training in LVAD-supported patients, and suggest areas for future research. Copyright © 2015 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

Value of echo-Doppler derived pulmonary vascular resistance, net-atrioventricular compliance and tricuspid annular velocity in determining exercise capacity in patients with mitral stenosis.

PubMed

Choi, Eui-Young; Shim, Jaemin; Kim, Sung-Ai; Shim, Chi Young; Yoon, Se-Jung; Kang, Seok-Min; Choi, Donghoon; Ha, Jong-Won; Rim, Se-Joong; Jang, Yangsoo; Chung, Namsik

2007-11-01

The present study sought to determine if echo-Doppler-derived pulmonary vascular resistance (PVR echo), net-atrioventricular compliance (Cn) and tricuspid peak systolic annular velocity (Sa), as parameters of right ventricular function, have value in predicting exercise capacity in patients with mitral stenosis (MS). Thirty-two patients with moderate or severe MS without left ventricular systolic dysfunction were studied. After comprehensive echo-Doppler measurements, including PVR echo, tricuspid Sa and left-sided Cn, supine bicycle exercise echo and concomitant respiratory gas analysis were performed. Measurements during 5 cardiac cycles representing the mean heart rate were averaged. Increment of resting PVR(echo) (r=-0.416, p=0.018) and decrement of resting Sa (r=0.433, p=0.013) and Cn (r=0.469, p=0.007) were significantly associated with decrease in %VO(2) peak. The predictive accuracy for %VO2 peak could increase by combining these parameters as Sa/PVR echo (r=0.500, p=0.004) or Cn. (Sa/PVR echo) (r=0.572, p=0.001) independent of mitral valve area, mean diastolic pressure gradients or presence of atrial fibrillation. Measurement of PVR echo, Cn and Sa might provide important information about the exercise capacity of patients with MS.

Smoking status and its relationship with exercise capacity, physical activity in daily life and quality of life in physically independent, elderly individuals.

PubMed

Mesquita, R; Gonçalves, C G; Hayashi, D; Costa, V de S P; Teixeira, D de C; de Freitas, E R F S; Felcar, J M; Pitta, F; Molari, M; Probst, V S

2015-03-01

To investigate the relationship between smoking status and exercise capacity, physical activity in daily life and health-related quality of life in physically independent, elderly (≥60 years) individuals. Cross-sectional, observational study. Community-dwelling, elderly individuals. One hundred and fifty-four elderly individuals were categorised into four groups according to their smoking status: never smokers (n=57), passive smokers (n=30), ex-smokers (n=45) and current smokers (n=22). Exercise capacity [6-minute walk test (6MWT)], physical activity in daily life (step counting) and health-related quality of life [36-Item Short Form Health Survey (SF-36) questionnaire] were assessed. Current and ex-smokers had lower mean exercise capacity compared with never smokers: 90 [standard deviation (SD) 10] % predicted, 91 (SD 12) % predicted and 100 (SD 13) % predicted distance on 6MWT, respectively [mean differences -9.8%, 95% confidence intervals (CI) -17.8 to -1.8 and -9.1%, 95% CI -15.4 to -2.7, respectively; P<0.05 for both]. The level of physical activity did not differ between the groups, but was found to correlate negatively with the level of nicotine dependence in current smokers (r=-0.47, P=0.03). The median score for the mental health dimension of SF-36 was worse in passive {72 [interquartile range (IQR) 56 to 96] points} and current [76 (IQR 55 to 80) points] smokers compared with ex-smokers [88 (IQR 70 to 100) points] (median differences -16 points, 95% CI -22.2 to -3.0 and -12 points, 95% CI -22.8 to -2.4, respectively; P<0.05 for both). Among elderly individuals, current smokers had lower exercise capacity than never smokers. Although the level of physical activity did not differ between the groups, an association was found with smoking. Tobacco exposure was associated with worse scores for the mental health dimension of SF-36 in physically independent, elderly individuals. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Reduced exercise capacity in genetic haemochromatosis.

PubMed

Davidsen, Einar Skulstad; Liseth, Knut; Omvik, Per; Hervig, Tor; Gerdts, Eva

2007-06-01

Many patients with genetic haemochromatosis complain about fatigue and reduced physical capacity. Exercise capacity, however, has not been evaluated in larger series of haemochromatosis patients treated with repeated phlebotomy. We performed exercise echocardiography in 152 treated haemochromatosis patients (48+/-13 years, 26% women) and 50 healthy blood donors (49+/-13 years, 30% women), who served as controls. Echocardiography was performed at rest and during exercise in a semiupright position on a chair bicycle, starting from 20 W, increasing by 20 W/min. Transmitral early and atrial velocity and isovolumic relaxation time were measured at each step. Ventilatory gas exchange was measured by the breath-to-breath-technique. Compared with healthy controls, haemochromatosis patients were more obese and less trained. More of them smoked, and 17% had a history of cardiovascular or pulmonary disease. Adjusted for training, the left ventricular function and dimensions at rest did not differ between the groups. During exercise the haemochromatosis patients obtained a significantly lower peak oxygen (O2) uptake (28.1 vs. 34.4 ml/kg per min, P<0.001). In a multiple regression analysis haemochromatosis predicted lower peak O2 uptake independently of significant contributions of sex, age, and height, as well as of systolic blood pressure and log-transformed isovolumic relaxation time at peak exercise, whereas no independent association was found with weight or physical activity (multiple R=0.74, P<0.001). Adding genotype, s-ferritin, prevalence of smoking, or history of cardiopulmonary disease among the covariates in subsequent models did not change the results. Genetic haemochromatosis, even when treated with regular phlebotomy, is associated with lower exercise capacity independently of other covariates of exercise capacity.

Pulmonary gas exchange efficiency during exercise breathing normoxic and hypoxic gas in adults born very preterm with low diffusion capacity.

PubMed

Duke, Joseph W; Elliott, Jonathan E; Laurie, Steven S; Beasley, Kara M; Mangum, Tyler S; Hawn, Jerold A; Gladstone, Igor M; Lovering, Andrew T

2014-09-01

Adults with a history of very preterm birth (<32 wk gestational age; PRET) have reduced lung function and significantly lower lung diffusion capacity for carbon monoxide (DLCO) relative to individuals born at term (CONT). Low DLCO may predispose PRET to diffusion limitation during exercise, particularly while breathing hypoxic gas because of a reduced O2 driving gradient and pulmonary capillary transit time. We hypothesized that PRET would have significantly worse pulmonary gas exchange efficiency [i.e., increased alveolar-to-arterial Po2 difference (AaDO2)] during exercise breathing room air or hypoxic gas (FiO2 = 0.12) compared with CONT. To test this hypothesis, we compared the AaDO2 in PRET (n = 13) with a clinically mild reduction in DLCO (72 ± 7% of predicted) and CONT (n = 14) with normal DLCO (105 ± 10% of predicted) pre- and during exercise breathing room air and hypoxic gas. Measurements of temperature-corrected arterial blood gases, and direct measure of O2 saturation (SaO2), were made prior to and during exercise at 25, 50, and 75% of peak oxygen consumption (V̇o2peak) while breathing room air and hypoxic gas. In addition to DLCO, pulmonary function and exercise capacity were significantly less in PRET. Despite PRET having low DLCO, no differences were observed in the AaDO2 or SaO2 pre- or during exercise breathing room air or hypoxic gas compared with CONT. Although our findings were unexpected, we conclude that reduced pulmonary function and low DLCO resulting from very preterm birth does not cause a measureable reduction in pulmonary gas exchange efficiency. Copyright © 2014 the American Physiological Society.

Quantitative chest computed tomography as a means of predicting exercise performance in severe emphysema.

PubMed

Crausman, R S; Ferguson, G; Irvin, C G; Make, B; Newell, J D

1995-06-01

We assessed the value of quantitative high-resolution computed tomography (CT) as a diagnostic and prognostic tool in smoking-related emphysema. We performed an inception cohort study of 14 patients referred with emphysema. The diagnosis of emphysema was based on a compatible history, physical examination, chest radiograph, CT scan of the lung, and pulmonary physiologic evaluation. As a group, those who underwent exercise testing were hyperinflated (percentage predicted total lung capacity +/- standard error of the mean = 133 +/- 9%), and there was evidence of air trapping (percentage predicted respiratory volume = 318 +/- 31%) and airflow limitation (forced expiratory volume in 1 sec [FEV1] = 40 +/- 7%). The exercise performance of the group was severely limited (maximum achievable workload = 43 +/- 6%) and was characterized by prominent ventilatory, gas exchange, and pulmonary vascular abnormalities. The quantitative CT index was markedly elevated in all patients (76 +/- 9; n = 14; normal < 4). There were correlations between this quantitative CT index and measures of airflow limitation (FEV1 r2 = .34, p = 09; FEV1/forced vital capacity r2 = .46, p = .04) and between maximum workload achieved (r2 = .93, p = .0001) and maximum oxygen utilization (r2 = .83, p = .0007). Quantitative chest CT assessment of disease severity is correlated with the degree of airflow limitation and exercise impairment in pulmonary emphysema.

Number of thoracotomies predicts impairment in lung function and exercise capacity in patients with congenital heart disease.

PubMed

Müller, Jan; Ewert, Peter; Hager, Alfred

2018-01-01

Many patients with congenital heart disease (CHD) require surgery to ensure survival into adulthood. But history of previous thoracotomies is associated with respiratory muscle weakness, impairments in chest wall compliance, and moderately to severely impaired lung function. This study evaluated the impact of thoracotomies on functional outcome in patients with CHD. In total 1372 adolescents and adults with CHD (32.4±11.5 years, 624 female), who underwent spirometry and cardiopulmonary exercise testing in our institution from January 2010 to August 2015, were analyzed. After adjusting for confounding variables, with every thoracotomy the prevalence for a restrictive ventilatory pattern increased by 1.8-fold (CI: 1.606-2.050; p<0.001). The number of thoracotomies had no direct influence on an impaired exercise capacity in a multivariate model, but with every percentage point increase in forced vital capacity probability of impaired exercise capacity diminished (OR: 0.944, CI: 0.933-0.955, p<0.001). There was a moderate correlation of forced vital capacity and peak oxygen uptake (r=0.464, p<0.001). After a follow-up of 2.1±1.6 years 21 patients had died. Survival was only related to age (p<0.001) and peak oxygen uptake (p<0.001) after considering together with thoracotomies, oxygen saturation at rest and forced vital capacity in a multivariate model. Independent of CHD complexity and other risk factors, multiple thoracotomies lead to restrictive lung pattern. It could be suggested that those limitations in forced vital capacity contribute to impairments in exercise capacity, which turned out to be the strongest predictor for survival. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

High Mid-Flow to Vital Capacity Ratio and the Response to Exercise in Children With Congenital Heart Disease.

PubMed

Vilozni, Daphna; Alcaneses-Ofek, Maria Rosario; Reuveny, Ronen; Rosenblum, Omer; Inbar, Omri; Katz, Uriel; Ziv-Baran, Tomer; Dubnov-Raz, Gal

2016-12-01

Pulmonary mechanics may play a role in exercise intolerance in patients with congenital heart disease (CHD). A reduced FVC volume could increase the ratio between mid-flow (FEF 25-75% ) and FVC, which is termed high dysanapsis. The relationship between high dysanapsis and the response to maximum-intensity exercise in children with CHD had not yet been studied. The aim of this work was to examine whether high dysanapsis is related to the cardiopulmonary response to maximum-intensity exercise in pediatric subjects with CHD. We retrospectively collected data from 42 children and adolescents with CHD who had either high dysanapsis (ratio >1.2; n = 21) or normal dysanapsis (control) (n = 21) as measured by spirometry. Data extracted from cardiopulmonary exercise test reports included peak values of heart rate, work load, V̇ O 2 , V̇ CO 2 , and ventilation parameters and submaximum values, including ventilatory threshold and ventilatory equivalents. There were no significant differences in demographic and clinical parameters between the groups. Participants with high dysanapsis differed from controls in lower median peak oxygen consumption (65.8% vs 83.0% of predicted, P = .02), peak oxygen pulse (78.6% vs 87.8% of predicted, P = .02), ventilatory threshold (73.8% vs 85.3% of predicted, P = .03), and maximum breathing frequency (106% vs 121% of predicted, P = .035). In the high dysanapsis group only, median peak ventilation and tidal volume were significantly lower than 80% of predicted values. In children and adolescents with corrected CHD, high dysanapsis was associated with a lower ventilatory capacity and reduced aerobic fitness, which may indicate respiratory muscle impairments. Copyright © 2016 by Daedalus Enterprises.

Cardiovascular mortality prediction in veterans with arm exercise vs pharmacologic myocardial perfusion imaging.

PubMed

Martin, Wade H; Xian, Hong; Chandiramani, Pooja; Bainter, Emily; Klein, Andrew J P

2015-08-01

No data exist comparing outcome prediction from arm exercise vs pharmacologic myocardial perfusion imaging (MPI) stress test variables in patients unable to perform treadmill exercise. In this retrospective study, 2,173 consecutive lower extremity disabled veterans aged 65.4 ± 11.0years (mean ± SD) underwent either pharmacologic MPI (1730 patients) or arm exercise stress tests (443 patients) with MPI (n = 253) or electrocardiography alone (n = 190) between 1997 and 2002. Cox multivariate regression models and reclassification analysis by integrated discrimination improvement (IDI) were used to characterize stress test and MPI predictors of cardiovascular mortality at ≥10-year follow-up after inclusion of significant demographic, clinical, and other variables. Cardiovascular death occurred in 561 pharmacologic MPI and 102 arm exercise participants. Multivariate-adjusted cardiovascular mortality was predicted by arm exercise resting metabolic equivalents (hazard ratio [HR] 0.52, 95% CI 0.39-0.69, P < .001), 1-minute heart rate recovery (HR 0.61, 95% CI 0.44-0.86, P < .001), and pharmacologic and arm exercise delta (peak-rest) heart rate (both P < .001). Only an abnormal arm exercise MPI prognosticated cardiovascular death by multivariate Cox analysis (HR 1.98, 95% CI 1.04-3.77, P < .05). Arm exercise MPI defect number, type, and size provided IDI over covariates for prediction of cardiovascular mortality (IDI = 0.074-0.097). Only pharmacologic defect size prognosticated cardiovascular mortality (IDI = 0.022). Arm exercise capacity, heart rate recovery, and pharmacologic and arm exercise heart rate responses are robust predictors of cardiovascular mortality. Arm exercise MPI results are equivalent and possibly superior to pharmacologic MPI for cardiovascular mortality prediction in patients unable to perform treadmill exercise. Published by Elsevier Inc.

Exercise training with negative pressure ventilation improves exercise capacity in patients with severe restrictive lung disease: a prospective controlled study

PubMed Central

2013-01-01

Background Exercise training is of benefit for patients with restrictive lung disease. However, it tends to be intolerable for those with severe disease. We examined whether providing ventilatory assistance by using negative pressure ventilators (NPV) during exercise training is feasible for such patients and the effects of training. Methods 36 patients with restrictive lung disease were prospectively enrolled for a 12-week multidisciplinary rehabilitation program. During this program, half of them (n:18; 60.3 ± 11.6 years; 6 men; FVC: 32.5 ± 11.7% predicted ) received regular sessions of exercise training under NPV, whilst the 18 others (59.6 ± 12.3 years; 8 men; FVC: 37.7 ± 10.2% predicted) did not. Exercise capacity, pulmonary function, dyspnea and quality of life were measured. The primary endpoint was the between-group difference in change of 6 minute-walk distance (6MWD) after 12 weeks of rehabilitation. Results All patients in the NPV-exercise group were able to tolerate and completed the program. The between-group differences were significantly better in the NPV-exercise group in changes of 6MWD (34.1 ± 12.7 m vs. -32.5 ± 17.5 m; P = 0.011) and St George Score (−14.5 ± 3.6 vs. 11.8 ± 6.0; P < 0.01). There was an improvement in dyspnea sensation (Borg’s scale, from 1.4 ± 1.5 point to 0.8 ± 1.3 point, P = 0.049) and a small increase in FVC (from 0.85 ± 0.09 L to 0.91 ± 0.08 L, P = 0.029) in the NPV-exercise group compared to the control group. Conclusion Exercise training with NPV support is feasible for patients with severe restrictive lung diseases, and improves exercise capacity and health-related quality of life. PMID:23421438

Abnormal heart rate recovery and chronotropic incompetence on exercise in chronic obstructive pulmonary disease.

PubMed

Gupta, Mansi; Bansal, Vishal; Chhabra, Sunil K

2013-08-01

Chronotropic incompetence (CI; failure to reach the targeted heart rate (HR) on exercise) and a delayed HR recovery (HRR; ≤12 beats decline within the first minute after cessation) reflect autonomic dysfunction (AD) and predict adverse cardiac prognosis. As chronic obstructive pulmonary disease (COPD) is known to be associated with AD, we hypothesized that these patients may manifest these responses on exercise. The prevalence and predictors of these responses in COPD and their association with its severity have not been evaluated. Normoxemic, stable male patients with COPD (n = 39) and 11 healthy controls underwent lung function testing and incremental leg ergometry. HR responses were monitored during exercise and recovery to compute the HRR and CI. Of all the patients, 33 (84.6%) had at least one of the two exercise responses as abnormal, with the majority (23, 58.9%) having both an abnormal HRR and CI. The frequency of abnormal responses increased with increasing Global Initiative for Chronic Obstructive Lung Disease stage and body mass index, airflow obstruction, dyspnoea and exercise capacity index. After adjusting for smoking history and post-bronchodilator forced expiratory volume in 1 second, only a reduced diffusion capacity for carbon monoxide predicted abnormal HRR, though weakly. We concluded that abnormal HRR and CI are common in patients with COPD. These responses are observed with increasing frequency as the severity of disease increases.

An integrated index combined by dynamic hyperinflation and exercise capacity in the prediction of morbidity and mortality in COPD.

PubMed

Ozgür, Eylem Sercan; Nayci, Sibel Atiş; Özge, Cengiz; Taşdelen, Bahar

2012-09-01

Dynamic hyperinflation (DH) and exercise limitation develop in patients with COPD; however, there is lack of knowledge about their long-term clinical consequences. We aimed to assess the impact of DH and exercise capacity in predicting mortality and also morbidity, as evaluated by emergency visits and hospital admissions in COPD patients during a 4-year period. We recruited 73 stable COPD patients. The relationships of different respiratory parameters (FEV(1)%, body mass index, 6 min walk test distance [6MWD], static hyperinflation as measured by the ratio of inspiratory capacity to total lung capacity (IC/TLC) at rest, DH as measured by the change between the post- and pre-exercise values of IC/TLC [ΔIC/TLC], P(aO(2)), and P(aCO(2))) with emergency visits and hospital admissions because of exacerbations and also with respiratory and all-cause mortality were assessed. The median follow-up period was 47 months (IQR 45-48 months, n = 73). During the follow-up there were 8 (11%) deaths. The ΔIC/TLC value was 3.9 ± 4.6%. The Kaplan-Meier survival curve showed that the cumulative survival rate was significantly lower in the patients with ΔIC/TLC > 4 and with 6MWD ≤ 439.56 m, using these values as thresholds. (The rates for sensitivity were 100% and 87.5%, and for specificity were 56.92% and 87.69%, respectively). The Cox proportional hazards model showed that DH (hazard ratio = 1.4, 95% CI = 1.09-1.84, P = .009) and 6MWD (hazard ratio = 0.98, 95% CI = 0.97-0.99, P = .006) were independent predictors of all-cause and respiratory mortality. 6MWD, FEV(1)%, IC/TLC, and ΔIC/TLC were found to be significantly related to emergency visits (r = -0.28, r = -0.41, r = -0.24, and r = 0.38, respectively) and hospital admissions (r = -0.41, r = -0.45, r = -0.36, and r = 0.28, respectively). DH and exercise capacity are reliable and independent predictors for mortality and morbidity in COPD patients. We propose that DH and exercise capacity be considered in the assessment of long-term clinical consequences of COPD patients. Copyright 2012 Daedalus Enterprises

Physiological and computed tomographic predictors of outcome from lung volume reduction surgery.

PubMed

Washko, George R; Martinez, Fernando J; Hoffman, Eric A; Loring, Stephen H; Estépar, Raúl San José; Diaz, Alejandro A; Sciurba, Frank C; Silverman, Edwin K; Han, MeiLan K; Decamp, Malcolm; Reilly, John J

2010-03-01

Previous investigations have identified several potential predictors of outcomes from lung volume reduction surgery (LVRS). A concern regarding these studies has been their small sample size, which may limit generalizability. We therefore sought to examine radiographic and physiologic predictors of surgical outcomes in a large, multicenter clinical investigation, the National Emphysema Treatment Trial. To identify objective radiographic and physiological indices of lung disease that have prognostic value in subjects with chronic obstructive pulmonary disease being evaluated for LVRS. A subset of the subjects undergoing LVRS in the National Emphysema Treatment Trial underwent preoperative high-resolution computed tomographic (CT) scanning of the chest and measures of static lung recoil at total lung capacity (SRtlc) and inspiratory resistance (Ri). The relationship between CT measures of emphysema, the ratio of upper to lower zone emphysema, CT measures of airway disease, SRtlc, Ri, the ratio of residual volume to total lung capacity (RV/TLC), and both 6-month postoperative changes in FEV(1) and maximal exercise capacity were assessed. Physiological measures of lung elastic recoil and inspiratory resistance were not correlated with improvement in either the FEV(1) (R = -0.03, P = 0.78 and R = -0.17, P = 0.16, respectively) or maximal exercise capacity (R = -0.02, P = 0.83 and R = 0.08, P = 0.53, respectively). The RV/TLC ratio and CT measures of emphysema and its upper to lower zone ratio were only weakly predictive of postoperative changes in both the FEV(1) (R = 0.11, P = 0.01; R = 0.2, P < 0.0001; and R = 0.23, P < 0.0001, respectively) and maximal exercise capacity (R = 0.17, P = 0.0001; R = 0.15, P = 0.002; and R = 0.15, P = 0.002, respectively). CT assessments of airway disease were not predictive of change in FEV(1) or exercise capacity in this cohort. The RV/TLC ratio and CT measures of emphysema and its distribution are weak but statistically significant predictors of outcome after LVRS.

Bronchoscopic Lung Volume Reduction with Endobronchial Valves in Low-FEV1 Patients.

PubMed

Darwiche, Kaid; Karpf-Wissel, Rüdiger; Eisenmann, Stephan; Aigner, Clemens; Welter, Stefan; Zarogoulidis, Paul; Hohenforst-Schmidt, Wolfgang; Freitag, Lutz; Oezkan, Filiz

2016-01-01

Bronchoscopic lung volume reduction (BLVR) with valves has been shown to improve lung function, exercise capacity, and quality of life in patients with emphysema, but only few patients with forced expiratory volume in 1 s (FEV1) ≤20% predicted have been included in former studies. Although the procedure can be performed safely, pneumothorax is a frequent complication, which can be critical for these very severely diseased patients. The aim of the study was to assess the safety of BLVR in patients with a very advanced stage of emphysema, as indicated by FEV1 ≤20% predicted. Patients in whom BLVR was performed between January 2013 and August 2015 were included in this analysis if their baseline predicted FEV1 was ≤20%. BLVR, performed only if collateral ventilation was absent, achieved complete occlusion of the target lobe. All patients were closely monitored and were not discharged before the fourth day after BLVR. Twenty patients with FEV1 ≤20% predicted were included in the analysis. Lung volume reduction was achieved in 65% of the cases. Pneumothorax occurred in 4 cases (20%). No patient died. Lung function and exercise tolerance improved after 1 and 3 months, respectively. BLVR with valves can be safely performed in patients with FEV1 ≤20% predicted when close postprocedural monitoring is provided. Improvement in lung function and exercise capacity can be achieved. © 2016 S. Karger AG, Basel.

1Interaction between serum BDNF and aerobic fitness predicts recognition memory in healthy young adults

PubMed Central

Whiteman, Andrew; Young, Daniel E.; He, Xuemei; Chen, Tai C.; Wagenaar, Robert C.; Stern, Chantal; Schon, Karin

2013-01-01

Convergent evidence from human and non-human animal studies suggests aerobic exercise and increased aerobic capacity may be beneficial for brain health and cognition. It is thought growth factors may mediate this putative relationship, particularly by augmenting plasticity mechanisms in the hippocampus, a brain region critical for learning and memory. Among these factors, glucocorticoids, brain derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF), hormones that have considerable and diverse physiological importance, are thought to effect normal and exercise-induced hippocampal plasticity. Despite these predictions, relatively few published human studies have tested hypotheses that relate exercise and fitness to the hippocampus, and none have considered the potential links to all of these hormonal components. Here we present cross-sectional data from a study of recognition memory; serum BDNF, cortisol, IGF-1, and VEGF levels; and aerobic capacity in healthy young adults. We measured circulating levels of these hormones together with performance on a recognition memory task, and a standard graded treadmill test of aerobic fitness. Regression analyses demonstrated BDNF and aerobic fitness predict recognition memory in an interactive manner. In addition, IGF-1 was positively associated with aerobic fitness, but not with recognition memory. Our results may suggest an exercise adaptation-related change in the BDNF dose-response curve that relates to hippocampal memory. PMID:24269495

Maximal oxygen uptake is proportional to muscle fiber oxidative capacity, from chronic heart failure patients to professional cyclists.

PubMed

van der Zwaard, Stephan; de Ruiter, C Jo; Noordhof, Dionne A; Sterrenburg, Renske; Bloemers, Frank W; de Koning, Jos J; Jaspers, Richard T; van der Laarse, Willem J

2016-09-01

V̇o2 max during whole body exercise is presumably constrained by oxygen delivery to mitochondria rather than by mitochondria's ability to consume oxygen. Humans and animals have been reported to exploit only 60-80% of their mitochondrial oxidative capacity at maximal oxygen uptake (V̇o2 max). However, ex vivo quantification of mitochondrial overcapacity is complicated by isolation or permeabilization procedures. An alternative method for estimating mitochondrial oxidative capacity is via enzyme histochemical quantification of succinate dehydrogenase (SDH) activity. We determined to what extent V̇o2 max attained during cycling exercise differs from mitochondrial oxidative capacity predicted from SDH activity of vastus lateralis muscle in chronic heart failure patients, healthy controls, and cyclists. V̇o2 max was assessed in 20 healthy subjects and 28 cyclists, and SDH activity was determined from biopsy cryosections of vastus lateralis using quantitative histochemistry. Similar data from our laboratory of 14 chronic heart failure patients and 6 controls were included. Mitochondrial oxidative capacity was predicted from SDH activity using estimated skeletal muscle mass and the relationship between ex vivo fiber V̇o2 max and SDH activity of isolated single muscle fibers and myocardial trabecula under hyperoxic conditions. Mitochondrial oxidative capacity predicted from SDH activity was related (r(2) = 0.89, P < 0.001) to V̇o2 max measured during cycling in subjects with V̇o2 max ranging from 9.8 to 79.0 ml·kg(-1)·min(-1) V̇o2 max measured during cycling was on average 90 ± 14% of mitochondrial oxidative capacity. We conclude that human V̇o2 max is related to mitochondrial oxidative capacity predicted from skeletal muscle SDH activity. Mitochondrial oxidative capacity is likely marginally limited by oxygen supply to mitochondria. Copyright © 2016 the American Physiological Society.

Iron Deficiency Is a Determinant of Functional Capacity and Health-related Quality of Life 30 Days After an Acute Coronary Syndrome.

PubMed

Meroño, Oona; Cladellas, Mercè; Ribas-Barquet, Núria; Poveda, Paula; Recasens, Lluis; Bazán, Víctor; García-García, Cosme; Ivern, Consol; Enjuanes, Cristina; Orient, Salvador; Vila, Joan; Comín-Colet, Josep

2017-05-01

Iron deficiency (ID) is a prevalent condition in patients with ischemic heart disease and heart failure. Little is known about the impact of ID on exercise capacity and quality of life (QoL) in the recovery phase after an acute coronary syndrome (ACS). Iron status and its impact on exercise capacity and QoL were prospectively evaluated in 244 patients 30 days after the ACS. QoL was assessed by the standard EuroQoL-5 dimensions, EuroQoL visual analogue scale, and Heart-QoL questionnaires. Exercise capacity was analyzed by treadmill/6-minute walk tests. The effect of ID on cardiovascular mortality and readmission rate was also investigated. A total of 46% of the patients had ID. These patients had lower exercise times (366±162 vs 462±155seconds; P<.001), metabolic consumption rates (7.9±2.9 vs 9.3±2.6 METS; P=.003), and EuroQoL-5 dimensions (0.76±0.25 vs 0.84±0.16), visual analogue scale (66±16 vs 72±17), and Heart-QoL (1.9±0.6 vs 2.2±0.6) scores (P<.05). ID independently predicted lower exercise times (OR, 2.9; 95%CI, 1.1-7.6; P=.023) and worse QoL (OR, 1.9; 95%CI, 1.1-3.3; P<.001) but had no effect on cardiovascular morbidity or mortality. ID, a prevalent condition in ACS patients, results in a poorer mid-term functional recovery, as measured by exercise capacity and QoL. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

How Is Pulmonary Function and Exercise Tolerance Affected in Patients With AIS Who Have Undergone Spinal Fusion?

PubMed

Jeans, Kelly A; Lovejoy, John F; Karol, Lori A; McClung, Anna M

2017-11-01

Prospectively enrolled AIS patients who underwent spinal fusion, with 2 year follow-up. To evaluate the cardiovascular fitness and activity level in patients with AIS pre- and post-spinal fusion and to determine if initial curve magnitude or pulmonary function is predictive of exercise capacity. Researchers have tried to link pulmonary function testing (PFT) to exercise capacity; the results are mixed. Some report no improvement in PFTs or aerobic activity after surgical correction, and PFT measures were not predictive of exercise capacity. Conflicting results have shown Vo 2max results to fall within normal range in AIS patients while PFTs show minimal impairment. AIS patients underwent PFT and oxygen consumption (VO 2 ) testing during a submaximal graded exercise test (GXT) pre- and post-spinal fusion. Vo 2max was predicted in those patients who completed the test to 85% of maximal heart rate. Pre- to postoperative changes were assessed and then compared to age-matched control subjects. Correlations between Vo 2max and curve severity, pulmonary function, and activity level were assessed. Thirty-seven patients participated. Vo 2max was predicted in 23 patients pre- and postoperation. There was a significant reduction in Vo 2max postfusion (39.5 ± 6.5 mL/kg/min vs 42.1 ± 8.1 mL/kg/min, p = .033); however, compared with controls (40.5 ± 6.5 mL/kg/min), all data were within the normal range (p > .05). AIS patients reporting high activity had significantly greater Vo 2max than those reporting low activity both pre and postoperatively, but this difference only met statistical significance preop (p < .05). Curve magnitude and PFT measures were not found to correlate with Vo 2max (p > .05). Vo 2max in patients with AIS is within normal range both pre- and postfusion. Pulmonary limitations are accommodated for with a slightly increased breathing rate and a slightly reduced overall workload. Activity level rather than curve severity affects Vo 2max outcomes following fusion in AIS. Copyright © 2017 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

Estimating exercise capacity from walking tests in elderly individuals with stable coronary artery disease.

PubMed

Mandic, Sandra; Walker, Robert; Stevens, Emily; Nye, Edwin R; Body, Dianne; Barclay, Leanne; Williams, Michael J A

2013-01-01

Compared with symptom-limited cardiopulmonary exercise test (CPET), timed walking tests are cheaper, well-tolerated and simpler alternative for assessing exercise capacity in coronary artery disease (CAD) patients. We developed multivariate models for predicting peak oxygen consumption (VO2peak) from 6-minute walk test (6MWT) distance and peak shuttle walk speed for elderly stable CAD patients. Fifty-eight CAD patients (72 SD 6 years, 66% men) completed: (1) CPET with expired gas analysis on a cycle ergometer, (2) incremental 10-meter shuttle walk test, (3) two 6MWTs, (4) anthropometric assessment and (5) 30-second chair stands. Linear regression models were developed for estimating VO2peak from 6MWT distance and peak shuttle walk speed as well as demographic, anthropometric and functional variables. Measured VO2peak was significantly related to 6MWT distance (r = 0.719, p < 0.001) and peak shuttle walk speed (r = 0.717, p < 0.001). The addition of demographic (age, gender), anthropometric (height, weight, body mass index, body composition) and functional characteristics (30-second chair stands) increased the accuracy of predicting VO2peak from both 6MWT distance and peak shuttle walk speed (from 51% to 73% of VO2peak variance explained). Addition of demographic, anthropometric and functional characteristics improves the accuracy of VO2peak estimate based on walking tests in elderly individuals with stable CAD. Implications for Rehabilitation Timed walking tests are cheaper, well-tolerated and simpler alternative for assessing exercise capacity in cardiac patients. Walking tests could be used to assess individual's functional capacity and response to therapeutic interventions when symptom-limited cardiopulmonary exercise testing is not practical or not necessary for clinical reasons. Addition of demographic, anthropometric and functional characteristics improves the accuracy of peak oxygen consumption estimate based on 6-minute walk test distance and peak shuttle walk speed in elderly patients with coronary artery disease.

Factors affecting the response to exercise in patients with severe pulmonary arterial hypertension.

PubMed

Flox-Camacho, Angela; Escribano-Subías, Pilar; Jiménez-López Guarch, Carmen; Fernández-Vaquero, Almudena; Martín-Ríos, Dolores; de la Calzada-Campo, Carlos Sáenz

2011-01-01

Ergospirometry objectively quantifies exercise capacity. Up until now, the response to exercise evaluated by ergospirometry in patients with pulmonary arterial hypertension has only been described in recently diagnosed.patients. Our aim is to describe the response to exercise in patients with severe pulmonary arterial hypertension under specific treatment and define which parameters determine their exercise capacity. A cross-sectional study was performed on 80 patients, 57 women, aged 45 (14), with severe pulmonary arterial hypertension (48 idiopathic, 14 related to toxic rapeseed oil, 13 to connective tissue disease, 5 to human immunodeficiency virus), mean pulmonary pressure at diagnosis 61(15)mmHg and after 49(33) months under treatment since diagnosis. Biomarkers were measured and echocardiography and ergospirometry were performed the same day. Our patients, under specific treatment, showed the typical behaviour of patients with pulmonary arterial hypertension with less limitation of both aerobic capacity and ventilatory efficiency. Being male (p=0.004), high ventilatory equivalent for carbon dioxide at anaerobic threshold (p<0.001) or biomarkers (p=0.006) were the strongest predictors of impaired peak oxygen uptake in multivariate analysis, whereas for an impaired percentage achieved of predicted value were right ventricle diastolic diameter (p<0.001), months of treatment (p=0.01) and high ventilatory equivalent for CO(2) (p<0.001). In pulmonary arterial hypertension, right ventricle dysfunction (expressed by its dilation or high NTproBNP) and impaired ventilatory inefficiency as well as being male or a short time under treatment can be considered as determining factors of impaired exercise capacity. Copyright © 2010 SEPAR. Published by Elsevier Espana. All rights reserved.

Development of Mitral Stenosis After Mitral Valve Repair: Importance of Mitral Valve Area.

PubMed

Chan, Kwan Leung; Chen, Shin-Yee; Mesana, Thierry; Lam, Buu Khanh

2017-12-01

The development of mitral stenosis (MS) is not uncommon after mitral valve (MV) repair for degenerative mitral regurgitation (MR), but the significance of MS in this setting has not been defined. We prospectively studied 110 such patients who underwent supine bicycle exercise testing to assess intracardiac hemodynamics at rest and at peak exercise. B-type natriuretic peptide (BNP) levels were measured at rest and after the exercise test. The patients also performed the 6-minute walk test and completed the 36-Item Short Form Survey (SF-36). Follow-up was performed by a review of the medical record and telephone interview. Of 110 patients, 22 had MS defined by a mitral valve area (MVA) ≤ 1.5 cm 2 . The resting and peak exercise mitral gradients and pulmonary artery systolic pressure were significantly higher in patients with MS compared with patients with an MVA > 1.5 cm 2 . BNP levels at rest and after exercise were also higher in the patients with MS, who also had lower exercise capacity and worse perception of well-being in 3 domains (physical function, vitality, and social function) on the SF-36. MVA had higher specificity and positive predictive value in predicting outcome events compared with a mean gradient of 3 or 5 mm Hg. In patients who had MV repair for degenerative MR, an MVA ≤ 1.5 cm 2 occurs in about one-fifth of patients and is associated with adverse intracardiac hemodynamics, lower exercise capacity, and adverse outcomes. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease.

PubMed

van Slooten, Ymkje J; van Melle, Joost P; Freling, Hendrik G; Bouma, Berto J; van Dijk, Arie Pj; Jongbloed, Monique Rm; Post, Martijn C; Sieswerda, Gertjan T; Huis In 't Veld, Anna; Ebels, Tjark; Voors, Adriaan A; Pieper, Petronella G

2016-01-01

To report the prevalence of aortic valve prosthesis-patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis later in life. However, the prevalence and clinical consequences of aortic PPM in ACHD are presently unknown. From the national Dutch Congenital Corvitia (CONCOR) registry, we identified 207 ACHD with an aortic valve prosthesis for this cross-sectional cohort study. Severe PPM was defined as an indexed effective orifice area ≤0.65 cm2/m2 and moderate PPM as an indexed orifice area ≤0.85 cm2/m2 measured using echocardiography. Exercise capacity was reported as percentage of predicted exercise capacity (PPEC). Of the 207 patients, 68% was male, 71% had a mechanical prosthesis and mean age at inclusion was 43.9 years ±11.4. The prevalence of PPM was 42%, comprising 23% severe PPM and 19% moderate PPM. Prevalence of PPM was higher in patients with mechanical prostheses (p<0.001). PPM was associated with poorer exercise capacity (mean PPEC 84% vs. 92%; p=0.048, mean difference =-8.3%, p=0.047). Mean follow-up was 2.6±1.1 years during which New York Heart Association (NYHA) class remained stable in most patients. PPM showed no significant effect on death or hospitalisation during follow-up (p=0.218). In this study we report a high prevalence (42%) of PPM in ACHD with an aortic valve prosthesis and an independent association of PPM with diminished exercise capacity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Nutritional status is related to fat-free mass, exercise capacity and inspiratory strength in severe chronic obstructive pulmonary disease patients.

PubMed

Sabino, Pollyane Galinari; Silva, Bruno Moreira; Brunetto, Antonio Fernando

2010-06-01

Being overweight or obese is associated with a higher rate of survival in patients with advanced chronic obstructive pulmonary disease (COPD). This paradoxical relationship indicates that the influence of nutritional status on functional parameters should be further investigated. To investigate the impact of nutritional status on body composition, exercise capacity and respiratory muscle strength in severe chronic obstructive pulmonary disease patients. Thirty-two patients (nine women) were divided into three groups according to their body mass indices (BMI): overweight/obese (25 < or = BMI < or = 34.9 kg/m(2), n=8), normal weight (18.5 < or = BMI < or = 24.9 kg/m(2), n=17) and underweight (BMI <18.5 kg/m(2), n=7). Spirometry, bioelectrical impedance, a six-minute walking distance test and maximal inspiratory and expiratory pressures were assessed. Airway obstruction was similar among the groups (p=0.30); however, overweight/obese patients had a higher fat-free mass (FFM) index [FFMI=FFM/body weight(2) (mean+/-SEM: 17+/-0.3 vs. 15+/-0.3 vs. 14+/-0.5 m/kg(2), p<0.01)], exercise capacity (90+/-8 vs. 79+/-6 vs. 57+/-8 m, p=0.02) and maximal inspiratory pressure (63+/-7 vs. 57+/-5 vs. 35+/-8 % predicted, p=0.03) in comparison to normal weight and underweight patients, respectively. In addition, on backward multiple regression analysis, FFMI was the unique independent predictor of exercise capacity (partial r=0.52, p<0.01). Severe chronic obstructive pulmonary disease (COPD) patients who were overweight or obese had a greater FFM, exercise capacity and inspiratory muscle strength than patients with the same degree of airflow obstruction who were of normal weight or underweight, and higher FFM was independently associated with higher exercise capacity. These characteristics of overweight or obese patients might counteract the drawbacks of excess weight and lead to an improved prognosis in COPD.

Non-invasive assessment of respiratory muscle function and its relationship to exercise tolerance in patients with chronic obstructive pulmonary disease.

PubMed

Chlumský, J; Filipova, P; Terl, M

2006-01-01

Most patients with chronic obstructive pulmonary disease (COPD) have impaired respiratory muscle function. Maximal oesophageal pressure correlates closely with exercise tolerance and seems to predict the distance walked during the 6-min walk test. This study assessed the non-invasive parameters of respiratory muscle function in 41 patients with COPD to investigate their relationship to pulmonary function tests and exercise tolerance. The COPD patients, who demonstrated the full range of airway obstruction severity, had a mean forced expiratory volume in 1 s of 42.5% predicted (range, 20 - 79% predicted). Both the maximal inspiratory muscle strength and non-invasive tension-time index were significantly correlated with the degree of lung hyperinflation, as expressed by the ratio of residual volume to total lung capacity, and the distance walked in 6 min. We conclude that respiratory muscle function was influenced mainly by lung hyperinflation and that it had an important effect on exercise tolerance in COPD patients.

Exercise capacity in diabetes mellitus is predicted by activity status and cardiac size rather than cardiac function: a case control study.

PubMed

Roberts, Timothy J; Burns, Andrew T; MacIsaac, Richard J; MacIsaac, Andrew I; Prior, David L; La Gerche, André

2018-03-23

The reasons for reduced exercise capacity in diabetes mellitus (DM) remains incompletely understood, although diastolic dysfunction and diabetic cardiomyopathy are often favored explanations. However, there is a paucity of literature detailing cardiac function and reserve during incremental exercise to evaluate its significance and contribution. We sought to determine associations between comprehensive measures of cardiac function during exercise and maximal oxygen consumption ([Formula: see text]peak), with the hypothesis that the reduction in exercise capacity and cardiac function would be associated with co-morbidities and sedentary behavior rather than diabetes itself. This case-control study involved 60 subjects [20 with type 1 DM (T1DM), 20 T2DM, and 10 healthy controls age/sex-matched to each diabetes subtype] performing cardiopulmonary exercise testing and bicycle ergometer echocardiography studies. Measures of biventricular function were assessed during incremental exercise to maximal intensity. T2DM subjects were middle-aged (52 ± 11 years) with a mean T2DM diagnosis of 12 ± 7 years and modest glycemic control (HbA 1c 57 ± 12 mmol/mol). T1DM participants were younger (35 ± 8 years), with a 19 ± 10 year history of T1DM and suboptimal glycemic control (HbA 1c 65 ± 16 mmol/mol). Participants with T2DM were heavier than their controls (body mass index 29.3 ± 3.4 kg/m 2 vs. 24.7 ± 2.9, P = 0.001), performed less exercise (10 ± 12 vs. 28 ± 30 MET hours/week, P = 0.031) and had lower exercise capacity ([Formula: see text]peak = 26 ± 6 vs. 38 ± 8 ml/min/kg, P < 0.0001). These differences were not associated with biventricular systolic or left ventricular (LV) diastolic dysfunction at rest or during exercise. There was no difference in weight, exercise participation or [Formula: see text]peak in T1DM subjects as compared to their controls. After accounting for age, sex and body surface area in a multivariate analysis, significant positive predictors of [Formula: see text]peak were cardiac size (LV end-diastolic volume, LVEDV) and estimated MET-hours, while T2DM was a negative predictor. These combined factors accounted for 80% of the variance in [Formula: see text]peak (P < 0.0001). Exercise capacity is reduced in T2DM subjects relative to matched controls, whereas exercise capacity is preserved in T1DM. There was no evidence of sub-clinical cardiac dysfunction but, rather, there was an association between impaired exercise capacity, small LV volumes and sedentary behavior.

Prediction of functional aerobic capacity without exercise testing

NASA Technical Reports Server (NTRS)

Jackson, A. S.; Blair, S. N.; Mahar, M. T.; Wier, L. T.; Ross, R. M.; Stuteville, J. E.

1990-01-01

The purpose of this study was to develop functional aerobic capacity prediction models without using exercise tests (N-Ex) and to compare the accuracy with Astrand single-stage submaximal prediction methods. The data of 2,009 subjects (9.7% female) were randomly divided into validation (N = 1,543) and cross-validation (N = 466) samples. The validation sample was used to develop two N-Ex models to estimate VO2peak. Gender, age, body composition, and self-report activity were used to develop two N-Ex prediction models. One model estimated percent fat from skinfolds (N-Ex %fat) and the other used body mass index (N-Ex BMI) to represent body composition. The multiple correlations for the developed models were R = 0.81 (SE = 5.3 ml.kg-1.min-1) and R = 0.78 (SE = 5.6 ml.kg-1.min-1). This accuracy was confirmed when applied to the cross-validation sample. The N-Ex models were more accurate than what was obtained from VO2peak estimated from the Astrand prediction models. The SEs of the Astrand models ranged from 5.5-9.7 ml.kg-1.min-1. The N-Ex models were cross-validated on 59 men on hypertensive medication and 71 men who were found to have a positive exercise ECG. The SEs of the N-Ex models ranged from 4.6-5.4 ml.kg-1.min-1 with these subjects.(ABSTRACT TRUNCATED AT 250 WORDS).

Best Protocol for the Sit-to-Stand Test in Subjects With COPD.

PubMed

Morita, Andrea A; Bisca, Gianna W; Machado, Felipe V C; Hernandes, Nidia A; Pitta, Fabio; Probst, Vanessa S

2018-05-22

Different protocols for the sit-to-stand test (STS) are available for assessing functional capacity in COPD. We sought to correlate each protocol of the STS (ie, the 5-repetition [5-rep STS], the 30-s STS, and the 1-min STS) with clinical outcomes in subjects with COPD. We also aimed to compare the 3 protocols of the STS, to verify their association and agreement, and to verify whether the 3 protocols are able to predict functional exercise capacity and physical activity in daily life (PADL). 23 subjects with COPD (11 men; FEV 1 53 ± 15% predicted) performed 3 protocols of the STS. Subjects also underwent the following assessments: incremental shuttle walking test, 6-min walk test (6MWT), 4-m gait speed test (4MGS), 1-repetition maximum of quadriceps muscle, assessment of PADL, and questionnaires on health-related quality of life and functional status. The 1-min STS showed significant correlations with the 6MWT (r = 0.40), 4MGS (r = 0.64), and PADL (0.40 ≤ r ≤ 0.52), and the 5-rep STS and 30-s STS were associated with the 4MGS (r = 0.54 and r = 0.52, respectively). The speed differed for each protocol (5-rep STS 0.53 ± 0.16 rep/s, 30-s STS 0.48 ± 0.13 rep/s, 1-min STS 0.45 ± 0.11 rep/s, P = .01). However, they presented good agreement (intraclass correlation coefficient ≥ 0.73 for all) and correlated well with each other (r ≥ 0.68 for all). More marked changes in peripheral oxygen saturation ( P = .004), heart rate ( P < .001), blood pressure ( P < .001), dyspnea ( P < .001), and leg fatigue ( P < .001) were found after the 1-min STS protocol. Furthermore, the 3 protocols were equally able to identify subjects with low exercise capacity or preserved exercise capacity. The 1-min STS generated higher hemodynamic demands and correlated better with clinical outcomes in subjects with COPD. Despite the difference in speed performance and physiological demands between the 5-rep STS and 1-min STS, there was a good level of agreement among the 3 protocols. In addition, all 3 tests were able to identify subjects with low exercise capacity or preserved exercise capacity. Copyright © 2018 by Daedalus Enterprises.

Pulmonary Vascular Response Patterns During Exercise in Left Ventricular Systolic Dysfunction Predict Exercise Capacity and Outcomes

PubMed Central

Lewis, Gregory D.; Murphy, Ryan M.; Shah, Ravi V.; Pappagianopoulos, Paul P.; Malhotra, Rajeev; Bloch, Kenneth D.; Systrom, David M.; Semigran, Marc J.

2012-01-01

Background Elevated resting pulmonary arterial pressure (PAP) in patients with left ventricular systolic dysfunction (LVSD) purports a poor prognosis. However, PAP response patterns to exercise in LVSD and their relationship to functional capacity and outcomes have not been characterized. Methods and Results Sixty consecutive patients with LVSD (age 60±12 years, LV ejection fraction 0.31±0.07, mean±SD) and 19 controls underwent maximum incremental cardiopulmonary exercise testing with simultaneous hemodynamic monitoring. During low-level exercise (30 Watts), LVSD subjects compared to controls, had greater augmentation in mean PAPs (15±1 vs. 5±1 mmHg), transpulmonary gradients (5±1 vs. 1±1 mmHg), and effective PA elastance (0.05±0.02 vs. −0.03±0.01 mmHg/ml, p<0.0001 for all). A linear increment in PAP relative to work (0.28±0.12 mmHg/watt) was observed in 65% of LVSD patients, which exceeded that observed in controls (0.07±0.02 mmHg/watt, P<0.0001). Exercise capacity and survival was worse in patients with a PAP/watt slope above the median than in patients with a lower slope. In the remaining 35% of LVSD patients, exercise induced a steep initial increment in PAP (0.41±0.16 mmHg/watt) followed by a plateau. The plateau pattern, compared to a linear pattern, was associated with reduced peak VO2 (10.6±2.6 vs. 13.1±4.0 ml/kg/min, P=0.005), lower right ventricular stroke work index augmentation with exercise (5.7±3.8 vs. 9.7±5.0 g/m2, P=0.002), and increased mortality (HR 8.1, 95% CI 2.7-23.8, P<0.001). Conclusions A steep increment in PAP during exercise and failure to augment PAP throughout exercise are associated with decreased exercise capacity and survival in patients with LVSD, and may therefore represent therapeutic targets. Clinical Trial Information URL: http://www.clinicaltrials.gov. Unique Identifier: NCT00309790) PMID:21292991

Arm mechanical efficiency and arm exercise capacity are relatively preserved in chronic obstructive pulmonary disease.

PubMed

Franssen, Frits M E; Wouters, Emiel F M; Baarends, Erica M; Akkermans, Marco A; Schols, Annemie M W J

2002-10-01

Previous studies indicate that energy expenditure related to physical activity is enhanced and that mechanical efficiency of leg exercise is reduced in patients with chronic obstructive pulmonary disease (COPD). However, it is yet unclear whether an inefficient energy expenditure is also present during other activities in COPD. This study was carried out to examine arm efficiency and peak arm exercise performance relative to leg exercise in 33 (23 male) patients with COPD ((mean +/- SEM) age: 61 +/- 2 yr; FEV : 40 +/- 2% of predicted) and 20 sex- and age-matched healthy controls. Body composition, pulmonary function, resting energy expenditure (REE), and peak leg and arm exercise performance were determined. To calculate mechanical efficiency, subjects performed submaximal leg and arm ergometry at 50% of achieved peak loads. During exercise testing, metabolic and ventilatory parameters were measured. In contrast to a reduced leg mechanical efficiency in patients compared with controls (15.6 +/- 0.6% and 22.5 +/- 0.6%, respectively; < 0.001), arm mechanical efficiency was comparable in both groups (COPD: 18.3 +/- 0.9%, controls: 21.0 +/- 1.2%; NS). Arm efficiency was not related to leg efficiency, pulmonary function, work of breathing, or REE. Also, arm exercise capacity was relatively preserved in patients with COPD (ratio arm peak work rate/leg peak work rate in patients: 89% vs 53% in controls; < 0.001). Mechanical efficiency and exercise capacity of the upper and lower limbs are not homogeneously affected in COPD, with a relative preservation of the upper limbs. This may have implications for screening of exercise tolerance and prescription of training interventions in patients with COPD. Future studies need to elucidate the mechanism behind this observation.

Physiological and Computed Tomographic Predictors of Outcome from Lung Volume Reduction Surgery

PubMed Central

Washko, George R.; Martinez, Fernando J.; Hoffman, Eric A.; Loring, Stephen H.; Estépar, Raúl San José; Diaz, Alejandro A.; Sciurba, Frank C.; Silverman, Edwin K.; Han, MeiLan K.; DeCamp, Malcolm; Reilly, John J.

2010-01-01

Rationale: Previous investigations have identified several potential predictors of outcomes from lung volume reduction surgery (LVRS). A concern regarding these studies has been their small sample size, which may limit generalizability. We therefore sought to examine radiographic and physiologic predictors of surgical outcomes in a large, multicenter clinical investigation, the National Emphysema Treatment Trial. Objectives: To identify objective radiographic and physiological indices of lung disease that have prognostic value in subjects with chronic obstructive pulmonary disease being evaluated for LVRS. Methods: A subset of the subjects undergoing LVRS in the National Emphysema Treatment Trial underwent preoperative high-resolution computed tomographic (CT) scanning of the chest and measures of static lung recoil at total lung capacity (SRtlc) and inspiratory resistance (Ri). The relationship between CT measures of emphysema, the ratio of upper to lower zone emphysema, CT measures of airway disease, SRtlc, Ri, the ratio of residual volume to total lung capacity (RV/TLC), and both 6-month postoperative changes in FEV1 and maximal exercise capacity were assessed. Measurements and Main Results: Physiological measures of lung elastic recoil and inspiratory resistance were not correlated with improvement in either the FEV1 (R = −0.03, P = 0.78 and R = –0.17, P = 0.16, respectively) or maximal exercise capacity (R = –0.02, P = 0.83 and R = 0.08, P = 0.53, respectively). The RV/TLC ratio and CT measures of emphysema and its upper to lower zone ratio were only weakly predictive of postoperative changes in both the FEV1 (R = 0.11, P = 0.01; R = 0.2, P < 0.0001; and R = 0.23, P < 0.0001, respectively) and maximal exercise capacity (R = 0.17, P = 0.0001; R = 0.15, P = 0.002; and R = 0.15, P = 0.002, respectively). CT assessments of airway disease were not predictive of change in FEV1 or exercise capacity in this cohort. Conclusions: The RV/TLC ratio and CT measures of emphysema and its distribution are weak but statistically significant predictors of outcome after LVRS. PMID:19965810

Quantifying the history dependency of muscle recovery from a fatiguing intermittent task.

PubMed

Rashedi, Ehsan; Nussbaum, Maury A

2017-01-25

Muscle fatigue and recovery are complex processes influencing muscle force generation capacity. While fatigue reduces this capacity, recovery acts to restore the unfatigued muscle state. Many factors can potentially affect muscle recovery, and among these may be a task dependency of recovery following an exercise. However, little has been reported regarding the history dependency of recovery after fatiguing contractions. We examined the dependency of muscle recovery subsequent to four different histories of fatiguing muscle contractions, imposed using two cycle times (30 and 60s) during low to moderate levels (15% and 25% of maximum voluntary contraction (MVC)) of intermittent static exertions involving index finger abduction. MVC and low-frequency electrical stimulation (LFES) measures (i.e., magnitude, rise and relaxation rates) of muscle capacity were used, all of which indicated a dependency of muscle recovery on the muscle capacity state existing immediately after fatiguing exercise. This dependency did not appear to be modified by either the cycle time or exertion level leading to that state. These results imply that the post-exercise rate of recovery is primarily influenced by the immediate post-exercise muscle contractile status (estimated by MVC and LFES measures). Such results may help improve existing models of muscle recovery, facilitating more accurate predictions of localized muscle fatigue development and thereby helping to enhance muscle performance and reduce the risk of injury. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ability of exercise testing to predict cardiovascular and all-cause death in asymptomatic women: a 20-year follow-up of the lipid research clinics prevalence study.

PubMed

Mora, Samia; Redberg, Rita F; Cui, Yadong; Whiteman, Maura K; Flaws, Jodi A; Sharrett, A Richey; Blumenthal, Roger S

2003-09-24

The value of exercise testing in women has been questioned. To determine the prognostic value of exercise testing in a population-based cohort of asymptomatic women followed up for 20 years. Near-maximal Bruce-protocol treadmill test data from the Lipid Research Clinics Prevalence Study (1972-1976) with follow-up through 1995. A total of 2994 asymptomatic North American women, aged 30 to 80 years, without known cardiovascular disease. Cardiovascular and all-cause mortality. There were 427 (14%) deaths during 20 years of follow-up, of which 147 were due to cardiovascular causes. Low exercise capacity, low heart rate recovery (HRR), and not achieving target heart rate were independently associated with increased all-cause and cardiovascular mortality. There was no increased cardiovascular death risk for exercise-induced ST-segment depression (age-adjusted hazard ratio, 1.02; 95% confidence interval [CI], 0.57-1.80; P =.96). The age-adjusted hazard ratio for cardiovascular death for every metabolic equivalent (MET) decrement in exercise capacity was 1.20 (95% CI, 1.18-1.30; P<.001); for every 10 beats per minute decrement in HRR, the hazard ratio was 1.36 (95% CI, 1.19-1.55; P<.001). After adjusting for multiple other risk factors, women who were below the median for both exercise capacity and HRR had a 3.5-fold increased risk of cardiovascular death (95% CI, 1.57-7.86; P =.002) compared with those above the median for both variables. Among women with low risk Framingham scores, those with below median levels of both exercise capacity and HRR had significantly increased risk compared with women who had above median levels of these 2 exercise variables, 44.5 and 3.5 cardiovascular deaths per 10 000 person-years, respectively (hazard ratio for cardiovascular death, 12.93; 95% CI, 5.62-29.73; P<.001). The prognostic value of exercise testing in asymptomatic women derives not from electrocardiographic ischemia but from fitness-related variables.

Alveolar-Membrane Diffusing Capacity Limits Performance in Boston Marathon Qualifiers

PubMed Central

Lavin, Kaleen M.; Straub, Allison M.; Uhranowsky, Kathleen A.; Smoliga, James M.; Zavorsky, Gerald S.

2012-01-01

Purpose (1) to examine the relation between pulmonary diffusing capacity and marathon finishing time, and (2), to evaluate the accuracy of pulmonary diffusing capacity for nitric oxide (DLNO) in predicting marathon finishing time relative to that of pulmonary diffusing capacity for carbon monoxide (DLCO). Methods 28 runners [18 males, age = 37 (SD 9) years, body mass = 70 (13) kg, height = 173 (9) cm, percent body fat = 17 (7) %] completed a test battery consisting of measurement of DLNO and DLCO at rest, and a graded exercise test to determine running economy and aerobic capacity prior to the 2011 Steamtown Marathon (Scranton, PA). One to three weeks later, all runners completed the marathon (range: 2∶22:38 to 4∶48:55). Linear regressions determined the relation between finishing time and a variety of anthropometric characteristics, resting lung function variables, and exercise parameters. Results In runners meeting Boston Marathon qualification standards, 74% of the variance in marathon finishing time was accounted for by differences in DLNO relative to body surface area (BSA) (SEE = 11.8 min, p<0.01); however, the relation between DLNO or DLCO to finishing time was non-significant in the non-qualifiers (p = 0.14 to 0.46). Whereas both DLCO and DLNO were predictive of finishing time for all finishers, DLNO showed a stronger relation (r2 = 0.30, SEE = 33.4 min, p<0.01) compared to DLCO when considering BSA. Conclusion DLNO is a performance-limiting factor in only Boston qualifiers. This suggests that alveolar-capillary membrane conductance is a limitation to performance in faster marathoners. Additionally, DLNO/BSA predicts marathon finishing time and aerobic capacity more accurately than DLCO. PMID:22984520

Reduced exercise capacity in persons with Down syndrome: cause, effect, and management

PubMed Central

Mendonca, Goncalo V; Pereira, Fernando D; Fernhall, Bo

2010-01-01

Persons with Down syndrome (DS) have reduced peak and submaximal exercise capacity. Because ambulation is one predictor of survival among adults with DS, a review of the current knowledge of the causes, effects, and management of reduced exercise capacity in these individuals would be important. Available data suggest that reduced exercise capacity in persons with DS results from an interaction between low peak oxygen uptake (VO2peak) and poor exercise economy. Of several possible explanations, chronotropic incompetence has been shown to be the primary cause of low VO2peak in DS. In contrast, poor exercise economy is apparently dependent on disturbed gait kinetics and kinematics resulting from joint laxity and muscle hypotonia. Importantly, there is enough evidence to suggest that such low levels of physical fitness (reduced exercise capacity and muscle strength) limit the ability of adults with DS to perform functional tasks of daily living. Consequently, clinical management of reduced exercise capacity in DS seems important to ensure that these individuals remain productive and healthy throughout their lives. However, few prospective studies have examined the effects of structured exercise training in this population. Existent data suggest that exercise training is beneficial for improving exercise capacity and physiological function in persons with DS. This article reviews the current knowledge of the causes, effects, and management of reduced exercise capacity in DS. This review is limited to the acute and chronic responses to submaximal and peak exercise intensities because data on supramaximal exercise capacity of persons with DS have been shown to be unreliable. PMID:21206759

Exercise capacity, muscle strength and fatigue in sarcoidosis.

PubMed

Marcellis, R G J; Lenssen, A F; Elfferich, M D P; De Vries, J; Kassim, S; Foerster, K; Drent, M

2011-09-01

The aim of this case-control study was to investigate the prevalence of exercise intolerance, muscle weakness and fatigue in sarcoidosis patients. Additionally, we evaluated whether fatigue can be explained by exercise capacity, muscle strength or other clinical characteristics (lung function tests, radiographic stages, prednisone usage and inflammatory markers). 124 sarcoidosis patients (80 males) referred to the Maastricht University Medical Centre (Maastricht, the Netherlands) were included (mean age 46.6±10.2 yrs). Patients performed a 6-min walk test (6MWT) and handgrip force (HGF), elbow flexor muscle strength (EFMS), quadriceps peak torque (QPT) and hamstring peak torque (HPT) tests. Maximal inspiratory pressure (P(I,max)) was recorded. All patients completed the Fatigue Assessment Scale (FAS) questionnaire. The 6MWT was reduced in 45% of the population, while HGF, EFMS, QPT and HPT muscle strength were reduced in 15, 12, 27 and 18%, respectively. P(I,max) was reduced in 43% of the population. The majority of the patients (81%) reported fatigue (FAS ≥22). Patients with reduced peripheral muscle strength of the upper and/or lower extremities were more fatigued and demonstrated impaired lung functions, fat-free mass, P(I,max), 6MWT and quality of life. Fatigue was neither predicted by exercise capacity, nor by muscle strength. Besides fatigue, exercise intolerance and muscle weakness are frequent problems in sarcoidosis. We therefore recommend physical tests in the multidisciplinary management of sarcoidosis patients, even in nonfatigued patients.

What's the secret behind the benefits of whole-body vibration training in patients with COPD? A randomized, controlled trial.

PubMed

Gloeckl, Rainer; Jarosch, Inga; Bengsch, Ulrike; Claus, Magdalena; Schneeberger, Tessa; Andrianopoulos, Vasileios; Christle, Jeffrey W; Hitzl, Wolfgang; Kenn, Klaus

2017-05-01

Several studies have shown that whole-body vibration training (WBVT) improves exercise capacity in patients with severe COPD. The aim of this study was to investigate the determinants of improved exercise capacity following WBVT. Seventy-four COPD patients (FEV 1 : 34 ± 9%predicted) were recruited during a 3-week inpatient pulmonary rehabilitation (PR) program. Conventional endurance and strength exercises were supplemented with self-paced dynamic squat training sessions (4bouts*2min, 3times/wk). Patients were randomly allocated to either a WBVT-group performing squat training on a side-alternating vibration platform (Galileo) at a high intensity (24-26 Hz) or a control group performing squat training without WBVT. Patients in the WBVT group significantly improved postural balance in several domains compared to the control-group (i.e. tandem stance: WBVT +20% (95%CI 14 to 26) vs. control -10% (95%CI 6 to 15), p < 0.001; one-leg stance: WBVT +11% (95%CI 4 to 19) vs. control -8% (95%CI -19 to 3), p = 0.009). Six-minute walk distance and muscle power but not muscle strength were also significantly improved compared to control group. Implementation of WBVT improves postural balance performance and muscle power output. The neuromuscular adaptation related to improved balance performance may be an important mechanism of the improvement in exercise capacity after WBVT especially in COPD patients with impaired balance performance and low exercise capacity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Administrative integration of vertical HIV monitoring and evaluation into health systems: a case study from South Africa

PubMed Central

Kawonga, Mary; Fonn, Sharon; Blaauw, Duane

2013-01-01

Background In light of an increasing global focus on health system strengthening and integration of vertical programmes within health systems, methods and tools are required to examine whether general health service managers exercise administrative authority over vertical programmes. Objective To measure the extent to which general health service (horizontal) managers, exercise authority over the HIV programme's monitoring and evaluation (M&E) function, and to explore factors that may influence this exercise of authority. Methods This cross-sectional survey involved interviews with 51 managers. We drew ideas from the concept of ‘exercised decision-space’ – traditionally used to measure local level managers’ exercise of authority over health system functions following decentralisation. Our main outcome measure was the degree of exercised authority – classified as ‘low’, ‘medium’ or ‘high’ – over four M&E domains (HIV data collection, collation, analysis, and use). We applied ordinal logistic regression to assess whether actor type (horizontal or vertical) was predictive of a higher degree of exercised authority, independent of management capacity (training and experience), and M&E knowledge. Results Relative to vertical managers, horizontal managers had lower HIV M&E knowledge, were more likely to exercise a higher degree of authority over HIV data collation (OR 7.26; CI: 1.9, 27.4), and less likely to do so over HIV data use (OR 0.19; CI: 0.05, 0.84). A higher HIV M&E knowledge score was predictive of a higher exercised authority over HIV data use (OR 1.22; CI: 0.99, 1.49). There was no association between management capacity and degree of authority. Conclusions This study demonstrates a HIV M&E model that is neither fully vertical nor integrated. The HIV M&E is characterised by horizontal managers producing HIV information while vertical managers use it. This may undermine policies to strengthen integrated health system planning and management under the leadership of horizontal managers. PMID:23364092

Administrative integration of vertical HIV monitoring and evaluation into health systems: a case study from South Africa.

PubMed

Kawonga, Mary; Fonn, Sharon; Blaauw, Duane

2013-01-24

In light of an increasing global focus on health system strengthening and integration of vertical programmes within health systems, methods and tools are required to examine whether general health service managers exercise administrative authority over vertical programmes. To measure the extent to which general health service (horizontal) managers, exercise authority over the HIV programme's monitoring and evaluation (M&E) function, and to explore factors that may influence this exercise of authority. This cross-sectional survey involved interviews with 51 managers. We drew ideas from the concept of 'exercised decision-space' - traditionally used to measure local level managers' exercise of authority over health system functions following decentralisation. Our main outcome measure was the degree of exercised authority - classified as 'low', 'medium' or 'high' - over four M&E domains (HIV data collection, collation, analysis, and use). We applied ordinal logistic regression to assess whether actor type (horizontal or vertical) was predictive of a higher degree of exercised authority, independent of management capacity (training and experience), and M&E knowledge. Relative to vertical managers, horizontal managers had lower HIV M&E knowledge, were more likely to exercise a higher degree of authority over HIV data collation (OR 7.26; CI: 1.9, 27.4), and less likely to do so over HIV data use (OR 0.19; CI: 0.05, 0.84). A higher HIV M&E knowledge score was predictive of a higher exercised authority over HIV data use (OR 1.22; CI: 0.99, 1.49). There was no association between management capacity and degree of authority. This study demonstrates a HIV M&E model that is neither fully vertical nor integrated. The HIV M&E is characterised by horizontal managers producing HIV information while vertical managers use it. This may undermine policies to strengthen integrated health system planning and management under the leadership of horizontal managers.

Exercise Capacity and Self-Efficacy are Associated with Moderate-to-Vigorous Intensity Physical Activity in Children with Congenital Heart Disease.

PubMed

Banks, Laura; Rosenthal, Shelly; Manlhiot, Cedric; Fan, Chun-Po Steve; McKillop, Adam; Longmuir, Patricia E; McCrindle, Brian W

2017-08-01

This study sought to determine whether exercise capacity, self-efficacy, and gross motor skills are associated with moderate-to-vigorous physical activity (MVPA) levels in children, and if these associations differ by congenital heart disease (CHD) type. Medical history was abstracted from chart review. We assessed MVPA levels (via accelerometry), percent-predicted peak oxygen consumption ([Formula: see text] cardiopulmonary exercise test), gross motor skill percentiles (test of gross motor development version-2), and self-efficacy [children's self-perceptions of adequacy and predilection for physical activity scale (CSAPPA scale)]. CHD patients (n = 137, range 4-12 years) included children with a repaired atrial septal defect (n = 31, mean ± standard deviation MVPA = 454 ± 246 min/week), transposition of the great arteries after the arterial switch operation (n = 34, MVPA = 423 ± 196 min/week), tetralogy of Fallot after primary repair (n = 37, MVPA = 389 ± 211 min/week), or single ventricle after the Fontan procedure (n = 35, MVPA = 405 ± 256 min/week). MVPA did not differ significantly between CHD groups (p = 0.68). Higher MVPA was associated with a higher percent-predicted [Formula: see text] (EST[95% CI] = 16.9[-0.2, 34] MVPA min/week per 10% increase in percent-predicted [Formula: see text] p = 0.05) and higher self-efficacy (EST[95% CI] = 5.2[1.0, 9.3] MVPA min/week per 1-unit increase in CSAPPA score, p = 0.02), after adjustment for age, sex, and testing seasonality, with no association with CHD type. Higher MVPA was not associated with gross motor skill percentile (p = 0.92). There were no significant interactions between CHD type and percent-predicted [Formula: see text] self-efficacy scores, and gross motor skill percentiles regarding their association with MVPA (p > 0.05 for all). Greater MVPA was associated with higher exercise capacity and self-efficacy, but not gross motor skills.

Left ventricular markers of global dyssynchrony predict limited exercise capacity in heart failure, but not in patients with preserved ejection fraction.

PubMed

Bajraktari, Gani; Batalli, Arlind; Poniku, Afrim; Ahmeti, Artan; Olloni, Rozafa; Hyseni, Violeta; Vela, Zana; Morina, Besim; Tafarshiku, Rina; Vela, Driton; Rashiti, Premtim; Haliti, Edmond; Henein, Michael Y

2012-09-11

The aim of this study was to prospectively examine echocardiographic parameters that correlate and predict functional capacity assessed by 6 min walk test (6-MWT) in patients with heart failure (HF), irrespective of ejection fraction (EF). In 147 HF patients (mean age 61 ± 11 years, 50.3% male), a 6-MWT and an echo-Doppler study were performed in the same day. Global LV dyssynchrony was indirectly assessed by total isovolumic time - t-IVT [in s/min; calculated as: 60 - (total ejection time + total filling time)], and Tei index (t-IVT/ejection time). Patients were divided into two groups based on the 6-MWT distance (Group I: ≤ 300 m and Group II: >300 m), and also in two groups according to EF (Group A: LVEF ≥ 45% and Group B: LVEF < 45%). In the cohort of patients as a whole, the 6-MWT correlated with t-IVT (r = -0.49, p < 0.001) and Tei index (r = -0.43, p < 0.001) but not with any of the other clinical or echocardiographic parameters. Group I had lower hemoglobin level (p = 0.02), lower EF (p = 0.003), larger left atrium (p = 0.02), thicker interventricular septum (p = 0.02), lower A wave (p = 0.01) and lateral wall late diastolic myocardial velocity a' (p = 0.047), longer isovolumic relaxation time (r = 0.003) and longer t-IVT (p = 0.03), compared with Group II. In the patients cohort as a whole, only t-IVT ratio [1.257 (1.071-1.476), p = 0.005], LV EF [0.947 (0.903-0.993), p = 0.02], and E/A ratio [0.553 (0.315-0.972), p = 0.04] independently predicted poor 6-MWT performance (<300 m) in multivariate analysis. None of the echocardiographic measurements predicted exercise tolerance in HFpEF. In patients with HF, the limited exercise capacity, assessed by 6-MWT, is related mostly to severity of global LV dyssynchrony, more than EF or raised filling pressures. The lack of exercise predictors in HFpEF reflects its multifactorial pathophysiology.

Predicting Heart Rate at the Ventilatory Threshold for Aerobic Exercise Prescription in Persons With Chronic Stroke.

PubMed

Boyne, Pierce; Buhr, Sarah; Rockwell, Bradley; Khoury, Jane; Carl, Daniel; Gerson, Myron; Kissela, Brett; Dunning, Kari

2015-10-01

Treadmill aerobic exercise improves gait, aerobic capacity, and cardiovascular health after stroke, but a lack of specificity in current guidelines could lead to underdosing or overdosing of aerobic intensity. The ventilatory threshold (VT) has been recommended as an optimal, specific starting point for continuous aerobic exercise. However, VT measurement is not available in clinical stroke settings. Therefore, the purpose of this study was to identify an accurate method to predict heart rate at the VT (HRVT) for use as a surrogate for VT. A cross-sectional design was employed. Using symptom-limited graded exercise test (GXT) data from 17 subjects more than 6 months poststroke, prediction methods for HRVT were derived by traditional target HR calculations (percentage of HRpeak achieved during GXT, percentage of peak HR reserve [HRRpeak], percentage of age-predicted maximal HR, and percentage of age-predicted maximal HR reserve) and by regression analysis. The validity of the prediction methods was then tested among 8 additional subjects. All prediction methods were validated by the second sample, so data were pooled to calculate refined prediction equations. HRVT was accurately predicted by 80% HRpeak (R, 0.62; standard deviation of error [SDerror], 7 bpm), 62% HRRpeak (R, 0.66; SDerror, 7 bpm), and regression models that included HRpeak (R, 0.62-0.75; SDerror, 5-6 bpm). Derived regression equations, 80% HRpeak and 62% HRRpeak, provide a specific target intensity for initial aerobic exercise prescription that should minimize underdosing and overdosing for persons with chronic stroke. The specificity of these methods may lead to more efficient and effective treatment for poststroke deconditioning.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A114).

The contribution of changes in diet, exercise, and stress management to changes in coronary risk in women and men in the multisite cardiac lifestyle intervention program.

PubMed

Daubenmier, Jennifer J; Weidner, Gerdi; Sumner, Michael D; Mendell, Nancy; Merritt-Worden, Terri; Studley, Joli; Ornish, Dean

2007-02-01

The relative contribution of health behaviors to coronary risk factors in multicomponent secondary coronary heart disease (CHD) prevention programs is largely unknown. Our purpose is to evaluate the additive and interactive effects of 3-month changes in health behaviors (dietary fat intake, exercise, and stress management) on 3-month changes in coronary risk and psychosocial factors among 869 nonsmoking CHD patients (34% female) enrolled in the health insurance-based Multisite Cardiac Lifestyle Intervention Program. Analyses of variance for repeated measures were used to analyze health behaviors, coronary risk factors, and psychosocial factors at baseline and 3 months. Multiple regression analyses evaluated changes in dietary fat intake and hours per week of exercise and stress management as predictors of changes in coronary risk and psychosocial factors. Significant overall improvement in coronary risk was observed. Reductions in dietary fat intake predicted reductions in weight, total cholesterol, low-density lipoprotein cholesterol, and interacted with increased exercise to predict reductions in perceived stress. Increases in exercise predicted improvements in total cholesterol and exercise capacity (for women). Increased stress management was related to reductions in weight, total cholesterol/high-density lipoprotein cholesterol (for men), triglycerides, hemoglobin A1c (in patients with diabetes), and hostility. Improvements in dietary fat intake, exercise, and stress management were individually, additively and interactively related to coronary risk and psychosocial factors, suggesting that multicomponent programs focusing on diet, exercise, and stress management may benefit patients with CHD.

The joint impact of smoking and exercise capacity on clinical outcomes among women with suspected myocardial ischemia: the WISE study.

PubMed

Linke, Sarah E; Rutledge, Thomas; Johnson, B Delia; Olson, Marian B; Bittner, Vera; Cornell, Carol E; Shaw, Leslee J; Eteiba, Wafia; Parashar, Susmita; Sheps, David S; Vido, Diane A; Mulukutla, Suresh; Bairey Merz, C Noel

2009-04-01

Although extensive research has been conducted on both smoking and low exercise capacity alone, few studies have examined the joint impact or interaction of these two risk factors. We examined the joint and interactive effects of smoking and self-reported exercise capacity on subsequent clinical events (heart failure, myocardial infarction [MI], stroke, and cardiovascular-related mortality) among women with suspected myocardial ischemia. At baseline (1996-1999), 789 women completed angiographic testing of coronary artery disease (CAD) severity and provided self-report information about their smoking history and exercise capacity as well as demographic and other risk factor data. Incidence of clinical events among the women was tracked for a median of 5.9 years; this analysis was conducted in 2008. In an adjusted survival analysis, women with a positive smoking history and self-reported low exercise capacity had the greatest risk of experiencing a clinical event (HR = 7.7, 95% CI 2.3, 25.5), followed by women with a positive smoking history and self-reported high exercise capacity (HR = 6.9, 95% CI 2.0, 24.6) and those with a negative smoking history and self-reported low exercise capacity (HR = 4.9, 95% CI 1.5, 15.8), relative to women with a negative smoking history and self-reported high exercise capacity. Additional analyses revealed a significant interaction between smoking history and exercise capacity, such that (1) women with a positive smoking history did not experience an additional significantly greater risk due to low exercise capacity, unlike those with a negative smoking history, and (2) all women experienced a significantly greater risk due to a positive smoking history regardless of their exercise capacity. Among women with suspected myocardial ischemia, the combined protective health effects of self-reported high exercise capacity and a negative smoking history remained significant after controlling for preexisting CAD severity and other established risk factors. These findings highlight the importance of studying behavioral risk factors in combination.

An externally validated model for predicting long-term survival after exercise treadmill testing in patients with suspected coronary artery disease and a normal electrocardiogram.

PubMed

Lauer, Michael S; Pothier, Claire E; Magid, David J; Smith, S Scott; Kattan, Michael W

2007-12-18

The exercise treadmill test is recommended for risk stratification among patients with intermediate to high pretest probability of coronary artery disease. Posttest risk stratification is based on the Duke treadmill score, which includes only functional capacity and measures of ischemia. To develop and externally validate a post-treadmill test, multivariable mortality prediction rule for adults with suspected coronary artery disease and normal electrocardiograms. Prospective cohort study conducted from September 1990 to May 2004. Exercise treadmill laboratories in a major medical center (derivation set) and a separate HMO (validation set). 33,268 patients in the derivation set and 5821 in the validation set. All patients had normal electrocardiograms and were referred for evaluation of suspected coronary artery disease. The derivation set patients were followed for a median of 6.2 years. A nomogram-illustrated model was derived on the basis of variables easily obtained in the stress laboratory, including age; sex; history of smoking, hypertension, diabetes, or typical angina; and exercise findings of functional capacity, ST-segment changes, symptoms, heart rate recovery, and frequent ventricular ectopy in recovery. The derivation data set included 1619 deaths. Although both the Duke treadmill score and our nomogram-illustrated model were significantly associated with death (P < 0.001), the nomogram was better at discrimination (concordance index for right-censored data, 0.83 vs. 0.73) and calibration. We reclassified many patients with intermediate- to high-risk Duke treadmill scores as low risk on the basis of the nomogram. The model also predicted 3-year mortality rates well in the validation set: Based on an optimal cut-point for a negative predictive value of 0.97, derivation and validation rates were, respectively, 1.7% and 2.5% below the cut-point and 25% and 29% above the cut-point. Blood test-based measures or left ventricular ejection fraction were not included. The nomogram can be applied only to patients with a normal electrocardiogram. Clinical utility remains to be tested. A simple nomogram based on easily obtained pretest and exercise test variables predicted all-cause mortality in adults with suspected coronary artery disease and normal electrocardiograms.

14 CFR 385.8 - Exercise of authority in “acting” capacity.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Exercise of authority in âactingâ capacity... Provisions § 385.8 Exercise of authority in “acting” capacity. Unless the assignment provides otherwise, staff members serving in an “acting” capacity may exercise the authority assigned to the staff members...

14 CFR 385.8 - Exercise of authority in “acting” capacity.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Exercise of authority in âactingâ capacity... Provisions § 385.8 Exercise of authority in “acting” capacity. Unless the assignment provides otherwise, staff members serving in an “acting” capacity may exercise the authority assigned to the staff members...

14 CFR 385.8 - Exercise of authority in “acting” capacity.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Exercise of authority in âactingâ capacity... Provisions § 385.8 Exercise of authority in “acting” capacity. Unless the assignment provides otherwise, staff members serving in an “acting” capacity may exercise the authority assigned to the staff members...

14 CFR 385.8 - Exercise of authority in “acting” capacity.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Exercise of authority in âactingâ capacity... Provisions § 385.8 Exercise of authority in “acting” capacity. Unless the assignment provides otherwise, staff members serving in an “acting” capacity may exercise the authority assigned to the staff members...

14 CFR 385.8 - Exercise of authority in “acting” capacity.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Exercise of authority in âactingâ capacity... Provisions § 385.8 Exercise of authority in “acting” capacity. Unless the assignment provides otherwise, staff members serving in an “acting” capacity may exercise the authority assigned to the staff members...

Autonomic dysfunction predicts poor physical improvement after cardiac rehabilitation in patients with heart failure.

PubMed

Compostella, Leonida; Nicola, Russo; Tiziana, Setzu; Caterina, Compostella; Fabio, Bellotto

2014-11-01

Cardiac autonomic dysfunction, clinically expressed by reduced heart rate variability (HRV), is present in patients with congestive heart failure (CHF) and is related to the degree of left ventricular dysfunction. In athletes, HRV is an indicator of ability to improve performance. No similar data are available for CHF. The aim of this study was to assess whether HRV could predict the capability of CHF patients to improve physical fitness after a short period of exercise-based cardiac rehabilitation (CR). This was an observational, non-randomized study, conducted on 57 patients with advanced CHF, admitted to a residential cardiac rehabilitation unit 32 ± 22 days after an episode of acute heart failure. Inclusion criteria were sinus rhythm, stable clinical conditions, no diabetes and ejection fraction ≤ 35%. HRV (time-domain) and mean and minimum heart rate (HR) were evaluated using 24-h Holter at admission. Patients' physical fitness was evaluated at admission by 6-minute walking test (6MWT) and reassessed after two weeks of intensive exercise-based CR. Exercise capacity was evaluated by a symptom-limited cardiopulmonary exercise test (CPET). Patients with very depressed HRV (SDNN 55.8 ± 10.0 ms) had no improvement in their walking capacity after short CR, walked shorter absolute distances at final 6MWT (348 ± 118 vs. 470 ± 109 m; P = 0.027) and developed a peak-VO2 at CPET significantly lower than patients with greater HRV parameters (11.4 ± 3.7 vs. an average > 16 ± 4 mL/kg/min). Minimum HR, but not mean HR, showed a negative correlation (ρ = -0.319) with CPET performance. In patients with advanced CHF, depressed HRV and higher minimum HR were predictors of poor working capacity after a short period of exercise-based CR. An individualized and intensive rehabilitative intervention should be considered for these patients.

Perfusion scintigraphy and patient selection for lung volume reduction surgery.

PubMed

Chandra, Divay; Lipson, David A; Hoffman, Eric A; Hansen-Flaschen, John; Sciurba, Frank C; Decamp, Malcolm M; Reilly, John J; Washko, George R

2010-10-01

It is unclear if lung perfusion can predict response to lung volume reduction surgery (LVRS). To study the role of perfusion scintigraphy in patient selection for LVRS. We performed an intention-to-treat analysis of 1,045 of 1,218 patients enrolled in the National Emphysema Treatment Trial who were non-high risk for LVRS and had complete perfusion scintigraphy results at baseline. The median follow-up was 6.0 years. Patients were classified as having upper or non-upper lobe-predominant emphysema on visual examination of the chest computed tomography and high or low exercise capacity on cardiopulmonary exercise testing at baseline. Low upper zone perfusion was defined as less than 20% of total lung perfusion distributed to the upper third of both lungs as measured on perfusion scintigraphy. Among 284 of 1,045 patients with upper lobe-predominant emphysema and low exercise capacity at baseline, the 202 with low upper zone perfusion had lower mortality with LVRS versus medical management (risk ratio [RR], 0.56; P = 0.008) unlike the remaining 82 with high perfusion where mortality was unchanged (RR, 0.97; P = 0.62). Similarly, among 404 of 1,045 patients with upper lobe-predominant emphysema and high exercise capacity, the 278 with low upper zone perfusion had lower mortality with LVRS (RR, 0.70; P = 0.02) unlike the remaining 126 with high perfusion (RR, 1.05; P = 1.00). Among the 357 patients with non-upper lobe-predominant emphysema (75 with low and 282 with high exercise capacity) there was no improvement in survival with LVRS and measurement of upper zone perfusion did not contribute new prognostic information. Compared with optimal medical management, LVRS reduces mortality in patients with upper lobe-predominant emphysema when there is low rather than high perfusion to the upper lung.

Acute aerobic exercise hastens emotional recovery from a subsequent stressor.

PubMed

Bernstein, Emily E; McNally, Richard J

2017-06-01

Despite findings that regular exercise is broadly associated with emotional well-being, more basic research is needed to deepen our understanding of the exercise and emotion connection. This paper examines how acute aerobic exercise in particular influences subjective emotional recovery from a subsequent stressor. Potential mediators and moderators, including level of physical fitness, attentional control, and perseverative negative thinking were explored. All of the participants (n = 95) completed 3 laboratory visits, each including 1 of 3 activities (i.e., cycling, resting, stretching), tests of working memory and attentional control, and an experimental stressor. Self-reported rumination after the stressor and the experience of positive and negative emotions throughout the study were recorded. In this within-subjects paradigm, as expected, higher rumination in response to the stressor predicted more persistent negative emotion afterward; this effect was attenuated only by prior acute aerobic exercise, in this case, cycling, both 5 min and 15 min poststressor. This effect was unrelated to physical fitness or cognitive performance. Physical fitness level did predict greater attentional control and the capacity to update working memory. Acute aerobic exercise may facilitate subjective emotional recovery from a subsequent stressor and improve emotional flexibility. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The short and long term effects of exercise training in non-cystic fibrosis bronchiectasis--a randomised controlled trial.

PubMed

Lee, Annemarie L; Hill, Catherine J; Cecins, Nola; Jenkins, Sue; McDonald, Christine F; Burge, Angela T; Rautela, Linda; Stirling, Robert G; Thompson, Philip J; Holland, Anne E

2014-04-15

Exercise training is recommended for non-cystic fibrosis (CF) bronchiectasis, but the long-term effects are unclear. This randomised controlled trial aimed to determine the effects of exercise training and review of airway clearance therapy (ACT) on exercise capacity, health related quality of life (HRQOL) and the incidence of acute exacerbations in people with non-CF bronchiectasis. Participants were randomly allocated to 8 weeks of supervised exercise training and review of ACT, or control. Primary outcomes of exercise capacity and HRQOL (Chronic respiratory disease questionnaire) and secondary outcomes of cough-related QOL (Leicester cough questionnaire) and psychological symptoms (Hospital anxiety and depression scale) were measured at baseline, following completion of the intervention period and at 6 and 12 months follow up. Secondary outcomes of the exacerbation rate and time to first exacerbation were analysed over 12 months. Eighty-five participants (mean FEV1 74% predicted; median Modified Medical Research Council Dyspnoea grade of 1 (IQR [1-3]) were included. Exercise training increased the incremental shuttle walk distance (mean difference to control 62 m, 95% CI 24 to 101 m) and the 6-minute walking distance (mean difference to control 41 m, 95% CI 19 to 63 m), but these improvements were not sustained at 6 or 12 months. Exercise training reduced dyspnoea (p = 0.009) and fatigue (p = 0.01) but did not impact on cough-related QOL or mood. Exercise training reduced the frequency of acute exacerbations (median 1[IQR 1-3]) compared to the control group (2[1-3]) over 12 months follow up (p = 0.012), with a longer time to first exacerbation with exercise training of 8 months (95% CI 7 to 9 months) compared to the control group (6 months [95% CI 5 to 7 months], p = 0.047). Exercise training in bronchiectasis is associated with short term improvement in exercise capacity, dyspnoea and fatigue and fewer exacerbations over 12 months. ClinicalTrials.gov (NCT00885521).

The short and long term effects of exercise training in non-cystic fibrosis bronchiectasis – a randomised controlled trial

PubMed Central

2014-01-01

Background Exercise training is recommended for non-cystic fibrosis (CF) bronchiectasis, but the long-term effects are unclear. This randomised controlled trial aimed to determine the effects of exercise training and review of airway clearance therapy (ACT) on exercise capacity, health related quality of life (HRQOL) and the incidence of acute exacerbations in people with non-CF bronchiectasis. Methods Participants were randomly allocated to 8 weeks of supervised exercise training and review of ACT, or control. Primary outcomes of exercise capacity and HRQOL (Chronic respiratory disease questionnaire) and secondary outcomes of cough-related QOL (Leicester cough questionnaire) and psychological symptoms (Hospital anxiety and depression scale) were measured at baseline, following completion of the intervention period and at 6 and 12 months follow up. Secondary outcomes of the exacerbation rate and time to first exacerbation were analysed over 12 months. Results Eighty-five participants (mean FEV1 74% predicted; median Modified Medical Research Council Dyspnoea grade of 1 (IQR [1–3]) were included. Exercise training increased the incremental shuttle walk distance (mean difference to control 62 m, 95% CI 24 to 101 m) and the 6-minute walking distance (mean difference to control 41 m, 95% CI 19 to 63 m), but these improvements were not sustained at 6 or 12 months. Exercise training reduced dyspnoea (p = 0.009) and fatigue (p = 0.01) but did not impact on cough-related QOL or mood. Exercise training reduced the frequency of acute exacerbations (median 1[IQR 1–3]) compared to the control group (2[1–3]) over 12 months follow up (p = 0.012), with a longer time to first exacerbation with exercise training of 8 months (95% CI 7 to 9 months) compared to the control group (6 months [95% CI 5 to 7 months], p = 0.047). Conclusions Exercise training in bronchiectasis is associated with short term improvement in exercise capacity, dyspnoea and fatigue and fewer exacerbations over 12 months. Trial registry ClinicalTrials.gov (NCT00885521). PMID:24731015

A prognostic scoring system for arm exercise stress testing.

PubMed

Xie, Yan; Xian, Hong; Chandiramani, Pooja; Bainter, Emily; Wan, Leping; Martin, Wade H

2016-01-01

Arm exercise stress testing may be an equivalent or better predictor of mortality outcome than pharmacological stress imaging for the ≥50% for patients unable to perform leg exercise. Thus, our objective was to develop an arm exercise ECG stress test scoring system, analogous to the Duke Treadmill Score, for predicting outcome in these individuals. In this retrospective observational cohort study, arm exercise ECG stress tests were performed in 443 consecutive veterans aged 64.1 (11.1) years. (mean (SD)) between 1997 and 2002. From multivariate Cox models, arm exercise scores were developed for prediction of 5-year and 12-year all-cause and cardiovascular mortality and 5-year cardiovascular mortality or myocardial infarction (MI). Arm exercise capacity in resting metabolic equivalents (METs), 1 min heart rate recovery (HRR) and ST segment depression ≥1 mm were the stress test variables independently associated with all-cause and cardiovascular mortality by step-wise Cox analysis (all p<0.01). A score based on the relation HRR (bpm)+7.3×METs-10.5×ST depression (0=no; 1=yes) prognosticated 5-year cardiovascular mortality with a C-statistic of 0.81 before and 0.88 after adjustment for significant demographic and clinical covariates. Arm exercise scores for the other outcome end points yielded C-statistic values of 0.77-0.79 before and 0.82-0.86 after adjustment for significant covariates versus 0.64-0.72 for best fit pharmacological myocardial perfusion imaging models in a cohort of 1730 veterans who were evaluated over the same time period. Arm exercise scores, analogous to the Duke Treadmill Score, have good power for prediction of mortality or MI in patients who cannot perform leg exercise.

Can endurance training improve physical capacity and quality of life in young Fontan patients?

PubMed

Hedlund, Eva R; Lundell, Bo; Söderström, Liselott; Sjöberg, Gunnar

2018-03-01

Children after Fontan palliation have reduced exercise capacity and quality of life. Our aim was to study whether endurance training could improve physical capacity and quality of life in Fontan patients. Fontan patients (n=30) and healthy age- and gender-matched control subjects (n=25) performed a 6-minute walk test at submaximal capacity and a maximal cycle ergometer test. Quality of life was assessed with Pediatric Quality of Life Inventory Version 4.0 questionnaires for children and parents. All tests were repeated after a 12-week endurance training programme and after 1 year. Patients had decreased submaximal and maximal exercise capacity (maximal oxygen uptake 35.0±5.1 ml/minute per·kg versus 43.7±8.4 ml/minute·per·kg, p<0.001) and reported a lower quality of life score (70.9±9.9 versus 85.7±8.0, p<0.001) than controls. After training, patients improved their submaximal exercise capacity in a 6-minute walk test (from 590.7±65.5 m to 611.8±70.9 m, p<0.05) and reported a higher quality of life (p<0.01), but did not improve maximal exercise capacity. At follow-up, submaximal exercise capacity had increased further and improved quality of life was sustained. The controls improved their maximal exercise capacity (p<0.05), but not submaximal exercise capacity or quality of life after training. At follow-up, improvement of maximal exercise capacity was sustained. We believe that an individualised endurance training programme for Fontan patients improves submaximal exercise capacity and quality of life in Fontan patients and the effect on quality of life appears to be long-lasting.

Ventilatory Responses at Peak Exercise in Endurance-Trained Obese Adults

PubMed Central

Lorenzo, Santiago

2013-01-01

Background: Alterations in respiratory mechanics predispose healthy obese individuals to low lung volume breathing, which places them at risk of developing expiratory flow limitation (EFL). The high ventilatory demand in endurance-trained obese adults further increases their risk of developing EFL and increases their work of breathing. The objective of this study was to investigate the prevalence and magnitude of EFL in fit obese (FO) adults via measurements of breathing mechanics and ventilatory dynamics during exercise. Methods: Ten (seven women and three men) FO (mean ± SD, 38 ± 5 years, 38% ± 5% body fat) and 10 (seven women and three men) control obese (CO) (38 ± 5 years, 39% ± 5% body fat) subjects underwent hydrostatic weighing, pulmonary function testing, cycle exercise testing, and the determination of the oxygen cost of breathing during eucapnic voluntary hyperpnea. Results: There were no differences in functional residual capacity (43% ± 6% vs 40% ± 9% total lung capacity [TLC]), residual volume (21% ± 4% vs 21% ± 4% TLC), or FVC (111% ± 13% vs 104% ± 15% predicted) between FO and CO subjects, respectively. FO subjects had higher FEV1 (111% ± 13% vs 99% ± 11% predicted), TLC (106% ± 14% vs 94% ± 7% predicted), peak expiratory flow (123% ± 14% vs 106% ± 13% predicted), and maximal voluntary ventilation (128% ± 15% vs 106% ± 13% predicted) than did CO subjects. Peak oxygen uptake (129% ± 16% vs 86% ± 15% predicted), minute ventilation (128 ± 35 L/min vs 92 ± 25 L/min), and work rate (229 ± 54 W vs 166 ± 55 W) were higher in FO subjects. Mean inspiratory (4.65 ± 1.09 L/s vs 3.06 ± 1.21 L/s) and expiratory (4.15 ± 0.95 L/s vs 2.98 ± 0.76L/s) flows were greater in FO subjects, which yielded a greater breathing frequency (51 ± 8 breaths/min vs 41 ± 10 breaths/min) at peak exercise in FO subjects. Mechanical ventilatory constraints in FO subjects were similar to those in CO subjects despite the greater ventilatory demand in FO subjects. Conclusion: FO individuals achieve high ventilations by increasing breathing frequency, matching the elevated metabolic demand associated with high fitness. They do this without developing meaningful ventilatory constraints. Therefore, endurance-trained obese individuals with higher lung function are not limited by breathing mechanics during peak exercise, which may allow healthy obese adults to participate in vigorous exercise training. PMID:23722607

Ventilatory responses at peak exercise in endurance-trained obese adults.

PubMed

Lorenzo, Santiago; Babb, Tony G

2013-10-01

Alterations in respiratory mechanics predispose healthy obese individuals to low lung volume breathing, which places them at risk of developing expiratory flow limitation (EFL). The high ventilatory demand in endurance-trained obese adults further increases their risk of developing EFL and increases their work of breathing. The objective of this study was to investigate the prevalence and magnitude of EFL in fit obese (FO) adults via measurements of breathing mechanics and ventilatory dynamics during exercise. Ten (seven women and three men) FO (mean ± SD, 38 ± 5 years, 38% ± 5% body fat) and 10 (seven women and three men) control obese (CO) (38 ± 5 years, 39% ± 5% body fat) subjects underwent hydrostatic weighing, pulmonary function testing, cycle exercise testing, and the determination of the oxygen cost of breathing during eucapnic voluntary hyperpnea. There were no differences in functional residual capacity (43% ± 6% vs 40% ± 9% total lung capacity [TLC]), residual volume (21% ± 4% vs 21% ± 4% TLC), or FVC (111% ± 13% vs 104% ± 15% predicted) between FO and CO subjects, respectively. FO subjects had higher FEV1 (111% ± 13% vs 99% ± 11% predicted), TLC (106% ± 14% vs 94% ± 7% predicted), peak expiratory flow (123% ± 14% vs 106% ± 13% predicted), and maximal voluntary ventilation (128% ± 15% vs 106% ± 13% predicted) than did CO subjects. Peak oxygen uptake (129% ± 16% vs 86% ± 15% predicted), minute ventilation (128 ± 35 L/min vs 92 ± 25 L/min), and work rate (229 ± 54 W vs 166 ± 55 W) were higher in FO subjects. Mean inspiratory (4.65 ± 1.09 L/s vs 3.06 ± 1.21 L/s) and expiratory (4.15 ± 0.95 L/s vs 2.98 ± 0.76 L/s) flows were greater in FO subjects, which yielded a greater breathing frequency (51 ± 8 breaths/min vs 41 ± 10 breaths/min) at peak exercise in FO subjects. Mechanical ventilatory constraints in FO subjects were similar to those in CO subjects despite the greater ventilatory demand in FO subjects. FO individuals achieve high ventilations by increasing breathing frequency, matching the elevated metabolic demand associated with high fitness. They do this without developing meaningful ventilatory constraints. Therefore, endurance-trained obese individuals with higher lung function are not limited by breathing mechanics during peak exercise, which may allow healthy obese adults to participate in vigorous exercise training.

Effect of Beta-Blocker Therapy, Maximal Heart Rate, and Exercise Capacity During Stress Testing on Long-Term Survival (from The Henry Ford Exercise Testing Project).

PubMed

Hung, Rupert K; Al-Mallah, Mouaz H; Whelton, Seamus P; Michos, Erin D; Blumenthal, Roger S; Ehrman, Jonathan K; Brawner, Clinton A; Keteyian, Steven J; Blaha, Michael J

2016-12-01

Whether lower heart rate thresholds (defined as the percentage of age-predicted maximal heart rate achieved, or ppMHR) should be used to determine chronotropic incompetence in patients on beta-blocker therapy (BBT) remains unclear. In this retrospective cohort study, we analyzed 64,549 adults without congestive heart failure or atrial fibrillation (54 ± 13 years old, 46% women, 29% black) who underwent clinician-referred exercise stress testing at a single health care system in Detroit, Michigan from 1991 to 2009, with median follow-up of 10.6 years for all-cause mortality (interquartile range 7.7 to 14.7 years). Using Cox regression models, we assessed the effect of BBT, ppMHR, and estimated exercise capacity on mortality, with adjustment for demographic data, medical history, pertinent medications, and propensity to be on BBT. There were 9,259 deaths during follow-up. BBT was associated with an 8% lower adjusted achieved ppMHR (91% in no BBT vs 83% in BBT). ppMHR was inversely associated with all-cause mortality but with significant attenuation by BBT (per 10% ppMHR HR: no BBT: 0.80 [0.78 to 0.82] vs BBT: 0.89 [0.87 to 0.92]). Patients on BBT who achieved 65% ppMHR had a similar adjusted mortality rate as those not on BBT who achieved 85% ppMHR (p >0.05). Estimated exercise capacity further attenuated the prognostic value of ppMHR (per-10%-ppMHR HR: no BBT: 0.88 [0.86 to 0.90] vs BBT: 0.95 [0.93 to 0.98]). In conclusion, the prognostic value of ppMHR was significantly attenuated by BBT. For patients on BBT, a lower threshold of 65% ppMHR may be considered for determining worsened prognosis. Estimated exercise capacity further diminished the prognostic value of ppMHR particularly in patients on BBT. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of abdominal muscle activity and peak expiratory flow between forced vital capacity and fast expiration exercise.

PubMed

Ishida, Hiroshi; Suehiro, Tadanobu; Watanabe, Susumu

2017-04-01

[Purpose] The purpose of this investigation was to compare the activities of the abdominal muscles and peak expiratory flow between forced vital capacity and fast expiration exercise. [Subjects and Methods] Fifteen healthy male participated in this study. Peak expiratory flow and electromyographic activities of the rectus abdominis, external oblique, and internal oblique/transversus abdominis muscles were measured during forced vital capacity and fast expiration exercise and then peak amplitude and its appearance time were obtained. [Results] Peak expiratory flow values were significantly higher during fast expiration exercise than during forced vital capacity. The internal oblique/transversus abdominis muscles showed significantly higher peak amplitude during fast expiration exercise than during forced vital capacity. However, there were no significant differences between forced vital capacity and fast expiration exercise in the rectus abdominis and external oblique muscles. There was no difference in the appearance time of the peak amplitude between forced vital capacity and fast expiration exercise in any muscle. [Conclusion] Fast expiration exercise might be beneficial for increasing expiratory speed and neuromuscular activation of the internal oblique/transversus abdominis muscles compared to forced vital capacity. These findings could be considered when recommending a variation of expiratory muscle strength training as part of pulmonary rehabilitation programs.

Exercise and end-stage kidney disease: functional exercise capacity and cardiovascular outcomes.

PubMed

Parsons, Trisha L; King-Vanvlack, Cheryl E

2009-11-01

This review examined published reports of the impact of extradialytic and intradialytic exercise programs on physiologic aerobic exercise capacity, functional exercise endurance, and cardiovascular outcomes in individuals with ESKD. Studies spanning 30 years from the first published report of exercise in the ESKD population were reviewed. Studies conducted in the first half of the publication record focused on the efficacy of exercise training programs performed "off"-dialysis with respect to the modification of traditional cardiovascular risk factors, aerobic capacity, and its underlying determinants. In the latter half of the record, there had been a shift to include other client-centered goals such as physical function and quality of life. There is evidence that both intra- and extradialytic programs can significantly enhance aerobic exercise capacity, but moderate-intensity extradialytic programs may result in greater gains in those individuals who initially have extremely poor aerobic capacity. Functionally, substantive improvements in exercise endurance in excess of the minimum clinical significant difference can occur following either low- or moderate-intensity exercise regardless of the initial level of performance. Reductions in blood pressure and enhanced vascular functioning reported after predominantly intradialytic exercise programs suggest that either low- or moderate-intensity exercise programs can confer cardiovascular benefit. Regardless of prescription model, there was an overall lack of evidence regarding the impact of exercise-induced changes in exercise capacity, endurance, and cardiovascular function on a number of relevant health outcomes (survival, morbidity, and cardiovascular risk), and, more importantly, there is no evidence on the long-term impact of exercise and/or physical activity interventions on these health outcomes.

Pressure-Flow During Exercise Catheterization Predicts Survival in Pulmonary Hypertension.

PubMed

Hasler, Elisabeth D; Müller-Mottet, Séverine; Furian, Michael; Saxer, Stéphanie; Huber, Lars C; Maggiorini, Marco; Speich, Rudolf; Bloch, Konrad E; Ulrich, Silvia

2016-07-01

Pulmonary hypertension manifests with impaired exercise capacity. Our aim was to investigate whether the mean pulmonary arterial pressure to cardiac output relationship (mPAP/CO) predicts transplant-free survival in patients with pulmonary arterial hypertension (PAH) and inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Hemodynamic data according to right heart catheterization in patients with PAH and CTEPH at rest and during supine incremental cycle exercise were analyzed. Transplant-free survival and predictive value of hemodynamics were assessed by using Kaplan-Meier and Cox regression analyses. Seventy patients (43 female; 54 with PAH, 16 with CTEPH; median (quartiles) age, 65 [50; 73] years; mPAP, 34 [29; 44] mm Hg; cardiac index, 2.8 [2.3; 3.5] [L/min]/m(2)) were followed up for 610 (251; 1256) days. Survival at 1, 3, 5, and 7 years was 89%, 81%, 71%, and 59%. Age, World Health Organization-functional class, 6-min walk test, and mixed-venous oxygen saturation (but not resting hemodynamics) predicted transplant-free survival. Maximal workload (hazard ratio [HR], 0.94 [95% CI, 0.89-0.99]; P = .027), peak cardiac index (HR, 0.51 [95% CI, 0.27-0.95]; P = .034), change in cardiac index, 0.25 [95% CI, 0.06-0.94]; P = .040), and mPAP/CO (HR, 1.02 [95% CI, 1.01-1.03]; P = .003) during exercise predicted survival. Values for mPAP/CO predicted 3-year transplant-free survival with an area under the curve of 0.802 (95% CI, 0.66-0.95; P = .004). In this collective of patients with PAH or CTEPH, the pressure-flow relationship during exercise predicted transplant-free survival and correlated with established markers of disease severity and outcome. Right heart catheterization during exercise may provide important complementary prognostic information in the management of pulmonary hypertension. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Effects of exercise on functional aerobic capacity in adults with fibromyalgia syndrome: A systematic review of randomized controlled trials.

PubMed

García-Hermoso, Antonio; Saavedra, Jose M; Escalante, Yolanda

2015-01-01

Patients with fibromyalgia present a reduced capacity of upper and lower limb physical performance and affect their independence in performing everyday activities. The purpose of the present systematic review was to summarize evidence for the effectiveness and structure of exercise programs on functional aerobic capacity in patients with fibromyalgia syndrome. Keyword searches were made of seven databases. The systematic review was limited to English language studies of people with FM that evaluated the effects of exercise programs on functional aerobic capacity (6-minute walk test). The criteria for inclusion were satisfied by 12 randomized controlled trial (RCT) studies. The main cumulative evidence indicates that the programs based on aerobic exercise alone and on aquatic exercises have large (effect size = 0.85) and moderate (effect size = 0.44) effects. Aerobic and aquatic exercises at the proper intensity favour the increased functional aerobic capacity of fibromyalgia patients; however, most works do not adequately detail the intensity of the exercises. Moderate intensity exercise (aerobic and aquatic exercise) performed at least two times per week and 30-60 minutes a day is effective for increasing functional aerobic capacity, favouring the daily activities of daily living in this population.

Elevated Nicotinamide Phosphoribosyl Transferase in Skeletal Muscle Augments Exercise Performance and Mitochondrial Respiratory Capacity Following Exercise Training

PubMed Central

Brouwers, Bram; Stephens, Natalie A.; Costford, Sheila R.; Hopf, Meghan E.; Ayala, Julio E.; Yi, Fanchao; Xie, Hui; Li, Jian-Liang; Gardell, Stephen J.; Sparks, Lauren M.; Smith, Steven R.

2018-01-01

Mice overexpressing NAMPT in skeletal muscle (NamptTg mice) develop higher exercise endurance and maximal aerobic capacity (VO2max) following voluntary exercise training compared to wild-type (WT) mice. Here, we aimed to investigate the mechanisms underlying by determining skeletal muscle mitochondrial respiratory capacity in NamptTg and WT mice. Body weight and body composition, tissue weight (gastrocnemius, quadriceps, soleus, heart, liver, and epididymal white adipose tissue), skeletal muscle and liver glycogen content, VO2max, skeletal muscle mitochondrial respiratory capacity (measured by high-resolution respirometry), skeletal muscle gene expression (measured by microarray and qPCR), and skeletal muscle protein content (measured by Western blot) were determined following 6 weeks of voluntary exercise training (access to running wheel) in 13-week-old male NamptTg (exercised NamptTg) mice and WT (exercised WT) mice. Daily running distance and running time during the voluntary exercise training protocol were recorded. Daily running distance (p = 0.51) and running time (p = 0.85) were not significantly different between exercised NamptTg mice and exercised WT mice. VO2max was higher in exercised NamptTg mice compared to exercised WT mice (p = 0.02). Body weight (p = 0.92), fat mass (p = 0.49), lean mass (p = 0.91), tissue weight (all p > 0.05), and skeletal muscle (p = 0.72) and liver (p = 0.94) glycogen content were not significantly different between exercised NamptTg mice and exercised WT mice. Complex I oxidative phosphorylation (OXPHOS) respiratory capacity supported by fatty acid substrates (p < 0.01), maximal (complex I+II) OXPHOS respiratory capacity supported by glycolytic (p = 0.02) and fatty acid (p < 0.01) substrates, and maximal uncoupled respiratory capacity supported by fatty acid substrates (p < 0.01) was higher in exercised NamptTg mice compared to exercised WT mice. Transcriptomic analyses revealed differential expression for genes involved in oxidative metabolism in exercised NamptTg mice compared to exercised WT mice, specifically, enrichment for the gene set related to the SIRT3-mediated signaling pathway. SIRT3 protein content correlated with NAMPT protein content (r = 0.61, p = 0.04). In conclusion, NamptTg mice develop higher exercise capacity following voluntary exercise training compared to WT mice, which is paralleled by higher mitochondrial respiratory capacity in skeletal muscle. The changes in SIRT3 targets suggest that these effects are due to remodeling of mitochondrial function. PMID:29942262

Long-term effects of cardiac rehabilitation in elderly individuals with stable coronary artery disease.

PubMed

Mandic, Sandra; Stevens, Emily; Hodge, Claire; Brown, Casey; Walker, Robert; Body, Dianne; Barclay, Leanne; Nye, Edwin R; Williams, Michael J A

2016-01-01

To compare exercise capacity and cardiovascular response to exercise in elderly individuals with coronary artery disease (CAD) who attend ongoing community-based maintenance cardiac rehabilitation (CR) versus age- and gender-matched healthy "very active" (HVA; ≥ 2000 kcal/week) and healthy "less active" (HLA; <2000 kcal/week) individuals. Sixty-three participants (age: 72.3 ± 5.1 years; 62% men; n = 21 per group) completed the following assessments: (1) symptom-limited graded exercise test with expired gas analysis and bioimpedance assessment of cardiovascular function during exercise; (2) walking tests; (3) physical function; (4) anthropometry and (5) 12-month physical activity recall. The CR group achieved 98% (range: 73-154%) of age- and gender-predicted peak oxygen consumption for healthy individuals. Peak oxygen consumption was lower in CR compared to HVA but not HLA group (VO2peak: CR: 19.0 ± 4.5, HVA: 23.7 ± 2.9, HLA: 20.7 ± 4.7 ml ·kg(-1)ċmin(-1), p = 0.001 versus HVA; p = 0.390 versus HLA). Peak heart rate was lower in CR compared to both HVA and HLA. Walking test results and cardiovascular and physical function were not different between the groups. Elderly individuals with CAD participating in maintenance CR have similar exercise capacity and cardiorespiratory response to exercise compared to their age- and gender-matched less active healthy peers. The findings support referral of elderly patients to community-based CR. Fitness benefits of long-term maintenance cardiac rehabilitation (CR) programs remain unknown. Elderly individuals with coronary artery disease participating in maintenance CR have exercise capacity and cardiorespiratory response to exercise similar to their less active healthy peers. Maintenance CR may play an important role prolonging independent living in elderly individuals.

[Application of the 6-Minute Walking Test and Shuttle Walking Test in the Exercise Tests of Patients With COPD].

PubMed

Ho, Chiung-Fang; Maa, Suh-Hwa

2016-08-01

Exercise training improves the management of stable chronic obstructive pulmonary disease (COPD). COPD patients benefit from exercise training programs in terms of improved VO2 peak values and decreased dyspnea, fatigue, hospital admissions, and rates of mortality, increasing exercise capacity and health-related quality of life (HRQOL). COPD is often associated with impairment in exercise tolerance. About 51% of patients have a limited capacity for normal activity, which often further degrades exercise capacity, creating a vicious circle. Exercise testing is highly recommended to assess a patient's individualized functions and limitations in order to determine the optimal level of training intensity prior to initiating an exercise-training regimen. The outcomes of exercise testing provide a powerful indicator of prognosis in COPD patients. The six-minute walking test (6MWT) and the incremental shuttle-walking test (ISWT) are widely used in exercise testing to measure a patient's exercise ability by walking distances. While nursing-related articles published in Taiwan frequently cite and use the 6MWT to assess exercise capacity in COPD patients, the ISWT is rarely used. This paper introduces the testing method, strengths and weaknesses, and application of the two tests in order to provide clinical guidelines for assessing the current exercise capacity of COPD patients.

CETP Expression Protects Female Mice from Obesity-Induced Decline in Exercise Capacity.

PubMed

Cappel, David A; Lantier, Louise; Palmisano, Brian T; Wasserman, David H; Stafford, John M

2015-01-01

Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD). Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP) is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases muscle glycolysis in fasting and protects against insulin resistance with high-fat diet (HFD) feeding in female but not male mice. Since glycolysis provides an important energy source for working muscle, we aimed to define if CETP expression protects against the decline in exercise capacity associated with obesity. We measured exercise capacity in female mice that were fed a chow diet and then switched to a HFD. There was no difference in exercise capacity between lean, chow-fed CETP female mice and their non-transgenic littermates. Female CETP transgenic mice were relatively protected against the decline in exercise capacity caused by obesity compared to WT. Despite gaining similar fat mass after 6 weeks of HFD-feeding, female CETP mice showed a nearly two-fold increase in run distance compared to WT. After an additional 6 weeks of HFD-feeding, mice were subjected to a final exercise bout and muscle mitochondria were isolated. We found that improved exercise capacity in CETP mice corresponded with increased muscle mitochondrial oxidative capacity, and increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). These results suggest that CETP can protect against the obesity-induced impairment in exercise capacity and may be a target to improve exercise capacity in the context of obesity.

CETP Expression Protects Female Mice from Obesity-Induced Decline in Exercise Capacity

PubMed Central

Cappel, David A.; Lantier, Louise; Palmisano, Brian T.; Wasserman, David H.; Stafford, John M.

2015-01-01

Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD). Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP) is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases muscle glycolysis in fasting and protects against insulin resistance with high-fat diet (HFD) feeding in female but not male mice. Since glycolysis provides an important energy source for working muscle, we aimed to define if CETP expression protects against the decline in exercise capacity associated with obesity. We measured exercise capacity in female mice that were fed a chow diet and then switched to a HFD. There was no difference in exercise capacity between lean, chow-fed CETP female mice and their non-transgenic littermates. Female CETP transgenic mice were relatively protected against the decline in exercise capacity caused by obesity compared to WT. Despite gaining similar fat mass after 6 weeks of HFD-feeding, female CETP mice showed a nearly two-fold increase in run distance compared to WT. After an additional 6 weeks of HFD-feeding, mice were subjected to a final exercise bout and muscle mitochondria were isolated. We found that improved exercise capacity in CETP mice corresponded with increased muscle mitochondrial oxidative capacity, and increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). These results suggest that CETP can protect against the obesity-induced impairment in exercise capacity and may be a target to improve exercise capacity in the context of obesity. PMID:26313355

Resistance to Aerobic Exercise Training Causes Metabolic Dysfunction and Reveals Novel Exercise-Regulated Signaling Networks

PubMed Central

Lessard, Sarah J.; Rivas, Donato A.; Alves-Wagner, Ana B.; Hirshman, Michael F.; Gallagher, Iain J.; Constantin-Teodosiu, Dumitru; Atkins, Ryan; Greenhaff, Paul L.; Qi, Nathan R.; Gustafsson, Thomas; Fielding, Roger A.; Timmons, James A.; Britton, Steven L.; Koch, Lauren G.; Goodyear, Laurie J.

2013-01-01

Low aerobic exercise capacity is a risk factor for diabetes and a strong predictor of mortality, yet some individuals are “exercise-resistant” and unable to improve exercise capacity through exercise training. To test the hypothesis that resistance to aerobic exercise training underlies metabolic disease risk, we used selective breeding for 15 generations to develop rat models of low and high aerobic response to training. Before exercise training, rats selected as low and high responders had similar exercise capacities. However, after 8 weeks of treadmill training, low responders failed to improve their exercise capacity, whereas high responders improved by 54%. Remarkably, low responders to aerobic training exhibited pronounced metabolic dysfunction characterized by insulin resistance and increased adiposity, demonstrating that the exercise-resistant phenotype segregates with disease risk. Low responders had impaired exercise-induced angiogenesis in muscle; however, mitochondrial capacity was intact and increased normally with exercise training, demonstrating that mitochondria are not limiting for aerobic adaptation or responsible for metabolic dysfunction in low responders. Low responders had increased stress/inflammatory signaling and altered transforming growth factor-β signaling, characterized by hyperphosphorylation of a novel exercise-regulated phosphorylation site on SMAD2. Using this powerful biological model system, we have discovered key pathways for low exercise training response that may represent novel targets for the treatment of metabolic disease. PMID:23610057

Home-based telerehabilitation via real-time videoconferencing improves endurance exercise capacity in patients with COPD: The randomized controlled TeleR Study.

PubMed

Tsai, Ling Ling Y; McNamara, Renae J; Moddel, Chloe; Alison, Jennifer A; McKenzie, David K; McKeough, Zoe J

2017-05-01

Telerehabilitation has the potential to increase access to pulmonary rehabilitation (PR) for patients with COPD who have difficulty accessing centre-based PR due to poor mobility, lack of transport and cost of travel. We aimed to determine the effect of supervised, home-based, real-time videoconferencing telerehabilitation on exercise capacity, self-efficacy, health-related quality of life (HRQoL) and physical activity in patients with COPD compared with usual care without exercise training. Patients with COPD were randomized to either a supervised home-based telerehabilitation group (TG) that received exercise training three times a week for 8 weeks or a control group (CG) that received usual care without exercise training. Outcomes were measured at baseline and following the intervention. Thirty-six out of 37 participants (mean ± SD age = 74 ± 8 years, forced expiratory volume in 1 s (FEV 1 ) = 64 ± 21% predicted) completed the study. Compared with the CG, the TG showed a statistically significant increase in endurance shuttle walk test time (mean difference = 340 s (95% CI: 153-526, P < 0.001)), an increase in self-efficacy (mean difference = 8 points (95% CI: 2-14, P < 0.007)), a trend towards a statistically significant increase in the Chronic Respiratory Disease Questionnaire total score (mean difference = 8 points (95% CI: -1 to 16, P = 0.07)) and no difference in physical activity (mean difference = 475 steps per day (95% CI: -200 to 1151, P = 0.16)). This study showed that telerehabilitation improved endurance exercise capacity and self-efficacy in patients with COPD when compared with usual care. © 2016 Asian Pacific Society of Respirology.

Effect of Body Mass Index on Exercise Capacity in Patients With Hypertrophic Cardiomyopathy.

PubMed

Larsen, Carolyn M; Ball, Caroline A; Hebl, Virginia B; Ong, Kevin C; Siontis, Konstantinos C; Olson, Thomas P; Ackerman, Michael J; Ommen, Steve R; Allison, Thomas G; Geske, Jeffrey B

2018-01-01

The objective of this study was to evaluate the relation between body mass index (BMI), exercise capacity, and symptoms in patients with hypertrophic cardiomyopathy (HC) and to utilize results of cardiopulmonary exercise tests (CPX) and transthoracic echocardiograms to understand the mechanism(s) of reduced exercise capacity across body mass index groups. Over a 6-year period, 510 consecutive patients with HC seen at a tertiary referral center underwent (CPX) and a transthoracic echocardiogram. Increasing BMI was associated with decreased exercise capacity as assessed by peak VO 2 (ml/kg/min). However, the prevalence of cardiac impairment did not vary by BMI group. In conclusion, these findings suggest that in some patients with hypertrophic cardiomyopathy, cardiac impairment is not the primary cause of exercise limitation and weight loss may result in improved exercise capacity. Copyright © 2017 Elsevier Inc. All rights reserved.

Left ventricular markers of global dyssynchrony predict limited exercise capacity in heart failure, but not in patients with preserved ejection fraction

PubMed Central

2012-01-01

Background The aim of this study was to prospectively examine echocardiographic parameters that correlate and predict functional capacity assessed by 6 min walk test (6-MWT) in patients with heart failure (HF), irrespective of ejection fraction (EF). Methods In 147 HF patients (mean age 61 ± 11 years, 50.3% male), a 6-MWT and an echo-Doppler study were performed in the same day. Global LV dyssynchrony was indirectly assessed by total isovolumic time - t-IVT [in s/min; calculated as: 60 – (total ejection time + total filling time)], and Tei index (t-IVT/ejection time). Patients were divided into two groups based on the 6-MWT distance (Group I: ≤300 m and Group II: >300 m), and also in two groups according to EF (Group A: LVEF ≥ 45% and Group B: LVEF < 45%). Results In the cohort of patients as a whole, the 6-MWT correlated with t-IVT (r = −0.49, p < 0.001) and Tei index (r = −0.43, p < 0.001) but not with any of the other clinical or echocardiographic parameters. Group I had lower hemoglobin level (p = 0.02), lower EF (p = 0.003), larger left atrium (p = 0.02), thicker interventricular septum (p = 0.02), lower A wave (p = 0.01) and lateral wall late diastolic myocardial velocity a’ (p = 0.047), longer isovolumic relaxation time (r = 0.003) and longer t-IVT (p = 0.03), compared with Group II. In the patients cohort as a whole, only t-IVT ratio [1.257 (1.071-1.476), p = 0.005], LV EF [0.947 (0.903-0.993), p = 0.02], and E/A ratio [0.553 (0.315-0.972), p = 0.04] independently predicted poor 6-MWT performance (<300 m) in multivariate analysis. None of the echocardiographic measurements predicted exercise tolerance in HFpEF. Conclusion In patients with HF, the limited exercise capacity, assessed by 6-MWT, is related mostly to severity of global LV dyssynchrony, more than EF or raised filling pressures. The lack of exercise predictors in HFpEF reflects its multifactorial pathophysiology. PMID:22966942

[Follow-up of patients with good exercise capacity in stress test with myocardial single-photon emission computed tomography (SPECT)].

PubMed

González, Javiera; Prat, Hernán; Swett, Eduardo; Berrocal, Isabel; Fernández, René; Zhindon, Juan Pablo; Castro, Ariel; Massardo, Teresa

2015-11-01

The evaluation of coronary artery disease (CAD) can be performed with stress test and myocardial SPECT tomography. To assess the predictive value of myocardial SPECT using stress test for cardiovascular events in patients with good exercise capacity. We included 102 males aged 56 ± 10 years and 19 females aged 52 ± 10 years, all able to achieve 10 METs and ≥ 85% of the theoretical maximum heart rate and at least 8 min in their stress test with gated 99mTc-sestamibi SPECT. Eighty two percent of patients were followed clinically for 33 ± 17 months. Sixty seven percent of patients were studied for CAD screening and the rest for known disease assessment. Treadmill stress test was negative in 75.4%; 37% of patients with moderate to severe Duke Score presented ischemia. Normal myocardial perfusion SPECT was observed in 70.2%. Reversible defects appeared in 24.8% of cases, which were of moderate or severe degree (> 10% left ventricular extension) in 56.6%. Only seven cases had coronary events after the SPECT. Two major (myocardial infarction and emergency coronary revascularization) and 5 minor events (elective revascularization) ere observed in the follow-up. In a multivariate analysis, SPECT ischemia was the only statistically significant parameter that increased the probability of having a major or minor event. Nearly a quarter of our patients with good exercise capacity demonstrated reversible defects in their myocardial perfusion SPECT. In the intermediate-term follow-up, a low rate of cardiac events was observed, being the isotopic ischemia the only significant predictive parameter.

Exercise capacity and muscle strength and risk of vascular disease and arrhythmia in 1.1 million young Swedish men: cohort study.

PubMed

Andersen, Kasper; Rasmussen, Finn; Held, Claes; Neovius, Martin; Tynelius, Per; Sundström, Johan

2015-09-16

To investigate the associations of exercise capacity and muscle strength in late adolescence with risk of vascular disease and arrhythmia. Cohort study. General population in Sweden. 1.1 million men who participated in mandatory military conscription between 1 August 1972 and 31 December 1995, at a median age of 18.2 years. Participants were followed until 31 December 2010. Associations between exercise capacity and muscle strength with risk of vascular disease and subgroups (ischaemic heart disease, heart failure, stroke, and cardiovascular death) and risk of arrhythmia and subgroups (atrial fibrillation or flutter, bradyarrhythmia, supraventricular tachycardia, and ventricular arrhythmia or sudden cardiac death). Maximum exercise capacity was estimated by the ergometer bicycle test, and muscle strength was measured as handgrip strength by a hand dynamometer. High exercise capacity or muscle strength was deemed as above the median level. During a median follow-up of 26.3 years, 26 088 vascular disease events and 17 312 arrhythmia events were recorded. Exercise capacity was inversely associated with risk of vascular disease and its subgroups. Muscle strength was also inversely associated with vascular disease risk, driven by associations of higher muscle strength with lower risk of heart failure and cardiovascular death. Exercise capacity had a U shaped association with risk of arrhythmia, driven by a direct association with risk of atrial fibrillation and a U shaped association with bradyarrhythmia. Higher muscle strength was associated with lower risk of arrhythmia (specifically, lower risk of bradyarrhythmia and ventricular arrhythmia). The combination of high exercise capacity and high muscle strength was associated with a hazard ratio of 0.67 (95% confidence interval 0.65 to 0.70) for vascular events and 0.92 (0.88 to 0.97) for arrhythmia compared with the combination of low exercise capacity and low muscle strength. Exercise capacity and muscle strength in late adolescence are independently and jointly associated with long term risk of vascular disease and arrhythmia. The health benefit of lower risk of vascular events with higher exercise capacity was not outweighed by higher risk of arrhythmia. © Andersen et al 2015.

Aerobic exercise deconditioning and countermeasures during bed rest.

PubMed

Lee, Stuart M C; Moore, Alan D; Everett, Meghan E; Stenger, Michael B; Platts, Steven H

2010-01-01

Bed rest is a well-accepted model for spaceflight in which the physiologic adaptations, particularly in the cardiovascular system, are studied and potential countermeasures can be tested. Bed rest without countermeasures results in reduced aerobic capacity and altered submaximal exercise responses. Aerobic endurance and factors which may impact prolonged exercise, however, have not been well studied. The initial loss of aerobic capacity is rapid, occurring in parallel with the loss of plasma volume. Thereafter, the reduction in maximal aerobic capacity proceeds more slowly and is influenced by central and peripheral adaptation. Exercise capacity can be maintained during bed rest and may be improved during recovery with appropriate countermeasures. Plasma volume restoration, resistive exercise, orthostatic stress, aerobic exercise, and aerobic exercise plus orthostatic stress all have been tested with varying levels of success. However, the optimal combination of elements-exercise modality, intensity, duration, muscle groups exercised and frequency of aerobic exercise, orthostatic stress, and supplementary resistive or anaerobic exercise training-has not been systematically evaluated. Currently, frequent (at least 3 days per week) bouts of intense exercise (interval-style and near maximal) with orthostatic stress appears to be the most efficacious method to protect aerobic capacity during bed rest. Further refinement of protocols and countermeasure hardware may be necessary to insure the success of countermeasures in the unique environment of space.

Left ventricular assist device: exercise capacity evolution and rehabilitation added value.

PubMed

Lamotte, Michel X; Chimenti, Sara; Deboeck, Gael; Gillet, Alexis; Kacelenenbogen, Raymond; Strapart, Jonathan; Vandeneynde, Frédéric; Van Nooten, Guido; Antoine, Martine

2018-06-01

With more than 15,000 implanted patients worldwide and a survival rate of 80% at 1-year and 59% at 5-years, left ventricular assist device (LVAD) implantation has become an interesting strategy in the management of heart failure patients who are resistant to other kinds of treatment. There are limited data in the literature on the change over time of exercise capacity in LVAD patients, as well as limited knowledge about the beneficial effects that rehabilitation might have on these patients. Therefore, the aim of our study was to evaluate the evolution of exercise capacity on a cohort of patients implanted with the same device (HeartWare © ) and to analyse the potential impact of rehabilitation. Sixty-two patients implanted with a LVAD between June 2011 and June 2015 were screened. Exercise capacity was evaluated by cardiopulmonary exercise testing at 6 weeks, 6 and 12 months after implantation. We have observed significant differences in the exercise capacity and evolution between the trained and non-trained patients. Some of the trained patients nearly normalised their exercise capacity at the end of the rehabilitation programme. Exercise capacity of patient implanted with a HeartWare © LVAD increased in the early period after implantation. Rehabilitation allowed implanted patients to have a significantly better evolution compared to non-rehabilitated patients.

Effects of exercise training in patients with idiopathic pulmonary arterial hypertension.

PubMed

de Man, F S; Handoko, M L; Groepenhoff, H; van 't Hul, A J; Abbink, J; Koppers, R J H; Grotjohan, H P; Twisk, J W R; Bogaard, H-J; Boonstra, A; Postmus, P E; Westerhof, N; van der Laarse, W J; Vonk-Noordegraaf, A

2009-09-01

We determined the physiological effects of exercise training on exercise capacity and quadriceps muscle function in patients with idiopathic pulmonary arterial hypertension (iPAH). In total, 19 clinically stable iPAH patients (New York Heart Association II-III) underwent a supervised exercise training programme for the duration of 12 weeks. Maximal capacity, endurance capacity and quadriceps function were assessed at baseline and after 12 weeks. In 12 patients, serial quadriceps muscle biopsies were obtained. 6-min walk distance and peak exercise capacity did not change after training. However, endurance capacity improved significantly after training, demonstrated by a shift of the anaerobic threshold to a higher workload (from 32+/-5 to 46+/-6 W; p = 0.003) together with an increase in exercise endurance time (p<0.001). Moreover, exercise training increased quadriceps strength by 13% (p = 0.005) and quadriceps endurance by 34% (p = 0.001). Training enhanced aerobic capacity of the quadriceps, by increasing capillarisation (1.36+/-0.10 to 1.78+/-0.13 capillaries per muscle fibre; p<0.001) and oxidative enzyme activity, especially of the type-I (slow) muscle fibres. No changes were found in cross-sectional area and fibre type distribution. Exercise training in iPAH improves exercise endurance and quadriceps muscle function, which is also reflected by structural changes of the quadriceps.

Exercise Capacity and the Obesity Paradox in Heart Failure: The FIT (Henry Ford Exercise Testing) Project.

PubMed

McAuley, Paul A; Keteyian, Steven J; Brawner, Clinton A; Dardari, Zeina A; Al Rifai, Mahmoud; Ehrman, Jonathan K; Al-Mallah, Mouaz H; Whelton, Seamus P; Blaha, Michael J

2018-05-03

To assess the influence of exercise capacity and body mass index (BMI) on 10-year mortality in patients with heart failure (HF) and to synthesize these results with those of previous studies. This large biracial sample included 774 men and women (mean age, 60±13 years; 372 [48%] black) with a baseline diagnosis of HF from the Henry Ford Exercise Testing (FIT) Project. All patients completed a symptom-limited maximal treadmill stress test from January 1, 1991, through May 31, 2009. Patients were grouped by World Health Organization BMI categories for Kaplan-Meier survival analyses and stratified by exercise capacity (<4 and ≥4 metabolic equivalents [METs] of task). Associations of BMI and exercise capacity with all-cause mortality were assessed using multivariable-adjusted Cox proportional hazards models. During a mean follow-up of 10.1±4.6 years, 380 patients (49%) died. Kaplan-Meier survival plots revealed a significant positive association between BMI category and survival for exercise capacity less than 4 METs (log-rank, P=.05), but not greater than or equal to 4 METs (P=.76). In the multivariable-adjusted models, exercise capacity (per 1 MET) was inversely associated, but BMI was not associated, with all-cause mortality (hazard ratio, 0.89; 95% CI, 0.85-0.94; P<.001 and hazard ratio, 0.99; 95% CI, 0.97-1.01; P=.16, respectively). Maximal exercise capacity modified the relationship between BMI and long-term survival in patients with HF, upholding the presence of an exercise capacity-obesity paradox dichotomy as observed over the short-term in previous studies. Copyright © 2018 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Why don't you exercise? Development of the Amotivation Toward Exercise Scale among older inactive individuals.

PubMed

Vlachopoulos, Symeon P; Gigoudi, Maria A

2008-07-01

This article reports on the development and initial validation of the Amotivation Toward Exercise Scale (ATES), which reflects a taxonomy of older adults' reasons to refrain from exercise. Drawing on work by Pelletier, Dion, Tuson, and Green-Demers (1999) and Legault, Green-Demers, and Pelletier (2006), these dimensions were the outcome beliefs, capacity beliefs, effort beliefs, and value amotivation beliefs toward exercise. The results supported a 4-factor correlated model that fit the data better than either a unidimensional model or a 4-factor uncorrelated model or a hierarchical model with strong internal reliability for all the subscales. Evidence also emerged for the discriminant validity of the subscale scores. Furthermore, the predictive validity of the subscale scores was supported, and satisfactory measurement invariance was demonstrated across the calibration and validation samples, supporting the generalizability of the scale's measurement properties.

Effects of detraining on anthropometry, aerobic capacity and functional ability in adults with Down syndrome.

PubMed

Boer, P H

2018-01-01

Structured exercise has shown to improve parameters of functional fitness in adults with Down syndrome (DS). However, few, if any, continue to exercise after exercise intervention studies. Consequently, the purpose of this study was to determine the effects of detraining on anthropometry, aerobic capacity and functional ability of adults with DS. In a previous study, forty-two participants either performed 12 weeks of interval training, continuous aerobic training or no training (CON). After 3 months of detraining, the same participants were tested again for anthropometry, aerobic capacity, leg strength and functional ability. Significant reductions in maximal aerobic capacity, time to exhaustion and both functional test items were reported for both exercise groups compared to CON (p < .05). No significant differences were reported between the exercise groups concerning aerobic and functional capacity reductions. Detraining occurred significantly in both exercise groups regarding parameters associated with aerobic and functional capacity. © 2017 John Wiley & Sons Ltd.

Exercise hypoxaemia as a predictor of pulmonary hypertension in COPD patients without severe resting hypoxaemia.

PubMed

Nakahara, Yoshio; Taniguchi, Hiroyuki; Kimura, Tomoki; Kondoh, Yasuhiro; Arizono, Shinichi; Nishimura, Koichi; Sakamoto, Koji; Ito, Satoru; Ando, Masahiko; Hasegawa, Yoshinori

2017-01-01

Pulmonary hypertension (PH) in COPD is associated with morbidity and mortality. Previous studies showed a relationship between resting hypoxaemia and PH, but little is known about the relationship between exercise hypoxaemia and PH in COPD without resting hypoxaemia. A retrospective observational study of COPD patients without resting hypoxaemia was conducted to evaluate the relationships between exercise hypoxaemia and pulmonary haemodynamics. Clinical characteristics, pulmonary function, blood gas analysis, 6-min walk distance (6MWD) and oxygen saturation of peripheral artery (SpO 2 ) at the end of the 6-min walk test (6MWT) were reviewed. Correlation analysis and stepwise regression analysis were performed to identify the predictor of mean pulmonary artery pressure (mPAP). Eighty-four consecutive patients with a mean predicted forced expiratory volume in 1 s (FEV 1 ) of 47 ± 21% were evaluated. In univariate analysis, mPAP had negative correlations with age (r = -0.27, P < 0.05), arterial partial pressure of oxygen (PaO 2 , r = -0.24, P < 0.05), % predicted forced vital capacity (FVC, r = -0.28, P < 0.05), % predicted FEV 1 (r = -0.40, P < 0.001), FEV 1 /FVC ratio (r = -0.33, P < 0.005), % predicted diffusion capacity for carbon monoxide (DL CO , r = -0.40, P < 0.001), 6MWD (r = -0.40, P < 0.001) and SpO 2 at the end of the 6MWT (r = -0.74, P < 0.001). In stepwise regression analysis, SpO 2 at the end of the 6MWT and 6MWD remained as independent predictors of mPAP (R 2  = 0.60). In receiver operating characteristic (ROC) analysis, SpO 2 at the end of the 6MWT presented an area under the curve of 0.896 for the prediction of PH, with a sensitivity of 0.86 and specificity of 0.84 for the cut-off point of 81%. In addition to 6MWD, exercise hypoxaemia indicates PH in patients with COPD without resting hypoxaemia. © 2016 Asian Pacific Society of Respirology.

The relationship between exercise capacity and masked hypertension in sedentary patients with diabetes mellitus.

PubMed

Akilli, Hakan; Kayrak, Mehmet; Arıbas, Alpay; Tekinalp, Mehmet; Ayhan, Selim Suzi; Gündüz, Mehmet; Alibasic, Hajrudin; Altunbas, Gokhan; Yazıcı, Mehmet

2014-01-01

Although exaggerated blood pressure responses (EBPR) to exercise have been related to future hypertension and masked hypertension (MHT), the relationship between exercise capacity and MHT remains unclear. A sedentary life style has been related to increased cardiovascular mortality, diabetes mellitus (DM), and hypertension. In this study, we aimed to examine the relationship between exercise capacity and MHT in sedentary patients with DM. This study included 85 sedentary and normotensive patients with DM. Each patient's daily physical activity level was assessed according to the INTERHEART study. All patients underwent an exercise treadmill test, and exercise duration and capacity were recorded. Blood pressure (BP) was recorded during all exercise stages and BP values ≥ 200/110 mmHg were accepted as EBPR. MHT was diagnosed in patients having an office BP <140/90 mmHg and a daytime ambulatory BP >135/85 mmHg. Patients were divided into two groups according to their ambulatory BP monitoring (MHT and normotensive group). The prevalence of MHT was 28.2%. Exercise duration and capacity were lower in the MHT group than in the normotensive group (p<0.05) and were negatively correlated with age, HbA1c, mean daytime BP, and mean 24 hour BP. Peak exercise systolic BP and the frequency of EBPR were both increased in the MHT group (25.0% and 8.1%, respectively, p=0.03). According to a multivariate regression, exercise capacity (OR: 0.61, CI95%: 0.39-0.95, p=0.03), EBPR (OR: 9.45, CI95%: 1.72-16.90, p=0.01), and the duration of DM (OR: 0.84, CI95%: 0.71-0.96, p=0.03) were predictors of MHT. Exercise capacity, EBPR, and the duration of DM were predictors of MHT in sedentary subjects with DM.

Self-reported quality of life before and after aerobic exercise training in individuals with hypertension: a randomised-controlled trial.

PubMed

Maruf, Fatai A; Akinpelu, Aderonke O; Salako, Babatunde L

2013-07-01

The Effects of Aerobic Exercise Training (AET) on self-reported Quality of Life (QoL) in people with hypertension have been previously documented. However, data on black populations, especially from Africa, seem not to be available. This study investigated the effects of AET on QoL and exercise capacity in Nigerians on treatment for essential hypertension. This randomised-controlled trial involved newly diagnosed individuals, with mild-to-moderate essential hypertension randomly assigned to antihypertensive drugs (ADs) alone (control: n = 60) and AET+ADs (exercise: n = 60) groups. The study lasted for 12 weeks. QoL was measured using the World Health Organization QoL Short Form (WHOQoL-BREF) and exercise capacity was assessed using the Rockport Fitness Walk Test pre- and post-study. Physical health, psychological health, and social relationships domains of QoL improved significantly in the exercise and control groups post-intervention. The environment domain of QoL and exercise capacity improved significantly in only the exercise group. There were larger improvements in the physical health, psychological health, and environment domains of QoL, and exercise capacity in the exercise group. Aerobic exercise improves QoL and exercise capacity in individuals with essential hypertension. © 2013 The Authors. Applied Psychology: Health and Well-Being © 2013 The International Association of Applied Psychology.

Restoration of Muscle Glycogen and Functional Capacity: Role of Post-Exercise Carbohydrate and Protein Co-Ingestion

PubMed Central

Alghannam, Abdullah F.; Betts, James A.

2018-01-01

The importance of post-exercise recovery nutrition has been well described in recent years, leading to its incorporation as an integral part of training regimes in both athletes and active individuals. Muscle glycogen depletion during an initial prolonged exercise bout is a main factor in the onset of fatigue and so the replenishment of glycogen stores may be important for recovery of functional capacity. Nevertheless, nutritional considerations for optimal short-term (3–6 h) recovery remain incompletely elucidated, particularly surrounding the precise amount of specific types of nutrients required. Current nutritional guidelines to maximise muscle glycogen availability within limited recovery are provided under the assumption that similar fatigue mechanisms (i.e., muscle glycogen depletion) are involved during a repeated exercise bout. Indeed, recent data support the notion that muscle glycogen availability is a determinant of subsequent endurance capacity following limited recovery. Thus, carbohydrate ingestion can be utilised to influence the restoration of endurance capacity following exhaustive exercise. One strategy with the potential to accelerate muscle glycogen resynthesis and/or functional capacity beyond merely ingesting adequate carbohydrate is the co-ingestion of added protein. While numerous studies have been instigated, a consensus that is related to the influence of carbohydrate-protein ingestion in maximising muscle glycogen during short-term recovery and repeated exercise capacity has not been established. When considered collectively, carbohydrate intake during limited recovery appears to primarily determine muscle glycogen resynthesis and repeated exercise capacity. Thus, when the goal is to optimise repeated exercise capacity following short-term recovery, ingesting carbohydrate at an amount of ≥1.2 g kg body mass−1·h−1 can maximise muscle glycogen repletion. The addition of protein to carbohydrate during post-exercise recovery may be beneficial under circumstances when carbohydrate ingestion is sub-optimal (≤0.8 g kg body mass−1·h−1) for effective restoration of muscle glycogen and repeated exercise capacity. PMID:29473893

[Evaluation of exercise capacity in pulmonary arterial hypertension].

PubMed

Demir, Rengin; Küçükoğlu, Mehmet Serdar

2010-12-01

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by increased pulmonary vascular resistance that leads to right ventricular failure. The most common clinical features of PAH are dyspnea and exercise intolerance. Measurement of exercise capacity is of considerable importance for the assessment of disease severity as well as routine monitoring of disease. Maximal, symptom-limited, cardiopulmonary exercise test (CPET) is the gold standard for the evaluation of exercise capacity, whereby functions of several systems involved in exercise can be assessed, including cardiovascular, respiratory, and metabolic systems. However, in order to derive the most useful diagnostic information on physiologic limitations to exercise, CPET requires maximal effort of the patient, which can be difficult and risky for some severely ill patients. Moreover, it requires specific exercise equipment and measurement systems, and experienced and trained personnel. Thus, routine clinical use of CPET to assess exercise capacity in patients with PAH may not always be feasible. A practical and simple alternative to CPET to determine exercise capacity is the 6-minute walk test (6MWT). It is simple to perform, safe, and reproducible. In contrast to CPET, the 6MWT reflects a submaximal level of exertion that is more consistent with the effort required for daily physical activities. This review focuses on the role of CPET and 6MWT in patients with PAH.

The relationship of aerobic capacity, anaerobic peak power and experience to performance in CrossFit exercise.

PubMed

Bellar, D; Hatchett, A; Judge, L W; Breaux, M E; Marcus, L

2015-11-01

CrossFit is becoming increasingly popular as a method to increase fitness and as a competitive sport in both the Unites States and Europe. However, little research on this mode of exercise has been performed to date. The purpose of the present investigation involving experienced CrossFit athletes and naïve healthy young men was to investigate the relationship of aerobic capacity and anaerobic power to performance in two representative CrossFit workouts: the first workout was 12 minutes in duration, and the second was based on the total time to complete the prescribed exercise. The participants were 32 healthy adult males, who were either naïve to CrossFit exercise or had competed in CrossFit competitions. Linear regression was undertaken to predict performance on the first workout (time) with age, group (naïve or CrossFit athlete), VO2max and anaerobic power, which were all significant predictors (p < 0.05) in the model. The second workout (repetitions), when examined similarly using regression, only resulted in CrossFit experience as a significant predictor (p < 0.05). The results of the study suggest that a history of participation in CrossFit competition is a key component of performance in CrossFit workouts which are representative of those performed in CrossFit, and that, in at least one these workouts, aerobic capacity and anaerobic power are associated with success.

The relationship of aerobic capacity, anaerobic peak power and experience to performance in CrossFit exercise

PubMed Central

Hatchett, A; Judge, LW; Breaux, ME; Marcus, L

2015-01-01

CrossFit is becoming increasingly popular as a method to increase fitness and as a competitive sport in both the Unites States and Europe. However, little research on this mode of exercise has been performed to date. The purpose of the present investigation involving experienced CrossFit athletes and naïve healthy young men was to investigate the relationship of aerobic capacity and anaerobic power to performance in two representative CrossFit workouts: the first workout was 12 minutes in duration, and the second was based on the total time to complete the prescribed exercise. The participants were 32 healthy adult males, who were either naïve to CrossFit exercise or had competed in CrossFit competitions. Linear regression was undertaken to predict performance on the first workout (time) with age, group (naïve or CrossFit athlete), VO2max and anaerobic power, which were all significant predictors (p < 0.05) in the model. The second workout (repetitions), when examined similarly using regression, only resulted in CrossFit experience as a significant predictor (p < 0.05). The results of the study suggest that a history of participation in CrossFit competition is a key component of performance in CrossFit workouts which are representative of those performed in CrossFit, and that, in at least one these workouts, aerobic capacity and anaerobic power are associated with success. PMID:26681834

Effects of lower extremity injuries on aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function in high school soccer players.

PubMed

Ko, Kwang-Jun; Ha, Gi-Chul; Kim, Dong-Woo; Kang, Seol-Jung

2017-10-01

[Purpose] The study investigated the effects of lower extremity injuries on aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function in high school soccer players. [Subjects and Methods] The study assessed U High School soccer players (n=40) in S area, South Korea, divided into 2 groups: a lower extremity injury group (n=16) comprising those with knee and ankle injuries and a control group (n=24) without injury. Aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function were compared and analyzed. [Results] Regarding the aerobic exercise capacity test, significant differences were observed in maximal oxygen uptake and anaerobic threshold between both groups. For the anaerobic power test, no significant difference was observed in peak power and average power between the groups; however, a significant difference in fatigue index was noted. Regarding the knee isokinetic muscular test, no significant difference was noted in knee flexion, extension, and flexion/extension ratio between both groups. [Conclusion] Lower extremity injury was associated with reduced aerobic exercise capacity and a higher fatigue index with respect to anaerobic exercise capacity. Therefore, it seems necessary to establish post-injury training programs that improve aerobic and anaerobic exercise capacity for soccer players who experience lower extremity injury.

Adrenergic Receptor Polymorphism and Maximal Exercise Capacity after Orthotopic Heart Transplantation.

PubMed

Métrich, Mélanie; Mehmeti, Fortesa; Feliciano, Helene; Martin, David; Regamey, Julien; Tozzi, Piergiorgio; Meyer, Philippe; Hullin, Roger

Maximal exercise capacity after heart transplantion (HTx) is reduced to the 50-70% level of healthy controls when assessed by cardiopulmonary exercise testing (CPET) despite of normal left ventricular function of the donor heart. This study investigates the role of donor heart β1 and β2- adrenergic receptor (AR) polymorphisms for maximal exercise capacity after orthotopic HTx. CPET measured peak VO2 as outcome parameter for maximal exercise in HTx recipients ≥9 months and ≤4 years post-transplant (n = 41; mean peak VO2: 57±15% of predicted value). Donor hearts were genotyped for polymorphisms of the β1-AR (Ser49Gly, Arg389Gly) and the β2-AR (Arg16Gly, Gln27Glu). Circumferential shortening of the left ventricle was measured using magnetic resonance based CSPAMM tagging. Peak VO2 was higher in donor hearts expressing the β1-Ser49Ser alleles when compared with β1-Gly49 carriers (60±15% vs. 47±10% of the predicted value; p = 0.015), and by trend in cardiac allografts with the β1-AR Gly389Gly vs. β1-Arg389 (61±15% vs. 54±14%, p = 0.093). Peak VO2 was highest for the haplotype Ser49Ser-Gly389, and decreased progressively for Ser49Ser-Arg389Arg > 49Gly-389Gly > 49Gly-Arg389Arg (adjusted R2 = 0.56, p = 0.003). Peak VO2 was not different for the tested β2-AR polymorphisms. Independent predictors of peak VO2 (adjusted R2 = 0.55) were β1-AR Ser49Gly SNP (p = 0.005), heart rate increase (p = 0.016), and peak systolic blood pressure (p = 0.031). Left ventricular (LV) motion kinetics as measured by cardiac MRI CSPAMM tagging at rest was not different between carriers and non-carriers of the β1-AR Gly49allele. Similar LV cardiac motion kinetics at rest in donor hearts carrying either β1-AR Gly49 or β1-Ser49Ser variant suggests exercise-induced desensitization and down-regulation of the β1-AR Gly49 variant as relevant pathomechanism for reduced peak VO2 in β1-AR Gly49 carriers.

Trained humans can exercise safely in extreme dry heat when drinking water ad libitum.

PubMed

Nolte, Heinrich W; Noakes, Timothy D; Van Vuuren, Bernard

2011-09-01

Guidelines to establish safe environmental exercise conditions are partly based on thermal prescriptive zones. Yet there are reports of self-paced human athletic performances in extreme heat. Eighteen participants undertook a 25-km route march in a dry bulb temperature reaching 44.3°C. The mean (± s) age of the participants was 26.0 ± 3.7 years. Their mean ad libitum water intake was 1264 ± 229 mL · h(-1). Predicted sweat rate was 1789 ± 267 mL · h(-1). Despite an average body mass loss of 2.73 ± 0.98 kg, plasma osmolality and serum sodium concentration did not change significantly during exercise. Total body water fell 1.47 kg during exercise. However, change in body mass did not accurately predict changes in total body water as a 1:1 ratio. There was a significant relationship (negative slope) between post-exercise serum sodium concentration and changes in both body mass and percent total body water. There was no relationship between percent body mass loss and peak exercise core temperature (39 ± 0.9°C) or exercise time. We conclude that participants maintained plasma osmolality, serum sodium concentration, and safe core temperatures by (1) adopting a pacing strategy, (2) high rates of ad libitum water intake, and (3) by a small reduction in total body water to maintain serum sodium concentration. Our findings support the hypothesis that humans are the mammals with the greatest capacity for exercising in extreme heat.

Modeling the expenditure and reconstitution of work capacity above critical power.

PubMed

Skiba, Philip Friere; Chidnok, Weerapong; Vanhatalo, Anni; Jones, Andrew M

2012-08-01

The critical power (CP) model includes two constants: the CP and the W' [P = (W' / t) + CP]. The W' is the finite work capacity available above CP. Power output above CP results in depletion of the W' complete depletion of the W' results in exhaustion. Monitoring the W' may be valuable to athletes during training and competition. Our purpose was to develop a function describing the dynamic state of the W' during intermittent exercise. After determination of V˙O(2max), CP, and W', seven subjects completed four separate exercise tests on a cycle ergometer on different days. Each protocol comprised a set of intervals: 60 s at a severe power output, followed by 30-s recovery at a lower prescribed power output. The intervals were repeated until exhaustion. These data were entered into a continuous equation predicting balance of W' remaining, assuming exponential reconstitution of the W'. The time constant was varied by an iterative process until the remaining modeled W' = 0 at the point of exhaustion. The time constants of W' recharge were negatively correlated with the difference between sub-CP recovery power and CP. The relationship was best fit by an exponential (r = 0.77). The model-predicted W' balance correlated with the temporal course of the rise in V˙O(2) (r = 0.82-0.96). The model accurately predicted exhaustion of the W' in a competitive cyclist during a road race. We have developed a function to track the dynamic state of the W' during intermittent exercise. This may have important implications for the planning and real-time monitoring of athletic performance.

Perfusion Scintigraphy and Patient Selection for Lung Volume Reduction Surgery

PubMed Central

Chandra, Divay; Lipson, David A.; Hoffman, Eric A.; Hansen-Flaschen, John; Sciurba, Frank C.; DeCamp, Malcolm M.; Reilly, John J.; Washko, George R.

2010-01-01

Rationale: It is unclear if lung perfusion can predict response to lung volume reduction surgery (LVRS). Objectives: To study the role of perfusion scintigraphy in patient selection for LVRS. Methods: We performed an intention-to-treat analysis of 1,045 of 1,218 patients enrolled in the National Emphysema Treatment Trial who were non–high risk for LVRS and had complete perfusion scintigraphy results at baseline. The median follow-up was 6.0 years. Patients were classified as having upper or non–upper lobe–predominant emphysema on visual examination of the chest computed tomography and high or low exercise capacity on cardiopulmonary exercise testing at baseline. Low upper zone perfusion was defined as less than 20% of total lung perfusion distributed to the upper third of both lungs as measured on perfusion scintigraphy. Measurements and Main Results: Among 284 of 1,045 patients with upper lobe–predominant emphysema and low exercise capacity at baseline, the 202 with low upper zone perfusion had lower mortality with LVRS versus medical management (risk ratio [RR], 0.56; P = 0.008) unlike the remaining 82 with high perfusion where mortality was unchanged (RR, 0.97; P = 0.62). Similarly, among 404 of 1,045 patients with upper lobe–predominant emphysema and high exercise capacity, the 278 with low upper zone perfusion had lower mortality with LVRS (RR, 0.70; P = 0.02) unlike the remaining 126 with high perfusion (RR, 1.05; P = 1.00). Among the 357 patients with non–upper lobe–predominant emphysema (75 with low and 282 with high exercise capacity) there was no improvement in survival with LVRS and measurement of upper zone perfusion did not contribute new prognostic information. Conclusions: Compared with optimal medical management, LVRS reduces mortality in patients with upper lobe–predominant emphysema when there is low rather than high perfusion to the upper lung. PMID:20538961

Combination of exercise training and diet restriction normalizes limited exercise capacity and impaired skeletal muscle function in diet-induced diabetic mice.

PubMed

Suga, Tadashi; Kinugawa, Shintaro; Takada, Shingo; Kadoguchi, Tomoyasu; Fukushima, Arata; Homma, Tsuneaki; Masaki, Yoshihiro; Furihata, Takaaki; Takahashi, Masashige; Sobirin, Mochamad A; Ono, Taisuke; Hirabayashi, Kagami; Yokota, Takashi; Tanaka, Shinya; Okita, Koichi; Tsutsui, Hiroyuki

2014-01-01

Exercise training (EX) and diet restriction (DR) are essential for effective management of obesity and insulin resistance in diabetes mellitus. However, whether these interventions ameliorate the limited exercise capacity and impaired skeletal muscle function in diabetes patients remains unexplored. Therefore, we investigated the effects of EX and/or DR on exercise capacity and skeletal muscle function in diet-induced diabetic mice. Male C57BL/6J mice that were fed a high-fat diet (HFD) for 8 weeks were randomly assigned for an additional 4 weeks to 4 groups: control, EX, DR, and EX+DR. A lean group fed with a normal diet was also studied. Obesity and insulin resistance induced by a HFD were significantly but partially improved by EX or DR and completely reversed by EX+DR. Although exercise capacity decreased significantly with HFD compared with normal diet, it partially improved with EX and DR and completely reversed with EX+DR. In parallel, the impaired mitochondrial function and enhanced oxidative stress in the skeletal muscle caused by the HFD were normalized only by EX+DR. Although obesity and insulin resistance were completely reversed by DR with an insulin-sensitizing drug or a long-term intervention, the exercise capacity and skeletal muscle function could not be normalized. Therefore, improvement in impaired skeletal muscle function, rather than obesity and insulin resistance, may be an important therapeutic target for normalization of the limited exercise capacity in diabetes. In conclusion, a comprehensive lifestyle therapy of exercise and diet normalizes the limited exercise capacity and impaired muscle function in diabetes mellitus.

Physiological models to understand exercise fatigue and the adaptations that predict or enhance athletic performance.

PubMed

Noakes, T D

2000-06-01

A popular concept in the exercise sciences holds that fatigue develops during exercise of moderate to high intensity, when the capacity of the cardiorespiratory system to provide oxygen to the exercising muscles falls behind their demand inducing "anaerobic" metabolism. But this cardiovascular/anaerobic model is unsatisfactory because (i) a more rigorous analysis indicates that the first organ to be affected by anaerobiosis during maximal exercise would likely be the heart, not the skeletal muscles. This probability was fully appreciated by the pioneering exercise physiologists, A. V Hill, A. Bock and D. B. Dill, but has been systematically ignored by modern exercise physiologists; (ii) no study has yet definitely established the presence of either anaerobiosis, hypoxia or ischaemia in skeletal muscle during maximal exercise; (iii) the model is unable to explain why exercise terminates in a variety of conditions including prolonged exercise, exercise in the heat and at altitude, and in those with chronic diseases of the heart and lungs, without any evidence for skeletal muscle anaerobiosis, hypoxia or ischaemia, and before there is full activation of the total skeletal muscle mass, and (iv) cardiovascular and other measures believed to relate to skeletal muscle anaerobiosis, including the maximum oxygen consumption (VO2 max) and the "anaerobic threshold", are indifferent predictors of exercise capacity in athletes with similar abilities. This review considers four additional models that need to be considered when factors limiting either short duration, maximal or prolonged submaximal exercise are evaluated. These additional models are: (i) the energy supply/energy depletion model; (ii) the muscle power/muscle recruitment model; (iii) the biomechanical model and (iv) the psychological model. By reviewing features of these models, this review provides a broad overview of the physiological, metabolic and biomechanical factors that may limit exercise performance under different exercise conditions. A more complete understanding of fatigue during exercise, and the relevance of the adaptations that develop with training, requires that the potential relevance of each model to fatigue under different conditions of exercise must be considered.

Genetic Influences on Physiological and Subjective Responses to an Aerobic Exercise Session among Sedentary Adults

PubMed Central

Karoly, Hollis C.; Stevens, Courtney J.; Magnan, Renee E.; Harlaar, Nicole; Hutchison, Kent E.; Bryan, Angela D.

2012-01-01

Objective. To determine whether genetic variants suggested by the literature to be associated with physiology and fitness phenotypes predicted differential physiological and subjective responses to a bout of aerobic exercise among inactive but otherwise healthy adults. Method. Participants completed a 30-minute submaximal aerobic exercise session. Measures of physiological and subjective responding were taken before, during, and after exercise. 14 single nucleotide polymorphisms (SNPs) that have been previously associated with various exercise phenotypes were tested for associations with physiological and subjective response to exercise phenotypes. Results. We found that two SNPs in the FTO gene (rs8044769 and rs3751812) were related to positive affect change during exercise. Two SNPs in the CREB1 gene (rs2253206 and 2360969) were related to change in temperature during exercise and with maximal oxygen capacity (VO2 max). The SLIT2 SNP rs1379659 and the FAM5C SNP rs1935881 were associated with norepinephrine change during exercise. Finally, the OPRM1 SNP rs1799971 was related to changes in norepinephrine, lactate, and rate of perceived exertion (RPE) during exercise. Conclusion. Genetic factors influence both physiological and subjective responses to exercise. A better understanding of genetic factors underlying physiological and subjective responses to aerobic exercise has implications for development and potential tailoring of exercise interventions. PMID:22899923

Work, exercise, and space flight. 3: Exercise devices and protocols

NASA Technical Reports Server (NTRS)

Thornton, William

1989-01-01

Preservation of locomotor capacity by earth equivalent, exercise in space is the crucial component of inflight exercise. At this time the treadmill appears to be the only way possible to do this. Work is underway on appropriate hardware but this and a proposed protocol to reduce exercise time must be tested. Such exercise will preserve muscle, bone Ca(++) and cardiovascular-respiratory capacity. In addition, reasonable upper body exercise can be supplied by a new force generator/measurement system-optional exercise might include a rowing machine and bicycle ergometer. A subject centered monitoring-evaluation program will allow real time adjustments as required. Absolute protection for any astronaut will not be possible and those with hypertrophied capacities such as marathoners or weight lifters will suffer significant loss. However, the program described should return the crew to earth with adequate capacity of typical activity on earth including immediate ambulation and minimal recovery time and without permanent change. An understanding of the practical mechanics and biomechanics involved is essential to a solution of the problem.

Cardiorespiratory Fitness and Cognitive Function are Positively Related Among Participants with Mild and Subjective Cognitive Impairment.

PubMed

Stuckenschneider, Tim; Askew, Christopher David; Rüdiger, Stefanie; Cristina Polidori, Maria; Abeln, Vera; Vogt, Tobias; Krome, Andreas; Olde Rikkert, Marcel; Lawlor, Brian; Schneider, Stefan

2018-01-01

By 2030, about 74 million people will be diagnosed with dementia, and many more will experience subjective (SCI) or mild cognitive impairment (MCI). As physical inactivity has been identified to be a strong modifiable risk factor for dementia, exercise and physical activity (PA) may be important parameters to predict the progression from MCI to dementia, but might also represent disease trajectory modifying strategies for SCI and MCI. A better understanding of the relationship between activity, fitness, and cognitive function across the spectrum of MCI and SCI would provide an insight into the potential utility of PA and fitness as early markers, and treatment targets to prevent cognitive decline. 121 participants were stratified into three groups, late MCI (LMCI), early MCI (EMCI), and SCI based on the Montreal Cognitive Assessment (MoCA). Cognitive function assessments also included the Trail Making Test A+B, and a verbal fluency test. PA levels were evaluated with an interviewer-administered questionnaire (LAPAQ) and an activity monitor. An incremental exercise test was performed to estimate cardiorespiratory fitness and to determine exercise capacity relative to population normative data. ANCOVA revealed that LMCI subjects had the lowest PA levels (LAPAQ, p = 0.018; activity monitor, p = 0.041), and the lowest exercise capacity in relation to normative values (p = 0.041). Moreover, a modest correlation between MoCA and cardiorespiratory fitness (r = 0.25; p < 0.05) was found. These findings suggest that during the earliest stages of cognitive impairment PA and exercise capacity might present a marker for the risk of further cognitive decline. This finding warrants further investigation using longitudinal cohort studies.

Measurement of Exercise Tolerance before Surgery (METS) study: a protocol for an international multicentre prospective cohort study of cardiopulmonary exercise testing prior to major non-cardiac surgery.

PubMed

Wijeysundera, Duminda N; Pearse, Rupert M; Shulman, Mark A; Abbott, Tom E F; Torres, Elizabeth; Croal, Bernard L; Granton, John T; Thorpe, Kevin E; Grocott, Michael P W; Farrington, Catherine; Myles, Paul S; Cuthbertson, Brian H

2016-03-11

Preoperative functional capacity is considered an important risk factor for cardiovascular and other complications of major non-cardiac surgery. Nonetheless, the usual approach for estimating preoperative functional capacity, namely doctors' subjective assessment, may not accurately predict postoperative morbidity or mortality. 3 possible alternatives are cardiopulmonary exercise testing; the Duke Activity Status Index, a standardised questionnaire for estimating functional capacity; and the serum concentration of N-terminal pro-B-type natriuretic peptide (NT pro-BNP), a biomarker for heart failure and cardiac ischaemia. The Measurement of Exercise Tolerance before Surgery (METS) Study is a multicentre prospective cohort study of patients undergoing major elective non-cardiac surgery at 25 participating study sites in Australia, Canada, New Zealand and the UK. We aim to recruit 1723 participants. Prior to surgery, participants undergo symptom-limited cardiopulmonary exercise testing on a cycle ergometer, complete the Duke Activity Status Index questionnaire, undergo blood sampling to measure serum NT pro-BNP concentration and have their functional capacity subjectively assessed by their responsible doctors. Participants are followed for 1 year after surgery to assess vital status, postoperative complications and general health utilities. The primary outcome is all-cause death or non-fatal myocardial infarction within 30 days after surgery, and the secondary outcome is all-cause death within 1 year after surgery. Both receiver-operating-characteristic curve methods and risk reclassification table methods will be used to compare the prognostic accuracy of preoperative subjective assessment, peak oxygen consumption during cardiopulmonary exercise testing, Duke Activity Status Index scores and serum NT pro-BNP concentration. The METS Study has received research ethics board approval at all sites. Participant recruitment began in March 2013, and 1-year follow-up is expected to finish in 2016. Publication of the results of the METS Study is anticipated to occur in 2017. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Effect of Baseline Exercise Capacity on Outcomes in Patients With Stable Coronary Heart Disease (A Post Hoc Analysis of the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation Trial)

PubMed Central

Padala, Santosh K.; Sidhu, Mandeep S.; Hartigan, Pamela M.; Maron, David J.; Teo, Koon K.; Spertus, John A.; John Mancini, G.B.; Sedlis, Steven P.; Chaitman, Bernard R.; Heller, Gary V.; Weintraub, William S.; Boden, William E.

2017-01-01

The impact of baseline exercise capacity on clinical outcomes in patients with stable ischemic heart disease randomized to an initial strategy of optimal medical therapy (OMT) with or without percutaneous coronary intervention (PCI) in the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial has not been studied. A post hoc analysis was performed in 1,052 patients of COURAGE (PCI + OMT: n = 527, OMT: n = 525) who underwent exercise treadmill testing at baseline. Patients were categorized into 2 exercise capacity groups based on metabolic equivalents (METs) achieved during baseline exercise treadmill testing (<7 METs: n = 464, ≥7 METs: n = 588) and were followed for a median of 4.6 years. The primary composite end point of death or myocardial infarction was similar in the PCI + OMT group and the OMT group for patients with exercise capacity <7 METs (19.1% vs 16.1%, p = 0.31) and ≥7 METs (13.3% vs 10.3%, p = 0.27). After adjusting for baseline covariates, the hazard ratio (99% confidence interval) for the primary end point for the PCI + OMT group versus the OMT group was 1.42 (0.90 to 2.23, p = 0.05) and for the exercise capacity subgroups of ≥7 METs and <7 METs was 0.75 (0.46 to 1.22, p = 0.13). There was no statistically significant interaction between the original treatment arm allocation (PCI + OMT vs OMT) and baseline exercise capacity. In conclusion, there was no difference in the long-term clinical outcomes in patients with exercise capacity <7 METs compared with ≥7 METs, irrespective of whether they were assigned to initial PCI. Patients with exercise capacity <7 METs did not derive a proportionately greater clinical benefit from PCI + OMT compared with those patients who received OMT alone. Published by Elsevier Inc. (Am J Cardiol 2015;116:1509–1515) PMID:26410604

Supine Lower Body Negative Pressure Exercise Maintains Upright Exercise Capacity in Male Twins during 30 Days of Bed Rest

NASA Technical Reports Server (NTRS)

Lee, Stuart M. C.; Schneider, Suzanne M.; Boda, Wanda L.; Watenpaugh, Donald E.; Macias, Brandon R.; Meyer, R. Scott; Hargens, Alan R.

2006-01-01

Exercise capacity is reduced following both short and long duration exposures to microgravity. We have shown previously that supine lower body negative pressure with exercise (LBNP(sub ex) maintains upright exercise capacity in men after 5d and 15d bed rest, as a simulation of microgravity. We hypothesized that LBNP(sub ex) would protect upright exercise capacity (VO2pk) and sprint performance in eight sets of identical male twins during a 30-d bed rest. Twins within each set were randomly assigned to either a control group (CON) who performed no exercise or to an exercise group (EX) who performed a 40-min interval (40-80% pre-BR VO2pk) LBNP(sub ex) (55+/-4 mmHg) exercise protocol, plus 5 min of resting LBNP, 6 d/wk. LBNP produced footward force equivalent to 1.0- 1.2 times body weight. Pre- and post-bed rest, subjects completed an upright graded exercise test to volitional fatigue and sprint test of 30.5 m. After bed rest, VO2pk was maintained in the EX subjects (-3+/-3%), but was significantly decreased in the CON subjects (-24+/-4%). Sprint time also was increased in the CON subjects (24+/-8%), but maintained in the EX group (8+/-2%). The performance of a supine, interval exercise protocol with LBNP maintains upright exercise capacity and sprint performance during 30 d of bed rest. This exercise countermeasure protocol may help prevent microgravity-induced deconditioning during long duration space flight.

Air Current Applied to the Face Improves Exercise Performance in Patients with COPD.

PubMed

Marchetti, Nathaniel; Lammi, Matthew R; Travaline, John M; Ciccolella, David; Civic, Brian; Criner, Gerard J

2015-10-01

Improving dyspnea and exercise performance are goals of COPD therapy. We tested the hypothesis that air current applied to the face would lessen dyspnea and improve exercise performance in moderate-severe COPD patients. We recruited 10 COPD patients (5 men, age 62 ± 6 years, FEV1 0.93 ± 0.11 L (34 ± 3% predicted), TLC 107 ± 6%, RV 172 ± 18%) naïve to the study hypothesis. Each patient was randomized in a crossover fashion to lower extremity ergometry at constant submaximal workload with a 12-diameter fan directed at the patients face or exposed leg. Each patients' studies were separated by at least 1 week. Inspiratory capacity and Borg dyspnea score were measured every 2 min and at maximal exercise. Total exercise time was longer when the fan was directed to the face (14.3 ± 12 vs. 9.4 ± 7.6 min, face vs. leg, respectively, p = 0.03). Inspiratory capacity tended to be greater with the fan directed to the face (1.4 (0.6-3.25) vs. 1.26 (0.56-2.89) L, p = 0.06). There was a reduction in dynamic hyperinflation, as reflected by higher IRV area in the fan on face group (553 ± 562 a.u. vs. 328 ± 319 a.u., p = 0.047). There was a significant improvement in the Borg dyspnea score at maximal exercise (5.0 (0-10) vs. 6.5 (0-10), p = 0.03), despite exercising for 34 % longer with the fan directed to the face. Air current applied to the face improves exercise performance in COPD. Possible mechanisms include an alteration in breathing pattern that diminishes development of dynamic hyperinflation or to a change in perception of breathlessness.

[Sports medical aspects in cardiac risk stratification--heart rate variability and exercise capacity].

PubMed

Banzer, W; Lucki, K; Bürklein, M; Rosenhagen, A; Vogt, L

2006-12-01

The present study investigates the association of the predicted CHD-risk (PROCAM) with the individual endurance capacity and heart rate variability (HRV) in a population-based sample of sedentary elderly. After stratification, in 57 men (48.1+/-9.5 yrs.) with an overall PROCAM-risk <10% (28.7+/-10.9 points) and 22 men (54.5+/-7.7 yrs.) with a coronary 10-year risk > or =10% (50.8+/-5.6 points) cycle ergometries and short-term HRV analysis of time (RRMEAN, SDNN, RMSSD) and frequency domain parameters (LF, HF, TP, LF/HF) were conducted. Additionally the autonomic stress index (SI) was calculated. Nonparametric tests were used for statistical correlation analysis (Spearman rho) and group comparisons (Mann-Whitney). For endurance capacity [W/kg] (r=-0.469, p<0.001), SDNN (r=-0.302, p<0.05), RMSSD (r= -0.311, p<0.05), LF (r=-0.325, p<0.05), HF (r= -0.311, p<0.05) and TP (r= -0.307, p<0.05) negative monotone correlations with the coronary score-risk were determined. Significant positive correlations were calculated for SI (r=0.476, p<0.001). Except for RRMEAN and LF/HF significant group differences (p<0.05) were computed for SDNN (30.0+/-20.0 vs 20.0+/-10.0 ms), RMSSD (22.2+/-18.3 vs 18.0+/-8.7 ms), LF (90.9+/-241.5 vs 41.35+/-81.1 ms(2)), HF (43.0+/-105.1 vs 18.0+/-27.0 ms(2)) and TP (189.0+/-457.1 vs 100.0+/-157.6 ms(2)). Significant differences (p<0.01) were evaluated for exercise capacity (2.4+/-0.5 vs 1.8+/-0.3 W/kg) and SI (90+/-183 vs 322+/-291). The results underline the predictive value of HRV analysis in risk stratification and outline the interrelation of a decreased exercise capacity and autonomic function with a raised individual 10-year cardiac risk. As an independent parameter of the vegetative regulatory state the stress index may contribute to an increased practical relevance of short-time HRV analysis.

One year of high-intensity interval training improves exercise capacity, but not left ventricular function in stable heart transplant recipients: a randomised controlled trial.

PubMed

Rustad, Lene A; Nytrøen, Kari; Amundsen, Brage H; Gullestad, Lars; Aakhus, Svend

2014-02-01

Heart transplant recipients have lower exercise capacity and impaired cardiac function compared with the normal population. High-intensity interval training (HIIT) improves exercise capacity and cardiac function in patients with heart failure and hypertension, but the effect on cardiac function in stable heart transplant recipients is not known. Thus, we investigated whether HIIT improved cardiac function and exercise capacity in stable heart transplant recipients by use of comprehensive rest- and exercise-echocardiography and cardiopulmonary exercise testing. Fifty-two clinically stable heart transplant recipients were randomised either to HIIT (4 × 4 minutes at 85-95% of peak heart rate three times per week for eight weeks) or to control. Three such eight-week periods were distributed throughout one year. Echocardiography (rest and submaximal exercise) and cardiopulmonary exercise testing were performed at baseline and follow-up. One year of HIIT increased VO 2peak from 27.7 ± 5.5 at baseline to 30.9 ± 5.0 ml/kg/min at follow-up, while the control group remained unchanged (28.5 ± 7.0 vs. 28.0 ± 6.7 ml/kg per min, p < 0.001 for difference between the groups). Systolic and diastolic left ventricular functions at rest and during exercise were generally unchanged by HIIT. Whereas HIIT is feasible in heart transplant recipients and effectively improves exercise capacity, it does not alter cardiac systolic and diastolic function significantly. Thus, the observed augmentation in exercise capacity is best explained by extra-cardiac adaptive mechanisms.

Effects of 1-Methylnicotinamide (MNA) on Exercise Capacity and Endothelial Response in Diabetic Mice.

PubMed

Przyborowski, Kamil; Wojewoda, Marta; Sitek, Barbara; Zakrzewska, Agnieszka; Kij, Agnieszka; Wandzel, Krystyna; Zoladz, Jerzy Andrzej; Chlopicki, Stefan

2015-01-01

1-Methylnicotinamide (MNA), which was initially considered to be a biologically inactive endogenous metabolite of nicotinamide, has emerged as an anti-thrombotic and anti-inflammatory agent with the capacity to release prostacyclin (PGI2). In the present study, we characterized the effects of MNA on exercise capacity and the endothelial response to exercise in diabetic mice. Eight-week-old db/db mice were untreated or treated with MNA for 4 weeks (100 mg·kg-1), and their exercise capacity as well as NO- and PGI2-dependent response to endurance running were subsequently assessed. MNA treatment of db/db mice resulted in four-fold and three-fold elevation of urine concentrations of MNA and its metabolites (Met-2PY + Met-4PY), respectively (P<0.01), but did not affect HbA1c concentration, fasting glucose concentration or lipid profile. However, insulin sensitivity was improved (P<0.01). In MNA-treated db/db mice, the time to fatigue for endurance exercise was significantly prolonged (P<0.05). Post-exercise Δ6-keto-PGF1α (difference between mean concentration in the sedentary and exercised groups) tended to increase, and post-exercise leukocytosis was substantially reduced in MNA-treated animals. In turn, the post-exercise fall in plasma concentration of nitrate was not affected by MNA. In conclusion, we demonstrated for the first time that MNA improves endurance exercise capacity in mice with diabetes, and may also decrease the cardiovascular risk of exercise.

Impaired left ventricular systolic function reserve limits cardiac output and exercise capacity in HFpEF patients due to systemic hypertension.

PubMed

Henein, Michael; Mörner, Stellan; Lindmark, Krister; Lindqvist, Per

2013-09-30

Heart failure (HF) patients with preserved left ventricular (LV) ejection fraction (EF) (HFpEF) due to systemic hypertension (SHT) are known to have limited exercise tolerance. Despite having normal EF at rest, we hypothesize that these patients have abnormal systolic function reserve limiting their exercise capacity. Seventeen patients with SHT (mean age 68 ± 9 years) but no valve disease and 14 healthy individuals (mean age of 65 ± 10 years) underwent resting and peak exercise echocardiography using conventional, tissue Doppler and speckle tracking techniques. The differences between resting and peak exercise values were also analyzed (Δ). Exercise capacity was determined as the workload divided by body surface area. Resting values for left atrial (LA) volume/BSA (r=-0.66, p<0.001) and global longitudinal strain rate (GLSR) in early (e) and late (a) diastole (r=0.47 and 0.46, p<0.05 for both) correlated with exercise capacity. LVEF increased during exercise in normals (mean Δ EF=10 ± 8%) but failed to do so in patients (mean Δ EF=0.6 ± 9%, p<0.001 between groups). LV GLSR during systole (s) also failed to increase with exercise in patients, to the same extent as it did in normals (0.2 ± 0.2 vs. 0.6 ± 0.3 1/s, p<0.001). The difference between rest and exercise (Δ) in LV lateral wall systolic velocity from tissue Doppler (s') (0.71, p<0.001), Δ in cardiac output (r=0.60, p<0.001) and Δ GLSRs (r=0.48, p<0.05) all correlated with exercise capacity independent of changes in heart rate. HFpEF patients with hypertensive LV disease have significantly limited exercise capacity which is related to left atrial enlargement as well as compromised LV systolic function at the time of the symptoms. The limited myocardial systolic function reserve seems to be underlying important explanation for their limited exercise capacity. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Maximal exercise capacity in patients with obstructive sleep apnoea syndrome: A systematic review and meta-analysis.

PubMed

Mendelson, Monique; Marillier, Mathieu; Bailly, Sébastien; Flore, Patrice; Borel, Jean-Christian; Vivodtzev, Isabelle; Doutreleau, Stéphane; Tamisier, Renaud; Pépin, Jean-Louis; Verges, Samuel

2018-04-26

Maximal aerobic capacity is a strong health predictor and peak oxygen consumption (VO 2peak ) is considered a reflection of total body health. No systematic reviews or meta-analysis' to date have synthesised the existing data regarding VO 2peak in patients with obstructive sleep apnoea (OSA).A systematic review of English and French articles using Pubmed/Medline and Embase included studies assessing VO 2peak of OSA patients in mL·kg -1 ·min -1 compared with controls or in % predicted. Two independent reviewers analysed the studies, extracted the data and assessed the quality of evidence.Mean VO 2peak expressed in mL·kg -1 ·min -1 was significantly lower in patients with OSA when compared with controls (mean difference=-2.7 mL·kg -1 ·min -1 ; p<0.001; n=850). This reduction in VO 2peak was found to be larger in non-obese patients (BMI<30 kg·m -2 ). Mean VO 2peak in % predicted was 90.7±21.0% in OSA patients (n=643).OSA patients present reduced maximal aerobic capacity, which can be associated with increased cardiovascular risks and reduced survival in certain patient subgroups. Maximal exercise testing can be useful to characterise functional limitation and to evaluate health status in OSA patients. Registration # CRD42017057319. Copyright ©ERS 2018.

p53 improves aerobic exercise capacity and augments skeletal muscle mitochondrial DNA content.

PubMed

Park, Joon-Young; Wang, Ping-Yuan; Matsumoto, Takumi; Sung, Ho Joong; Ma, Wenzhe; Choi, Jeong W; Anderson, Stasia A; Leary, Scot C; Balaban, Robert S; Kang, Ju-Gyeong; Hwang, Paul M

2009-09-25

Exercise capacity is a physiological characteristic associated with protection from both cardiovascular and all-cause mortality. p53 regulates mitochondrial function and its deletion markedly diminishes exercise capacity, but the underlying genetic mechanism orchestrating this is unclear. Understanding the biology of how p53 improves exercise capacity may provide useful insights for improving both cardiovascular as well as general health. The purpose of this study was to understand the genetic mechanism by which p53 regulates aerobic exercise capacity. Using a variety of physiological, metabolic, and molecular techniques, we further characterized maximum exercise capacity and the effects of training, measured various nonmitochondrial and mitochondrial determinants of exercise capacity, and examined putative regulators of mitochondrial biogenesis. As p53 did not affect baseline cardiac function or inotropic reserve, we focused on the involvement of skeletal muscle and now report a wider role for p53 in modulating skeletal muscle mitochondrial function. p53 interacts with Mitochondrial Transcription Factor A (TFAM), a nuclear-encoded gene important for mitochondrial DNA (mtDNA) transcription and maintenance, and regulates mtDNA content. The increased mtDNA in p53(+/+) compared to p53(-/-) mice was more marked in aerobic versus glycolytic skeletal muscle groups with no significant changes in cardiac tissue. These in vivo observations were further supported by in vitro studies showing overexpression of p53 in mouse myoblasts increases both TFAM and mtDNA levels whereas depletion of TFAM by shRNA decreases mtDNA content. Our current findings indicate that p53 promotes aerobic metabolism and exercise capacity by using different mitochondrial genes and mechanisms in a tissue-specific manner.

An integrated physiology model to study regional lung damage effects and the physiologic response

PubMed Central

2014-01-01

Background This work expands upon a previously developed exercise dynamic physiology model (DPM) with the addition of an anatomic pulmonary system in order to quantify the impact of lung damage on oxygen transport and physical performance decrement. Methods A pulmonary model is derived with an anatomic structure based on morphometric measurements, accounting for heterogeneous ventilation and perfusion observed experimentally. The model is incorporated into an existing exercise physiology model; the combined system is validated using human exercise data. Pulmonary damage from blast, blunt trauma, and chemical injury is quantified in the model based on lung fluid infiltration (edema) which reduces oxygen delivery to the blood. The pulmonary damage component is derived and calibrated based on published animal experiments; scaling laws are used to predict the human response to lung injury in terms of physical performance decrement. Results The augmented dynamic physiology model (DPM) accurately predicted the human response to hypoxia, altitude, and exercise observed experimentally. The pulmonary damage parameters (shunt and diffusing capacity reduction) were fit to experimental animal data obtained in blast, blunt trauma, and chemical damage studies which link lung damage to lung weight change; the model is able to predict the reduced oxygen delivery in damage conditions. The model accurately estimates physical performance reduction with pulmonary damage. Conclusions We have developed a physiologically-based mathematical model to predict performance decrement endpoints in the presence of thoracic damage; simulations can be extended to estimate human performance and escape in extreme situations. PMID:25044032

Left ventricular chamber stiffness at rest as a determinant of exercise capacity in heart failure subjects with decreased ejection fraction.

PubMed

Meyer, Timothy E; Karamanoglu, Mustafa; Ehsani, Ali A; Kovács, Sándor J

2004-11-01

Impaired exercise tolerance, determined by peak oxygen consumption (VO2 peak), is predictive of mortality and the necessity for cardiac transplantation in patients with chronic heart failure (HF). However, the role of left ventricular (LV) diastolic function at rest, reflected by chamber stiffness assessed echocardiographically, as a determinant of exercise tolerance is unknown. Increased LV chamber stiffness and limitation of VO2 peak are known correlates of HF. Yet, the relationship between chamber stiffness and VO2 peak in subjects with HF has not been fully determined. Forty-one patients with HF New York Heart Association [(NYHA) class 2.4 +/- 0.8, mean +/- SD] had echocardiographic studies and VO2 peak measurements. Transmitral Doppler E waves were analyzed using a previously validated method to determine k, the LV chamber stiffness parameter. Multiple linear regression analysis of VO(2 peak) variance indicated that LV chamber stiffness k (r2 = 0.55) and NYHA classification (r2 = 0.43) were its best independent predictors and when taken together account for 59% of the variability in VO2 peak. We conclude that diastolic function at rest, as manifested by chamber stiffness, is a major determinant of maximal exercise capacity in HF.

[Effects of TES program on exercise capacity, self-efficacy and patient compliance in patients with myocardial infarction].

PubMed

Choo, Jina; Kim, Ja-Mae; Hong, Kyung-Pyo

2003-12-01

This study aimed to develop a TES program to improve exercise capacity to promote patient compliance to the prescribed exercise, and to test the feasibility of the program. The 8-week TES program consisted of three components : exercise training, self-efficacy enhancement and social support. Using the matching of gender, age, and the left ventricular ejection fraction, thirty one subjects were consecutively assigned to either TES group (n=15, 52+7 years) or Control group (n=16, 58+11 years) 3 weeks after MI. With the exception of exercise compliance (only after the TES program), the exercise capacity and exercise self-efficacy were both measured both before and after the 8-week TES program. The VO2peak (p=.043), anaerobic threshold (p=.023) and exercise duration (p=.015) improved in TES group compared to Control group after 8 weeks. The cardiac exercise self-efficacy (p=.036) was significantly higher in TES group than Control group. There was a significant increase of exercise compliance(p=.005) in TES group compared to Control group. The 8-week TES program improved the exercise capacity, exercise self-efficacy and exercise compliance. A appropriately implemented TES program in cardiovascular nursing practice may promote healthy behavioral modification and, therefore, contributing to reduce the risk of mortality and morbidity in MI patients.

Effects of lumbopelvic sling and abdominal drawing-in exercises on lung capacity in healthy adults.

PubMed

Kim, Myoung-Kwon; Cha, Hyun-Gyu; Shin, Young-Jun

2016-08-01

[Purpose] To examine the effects of lumbopelvic sling and abdominal drawing-in exercises on the lung capacities of healthy subjects. [Subjects and Methods] Twenty-nine healthy subjects with no orthopedic history of the back were recruited. Subjects were randomly assigned to a experimental group and control group. Subjects were allocated to one of two groups; an experimental group that underwent lumbopelvic sling and abdominal drawing-in exercises and a control group that underwent treadmill and abdominal drawing-in exercises. Lung capacities were evaluated 4 weeks after exercises. [Results] The experimental group showed significant increments in EV, ERV, IRV, VT vs. pre-intervention results, and the control group showed significant increments in the EVC and IRV. Significant intergroup differences were observed in terms of post-training gains in EVC, IRV, and VT. [Conclusion] Combined application of lumbopelvic sling and abdominal drawing-in exercises were found to have a positive effect on lung capacity.

New insights into the benefits of exercise for muscle health in patients with idiopathic inflammatory myositis.

PubMed

Alemo Munters, Li; Alexanderson, Helene; Crofford, Leslie J; Lundberg, Ingrid E

2014-07-01

With recommended treatment, a majority with idiopathic inflammatory myopathy (IIM) develop muscle impairment and poor health. Beneficial effects of exercise have been reported on muscle performance, aerobic capacity and health in chronic polymyositis and dermatomyositis and to some extent in active disease and inclusion body myositis (IBM). Importantly, randomized controlled trials (RCTs) indicate that improved health and decreased clinical disease activity could be mediated through increased aerobic capacity. Recently, reports seeking mechanisms underlying effects of exercise in skeletal muscle indicate increased aerobic capacity (i.e. increased mitochondrial capacity and capillary density, reduced lactate levels), activation of genes in aerobic phenotype and muscle growth programs, and down regulation in genes related to inflammation. Altogether, exercise contributes to both systemic and within-muscle adaptations demonstrating that exercise is fundamental to improve muscle performance and health in IIM. There is a need for RCTs to study effects of exercise in active disease and IBM.

A shirt containing multistage phase change material and active cooling components was associated with increased exercise capacity in a hot, humid environment.

PubMed

McFarlin, Brian K; Henning, Andrea L; Venable, Adam S; Williams, Randall R; Best Sampson, Jill N

2016-08-01

Recent advances in clothing design include the incorporation of phase change materials (PCM) and other active cooling components (ACC) to provide better body heat dissipation. The purpose of this study was to determine the effect of wearing a shirt containing multistage PCM/ACC on exercise capacity at low (5.0), moderate-high (7.5) and extreme (9.0) levels of the physiological strain index (PSI). Fourteen individuals tested two shirts (control vs. cooling) during 45-min of interval running in a hot, humid (35 ± 1 °C; 55 ± 6% RH) environment. The cooling shirt resulted in an 8% improvement in exercise capacity at a PSI of 7.5 (p < 0.05). The observed increase in exercise capacity would likely translate to a significant improvement in exercise performance. More research is needed to determine a best practice approach for the use of cooling clothing as a counter to exercise-induced heat exposure. Practitioner Summary: In this report, we demonstrate that when forced to exercise in a hot, humid environment, an individual's exercise capacity may increase by as much as 8% when wearing a shirt composed of multistage phase change material and active cooling components.

Reduced Exercise Tolerance and Pulmonary Capillary Recruitment with Remote Secondhand Smoke Exposure

PubMed Central

Arjomandi, Mehrdad; Haight, Thaddeus; Sadeghi, Nasrat; Redberg, Rita; Gold, Warren M.

2012-01-01

Rationale Flight attendants who worked on commercial aircraft before the smoking ban in flights (pre-ban FAs) were exposed to high levels of secondhand smoke (SHS). We previously showed never-smoking pre-ban FAs to have reduced diffusing capacity (Dco) at rest. Methods To determine whether pre-ban FAs increase their Dco and pulmonary blood flow () during exercise, we administered a symptom-limited supine-posture progressively increasing cycle exercise test to determine the maximum work (watts) and oxygen uptake () achieved by FAs. After 30 min rest, we then measured Dco and at 20, 40, 60, and 80 percent of maximum observed work. Results The FAs with abnormal resting Dco achieved a lower level of maximum predicted work and compared to those with normal resting Dco (mean±SEM; 88.7±2.9 vs. 102.5±3.1%predicted ; p = 0.001). Exercise limitation was associated with the FAs' FEV1 (r = 0.33; p = 0.003). The Dco increased less with exercise in those with abnormal resting Dco (mean±SEM: 1.36±0.16 vs. 1.90±0.16 ml/min/mmHg per 20% increase in predicted watts; p = 0.020), and amongst all FAs, the increase with exercise seemed to be incrementally lower in those with lower resting Dco. Exercise-induced increase in was not different in the two groups. However, the FAs with abnormal resting Dco had less augmentation of their Dco with increase in during exercise (mean±SEM: 0.93±0.06 vs. 1.47±0.09 ml/min/mmHg per L/min; p<0.0001). The Dco during exercise was inversely associated with years of exposure to SHS in those FAs with ≥10 years of pre-ban experience (r = −0.32; p = 0.032). Conclusions This cohort of never-smoking FAs with SHS exposure showed exercise limitation based on their resting Dco. Those with lower resting Dco had reduced pulmonary capillary recruitment. Exposure to SHS in the aircraft cabin seemed to be a predictor for lower Dco during exercise. PMID:22493689

Cardiovascular rehabilitation soon after stroke using feedback-controlled robotics-assisted treadmill exercise: study protocol of a randomised controlled pilot trial.

PubMed

Stoller, Oliver; de Bruin, Eling D; Schuster-Amft, Corina; Schindelholz, Matthias; de Bie, Rob A; Hunt, Kenneth J

2013-09-22

After experiencing a stroke, most individuals also suffer from cardiac disease, are immobile and thus have low endurance for exercise. Aerobic capacity is seriously reduced in these individuals and does not reach reasonable levels after conventional rehabilitation programmes. Cardiovascular exercise is beneficial for improvement of aerobic capacity in mild to moderate stroke. However, less is known about its impact on aerobic capacity, motor recovery, and quality-of-life in severely impaired individuals. The aim of this pilot study is to explore the clinical efficacy and feasibility of cardiovascular exercise with regard to aerobic capacity, motor recovery, and quality-of-life using feedback-controlled robotics-assisted treadmill exercise in non-ambulatory individuals soon after experiencing a stroke. This will be a single-centred single blind, randomised control trial with a pre-post intervention design. Subjects will be recruited early after their first stroke (≤20 weeks) at a neurological rehabilitation clinic and will be randomly allocated to an inpatient cardiovascular exercise programme that uses feedback-controlled robotics-assisted treadmill exercise (experimental) or to conventional robotics-assisted treadmill exercise (control). Intervention duration depends on the duration of each subject's inpatient rehabilitation period. Aerobic capacity, as the primary outcome measure, will be assessed using feedback-controlled robotics-assisted treadmill-based cardiopulmonary exercise testing. Secondary outcome measures will include gait speed, walking endurance, standing function, and quality-of-life. Outcome assessment will be conducted at baseline, after each 4-week intervention period, and before clinical discharge. Ethical approval has been obtained. Whether cardiovascular exercise in non-ambulatory individuals early after stroke has an impact on aerobic capacity, motor recovery, and quality-of-life is not yet known. Feedback-controlled robotics-assisted treadmill exercise is a relatively recent intervention method and might be used to train and evaluate aerobic capacity in this population. The present pilot trial is expected to provide new insights into the implementation of early cardiovascular exercise for individuals with severe motor impairment. The findings of this study may guide future research to explore the effects of early cardiovascular activation after severe neurological events. This trial is registered with the Clinical Trials.gov Registry (NCT01679600).

Computational Modeling of Pathophysiologic Responses to Exercise in Fontan Patients

PubMed Central

Kung, Ethan; Perry, James C.; Davis, Christopher; Migliavacca, Francesco; Pennati, Giancarlo; Giardini, Alessandro; Hsia, Tain-Yen; Marsden, Alison

2014-01-01

Reduced exercise capacity is nearly universal among Fontan patients. Although many factors have emerged as possible contributors, the degree to which each impacts the overall hemodynamics is largely unknown. Computational modeling provides a means to test hypotheses of causes of exercise intolerance via precisely controlled virtual experiments and measurements. We quantified the physiological impacts of commonly encountered, clinically relevant dysfunctions introduced to the exercising Fontan system via a previously developed lumped-parameter model of Fontan exercise. Elevated pulmonary arterial pressure was observed in all cases of dysfunction, correlated with lowered cardiac output, and often mediated by elevated atrial pressure. Pulmonary vascular resistance was not the most significant factor affecting exercise performance as measured by cardiac output. In the absence of other dysfunctions, atrioventricular valve insufficiency alone had significant physiological impact, especially under exercise demands. The impact of isolated dysfunctions can be linearly summed to approximate the combined impact of several dysfunctions occurring in the same system. A single dominant cause of exercise intolerance was not identified, though several hypothesized dysfunctions each led to variable decreases in performance. Computational predictions of performance improvement associated with various interventions should be weighed against procedural risks and potential complications, contributing to improvements in routine patient management protocol. PMID:25260878

Exercise training programs to improve hand rim wheelchair propulsion capacity: a systematic review.

PubMed

Zwinkels, Maremka; Verschuren, Olaf; Janssen, Thomas Wj; Ketelaar, Marjolijn; Takken, Tim

2014-09-01

An adequate wheelchair propulsion capacity is required to perform daily life activities. Exercise training may be effective to gain or improve wheelchair propulsion capacity. This review investigates whether different types of exercise training programs are effective in improving wheelchair propulsion capacity. PubMed and EMBASE databases were searched from their respective inceptions in October 2013. Exercise training studies with at least one outcome measure regarding wheelchair propulsion capacity were included. In this study wheelchair propulsion capacity includes four parameters to reflect functional wheelchair propulsion: cardio-respiratory fitness (aerobic capacity), anaerobic capacity, muscular fitness and mechanical efficiency. Articles were not selected on diagnosis, training type or mode. Studies were divided into four training types: interval, endurance, strength, and mixed training. Methodological quality was rated with the PEDro scale, and the level of evidence was determined. The 21 included studies represented 249 individuals with spinal-cord injury (50%), various diagnoses like spina bifida (4%), cerebral palsy (2%), traumatic injury, (3%) and able-bodied participants (38%). All interval training studies found a significant improvement of 18-64% in wheelchair propulsion capacity. Three out of five endurance training studies reported significant effectiveness. Methodological quality was generally poor and there were only two randomised controlled trials. Exercise training programs seem to be effective in improving wheelchair propulsion capacity. However, there is remarkably little research, particularly for individuals who do not have spinal-cord injury. © The Author(s) 2014.

Utilization of the graded universal testing system to increase the efficiency for assessing aerobic and anaerobic capacity

NASA Technical Reports Server (NTRS)

Rodgers, Sandra L.

1992-01-01

The in-flight exercise test performed by cosmonauts as part of the Russian Exercise Countermeasure Program is limited to 5 minutes due to communication restrictions. During a recent graded exercise test on a U.S. Shuttle flight, the test was terminated early due to an upcoming loss of signal (LOS) with the ground. This exercise test was a traditional test where the subject's exercise capacity dictates the length of the test. For example, one crew member may take 15 minutes to complete the test, while another may take 18 minutes. The traditional exercise test limits the flight schedulers to large blocks of space flight time in order to provide medical and research personnel information on the fitness capacity (maximal oxygen uptake: VO2max) of crew members during flight. A graded exercise test that would take a finite amount of time and a set preparation and recovery time would ease this problem by allowing flight schedulers to plan exercise tests in advance of LOS. The Graded Universal Testing System (GUTS) was designed to meet this goal. Fitness testing of astronauts before and after flight provides pertinent data on many variables. The Detailed Supplemental Objective (DSO608) protocol (6) is one of the graded exercise tests (GXT) currently used in astronaut testing before and after flight. Test times for this protocol have lasted from 11 to 18 minutes. Anaerobic capacity is an important variable that is currently not being evaluated before and after flight. Recent reports (1,2,5) from the literature have suggested that the oxygen deficit at supramaximal exercise is a measure of anaerobic capacity. We postulated that the oxygen deficit at maximal exercise would be an indication of anaerobic capacity. If this postulate can be accepted, then the efficiency of acquiring data from a graded exercise test would increase at least twofold. To examine this hypothesis anaerobic capacity was measured using a modified treadmill test (3,4) designed to exhaust the anaerobic systems in approximately 45 to 75 seconds. Lactate concentration in the blood was analyzed after all tests, since lactate is the end-product of anaerobic energy production. Therefore, the peak lactate response is an additional indication of anaerobic capacity. A preliminary comparison of the GUTS and the DSO608 suggests that the GUTS protocol would increase the efficiency of VO2max testing of astronauts before and after flight. Results for anaerobic capacity have not been tabulated.

A practical guide to exercise training for heart failure patients.

PubMed

Smart, Neil; Fang, Zhi You; Marwick, Thomas H

2003-02-01

Exercise training has been shown to improve exercise capacity in patients with heart failure. We sought to examine the optimal strategy of exercise training for patients with heart failure. Review of the published data on the characteristics of the training program, with comparison of physiologic markers of exercise capacity in heart failure patients and healthy individuals and comparison of the change in these characteristics after an exercise training program. Many factors, including the duration, supervision, and venue of exercise training; the volume of working muscle; the delivery mode (eg, continuous vs. intermittent exercise), training intensity; and the concurrent effects of medical treatments may influence the results of exercise training in heart failure. Starting in an individually prescribed and safely monitored hospital-based program, followed by progression to an ongoing and progressive home program of exercise appears to be the best solution to the barriers of anxiety, adherence, and "ease of access" encountered by the heart failure patient. Various exercise training programs have been shown to improve exercise capacity and symptom status in heart failure, but these improvements may only be preserved with an ongoing maintenance program.

Aerobic training in adults after atrial switch procedure for transposition of the great arteries improves exercise capacity without impairing systemic right ventricular function.

PubMed

Westhoff-Bleck, Mechthild; Schieffer, Bernhard; Tegtbur, Uwe; Meyer, Gerd Peter; Hoy, Ludwig; Schaefer, Arnd; Tallone, Ezequiel Marcello; Tutarel, Oktay; Mertins, Ramona; Wilmink, Lena Mara; Anker, Stefan D; Bauersachs, Johann; Roentgen, Philipp

2013-12-05

Exercise training safely and efficiently improves symptoms in patients with heart failure due to left ventricular dysfunction. However, studies in congenital heart disease with systemic right ventricle are scarce and results are controversial. In a randomised controlled study we investigated the effect of aerobic exercise training on exercise capacity and systemic right ventricular function in adults with d-transposition of the great arteries after atrial redirection surgery (28.2 ± 3.0 years after Mustard procedure). 48 patients (31 male, age 29.3 ± 3.4 years) were randomly allocated to 24 weeks of structured exercise training or usual care. Primary endpoint was the change in maximum oxygen uptake (peak VO2). Secondary endpoints were systemic right ventricular diameters determined by cardiac magnetic resonance imaging (CMR). Data were analysed per intention to treat analysis. At baseline peak VO2 was 25.5 ± 4.7 ml/kg/min in control and 24.0 ± 5 ml/kg/min in the training group (p=0.3). Training significantly improved exercise capacity (treatment effect for peak VO2 3.8 ml/kg/min, 95% CI: 1.8 to 5.7; p=0.001), work load (p=0.002), maximum exercise time (p=0.002), and NYHA class (p=0.046). Systemic ventricular function and volumes determined by CMR remained unchanged. None of the patients developed signs of cardiac decompensation or arrhythmias while on exercise training. Aerobic exercise training did not detrimentally affect systemic right ventricular function, but significantly improved exercise capacity and heart failure symptoms. Aerobic exercise training can be recommended for patients following atrial redirection surgery to improve exercise capacity and to lessen or prevent heart failure symptoms. ( ClinicalTrials.gov #NCT00837603). © 2013.

Use of ratings of perceived exertion in sports.

PubMed

Eston, Roger

2012-06-01

The rating of perceived exertion (RPE) is a recognized marker of intensity and of homeostatic disturbance during exercise. It is typically monitored during exercise tests to complement other measures of intensity. The purpose of this commentary is to highlight the remarkable value of RPE as a psychophysiological integrator in adults. It can be used in such diverse fashions as to predict exercise capacity, assess changes in training status, and explain changes in pace and pacing strategy. In addition to using RPE to self-regulate exercise, a novel application of the intensity:RPE relationship is to clamp RPE at various levels to produce self-paced bouts of exercise, which can be used to assess maximal functional capacity. Research also shows that the rate of increase in RPE during self-paced competitive events of varying distance, or constant-load tasks where the participant exercises until volitional exhaustion, is proportional to the duration that remains. These findings suggest that the brain regulates RPE and performance in an anticipatory manner based on awareness of metabolic reserves at the start of an event and certainty of the anticipated end point. Changes in pace may be explained by a continuous internal negotiation of momentary RPE compared with a preplanned "ideal rate of RPE progression" template, which takes into account the portion of distance covered and the anticipated end point. These observations have led to the development of new techniques to analyze the complex relationship of RPE and pacing. The use of techniques to assess frontal-cortex activity will lead to further advances in understanding.

With age a lower individual breathing reserve is associated with a higher maximal heart rate.

PubMed

Burtscher, Martin; Gatterer, Hannes; Faulhaber, Martin; Burtscher, Johannes

2018-01-01

Maximal heart rate (HRmax) is linearly declining with increasing age. Regular exercise training is supposed to partly prevent this decline, whereas sex and habitual physical activity do not. High exercise capacity is associated with a high cardiac output (HR x stroke volume) and high ventilatory requirements. Due to the close cardiorespiratory coupling, we hypothesized that the individual ventilatory response to maximal exercise might be associated with the age-related HRmax. Retrospective analyses have been conducted on the results of 129 consecutively performed routine cardiopulmonary exercise tests. The study sample comprised healthy subjects of both sexes of a broad range of age (20-86 years). Maximal values of power output, minute ventilation, oxygen uptake and heart rate were assessed by the use of incremental cycle spiroergometry. Linear multivariate regression analysis revealed that in addition to age the individual breathing reserve at maximal exercise was independently predictive for HRmax. A lower breathing reserve due to a high ventilatory demand and/or a low ventilatory capacity, which is more pronounced at a higher age, was associated with higher HRmax. Age explained the observed variance in HRmax by 72% and was improved to 83% when the variable "breathing reserve" was entered. The presented findings indicate an independent association between the breathing reserve at maximal exercise and maximal heart rate, i.e. a low individual breathing reserve is associated with a higher age-related HRmax. A deeper understanding of this association has to be investigated in a more physiological scenario. Copyright © 2017 Elsevier B.V. All rights reserved.

Nonparetic Knee Extensor Strength Is the Determinant of Exercise Capacity of Community-Dwelling Stroke Survivors

PubMed Central

Wang, Wei-Te; Huang, Ling-Tzu; Chou, Ya-Hui; Wei, Ta-Sen; Lin, Chung-Che

2014-01-01

Objective. To investigate the relationship among walking speed, exercise capacity, and leg strength in community dwelling stroke subjects and to evaluate which one was the leading determinant factor of them. Design. This is a descriptive, cross-sectional study. Thirty-five chronic stroke patients who were able to walk independently in their community were enrolled. Walking speed was evaluated by using the 12-meter walking test. A maximal exercise test was used to determine the stroke subjects' exercise capacity. Knee extensor strength, measured as isokinetic torque, was assessed by isokinetic dynamometer. Results. The main walking speed of our subjects was 0.52 m/s. Peak oxygen uptake (VO2 peak) was 1.21 ± 0.43 L/min. Knee extensor strength, no matter whether paretic or nonparetic side, was significantly correlated to 12-meter walking speed and exercise capacity. Linear regression also showed the strength of the affected knee extensor was the determinant of walking speed and that of the nonparetic knee extensor was the determinant of exercise capacity in community dwelling stroke subjects. Conclusions. Walking speed and peak oxygen uptake were markedly decreased after stroke. Knee extensor strength of nonparetic leg was the most important determinant of exercise capacity of the community-dwelling stroke subjects. Knee extensor strengthening should be emphasized to help stroke patient to achieve optimal community living. PMID:25197712

Nonparetic knee extensor strength is the determinant of exercise capacity of community-dwelling stroke survivors.

PubMed

Wang, Wei-Te; Huang, Ling-Tzu; Chou, Ya-Hui; Wei, Ta-Sen; Lin, Chung-Che

2014-01-01

To investigate the relationship among walking speed, exercise capacity, and leg strength in community dwelling stroke subjects and to evaluate which one was the leading determinant factor of them. This is a descriptive, cross-sectional study. Thirty-five chronic stroke patients who were able to walk independently in their community were enrolled. Walking speed was evaluated by using the 12-meter walking test. A maximal exercise test was used to determine the stroke subjects' exercise capacity. Knee extensor strength, measured as isokinetic torque, was assessed by isokinetic dynamometer. The main walking speed of our subjects was 0.52 m/s. Peak oxygen uptake (VO₂ peak) was 1.21 ± 0.43 L/min. Knee extensor strength, no matter whether paretic or nonparetic side, was significantly correlated to 12-meter walking speed and exercise capacity. Linear regression also showed the strength of the affected knee extensor was the determinant of walking speed and that of the nonparetic knee extensor was the determinant of exercise capacity in community dwelling stroke subjects. Walking speed and peak oxygen uptake were markedly decreased after stroke. Knee extensor strength of nonparetic leg was the most important determinant of exercise capacity of the community-dwelling stroke subjects. Knee extensor strengthening should be emphasized to help stroke patient to achieve optimal community living.

Comparison of three methods to identify the anaerobic threshold during maximal exercise testing in patients with chronic heart failure.

PubMed

Beckers, Paul J; Possemiers, Nadine M; Van Craenenbroeck, Emeline M; Van Berendoncks, An M; Wuyts, Kurt; Vrints, Christiaan J; Conraads, Viviane M

2012-02-01

Exercise training efficiently improves peak oxygen uptake (V˙O2peak) in patients with chronic heart failure. To optimize training-derived benefit, higher exercise intensities are being explored. The correct identification of anaerobic threshold is important to allow safe and effective exercise prescription. During 48 cardiopulmonary exercise tests obtained in patients with chronic heart failure (59.6 ± 11 yrs; left ventricular ejection fraction, 27.9% ± 9%), ventilatory gas analysis findings and lactate measurements were collected. Three technicians independently determined the respiratory compensation point (RCP), the heart rate turning point (HRTP) and the second lactate turning point (LTP2). Thereafter, exercise intensity (target heart rate and workload) was calculated and compared between the three methods applied. Patients had significantly reduced maximal exercise capacity (68% ± 21% of predicted V˙O2peak) and chronotropic incompetence (74% ± 7% of predicted peak heart rate). Heart rate, workload, and V˙O2 at HRTP and at RCP were not different, but at LTP2, these parameters were significantly (P < 0.0001) higher. Mean target heart rate and target workload calculated using the LTP2 were 5% and 12% higher compared with those calculated using HRTP and RCP, respectively. The calculation of target heart rate based on LTP2 was 5% and 10% higher in 12 of 48 (25%) and 6 of 48 (12.5%) patients, respectively, compared with the other two methods. In patients with chronic heart failure, RCP and HRTP, determined during cardiopulmonary exercise tests, precede the occurrence of LTP2. Target heart rates and workloads used to prescribe tailored exercise training in patients with chronic heart failure based on LTP2 are significantly higher than those derived from HRTP and RCP.

Distractive Auditory Stimuli in the Form of Music in Individuals With COPD: A Systematic Review.

PubMed

Lee, Annemarie L; Desveaux, Laura; Goldstein, Roger S; Brooks, Dina

2015-08-01

Music has been used as a distractive auditory stimulus (DAS) in patients with COPD, but its effects are unclear. This systematic review aimed to establish the effect of DAS on exercise capacity, symptoms, and health-related quality of life (HRQOL) under three conditions: (1) during exercise training, (2) during exercise testing, and (3) for symptom management at rest. Randomized controlled or crossover trials as well as cohort studies of DAS during exercise training, during formal exercise testing, and for symptom management among individuals with COPD were identified from a search of seven databases. Two reviewers independently assessed study quality. Weighted mean differences (WMDs) with 95% CIs were calculated using a random-effects model. Thirteen studies (12 of which were randomized controlled or crossover trials) in 415 participants were included. DAS increased exercise capacity when applied over at least 2 months of exercise training (WMD, 98 m; 95% CI, 47-150 m). HRQOL improved only after a training duration of 3 months. Less dyspnea was noted with DAS during exercise training, but this was not consistently observed in short-term exercise testing or as a symptom management strategy at rest. DAS appears to reduce symptoms of dyspnea and fatigue when used during exercise training, with benefits observed in exercise capacity and HRQOL. When applied during exercise testing, the effects on exercise capacity and symptoms and as a strategy for symptom management at rest are inconsistent.

Hypercholesterolemia Impairs Exercise Capacity in Mice

PubMed Central

Maxwell, Andrew J.; Niebauer, Josef; Lin, Patrick S.; Tsao, Philip S.; Bernstein, Daniel; Cooke, John P.

2011-01-01

Objective We previously reported an attenuation of both exercise hyperemia and measures of aerobic capacity in hypercholesterolemic mice. In this study we expanded upon the previous findings by examining the temporal and quantitative relationship of hypercholesterolemia to aerobic and anaerobic capacity and by exploring several potential mechanisms of dysfunction. Methods Eight-week old wild type (n=123) and apoE knockout (n=79) C57BL/6J mice were divided into groups with distinct cholesterol levels by feeding regular or high fat diets. At various ages the mice underwent treadmill ergospirometry. To explore mechanisms, aortic ring vasodilator function and nitrate (NOx) activity, urinary excretion of NOx, running muscle microvascular density and citrate synthase activity, as well as myocardial mass and histologic evidence of ischemia were measured. Results At 8 weeks of age, all mice had similar measures of exercise capacity. All indices of aerobic exercise capacity progressively declined at 12 and 20 weeks of age in the hypercholesterolemic mice as cholesterol levels increased while indices of anaerobic capacity remained unaffected. Across the 4 cholesterol groups, the degree of aerobic dysfunction was related to serum cholesterol levels; a relationship that was maintained after correcting for confounding factors. Associated with the deterioration in exercise capacity was a decline in measures of nitric oxide-mediated vascular function while there was no evidence of aberrations in functional or oxidative capacities or in other components of transport capacity. Conclusion Aerobic exercise dysfunction is observed in murine models of genetic and diet-induced hypercholesterolemia and is associated with a reduction in vascular nitric oxide production. PMID:19651675

Brain, Behavior, and Immunity: Effects and potential mechanisms of exercise training on cancer progression: A translational perspective

Cancer.gov

Review of the extant epidemiological evidence examining the association between exercise behavior, function capacity/exercise capacity, and cancer-specific recurrence and mortality as well as all-cause mortality individuals following a cancer diagnosis.

The effects of dance music jump rope exercise on pulmonary function and body mass index after music jump rope exercise in overweight adults in 20's.

PubMed

Seo, KyoChul

2017-08-01

[Purpose] The purpose of this study was to examine the effect of a dance music jump rope exercise on changes Pulmonary Function and body mass index in female overweight subjects in their 20's. [Subjects and Methods] The subjects were randomly assigned to the dance music jump rope exercise group and the stationary cycle exercise group. All subjects have conducted the exercises three times a week for four weeks. Pulmonary function was evaluated using a spirometer, and body mass index was evaluated using an InBody 3.0. [Results] The findings of this study showed significant improvements in the voluntary capacity and body mass index of the experimental groups. Vital capacity was higher in the music jump rope exercise group than the stationary cycle exercise group, and body mass index was lower in the music jump rope exercise group than the stationary cycle exercise group. [Conclusion] This study showed that the dance music jump rope exercise can be used to improve vital capacity and body mass index.

Supervised Phase II Cardiac Exercise Therapy Shortens the Recovery of Exercise Capacity in Patients with Acute Myocardial Infarction

PubMed Central

Lee, Chih-Wei; Wang, Ji-Hung; Hsieh, Jen-Che; Hsieh, Tsung-Cheng; Wu, Yu-Zu; Chen, Tung-Wei; Huang, Chien-Hui

2014-01-01

[Purpose] To investigate the effects of Phase II cardiac exercise therapy (CET) on exercise capacity and changes in coronary risk factors (CRFs) of patients with acute myocardial infarction (AMI). [Subjects] Thirty male subjects with AMI were divided into an experimental group (EG) and a control group (CG). Another 30 age-matched subjects with patent coronary arteries served as a normal-control group (NCG). [Methods] Subjects in EG (n=20) trained using a stationary bicycle for 30 min at their target heart rate twice a week for 8 weeks. Exercise capacity was defined as the maximal metabolic equivalents (METs) that subjects reached during the symptom-limited maximal exercise test. HR, BP and RPP were recorded. Subjects in EG and CG received exercise tests and screening for CRFs at the beginning of, end of, and 3 months after Phase II CET, while subjects in NCG participated only in the 1st test. [Results] METs of CG did not improve until the 3rd test, while RPP at the 2nd test showed a significant increase. However, EG showed increased METs at the 2nd test without increase of RPP, and increased their high density lipoprotein cholesterol (HDL-C) during the follow-up period between the 2nd and 3rd tests. [Conclusion] Phase II CET shortens the recovery time of exercise capacity, helps to maintain the gained exercise capacity and increases HDL-C in phase III. PMID:25276046

Effects of Nordic walking training on exercise capacity and fitness in men participating in early, short-term inpatient cardiac rehabilitation after an acute coronary syndrome--a controlled trial.

PubMed

Kocur, Piotr; Deskur-Smielecka, Ewa; Wilk, Malgorzata; Dylewicz, Piotr

2009-11-01

To investigate the effects of Nordic Walking training supplemental to a standard, early rehabilitation programme on exercise capacity and physical fitness in men after an acute coronary syndrome. A controlled trial. Cardiac rehabilitation service of a provincial hospital. Eighty men 2-3 weeks after an acute coronary syndrome, with good exercise tolerance. Three-week, inpatient cardiac rehabilitation programme (control group) supplemented with Nordic Walking (Nordic Walking group), or with traditional walking training (walking training group). Exercise capacity was assessed as peak energy cost (in metabolic equivalents) in symptom-limited treadmill exercise test, and physical fitness with the Fullerton Functional Fitness Test. Exercise capacity after the rehabilitation programme was higher in the Nordic Walking group than in the control group (10.8 +/- 1.8 versus 9.2 +/- 2.2 metabolic equivalents, P =0.025). The improvement in exercise capacity in the Nordic Walking group was higher than in the control group (1.8 +/- 1.5 versus 0.7 +/- 1.4 metabolic equivalents, P =0.002). In contrast to the control group, the results of all components of the Fullerton test improved in the Nordic Walking and walking training groups. After the programme, lower body endurance, and dynamic balance were significantly better in the Nordic Walking group in comparison with the walking training and control groups, and upper body endurance was significantly better in the Nordic Walking and walking training groups than in the control group. Nordic Walking may improve exercise capacity, lower body endurance and coordination of movements in patients with good exercise tolerance participating in early, short-term rehabilitation after an acute coronary syndrome.

Exercise training improves in vivo endothelial repair capacity of early endothelial progenitor cells in subjects with metabolic syndrome.

PubMed

Sonnenschein, Kristina; Horváth, Tibor; Mueller, Maja; Markowski, Andrea; Siegmund, Tina; Jacob, Christian; Drexler, Helmut; Landmesser, Ulf

2011-06-01

Endothelial dysfunction and injury are considered to contribute considerably to the development and progression of atherosclerosis. It has been suggested that intense exercise training can increase the number and angiogenic properties of early endothelial progenitor cells (EPCs). However, whether exercise training stimulates the capacity of early EPCs to promote repair of endothelial damage and potential underlying mechanisms remain to be determined. The present study was designed to evaluate the effects of moderate exercise training on in vivo endothelial repair capacity of early EPCs, and their nitric oxide and superoxide production as characterized by electron spin resonance spectroscopy analysis in subjects with metabolic syndrome. Twenty-four subjects with metabolic syndrome were randomized to an 8 weeks exercise training or a control group. Superoxide production and nitric oxide (NO) availability of early EPCs were characterized by using electron spin resonance (ESR) spectroscopy analysis. In vivo endothelial repair capacity of EPCs was examined by transplantation into nude mice with defined carotid endothelial injury. Endothelium-dependent, flow-mediated vasodilation was analysed using high-resolution ultrasound. Importantly, exercise training resulted in a substantially improved in vivo endothelial repair capacity of early EPCs (24.0 vs 12.7%; p < 0.05) and improved endothelium-dependent vasodilation. Nitric oxide production of EPCs was substantially increased after exercise training, but not in the control group. Moreover, exercise training reduced superoxide production of EPCs, which was not observed in the control group. The present study suggests for the first time that moderate exercise training increases nitric oxide production of early endothelial progenitor cells and reduces their superoxide production. Importantly, this is associated with a marked beneficial effect on the in vivo endothelial repair capacity of early EPCs in subjects with metabolic syndrome.

Effect of low glycemic index food and postprandial exercise on blood glucose level, oxidative stress and antioxidant capacity.

PubMed

Kasuya, Noriaki; Ohta, Shoichiro; Takanami, Yoshikazu; Kawai, Yukari; Inoue, Yutaka; Murata, Isamu; Kanamoto, Ikuo

2015-04-01

Low glycemic index (GI) food and postprandial exercise are non-drug therapies for improving postprandial hyperglycemia. The present randomized, crossover study investigated the effect of low GI food combined with postprandial exercise on postprandial blood glucose level, oxidative stress and antioxidant capacity. A total of 13 healthy subjects were each used in four experiments: i) rice only (control), ii) salad prior to rice (LGI), iii) exercise following rice (EX) and iv) salad prior to rice and exercise following rice (MIX). The blood glucose level, oxidative stress and antioxidant capacity were then measured. At 60 min after the meal, the blood glucose level was observed to be increased in the MIX group compared with that in the LGI group. Furthermore, at 180 min, the antioxidant capacity was found to be reduced in the MIX group compared with those of the LGI and EX groups. These findings suggest that low GI food combined with postprandial exercise does not improve postprandial hyperglycemia. It may be necessary to establish optimal timing and intensity when combining low GI food with postprandial exercise to improve postprandial hyperglycemia.

Global longitudinal strain by two-dimensional speckle tracking imaging predicts exercise capacity in patients with chronic heart failure.

PubMed

Kou, Seisyou; Suzuki, Kengo; Akashi, Yoshihiro J; Mizukoshi, Kei; Takai, Manabu; Izumo, Masaki; Shimozato, Takashi; Hayashi, Akio; Ohtaki, Eiji; Osada, Naohiko; Omiya, Kazuto; Nobuoka, Sachihiko; Miyake, Fumihiko

2011-06-01

Left ventricular ejection fraction (LVEF) predicts mortality in patients with chronic heart failure (CHF). However, a weak correlation was found between LVEF and peak oxygen uptake ([Formula: see text]) in CHF patients. Global longitudinal strain measured by two-dimensional (2D) strain is regarded as a more useful predictor of cardiac events than LVEF. We investigated whether 2D strain obtained at rest could predict peak [Formula: see text] in patients with CHF. Fifty-one patients (mean age of 54.0 ± 12.0 years, 14 females, LVEF 46.0 ± 15.0%) with stable CHF underwent resting echocardiography and cardiopulmonary exercise testing. Leg muscle strength was measured for the evaluation of peripheral factors. Global longitudinal strain (GLS) in the apical 4-, 3-, and 2-chamber views and global circumferential strain (GCS) in the parasternal mid short-axis view were measured. In all patients, peak [Formula: see text] correlated with leg muscle strength (r = 0.55, p < 0.0001), LVEF (r = 0.46, p < 0.001), GLS (r = -0.45, p < 0.001), and GCS (r = -0.41, p = 0.005), respectively. No significant correlation was found between the ratio of early transmitral velocity to peak early diastolic mitral annulus velocity (E/E') and peak [Formula: see text]. In the patients with heart failure and reduced LVEF, a multiple stepwise linear regression analysis based on leg muscle strength, LVEF, E/E', GLS, and GCS was performed to identify independent predictors of peak [Formula: see text], resulting in leg muscle strength and GLS (R (2) = 0.888) as independent predictors of peak [Formula: see text]. Global longitudinal strain at rest could possibly predict exercise capacity, which appeared to be more useful than LVEF, E/E', and GCS in CHF patients with reduced LVEF.

Effects of new sports tennis type exercise on aerobic capacity, follicle stimulating hormone and N-terminal telopeptide in the postmenopausal women.

PubMed

Shin, Hyun-Jae; Lee, Ha-Yan; Cho, Hye-Young; Park, Yun-Jin; Moon, Hyung-Hoon; Lee, Sung-Hwan; Lee, Sung-Ki; Kim, Myung-Ki

2014-04-01

Menopause is characterized by rapid decreases in bone mineral density, aerobic fitness, muscle strength, and balance. In the present study, we investigated the effects of new sports tennis type exercise on aerobic capacity, follicle stimulating hormone (FSH) and N-terminal telopeptide (NTX) in the postmenopausal women. Subjects were consisted of 20 postmenopausal women, who had not menstruated for at least 1 yr and had follicle-stimulating hormone levels > 35 mIU/L, estradiol levels< 40 pg/mL. The subjects were randomly divided into two groups: control group (n= 10), new sports tennis type exercise group (n= 10). New sports tennis type exercise was consisted of warm up (10 min), new sports tennis type exercise (40 min), cool down (10 min) 3 days a per week for 12 weeks. The aerobic capacities were increased by 12 weeks new sports tennis type exercise. New sports tennis type exercise significantly increased FSH and NTx levels, indicating biochemical markers of bone formation and resorption. These findings indicate that 12 weeks of new sports tennis type exercise can be effective in prevention of bone loss and enhancement of aerobic capacity in postmenopausal women.

Exercise training enhances aerobic capacity in juvenile estuarine crocodiles (Crocodylus porosus).

PubMed

Owerkowicz, Tomasz; Baudinette, Russell V

2008-06-01

Aerobic capacity (VO2max) of endothermic vertebrates is known to increase with exercise training, but this effect has not been found to-date in non-avian reptiles. We exercised juvenile estuarine crocodiles (Crocodylus porosus) to walk at 0.75-0.88 km/h on a treadmill for up to 20 min a day over 16 weeks, and compared their aerobic performance with that of unexercised crocodiles. In the exercised group, VO2max increased from 6.9 to 8.5 mLO2/kg/min (+28%), and locomotor endurance increased from 3.8 to 6.9 min (+82%). Neither VO2max nor endurance changed significantly in the sedentary group. This finding extends the exercise training effect onto another vertebrate clade, and demonstrates that ectothermic amniotes are capable of elevating their aerobic capacity in response to exercise training. We propose that differences in cardiopulmonary structure and function in non-avian reptiles may be responsible for the absence (in squamates) or presence (in crocodilians) of a strong training effect on aerobic capacity.

Obesity-associated metabolic changes influence resting and peak heart rate in women and men.

PubMed

Strandheim, Astrid; Halland, Hilde; Saeed, Sahrai; Cramariuc, Dana; Hetland, Trude; Lønnebakken, Mai Tone; Gerdts, Eva

2015-01-01

To study the relationship between obesity and heart rate (HR) in women and men. We studied 241 overweight and obese subjects without known heart disease. All subjects underwent ergospirometry during maximal exercise testing on treadmill and recording of body composition, electrocardiogram and clinic and ambulatory blood pressure. Women (n = 132) were slightly older and had higher fat mass, but lower weight, blood pressure and prevalence of metabolic syndrome (MetS) than men (n = 109) (all p < 0.05), while prevalences of obesity and hypertension did not differ. A significant interaction between sex and HR was demonstrated (p < 0.05). In multivariate analysis, female sex (β = 0.99, p < 0.01) predicted higher resting HR independent of confounders. Higher resting HR was particularly associated with presence of MetS, hypertension, higher insulin resistance and lower relative muscle mass in men (all p < 0.05). Female sex also predicted higher peak exercise HR (β = 0.48, p < 0.01) independent of confounders. Higher peak exercise HR was particularly associated with higher exercise capacity and lower age and self-reported physical activity in men, while lower HbA1c and absence of obesity were the main covariates in women in multivariate analyses (all p < 0.05). In our study population, obesity and obesity-associated metabolic changes influenced both resting and peak exercise HR.

Cardiovascular rehabilitation soon after stroke using feedback-controlled robotics-assisted treadmill exercise: study protocol of a randomised controlled pilot trial

PubMed Central

2013-01-01

Background After experiencing a stroke, most individuals also suffer from cardiac disease, are immobile and thus have low endurance for exercise. Aerobic capacity is seriously reduced in these individuals and does not reach reasonable levels after conventional rehabilitation programmes. Cardiovascular exercise is beneficial for improvement of aerobic capacity in mild to moderate stroke. However, less is known about its impact on aerobic capacity, motor recovery, and quality-of-life in severely impaired individuals. The aim of this pilot study is to explore the clinical efficacy and feasibility of cardiovascular exercise with regard to aerobic capacity, motor recovery, and quality-of-life using feedback-controlled robotics-assisted treadmill exercise in non-ambulatory individuals soon after experiencing a stroke. Methods/Design This will be a single-centred single blind, randomised control trial with a pre-post intervention design. Subjects will be recruited early after their first stroke (≤20 weeks) at a neurological rehabilitation clinic and will be randomly allocated to an inpatient cardiovascular exercise programme that uses feedback-controlled robotics-assisted treadmill exercise (experimental) or to conventional robotics-assisted treadmill exercise (control). Intervention duration depends on the duration of each subject’s inpatient rehabilitation period. Aerobic capacity, as the primary outcome measure, will be assessed using feedback-controlled robotics-assisted treadmill-based cardiopulmonary exercise testing. Secondary outcome measures will include gait speed, walking endurance, standing function, and quality-of-life. Outcome assessment will be conducted at baseline, after each 4-week intervention period, and before clinical discharge. Ethical approval has been obtained. Discussion Whether cardiovascular exercise in non-ambulatory individuals early after stroke has an impact on aerobic capacity, motor recovery, and quality-of-life is not yet known. Feedback-controlled robotics-assisted treadmill exercise is a relatively recent intervention method and might be used to train and evaluate aerobic capacity in this population. The present pilot trial is expected to provide new insights into the implementation of early cardiovascular exercise for individuals with severe motor impairment. The findings of this study may guide future research to explore the effects of early cardiovascular activation after severe neurological events. Trial registration This trial is registered with the Clinical Trials.gov Registry (NCT01679600). PMID:24053609

Oxygen radical absorbance capacity (ORAC) and exercise-induced oxidative stress in trotters.

PubMed

Kinnunen, Susanna; Hyyppä, Seppo; Lehmuskero, Arja; Oksala, Niku; Mäenpää, Pekka; Hänninen, Osmo; Atalay, Mustafa

2005-12-01

Strenuous exercise is a potent inducer of oxidative stress, which has been suggested to be associated with disturbances in muscle homeostasis, fatigue and injury. There is no comprehensive or uniform view of the antioxidant status in horses. We have previously shown that moderate exercise induces protein oxidation in trotters. The aim of this study was to measure the antioxidative capacity of the horse in relation to different antioxidant components and oxidative stress markers after a single bout of moderate exercise to elucidate the mechanisms of antioxidant protection in horses. Eight clinically normal and regularly trained standard-bred trotters were treadmill-exercised for 53 min at moderate intensity. Blood samples were collected prior to and immediately after exercise and at 4 and 24 h of recovery. Muscle biopsies from the middle gluteal muscle were taken before exercise and after 4 h of recovery. Acute induction of oxygen radical absorbance capacity (ORAC) did not prevent exercise-induced oxidative stress, which was demonstrated by increased lipid hydroperoxides (LPO). Pre-exercise ORAC levels were, however, a determinant of total glutathione content of the blood after 4 and 24 h of recovery. Furthermore, baseline ORAC level correlated negatively with 4-h recovery LPO levels. Our results imply that horses are susceptible to oxidative stress, but a stronger antioxidant capacity may improve coping with exercise-induced oxidative stress.

Reliability, construct validity and determinants of 6-minute walk test performance in patients with chronic heart failure.

PubMed

Uszko-Lencer, Nicole H M K; Mesquita, Rafael; Janssen, Eefje; Werter, Christ; Brunner-La Rocca, Hans-Peter; Pitta, Fabio; Wouters, Emiel F M; Spruit, Martijn A

2017-08-01

In-depth analyses of the measurement properties of the 6-minute walk test (6MWT) in patients with chronic heart failure (CHF) are lacking. We investigated the reliability, construct validity, and determinants of the distance covered in the 6MWT (6MWD) in CHF patients. 337 patients were studied (median age 65years, 70% male, ejection fraction 35%). Participants performed two 6MWTs on subsequent days. Demographics, anthropometrics, clinical data, ejection fraction, maximal exercise capacity, body composition, lung function, and symptoms of anxiety and depression were also assessed. Construct validity was assessed in terms of convergent, discriminant and known-groups validity. Stepwise linear regression was used. 6MWT was reliable (ICC=0.90, P<0.0001). The learning effect was 31m (95%CI 27, 35m). Older age (≥65years), lower lung diffusing capacity (<80% predicted) and higher NYHA class (NYHA III) were associated with a lower likelihood of a meaningful increase in the second test (OR 0.45-0.56, P<0.05 for all). The best 6MWD had moderate-to-good correlations with peak exercise capacity (r s =0.54-0.69) and no-to-fair correlations with body composition, lung function, ejection fraction, and symptoms of anxiety and depression (r s =0.04-0.49). Patients with higher NYHA classes had lower 6MWD. 6MWD was independently associated with maximal power output during maximal exercise, estimated glomerular filtration rate and age (51.7% of the variability). 6MWT was found to be reliable and valid in patients with mild-to-moderate CHF. Maximal exercise capacity, renal function and age were significant determinants of the best 6MWD. These findings strengthen the clinical utility of the 6MWT in CHF. Copyright © 2017 Elsevier B.V. All rights reserved.

Daily Supine LBNP Treadmill Exercise Maintains Upright Exercise Capacity During 14 Days of Bed Rest

NASA Technical Reports Server (NTRS)

Ertl, Andy C.; Watenpaugh, D. E.; Hargens, Alan R.; Fortney, S. M.; Lee, S. M. C.; Ballard, R. E.; William, J. M.

1996-01-01

Exposure to microgravity or bed rest reduces upright exercise capacity. Exercise modes, durations, and intensities which will effectively and efficiently counteract such deconditioning are presently unresolved. We that daily supine treadmill interval training with lower body negative pressure (LBNP) would prevent reduction in upright exercise capacity during 14 days of 6 deg. head-down bed rest (BR). Eight healthy male subjects underwent two 14 day BR protocols separated by 3 months. In a crossover design, subjects either remained at strict BR or performed 40 min of daily exercise consisting of supine walking and running at intensities varying from 40-80% of pre-BR upright peak oxygen uptake (VO2). LBNP during supine exercise was used to provide 1.0 to 1.2 times body weight of footward force. An incremental upright treadmill test to measure submaximal and peak exercise responses was given pre- and post-BR. In the non-exercise condition, peak VO2 and time to exhaustion were reduced 16 +/- 4% and 10 +/- 1% (p less than 0.05), respectively, from pre-BR. With LBNP exercise these variables were not significantly different (NS) from pre-BR. During submaximal treadmill speeds after BR, heart rate was higher (11 +/- 11 bpm, p less than 0.05) and respiratory exchange ratio was elevated (p less than 0.05) in the no exercise condition. Both were maintained at pre-BR levels in the LBNP exercise condition (NS from pre-BR). Since this supine treadmill interval training with addition of LBNP maintained upright exercise responses and capacity during BR, this countermeasure may also be effective during space flight.

Exercise Capacity and Response to Training Quantitative Trait Loci in a NZW X 129S1 Intercross and Combined Cross Analysis of Inbred Mouse Strains

PubMed Central

Massett, Michael P.; Avila, Joshua J.; Kim, Seung Kyum

2015-01-01

Genetic factors determining exercise capacity and the magnitude of the response to exercise training are poorly understood. The aim of this study was to identify quantitative trait loci (QTL) associated with exercise training in mice. Based on marked differences in training responses in inbred NZW (-0.65 ± 1.73 min) and 129S1 (6.18 ± 3.81 min) mice, a reciprocal intercross breeding scheme was used to generate 285 F2 mice. All F2 mice completed an exercise performance test before and after a 4-week treadmill running program, resulting in an increase in exercise capacity of 1.54 ± 3.69 min (range = -10 to +12 min). Genome-wide linkage scans were performed for pre-training, post-training, and change in run time. For pre-training exercise time, suggestive QTL were identified on Chromosomes 5 (57.4 cM, 2.5 LOD) and 6 (47.8 cM, 2.9 LOD). A significant QTL for post-training exercise capacity was identified on Chromosome 5 (43.4 cM, 4.1 LOD) and a suggestive QTL on Chromosomes 1 (55.7 cM, 2.3 LOD) and 8 (66.1 cM, 2.2 LOD). A suggestive QTL for the change in run time was identified on Chromosome 6 (37.8 cM, 2.7 LOD). To identify shared QTL, this data set was combined with data from a previous F2 cross between B6 and FVB strains. In the combined cross analysis, significant novel QTL for pre-training exercise time and change in exercise time were identified on Chromosome 12 (54.0 cM, 3.6 LOD) and Chromosome 6 (28.0 cM, 3.7 LOD), respectively. Collectively, these data suggest that combined cross analysis can be used to identify novel QTL and narrow the confidence interval of QTL for exercise capacity and responses to training. Furthermore, these data support the use of larger and more diverse mapping populations to identify the genetic basis for exercise capacity and responses to training. PMID:26710100

Exercise Capacity and Selected Physiological Factors by Ancestry and Residential Altitude: Cross-Sectional Studies of 9–10-Year-Old Children in Tibet

PubMed Central

Berntsen, Sveinung; Andersen, Lars Bo; Stigum, Hein; Ouzhuluobu; Nafstad, Per; Wu, Tianyi; Bjertness, Espen

2014-01-01

Abstract Bianba, Sveinung Bernsten, Lars Bo Andersen, Hein Stegum, Ouzhuluobu, Per Nafstad, Tianyi Wu, and Espen Bjertness. Exercise capacity and selected physiological factors by ancestry and residential altitude—Cross-sectional studies of 9–10-year-old children in Tibet. High Alt Med Biol. 15:162–169, 2014.—Aim: Several physiological compensatory mechanisms have enabled Tibetans to live and work at high altitude, including increased ventilation and pulmonary diffusion capacity, both of which serve to increase oxygen transport in the blood. The aim of the present study was to compare exercise capacity (maximal power output) and selected physiological factors (arterial oxygen saturation and heart rate at rest and during maximal exercise, resting hemoglobin concentration, and forced vital capacity) in groups of native Tibetan children living at different residential altitudes (3700 vs. 4300 m above sea level) and across ancestry (native Tibetan vs. Han Chinese children living at the same altitude of 3700 m). Methods: A total of 430 9–10-year-old native Tibetan children from Tingri (4300 m) and 406 native Tibetan- and 406 Han Chinese immigrants (77% lowland-born and 33% highland-born) from Lhasa (3700 m) participated in two cross-sectional studies. The maximal power output (Wmax) was assessed using an ergometer cycle. Results: Lhasa Tibetan children had a 20% higher maximal power output (watts/kg) than Tingri Tibetan and 4% higher than Lhasa Han Chinese. Maximal heart rate, arterial oxygen saturation at rest, lung volume, and arterial oxygen saturation were significantly associated with exercise capacity at a given altitude, but could not fully account for the differences in exercise capacity observed between ancestry groups or altitudes. Conclusions: The superior exercise capacity in native Tibetans vs. Han Chinese may reflect a better adaptation to life at high altitude. Tibetans at the lower residential altitude of 3700 m demonstrated a better exercise capacity than residents at a higher altitude of 4300 m when measured at their respective residential altitudes. Such altitude- or ancestry-related difference could not be fully attributed to the physiological factors measured. PMID:24836751

A "Wii" bit of fun: the effects of adding Nintendo Wii(®) Bowling to a standard exercise regimen for residents of long-term care with upper extremity dysfunction.

PubMed

Hsu, Jason K; Thibodeau, Richard; Wong, Stephanie J; Zukiwsky, Daniel; Cecile, Sara; Walton, David M

2011-04-01

The aims of this randomized, single-blind crossover trial were to investigate the effect of adding a simulated bowling video game via the Nintendo Wii(®) gaming system to the standard exercise regimen of cognitively intact residents of long-term care (LTC) with upper extremity dysfunction and to identify individual characteristics that might predict improvement. Residents (n=34) were recruited through two LTC facilities in southwestern Ontario and were randomized into a standard exercise (SG) or standard exercise plus Wii bowling (Wii) arm. After 4 weeks of intervention, the groups were crossed over to the opposite arm. Outcomes included measures of pain intensity and bothersomeness, physical activity enjoyment, and a six-item measure of functional capacity designed specifically for residents of LTC. Results suggest that subjects improved on all outcomes from pre- to postintervention but that only enjoyment of activity showed a significant difference between the SG and Wii groups. Effect sizes (Cohen's d) ranged from small (0.30 for bothersomeness) to large (1.77 for functional capacity). Responders, defined as those subjects who reported any degree of improvement following the Wii intervention, were less likely to complain of stiffness or shoulder symptoms and were more likely to complain of hand symptoms than non-responders. Limitations in interpretation and recommendations for future research are presented.

The effect of supine exercise on the distribution of regional pulmonary blood flow measured using proton MRI

PubMed Central

Hall, E. T.; Sá, R. C.; Holverda, S.; Arai, T. J.; Dubowitz, D. J.; Theilmann, R. J.; Prisk, G. K.

2013-01-01

The Zone model of pulmonary perfusion predicts that exercise reduces perfusion heterogeneity because increased vascular pressure redistributes flow to gravitationally nondependent lung, and causes dilation and recruitment of blood vessels. However, during exercise in animals, perfusion heterogeneity as measured by the relative dispersion (RD, SD/mean) is not significantly decreased. We evaluated the effect of exercise on pulmonary perfusion in six healthy supine humans using magnetic resonance imaging (MRI). Data were acquired at rest, while exercising (∼27% of maximal oxygen consumption) using a MRI-compatible ergometer, and in recovery. Images were acquired in most of the right lung in the sagittal plane at functional residual capacity, using a 1.5-T MR scanner equipped with a torso coil. Perfusion was measured using arterial spin labeling (ASL-FAIRER) and regional proton density using a fast multiecho gradient-echo sequence. Perfusion images were corrected for coil-based signal heterogeneity, large conduit vessels removed and quantified (in ml·min−1·ml−1) (perfusion), and also normalized for density and quantified (in ml·min−1·g−1) (density-normalized perfusion, DNP) accounting for tissue redistribution. DNP increased during exercise (11.1 ± 3.5 rest, 18.8 ± 2.3 exercise, 13.2 ± 2.2 recovery, ml·min−1·g−1, P < 0.0001), and the increase was largest in nondependent lung (110 ± 61% increase in nondependent, 63 ± 35% in mid, 70 ± 33% in dependent, P < 0.005). The RD of perfusion decreased with exercise (0.93 ± 0.21 rest, 0.73 ± 0.13 exercise, 0.94 ± 0.18 recovery, P < 0.005). The RD of DNP showed a similar trend (0.82 ± 0.14 rest, 0.75 ± 0.09 exercise, 0.81 ± 0.10 recovery, P = 0.13). In conclusion, in contrast to animal studies, in supine humans, mild exercise decreased perfusion heterogeneity, consistent with Zone model predictions. PMID:24356515

[Improvement in quality of life and exercise capacity without muscular biology changes after general training in patients with severe chronic obstructive pulmonary disease].

PubMed

Pascual-Guardia, Sergio; Wodja, Emil; Gorostiza, Amaya; López de Santamaría, Elena; Gea, Joaquim; Gáldiz, Juan B; Sliwinski, Pawel; Barreiro, Esther

2013-03-02

Despite the beneficial effects of exercise training in chronic obstructive pulmonary disease (COPD) patients, several studies have revealed functional and biological abnormalities in their peripheral muscles. The objective was to determine whether exercise training of high intensity and long duration modifies oxidative stress levels and structure of respiratory and peripheral muscles of severe COPD patients, while also improving their exercise capacity and quality of life. Multicenter study (Warsaw and Barakaldo) in which 25 severe COPD out-patients were recruited from the COPD clinics. In all patients, lung and muscle functions, exercise capacity (walking test and cycloergometer) and quality of life (QoL) were assessed, and open muscle biopsies from the vastus lateralis and external intercostals (n=14) were obtained before and after an exercise training program of high intensity (respiratory rehabilitation area, 70% maximal tolerated load in a cycloergometer) and long duration (10 weeks). Oxidative stress and muscle structural modifications were evaluated in all muscle biopsies using immunoblotting and immunohistochemistry. In all patients, after the training program, without any drop-outs, exercise capacity and QoL improved significantly, whereas oxidative stress, muscle damage and structure were not modified in their respiratory or limb muscles compared to baseline. In patients with severe COPD, exercise training of high intensity and long duration significantly improves their exercise capacity and QoL, without inducing significant modifications on oxidative stress levels or muscle structure in their respiratory or peripheral muscles. These results may have future clinical therapeutic implications. Copyright © 2011 Elsevier España, S.L. All rights reserved.

The influence of training characteristics on the effect of aerobic exercise training in patients with chronic heart failure: A meta-regression analysis.

PubMed

Vromen, T; Kraal, J J; Kuiper, J; Spee, R F; Peek, N; Kemps, H M

2016-04-01

Although aerobic exercise training has shown to be an effective treatment for chronic heart failure patients, there has been a debate about the design of training programs and which training characteristics are the strongest determinants of improvement in exercise capacity. Therefore, we performed a meta-regression analysis to determine a ranking of the individual effect of the training characteristics on the improvement in exercise capacity of an aerobic exercise training program in chronic heart failure patients. We focused on four training characteristics; session frequency, session duration, training intensity and program length, and their product; total energy expenditure. A systematic literature search was performed for randomized controlled trials comparing continuous aerobic exercise training with usual care. Seventeen unique articles were included in our analysis. Total energy expenditure appeared the only training characteristic with a significant effect on improvement in exercise capacity. However, the results were strongly dominated by one trial (HF-action trial), accounting for 90% of the total patient population and showing controversial results compared to other studies. A repeated analysis excluding the HF-action trial confirmed that the increase in exercise capacity is primarily determined by total energy expenditure, followed by session frequency, session duration and session intensity. These results suggest that the design of a training program requires high total energy expenditure as a main goal. Increases in training frequency and session duration appear to yield the largest improvement in exercise capacity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Size, shape, and stamina: the impact of left ventricular geometry on exercise capacity.

PubMed

Lam, Carolyn S P; Grewal, Jasmine; Borlaug, Barry A; Ommen, Steve R; Kane, Garvan C; McCully, Robert B; Pellikka, Patricia A

2010-05-01

Although several studies have examined the cardiac functional determinants of exercise capacity, few have investigated the effects of structural remodeling. The current study evaluated the association between cardiac geometry and exercise capacity. Subjects with ejection fraction > or = 50% and no valvular disease, myocardial ischemia, or arrhythmias were identified from a large prospective exercise echocardiography database. Left ventricular mass index and relative wall thickness were used to classify geometry into normal, concentric remodeling, eccentric hypertrophy, and concentric hypertrophy. All of the subjects underwent symptom-limited treadmill exercise according to standard Bruce protocol. Maximal exercise tolerance was measured in metabolic equivalents. Of 366 (60+/-14 years; 57% male) subjects, 166 (45%) had normal geometry, 106 (29%) had concentric remodeling, 40 (11%) had eccentric hypertrophy, and 54 (15%) had concentric hypertrophy. Geometry was related to exercise capacity: in descending order, the maximum achieved metabolic equivalents were 9.9+/-2.8 in normal, 8.9+/-2.6 in concentric remodeling, 8.6+/-3.1 in eccentric hypertrophy, and 8.0+/-2.7 in concentric hypertrophy (all P<0.02 versus normal). Left ventricular mass index and relative wall thickness were negatively correlated with exercise tolerance in metabolic equivalents (r=-0.14; P=0.009 and r=-0.21; P<0.001, respectively). Augmentation of heart rate and ejection fraction with exercise were blunted in concentric hypertrophy compared with normal, even after adjusting for medications. In conclusion, the pattern of ventricular remodeling is related to exercise capacity among low-risk adults. Subjects with concentric hypertrophy display the greatest limitation, and this is related to reduced systolic and chronotropic reserve. Reverse remodeling strategies may prevent or treat functional decline in patients with structural heart disease.

Size, Shape and Stamina: The Impact of Left Ventricular Geometry on Exercise Capacity

PubMed Central

Lam, Carolyn S.P.; Grewal, Jasmine; Borlaug, Barry A.; Ommen, Steve R.; Kane, Garvan C.; McCully, Robert B.; Pellikka, Patricia A.

2010-01-01

While several studies have examined the cardiac functional determinants of exercise capacity, few have investigated the effects of structural remodeling. The current study evaluated the association between cardiac geometry and exercise capacity. Subjects with ejection fraction ≥ 50% and no valvular disease, myocardial ischemia or arrhythmias were identified from a large prospective exercise echocardiography database. Left ventricular mass index and relative wall thickness were used to classify geometry into normal, concentric remodeling, eccentric hypertrophy and concentric hypertrophy. All subjects underwent symptom-limited treadmill exercise according to standard Bruce protocol. Maximal exercise tolerance was measured in metabolic equivalents. Of 366 (60±14 years; 57% male) subjects, 166(45%) had normal geometry, 106(29%) had concentric remodeling, 40(11%) had eccentric hypertrophy and 54(15%) had concentric hypertrophy. Geometry was related to exercise capacity: in descending order, the maximum achieved metabolic equivalents was 9.9±2.8 in normal, 8.9±2.6 in concentric remodeling, 8.6±3.1 in eccentric hypertrophy and 8.0±2.7 in concentric hypertrophy (all p<0.02 vs normal). Left ventricular mass index and relative wall thickness were negatively correlated with exercise tolerance in metabolic equivalents (r= -0.14; p=0.009 and r= -0.21; p<0.001, respectively). Augmentation of heart rate and ejection fraction with exercise were blunted in concentric hypertrophy compared to normal, even after adjusting for medications. In conclusion, the pattern of ventricular remodeling is related to exercise capacity among low-risk adults. Subjects with concentric hypertrophy display the greatest limitation and this is related to reduced systolic and chronotropic reserve. Reverse remodeling strategies may prevent or treat functional decline in patients with structural heart disease. PMID:20215563

The effect of cooling prior to and during exercise on exercise performance and capacity in the heat: a meta-analysis.

PubMed

Tyler, Christopher James; Sunderland, Caroline; Cheung, Stephen S

2015-01-01

Exercise is impaired in hot, compared with moderate, conditions. The development of hyperthermia is strongly linked to the impairment and as a result various strategies have been investigated to combat this condition. This meta-analysis focused on the most popular strategy: cooling. Precooling has received the most attention but recently cooling applied during the bout of exercise has been investigated and both were reviewed. We conducted a literature search and retrieved 28 articles which investigated the effect of cooling administered either prior to (n=23) or during (n=5) an exercise test in hot (wet bulb globe temperature >26°C) conditions. Mean and weighted effect size (Cohen's d) were calculated. Overall, precooling has a moderate (d=0.73) effect on subsequent performance but the magnitude of the effect is dependent on the nature of the test. Sprint performance is impaired (d=-0.26) but intermittent performance and prolonged exercise are both improved following cooling (d=0.47 and d=1.91, respectively). Cooling during exercise has a positive effect on performance and capacity (d=0.76). Improvements were observed in studies with and without cooling-induced physiological alterations, and the literature supports the suggestion of a dose-response relationship among cooling, thermal strain and improvements in performance and capacity. In summary, precooling can improve subsequent intermittent and prolonged exercise performance and capacity in a hot environment but sprint performance is impaired. Cooling during exercise also has a positive effect on exercise performance and capacity in a hot environment. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

L-Arginine supplementation improves antioxidant defenses through L-arginine/nitric oxide pathways in exercised rats.

PubMed

Shan, Lingling; Wang, Bin; Gao, Guizhen; Cao, Wengen; Zhang, Yunkun

2013-10-15

l-Arginine (l-Arg) supplementation has been shown to enhance physical exercise capacity and delay onset of fatigue. This work investigated the potential beneficial mechanism(s) of l-Arg supplementation by examining its effect on the cellular oxidative and nitrosative stress pathways in the exercised rats. Forty-eight rats were randomly divided into six groups: sedentary control; sedentary control with l-Arg treatment; endurance training (daily swimming training for 8 wk) control; endurance training with l-Arg treatment; an exhaustive exercise (one time swimming to fatigue) control; and an exhaustive exercise with l-Arg treatment. l-Arg (500 mg/kg body wt) or saline was given to rats by intragastric administration 1 h before the endurance training and the exhaustive swimming test. Expression levels and activities of the l-Arg/nitric oxide (NO) pathway components and parameters of the oxidative stress and antioxidant defense capacity were investigated in l-Arg-treated and control rats. The result show that the l-Arg supplementation completely reversed the exercise-induced activation of NO synthase and superoxide dismutase, increased l-Arg transport capacity, and increased NO and anti-superoxide anion levels. These data demonstrate that l-Arg supplementation effectively reduces the exercise-induced imbalance between oxidative stress and antioxidant defense capacity, and this modulation is likely mediated through the l-Arg/NO pathways. The findings of this study improved our understanding of how l-Arg supplementation prevents elevations of reactive oxygen species and favorably enhances the antioxidant defense capacity during physical exercise.

Relationship of fatigue and exercise capacity with emotional and physical state in patients with coronary artery disease admitted for rehabilitation program.

PubMed

Bunevicius, Adomas; Stankus, Albinas; Brozaitiene, Julija; Girdler, Susan S; Bunevicius, Robertas

2011-08-01

The relationship between subjective fatigue, exercise capacity, and symptoms of depression and anxiety in patients with coronary artery disease (CAD) needs to be specified. In this cross-sectional study, a total of 1,470 (64% men; mean age 57 ± 11 years) consecutive CAD patients admitted for cardiac rehabilitation after treatment of acute cardiac events were evaluated for demographic characteristics, for past and current diagnosis and treatment, for New York Heart Association (NYHA) class, for symptoms of depression and for symptoms of anxiety using the Hospital Anxiety and Depression Scale, and for subjective fatigue using the Multidimensional Fatigue Inventory. On the next day, all patients underwent exercise capacity evaluation using a standard bicycle ergometer testing procedure. In univariate regression analyses, there was the strongest positive association between scores on all Multidimensional Fatigue Inventory subscales and scores on the Hospital Anxiety and Depression Scale depression and anxiety subscales and between exercise capacity and NYHA class. Multivariate regression analyses revealed that symptoms of depression were the strongest positive determinants of all dimensions of subjective fatigue and, together with other significant variables, accounted for 17% to 29% of the variance. However, neither depressive nor anxious symptoms were significant determinants of exercise capacity. The association between subjective fatigue and exercise capacity and vice versa was minimal. Subjective fatigue in CAD patients is strongly related to symptoms of depression and symptoms of anxiety. In contrast, exercise capacity in CAD patients is strongly related to NYHA functional class, with no relationship to symptoms of depression and anxiety. Copyright © 2011 Mosby, Inc. All rights reserved.

Effects of aerobic training combined with respiratory muscle stretching on the functional exercise capacity and thoracoabdominal kinematics in patients with COPD: a randomized and controlled trial.

PubMed

Wada, Juliano T; Borges-Santos, Erickson; Porras, Desiderio Cano; Paisani, Denise M; Cukier, Alberto; Lunardi, Adriana C; Carvalho, Celso Rf

2016-01-01

Patients with COPD present a major recruitment of the inspiratory muscles, predisposing to chest incoordination, increasing the degree of dyspnea and impairing their exercise capacity. Stretching techniques could decrease the respiratory muscle activity and improve their contractile capacity; however, the systemic effects of stretching remain unknown. The aim of this study was to evaluate the effects of aerobic training combined with respiratory muscle stretching on functional exercise capacity and thoracoabdominal kinematics in patients with COPD. This study was a randomized and controlled trial. A total of 30 patients were allocated to a treatment group (TG) or a control group (CG; n=15, each group). The TG was engaged in respiratory muscle stretching and the CG in upper and lower limb muscle stretching. Both groups performed 24 sessions (twice a week, 12 weeks) of aerobic training. Functional exercise capacity (6-minute walk test), thoracoabdominal kinematics (optoelectronic plethysmography), and respiratory muscle activity (surface electromyography) were evaluated during exercise. Analysis of covariance was used to compare the groups at a significance level of 5%. After the intervention, the TG showed improved abdominal (ABD) contribution, compartmental volume, mobility, and functional exercise capacity with decreased dyspnea when compared with the CG ( P <0.01). The TG also showed a decreased respiratory muscle effort required to obtain the same pulmonary volume compared to the CG ( P <0.001). Our results suggest that aerobic training combined with respiratory muscle stretching increases the functional exercise capacity with decreased dyspnea in patients with COPD. These effects are associated with an increased efficacy of the respiratory muscles and participation of the ABD compartment.

Motor Skills and Exercise Capacity Are Associated with Objective Measures of Cognitive Functions and Academic Performance in Preadolescent Children.

PubMed

Geertsen, Svend Sparre; Thomas, Richard; Larsen, Malte Nejst; Dahn, Ida Marie; Andersen, Josefine Needham; Krause-Jensen, Matilde; Korup, Vibeke; Nielsen, Claus Malta; Wienecke, Jacob; Ritz, Christian; Krustrup, Peter; Lundbye-Jensen, Jesper

2016-01-01

To investigate associations between motor skills, exercise capacity and cognitive functions, and evaluate how they correlate to academic performance in mathematics and reading comprehension using standardised, objective tests. This cross-sectional study included 423 Danish children (age: 9.29±0.35 years, 209 girls). Fine and gross motor skills were evaluated in a visuomotor accuracy-tracking task, and a whole-body coordination task, respectively. Exercise capacity was estimated from the Yo-Yo intermittent recovery level 1 children's test (YYIR1C). Selected tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to assess different domains of cognitive functions, including sustained attention, spatial working memory, episodic and semantic memory, and processing speed. Linear mixed-effects models were used to investigate associations between these measures and the relationship with standard tests of academic performance in mathematics and reading comprehension. Both fine and gross motor skills were associated with better performance in all five tested cognitive domains (all P<0.001), whereas exercise capacity was only associated with better sustained attention (P<0.046) and spatial working memory (P<0.038). Fine and gross motor skills (all P<0.001), exercise capacity and cognitive functions such as working memory, episodic memory, sustained attention and processing speed were all associated with better performance in mathematics and reading comprehension. The data demonstrate that fine and gross motor skills are positively correlated with several aspects of cognitive functions and with academic performance in both mathematics and reading comprehension. Moreover, exercise capacity was associated with academic performance and performance in some cognitive domains. Future interventions should investigate associations between changes in motor skills, exercise capacity, cognitive functions, and academic performance to elucidate the causality of these associations.

Motor Skills and Exercise Capacity Are Associated with Objective Measures of Cognitive Functions and Academic Performance in Preadolescent Children

PubMed Central

Thomas, Richard; Larsen, Malte Nejst; Dahn, Ida Marie; Andersen, Josefine Needham; Krause-Jensen, Matilde; Korup, Vibeke; Nielsen, Claus Malta; Wienecke, Jacob; Ritz, Christian; Krustrup, Peter; Lundbye-Jensen, Jesper

2016-01-01

Objective To investigate associations between motor skills, exercise capacity and cognitive functions, and evaluate how they correlate to academic performance in mathematics and reading comprehension using standardised, objective tests. Methods This cross-sectional study included 423 Danish children (age: 9.29±0.35 years, 209 girls). Fine and gross motor skills were evaluated in a visuomotor accuracy-tracking task, and a whole-body coordination task, respectively. Exercise capacity was estimated from the Yo-Yo intermittent recovery level 1 children's test (YYIR1C). Selected tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to assess different domains of cognitive functions, including sustained attention, spatial working memory, episodic and semantic memory, and processing speed. Linear mixed-effects models were used to investigate associations between these measures and the relationship with standard tests of academic performance in mathematics and reading comprehension. Results Both fine and gross motor skills were associated with better performance in all five tested cognitive domains (all P<0.001), whereas exercise capacity was only associated with better sustained attention (P<0.046) and spatial working memory (P<0.038). Fine and gross motor skills (all P<0.001), exercise capacity and cognitive functions such as working memory, episodic memory, sustained attention and processing speed were all associated with better performance in mathematics and reading comprehension. Conclusions The data demonstrate that fine and gross motor skills are positively correlated with several aspects of cognitive functions and with academic performance in both mathematics and reading comprehension. Moreover, exercise capacity was associated with academic performance and performance in some cognitive domains. Future interventions should investigate associations between changes in motor skills, exercise capacity, cognitive functions, and academic performance to elucidate the causality of these associations. PMID:27560512

Effects of aerobic training combined with respiratory muscle stretching on the functional exercise capacity and thoracoabdominal kinematics in patients with COPD: a randomized and controlled trial

PubMed Central

Wada, Juliano T; Borges-Santos, Erickson; Porras, Desiderio Cano; Paisani, Denise M; Cukier, Alberto; Lunardi, Adriana C; Carvalho, Celso RF

2016-01-01

Background Patients with COPD present a major recruitment of the inspiratory muscles, predisposing to chest incoordination, increasing the degree of dyspnea and impairing their exercise capacity. Stretching techniques could decrease the respiratory muscle activity and improve their contractile capacity; however, the systemic effects of stretching remain unknown. Objective The aim of this study was to evaluate the effects of aerobic training combined with respiratory muscle stretching on functional exercise capacity and thoracoabdominal kinematics in patients with COPD. Design This study was a randomized and controlled trial. Participants A total of 30 patients were allocated to a treatment group (TG) or a control group (CG; n=15, each group). Intervention The TG was engaged in respiratory muscle stretching and the CG in upper and lower limb muscle stretching. Both groups performed 24 sessions (twice a week, 12 weeks) of aerobic training. Evaluations Functional exercise capacity (6-minute walk test), thoracoabdominal kinematics (optoelectronic plethysmography), and respiratory muscle activity (surface electromyography) were evaluated during exercise. Analysis of covariance was used to compare the groups at a significance level of 5%. Results After the intervention, the TG showed improved abdominal (ABD) contribution, compartmental volume, mobility, and functional exercise capacity with decreased dyspnea when compared with the CG (P<0.01). The TG also showed a decreased respiratory muscle effort required to obtain the same pulmonary volume compared to the CG (P<0.001). Conclusion Our results suggest that aerobic training combined with respiratory muscle stretching increases the functional exercise capacity with decreased dyspnea in patients with COPD. These effects are associated with an increased efficacy of the respiratory muscles and participation of the ABD compartment. PMID:27822031

Five months of physical exercise in hemodialysis patients: effects on aerobic capacity, physical function and self-rated health.

PubMed

Molsted, Stig; Eidemak, Inge; Sorensen, Helle Tauby; Kristensen, Jens Halkjaer

2004-01-01

The number of chronic renal failure patients treated by hemodialysis (HD) is continuously increasing. Most patients have reduced physical capacity and have a high risk of cardiac and vascular diseases. The aim of this study was to determine the effects of 5 months physical exercise of HD patients' physical capacity, self-rated health and risk factors for cardiovascular disease. 33 HD patients were included in the study. HD for more than 3 months, age >18 years. Diabetes mellitus, symptomatic cardiovascular disease, musculoskeletal limitations, severe peripheral polyneuropathy, inability to speak Danish or English, dementia or other mental disorders. The patients were randomly assigned to an exercise group (EG, n = 22) or a control group (CG, n = 11). Prior to randomization, baseline testing was performed. The effects were measured by aerobic capacity, '2-min stair climbing', 'squat test', self-rated health (SF36), blood pressure and lipids. All tests were carried out by blinded testers. The intervention consisted of 1 h of physical exercise twice a week for 5 months. 20 patients completed the intervention. Attendance was 74% of all sessions. There were no dropouts caused by complications related to the intervention. The EG had a significant increase in aerobic capacity, 'squat test' and Physical Function and Physical Component Scale (SF36). No significant changes were observed in any of the parameters in the CG. Physical exercise twice a week for 5 months increases physical function and aerobic capacity in HD patients. An exercise program with only two exercise sessions per week seems easy to implement in clinical practice with high attendance among participants. Further investigation is needed to determine the effects on blood pressure and lipids. There were no medical complications related to the exercise program. Copyright 2004 S. Karger AG, Basel

The use of aerobic exercise training in improving aerobic capacity in individuals with stroke: a meta-analysis

PubMed Central

Pang, Marco YC; Eng, Janice J; Dawson, Andrew S; Gylfadóttir, Sif

2011-01-01

Objective To determine whether aerobic exercise improves aerobic capacity in individuals with stroke. Design A systematic review of randomized controlled trials. Databases searched MEDLINE, CINAHL, EMBASE, Cochrane Database of Systematic Reviews, Physiotherapy Evidence Database were searched. Inclusion criteria Design: randomized controlled trials; Participants: individuals with stroke; Interventions: aerobic exercise training aimed at improving aerobic capacity; Outcomes Primary outcomes: aerobic capacity [peak oxygen consumption (VO2), peak workload); Secondary outcomes: walking velocity, walking endurance. Data Analysis The methodological quality was assessed by the PEDro scale. Meta-analyses were performed for all primary and secondary outcomes. Results Nine articles (seven RCTs) were identified. The exercise intensity ranged from 50% to 80% heart rate reserve. Exercise duration was 20–40 minutes for 3–5 days a week. The total number of subjects included in the studies was 480. All studies reported positive effects on aerobic capacity, regardless of the stage of stroke recovery. Meta-analysis revealed a significant homogeneous standardized effect size (SES) in favour of aerobic exercise to improve peak VO2 (SES, 0.42; 95%CI, 0.15 to 0.69; p=0.001) and peak workload (SES, 0.50; 95%CI, 0.26 to 0.73; p<0.001). There was also a significant homogeneous SES in favour of aerobic training to improve walking velocity (SES, 0.26; 95%CI, 0.05 to 0.48; p=0.008) and walking endurance (SES, 0.30; 95%CI, 0.06to 0.55; p=0.008). Conclusions There is good evidence that aerobic exercise is beneficial for improving aerobic capacity in people with mild and moderate stroke. Aerobic exercise should be an important component of stroke rehabilitation. PMID:16541930

Exercise science: research to sustain and enhance performance

NASA Astrophysics Data System (ADS)

Wingo, Jonathan E.

2013-05-01

Cardiovascular adjustments accompanying exercise in high ambient temperatures are likely responsible for diminished aerobic capacity and performance in such conditions. These adjustments include a phenomenon known as cardiovascular drift in which heart rate rises and stroke volume declines progressively over time during constant-rate exercise. A variety of factors modulate the magnitude of cardiovascular drift, e.g., elevated core and skin temperatures, dehydration, and exercise intensity. Regardless of the mode of manipulation, decreases in stroke volume associated with cardiovascular drift result in directionally and proportionally similar decreases in maximal aerobic capacity. Maximal aerobic capacity is determined by maximal heart rate, maximal tissue oxygen extraction, and maximal stroke volume. Because maximal heart rate and maximal tissue oxygen extraction are unaffected during exercise in the heat, decreased stroke volume associated with cardiovascular drift likely persists during maximal efforts and explains the decrease in maximal aerobic capacity. Decreased maximal aerobic capacity results in a greater perceptual and physiological strain accompanying any given level of work. Therefore, sustaining and enhancing performance involves sophisticated monitoring of physiological strain combined with development of countermeasures that mitigate the magnitude of deleterious phenomena like cardiovascular drift.

Cardiopulmonary Exercise Testing in Patients Following Massive and Submassive Pulmonary Embolism.

PubMed

Albaghdadi, Mazen S; Dudzinski, David M; Giordano, Nicholas; Kabrhel, Christopher; Ghoshhajra, Brian; Jaff, Michael R; Weinberg, Ido; Baggish, Aaron

2018-03-03

Little data exist regarding the functional capacity of patients following acute pulmonary embolism. We sought to characterize the natural history of symptom burden, right ventricular (RV) structure and function, and exercise capacity among survivors of massive and submassive pulmonary embolism. Survivors of submassive or massive pulmonary embolism (n=20, age 57±13.3 years, 8/20 female) underwent clinical evaluation, transthoracic echocardiography, and cardiopulmonary exercise testing at 1 and 6 months following hospital discharge. At 1 month, 9/20 (45%) patients had New York Heart Association II or greater symptoms, 13/20 (65%) demonstrated either persistent RV dilation or systolic dysfunction, and 14/20 (70%) had objective exercise impairment as defined by a peak oxygen consumption (V˙O 2 ) of <80% of age-sex predicted maximal values (16.25 [13.4-20.98] mL/kg per minute). At 6 months, no appreciable improvements in symptom severity, RV structure or function, and peak V˙O 2 (17.45 [14.08-22.48] mL/kg per minute, P =NS) were observed. No patients demonstrated an exercise limitation attributable to either RV/pulmonary vascular coupling, as defined by a VE/VCO 2 slope >33, or a pulmonary mechanical limit to exercise at either time point. Similarly, persistent RV dilation or dysfunction was not significantly related to symptom burden or peak V˙O 2 at either time point. Persistent symptoms, abnormalities of RV structure and function, and objective exercise limitation are common among survivors of massive and submassive pulmonary embolism. Functional impairment appears to be attributable to general deconditioning rather than intrinsic cardiopulmonary limitation, suggesting an important role for prescribed exercise rehabilitation as a means toward improved patient outcomes and quality of life. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Effects of tiotropium on lung hyperinflation, dyspnoea and exercise tolerance in COPD.

PubMed

O'Donnell, D E; Flüge, T; Gerken, F; Hamilton, A; Webb, K; Aguilaniu, B; Make, B; Magnussen, H

2004-06-01

The aim of this study was to test the hypothesis that use of tiotropium, a new long-acting anticholinergic bronchodilator, would be associated with sustained reduction in lung hyperinflation and, thereby, would improve exertional dyspnoea and exercise performance in patients with chronic obstructive pulmonary disease. A randomised, double-blind, placebo-controlled, parallel-group study was conducted in 187 patients (forced expiratory volume in one second 44 +/- 13% pred): 96 patients received 18 microg tiotropium and 91 patients received placebo once daily for 42 days. Spirometry, plethysmographic lung volumes, cycle exercise endurance and exertional dyspnoea intensity at 75% of each patient's maximal work capacity were compared. On day 42, the use of tiotropium was associated with the following effects at pre-dose and post-dose measurements as compared to placebo: vital capacity and inspiratory capacity (IC) increased, with inverse decreases in residual volume and functional residual capacity. Tiotropium increased post-dose exercise endurance time by 105 +/- 40 s (21%) as compared to placebo on day 42. At a standardised time near end-exercise (isotime), IC, tidal volume and minute ventilation all increased, whilst dyspnoea decreased by 0.9 +/- 0.3 Borg scale units. In conclusion, the use of tiotropium was associated with sustained reductions of lung hyperinflation at rest and during exercise. Resultant increases in inspiratory capacity permitted greater expansion of tidal volume and contributed to improvements in both exertional dyspnoea and exercise endurance.

Diagnostic value of the six-minute walk test (6MWT) in grown-up congenital heart disease (GUCH): Comparison with clinical status and functional exercise capacity.

PubMed

Kehmeier, Eva S; Sommer, Margot H; Galonska, Anika; Zeus, Tobias; Verde, Pablo; Kelm, Malte

2016-01-15

Exercise testing for the assessment of functional capacity plays an important role in long-term follow-up of GUCH patients. CPX is the favored modality for decision-making recommended in the current guidelines. In contrast to this complex method, the 6 MWT is a simple, easy-to-perform, safe, and commonly available exercise test. Although well-established in various cardiopulmonary diseases, the diagnostic impact of the 6 MWT in GUCH patients is not known so far. 102 GUCH patients were evaluated by 6 MWT and CPX simultaneously. Clinical symptoms were assessed, according to the NYHA classification. Additionally, an echocardiography study, and selected cardiac blood tests (N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitive Troponin T) were performed. Ranges of six-minute walk distance (6 MWD) and peak oxygen consumption (peakVO2) were 116-765 m and 6.4-36.2 ml/kg/min, respectively. 6 MWD and peakVO2 showed a close correlation (r=0.72, 95% CI, 0.63 to 0.79). Patients with a peakVO2 of ≤ 15.5 ml/kg/min were excellently identified by 6 MWT (c-value=0.82). A cut-off value of 482 m was optimal to predict reduced peakVO2. In multivariate regression analysis, 6 MWD and NYHA class were identified as relevant predictors of peakVO2. In subgroup analysis, Eisenmenger patients achieved the shortest 6 MWD (280, SD 178 m). In our study population of GUCH patients, the 6 MWD shows a close correlation to peakVO2, and an excellent prediction of reduced peakVO2. Thus, it seems to be an easy-to-perform and reliable screening parameter to evaluate functional capacity of these patients (Controlled Clinical Trials number, NCT02193243). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Effect of exhaustive weightlifting exercise on EMG, biochemical markers of muscle damage and performance capacity in young male subjects].

PubMed

Minigalin, A D; Shumakov, A R; Novozhilov, A V; Samsonova, A V; Kos'mina, E A; Kalinskiĭ, M I; Baranova, T I; Kubasov, I V; Morozov, V I

2015-01-01

The aim of this study was to examine the effect of exhaustive weightlifting exercise on electrical and biochemical variables and performance capacity in young male subjects. The onset of exercise (80-50% 1RM) was associated with a decrease in the amount of work performed, which was followed by a steady performance capacity at 40-10% 1RM. There were no significant changes of m. rectus femoris EMG maximal amplitude though it tended to be increased during the first half of exercise. A significant blood lactate concentration increase indicated that an anaerobic metabolism was a predominant mechanism of muscle contraction energy-supply. CK level in blood plasma did not change but plasma myoglobin concentration doubled immediately post-exercise. The data presented here suggest that decrease in performance capacity was likely due to progressive "refusal of work" of the fast motor units and work prolongation of weaker, intermediate and slow motor units. Unchangeable CK activity and relatively small increase in myoglobin concentration in plasma suggest that used weightlifting exercise did not induced substantial damage in myocytes' membranes in our subjects.

Effects of rehydration and food consumption on salivary flow, pH and buffering capacity in young adult volunteers during ergometer exercise.

PubMed

Tanabe, Mai; Takahashi, Toshiyuki; Shimoyama, Kazuhiro; Toyoshima, Yukako; Ueno, Toshiaki

2013-10-28

The aim of this study was to investigate the influences of rehydration and food consumption on salivary flow, pH, and buffering capacity during bicycle ergometer exercise in participants. Ten healthy volunteers exercised on a bicycle ergometer at 80% of their maximal heart rate. These sessions lasted for two periods of 20 min separated by 5-min rest intervals. Volunteers were subjected to one of the following conditions: (1) no water (mineral water) or food consumption, (2) only water for rehydration, (3) water and food consumption, (4) a sports drink only for rehydration, and (5) rehydration with a sports drink and food. Statistical significance was assessed using one-way analysis of variance and Dunnett's test (p < 0.05). The salivary pH decreased significantly during and after exercise in conditions 4 and 5. The salivary buffering capacity decreased significantly during exercise and/or after the exercise in conditions 1, 3, 4, and 5. The results showed that salivary pH and buffering capacity decreased greatly depending on the combination of a sports drink and food.

Does Aerobic Exercise Influence Intrinsic Brain Activity? An Aerobic Exercise Intervention among Healthy Old Adults

PubMed Central

Flodin, Pär; Jonasson, Lars S.; Riklund, Katrin; Nyberg, Lars; Boraxbekk, C. J.

2017-01-01

Previous studies have indicated that aerobic exercise could reduce age related decline in cognition and brain functioning. Here we investigated the effects of aerobic exercise on intrinsic brain activity. Sixty sedentary healthy males and females (64–78 years) were randomized into either an aerobic exercise group or an active control group. Both groups recieved supervised training, 3 days a week for 6 months. Multimodal brain imaging data was acquired before and after the intervention, including 10 min of resting state brain functional magnetic resonance imaging (rs-fMRI) and arterial spin labeling (ASL). Additionally, a comprehensive battery of cognitive tasks assessing, e.g., executive function and episodic memory was administered. Both the aerobic and the control group improved in aerobic capacity (VO2-peak) over 6 months, but a significant group by time interaction confirmed that the aerobic group improved more. Contrary to our hypothesis, we did not observe any significant group by time interactions with regard to any measure of intrinsic activity. To further probe putative relationships between fitness and brain activity, we performed post hoc analyses disregarding group belongings. At baseline, VO2-peak was negativly related to BOLD-signal fluctuations (BOLDSTD) in mid temporal areas. Over 6 months, improvements in aerobic capacity were associated with decreased connectivity between left hippocampus and contralateral precentral gyrus, and positively to connectivity between right mid-temporal areas and frontal and parietal regions. Independent component analysis identified a VO2-related increase in coupling between the default mode network and left orbitofrontal cortex, as well as a decreased connectivity between the sensorimotor network and thalamus. Extensive exploratory data analyses of global efficiency, connectome wide multivariate pattern analysis (connectome-MVPA), as well as ASL, did not reveal any relationships between aerobic fitness and intrinsic brain activity. Moreover, fitness-predicted changes in functional connectivity did not relate to changes in cognition, which is likely due to absent cross-sectional or longitudinal relationships between VO2-peak and cognition. We conclude that the aerobic exercise intervention had limited influence on patterns of intrinsic brain activity, although post hoc analyses indicated that individual changes in aerobic capacity preferentially influenced mid-temporal brain areas. PMID:28848424

Does Aerobic Exercise Influence Intrinsic Brain Activity? An Aerobic Exercise Intervention among Healthy Old Adults.

PubMed

Flodin, Pär; Jonasson, Lars S; Riklund, Katrin; Nyberg, Lars; Boraxbekk, C J

2017-01-01

Previous studies have indicated that aerobic exercise could reduce age related decline in cognition and brain functioning. Here we investigated the effects of aerobic exercise on intrinsic brain activity. Sixty sedentary healthy males and females (64-78 years) were randomized into either an aerobic exercise group or an active control group. Both groups recieved supervised training, 3 days a week for 6 months. Multimodal brain imaging data was acquired before and after the intervention, including 10 min of resting state brain functional magnetic resonance imaging (rs-fMRI) and arterial spin labeling (ASL). Additionally, a comprehensive battery of cognitive tasks assessing, e.g., executive function and episodic memory was administered. Both the aerobic and the control group improved in aerobic capacity (VO 2 -peak) over 6 months, but a significant group by time interaction confirmed that the aerobic group improved more. Contrary to our hypothesis, we did not observe any significant group by time interactions with regard to any measure of intrinsic activity. To further probe putative relationships between fitness and brain activity, we performed post hoc analyses disregarding group belongings. At baseline, VO 2 -peak was negativly related to BOLD-signal fluctuations (BOLD STD ) in mid temporal areas. Over 6 months, improvements in aerobic capacity were associated with decreased connectivity between left hippocampus and contralateral precentral gyrus, and positively to connectivity between right mid-temporal areas and frontal and parietal regions. Independent component analysis identified a VO 2 -related increase in coupling between the default mode network and left orbitofrontal cortex, as well as a decreased connectivity between the sensorimotor network and thalamus. Extensive exploratory data analyses of global efficiency, connectome wide multivariate pattern analysis (connectome-MVPA), as well as ASL, did not reveal any relationships between aerobic fitness and intrinsic brain activity. Moreover, fitness-predicted changes in functional connectivity did not relate to changes in cognition, which is likely due to absent cross-sectional or longitudinal relationships between VO 2 -peak and cognition. We conclude that the aerobic exercise intervention had limited influence on patterns of intrinsic brain activity, although post hoc analyses indicated that individual changes in aerobic capacity preferentially influenced mid-temporal brain areas.

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise.

PubMed

Tedjasaputra, Vincent; van Diepen, Sean; Collins, Sophie É; Michaelchuk, Wade M; Stickland, Michael K

2017-02-20

Exercise is a stress to the pulmonary vasculature. With incremental exercise, the pulmonary diffusing capacity (DLCO) must increase to meet the increased oxygen demand; otherwise, a diffusion limitation may occur. The increase in DLCO with exercise is due to increased capillary blood volume (Vc) and membrane diffusing capacity (Dm). Vc and Dm increase secondary to the recruitment and distension of pulmonary capillaries, increasing the surface area for gas exchange and decreasing pulmonary vascular resistance, thereby attenuating the increase in pulmonary arterial pressure. At the same time, the recruitment of intrapulmonary arteriovenous anastomoses (IPAVA) during exercise may contribute to gas exchange impairment and/or prevent large increases in pulmonary artery pressure. We describe two techniques to evaluate pulmonary diffusion and circulation at rest and during exercise. The first technique uses multiple-fraction of inspired oxygen (FIO2) DLCO breath holds to determine Vc and Dm at rest and during exercise. Additionally, echocardiography with intravenous agitated saline contrast is used to assess IPAVAs recruitment. Representative data showed that the DLCO, Vc, and Dm increased with exercise intensity. Echocardiographic data showed no IPAVA recruitment at rest, while contrast bubbles were seen in the left ventricle with exercise, suggesting exercise-induced IPAVA recruitment. The evaluation of pulmonary capillary blood volume, membrane diffusing capacity, and IPAVA recruitment using echocardiographic methods is useful to characterize the ability of the lung vasculature to adapt to the stress of exercise in health as well as in diseased groups, such as those with pulmonary arterial hypertension and chronic obstructive pulmonary disease.

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise

PubMed Central

Tedjasaputra, Vincent; van Diepen, Sean; Collins, Sophie É; Michaelchuk, Wade M.; Stickland, Michael K.

2017-01-01

Exercise is a stress to the pulmonary vasculature. With incremental exercise, the pulmonary diffusing capacity (DLCO) must increase to meet the increased oxygen demand; otherwise, a diffusion limitation may occur. The increase in DLCO with exercise is due to increased capillary blood volume (Vc) and membrane diffusing capacity (Dm). Vc and Dm increase secondary to the recruitment and distension of pulmonary capillaries, increasing the surface area for gas exchange and decreasing pulmonary vascular resistance, thereby attenuating the increase in pulmonary arterial pressure. At the same time, the recruitment of intrapulmonary arteriovenous anastomoses (IPAVA) during exercise may contribute to gas exchange impairment and/or prevent large increases in pulmonary artery pressure. We describe two techniques to evaluate pulmonary diffusion and circulation at rest and during exercise. The first technique uses multiple-fraction of inspired oxygen (FIO2) DLCO breath holds to determine Vc and Dm at rest and during exercise. Additionally, echocardiography with intravenous agitated saline contrast is used to assess IPAVAs recruitment. Representative data showed that the DLCO, Vc, and Dm increased with exercise intensity. Echocardiographic data showed no IPAVA recruitment at rest, while contrast bubbles were seen in the left ventricle with exercise, suggesting exercise-induced IPAVA recruitment. The evaluation of pulmonary capillary blood volume, membrane diffusing capacity, and IPAVA recruitment using echocardiographic methods is useful to characterize the ability of the lung vasculature to adapt to the stress of exercise in health as well as in diseased groups, such as those with pulmonary arterial hypertension and chronic obstructive pulmonary disease. PMID:28287506

Expiratory flow limitation and operating lung volumes during exercise in older and younger adults.

PubMed

Smith, Joshua R; Kurti, Stephanie P; Meskimen, Kayla; Harms, Craig A

2017-06-01

We determined the effect of aging on expiratory flow limitation (EFL) and operating lung volumes when matched for lung size. We hypothesized that older adults will exhibit greater EFL and increases in EELV during exercise compared to younger controls. Ten older (5M/5W; >60years old) and nineteen height-matched young adults (10M/9W) were recruited. Young adults were matched for%predicted forced vital capacity (FVC) (Y-matched%Pred FVC; n=10) and absolute FVC (Y-matched FVC; n=10). Tidal flow-volume loops were recorded during the incremental exercise test with maximal flow-volume loops measured pre- and post-exercise. Compared to younger controls, older adults exhibited more EFL at ventilations of 26, 35, 51, and 80L/min. The older group had higher end-inspiratory lung volume compared to Y-matched%Pred FVC group during submaximal ventilations. The older group increased EELV during exercise, while EELV stayed below resting in the Y-matched%Pred FVC group. These data suggest older adults exhibit more EFL and increase EELV earlier during exercise compared to younger adults. Copyright © 2017 Elsevier B.V. All rights reserved.

The role of postural control in the association between aerobic capacity and walking capacity in chronic stroke: a cross-sectional analysis.

PubMed

Outermans, Jacqueline C; van de Port, Ingrid; Kwakkel, Gert; Visser-Meily, Johanna M; Wittink, Harriet

2018-03-12

Reports on the association between aerobic capacity and walking capacity in people after stroke show disparate results. To determine (1) if the predictive validity of peak oxygen uptake (VO2peak) for walking capacity post stroke is different from that of maximal oxygen uptake (VO2max) and (2) if postural control, hemiplegic lower extremity muscle strength, age and gender distort the association between aerobic capacity and walking capacity. Cross-sectional study. General community in Utrecht, the Netherlands. Community-dwelling people more than three months after stroke. Measurement of aerobic capacity were performed with cardiopulmonary exercise testing (CPET) and differentiated between the achievement of VO2peak or VO2max. Measurement of walking capacity with the Six Minute Walk Test (6MWT), postural control with the Performance Oriented Mobility Assessment (POMA) and hemiplegic lower extremity muscle strength with the Motricity Index (MI-LE). Fifty-one out of 62 eligible participants, aged 64.7 (±12.5) years were included. Analysis of covariance (ANCOVA) showed a nonsignificant difference between the predictive validities of VO2max (N = 22, β = 0.56; 95%CI 0.12 - 0.97) and VO2peak (N = 29, β = 0.72; 95%CI 0.38 - 0.92). Multiple regression analysis of the pooled sample showed a significant decrease in the β value of VO2peak (21.6%) for the 6MWT when adding the POMA as a covariate in the association model. VO2peak remained significantly related to 6MWT after correcting for the POMA (β = 0.56 (95%CI 0.39 - 0.75)) CONCLUSIONS: The results suggest similar predictive validity of aerobic capacity for walking capacity in participants achieving VO2max compared to those only achieving VO2peak. Postural control confounds the association between aerobic capacity and walking capacity. Aerobic capacity remains a valid predictor of walking capacity. Aerobic capacity is an important factor associated with walking capacity after stroke. However, to understand this relationship, postural control needs to be measured. Both aerobic capacity and postural control may need to be addressed during interventions aiming to improve walking capacity after stroke.

The influence of training characteristics on the effect of exercise training in patients with coronary artery disease: Systematic review and meta-regression analysis.

PubMed

Kraal, Jos J; Vromen, Tom; Spee, Ruud; Kemps, Hareld M C; Peek, Niels

2017-10-15

Although exercise-based cardiac rehabilitation improves exercise capacity of coronary artery disease patients, it is unclear which training characteristic determines this improvement. Total energy expenditure and its constituent training characteristics (training intensity, session frequency, session duration and programme length) vary considerably among clinical trials, making it hard to compare studies directly. Therefore, we performed a systematic review and meta-regression analysis to assess the effect of total energy expenditure and its constituent training characteristics on exercise capacity. We identified randomised controlled trials comparing continuous aerobic exercise training with usual care for patients with coronary artery disease. Studies were included when training intensity, session frequency, session duration and programme length was described, and exercise capacity was reported in peakVO 2 . Energy expenditure was calculated from the four training characteristics. The effect of training characteristics on exercise capacity was determined using mixed effects linear regression analyses. The analyses were performed with and without total energy expenditure as covariate. Twenty studies were included in the analyses. The mean difference in peakVO 2 between the intervention group and control group was 3.97ml·min -1 ·kg -1 (p<0.01, 95% CI 2.86 to 5.07). Total energy expenditure was significantly related to improvement of exercise capacity (effect size 0.91ml·min -1 ·kg -1 per 100J·kg, p<0.01, 95% CI 0.77 to 1.06), no effect was found for its constituent training characteristics after adjustment for total energy expenditure. We conclude that the design of an exercise programme should primarily be aimed at optimising total energy expenditure rather than on one specific training characteristic. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Relationship Between Post-exercise Heart Rate Recovery and Changing Ratio of Cardiopulmonary Exercise Capacity.

PubMed

Kim, Ji-Hyun; Choe, Yu-Ri; Song, Min-Keun; Choi, In-Sung; Han, Jae-Young

2017-12-01

To determine whether heart rate recovery (HRR) following an exercise tolerance test (ETT) is correlated with a changing ratio of peak oxygen consumption (VO 2 ) and maximal metabolic equivalents (MET max ). A total of 60 acute myocardial infarction (AMI) patients who underwent ETT at both assessment points - 3 weeks (T0) after the AMI attack and 3 months after T0 (T1) were included. After achieving a peak workload, the treadmill was stopped with a 5-minute cooldown period, and the patients recovered in a comfortable and relaxed seated position. HRR was defined as the difference between the maximal heart rate (HR max ) and the HR measured at specific time intervals - immediately after the cool down period (HRR-0) and 3 minutes after the completion of the ETT (HRR-3). HRR-0 and HRR-3 increased over time, whereas VO 2max and MET max did not show significant changes. There was a positive correlation between HRR at T0 and the exercise capacity at T0. HRR at T0 also showed a positive correlation with the exercise capacity at T1. There was no significant correlation between HRR measured at T0 and the change in the ratio of VO 2max and MET max , as calculated by subtracting VO 2max and MET max obtained at T0 from those obtained at T1, divided by VO 2max at T0 and multiplied by 100. Post-exercise HRR measured at 3 weeks after the AMI onset can reflect the exercise capacity 3 months after the first ETT. However, it may be difficult to correlate post-exercise HRR at T0 with the degree of increase in cardiopulmonary exercise capacity in patients with AMI.

Effects of dynamic hyperinflation on exercise capacity and quality of life in stable COPD patients.

PubMed

Zhao, Li; Peng, Liyue; Wu, Baomei; Bu, Xiaoning; Wang, Chen

2016-09-01

Dynamic hyperinflation (DH) is an important pathophysiological characteristic of chronic obstructive pulmonary disease (COPD). There is increasing evidence that DH has negative effects on exercise performance and quality of life. The objective of this study was to explore effects of DH on exercise capacity and quality of life in stable COPD patients. Fifty-eight COPD patients and 20 matched healthy individuals underwent pulmonary function test, 6-min walk test and symptom-limited cardiopulmonary exercise test (CPET). End-expiratory lung volume/total lung capacity ratio (EELVmax/TLC) at peak exercise of CPET was evaluated, and EELVmax/TLC ≥ 75% was defined as 'severe dynamic hyperinflation (SDH)'. Of the 58 patients studied, 29 (50.0%) presented with SDH (SDH+ group, EELVmax/TLC 79.60 ± 3.60%), having worse maximal exercise capacity reflected by lower peakload, maximal oxygen uptake (VO2 max), maximal carbon dioxide output (VCO2 max) and maximal minute ventilation (VEmax) than did those without SDH (SDH- group, EELVmax/TLC 67.44 ± 6.53%). The EELVmax/TLC ratio at peak exercise had no association with variables of pulmonary function and 6-min walk distance (6MWD), but correlated inversely with peakload, VO2 max, VCO2 max and VEmax (r = -0.300~-0.351, P < 0.05). Although no significant differences were observed, patients with EELVmax/TLC ≥ 75% tended to have higher COPD assessment test score (15.07 ± 6.55 vs 13.28 ± 6.59, P = 0.303). DH develops variably during exercise and has a greater impact on maximal exercise capacity than 6MWD, even in those with the same extent of pulmonary function impairment at rest. © 2015 John Wiley & Sons Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbott, Robert G.; Forsythe, James C.

Adaptive Thinking has been defined here as the capacity to recognize when a course of action that may have previously been effective is no longer effective and there is need to adjust strategy. Research was undertaken with human test subjects to identify the factors that contribute to adaptive thinking. It was discovered that those most effective in settings that call for adaptive thinking tend to possess a superior capacity to quickly and effectively generate possible courses of action, as measured using the Category Generation test. Software developed for this research has been applied to develop capabilities enabling analysts to identifymore » crucial factors that are predictive of outcomes in fore-on-force simulation exercises.« less

Supervised exercise improves cutaneous reinnervation capacity in metabolic syndrome patients.

PubMed

Singleton, J Robinson; Marcus, Robin L; Lessard, Margaret K; Jackson, Justin E; Smith, A Gordon

2015-01-01

Unmyelinated cutaneous axons are vulnerable to physical and metabolic injury, but also capable of rapid regeneration. This balance may help determine risk for peripheral neuropathy associated with diabetes or metabolic syndrome. Capsaicin application for 48 hours induces cutaneous fibers to die back into the dermis. Regrowth can be monitored by serial skin biopsies to determine intraepidermal nerve fiber density (IENFD). We used this capsaicin axotomy technique to examine the effects of exercise on cutaneous regenerative capacity in the setting of metabolic syndrome. Baseline ankle IENFD and 30-day cutaneous regeneration after thigh capsaicin axotomy were compared for participants with type 2 diabetes (n = 35) or metabolic syndrome (n = 32) without symptoms or examination evidence of neuropathy. Thirty-six participants (17 with metabolic syndrome) then joined twice weekly observed exercise and lifestyle counseling. Axotomy regeneration was repeated in month 4 during this intervention. Baseline distal leg IENFD was significantly reduced for both metabolic syndrome and diabetic groups. With exercise, participants significantly improved exercise capacity and lower extremity power. Following exercise, 30-day reinnervation rate improved (0.051 ± 0.027 fibers/mm/day before vs 0.072 ± 0.030 after exercise, p = 0.002). Those who achieved improvement in more metabolic syndrome features experienced a greater degree of 30-day reinnervation (p < 0.012). Metabolic syndrome was associated with reduced baseline IENFD and cutaneous regeneration capacity comparable to that seen in diabetes. Exercise-induced improvement in metabolic syndrome features increased cutaneous regenerative capacity. The results underscore the potential benefit to peripheral nerve function of a behavioral modification approach to metabolic improvement. © 2014 American Neurological Association.

Breathing exercises with vagal biofeedback may benefit patients with functional dyspepsia.

PubMed

Hjelland, Ina E; Svebak, Sven; Berstad, Arnold; Flatabø, Geir; Hausken, Trygve

2007-09-01

Many patients with functional dyspepsia (FD) have postprandial symptoms, impaired gastric accommodation and low vagal tone. The aim of this study was to improve vagal tone, and thereby also drinking capacity, intragastric volume and quality of life, using breathing exercises with vagal biofeedback. Forty FD patients were randomized to either a biofeedback group or a control group. The patients received similar information and care. Patients in the biofeedback group were trained in breathing exercises, 6 breaths/min, 5 min each day for 4 weeks, using specially designed software for vagal biofeedback. Effect variables included maximal drinking capacity using a drink test (Toro clear meat soup 100 ml/min), intragastric volume at maximal drinking capacity, respiratory sinus arrhythmia (RSA), skin conductance (SC) and dyspepsia-related quality of life scores. Drinking capacity and quality of life improved significantly more in the biofeedback group than in the control group (p=0.02 and p=0.01) without any significant change in baseline autonomic activity (RSA and SC) or intragastric volume. After the treatment period, RSA during breathing exercises was significantly correlated to drinking capacity (r=0.6, p=0.008). Breathing exercises with vagal biofeedback increased drinking capacity and improved quality of life in FD patients, but did not improve baseline vagal tone.

Effects of high-intensity interval training on central haemodynamics and skeletal muscle oxygenation during exercise in patients with chronic heart failure.

PubMed

Spee, Ruud F; Niemeijer, Victor M; Wijn, Pieter F; Doevendans, Pieter A; Kemps, Hareld M

2016-12-01

Background High-intensity interval training (HIT) improves exercise capacity in patients with chronic heart failure (CHF). Moreover, HIT was associated with improved resting cardiac function. However, the extent to which these improvements actually contribute to training-induced changes in exercise capacity remains to be elucidated. Therefore, we evaluated the effects of HIT on exercising central haemodynamics and skeletal muscle oxygenation. Methods Twenty-six CHF patients were randomised to a 12-week 4 × 4 minute HIT program at 85-95% of peak VO 2 or usual care. Patients performed maximal and submaximal cardiopulmonary exercise testing with simultaneous assessment of cardiac output and skeletal muscle oxygenation by near infrared spectroscopy, using the amplitude of the tissue saturation index (TSIamp). Results Peak workload increased by 11% after HIT ( p between group = 0.01) with a non-significant increase in peak VO 2 (+7%, p between group = 0.19). Cardiac reserve increased by 37% after HIT ( p within group = 0.03, p between group = 0.08); this increase was not related to improvements in peak workload. Oxygen uptake recovery kinetics after submaximal exercise were accelerated by 20% ( p between group = 0.02); this improvement was related to a decrease in TSIamp ( r = 0.71, p = 0.03), but not to changes in cardiac output kinetics. Conclusion HIT induced improvements in maximal exercise capacity and exercising haemodynamics at peak exercise. Improvements in recovery after submaximal exercise were associated with attenuated skeletal muscle deoxygenation during submaximal exercise, but not with changes in cardiac output kinetics, suggesting that the effect of HIT on submaximal exercise capacity is mediated by improved microvascular oxygen delivery-to-utilisation matching.

Predictors of mortality in patients with emphysema and severe airflow obstruction.

PubMed

Martinez, Fernando J; Foster, Gregory; Curtis, Jeffrey L; Criner, Gerard; Weinmann, Gail; Fishman, Alfred; DeCamp, Malcolm M; Benditt, Joshua; Sciurba, Frank; Make, Barry; Mohsenifar, Zab; Diaz, Philip; Hoffman, Eric; Wise, Robert

2006-06-15

Limited data exist describing risk factors for mortality in patients having predominantly emphysema. A total of 609 patients with severe emphysema (ages 40-83 yr; 64.2% male) randomized to the medical therapy arm of the National Emphysema Treatment Trial formed the study group. Cox proportional hazards regression analysis was used to investigate risk factors for all-cause mortality. Risk factors examined included demographics, body mass index, physiologic data, quality of life, dyspnea, oxygen utilization, hemoglobin, smoking history, quantitative emphysema markers on computed tomography, and a modification of a recently described multifunctional index (modified BODE). Overall, high mortality was seen in this cohort (12.7 deaths per 100 person-years; 292 total deaths). In multivariate analyses, increasing age (p=0.001), oxygen utilization (p=0.04), lower total lung capacity % predicted (p=0.05), higher residual volume % predicted (p=0.04), lower maximal cardiopulmonary exercise testing workload (p=0.002), greater proportion of emphysema in the lower lung zone versus the upper lung zone (p=0.005), and lower upper-to-lower-lung perfusion ratio (p=0.007), and modified BODE (p=0.02) were predictive of mortality. FEV1 was a significant predictor of mortality in univariate analysis (p=0.005), but not in multivariate analysis (p=0.21). Although patients with advanced emphysema experience significant mortality, subgroups based on age, oxygen utilization, physiologic measures, exercise capacity, and emphysema distribution identify those at increased risk of death.

Breathing pattern and chest wall volumes during exercise in patients with cystic fibrosis, pulmonary fibrosis and COPD before and after lung transplantation.

PubMed

Wilkens, H; Weingard, B; Lo Mauro, A; Schena, E; Pedotti, A; Sybrecht, G W; Aliverti, A

2010-09-01

Pulmonary fibrosis (PF), cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) often cause chronic respiratory failure (CRF). In order to investigate if there are different patterns of adaptation of the ventilatory pump in CRF, in three groups of lung transplant candidates with PF (n=9, forced expiratory volume in 1 s (FEV(1))=37+/-3% predicted, forced vital capacity (FVC)=32+/-2% predicted), CF (n=9, FEV(1)=22+/-3% predicted, FVC=30+/-3% predicted) and COPD (n=21, FEV(1)=21+/-1% predicted, FVC=46+/-2% predicted), 10 healthy controls and 16 transplanted patients, total and compartmental chest wall volumes were measured by opto-electronic plethysmography during rest and exercise. Three different breathing patterns were found during CRF in PF, CF and COPD. Patients with COPD were characterised by a reduced duty cycle at rest and maximal exercise (34+/-1%, p<0.001), while patients with PF and CF showed an increased breathing frequency (49+/-6 and 34+/-2/min, respectively) and decreased tidal volume (0.75+/-0.10 and 0.79+/-0.07 litres) (p<0.05). During exercise, end-expiratory chest wall and rib cage volumes increased significantly in patients with COPD and CF but not in those with PF. End-inspiratory volumes did not increase in CF and PF. The breathing pattern of transplanted patients was similar to that of healthy controls. There are three distinct patterns of CRF in patients with PF, CF and COPD adopted by the ventilatory pump to cope with the underlying lung disease that may explain why patients with PF and CF are prone to respiratory failure earlier than patients with COPD. After lung transplantation the chronic adaptations of the ventilatory pattern to advanced lung diseases are reversible and indicate that the main contributing factor is the lung itself rather than systemic effects of the disease.

Effects of Detraining on Anthropometry, Aerobic Capacity and Functional Ability in Adults with Down Syndrome

ERIC Educational Resources Information Center

Boer, P. H.

2018-01-01

Background: Structured exercise has shown to improve parameters of functional fitness in adults with Down syndrome (DS). However, few, if any, continue to exercise after exercise intervention studies. Consequently, the purpose of this study was to determine the effects of detraining on anthropometry, aerobic capacity and functional ability of…

Association Between Exercise Capacity and Late Onset of Dementia, Alzheimer Disease, and Cognitive Impairment.

PubMed

Müller, Jan; Chan, Khin; Myers, Jonathan N

2017-02-01

To address the association between exercise capacity and the onset of dementia, Alzheimer disease, and cognitive impairment. For 6104 consecutive veteran patients (mean ± SD age: 59.2±11.4 years) referred for treadmill exercise testing, the combined end point of dementia, Alzheimer disease, and cognitive impairment was abstracted from the Veterans Affairs computerized patient record system. After mean ± SD follow-up of 10.3±5.5 years, 353 patients (5.8%) developed the composite end point at a mean ± SD age of 76.7±10.3 years. After correction for confounders in multivariate Cox proportional hazards regression, higher age at exercise testing (hazard ratio [HR]=1.08; 95% CI, 1.07-1.09; P<.001), current smoking (HR=1.44; 95% CI, 1.08-1.93; P=.01), and exercise capacity (HR=0.92; 95% CI, 0.89-0.96; P<.001) emerged as predictors of cognitive impairment. Each 1-metabolic equivalent increase in exercise capacity conferred a nearly 8% reduction in the incidence of cognitive impairment. Meeting the recommendations for daily activity was not associated with a delay in onset of cognitive impairment (HR=1.07; 95% CI, 0.86-1.32; P=.55). Exercise capacity is strongly associated with cognitive function; the inverse association between fitness and cognitive impairment provides an additional impetus for health care providers to promote physical activity. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Exercise starts and ends in the brain.

PubMed

Kayser, Bengt

2003-10-01

Classically the limit to endurance of exercise is explained in terms of metabolic capacity. Cardio-respiratory capacity and muscle fatigue are thought to set the limit and the majority of studies on factors limiting endurance exercise discuss issues such as maximal oxygen uptake (VO2max), aerobic enzyme capacity, cardiac output, glycogen stores, etc. However, this paradigm does not explain the limitation to endurance exercise with large muscle groups at altitude, when at exhaustion exercise is ended without limb locomotor muscle fatigue and with sub-maximal cardiac output. A simple fact provides a basis for an explanation. Voluntary exercise starts and ends in the brain. It starts with spatial and temporal recruitment of motor units and ends with their de-recruitment. A conscious decision precedes a voluntary effort. The end of effort is again volitional and a forced conscious decision to stop precedes it, but it is unknown what forces the off-switch of recruitment at exhaustion although sensation of exertion certainly plays a role. An alternative model explaining the limitation of exercise endurance thus proposes that the central nervous system integrates input from various sources all related to the exercise and limits the intensity and duration of recruitment of limb skeletal muscle to prevent jeopardizing the integrity of the organism. This model acknowledges the cardio-respiratory and muscle metabolic capacities as prime actors on the performance scene, while crediting the central nervous system for its pivotal role as the ultimate site where exercise starts and ends.

Body mass index, exercise capacity, and mortality risk in male veterans with hypertension.

PubMed

Faselis, Charles; Doumas, Michael; Panagiotakos, Demosthenes; Kheirbek, Raya; Korshak, Lauren; Manolis, Athanasios; Pittaras, Andreas; Tsioufis, Costas; Papademetriou, Vasilios; Fletcher, Ross; Kokkinos, Peter

2012-04-01

Overweight and obesity are associated with increased risk of chronic diseases and mortality. Exercise capacity is inversely associated with mortality risk. However, little is known on the interaction between fitness, fatness, and mortality risk in hypertensive individuals. Thus, we assessed the interaction between exercise capacity, fatness, and all-cause mortality in hypertensive males. A graded exercise test was performed in 4,183 hypertensive veterans (mean age ± s.d.; 63.3 ± 10.5 years) at the Veterans Affairs Medical Center, Washington, DC. We defined three body weight categories based on body mass index (BMI): normal weight (BMI <25); overweight (BMI 25-29.9); and obese (BMI ≥30); and three fitness categories based on peak metabolic equivalents (METs) achieved: low-fit (≤5 METs); moderate-fit (5.1-7.5 MET); and high-fit (>7.5 METs). During a median follow-up period of 7.2 years, there were 1,000 deaths. The association between exercise capacity and mortality risk was strong, inverse, and graded. For each 1-MET increase in exercise capacity the adjusted risk was 20% for normal weight, 12% for overweight, and 25% for obese (P < 0.001). When compared to normal weight but unfit individuals, mortality risks were 60% lower in the overweight/high-fit and 78% lower in the obese/high-fit individuals (P < 0.001). Increased exercise capacity is associated with lower mortality risk in hypertensive males regardless of BMI. The risk for overweight and obese but fit individuals was significantly lower when compared to normal weight but unfit. These findings suggest that in older hypertensive men, it may be healthier to be fit regardless of standard BMI category than unfit and normal weight.

The effects of in-flight treadmill exercise on postflight orthostatic tolerance

NASA Technical Reports Server (NTRS)

Siconolfi, Steven F.; Charles, John B.

1992-01-01

In-flight aerobic exercise is thought to decrease the deconditioning effects of microgravity. Two deconditioning characteristics are the decreases in aerobic capacity (maximum O2 uptake) and an increased cardiovascular response to orthostatic stress (supine to standing). Changes in both parameters were examined after Shuttle flights of 8 to 11 days in astronauts who performed no in-flight exercise, a lower than normal volume of exercise, and a near-normal volume of exercise. The exercise regimen was a traditional continuous protocol. Maximum O2 uptake was maintained in astronauts who completed a near-normal exercise volume of in-flight exercise. Cardiovascular responses to stand test were equivocal among the groups. The use of the traditional exercise regimen as a means to maintain adequate orthostatic responses produced equivocal responses. A different exercise prescription may be more effective in maintaining both exercise capacity and orthostatic tolerance.

Exercise training modalities in chronic heart failure: does high intensity aerobic interval training make the difference?

PubMed

Giallauria, Francesco; Smart, Neil Andrew; Cittadini, Antonio; Vigorito, Carlo

2016-10-14

Exercise training (ET) is strongly recommended in patients with chronic heart failure (CHF). Moderate-intensity aerobic continuous ET is the best established training modality in CHF patients. In the last decade, however, high-intensity interval exercise training (HIIT) has aroused considerable interest in cardiac rehabilitation community. Basically, HIIT consists of repeated bouts of high-intensity exercise alternated with recovery periods. In CHF patients, HIIT exerts larger improvements in exercise capacity compared to moderate-continuous ET. These results are intriguing, mostly considering that better functional capacity translates into an improvement of symptoms and quality of life. Notably, HIIT did not reveal major safety issues; although CHF patients should be clinically stable, have had recent exposure to at least regular moderate-intensity exercise, and appropriate supervision and monitoring during and after the exercise session are mandatory. The impact of HIIT on cardiac dimensions and function and on endothelial function remains uncertain. HIIT should not replace other training modalities in heart failure but should rather complement them. Combining and tailoring different ET modalities according to each patient's baseline clinical characteristics (i.e. exercise capacity, personal needs, preferences and goals) seem the most astute approach to exercise prescription.

Combined short-arm centrifuge and aerobic exercise training improves cardiovascular function and physical working capacity in humans.

PubMed

Yang, Chang-Bin; Zhang, Shu; Zhang, Yu; Wang, Bing; Yao, Yong-Jie; Wang, Yong-Chun; Wu, Yan-Hong; Liang, Wen-Bin; Sun, Xi-Qing

2010-12-01

Musculoskeletal and cardiovascular deconditioning occurring in long-term spaceflight gives rise to the needs to develop new strategies to counteract these adverse effects. Short-arm centrifuge combined with ergometer has been proposed as a strategy to counteract adverse effects of microgravity. This study sought to investigate whether the combination of short-arm centrifuge and aerobic exercise training have advantages over short-arm centrifuge or aerobic exercise training alone. One week training was conducted by 24 healthy men. They were randomly divided into 3 groups: (1) short-arm centrifuge training, (2) aerobic exercise training, 40 W, and (3) combined short-arm centrifuge and aerobic exercise training. Before and after training, the cardiac pump function represented by stroke volume, cardiac output, left ventricular ejection time, and total peripheral resistance was evaluated. Variability of heart rate and systolic blood pressure were determined by spectral analysis. Physical working capacity was surveyed by near maximal physical working capacity test. The 1-week combined short-arm centrifuge and aerobic exercise training remarkably ameliorated the cardiac pump function and enhanced vasomotor sympathetic nerve modulation and improved physical working capacity by 10.9% (P<.05, n=8). In contrast, neither the short-arm centrifuge nor the aerobic exercise group showed improvements in these functions. These results demonstrate that combined short-arm centrifuge and aerobic exercise training has advantages over short-arm centrifuge or aerobic exercise training alone in influencing several physiologically important cardiovascular functions in humans. The combination of short-arm centrifuge and aerobic exercise offers a promising countermeasure to microgravity.

Exercise training improves characteristics of exercise oscillatory ventilation in chronic heart failure.

PubMed

Panagopoulou, Niki; Karatzanos, Eleftherios; Dimopoulos, Stavros; Tasoulis, Athanasios; Tachliabouris, Ioannis; Vakrou, Styliani; Sideris, Antonios; Gratziou, Christina; Nanas, Serafim

2017-05-01

Background Exercise oscillatory ventilation in chronic heart failure has been suggested as a factor related to adverse cardiac events, aggravated prognosis and higher mortality. Exercise training is well known to affect exercise capacity and mechanisms of pathophysiology beneficially in chronic heart failure. Little is known, however, about the exercise training effects on characteristics of exercise oscillatory ventilation in chronic heart failure patients. Design and methods Twenty (out of 38) stable chronic heart failure patients exhibited exercise oscillatory ventilation (age 54 ± 11 years, peak oxygen uptake 15.0 ± 5.0 ml/kg per minute). Patients attended 36 sessions of high intensity interval exercise. All patients underwent cardiopulmonary exercise testing before and after the programme. Assessment of exercise oscillatory ventilation was based on the amplitude of cyclic fluctuations in breathing during rest and exercise. All values are mean ± SD. Results Exercise training reduced ( P < 0.05) the percentage of exercise oscillatory ventilation duration (79.0 ± 13.0 to 50.0 ± 25.0%), while average amplitude (5.2 ± 2.0 to 4.9 ± 1.6 L/minute) and length (44.0 ± 10.9 to 41.0 ± 6.7 seconds) did not change ( P > 0.05). Exercise oscillatory ventilation patients also increased exercise capacity ( P < 0.05). Conclusions A rehabilitation programme based on high intensity interval training improved exercise oscillatory ventilation observed in chronic heart failure patients, as well as cardiopulmonary efficiency and functional capacity.

Physical activity and maximal oxygen uptake in adults with Prader-Willi syndrome.

PubMed

Gross, Itai; Hirsch, Harry J; Constantini, Naama; Nice, Shachar; Pollak, Yehuda; Genstil, Larry; Eldar-Geva, Talia; Tsur, Varda Gross

2017-03-16

Prader-Willi Syndrome (PWS) is the most common genetic syndrome causing life-threatening obesity. Strict adherence to a low-calorie diet and regular physical activity are needed to prevent weight gain. Direct measurement of maximal oxygen uptake (VO 2 max), the "gold standard" for assessing aerobic exercise capacity, has not been previously described in PWS. Assess aerobic capacity by direct measurement of VO 2 max in adults with PWS, and in age and BMI-matched controls (OC), and compare the results with values obtained by indirect prediction methods. Seventeen individuals (12 males) age: 19-35 (28.6 ± 4.9) years, BMI: 19.4-38.1 (27.8 ± 5) kg/m 2 with genetically confirmed PWS who exercise daily, and 32 matched OC (22 males) age: 19-36 (29.3 ± 5.2) years, BMI: 21.1-48.1 (26.3 ± 4.9) kg/m 2 . All completed a medical questionnaire and performed strength and flexibility tests. VO 2 max was determined by measuring oxygen consumption during a graded exercise test on a treadmill. VO 2 max (24.6 ± 3.4 vs 46.5 ± 12.2 ml/kg/min, p < 0.001) and ventilatory threshold (20 ± 2 and 36.2 ± 10.5 ml/kg/min, p < 0.001), maximal strength of both hands (36 ± 4 vs 91.4 ± 21.2 kg, p < 0.001), and flexibility (15.2 ± 9.5 vs 26 ± 11.1 cm, p = 0.001) were all significantly lower for PWS compared to OC. Predicted estimates and direct measurements of VO 2 max were almost identical for the OC group (p = 0.995), for the PWS group, both methods for estimating VO 2 max gave values which were significantly greater (p < 0.001) than results obtained by direct measurements. Aerobic capacity, assessed by direct measurement of VO 2 max, is significantly lower in PWS adults, even in those who exercise daily, compared to OCs. Indirect estimates of VO 2 max are accurate for OC, but unreliable in PWS. Direct measurement of VO 2 should be used for designing personal training programs and in clinical studies of exercise in PWS.

The effects of water-based exercise in combination with blood flow restriction on strength and functional capacity in post-menopausal women.

PubMed

Araújo, Joamira P; Neto, Gabriel R; Loenneke, Jeremy P; Bemben, Michael G; Laurentino, Gilberto C; Batista, Gilmário; Silva, Júlio C G; Freitas, Eduardo D S; Sousa, Maria S C

2015-12-01

Water-based exercise and low-intensity exercise in combination with blood flow restriction (BFR) are two methods that have independently been shown to improve muscle strength in those of advancing age. The objective of this study was to assess the long-term effect of water-based exercise in combination with BFR on maximum dynamic strength and functional capacity in post-menopausal women. Twenty-eight women underwent an 8-week water-based exercise program. The participants were randomly allocated to one of the three groups: (a) water exercise only, (b) water exercise + BFR, or (c) a non-exercise control group. Functional capacity (chair stand test, timed up and go test, gait speed, and dynamic balance) and strength testing were tested before and after the 8-week aquatic exercise program. The main findings were as follows: (1) water-based exercise in combination with BFR significantly increased the lower limb maximum strength which was not observed with water-based exercise alone and (2) water-based exercise, regardless of the application of BFR, increased functional performance measured by the timed up and go test over a control group. Although we used a healthy population in the current study, these findings may have important implications for those who may be contraindicated to using traditional resistance exercise. Future research should explore this promising modality in these clinical populations.

Work, exercise, and space flight. 2: Modification of adaptation by exercise (exercise prescription)

NASA Technical Reports Server (NTRS)

Thornton, William

1989-01-01

The fundamentals of exercise theory on earth must be rigorously understood and applied to prevent adaptation to long periods of weightlessness. Locomotor activity, not weight, determines the capacity or condition of the largest muscles and bones in the body and usually also determines cardio-respiratory capacity. Absence of this activity results in rapid atrophy of muscle, bone, and cardio-respiratory capacity. Upper body muscle and bone are less affected depending upon the individual's usual, or 1-g, activities. Methodology is available to prevent these changes but space operations demand that it be done in the most efficient fashion, i.e., shortest time. At this point in time we can reasonably select the type of exercise and methods of obtaining it, but additional work in 1-g will be required to optimize the time.

Effects of rehydration and food consumption on salivary flow, pH and buffering capacity in young adult volunteers during ergometer exercise

PubMed Central

2013-01-01

Background The aim of this study was to investigate the influences of rehydration and food consumption on salivary flow, pH, and buffering capacity during bicycle ergometer exercise in participants. Methods Ten healthy volunteers exercised on a bicycle ergometer at 80% of their maximal heart rate. These sessions lasted for two periods of 20 min separated by 5-min rest intervals. Volunteers were subjected to one of the following conditions: (1) no water (mineral water) or food consumption, (2) only water for rehydration, (3) water and food consumption, (4) a sports drink only for rehydration, and (5) rehydration with a sports drink and food. Statistical significance was assessed using one-way analysis of variance and Dunnett’s test (p < 0.05). Results The salivary pH decreased significantly during and after exercise in conditions 4 and 5. The salivary buffering capacity decreased significantly during exercise and/or after the exercise in conditions 1, 3, 4, and 5. Conclusions The results showed that salivary pH and buffering capacity decreased greatly depending on the combination of a sports drink and food. PMID:24160307

Influence of acute exercise of varying intensity and duration on postprandial oxidative stress.

PubMed

Canale, Robert E; Farney, Tyler M; McCarthy, Cameron G; Bloomer, Richard J

2014-09-01

Aerobic exercise can reduce postprandial lipemia, and possibly oxidative stress, when performed prior to a lipid-rich meal. To compare the impact of acute exercise on postprandial oxidative stress. We compared aerobic and anaerobic exercise bouts of different intensities and durations on postprandial blood triglycerides (TAG), oxidative stress biomarkers (malondialdehyde, hydrogen peroxide, advanced oxidation protein products), and antioxidant status (trolox equivalent antioxidant capacity, superoxide dismutase, catalase, glutathione peroxidase). Twelve trained men (21-35 years) underwent four conditions: (1) No exercise rest; (2) 60-min aerobic exercise at 70% heart rate reserve; (3) five 60-s sprints at 100% max capacity; and (4) ten 15-s sprints at 200% max capacity. All exercise bouts were performed on a cycle ergometer. A high-fat meal was consumed 1 h after exercise cessation. Blood samples were collected pre-meal and 2 and 4 h post-meal and analyzed for TAG, oxidative stress biomarkers, and antioxidant status. No significant interaction or condition effects were noted for any variable (p > 0.05), with acute exercise having little to no effect on the magnitude of postprandial oxidative stress. In a sample of healthy, well-trained men, neither aerobic nor anaerobic exercise attenuates postprandial oxidative stress in response to a high-fat meal.

Feedback-controlled robotics-assisted treadmill exercise to assess and influence aerobic capacity early after stroke: a proof-of-concept study.

PubMed

Stoller, Oliver; Schindelholz, Matthias; Bichsel, Lukas; Schuster, Corina; de Bie, Rob A; de Bruin, Eling D; Hunt, Kenneth J

2014-07-01

The majority of post-stroke individuals suffer from low exercise capacity as a secondary reaction to immobility. The aim of this study was to prove the concept of feedback-controlled robotics-assisted treadmill exercise (RATE) to assess aerobic capacity and guide cardiovascular exercise in severely impaired individuals early after stroke. Subjects underwent constant load and incremental exercise testing using a human-in-the-loop feedback system within a robotics-assisted exoskeleton (Lokomat, Hocoma AG, CH). Inclusion criteria were: stroke onset ≤8 weeks, stable medical condition, non-ambulatory status, moderate motor control of the lower limbs and appropriate cognitive function. Outcome measures included oxygen uptake kinetics, peak oxygen uptake (VO2peak), gas exchange threshold (GET), peak heart rate (HRpeak), peak work rate (Ppeak) and accuracy of reaching target work rate (P-RMSE). Three subjects (18-42 d post-stroke) were included. Oxygen uptake kinetics during constant load ranged from 42.0 to 60.2 s. Incremental exercise testing showed: VO2peak range 19.7-28.8 ml/min/kg, GET range 11.6-12.7 ml/min/kg, and HRpeak range 115-161 bpm. Ppeak range was 55.2-110.9 W and P-RMSE range was 3.8-7.5 W. The concept of feedback-controlled RATE for assessment of aerobic capacity and guidance of cardiovascular exercise is feasible. Further research is warranted to validate the method on a larger scale. Aerobic capacity is seriously reduced in post-stroke individuals as a secondary reaction to immobility. Robotics-assisted walking devices may have substantial clinical relevance regarding assessment and improvement of aerobic capacity early after stroke. Feedback-controlled robotics-assisted treadmill exercise represents a new concept for cardiovascular assessment and intervention protocols for severely impaired individuals.

Long-term follow-up of patients receiving lung-volume-reduction surgery versus medical therapy for severe emphysema by the National Emphysema Treatment Trial Research Group.

PubMed

Naunheim, Keith S; Wood, Douglas E; Mohsenifar, Zab; Sternberg, Alice L; Criner, Gerard J; DeCamp, Malcolm M; Deschamps, Claude C; Martinez, Fernando J; Sciurba, Frank C; Tonascia, James; Fishman, Alfred P

2006-08-01

The National Emphysema Treatment Trial defined subgroups of patients with severe emphysema in whom lung-volume-reduction surgery (LVRS) improved survival and function at 2 years. Two additional years of follow-up provide valuable information regarding durability. A total of 1218 patients with severe emphysema were randomized to receive LVRS or medical treatment. We present updated analyses (4.3 versus 2.4 years median follow-up), including 40% more patients with functional measures 2 years after randomization. The intention-to-treat analysis of 1218 randomized patients demonstrates an overall survival advantage for LVRS, with a 5-year risk ratio (RR) for death of 0.86 (p = 0.02). Improvement was more likely in the LVRS than in the medical group for maximal exercise through 3 years and for health-related quality of life (St. George's Respiratory Questionnaire [SGRQ]) through 4 years. Updated comparisons of survival and functional improvement were consistent with initial results for four clinical subgroups of non-high-risk patients defined by upper-lobe predominance and exercise capacity. After LVRS, the upper-lobe patients with low exercise capacity demonstrated improved survival (5-year RR, 0.67; p = 0.003), exercise throughout 3 years (p < 0.001), and symptoms (SGRQ) through 5 years (p < 0.001 years 1 to 3, p = 0.01 year 5). Upper-lobe-predominant and high-exercise-capacity LVRS patients obtained no survival advantage but were likely to improve exercise capacity (p < 0.01 years 1 to 3) and SGRQ (p < 0.01 years 1 to 4). Effects of LVRS are durable, and it can be recommended for upper-lobe-predominant emphysema patients with low exercise capacity and should be considered for palliation in patients with upper-lobe emphysema and high exercise capacity.

Resistance training and mitochondrial metabolism

USDA-ARS?s Scientific Manuscript database

Objective: To determine if resistance exercise training improves skeletal muscle substrate oxidative capacity in older adults. Background: A decline in skeletal muscle oxidative capacity occurs with aging. Aerobic exercise increases skeletal muscle’s ability to oxidize multiple substrates. Th...

Effect of metformin on exercise capacity in metabolic syndrome.

PubMed

Paul, Abi Albon; Dkhar, Steven Aibor; Kamalanathan, Sadishkumar; Thabah, Molly Mary; George, Melvin; Chandrasekaran, Indumathi; Gunaseelan, Vikneswaran; Selvarajan, Sandhiya

2017-11-01

Metabolic syndrome is a constellation of risk factors with increased predilection towards occurrence of cardiovascular diseases. Currently physical exercise and management with metformin are the prevailing treatment modalities for metabolic syndrome. Patients with metabolic syndrome have been found to have reduced exercise capacity over a period of time. Likewise metformin has been shown to decrease exercise capacity among healthy volunteers. Hence this study aims to evaluate the effect of metformin on the exercise capacity of patients with metabolic syndrome. Prospective study with 6 weeks follow up. Newly diagnosed patients with metabolic syndrome and to be started on Table Metformin 500mg twice a day were recruited for the study after obtaining written informed consent. Cardiopulmonary Exercise Testing (CPET) was done at baseline before the subjects were started on metformin and after 6 weeks of treatment using cardiopulmonary exercise testing apparatus (ZAN600). Fifteen treatment naïve patients with metabolic syndrome completed six weeks of therapy with metformin. In these patients oxygen uptake [VO2] showed statistically significant decrease from 1.10±0.44 at baseline to 0.9±0.39 (l/min) after six weeks of treatment with metformin [mean difference of -0.20 (-0.31 to -0.09); P=0.001]. Similarly oxygen uptake/kg body weight [VO2/Kg] showed a significant decrease from 14.10±4.73 to 11.44±3.81 (mlkg -1 min -1 ) at the end of six weeks of treatment [mean difference of -2.66 (-4.06 to -1.26); P=0.001]. Six weeks of treatment with metformin significantly decreases exercise capacity in newly diagnosed patients with metabolic syndrome. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Statins are related to impaired exercise capacity in males but not females.

PubMed

Bahls, Martin; Groß, Stefan; Ittermann, Till; Busch, Raila; Gläser, Sven; Ewert, Ralf; Völzke, Henry; Felix, Stephan B; Dörr, Marcus

2017-01-01

Exercise and statins reduce cardiovascular disease (CVD). Exercise capacity may be assessed using cardiopulmonary exercise testing (CPET). Whether statin medication is associated with CPET parameters is unclear. We investigated if statins are related with exercise capacity during CPET in the general population. Cross-sectional data of two independent cohorts of the Study of Health in Pomerania (SHIP) were merged (n = 3,500; 50% males). Oxygen consumption (VO2) at peak exercise (VO2peak) and anaerobic threshold (VO2@AT) was assessed during symptom-limited CPET. Two linear regression models related VO2peak with statin usage were calculated. Model 1 adjusted for age, sex, previous myocardial infarction, and physical inactivity and model 2 additionally for body mass index, smoking, hypertension, diabetes and estimated glomerular filtration rate. Propensity score matching was used for validation. Statin usage was associated with lower VO2peak (no statin: 2336; 95%-confidence interval [CI]: 2287-2,385 vs. statin 2090; 95%-CI: 2,031-2149 ml/min; P < .0001) and VO2@AT (no statin: 1,172; 95%-CI: 1,142-1,202 vs. statin: 1,111; 95%-CI: 1,075-1,147 ml/min; P = .0061) in males but not females (VO2peak: no statin: 1,467; 95%-CI: 1,417-1,517 vs. statin: 1,503; 95%-CI: 1,426-1,579 ml/min; P = 1.00 and VO2@AT: no statin: 854; 95%-CI: 824-885 vs. statin 864; 95%-CI: 817-911 ml/min; P = 1.00). Model 2 revealed similar results. Propensity scores analysis confirmed the results. In the general population present statin medication was related with impaired exercise capacity in males but not females. Sex specific effects of statins on cardiopulmonary exercise capacity deserve further research.

Fine mapping of a QTL on chromosome 13 for submaximal exercise capacity training response: the HERITAGE Family Study.

PubMed

Rice, Treva K; Sarzynski, Mark A; Sung, Yun Ju; Argyropoulos, George; Stütz, Adrian M; Teran-Garcia, Margarita; Rao, D C; Bouchard, Claude; Rankinen, Tuomo

2012-08-01

Although regular exercise improves submaximal aerobic capacity, there is large variability in its response to exercise training. While this variation is thought to be partly due to genetic differences, relatively little is known about the causal genes. Submaximal aerobic capacity traits in the current report include the responses of oxygen consumption (ΔVO(2)60), power output (ΔWORK60), and cardiac output (ΔQ60) at 60% of VO2max to a standardized 20-week endurance exercise training program. Genome-wide linkage analysis in 475 HERITAGE Family Study Caucasians identified a locus on chromosome 13q for ΔVO(2)60 (LOD = 3.11). Follow-up fine mapping involved a dense marker panel of over 1,800 single-nucleotide polymorphisms (SNPs) in a 7.9-Mb region (21.1-29.1 Mb from p-terminus). Single-SNP analyses found 14 SNPs moderately associated with both ΔVO(2)60 at P ≤ 0.005 and the correlated traits of ΔWORK60 and ΔQ60 at P < 0.05. Haplotype analyses provided several strong signals (P < 1.0 × 10(-5)) for ΔVO(2)60. Overall, association analyses narrowed the target region and included potential biological candidate genes (MIPEP and SGCG). Consistent with maximal heritability estimates of 23%, up to 20% of the phenotypic variance in ΔVO(2)60 was accounted for by these SNPs. These results implicate candidate genes on chromosome 13q12 for the ability to improve submaximal exercise capacity in response to regular exercise. Submaximal exercise at 60% of maximal capacity is an exercise intensity that falls well within the range recommended in the Physical Activity Guidelines for Americans and thus has potential public health relevance.

Fine mapping of a QTL on chromosome 13 for submaximal exercise capacity training response: the HERITAGE Family Study

PubMed Central

Rice, Treva K.; Sarzynski, Mark A.; Sung, Yun Ju; Argyropoulos, George; Stütz, Adrian M.; Teran-Garcia, Margarita; Rao, D. C.; Bouchard, Claude

2014-01-01

Although regular exercise improves submaximal aerobic capacity, there is large variability in its response to exercise training. While this variation is thought to be partly due to genetic differences, relatively little is known about the causal genes. Submaximal aerobic capacity traits in the current report include the responses of oxygen consumption (ΔVO260), power output (ΔWORK60), and cardiac output (ΔQ60) at 60% of VO2max to a standardized 20-week endurance exercise training program. Genome-wide linkage analysis in 475 HERITAGE Family Study Caucasians identified a locus on chromosome 13q for ΔVO260 (LOD = 3.11). Follow-up fine mapping involved a dense marker panel of over 1,800 single-nucleotide polymorphisms (SNPs) in a 7.9-Mb region (21.1–29.1 Mb from p-terminus). Single-SNP analyses found 14 SNPs moderately associated with both ΔVO260 at P ≤ 0.005 and the correlated traits of ΔWORK60 and ΔQ60 at P < 0.05. Haplotype analyses provided several strong signals (P<1.0 × 10−5) for ΔVO260. Overall, association analyses narrowed the target region and included potential biological candidate genes (MIPEP and SGCG). Consistent with maximal heritability estimates of 23%, up to 20% of the phenotypic variance in ΔVO260 was accounted for by these SNPs. These results implicate candidate genes on chromosome 13q12 for the ability to improve submaximal exercise capacity in response to regular exercise. Submaximal exercise at 60% of maximal capacity is an exercise intensity that falls well within the range recommended in the Physical Activity Guidelines for Americans and thus has potential public health relevance. PMID:22170014

Using implicit attitudes of exercise importance to predict explicit exercise dependence symptoms and exercise behaviors.

PubMed

Forrest, Lauren N; Smith, April R; Fussner, Lauren M; Dodd, Dorian R; Clerkin, Elise M

2016-01-01

"Fast" (i.e., implicit) processing is relatively automatic; "slow" (i.e., explicit) processing is relatively controlled and can override automatic processing. These different processing types often produce different responses that uniquely predict behaviors. In the present study, we tested if explicit, self-reported symptoms of exercise dependence and an implicit association of exercise as important predicted exercise behaviors and change in problematic exercise attitudes. We assessed implicit attitudes of exercise importance and self-reported symptoms of exercise dependence at Time 1. Participants reported daily exercise behaviors for approximately one month, and then completed a Time 2 assessment of self-reported exercise dependence symptoms. Undergraduate males and females (Time 1, N = 93; Time 2, N = 74) tracked daily exercise behaviors for one month and completed an Implicit Association Test assessing implicit exercise importance and subscales of the Exercise Dependence Questionnaire (EDQ) assessing exercise dependence symptoms. Implicit attitudes of exercise importance and Time 1 EDQ scores predicted Time 2 EDQ scores. Further, implicit exercise importance and Time 1 EDQ scores predicted daily exercise intensity while Time 1 EDQ scores predicted the amount of days exercised. Implicit and explicit processing appear to uniquely predict exercise behaviors and attitudes. Given that different implicit and explicit processes may drive certain exercise factors (e.g., intensity and frequency, respectively), these behaviors may contribute to different aspects of exercise dependence.

Using implicit attitudes of exercise importance to predict explicit exercise dependence symptoms and exercise behaviors

PubMed Central

Forrest, Lauren N.; Smith, April R.; Fussner, Lauren M.; Dodd, Dorian R.; Clerkin, Elise M.

2015-01-01

Objectives ”Fast” (i.e., implicit) processing is relatively automatic; “slow” (i.e., explicit) processing is relatively controlled and can override automatic processing. These different processing types often produce different responses that uniquely predict behaviors. In the present study, we tested if explicit, self-reported symptoms of exercise dependence and an implicit association of exercise as important predicted exercise behaviors and change in problematic exercise attitudes. Design We assessed implicit attitudes of exercise importance and self-reported symptoms of exercise dependence at Time 1. Participants reported daily exercise behaviors for approximately one month, and then completed a Time 2 assessment of self-reported exercise dependence symptoms. Method Undergraduate males and females (Time 1, N = 93; Time 2, N = 74) tracked daily exercise behaviors for one month and completed an Implicit Association Test assessing implicit exercise importance and subscales of the Exercise Dependence Questionnaire (EDQ) assessing exercise dependence symptoms. Results Implicit attitudes of exercise importance and Time 1 EDQ scores predicted Time 2 EDQ scores. Further, implicit exercise importance and Time 1 EDQ scores predicted daily exercise intensity while Time 1 EDQ scores predicted the amount of days exercised. Conclusion Implicit and explicit processing appear to uniquely predict exercise behaviors and attitudes. Given that different implicit and explicit processes may drive certain exercise factors (e.g., intensity and frequency, respectively), these behaviors may contribute to different aspects of exercise dependence. PMID:26195916

Exercise therapy for functional capacity in chronic diseases: an overview of meta-analyses of randomised controlled trials.

PubMed

Pasanen, Tero; Tolvanen, Samppa; Heinonen, Ari; Kujala, Urho M

2017-10-01

To summarise all meta-analyses of randomised controlled trials that have evaluated the effects of exercise therapy on functional capacity in patients with chronic diseases. Umbrella review of meta-analyses of randomised controlled trials. We systematically searched the CENTRAL, CINAHL, DARE, Medline, OTSeeker, PEDro, SPORTDiscus, ProQuest Nursing & Allied Health Database, Web of Science, Scopus, OpenGrey and BMC Proceedings from database inception to 1 September 2016. We included meta-analyses that compared the effects of exercise therapy with no treatment or usual care in adults with non-communicable chronic diseases and included outcomes related to functional capacity. We excluded meta-analyses with less than 100 patients. Eighty-five meta-analyses with 22 different chronic diseases were included. The exercise interventions resulted in statistically significant (p<0.05) improvements for 126 of 146 (86%) functional capacity outcomes, compared with the control group. The standardised mean differences were small in 64 (44%), moderate in 54 (37%) and large in 28 (19%) of the 146 functional capacity outcomes. The results were similar for aerobic exercise, resistance training, and aerobic and resistance training combined. There were no significant differences in serious adverse effects between the intervention and control groups in any of the meta-analyses. Exercise therapy appears to be a safe way to improve functional capacity and reduce disability in individuals with chronic disease. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Angiotensin II receptor blocker improves the lowered exercise capacity and impaired mitochondrial function of the skeletal muscle in type 2 diabetic mice.

PubMed

Takada, Shingo; Kinugawa, Shintaro; Hirabayashi, Kagami; Suga, Tadashi; Yokota, Takashi; Takahashi, Masashige; Fukushima, Arata; Homma, Tsuneaki; Ono, Taisuke; Sobirin, Mochamad A; Masaki, Yoshihiro; Mizushima, Wataru; Kadoguchi, Tomoyasu; Okita, Koichi; Tsutsui, Hiroyuki

2013-04-01

NAD(P)H oxidase-induced oxidative stress is at least in part involved with lowered exercise capacity and impaired mitochondrial function in high-fat diet (HFD)-induced diabetic mice. NAD(P)H oxidase can be activated by activation of the renin-angiotensin system. We investigated whether ANG II receptor blocker can improve exercise capacity in diabetic mice. C57BL/6J mice were fed a normal diet (ND) or HFD, and each group of mice was divided into two groups: treatment with or without olmesartan (OLM; 3 mg·kg(-1)·day(-1) in the drinking water). The following groups of mice were studied: ND, ND+OLM, HFD, and HFD+OLM (n = 10 for each group). After 8 wk, HFD significantly increased body weight, plasma glucose, and insulin compared with ND, and OLM did not affect these parameters in either group. Exercise capacity, as determined by treadmill tests, was significantly reduced in HFD, and this reduction was ameliorated in HFD+OLM. ADP-dependent mitochondrial respiration was significantly decreased, and NAD(P)H oxidase activity and superoxide production by lucigenin chemiluminescence were significantly increased in skeletal muscle from HFD, which were attenuated by OLM. There were no such effects by OLM in ND. We concluded that OLM ameliorated the decrease in exercise capacity in diabetic mice via improvement in mitochondrial function and attenuation of oxidative stress in skeletal muscle. These data may have a clinical impact on exercise capacity in the medical treatment of diabetes mellitus.

An 8-Week Ketogenic Low Carbohydrate, High Fat Diet Enhanced Exhaustive Exercise Capacity in Mice.

PubMed

Ma, Sihui; Huang, Qingyi; Yada, Koichi; Liu, Chunhong; Suzuki, Katsuhiko

2018-05-25

Current fueling tactics for endurance exercise encourage athletes to ingest a high carbohydrate diet. However, athletes are not generally encouraged to use fat, the largest energy reserve in the human body. A low carbohydrate, high fat ketogenic diet (KD) is a nutritional approach ensuring that the body utilizes lipids. Although KD has been associated with weight-loss, enhanced fat utilization in muscle and other beneficial effects, there is currently no clear proof whether it could lead to performance advantage. To evaluate the effects of KD on endurance exercise capacity, we studied the performance of mice subjected to a running model after consuming KD for eight weeks. Weight dropped dramatically in KD-feeding mice, even though they ate more calories. KD-feeding mice showed enhanced running time without aggravated muscle injury. Blood biochemistry and correlation analysis indicated the potential mechanism is likely to be a keto-adaptation enhanced capacity to transport and metabolize fat. KD also showed a potential preventive effect on organ injury caused by acute exercise, although KD failed to exert protection from muscle injury. Ultimately, KD may contribute to prolonged exercise capacity.

Lung function profiles and aerobic capacity of adult cigarette and hookah smokers after 12 weeks intermittent training.

PubMed

Koubaa, Abdessalem; Triki, Moez; Trabelsi, Hajer; Masmoudi, Liwa; Zeghal, Khaled N; Sahnoun, Zouhair; Hakim, Ahmed

2015-01-01

Introduction Pulmonary function is compromised in most smokers. Yet it is unknown whether exercise training improves pulmonary function and aerobic capacity in cigarette and hookah smokers and whether these smokers respond in a similar way as do non-smokers. Aim To evaluate the effects of an interval exercise training program on pulmonary function and aerobic capacity in cigarette and hookah smokers. Methods Twelve cigarette smokers, 10 hookah smokers, and 11 non-smokers participated in our exercise program. All subjects performed 30 min of interval exercise (2 min of work followed by 1 min of rest) three times a week for 12 weeks at an intensity estimated at 70% of the subject's maximum aerobic capacity ([Formula: see text]). Pulmonary function was measured using spirometry, and maximum aerobic capacity was assessed by maximal exercise testing on a treadmill before the beginning and at the end of the exercise training program. Results As expected, prior to the exercise intervention, the cigarette and hookah smokers had significantly lower pulmonary function than the non-smokers. The 12-week exercise training program did not significantly affect lung function as assessed by spirometry in the non-smoker group. However, it significantly increased both forced expiratory volume in 1 second and peak expiratory flow (PEF) in the cigarette smoker group, and PEF in the hookah smoker group. Our training program had its most notable impact on the cardiopulmonary system of smokers. In the non-smoker and cigarette smoker groups, the training program significantly improved [Formula: see text] (4.4 and 4.7%, respectively), v [Formula: see text] (6.7 and 5.6%, respectively), and the recovery index (7.9 and 10.5%, respectively). Conclusions After 12 weeks of interval training program, the increase of [Formula: see text] and the decrease of recovery index and resting heart rate in the smoking subjects indicated better exercise tolerance. Although the intermittent training program altered pulmonary function only partially, both aerobic capacity and life quality were improved. Intermittent training should be advised in the clinical setting for subjects with adverse health behaviors.

Lung function profiles and aerobic capacity of adult cigarette and hookah smokers after 12 weeks intermittent training.

PubMed

Koubaa, Abdessalem; Triki, Moez; Trabelsi, Hajer; Masmoudi, Liwa; Zeghal, Khaled N; Sahnoun, Zouhair; Hakim, Ahmed

2015-01-01

Pulmonary function is compromised in most smokers. Yet it is unknown whether exercise training improves pulmonary function and aerobic capacity in cigarette and hookah smokers and whether these smokers respond in a similar way as do non-smokers. To evaluate the effects of an interval exercise training program on pulmonary function and aerobic capacity in cigarette and hookah smokers. Twelve cigarette smokers, 10 hookah smokers, and 11 non-smokers participated in our exercise program. All subjects performed 30 min of interval exercise (2 min of work followed by 1 min of rest) three times a week for 12 weeks at an intensity estimated at 70% of the subject's maximum aerobic capacity (VO2max). Pulmonary function was measured using spirometry, and maximum aerobic capacity was assessed by maximal exercise testing on a treadmill before the beginning and at the end of the exercise training program. As expected, prior to the exercise intervention, the cigarette and hookah smokers had significantly lower pulmonary function than the non-smokers. The 12-week exercise training program did not significantly affect lung function as assessed by spirometry in the non-smoker group. However, it significantly increased both forced expiratory volume in 1 second and peak expiratory flow (PEF) in the cigarette smoker group, and PEF in the hookah smoker group. Our training program had its most notable impact on the cardiopulmonary system of smokers. In the non-smoker and cigarette smoker groups, the training program significantly improved VO2max (4.4 and 4.7%, respectively), v VO2max (6.7 and 5.6%, respectively), and the recovery index (7.9 and 10.5%, respectively). After 12 weeks of interval training program, the increase of VO2max and the decrease of recovery index and resting heart rate in the smoking subjects indicated better exercise tolerance. Although the intermittent training program altered pulmonary function only partially, both aerobic capacity and life quality were improved. Intermittent training should be advised in the clinical setting for subjects with adverse health behaviors.

Heart rate behavior during an exercise stress test in obese patients.

PubMed

Gondoni, L A; Titon, A M; Nibbio, F; Augello, G; Caetani, G; Liuzzi, A

2009-03-01

Heart rate (HR) response to exercise has not been fully described in the obese. We wanted to study the differences between obese and non-obese patients in HR behavior during an exercise stress test and to determine whether these differences influence exercise capacity. We studied 554 patients (318 females) who underwent a treadmill exercise test. All subjects were in sinus rhythm. Patients with ischemic heart disease, with reduced ejection fraction and patients taking drugs that interfere with HR were excluded. The population included 231 patients with BMI<30 kg/m(2) (group 1), 212 patients who were unfit and obese (group 2) and 111 patients who were trained obese (group 3). Resting HR was similar in the various groups. Peak HR, HR recovery and chronotropic index were lower in obese subjects, regardless of their fitness level. Multivariate analysis showed that HR related variables were associated with age, BMI, height, hypertension and various pharmacologic treatments, while exercise capacity was strongly dependent on HR behavior, as well as on sex, age, BMI and diabetes. Obese subjects have a marked impairment of HR behavior during exercise and in the recovery period, and the blunted increase in HR is the most important factor that influences exercise capacity.

A Cycle Ergometer Exercise Program Improves Exercise Capacity and Inspiratory Muscle Function in Hospitalized Patients Awaiting Heart Transplantation: a Pilot Study

PubMed Central

Forestieri, Patrícia; Guizilini, Solange; Peres, Monique; Bublitz, Caroline; Bolzan, Douglas W.; Rocco, Isadora S.; Santos, Vinícius B.; Moreira, Rita Simone L.; Breda, João R.; de Almeida, Dirceu R.; Carvalho, Antonio Carlos de C.; Arena, Ross; Gomes, Walter J.

2016-01-01

Objective The purpose of this study was to evaluate the effect of a cycle ergometer exercise program on exercise capacity and inspiratory muscle function in hospitalized patients with heart failure awaiting heart transplantation with intravenous inotropic support. Methods Patients awaiting heart transplantation were randomized and allocated prospectively into two groups: 1) Control Group (n=11) - conventional protocol; and 2) Intervention Group (n=7) - stationary cycle ergometer exercise training. Functional capacity was measured by the six-minute walk test and inspiratory muscle strength assessed by manovacuometry before and after the exercise protocols. Results Both groups demonstrated an increase in six-minute walk test distance after the experimental procedure compared to baseline; however, only the intervention group had a significant increase (P=0.08 and P=0.001 for the control and intervention groups, respectively). Intergroup comparison revealed a greater increase in the intervention group compared to the control (P<0.001). Regarding the inspiratory muscle strength evaluation, the intragroup analysis demonstrated increased strength after the protocols compared to baseline for both groups; statistical significance was only demonstrated for the intervention group, though (P=0.22 and P<0.01, respectively). Intergroup comparison showed a significant increase in the intervention group compared to the control (P<0.01). Conclusion Stationary cycle ergometer exercise training shows positive results on exercise capacity and inspiratory muscle strength in patients with heart failure awaiting cardiac transplantation while on intravenous inotropic support. PMID:27982348

Comparison of Watermelon and Carbohydrate Beverage on Exercise-Induced Alterations in Systemic Inflammation, Immune Dysfunction, and Plasma Antioxidant Capacity

PubMed Central

Shanely, R. Andrew; Nieman, David C.; Perkins-Veazie, Penelope; Henson, Dru A.; Meaney, Mary P.; Knab, Amy M.; Cialdell-Kam, Lynn

2016-01-01

Consuming carbohydrate- and antioxidant-rich fruits during exercise as a means of supporting and enhancing both performance and health is of interest to endurance athletes. Watermelon (WM) contains carbohydrate, lycopene, l-citrulline, and l-arginine. WM may support exercise performance, augment antioxidant capacity, and act as a countermeasure to exercise-induced inflammation and innate immune changes. Trained cyclists (n = 20, 48 ± 2 years) participated in a randomized, placebo controlled, crossover study. Subjects completed two 75 km cycling time trials after either 2 weeks ingestion of 980 mL/day WM puree or no treatment. Subjects drank either WM puree containing 0.2 gm/kg carbohydrate or a 6% carbohydrate beverage every 15 min during the time trials. Blood samples were taken pre-study and pre-, post-, 1 h post-exercise. WM ingestion versus no treatment for 2-weeks increased plasma l-citrulline and l-arginine concentrations (p < 0.0125). Exercise performance did not differ between WM puree or carbohydrate beverage trials (p > 0.05), however, the rating of perceived exertion was greater during the WM trial (p > 0.05). WM puree versus carbohydrate beverage resulted in a similar pattern of increase in blood glucose, and greater increases in post-exercise plasma antioxidant capacity, l-citrulline, l-arginine, and total nitrate (all p < 0.05), but without differences in systemic markers of inflammation or innate immune function. Daily WM puree consumption fully supported the energy demands of exercise, and increased post-exercise blood levels of WM nutritional components (l-citrulline and l-arginine), antioxidant capacity, and total nitrate, but without an influence on post-exercise inflammation and changes in innate immune function. PMID:27556488

Home-based versus center-based aerobic exercise on cardiopulmonary performance, physical function, quality of life and quality of sleep of overweight patients with chronic kidney disease.

PubMed

Aoike, Danilo Takashi; Baria, Flavia; Kamimura, Maria Ayako; Ammirati, Adriano; Cuppari, Lilian

2018-02-01

The association between chronic kidney disease (CKD) and obesity can decrease the patients' cardiopulmonary capacity, physical functioning and quality of life. The search for effective and practical alternative methods of exercise to engage patients in training programs is of great importance. Therefore, we aimed to compare the effects of home-based versus center-based aerobic exercise on the cardiopulmonary and functional capacities, quality of life and quality of sleep of overweight non-dialysis-dependent patients with CKD (NDD-CKD). Forty sedentary overweight patients CKD stages 3 and 4 were randomly assigned to an exercise group [home-based group (n = 12) or center-based exercise group (n = 13)] or to a control group (n = 15) that did not perform any exercise. Cardiopulmonary exercise test, functional capacity tests, quality of life, quality of sleep and clinical parameters were assessed at baseline, 12 and 24 weeks. The VO 2peak and all cardiopulmonary parameters evaluated were similarly improved (p < 0.05) after 12 and 24 weeks in both exercise groups. The functional capacity tests improved during the follow-up in the home-based group (p < 0.05) and reached values similar to those obtained in the center-based group. The benefits achieved in both exercise groups were also reflected in improvement of quality of life and sleep (p < 0.05). No differences were observed between the exercise groups, and no changes in any of the parameters investigated were found in the control group. Home-based aerobic training was as effective as center-based training in improving the physical and functional capabilities, quality of life and sleep in overweight NDD-CKD patients.

Impaired chronotropic and vasodilator reserves limit exercise capacity in patients with heart failure and a preserved ejection fraction.

PubMed

Borlaug, Barry A; Melenovsky, Vojtech; Russell, Stuart D; Kessler, Kristy; Pacak, Karel; Becker, Lewis C; Kass, David A

2006-11-14

Nearly half of patients with heart failure have a preserved ejection fraction (HFpEF). Symptoms of exercise intolerance and dyspnea are most often attributed to diastolic dysfunction; however, impaired systolic and/or arterial vasodilator reserve under stress could also play an important role. Patients with HFpEF (n=17) and control subjects without heart failure (n=19) generally matched for age, gender, hypertension, diabetes mellitus, obesity, and the presence of left ventricular hypertrophy underwent maximal-effort upright cycle ergometry with radionuclide ventriculography to determine rest and exercise cardiovascular function. Resting cardiovascular function was similar between the 2 groups. Both had limited exercise capacity, but this was more profoundly reduced in HFpEF patients (exercise duration 180+/-71 versus 455+/-184 seconds; peak oxygen consumption 9.0+/-3.4 versus 14.4+/-3.4 mL x kg(-1) x min(-1); both P<0.001). At matched low-level workload, HFpEF subjects displayed approximately 40% less of an increase in heart rate and cardiac output and less systemic vasodilation (all P<0.05) despite a similar rise in end-diastolic volume, stroke volume, and contractility. Heart rate recovery after exercise was also significantly delayed in HFpEF patients. Exercise capacity correlated with the change in cardiac output, heart rate, and vascular resistance but not end-diastolic volume or stroke volume. Lung blood volume and plasma norepinephrine levels rose similarly with exercise in both groups. HFpEF patients have reduced chronotropic, vasodilator, and cardiac output reserve during exercise compared with matched subjects with hypertensive cardiac hypertrophy. These limitations cannot be ascribed to diastolic abnormalities per se and may provide novel therapeutic targets for interventions to improve exercise capacity in this disorder.

Comparison of Watermelon and Carbohydrate Beverage on Exercise-Induced Alterations in Systemic Inflammation, Immune Dysfunction, and Plasma Antioxidant Capacity.

PubMed

Shanely, R Andrew; Nieman, David C; Perkins-Veazie, Penelope; Henson, Dru A; Meaney, Mary P; Knab, Amy M; Cialdell-Kam, Lynn

2016-08-22

Consuming carbohydrate- and antioxidant-rich fruits during exercise as a means of supporting and enhancing both performance and health is of interest to endurance athletes. Watermelon (WM) contains carbohydrate, lycopene, l-citrulline, and l-arginine. WM may support exercise performance, augment antioxidant capacity, and act as a countermeasure to exercise-induced inflammation and innate immune changes. Trained cyclists (n = 20, 48 ± 2 years) participated in a randomized, placebo controlled, crossover study. Subjects completed two 75 km cycling time trials after either 2 weeks ingestion of 980 mL/day WM puree or no treatment. Subjects drank either WM puree containing 0.2 gm/kg carbohydrate or a 6% carbohydrate beverage every 15 min during the time trials. Blood samples were taken pre-study and pre-, post-, 1 h post-exercise. WM ingestion versus no treatment for 2-weeks increased plasma l-citrulline and l-arginine concentrations (p < 0.0125). Exercise performance did not differ between WM puree or carbohydrate beverage trials (p > 0.05), however, the rating of perceived exertion was greater during the WM trial (p > 0.05). WM puree versus carbohydrate beverage resulted in a similar pattern of increase in blood glucose, and greater increases in post-exercise plasma antioxidant capacity, l-citrulline, l-arginine, and total nitrate (all p < 0.05), but without differences in systemic markers of inflammation or innate immune function. Daily WM puree consumption fully supported the energy demands of exercise, and increased post-exercise blood levels of WM nutritional components (l-citrulline and l-arginine), antioxidant capacity, and total nitrate, but without an influence on post-exercise inflammation and changes in innate immune function.

Physiological Stress Elicits Impaired Left Ventricular Function in Preterm-Born Adults.

PubMed

Huckstep, Odaro J; Williamson, Wilby; Telles, Fernando; Burchert, Holger; Bertagnolli, Mariane; Herdman, Charlotte; Arnold, Linda; Smillie, Robert; Mohamed, Afifah; Boardman, Henry; McCormick, Kenny; Neubauer, Stefan; Leeson, Paul; Lewandowski, Adam J

2018-03-27

Experimental and clinical studies show that prematurity leads to altered left ventricular (LV) structure and function with preserved resting LV ejection fraction (EF). Large-scale epidemiological data now links prematurity to increased early heart failure risk. The authors performed echocardiographic imaging at prescribed exercise intensities to determine whether preterm-born adults have impaired LV functional response to physical exercise. We recruited 101 normotensive young adults born preterm (n = 47; mean gestational age 32.8 ± 3.2 weeks) and term (n = 54) for detailed cardiovascular phenotyping. Full clinical resting and exercise stress echocardiograms were performed, with apical 4-chamber views collected while exercising at 40%, 60%, and 80% of peak exercise capacity, determined by maximal cardiopulmonary exercise testing. Preterm-born individuals had greater LV mass (p = 0.015) with lower peak systolic longitudinal strain (p = 0.038) and similar EF to term-born control subjects at rest (p = 0.62). However, by 60% exercise intensity, EF was 6.7% lower in preterm subjects (71.9 ± 8.7% vs 78.6 ± 5.4%; p = 0.004) and further declined to 7.3% below the term-born group at 80% exercise intensity (69.8 ± 6.4% vs 77.1 ± 6.3%; p = 0.004). Submaximal cardiac output reserve was 56% lower in preterm-born subjects versus term-born control subjects at 40% of peak exercise capacity (729 ± 1,162 ml/min/m 2 vs. 1,669 ± 937 ml/min/m 2 ; p = 0.021). LV length and resting peak systolic longitudinal strain predicted EF increase from rest to 60% exercise intensity in the preterm group (r = 0.68, p = 0.009 and r = 0.56, p = 0.031, respectively). Preterm-born young adults had impaired LV response to physiological stress when subjected to physical exercise, which suggested a reduced myocardial functional reserve that might help explain their increased risk of early heart failure. (Young Adult Cardiovascular Health sTudy [YACHT]; NCT02103231). Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Effect of Selective Heart Rate Slowing in Heart Failure With Preserved Ejection Fraction.

PubMed

Pal, Nikhil; Sivaswamy, Nadiya; Mahmod, Masliza; Yavari, Arash; Rudd, Amelia; Singh, Satnam; Dawson, Dana K; Francis, Jane M; Dwight, Jeremy S; Watkins, Hugh; Neubauer, Stefan; Frenneaux, Michael; Ashrafian, Houman

2015-11-03

Heart failure with preserved ejection fraction (HFpEF) is associated with significant morbidity and mortality but is currently refractory to therapy. Despite limited evidence, heart rate reduction has been advocated, on the basis of physiological considerations, as a therapeutic strategy in HFpEF. We tested the hypothesis that heart rate reduction improves exercise capacity in HFpEF. We conducted a randomized, crossover study comparing selective heart rate reduction with the If blocker ivabradine at 7.5 mg twice daily versus placebo for 2 weeks each in 22 symptomatic patients with HFpEF who had objective evidence of exercise limitation (peak oxygen consumption at maximal exercise [o2 peak] <80% predicted for age and sex). The result was compared with 22 similarly treated matched asymptomatic hypertensive volunteers. The primary end point was the change in o2 peak. Secondary outcomes included tissue Doppler-derived E/e' at echocardiography, plasma brain natriuretic peptide, and quality-of-life scores. Ivabradine significantly reduced peak heart rate compared with placebo in the HFpEF (107 versus 129 bpm; P<0.0001) and hypertensive (127 versus 145 bpm; P=0.003) cohorts. Ivabradine compared with placebo significantly worsened the change in o2 peak in the HFpEF cohort (-2.1 versus 0.9 mL·kg(-1)·min(-1); P=0.003) and significantly reduced submaximal exercise capacity, as determined by the oxygen uptake efficiency slope. No significant effects on the secondary end points were discernable. Our observations bring into question the value of heart rate reduction with ivabradine for improving symptoms in a HFpEF population characterized by exercise limitation. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02354573. © 2015 The Authors.

1RM prediction: a novel methodology based on the force-velocity and load-velocity relationships.

PubMed

Picerno, Pietro; Iannetta, Danilo; Comotto, Stefania; Donati, Marco; Pecoraro, Fabrizio; Zok, Mounir; Tollis, Giorgio; Figura, Marco; Varalda, Carlo; Di Muzio, Davide; Patrizio, Federica; Piacentini, Maria Francesca

2016-10-01

This study aimed to evaluate the accuracy of a novel approach for predicting the one-repetition maximum (1RM). The prediction is based on the force-velocity and load-velocity relationships determined from measured force and velocity data collected during resistance-training exercises with incremental submaximal loads. 1RM was determined as the load corresponding to the intersection of these two curves, where the gravitational force exceeds the force that the subject can exert. The proposed force-velocity-based method (FVM) was tested on 37 participants (23.9 ± 3.1 year; BMI 23.44 ± 2.45) with no specific resistance-training experience, and the predicted 1RM was compared to that achieved using a direct method (DM) in chest-press (CP) and leg-press (LP) exercises. The mean 1RM in CP was 99.5 kg (±27.0) for DM and 100.8 kg (±27.2) for FVM (SEE = 1.2 kg), whereas the mean 1RM in LP was 249.3 kg (±60.2) for DM and 251.1 kg (±60.3) for FVM (SEE = 2.1 kg). A high correlation was found between the two methods for both CP and LP exercises (0.999, p < 0.001). Good agreement between the two methods emerged from the Bland and Altman plot analysis. These findings suggest the use of the proposed methodology as a valid alternative to other indirect approaches for 1RM prediction. The mathematical construct is simply based on the definition of the 1RM, and it is fed with subject's muscle strength capacities measured during a specific exercise. Its reliability is, thus, expected to be not affected by those factors that typically jeopardize regression-based approaches.

Usefulness of the 6-minute walk test as a screening test for pulmonary arterial enlargement in COPD

PubMed Central

Oki, Yutaro; Kaneko, Masahiro; Fujimoto, Yukari; Sakai, Hideki; Misu, Shogo; Mitani, Yuji; Yamaguchi, Takumi; Yasuda, Hisafumi; Ishikawa, Akira

2016-01-01

Purpose Pulmonary hypertension and exercise-induced oxygen desaturation (EID) influence acute exacerbation of COPD. Computed tomography (CT)-detected pulmonary artery (PA) enlargement is independently associated with acute COPD exacerbations. Associations between PA to aorta (PA:A) ratio and EID in patients with COPD have not been reported. We hypothesized that the PA:A ratio correlated with EID and that results of the 6-minute walk test (6MWT) would be useful for predicting the risk associated with PA:A >1. Patients and methods We retrospectively measured lung function, 6MWT, emphysema area, and PA enlargement on CT in 64 patients with COPD. The patients were classified into groups with PA:A ≤1 and >1. Receiver-operating characteristic curves were used to determine the threshold values with the best cutoff points to predict patients with PA:A >1. Results The PA:A >1 group had lower forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1:FVC ratio, diffusion capacity of lung carbon monoxide, 6MW distance, and baseline peripheral oxygen saturation (SpO2), lowest SpO2, highest modified Borg scale results, percentage low-attenuation area, and history of acute COPD exacerbations ≤1 year, and worse BODE (Body mass index, airflow Obstruction, Dyspnea, and Exercise) index results (P<0.05). Predicted PA:A >1 was determined for SpO2 during 6MWT (best cutoff point 89%, area under the curve 0.94, 95% confidence interval 0.88–1). SpO2 <90% during 6MWT showed a sensitivity of 93.1, specificity of 94.3, positive predictive value of 93.1, negative predictive value of 94.3, positive likelihood ratio of 16.2, and negative likelihood ratio of 0.07. Conclusion Lowest SpO2 during 6MWT may predict CT-measured PA:A, and lowest SpO2 <89% during 6MWT is excellent for detecting pulmonary hypertension in COPD. PMID:27920514

Sildenafil increased exercise capacity during hypoxia at low altitudes and at Mount Everest base camp: a randomized, double-blind, placebo-controlled crossover trial.

PubMed

Ghofrani, Hossein A; Reichenberger, Frank; Kohstall, Markus G; Mrosek, Eike H; Seeger, Timon; Olschewski, Horst; Seeger, Werner; Grimminger, Friedrich

2004-08-03

Alveolar hypoxia causes pulmonary hypertension and enhanced right ventricular afterload, which may impair exercise tolerance. The phosphodiesterase-5 inhibitor sildenafil has been reported to cause pulmonary vasodilatation. To investigate the effects of sildenafil on exercise capacity under conditions of hypoxic pulmonary hypertension. Randomized, double-blind, placebo-controlled crossover study. University Hospital Giessen, Giessen, Germany, and the base camp on Mount Everest. 14 healthy mountaineers and trekkers. Systolic pulmonary artery pressure, cardiac output, and peripheral arterial oxygen saturation at rest and during assessment of maximum exercise capacity on cycle ergometry 1) while breathing a hypoxic gas mixture with 10% fraction of inspired oxygen at low altitude (Giessen) and 2) at high altitude (the Mount Everest base camp). Oral sildenafil, 50 mg, or placebo. At low altitude, acute hypoxia reduced arterial oxygen saturation to 72.0% (95% CI, 66.5% to 77.5%) at rest and 60.8% (CI, 56.0% to 64.5%) at maximum exercise capacity. Systolic pulmonary artery pressure increased from 30.5 mm Hg (CI, 26.0 to 35.0 mm Hg) at rest to 42.9 mm Hg (CI, 35.6 to 53.5 mm Hg) during exercise in participants taking placebo. Sildenafil, 50 mg, significantly increased arterial oxygen saturation during exercise (P = 0.005) and reduced systolic pulmonary artery pressure at rest (P < 0.001) and during exercise (P = 0.031). Of note, sildenafil increased maximum workload (172.5 W [CI, 147.5 to 200.0 W]) vs. 130.6 W [CI, 108.8 to 150.0 W]); P < 0.001) and maximum cardiac output (P < 0.001) compared with placebo. At high altitude, sildenafil had no effect on arterial oxygen saturation at rest and during exercise compared with placebo. However, sildenafil reduced systolic pulmonary artery pressure at rest (P = 0.003) and during exercise (P = 0.021) and increased maximum workload (P = 0.002) and cardiac output (P = 0.015). At high altitude, sildenafil exacerbated existing headache in 2 participants. The study did not examine the effects of sildenafil on normoxic exercise tolerance. Sildenafil reduces hypoxic pulmonary hypertension at rest and during exercise while maintaining gas exchange and systemic blood pressure. To the authors' knowledge, sildenafil is the first drug shown to increase exercise capacity during severe hypoxia both at sea level and at high altitude.

Evaluation of exercise capacity after severe stroke using robotics-assisted treadmill exercise: a proof-of-concept study.

PubMed

Stoller, O; de Bruin, E D; Schindelholz, M; Schuster, C; de Bie, R A; Hunt, K J

2013-01-01

Robotics-assisted treadmill exercise (RATE) with focus on motor recovery has become popular in early post-stroke rehabilitation but low endurance for exercise is highly prevalent in these individuals. This study aimed to develop an exercise testing method using robotics-assisted treadmill exercise to evaluate aerobic capacity after severe stroke. Constant load testing (CLT) based on body weight support (BWS) control, and incremental exercise testing (IET) based on guidance force (GF) control were implemented during RATE. Analyses focussed on step change, step response kinetics, and peak performance parameters of oxygen uptake. Three subjects with severe motor impairment 16-23 days post-stroke were included. CLT yielded reasonable step change values in oxygen uptake, whereas response kinetics of oxygen uptake showed low goodness of fit. Peak performance parameters were not obtained during IET. Exercise testing in post-stroke individuals with severe motor impairments using a BWS control strategy for CLT is deemed feasible and safe. Our approach yielded reasonable results regarding cardiovascular performance parameters. IET based on GF control does not provoke peak cardiovascular performance due to uncoordinated walking patterns. GF control needs further development to optimally demand active participation during RATE. The findings warrant further research regarding the evaluation of exercise capacity after severe stroke.

Beet Root Juice: An Ergogenic Aid for Exercise and the Aging Brain.

PubMed

Petrie, Meredith; Rejeski, W Jack; Basu, Swati; Laurienti, Paul J; Marsh, Anthony P; Norris, James L; Kim-Shapiro, Daniel B; Burdette, Jonathan H

2017-09-01

Exercise has positive neuroplastic effects on the aging brain. It has also been shown that ingestion of beet root juice (BRJ) increases blood flow to the brain and enhances exercise performance. Here, we examined whether there are synergistic effects of BRJ and exercise on neuroplasticity in the aging brain. Peak metabolic equivalent (MET) capacity and resting-state magnetic resonance imaging functional brain network organization are reported on 26 older (mean age = 65.4 years) participants randomly assigned to 6 weeks of exercise + BRJ or exercise + placebo. Somatomotor community structure consistency was significantly enhanced in the exercise + BRJ group following the intervention (MBRJ = -2.27, SE = 0.145, MPlacebo = -2.89, SE = 0.156, p = .007). Differences in second-order connections between the somatomotor cortex and insular cortex were also significant; the exercise + BRJ group (M = 3.28, SE = 0.167) had a significantly lower number of connections than exercise + placebo (M = 3.91, SE = 0.18, p = .017) following the intervention. Evaluation of peak MET capacity revealed a trend for the exercise + BRJ group to have higher MET capacity following the intervention. Older adults who exercised and consumed BRJ demonstrated greater consistency within the motor community and fewer secondary connections with the insular cortex compared with those who exercised without BRJ. The exercise + BRJ group had brain networks that more closely resembled those of younger adults, showing the potential enhanced neuroplasticity conferred by combining exercise and BRJ consumption. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

High-Intensity Interval Training for Severe Left Ventricular Dysfunction Treated with Left Ventricular Assist Device.

PubMed

Ugata, Yusuke; Wada, Hiroshi; Sakakura, Kenichi; Ibe, Tatsuro; Ito, Miyuki; Ikeda, Nahoko; Fujita, Hideo; Momomura, Shin-Ichi

2018-01-27

Aerobic training based on anaerobic threshold (AT) is well-known to improve cardiac function, exercise capacity, and long-term outcomes of patients with heart failure. Recent reports suggested that high-intensity interval training (HIIT) for patients with cardiovascular disease may improve cardiopulmonary exercise capacity. We present a 61-year-old male patient of severe left ventricular dysfunction with left ventricular assisted device (LVAD). Following HIIT for 8 weeks, exercise capacity and muscle strength have improved without worsening left ventricular function. Our case showed the possibility that HIIT was feasible and effective even in patients with LVAD.

Effect of energy drink dose on exercise capacity, heart rate recovery and heart rate variability after high-intensity exercise.

PubMed

An, Sang Min; Park, Jong Suk; Kim, Sang Ho

2014-03-01

The purpose of this research was to investigate the effects of exercise capacity, heart rate recovery and heart rate variability after high-intensity exercise on caffeine concentration of energy drink. The volunteers for this study were 15 male university student. 15 subjects were taken basic physical examinations such as height, weight and BMI before the experiment. Primary tests were examined of VO2max per weight of each subjects by graded exercise test using Bruce protocol. Each of five subject was divided 3 groups (CON, ECGⅠ, ECGⅡ) by matched method based on weight and VO2max per weight what gained of primary test for minimize the differences of exercise capacity and ingestion of each groups. For the secondary tests, the groups of subjects were taken their materials before and after exercise as a blind test. After the ingestion, subjects were experimented on exercise test of VO2max 80% by treadmill until the all-out. Heart rate was measured by 1minute interval, and respiratory variables were analyzed VO2, VE, VT, RR and so on by automatic respiratory analyzer. And exercise exhaustion time was determined by stopwatch. Moreover, HRV was measured after exercise and recovery 3 min. Among the intake groups, ECGⅡ was showed the longest of exercise exhaustion time more than CON group (p = .05). Result of heart rate during exercise according to intake groups, there was significant differences of each time (p < .001), however, not significant differences of each groups and group verse time (p > .05). Result of RPE during exercise according to intake groups, there was significant differences of each time (p < .001), however, not significant differences of each groups and group verse time (p > .05). In conclusion, EDGⅡ showed the significant increase of exercise exhaustion time more than CON group (p=.05) and not significant differences in HR, RPE, RER, HRV, HRR, blood pressure (p > .05). Therefore, 2.5 mg/kg(-1) ingestion of energy drink might be positive effect to increase exercise performance capacity without side-effect in cardiovascular disease.

Benefits of supplemental oxygen in exercise training in nonhypoxemic chronic obstructive pulmonary disease patients.

PubMed

Emtner, Margareta; Porszasz, Janos; Burns, Mary; Somfay, Attila; Casaburi, Richard

2003-11-01

Supplemental oxygen improves exercise tolerance of normoxemic and hypoxemic chronic obstructive pulmonary disease (COPD) patients. We determined whether nonhypoxemic COPD patients undergoing exercise training while breathing supplemental oxygen achieve higher intensity and therefore improve exercise capacity more than patients breathing air. A double-blinded trial was performed involving 29 nonhypoxemic patients (67 years, exercise SaO2 > 88%) with COPD (FEV1 = 36% predicted). All exercised on cycle ergometers for 45 minutes, 3 times per week for 7 weeks at high-intensity targets. During exercise, they received oxygen (3 L/minute) (n = 14) or compressed air (3 L/minute) (n = 15). Both groups had a higher exercise tolerance after training and when breathing oxygen. However, the oxygen-trained group increased the training work rate more rapidly than the air-trained group. The mean +/- SD work rate during the last week was 62 +/- 19 W (oxygen-trained group) and 52 +/- 22 W (air-trained group) (p < 0.01). After training, endurance in constant work rate tests increased more in the oxygen-trained group (14.5 minutes) than in the air-trained group (10.5 minutes) (p < 0.05). At isotime, the breathing rate decreased four breaths per minute in the oxygen-trained group and one breath per minute in the air-trained group (p = 0.001). We conclude that supplemental oxygen provided during high-intensity training yields higher training intensity and evidence of gains in exercise tolerance in laboratory testing.

Changes in systolic arterial pressure variability are associated with the decreased aerobic performance of rats subjected to physical exercise in the heat.

PubMed

Müller-Ribeiro, Flávia C; Wanner, Samuel P; Santos, Weslley H M; Malheiros-Lima, Milene R; Fonseca, Ivana A T; Coimbra, Cândido C; Pires, Washington

2017-01-01

Enhanced cardiovascular strain is one of the factors that explains degraded aerobic capacity in hot environments. The cardiovascular system is regulated by the autonomic nervous system, whose activity can be indirectly evaluated by analyzing heart rate variability (HRV) and systolic arterial pressure (SAP) variability. However, no study has addressed whether HRV or SAP variability can predict aerobic performance during a single bout of exercise. Therefore, this study aimed to investigate whether there is an association between cardiovascular variability and performance in rats subjected to treadmill running at two ambient temperatures. In addition, this study investigated whether the heat-induced changes in cardiovascular variability and reductions in performance are associated with each other. Male Wistar rats were implanted with a catheter into their carotid artery for pulsatile blood pressure recordings. After recovery from surgery, the animals were subjected to incremental-speed exercise until they were fatigued under temperate (25°C) and hot (35°C) conditions. Impaired performance and exaggerated cardiovascular responses were observed in the hot relative to the temperate environment. Significant and negative correlations between most of the SAP variability components (standard deviation, variance, very low frequency [VLF], and low frequency [LF]) at the earlier stages of exercise and total exercise time were observed in both environmental conditions. Furthermore, the heat-induced changes in the sympathetic components of SAP variability (VLF and LF) were associated with heat-induced impairments in performance. Overall, the results indicate that SAP variability at the beginning of exercise predicts the acute performance of rats. Our findings also suggest that heat impairments in aerobic performance are associated with changes in cardiovascular autonomic control. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of preoperative change in physical function on postoperative recovery: argument supporting prehabilitation for colorectal surgery.

PubMed

Mayo, Nancy E; Feldman, Liane; Scott, Susan; Zavorsky, Gerald; Kim, Do Jun; Charlebois, Patrick; Stein, Barry; Carli, Francesco

2011-09-01

Abdominal surgery represents a physiologic stress and is associated with a period of recovery during which functional capacity is often diminished. "Prehabilitation" is a program to increase functional capacity in anticipation of an upcoming stressor. We reported recently the results of a randomized trial comparing 2 prehabilitation programs before colorectal surgery (stationary cycling plus weight training versus a recommendation to increase walking coupled with breathing exercises); however, adherence to the programs was low. The objectives of this study were to estimate: (1) the extent to which physical function could be improved with either prehabilitation program and identify variables associated with response; and (2) the impact of change in preoperative function on postoperative recovery. This study involved a reanalysis of data arising from a randomized trial. The primary outcome measure was functional walking capacity measured by the Six-Minute Walk Test; secondary outcomes were anxiety, depression, health-related quality of life, and complications (Clavien classification). Multiple linear regression was used to estimate the extent to which key variables predicted change in functional walking capacity over the prehabilitation and follow-up periods. We included 95 people who completed the prehabilitation phase (median, 38 days; interquartile range, 22-60), and 75 who were also evaluated postoperatively (mean, 9 weeks). During prehabilitation, 33% improved their physical function, 38% stayed within 20 m of their baseline score, and 29% deteriorated. Among those who improved, mental health, vitality, self-perceived health, and peak exercise capacity also increased significantly. Women were less likely to improve; low baseline walking capacity, anxiety, and the belief that fitness aids recovery were associated with improvements during prehabilitation. In the postoperative phase, the patients who had improved during prehabilitation were also more likely to have recovered to their baseline walking capacity than those with no change or deterioration (77% vs 59% and 32%; P = .0007). Patients who deteriorated were at greater risk of complications requiring reoperation and/or intensive care management. Significant predictors of poorer recovery included deterioration during prehabilitation, age >75 years, high anxiety, complications requiring intervention, and timing of follow-up assessment. In a group of patients undergoing scheduled colorectal surgery, meaningful changes in functional capacity can be achieved over several weeks of prehabilitation. Patients and those who care for them, especially those with poor physical capacity, should consider a prehabilitation regimen to enhance functional exercise capacity before colectomy. Copyright © 2011 Mosby, Inc. All rights reserved.

Exercise Tolerance Testing in a Prospective Cohort of Adolescents with Chronic Fatigue Syndrome and Recovered Controls Following Infectious Mononucleosis

PubMed Central

Katz, Ben Z.; Boas, Steven; Shiraishi, Yukiko; Mears, Cynthia J.; Taylor, Renee

2010-01-01

Objective Six months following acute infectious mononucleosis (IM), 13%, of adolescents meet criteria for chronic fatigue syndrome (CFS). We measured exercise tolerance in adolescents with CFS and controls 6 months following IM. Study design 21 adolescents with CFS 6 months following IM and 21 recovered controls performed a maximal incremental exercise tolerance test with breath-by-breath gas analysis. Values expressed are mean ± standard deviation. Results The adolescents diagnosed with CFS and controls did not differ in age, weight, body-mass index or peak work capacity. Lower VO2 (oxygen consumption) peak percent of predicted was seen in adolescents with CFS compared with controls (CFS 99.3 ± 16.6 vs control 110.7 ± 19.9, p = 0.05). Peak oxygen pulse also was lower in adolescents with CFS compared with recovered controls (CFS 12.4 ± 2.9 vs controls 14.9 ± 4.3, p = 0.03). Conclusions Adolescents with CFS 6 months following IM have a lower degree of fitness and efficiency of exercise than recovered adolescents. Whether these abnormal exercise findings are a cause or effect of CFS is unknown. IM can lead to both fatigue and measurable changes in exercise testing in a subset of adolescents. PMID:20447647

Exercise countermeasures for bed rest deconditioning

NASA Technical Reports Server (NTRS)

Greenleaf, John (Editor)

1989-01-01

The major objectives were to evaluate the efficiency of different modes of exercise (isotonic and isokinetic) for countering the effects of bed rest deconditioning on work capacity (peak oxygen uptake), muscular strength, orthostatic tolerance, posture, equilibrium and gait; and to collect additional data of a more fundamental nature to help understand how these deconditioning responses occur. These data will be used for writing prescriptions for exercise to be utilized by astronauts for maintaining work capacity and well-being on Freedom Station, and to determine what exercise devices should be place in the station.

Effects of carbohydrate ingestion 15 min before exercise on endurance running capacity.

PubMed

Tokmakidis, Savvas P; Karamanolis, Ioannis A

2008-06-01

This study examined the effects of pre-exercise carbohydrate ingestion on exercise metabolism and endurance running capacity. Eleven active subjects (VO(2) (max) 49.0 +/- 1.7 mL x kg(-1) x min(-1), mean +/- SE) performed two exercise trials 15 min after ingesting glucose (G; 1 g x kg body mass(-1)) and placebo (CON). Each subject ran on a level treadmill for 5 min at 60%, 45 min at 70%, and then at 80% of VO(2) (max) until exhaustion. Serum glucose and plasma insulin reached their peak concentrations (p < 0.01) 15 min after glucose ingestion and declined at the onset of exercise. Serum glycerol concentrations were lower (p < 0.01) in the G trial than in the CON trial after 30 min of exercise to exhaustion. In addition, after 45 min of exercise to exhaustion, the levels of free fatty acids were lower in G than in CON (p < 0.05). No differences were observed in carbohydrate oxidation rates during exercise between treatments (G, 2.53 +/- 0.08 g x min(-1); CON, 2.40 +/- 0.09 g x min(-1)). Time to exhaustion was 12.8% longer in G (p < 0.01) than in CON. These results suggest that glucose ingestion 15 min before prolonged exercise provides an additional carbohydrate source to the exercising muscle, thus improving endurance running capacity.

Patient-Reported Dyspnea Correlates Poorly with Aerobic Exercise Capacity Measured During Cardiopulmonary Exercise Testing.

PubMed

Gaspard, Dany; Kass, Jonathan; Akers, Stephen; Hunter, Krystal; Pratter, Melvin

2017-10-01

Patient-reported dyspnea plays a central role in assessing cardiopulmonary disease. There is little evidence, however, that dyspnea correlates with objective exercise capacity measurements. If the correlation is poor, dyspnea as a proxy for objective assessment may be misleading. To compare patient's perception of dyspnea with maximum oxygen uptake (MaxVO2) during cardiopulmonary exercise testing (CPET). Fifty patients undergoing CPET for dyspnea evaluation were studied prospectively. Dyspnea assessment was measured by a metabolic equivalent of task (METs) table, Mahler Dyspnea Index, Borg Index, number of blocks walked, and flights of stairs climbed before stopping due to dyspnea. These descriptors were compared to MaxVO2. MaxVO2 showed low correlation with METs table (r = 0.388, p = 0.005) and no correlation with Mahler Index (r = 0.24, p = 0.093), Borg Index (r = -0.017, p = 0.905), number of blocks walked (r = 0.266, p = 0.077) or flights of stairs climbed (r = 0.188, p = 0.217). When adjusted for weight (maxVO2/kg), there was significant correlation between MaxVO2 and METs table (r = 0.711, p < 0.001), moderate correlation with blocks walked (r = 0.614, p < 0.001), and low correlation with Mahler Index (r = 0.488 p = 0.001), Borg Index (r = -0.333 p = 0.036), and flights of stairs (r = 0.457 p = 0.004). Subgroup analysis showed worse correlation when patients with normal CPET were excluded (12/50 excluded). Patients with BMI < 30 had no correlation between Max VO2 and the assessment methods, while patients with BMI > 30 had moderate correlation between MaxVO2 and METs table (r = 0.568, p = 0.002). Patient-reported dyspnea correlates poorly with MaxVO2 and fails to predict exercise capacity. Reliance on reported dyspnea may result in suboptimal categorization of cardiopulmonary disease severity.

Pioglitazone ameliorates the lowered exercise capacity and impaired mitochondrial function of the skeletal muscle in type 2 diabetic mice.

PubMed

Takada, Shingo; Hirabayashi, Kagami; Kinugawa, Shintaro; Yokota, Takashi; Matsushima, Shouji; Suga, Tadashi; Kadoguchi, Tomoyasu; Fukushima, Arata; Homma, Tsuneaki; Mizushima, Wataru; Masaki, Yoshihiro; Furihata, Takaaki; Katsuyama, Ryoichi; Okita, Koichi; Tsutsui, Hiroyuki

2014-10-05

We have reported that exercise capacity is reduced in high fat diet (HFD)-induced diabetic mice, and that this reduction is associated with impaired mitochondrial function in skeletal muscle (SKM). However, it remains to be clarified whether the treatment of diabetes ameliorates the reduced exercise capacity. Therefore, we examined whether an insulin-sensitizing drug, pioglitazone, could improve exercise capacity in HFD mice. C57BL/6J mice were fed a normal diet (ND) or HFD, then treated with or without pioglitazone (3 mg/kg/day) to yield the following 4 groups: ND+vehicle, ND+pioglitazone, HFD+vehicle, and HFD+pioglitazone (n=10 each). After 8 weeks, body weight, plasma glucose, and insulin in the HFD+vehicle were significantly increased compared to the ND+vehicle group. Pioglitazone normalized the insulin levels in HFD-fed mice, but did not affect the body weight or plasma glucose. Exercise capacity determined by treadmill tests was significantly reduced in the HFD+vehicle, and this reduction was almost completely ameliorated in HFD+pioglitazone mice. ADP-dependent mitochondrial respiration, complex I and III activities, and citrate synthase activity were significantly decreased in the SKM of the HFD+vehicle animals, and these decreases were also attenuated by pioglitazone. NAD(P)H oxidase activity was significantly increased in the HFD+vehicle compared with the ND+vehicle, and this increase was ameliorated in HFD+pioglitazone mice. Pioglitazone improved the exercise capacity in diabetic mice, which was due to the improvement in mitochondrial function and attenuation of oxidative stress in the SKM. Our data suggest that pioglitazone may be useful as an agent for the treatment of diabetes mellitus. Copyright © 2014 Elsevier B.V. All rights reserved.

Internet Program for Physical Activity and Exercise Capacity in Children With Juvenile Idiopathic Arthritis: A Multicenter Randomized Controlled Trial.

PubMed

Armbrust, Wineke; Bos, G J F Joyce; Wulffraat, Nico M; van Brussel, Marco; Cappon, Jeannette; Dijkstra, Pieter U; Geertzen, Jan H B; Legger, G Elizabeth; van Rossum, Marion A J; Sauer, Pieter J J; Lelieveld, Otto T H M

2017-07-01

To determine the effects of Rheumates@Work, an internet-based program supplemented with 4 group sessions, aimed at improving physical activity, exercise capacity, health-related quality of life (HRQoL), and participation in children with juvenile idiopathic arthritis. Patients were recruited from 3 pediatric rheumatology centers in The Netherlands for an observer-blinded, randomized controlled multicenter trial. Physical activity level, time spent in rest, light, and moderate-to-vigorous physical activity (MVPA) were recorded in a diary and with an accelerometer, before intervention, after intervention, and at followup after 3 and 12 months (intervention group only). Exercise capacity was assessed using the Bruce treadmill protocol, HRQoL was assessed with the Pediatric Quality of Life Inventory generic core scale, and participation in school and in physical education classes were assessed by questionnaire. The intervention group consisted of 28 children, and there were 21 children in the control group. MVPA , exercise capacity, and participating in school and physical education classes improved significantly in the intervention group. HRQoL improved in the control group. No significant differences were found between groups. The effect of Rheumates@Work on physical activity and exercise capacity lasted during the 12 months of followup. Improvements in physical activity were significantly better for the cohort starting in winter compared to the summer cohort. Rheumates@Work had a positive, albeit small, effect on physical activity, exercise capacity, and participation in school and physical education class in the intervention group. Improvements lasted for 12 months. Participants who started in winter showed the most improvement. Rheumates@Work had no effect on HRQoL. © 2016, American College of Rheumatology.

The Prognostic Role of Ventilatory Inefficiency and Exercise Capacity in Idiopathic Pulmonary Fibrosis.

PubMed

Vainshelboim, Baruch; Oliveira, Jose; Fox, Benjamin Daniel; Kramer, Mordechai Reuven

2016-08-01

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fatal interstitial lung disease associated with poor prognosis and limited effective treatment options. Reliable predictors of outcome in daily clinical practice are needed to determine high-risk patients for urgent lung transplantation referral. This study aimed to identify practical prognostic predictors of mortality using cardiopulmonary exercise testing (CPET) in IPF subjects. Thirty-four subjects with IPF (22 men and 12 women), median age 68 (range 50-81) y were prospectively studied. At baseline, all subjects were assessed with CPET and were followed up for 40 months from baseline. Receiver operating characteristic curve analysis was conducted to determine cut-off points of CPET variables for mortality, Cox regression analysis for survival using a log-rank test, and hazard ratio for death using a Wald test. Peak work rate <62 watts (P = .005), peak V̇O2 ≤13.8 mL/kg/min (P = .031), tidal volume reserve ≤0.48 L/breath (P = .010), minute ventilation to carbon dioxide (V̇E)/V̇CO2 ) ratio at the anaerobic threshold >34 (P = .02), and V̇E)/V̇O2 nadir >34 (P = .002) were detected as cut-off points associated with mortality. Non-survivor subjects were characterized by higher dyspnea levels, the presence of pulmonary hypertension assessed by echocardiography, pronounced inefficient ventilatory pattern, lower exercise capacity, and more severe desaturation during physical exertion. By the end of the study, 11 subjects (7 women and 4 men) died. Overall mean survival was 60%, 33.7 months (95% CI 30.2-37.2). This study provides simple, practical, and novel cut-off points for CPET as predictors of prognosis to identify high-risk IPF subjects. Impairment in exercise capacity and abnormal ventilatory responses during CPET were associated with poorer survival in IPF subjects. The findings suggest considering the use of CPET for IPF risk stratification and prediction of prognosis. (ClinicalTrials.gov registration NCT01499745.). Copyright © 2016 by Daedalus Enterprises.

Effects of obstructive sleep apnea and obesity on exercise function in children.

PubMed

Evans, Carla A; Selvadurai, Hiran; Baur, Louise A; Waters, Karen A

2014-06-01

Evaluate the relative contributions of weight status and obstructive sleep apnea (OSA) to cardiopulmonary exercise responses in children. Prospective, cross-sectional study. Participants underwent anthropometric measurements, overnight polysomnography, spirometry, cardiopulmonary exercise function testing on a cycle ergometer, and cardiac doppler imaging. OSA was defined as ≥ 1 obstructive apnea or hypopnea per hour of sleep (OAHI). The effect of OSA on exercise function was evaluated after the parameters were corrected for body mass index (BMI) z-scores. Similarly, the effect of obesity on exercise function was examined when the variables were adjusted for OAHI. Tertiary pediatric hospital. Healthy weight and obese children, aged 7-12 y. N/A. Seventy-one children were studied. In comparison with weight-matched children without OSA, children with OSA had a lower cardiac output, stroke volume index, heart rate, and oxygen consumption (VO2 peak) at peak exercise capacity. After adjusting for BMI z-score, children with OSA had 1.5 L/min (95% confidence interval -2.3 to -0.6 L/min; P = 0.001) lower cardiac output at peak exercise capacity, but minute ventilation and ventilatory responses to exercise were not affected. Obesity was only associated with physical deconditioning. Cardiac dysfunction was associated with the frequency of respiratory-related arousals, the severity of hypoxia, and heart rate during sleep. Children with OSA are exercise limited due to a reduced cardiac output and VO2 peak at peak exercise capacity, independent of their weight status. Comorbid OSA can further decrease exercise performance in obese children.

Effects of Exercise Training on Exercise Capacity in Pulmonary Arterial Hypertension: A Systematic Review of Clinical Trials.

PubMed

Babu, Abraham Samuel; Padmakumar, Ramachandran; Maiya, Arun G; Mohapatra, Aswini Kumar; Kamath, R L

2016-04-01

Pulmonary arterial hypertension (PAH) causes profound functional limitations and poor quality of life. Yet, there is only a limited literature available on the role of exercise training. This paper systematically reviews the effects of exercise training on exercise capacity in PAH. A systematic search of databases (PubMed, CINAHL, CENTRAL, Web of Science and PEDRo) was undertaken for English language articles published between 1(st) January 1980 and 31(st) March 2015. Quality rating for all articles was done using the Downs and Black scoring system. Fifteen articles of good (n=4), moderate (n=6) and poor (n=5) quality were included in the review. Exercise interventions included aerobic, resistance, inspiratory muscle training or a combination, for 6-18 weeks. Improvements were seen in exercise capacity (six minute walk distance (6MWD) and peak VO2) by 17-96m and 1.1-2.1ml/Kg/min, functional class by one class and quality of life, with minimal adverse events. There is evidence to recommend the use of exercise training as an adjunct to medical treatment in PAH. More clinical trials and research are required to assess the effects of different types of exercise programs in patients with PAH, while focussing on strong exercise endpoints to quantify the improvements seen with exercise training. Copyright © 2015 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Exercise Increases Markers of Spermatogenesis in Rats Selectively Bred for Low Running Capacity.

PubMed

Torma, Ferenc; Koltai, Erika; Nagy, Enikő; Ziaaldini, Mohammad Mosaferi; Posa, Aniko; Koch, Lauren G; Britton, Steven L; Boldogh, Istvan; Radak, Zsolt

2014-01-01

The oxidative stress effect of exercise training on testis function is under debate. In the present study we used a unique rat model system developed by artificial selection for low and high intrinsic running capacity (LCR and HCR, respectively) to evaluate the effects of exercise training on apoptosis and spermatogenesis in testis. Twenty-four 13-month-old male rats were assigned to four groups: control LCR (LCR-C), trained LCR (LCR-T), control HCR (HCR-C), and trained HCR (HCR-T). Ten key proteins connecting aerobic exercise capacity and general testes function were assessed, including those that are vital for mitochondrial biogenesis. The VO2 max of LCR-C group was about 30% lower than that of HCR-C rats, and the SIRT1 levels were also significantly lower than HCR-C. Twelve weeks of training significantly increased maximal oxygen consumption in LCR by nearly 40% whereas HCR remained unchanged. LCR-T had significantly higher levels of peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1α), decreased levels of reactive oxygen species and increased acetylated p53 compared to LCR-C, while training produced no significant changes for these measures in HCR rats. BAX and Blc-2 were not different among all four groups. The levels of outer dense fibers -1 (Odf-1), a marker of spermatogenesis, increased in LCR-T rats, but decreased in HCR-TR rats. Moreover, exercise training increased the levels of lactate dehydrogenase C (LDHC) only in LCR rats. These data suggest that rats with low inborn exercise capacity can increase whole body oxygen consumption and running exercise capacity with endurance training and, in turn, increase spermatogenesis function via reduction in ROS and heightened activity of p53 in testes.

[Insight into the training of patients with idiopathic inflammatory myopathy].

PubMed

Váncsa, Andrea

2016-09-01

Using current recommended treatment, a majority of patients with idiopathic inflammatory myopathy develop muscle impairment and poor health. Beneficial effects of exercise have been reported on muscle performance, aerobic capacity and health in chronic polymyositis and dermatomyositis, as well as in active disease and inclusion body myositis to some extent. Importantly, randomized controlled trials indicate that improved health and decreased clinical disease activity could be mediated through increased aerobic capacity. Recently, reports seeking pathomechanisms of the underlying effects of exercise on skeletal muscle indicate increased aerobic capacity (i.e. increased mitochondrial capacity and capillary density, reduced lactate levels), activation of genes of aerobic phenotype and muscle growth programs and down regulation of genes related to inflammation. Exercise contributes to both systemic and within-muscle adaptations demonstrating that it is fundamental for improving muscle performance and health in patients with idiopathic inflammatory myopathy. There is a need for randomized controlled trials to study the effects of exercise in patients with active disease and inclusion body myositis. Orv. Hetil., 2016, 157(39), 1557-1562.

Exercise recommendations for individuals with spinal cord injury.

PubMed

Jacobs, Patrick L; Nash, Mark S

2004-01-01

Persons with spinal cord injury (SCI) exhibit deficits in volitional motor control and sensation that limit not only the performance of daily tasks but also the overall activity level of these persons. This population has been characterised as extremely sedentary with an increased incidence of secondary complications including diabetes mellitus, hypertension and atherogenic lipid profiles. As the daily lifestyle of the average person with SCI is without adequate stress for conditioning purposes, structured exercise activities must be added to the regular schedule if the individual is to reduce the likelihood of secondary complications and/or to enhance their physical capacity. The acute exercise responses and the capacity for exercise conditioning are directly related to the level and completeness of the spinal lesion. Appropriate exercise testing and training of persons with SCI should be based on the individual's exercise capacity as determined by accurate assessment of the spinal lesion. The standard means of classification of SCI is by application of the International Standards for Classification of Spinal Cord Injury, written by the Neurological Standards Committee of the American Spinal Injury Association. Individuals with complete spinal injuries at or above the fourth thoracic level generally exhibit dramatically diminished cardiac acceleration with maximal heart rates less than 130 beats/min. The work capacity of these persons will be limited by reductions in cardiac output and circulation to the exercising musculature. Persons with complete spinal lesions below the T(10) level will generally display injuries to the lower motor neurons within the lower extremities and, therefore, will not retain the capacity for neuromuscular activation by means of electrical stimulation. Persons with paraplegia also exhibit reduced exercise capacity and increased heart rate responses (compared with the non-disabled), which have been associated with circulatory limitations within the paralysed tissues. The recommendations for endurance and strength training in persons with SCI do not vary dramatically from the advice offered to the general population. Systems of functional electrical stimulation activate muscular contractions within the paralysed muscles of some persons with SCI. Coordinated patterns of stimulation allows purposeful exercise movements including recumbent cycling, rowing and upright ambulation. Exercise activity in persons with SCI is not without risks, with increased risks related to systemic dysfunction following the spinal injury. These individuals may exhibit an autonomic dysreflexia, significantly reduced bone density below the spinal lesion, joint contractures and/or thermal dysregulation. Persons with SCI can benefit greatly by participation in exercise activities, but those benefits can be enhanced and the relative risks may be reduced with accurate classification of the spinal injury.

[Effects of aerobic exercise combined with resistance training on the cardiorespiratory fitness and exercise capacity of patients with stable coronary artery disease].

PubMed

Liu, S X; Chen, Y Y; Xie, K L; Zhang, W L

2017-12-24

Objective: To observe the effects of aerobic exercise combined with resistance training on the cardiorespiratory fitness and exercise capacity of patients with stable coronary artery disease (CAD) . Methods: From June 2014 to December 2015, 73 patients with stable CAD in our department were recruited and randomly assigned to two groups: the control group ( n= 38) and the exercise group ( n= 35) . Patients in both groups received conventional medical treatment for CAD and related cardiac health education. While for patients in exercise group, a twelve-week aerobic exercise combined with resistance training program were applied on top of conventional treatment and health education. Cardiorespiratory fitness and exercise capacity were evaluated by cardiopulmonary exercise testing. Results: (1) The exercise capacity was significantly increased in the exercise group after 12 weeks training as compared to baseline level: peak oxygen uptake per kilogram ( (26.25±5.14) ml·kg(-1)·min(-1) vs. (20.88±4.59) ml·kg(-1)·min(-1)) , anaerobic threshold ( (15.24±2.75) ml·kg(-1)·min(-1) vs. (13.52±2.92) ml·kg(-1)·min(-1)], peak oxygen pulse ( (11.91±2.89) ml/beat vs. (9.77±2.49) ml/beat) , peak Watts ( (113.2±34.0) W vs. (103.7±27.9) W) , peak metabolic equivalent ( (7.57±1.46) METs vs. (6.00±1.32) METs) (all P< 0.05 vs. baseline) . (2) The degree of improvement of peak oxygen uptake per kilogram ( (26.25±5.14) ml·kg(-1)·min(-1) vs. (22.32±4.00) ml·kg(-1)·min(-1)) , anaerobic threshold ( (15.24±2.75) ml·kg(-1)·min(-1) vs. (13.76±2.51) ml·kg(-1)·min(-1)) , peak oxygen pulse ( (11.91±2.89) ml/beat vs. (9.99±2.15) ml/beat) and peak metabolic equivalent ( (7.57±1.46) METs vs. (6.47±1.17) METs) were significantly higher in exercise group than in control group (all P< 0.05) . Conclusion: Aerobic training at an aerobic threshold level combined with Thera-band resistance training is safe for patients with stable coronary artery disease. This combined exercise program can significantly improve the cardiorespiratory fitness and exercise capacity of patients with stable coronary artery disease.

Dietary nitrate restores compensatory vasodilation and exercise capacity in response to a compromise in oxygen delivery in the noncompensator phenotype.

PubMed

Bentley, Robert F; Walsh, Jeremy J; Drouin, Patrick J; Velickovic, Aleksandra; Kitner, Sarah J; Fenuta, Alyssa M; Tschakovsky, Michael E

2017-09-01

Recently, dietary nitrate supplementation has been shown to improve exercise capacity in healthy individuals through a potential nitrate-nitrite-nitric oxide pathway. Nitric oxide has been shown to play an important role in compensatory vasodilation during exercise under hypoperfusion. Previously, we established that certain individuals lack a vasodilation response when perfusion pressure reductions compromise exercising muscle blood flow. Whether this lack of compensatory vasodilation in healthy, young individuals can be restored with dietary nitrate supplementation is unknown. Six healthy (21 ± 2 yr), recreationally active men completed a rhythmic forearm exercise. During steady-state exercise, the exercising arm was rapidly transitioned from an uncompromised (below heart) to a compromised (above heart) position, resulting in a reduction in local pressure of -31 ± 1 mmHg. Exercise was completed following 5 days of nitrate-rich (70 ml, 0.4 g nitrate) and nitrate-depleted (70 ml, ~0 g nitrate) beetroot juice consumption. Forearm blood flow (in milliliters per minute; brachial artery Doppler and echo ultrasound), mean arterial blood pressure (in millimeters of mercury; finger photoplethysmography), exercising forearm venous effluent (ante-cubital vein catheter), and plasma nitrite concentrations (chemiluminescence) revealed two distinct vasodilatory responses: nitrate supplementation increased (plasma nitrite) compared with placebo (245 ± 60 vs. 39 ± 9 nmol/l; P < 0.001), and compensatory vasodilation was present following nitrate supplementation (568 ± 117 vs. 714 ± 139 ml ⋅ min -1 ⋅ 100 mmHg -1 ; P = 0.005) but not in placebo (687 ± 166 vs. 697 ± 171 min -1 ⋅ 100 mmHg -1 ; P = 0.42). As such, peak exercise capacity was reduced to a lesser degree (-4 ± 39 vs. -39 ± 27 N; P = 0.01). In conclusion, dietary nitrate supplementation during a perfusion pressure challenge is an effective means of restoring exercise capacity and enabling compensatory vasodilation. NEW & NOTEWORTHY Previously, we identified young, healthy persons who suffer compromised exercise tolerance when exercising muscle perfusion pressure is reduced as a result of a lack of compensatory vasodilation. The ability of nitrate supplementation to restore compensatory vasodilation in such noncompensators is unknown. We demonstrated that beetroot juice supplementation led to compensatory vasodilation and restored perfusion and exercise capacity. Elevated plasma nitrite is an effective intervention for correcting the absence of compensatory vasodilation in the noncompensator phenotype. Copyright © 2017 the American Physiological Society.

Principles of exercise physiology: responses to acute exercise and long-term adaptations to training.

PubMed

Rivera-Brown, Anita M; Frontera, Walter R

2012-11-01

Physical activity and fitness are associated with a lower prevalence of chronic diseases, such as heart disease, cancer, high blood pressure, and diabetes. This review discusses the body's response to an acute bout of exercise and long-term physiological adaptations to exercise training with an emphasis on endurance exercise. An overview is provided of skeletal muscle actions, muscle fiber types, and the major metabolic pathways involved in energy production. The importance of adequate fluid intake during exercise sessions to prevent impairments induced by dehydration on endurance exercise, muscular power, and strength is discussed. Physiological adaptations that result from regular exercise training such as increases in cardiorespiratory capacity and strength are mentioned. The review emphasizes the cardiovascular and metabolic adaptations that lead to improvements in maximal oxygen capacity. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Comparative analysis of the 1-mile run test evaluation formulae: assessment of aerobic capacity in male law enforcement officers aged 20-23 years.

PubMed

Kayihan, Gürhan; Özkan, Ali; Köklü, Yusuf; Eyuboğlu, Ender; Akça, Firat; Koz, Mitat; Ersöz, Gülfem

2014-04-01

The purpose of this study was to compare values of aerobic performance in the 1-mile run test (1-MRT) using different formulae. Aerobic capacities of 351 male volunteers working for the Turkish National Police within the age range of 20-23 years were evaluated by the 1-MRT and the 20-metre shuttle run (20-MST). VO2max values were estimated by the prediction equations developed by George et al. (1993), Cureton et al. (1995) and Kline et al. (1987) for the 1-MRT and by Leger and Lambert (1982) for the 20-MST. The difference between the results of the different formulae was significant (p = 0.000). The correlation coefficient between the estimated VO2max using Cureton's equation, George's equation, Kline's equation and the 20-MST were 0.691 (p < 0.001), 0.486 (p < 0.001) and 0.608 (p < 0.001), respectively. The highest correlation coefficient was between the VO2max estimated by the 20-MST and Cureton's equation. Similarly, the highest correlation coefficient (r = -0.779) was between the 1-mile run time and the VO2max estimated by Cureton's equation. When analysing more vigorous exercise than sub-maximal exercise, we suggest that Cureton's equation be used to predict the VO2max from 1-mile run/walk performance in large numbers of healthy individuals with high VO2max. This research compares the use of 3 different formulae to estimate VO2max from 1-mile run/walk performance in male law enforcement officers aged 20-23 years for the first time and reports the most accurate formula to use when evaluating aerobic capacities of large numbers of healthy individuals.

The Benefits of Exercise Training on Aerobic Capacity in Patients with Heart Failure and Preserved Ejection Fraction.

PubMed

do Prado, Danilo Marcelo Leite; Rocco, Enéas Antônio

2017-01-01

Heart failure with preserved ejection fraction (HFpEF) is defined as an inability of the ventricles to optimally accept blood from atria with blunted end- diastolic volume response by limiting the stroke volume and cardiac output. The HEpEF prevalence is higher in elderly and women and may be associated to hypertension, diabetes mellitus and atrial fibrillation. Severe exercise intolerance, manifested by dyspnea and fatigue during physical effort is the important chronic symptom in HFpEF patients, in which is the major determinant of their reduced quality of life. In this sense, several studies demonstrated reduced aerobic capacity in terms of lower peak oxygen consumption (peak VO 2 ) in patients with HFpEF. In addition, the lower aerobic capacity observed in HFpEF may be due to impaired both convective and diffusive O 2 transport (i.e. reduced cardiac output and arteriovenous oxygen difference, respectively).Exercise training program can help restore physiological function in order to increase aerobic capacity and improve the quality of life in HFpEF patients. Therefore, the primary purpose of this chapter was to clarify the physiological mechanisms associated with reduced aerobic capacity in HFpEF patients. Secondly, special focus was devoted to show how aerobic exercise training can improve aerobic capacity and quality of life in HFpEF patients.

Exercise training in patients with heart disease: review of beneficial effects and clinical recommendations.

PubMed

Gielen, Stephan; Laughlin, M Harold; O'Conner, Christopher; Duncker, Dirk J

2015-01-01

Over the last decades exercise training has evolved into an established evidence-based therapeutic strategy with prognostic benefits in many cardiovascular diseases (CVDs): In stable coronary artery disease (CAD) exercise training attenuates disease progression by beneficially influencing CVD risk factors (i.e., hyperlipidemia, hypertension) and coronary endothelial function. In heart failure (HF) with reduced ejection fraction (HFrEF) training prevents the progressive loss of exercise capacity by antagonizing peripheral skeletal muscle wasting and by promoting left ventricular reverse remodeling with reduction in cardiomegaly and improvement of ejection fraction. Novel areas for exercise training interventions include HF with preserved ejection fraction (HFpEF), pulmonary hypertension, and valvular heart disease. In HFpEF, randomized studies indicate a lusitropic effect of training on left ventricular diastolic function associated with symptomatic improvement of exercise capacity. In pulmonary hypertension, reductions in pulmonary artery pressure were observed following endurance exercise training. Recently, innovative training methods such as high-intensity interval training, resistance training and others have been introduced. Although their prognostic value still needs to be determined, these approaches may achieve superior improvements in aerobic exercise capacity and gain in muscle mass, respectively. In this review, we give an overview of the prognostic and symptomatic benefits of exercise training in the most common cardiac disease entities. Additionally, key guideline recommendations for the initiation of training programs are summarized. Copyright © 2014 Elsevier Inc. All rights reserved.

Obesity impairs skeletal muscle AMPK signaling during exercise: role of AMPKα2 in the regulation of exercise capacity in vivo.

PubMed

Lee-Young, R S; Ayala, J E; Fueger, P T; Mayes, W H; Kang, L; Wasserman, D H

2011-07-01

Skeletal muscle AMP-activated protein kinase (AMPK)α2 activity is impaired in obese, insulin-resistant individuals during exercise. We determined whether this defect contributes to the metabolic dysregulation and reduced exercise capacity observed in the obese state. C57BL/6J wild-type (WT) mice and/or mice expressing a kinase dead AMPKα2 subunit in skeletal muscle (α2-KD) were fed chow or high-fat (HF) diets from 3 to 16 weeks of age. At 15 weeks, mice performed an exercise stress test to determine exercise capacity. In WT mice, muscle glucose uptake and skeletal muscle AMPKα2 activity was assessed in chronically catheterized mice (carotid artery/jugular vein) at 16 weeks. In a separate study, HF-fed WT and α2-KD mice performed 5 weeks of exercise training (from 15 to 20 weeks of age) to test whether AMPKα2 is necessary to restore work tolerance. HF-fed WT mice had reduced exercise tolerance during an exercise stress test, and an attenuation in muscle glucose uptake and AMPKα2 activity during a single bout of exercise (P<0.05 versus chow). In chow-fed α2-KD mice, running speed and time were impaired ∼45 and ∼55%, respectively (P<0.05 versus WT chow); HF feeding further reduced running time ∼25% (P<0.05 versus α2-KD chow). In response to 5 weeks of exercise training, HF-fed WT and α2-KD mice increased maximum running speed ∼35% (P<0.05 versus pre-training) and maintained body weight at pre-training levels, whereas body weight increased in untrained HF WT and α2-KD mice. Exercise training restored running speed to levels seen in healthy, chow-fed mice. HF feeding impairs AMPKα2 activity in skeletal muscle during exercise in vivo. Although this defect directly contributes to reduced exercise capacity, findings in HF-fed α2-KD mice show that AMPKα2-independent mechanisms are also involved. Importantly, α2-KD mice on a HF-fed diet adapt to regular exercise by increasing exercise tolerance, demonstrating that this adaptation is independent of skeletal muscle AMPKα2 activity.

Maintenance of exercise training benefits is associated with adequate milk and dairy products intake in elderly hypertensive subjects following detraining.

PubMed

Moraes, Wilson Max Almeida Monteiro de; Santos, Neucilane Silveira Dos; Aguiar, Larissa Pereira; Sousa, Luís Gustavo Oliveira de

2017-01-01

To investigate whether maintenance of exercise training benefits is associated with adequate milk and dairy products intake in hypertensive elderly subjects after detraining. Twenty-eight elderly hypertensive patients with optimal clinical treatment underwent 16 weeks of multicomponent exercise training program followed by 6 weeks of detraining, and were classified according to milk and dairy products intake as low milk (<3 servings) and high milk (≥3 servings) groups. After exercise training, there was a significant reduction (p<0.001) in body weight, systolic, diastolic and mean blood pressure, an increase in lower and upper limb strength (chair-stand test and elbow flexor test) as well as in aerobic capacity (stationary gait test) and functional capacity (sit down, stand up, and move around the house) in both groups. However, in the Low Milk Intake Group significant changes were observed: body weight (+0.5%), systolic, diastolic and mean blood pressure (+0.9%,+1.4% and +1.1%, respectively), lower extremity strength (-7.0%), aerobic capacity (-3.9%) and functional capacity (+5.4) after detraining. These parameters showed no significant differences between post-detraining and post-training period in High Milk Intake Group. Maintenance of exercise training benefits related to pressure levels, lower extremity strength and aerobic capacity, is associated with adequate milk and dairy products intake in hypertensive elderly subjects following 6 weeks of detraining.

Triiodothyronine, beta-adrenergic receptors, agonist responses, and exercise capacity.

PubMed

Martin, W H

1993-07-01

Although thyroid hormone excess results in increased beta-adrenergic receptor density or agonist responses in some cells of experimental animals, the role of these effects in contributing to clinical manifestations of hyperthyroidism in human subjects is unclear. To shed further light on this issue, we characterized the effect of 2 weeks of excess triiodothyronine administration on cardiac and metabolic responses to graded-dose isoproterenol infusion, skeletal muscle beta-adrenergic receptor density, and physiologic determinants of exercise capacity in young healthy subjects. The slope of the heart rate response to isoproterenol was 36% greater (p < 0.05) after triiodothyronine administration. In addition, beta-adrenergic receptor density was increased (p < 0.01) in all types of skeletal muscle fibers. Maximal oxygen uptake during treadmill exercise declined 5% (p < 0.001) after triiodothyronine administration because of a decrease in the arteriovenous oxygen difference (p < 0.05). The plasma lactate response to submaximal exercise was 25% greater (p < 0.01) in the hyperthyroid state. These effects were paralleled by a decrement in skeletal muscle oxidative capacity and a decrease in cross-sectional area of type 2A skeletal myocytes. Thus, thyroid hormone excess enhances cardiac beta-adrenergic sensitivity under in vivo conditions in human subjects. Nevertheless, exercise capacity is diminished in the hyperthyroid state, an effect that may be related to reduced skeletal muscle oxidative capacity and type 2A fiber atrophy.

A comparison of echocardiographic variables of right ventricular function with exercise capacity after bosentan treatment in patients with pulmonary arterial hypertension: Results from a multicenter, prospective, cohort study.

PubMed

Kim, Hyungseop; Bae Lee, Jin; Park, Jae-Hyeong; Yoo, Byung-Su; Son, Jang-Won; Yang, Dong Heon; Lee, Bong-Ryeol

2017-01-01

Bosentan reduces pulmonary arterial pressure and improves exercise capacity in patients with pulmonary arterial hypertension (PAH). However, there are limited data regarding the extent to which the changes in echocardiographic variables reflect improvements in exercise capacity. We aimed to assess the improvement of echocardiographic variables and exercise capacity after 6 months of bosentan treatment for PAH. We performed a prospective study from June 2012 to June 2015 in seven participating medical centers. Echocardiography, including tissue Doppler imaging (TDI) and the 6-minute walk test distance (6MWD), was performed at baseline and after 6 months of bosentan treatment. We analyzed 19 patients with PAH: seven with congenital shunt, six with collagen vascular disease, and six with idiopathic PAH. After bosentan treatment, mean 6MWD increased by 50 meters. Right ventricle (RV) systolic pressure, tricuspid annular plane systolic excursion, myocardial performance index (MPI) derived from TDI (MPI-TDI) of RV and left ventricle (LV), RV fractional area change, and RV ejection fraction were significantly improved. In particular, the magnitude of RV and LV MPI-TDI showed good correlation with changes in the 6MWD. The magnitude of RV and LV MPI-TDI was strongly associated with improvements in exercise capacity. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:28-34, 2017. © 2016 Wiley Periodicals, Inc.

Dietary nitrate supplementation in COPD: an acute, double-blind, randomized, placebo-controlled, crossover trial.

PubMed

Kerley, Conor P; Cahill, Kathleen; Bolger, Kenneth; McGowan, Aisling; Burke, Conor; Faul, John; Cormican, Liam

2015-01-30

The acute consumption of dietary nitrate has been shown to improve exercise capacity in athletes, healthy adults and subjects with peripheral vascular disease. Many COPD patients have reduced exercise capacity. We hypothesized that acute nitrate consumption might increase incremental shuttle walk test (ISWT) distance in COPD subjects. Eleven COPD subjects were randomly assigned to consume either a high nitrate or a matched, low nitrate beverage in a double-blind, randomized, placebo-controlled, crossover design. ISWT distance was measured both before and 3 h after the beverage and change was recorded. After a 7-day washout, ISWT distances were re-measured before and 3 h after the alternate beverage and changes were recorded. We observed an increase in ISWT distance after consuming the high nitrate juice (25 m) compared with a reduction after the low nitrate juice (14 m) (p < 0.01). This improvement in exercise capacity was associated with significant increases in serum nitrate (p < 0.000005) and nitrite (p < 0.01) levels and a significant lowering of resting blood pressure (<0.05). In patients with stable COPD, the acute consumption of dietary nitrate increased serum nitrate/nitrite levels and exercise capacity and was associated with a decrease in resting blood pressure. Nitrate consumption might alter exercise capacity in COPD patients. Copyright © 2014 Elsevier Inc. All rights reserved.

Exercise Capacity Assessment by the Modified Shuttle Walk Test and its Correlation with Biochemical Parameters in Obese Children and Adolescents.

PubMed

de Assumpção, Priscila Kurz; Heinzmann-Filho, João Paulo; Isaia, Heloisa Ataíde; Holzschuh, Flávia; Dalcul, Tiéle; Donadio, Márcio Vinícius Fagundes

2018-03-23

To evaluate exercise capacity of obese children and adolescents compared with normal-weight individuals and to investigate possible correlations with blood biochemical parameters. In this study, children and adolescents between 6 and 18 y were included and divided into control (eutrophic) and obese groups according to body mass index (BMI). Data were collected regarding demographic, anthropometric, waist circumference and exercise capacity through the Modified Shuttle Walk Test (MSWT). In the obese group, biochemical parameters in the blood (total cholesterol, HDL, LDL, triglycerides and glucose) were evaluated, and a physical activity questionnaire was applied. Seventy seven participants were included; 27 in the control group and 50 obese. There was no significant difference between the two groups regarding sample characteristics, except for body weight, BMI and waist circumference. Most obese children presented results of biochemical tests within the desirable limit, though none were considered active. There was a significant exercise capacity reduction (p < 0.001) in the obese group compared to control subjects. Positive correlations were identified for the MSWT with age and height, and a negative correlation with BMI. However, there were no correlations with the biochemical parameters analyzed. Obese children and adolescents have reduced exercise capacity when compared to normal individuals. The MSWT performance seems to have a negative association with BMI, but is not correlated with blood biochemical parameters.

Inhaled fentanyl citrate improves exercise endurance during high-intensity constant work rate cycle exercise in chronic obstructive pulmonary disease.

PubMed

Jensen, Dennis; Alsuhail, Abdullah; Viola, Raymond; Dudgeon, Deborah J; Webb, Katherine A; O'Donnell, Denis E

2012-04-01

Activity limitation and dyspnea are the dominant symptoms of chronic obstructive pulmonary disease (COPD). Traditionally, efforts to alleviate these symptoms have focused on improving ventilatory mechanics, reducing ventilatory demand, or both of these in combination. Nevertheless, many patients with COPD remain incapacitated by dyspnea and exercise intolerance despite optimal therapy. To determine the effect of single-dose inhalation of nebulized fentanyl citrate (a μ-opioid agonist drug) on exercise tolerance and dyspnea in COPD. In a randomized, double-blind, placebo-controlled, crossover study, 12 stable patients with COPD (mean ± standard error of the mean post-β(2)-agonist forced expiratory volume in one second [FEV(1)] and FEV(1) to forced vital capacity ratio of 69% ± 4% predicted and 49% ± 3%, respectively) received either nebulized fentanyl citrate (50 mcg) or placebo on two separate days. After each treatment, patients performed pulmonary function tests and a symptom-limited constant work rate cycle exercise test at 75% of their maximum incremental work rate. There were no significant postdose differences in spirometric parameters or plethysmographic lung volumes. Neither the intensity nor the unpleasantness of perceived dyspnea was, on average, significantly different at isotime (5.0 ± 0.6 minutes) or at peak exercise after treatment with fentanyl citrate vs. placebo. Compared with placebo, fentanyl citrate was associated with 1) increased exercise endurance time by 1.30 ± 0.43 minutes or 25% ± 8% (P=0.01); 2) small but consistent increases in dynamic inspiratory capacity by ∼0.10 L at isotime and at peak exercise (both P≤0.03); and 3) no concomitant change in ventilatory demand, breathing pattern, pulmonary gas exchange, and/or cardiometabolic function during exercise. The mean rate of increase in dyspnea intensity (1.2 ± 0.3 vs. 2.9 ± 0.8 Borg units/minute, P=0.03) and unpleasantness ratings (0.5 ± 0.2 vs. 2.9 ± 1.3 Borg units/minute, P=0.06) between isotime and peak exercise was less after treatment with fentanyl citrate vs. placebo. Single-dose inhalation of fentanyl citrate was associated with significant and potentially clinically important improvements in exercise tolerance in COPD. These improvements were accompanied by a delay in the onset of intolerable dyspnea during exercise near the limits of tolerance. Copyright © 2012 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

The Link between Reduced Inspiratory Capacity and Exercise Intolerance in Chronic Obstructive Pulmonary Disease.

PubMed

O'Donnell, Denis E; Elbehairy, Amany F; Webb, Katherine A; Neder, J Alberto

2017-07-01

Low inspiratory capacity (IC), chronic dyspnea, and reduced exercise capacity are inextricably linked and are independent predictors of increased mortality in chronic obstructive pulmonary disease. It is no surprise, therefore, that a major goal of management is to improve IC by reducing lung hyperinflation to improve respiratory symptoms and health-related quality of life. The negative effects of lung hyperinflation on respiratory muscle and cardiocirculatory function during exercise are now well established. Moreover, there is growing appreciation that a key mechanism of exertional dyspnea in chronic obstructive pulmonary disease is critical mechanical constraints on tidal volume expansion during exercise when resting IC is reduced. Further evidence for the importance of lung hyperinflation comes from multiple studies, which have reported the clinical benefits of therapeutic interventions that reduce lung hyperinflation and increase IC. A reduced IC in obstructive pulmonary disease is further eroded by exercise and contributes to ventilatory limitation and dyspnea. It is an important outcome for both clinical and research studies.

Comparing exercise responses to aerobic plus resistance training between postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy and healthy women.

PubMed

Paulo, Thais R S de; Winters-Stone, Kerri M; Viezel, Juliana; Rossi, Fabricio E; Aro, Bruna L; Trindade, Ana Carolina A C; Codogno, Jamile S; Freitas Junior, Ismael F

2018-04-12

The aim of this study was to explore whether postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy differ from healthy postmenopausal women in their response to the same aerobic + resistance training. The participants were separated into two groups: postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy for an average of 20 months (18 women) and healthy postmenopausal women (24 women). We assessed aerobic capacity (predicted maximum oxygen uptake (VO 2 max) and maximum running velocity test (Vmax)) through a walking test, upper and lower body muscle strength using an estimated one-repetition maximum test, and body composition by dual-energy X-ray absorptiometry at baseline and at three, six, and nine months, respectively. The exercise program was performed three times/week over nine months and consisted of 40 min of machine-based strength training (seated cable row, bench press, leg extension, leg press, and leg curl, as well as bridge, abdominal, and standard plank exercises) followed by 30 min of treadmill walking. Analysis of variance (ANOVA) with repeated measures was used to compare the groups over time. Postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy and healthy postmenopausal women presented similar improvements in estimated lower body strength, predicted VO 2max and V max , and body fat mass. For maximal upper body strength, there was a significant group x time interaction after six months of training (p = 0.01). The healthy postmenopausal women presented a significant increase in upper body strength after six months, while postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy demonstrated an improvement only at nine months of training. The breast cancer survivors undergoing aromatase inhibitor therapy presented increased lean mass while healthy postmenopausal women maintained values over time (Breast cancer: 33.7 ± 3.9(Pre) vs. 34.1 ± 3.4 kg (Post) and healthy women: 36.4 ± 5.1 (Pre) vs. 36.4 ± 5.0 kg (Post), p = 0.004). Our findings suggest that postmenopausal women undergoing aromatase inhibitor therapy for breast cancer demonstrated adaptations and similar trainability to the same regimen of resistance + aerobic training as healthy postmenopausal women. Implications for Rehabilitation Combined exercise program (aerobic plus resistance) is an important non-pharmacological strategies to improve strength, aerobic capacity, and body composition in breast cancer survivors undergoing aromatase inhibitor therapy. Furthermore, it is important to highlight that the time of intervention seems to influence the upper body strength response in this population. This study showed that trainers and other specialists do not need to modify the prescription of exercise related to healthy women, since the combined exercise program induced similar benefits in strength, aerobic capacity, and body composition in postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy and healthy postmenopausal women.

Enzymatic capacities of skeletal muscle - Effects of different types of training

NASA Technical Reports Server (NTRS)

Booth, F. W.; Hugman, G. R.

1981-01-01

Long-term adaptation mechanisms to maintain homeostasis at increased levels of exertion such as those caused by regular exercise are described. Mitochondrial changes have been found to be a result of endurance exercises, while mitochondrial responses to other types of exercise are small. Further discussion is devoted to long-term changes in glucose transport, hexokinase, phosphofructokinase, pyruvate kinase, and the increased sensitivity of an endurance trained muscle to insulin. Less lactate has been found to be produced by the skeletal muscles at the same work rate after adaptation to endurance exercise training, and the capacity for the flux of the two-carbon acetyl chain through the citric acid cycle increases in skeletal muscles in response to endurance training. Finally, endurance training is noted to result in glycogen sparing and an increase in the capacity to utilize fatty acids.

Relation between lung function, exercise capacity, and exposure to asbestos cement.

PubMed Central

Wollmer, P; Eriksson, L; Jonson, B; Jakobsson, K; Albin, M; Skerfving, S; Welinder, H

1987-01-01

A group of 137 male workers with known exposure (mean 20 fibre years per millilitre) to asbestos cement who had symptoms or signs of pulmonary disease was studied together with a reference group of 49 healthy industrial workers with no exposure to asbestos. Lung function measurements were made at rest and during exercise. Evidence of lung fibrosis was found as well as of obstructive airways disease in the exposed group compared with the reference group. Asbestos cement exposure was related to variables reflecting lung fibrosis but not to variables reflecting airflow obstruction. Smoking was related to variables reflecting obstructive lung disease. Exercise capacity was reduced in the exposed workers and was related to smoking and to lung function variables, reflecting obstructive airways disease. There was no significant correlation between exercise capacity and exposure to asbestos cement. PMID:3651353

Black tea high-molecular-weight polyphenol stimulates exercise training-induced improvement of endurance capacity in mouse via the link between AMPK and GLUT4.

PubMed

Eguchi, Tomoaki; Kumagai, Chiaki; Fujihara, Takashi; Takemasa, Thoru; Ozawa, Tetsuo; Numata, Osamu

2013-01-01

Aerobic exercise can promote "fast-to-slow transition" in skeletal muscles, i.e. an increase in oxidative fibers, mitochondria, and myoglobin and improvement in glucose and lipid metabolism. Here, we found that mice administered Mitochondria Activation Factor (MAF) combined with exercise training could run longer distances and for a longer time compared with the exercise only group; MAF is a high-molecular-weight polyphenol purified from black tea. Furthermore, MAF intake combined with exercise training increased phosphorylation of AMPK and mRNA level of glucose transporter 4 (GLUT4). Thus, our data demonstrate for the first time that MAF activates exercise training-induced intracellular signaling pathways that involve AMPK, and improves endurance capacity.

The measurement of energy consumption by exercise bikes

NASA Astrophysics Data System (ADS)

Jwo, Ching-Song; Chien, Chao-Chun; Jeng, Lung-Yue

2006-11-01

This paper is intended as an investigation is that to measure the amount of energy consumption can be consumed by riding bikes and also could recycle the consuming energy during exercising. Exercisers ride the bicycle inputting the driving force through a compressor of refrigeration system, which can circulate the refrigerant in the system and calculate the calorific capacity from the spread of the condenser. In addition, we can make up chiller water in the evaporator. Experiments were performed to prove the hypotheses. Therefore, this experiment has designed the sports goods which reach the purpose of doing exercise, measuring accurately the consuming calorific capacity and having the function of making chiller water. After exercising, you can drink the water producing during exercise and apply on the system of air conditioner, which attains two objectives.

Lung volumes identify an at-risk group in persons with prolonged secondhand tobacco smoke exposure but without overt airflow obstruction.

PubMed

Arjomandi, Mehrdad; Zeng, Siyang; Geerts, Jeroen; Stiner, Rachel K; Bos, Bruce; van Koeverden, Ian; Keene, Jason; Elicker, Brett; Blanc, Paul D; Gold, Warren M

2018-01-01

Exposure to secondhand smoke (SHS) is associated with occult obstructive lung disease as evident by abnormal airflow indices representing small airway disease despite having preserved spirometry (normal forced expiratory volume in 1 s-to-forced vital capacity ratio, FEV 1 /FVC). The significance of lung volumes that reflect air trapping in the presence of preserved spirometry is unclear. To investigate whether lung volumes representing air trapping could determine susceptibility to respiratory morbidity in people with SHS exposure but without spirometric chronic obstructive pulmonary disease, we examined a cohort of 256 subjects with prolonged occupational SHS exposure and preserved spirometry. We elicited symptom prevalence by structured questionnaires, examined functional capacity (maximum oxygen uptake, VO 2max ) by exercise testing, and estimated associations of those outcomes with air trapping (plethysmography-measured residual volume-to-total lung capacity ratio, RV/TLC), and progressive air trapping with exertion (increase in fraction of tidal breathing that is flow limited on expiration during exercise (per cent of expiratory flow limitation, %EFL)). RV/TLC was within the predicted normal limits, but was highly variable spanning 22%±13% and 16%±8% across the increments of FEV 1 /FVC and FEV 1 , respectively. Respiratory complaints were prevalent (50.4%) with the most common symptom being ≥2 episodes of cough per year (44.5%). Higher RV/TLC was associated with higher OR of reporting respiratory symptoms (n=256; r 2 =0.03; p=0.011) and lower VO 2max (n=179; r 2 =0.47; p=0.013), and %EFL was negatively associated with VO 2max (n=32; r 2 =0.40; p=0.017). In those at risk for obstruction due to SHS exposure but with preserved spirometry, higher RV/TLC identifies a subgroup with increased respiratory symptoms and lower exercise capacity.

Left atrial mechanics strongly predict functional capacity assessed by cardiopulmonary exercise testing in subjects without structural heart disease.

PubMed

Leite, Luís; Mendes, Sofia Lázaro; Baptista, Rui; Teixeira, Rogério; Oliveira-Santos, Manuel; Ribeiro, Nelson; Coutinho, Rosa; Monteiro, Victor; Martins, Rui; Castro, Graça; Ferreira, Maria João; Pego, Mariano

2017-05-01

Left atrium function is essential for cardiovascular performance and is evaluable by two-dimensional speckle-tracking echocardiography (2D-STE). Our aim was to determine how echocardiographic parameters interrelate with exercise capacity and ventilatory efficiency in subjects with no structural heart disease. Asymptomatic volunteers, in sinus rhythm and with normal biventricular size and function, were recruited from a community-based population. Individuals with moderate-to-severe valvular disease, pulmonary hypertension, and history of cardiac disease were excluded. We performed a transthoracic echocardiogram and assessed left atrial (LA) and left ventricular (LV) mechanics via 2D-STE. Cardiopulmonary exercise testing by treadmill took place immediately thereafter. Peak oxygen uptake (VO 2 ) served as measure of functional capacity and ventilation/carbon dioxide output (VE/VCO 2 ) slope as surrogate of ventilation/perfusion mismatch. 20 subjects were included (age 51 ± 14 years, male gender 65%). Peak VO 2 strongly correlated with age (r = -0.83; P < 0.01), with E/e' ratio (r = -0.72; P < 0.01), and with LA reservoir- and conduit-phase mechanics, particularly with LA conduit strain rate (SR) (r = -0.82; P < 0.01), but showed no correlation with LA volume index or LV mechanics. A similar pattern of associations was identified for VE/VCO 2 slope. In multivariate analysis, LA conduit SR (β = -0.69; P = 0.02) emerged as sole independent correlate of peak VO 2 , adjusted for age and for E/e' ratio (adjusted r 2  = 0.76; P < 0.01). Conduit and reservoir components of LA mechanics displayed strong associations with peak VO 2 and VE/VCO 2 slope. LA conduit-phase SR seems best suited as echocardiographic marker of functional capacity in subjects with no structural heart disease.

Study of the relationship between the aerobic capacity (VO2 max) and the rating of perceived exertion based on the measurement of heart beat in the metal industries Esfahan

PubMed Central

Habibi, Ehsanollah; Dehghan, Habibollah; Moghiseh, Mohammad; Hasanzadeh, Akbar

2014-01-01

Background and Objective: To establish a balance between work (physical exercise) and human beings, the aerobic capacity (VO2 max) could be used as a measure. Additionally, the subjective and physiological assessment could be applied as one of the methods for assessing physical exercise. The most commonly used tools for the assessment of fatigue during physical exercise include the Borg scale Rating of perceived Exertion (RPE) in relation to subjective symptoms and heart rate (HR) in relation to physiological symptoms. The study is aimed to investigate the relationship between the aerobic capacity and the RPE based on the measurement of heat rate (HR) of workers from the Metal Industries of Isfahan. Materials and Methods: The subjects were 200 male workers from metal components manufacturers in Isfahan selected by using random sampling based on statistic method. The subjects were examined by using ergometer in accordance with A strand 6 minutes cycle test protocol. Furthermore, the subjects were asked to rate their status based on the Borg rating scale at the end of each minute. Additionally, their heat rates were monitored and recorded automatically at the end of each minutes. Results: Statistical analysis showed that there was a significant relationship between the RPE and the aerobic capacity (VO2 max) (r = –0.904, P < 0.05). The results illustrated that there was a stronger correlation between HR and VO2 max (r = 0.991, P < 0.001). The regression analysis of the quadratic equation also indicated that there was also a significant relationship between the VO2 max and HR. Conclusions: The results indicated that there was a strong relationship between the RPE and VO2 max, as well as a greater correlation between HR and VO2 max. Therefore, the HR could be used as a Prediction measure to estimate VO2 max. PMID:25077148

Effects of combined exercise training and electromyostimulation treatments in chronic heart failure: A prospective multicentre study.

PubMed

Iliou, Marie C; Vergès-Patois, Bénédicte; Pavy, Bruno; Charles-Nelson, Anais; Monpère, Catherine; Richard, Rudy; Verdier, Jean C

2017-08-01

Background Exercise training as part of a comprehensive cardiac rehabilitation is recommended for patients with cardiac heart failure. It is a valuable method for the improvement of exercise tolerance. Some studies reported a similar improvement with quadricipital electrical myostimulation, but the effect of combined exercise training and electrical myostimulation in cardiac heart failure has not been yet evaluated in a large prospective multicentre study. Purpose The aim of this study was to determine whether the addition of low frequency electrical myostimulation to exercise training may improve exercise capacity and/or muscular strength in cardiac heart failure patients. Methods Ninety-one patients were included (mean age: 58 ± 9 years; New York Heart Association II/III: 52/48%, left ventricular ejection fraction: 30 ± 7%) in a prospective French study. The patients were randomised into two groups: 41 patients in exercise training and 50 in exercise training + electrical myostimulation. All patients underwent 20 exercise training sessions. In addition, in the exercise training + electrical myostimulation group, patients underwent 20 low frequency (10 Hz) quadricipital electrical myostimulation sessions. Each patient underwent a cardiopulmonary exercise test, a six-minute walk test, a muscular function evaluation and a quality of life questionnaire, before and at the end of the study. Results A significant improvement of exercise capacity (Δ peak oxygen uptake+15% in exercise training group and +14% in exercise training + electrical myostimulation group) and of quality of life was observed in both groups without statistically significant differences between the two groups. Mean creatine kinase level increased in the exercise training group whereas it remained stable in the combined group. Conclusions This prospective multicentre study shows that electrical myostimulation on top of exercise training does not demonstrate any significant additional improvement in exercise capacity in cardiac heart failure patients.

Impact of a brief exercise program on the physical and psychosocial health of prostate cancer survivors: A pilot study.

PubMed

Skinner, Tina L; Peeters, Gmme Geeske; Croci, Ilaria; Bell, Katherine R; Burton, Nicola W; Chambers, Suzanne K; Bolam, Kate A

2016-09-01

It is well established that exercise is beneficial for prostate cancer survivors. The challenge for health professionals is to create effective strategies to encourage survivors to exercise in the community. Many community exercise programs are brief in duration (e.g. <5 exercise sessions); whilst evidence for the efficacy of exercise within the literature are derived from exercise programs ≥8 weeks in duration, it is unknown if health benefits can be obtained from a shorter program. This study examined the effect of a four-session individualized and supervised exercise program on the physical and psychosocial health of prostate cancer survivors. Fifty-one prostate cancer survivors (mean age 69±7 years) were prescribed 1 h, individualized, supervised exercise sessions once weekly for 4 weeks. Participants were encouraged to increase their physical activity levels outside of the exercise sessions. Objective measures of muscular strength, exercise capacity, physical function and flexibility; and self-reported general, disease-specific and psychosocial health were assessed at baseline and following the intervention. Improvements were observed in muscle strength (leg press 17.6 percent; P < 0.001), exercise capacity (400-m walk 9.3 percent; P < 0.001), physical function (repeated chair stands 20.1 percent, usual gait speed 19.3 percent, timed up-and-go 15.0 percent; P < 0.001), flexibility (chair sit and reach +2.9 cm; P < 0.001) and positive well-being (P = 0.014) following the exercise program. A four-session exercise program significantly improved the muscular strength, exercise capacity, physical function and positive well-being of prostate cancer survivors. This short-duration exercise program is safe and feasible for prostate cancer survivors and a randomized controlled trial is now required to determine whether a similar individualized exercise regimen improves physical health and mental well-being over the short, medium and long term. © 2016 John Wiley & Sons Australia, Ltd.

[Results of a physical therapy program in nursing home residents: A randomized clinical trial].

PubMed

Casilda-López, Jesús; Torres-Sánchez, Irene; Garzón-Moreno, Victor Manuel; Cabrera-Martos, Irene; Valenza, Marie Carmen

2015-01-01

The maintenance of the physical functionality is a key factor in the care of the elderly. Inactive people have a higher risk of death due to diseases associated with inactivity. In addition, the maintenance of optimal levels of physical and mental activity has been suggested as a protective factor against the development and progression of chronic illnesses and disability. The objective of this study is to assess the effectiveness of an 8-week exercise program with elastic bands, on exercise capacity, walking and balance in nursing home residents. A nursing home sample was divided into two groups, intervention group (n=26) and control group (n=25). The intervention group was included in an 8-week physical activity program using elastic bands, twice a week, while the control group was took part in a walking programme. Outcome measurements were descriptive variables (anthropometric characteristics, quality of life, fatigue, fear of movement) and fundamental variables (exercise capacity, walking and balance). A significant improvement in balance and walking speed was observed after the programme. Additionally, exercise capacity improved significantly (P≤.001), and the patients showed an improvement in perceived dyspnea after the physical activity programme in the intervention group. The exercise program was safe and effective in improving dyspnea, exercise capacity, walking, and balance in elderly. Copyright © 2014 SEGG. Published by Elsevier Espana. All rights reserved.

Low-level carbon monoxide exposure and work capacity at 1600 meters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weiser, P.C.; Cropp, G.J.A.; Morrill, C.G.

At sea level, low-level carbon monoxide (CO) exposure impairs exercise performance. To determine if altitude residence at 1600 m augments this CO effect, two studies of graded treadmill work capacity were done. The Initial Study investigated nine, non-smoking male subjects breathing either filtered air (FA) or 28 ppm CO in filtered air. End-exercise carboxyhemoglobin (HbCO) levels averaged 0.9 %HbCO breathing FA and 4.7 %HbCO breathing CO. Total work performance and aerobic work capacity were reduced. Work heart rate was elevated, and post-exercise left ventricular ejection time breathing CO did not shorten to the same degree as with FA exposure. COmore » exposure resulted in a lower anaerobic threshold, and a greater minute ventilation occurred at work rates heavier than the anaerobic threshold due to an increased blood lactate level. The Dose-Response Study exposed twelve subjects to FA or CO such that the end-exercise HbCO levels were 0.7, 3.5, 5.4 and 8.7 %HbCO. Exercise performance and aerobic work capacity were impaired in proportion to the CO exposure. In both studies, maximal cardio-pulmonary responses were not different, but submaximal exercise changes were elevated breathing CO. Thus, in healthy young men residing near 1600 m, an increase in low-level CO exposure produced a linear decrement in maximal aerobic performance similar to that reported at sea level.« less

Intrinsic aerobic capacity sets a divide for aging and longevity

PubMed Central

Koch, Lauren Gerard; Kemi, Ole J.; Qi, Nathan; Leng, Sean X.; Bijma, Piter; Gilligan, Lori J.; Wilkinson, John E.; Wisløff, Helene; Høydal, Morten A.; Rolim, Natale; Abadir, Peter M.; Van Grevenhof, Ilse; Smith, Godfrey L.; Burant, Charles F.; Ellingsen, Øyvind; Britton, Steven L.; Wisløff, Ulrik

2011-01-01

Rationale Low aerobic exercise capacity is a powerful predictor of premature morbidity and mortality for healthy adults as well as those with cardiovascular disease For aged populations, poor performance on treadmill or extended walking tests indicates closer proximity to future health declines. Together, these findings suggest a fundamental connection between aerobic capacity and longevity. Objectives Through artificial selective breeding, we developed an animal model system to prospectively test the association between aerobic exercise capacity and survivability (aerobic hypothesis). Methods and Results Laboratory rats of widely diverse genetic backgrounds (N:NIH stock) were selectively bred for low or high intrinsic (inborn) treadmill running capacity. Cohorts of male and female rats from generations 14, 15 and 17 of selection were followed for survivability and assessed for age-related declines in cardiovascular fitness including maximal oxygen uptake (VO2max), myocardial function, endurance performance, and change in body mass. Median lifespan for low exercise capacity rats was 28-45% shorter than high capacity rats (hazard ratio, 0.06; P<.001). VO2max, measured across adulthood was a reliable predictor of lifespan (P<.001). During progression from adult to old age, left ventricular myocardial and cardiomyocyte morphology, contractility, and intracellular Ca2+ handling in both systole and diastole, as well as mean blood pressure, were more compromised in rats bred for low aerobic capacity. Physical activity levels, energy expenditure (VO2), and lean body mass were all better sustained with age in rats bred for high aerobic capacity. Conclusions These data obtained from a contrasting heterogeneous model system provide strong evidence that genetic segregation for aerobic exercise capacity can be linked with longevity and useful for deeper mechanistic exploration. PMID:21921265

Intrinsic aerobic capacity sets a divide for aging and longevity.

PubMed

Koch, Lauren Gerard; Kemi, Ole J; Qi, Nathan; Leng, Sean X; Bijma, Piter; Gilligan, Lori J; Wilkinson, John E; Wisløff, Helene; Høydal, Morten A; Rolim, Natale; Abadir, Peter M; van Grevenhof, Elizabeth M; Smith, Godfrey L; Burant, Charles F; Ellingsen, Oyvind; Britton, Steven L; Wisløff, Ulrik

2011-10-28

Low aerobic exercise capacity is a powerful predictor of premature morbidity and mortality for healthy adults as well as those with cardiovascular disease. For aged populations, poor performance on treadmill or extended walking tests indicates closer proximity to future health declines. Together, these findings suggest a fundamental connection between aerobic capacity and longevity. Through artificial selective breeding, we developed an animal model system to prospectively test the association between aerobic exercise capacity and survivability (aerobic hypothesis). Laboratory rats of widely diverse genetic backgrounds (N:NIH stock) were selectively bred for low or high intrinsic (inborn) treadmill running capacity. Cohorts of male and female rats from generations 14, 15, and 17 of selection were followed for survivability and assessed for age-related declines in cardiovascular fitness including maximal oxygen uptake (VO(2max)), myocardial function, endurance performance, and change in body mass. Median lifespan for low exercise capacity rats was 28% to 45% shorter than high capacity rats (hazard ratio, 0.06; P<0.001). VO(2max), measured across adulthood was a reliable predictor of lifespan (P<0.001). During progression from adult to old age, left ventricular myocardial and cardiomyocyte morphology, contractility, and intracellular Ca(2+) handling in both systole and diastole, as well as mean blood pressure, were more compromised in rats bred for low aerobic capacity. Physical activity levels, energy expenditure (Vo(2)), and lean body mass were all better sustained with age in rats bred for high aerobic capacity. These data obtained from a contrasting heterogeneous model system provide strong evidence that genetic segregation for aerobic exercise capacity can be linked with longevity and are useful for deeper mechanistic exploration of aging.

Acute exhaustive rowing exercise reduces skin microvascular dilator function in young adult rowing athletes.

PubMed

Stupin, Marko; Stupin, Ana; Rasic, Lidija; Cosic, Anita; Kolar, Luka; Seric, Vatroslav; Lenasi, Helena; Izakovic, Kresimir; Drenjancevic, Ines

2018-02-01

The effect of acute exhaustive exercise session on skin microvascular reactivity was assessed in professional rowers and sedentary subjects. A potential involvement of altered hemodynamic parameters and/or oxidative stress level in the regulation of skin microvascular blood flow by acute exercise were determined. Anthropometric, biochemical, and hemodynamic parameters were measured in 18 young healthy sedentary men and 20 professional rowers who underwent a single acute exercise session. Post-occlusive reactive hyperemia (PORH), endothelium-dependent acetylcholine (ACh), and endothelium-independent sodium nitroprusside (SNP) microvascular responses were assessed by laser Doppler flowmetry in skin microcirculation before and after acute exercise. Serum lipid peroxidation products and plasma antioxidant capacity were measured using spectrophotometry. At baseline, rowers had significantly lower diastolic blood pressure (DBP) and heart rate (HR), and higher stroke volume (SV), PORH, and endothelium-dependent vasodilation than sedentary. Acute exercise caused a significant increase in systolic blood pressure, DBP, HR, and SV and a decrease in total peripheral resistance in both groups. Acute exercise induced a significant impairment in PORH and ACh-induced response in rowers, but not in sedentary, whereas the SNP-induced vasodilation was not affected by acute exercise in any group. Antioxidant capacity significantly increased only in sedentary after acute exercise. Single acute exercise session impaired microvascular reactivity and endothelial function in rowers but not in sedentary, possibly due to (1) more rowing grades and higher exercise intensity achieved by rowers; (2) a higher increase in arterial pressure in rowers than in sedentary men; and (3) a lower antioxidant capacity in rowers.

Effects of a renal rehabilitation exercise program in patients with CKD: a randomized, controlled trial.

PubMed

Rossi, Ana P; Burris, Debra D; Lucas, F Leslie; Crocker, Gail A; Wasserman, James C

2014-12-05

Patients with CKD have a high prevalence of cardiovascular disease associated with or exacerbated by inactivity. This randomized, controlled study investigated whether a renal rehabilitation exercise program for patients with stages 3 or 4 CKD would improve their physical function and quality of life. In total, 119 adults with CKD stages 3 and 4 were randomized, and 107 of these patients proceeded to usual care or the renal rehabilitation exercise intervention consisting of usual care plus guided exercise two times per week for 12 weeks (24 sessions). Physical function was determined by three well established performance-based tests: 6-minute walk test, sit-to-stand test, and gait-speed test. Health-related quality of life was assessed by the RAND 36-Item Short Form Health Survey. At baseline, no differences in self-reported level of activity, 6-minute walk test, and sit-to-stand test scores were observed between the usual care (n=48) and renal rehabilitation exercise (n=59) groups, although baseline gait-speed test score was higher in the renal rehabilitation exercise group (P<0.001). At follow-up, the renal rehabilitation exercise group but not the usual care group showed significant improvements in the 6-minute walk test (+210.4±266.0 ft [19% improvement] versus -10±219.9 ft; P<0.001), the sit-to-stand test (+26.9±27% of age prediction [29% improvement] versus +0.7±12.1% of age prediction; P<0.001), and the RAND-36 physical measures of role functioning (P<0.01), physical functioning (P<0.01), energy/fatigue levels (P=0.01), and general health (P=0.03) and mental measure of pain scale (P=0.04). The renal rehabilitation exercise regimen was generally well tolerated. A 12-week/24-session renal rehabilitation exercise program improved physical capacity and quality of life in patients with CKD stages 3 and 4. Longer follow-up is needed to determine if these findings will translate into decreased mortality rates. Copyright © 2014 by the American Society of Nephrology.

The effects of exercise-based rehabilitation on balance and gait for stroke patients: a systematic review.

PubMed

An, Minjeong; Shaughnessy, Marianne

2011-12-01

This review evaluated the effects of balance and/or gait exercise interventions for stroke survivors and summarized the available evidence on these exercise interventions. A search for studies published between January 2001 and January 2010 was performed using the keywords stroke, walking or balance, and physical activity or exercise. Seventeen randomized clinical trials were identified. The findings suggest that initiating early rehabilitation during acute to subacute stroke recovery can improve balance and walking capacity. The findings also demonstrate that at least 1 hour, three to five times per week, of balance training and 30 minutes, three to five times per week, of gait-oriented exercise are effective to improve balance and walking. This review confirms that balance and walking capacity are improved with specific exercise modalities. A combination of balance, gait, and aerobic exercises would be ideal.

Selectively bred rat model system for low and high response to exercise training

PubMed Central

Pollott, Geoffrey E.; Britton, Steven L.

2013-01-01

We initiated a large-scale bidirectional selection experiment in a genetically heterogeneous rat population (N/NIH stock, n = 152) to develop lines of low response trainers (LRT) and high response trainers (HRT) as a contrasting animal model system. Maximal treadmill running distance [meters (m)] was tested before (DIST1) and after (DIST2) standardized aerobic treadmill training over an 8 wk period (3 exercise sessions per week). Response to training was calculated as the change in exercise capacity (ΔDIST = DIST2 − DIST1). A within-family selection and rotational breeding paradigm between 10 families was practiced for both selected lines. For the founder population, exercise training produced a 140 ± 15 m gain in exercise capacity with interindividual variation ranging from −339 to +627 m. After 15 generations of selection (n = 3,114 rats), HRT rats improved 223 ± 20 m as a result of exercise training while exercise capacity declined −65 ± 15 m in LRT rats given the same absolute training environment. The narrow-sense heritability (h2) for ΔDIST was 0.10 ± 0.02. The LRT and HRT lines did not differ significantly for body weight or intrinsic (i.e., DIST1) exercise capacity. Using pedigree records the inbreeding coefficient increased at a rate of 1.7% per generation for HRT and 1.6% per generation for LRT, ∼30% slower than expected from random mating. Animal models developed from heterogeneous stock and enriched via selection, as presented here, often generate extreme values for traits of interest and may prove more useful than current models for uncovering genetic underpinnings. PMID:23715262

Exercise-based cardiac rehabilitation in patients with heart failure: a meta-analysis of randomised controlled trials between 1999 and 2013.

PubMed

Lewinter, Christian; Doherty, Patrick; Gale, Christopher P; Crouch, Simon; Stirk, Lisa; Lewin, Robert J; LeWinter, Martin M; Ades, Philip A; Køber, Lars; Bland, John M

2015-12-01

Guidelines recommend exercise-based cardiac rehabilitation (EBCR) for patients with heart failure (HF). However, established research has not investigated the longer-term outcomes including mortality and hospitalisation in light of the contemporary management of HF. This was a systematic review including a meta-analysis of EBCR on all-cause mortality, hospital admission, and standardised exercise capacity using four separate exercise tests in patients with heart failure over a minimum follow-up of six months from January 1999-January 2013. Electronic searches were performed in the databases: Medline, CENTRAL, EMBASE, CINAHL, and PsycINFO constrained to randomised controlled trials (RCTs). A total of 46 separate RCTs qualified for the meta-analysis, which employed conventional methods for binary and continuous data. The relative risk (RR) ratio for hospital admission (12 studies) was significantly reduced (RR ratio 0.65; 95% confidence interval (CI) 0.50-0.84; p = 0.001), but mortality (21 studies) was not (RR ratio 0.88; 95% CI 0.77-1.02; p = 0.08). The standardised exercise capacity (26 studies) showed a standardised mean difference (SMD) in favour of the exercise group as compared with the controls (SMD 0.98, 95% CI 0.59-1.37; p < 0.001). Women and elderly people were less frequently enrolled in the RCTs independent of the outcomes. Heterogeneity was moderate to high in the analysis of hospital admission and the standardised exercise capacity demonstrated through skewedness in their funnel plots. EBCR in patients with HF is associated with significant improvements in exercise capacity and hospital admission over a minimum of six months follow-up, but not in all-cause mortality. © The European Society of Cardiology 2014.

The influence of age, gender, and training on exercise efficiency.

PubMed

Woo, J Susie; Derleth, Christina; Stratton, John R; Levy, Wayne C

2006-03-07

The aim of this study was to determine whether changes in oxygen efficiency occur with aging or exercise training in healthy young and older subjects. Exercise capacity declines with age and improves with exercise training. Whether changes in oxygen efficiency, defined as the oxygen cost per unit work, contributes to the effects of aging or training has not yet been defined. Sixty-one healthy subjects were recruited into four groups of younger women (ages 20 to 33 years, n = 15), younger men (ages 20 to 30 years, n = 12), older women (ages 65 to 79 years, n = 16), and older men (ages 65 to 77 years, n = 18). All subjects underwent cardiopulmonary exercise testing to analyze aerobic parameters before and after three to six months of supervised aerobic exercise training. Before training, younger subjects had a much higher exercise capacity, as shown by a 42% higher peak oxygen consumption (VO2) (ml/kg/min, p < 0.0001). This was associated with an 11% lower work VO2/W (p = 0.02) and an 8% higher efficiency than older subjects (p = 0.03). With training, older subjects displayed a larger increase in peak W/kg (+29% vs. +12%, p = 0.001), a larger decrease in work VO2/W (-24% vs. -2%, p < 0.0001), and a greater improvement in exercise efficiency (+30% vs. 2%, p < 0.0001) compared to the young. Older age is associated with a decreased exercise efficiency and an increase in the oxygen cost of exercise, which contribute to a decreased exercise capacity. These age-related changes are reversed with exercise training, which improves efficiency to a greater degree in the elderly than in the young.

Left ventricular dyssynchrony in patients with normal ventricular systolic function referred for exercise echocardiography.

PubMed

Bernheim, Alain M; Nakajima, Yoshie; Pellikka, Patricia A

2008-10-01

Exercise testing is often normal despite the presence of exertional symptoms. We hypothesized that left ventricular (LV) dyssynchrony might occur in some patients in the absence of ischemia, LV dysfunction, or wide QRS, and might contribute to exertional symptoms and diminished exercise capacity. Echocardiographic parameters were assessed before and with exercise in 40 patients (age 62 +/- 8 years, 27 with exertional symptoms). All had normal clinically indicated exercise echocardiograms and narrow QRS. The time to peak systolic velocity (Ts) was measured in 12 segments to calculate the standard deviation (Ts-SD) and the maximal difference (Ts-diff). At rest, 25 patients (63%) had dyssynchrony by Ts-SD. With exercise, mean Ts-SD did not increase significantly (34.9 +/- 19.3 ms vs 39.5 +/- 27.2 ms, P = .28). However, Ts-SD increased by greater than 40% in 15 patients (37.5%), remained stable in 19 patients (47.5%), and decreased by greater than 40% in 6 patients (15%). Similar responses were observed for Ts-diff. Patients with exercise-induced dyssynchrony were not more likely to have symptoms. Exercise capacity was inversely correlated with resting Ts-SD (r = -0.37, P = .02) and resting Ts-diff (r = -0.38, P = .02), but not with exercise-induced changes in dyssynchrony. Patients with resting dyssynchrony had higher resting heart rate (73 +/- 12 vs 63 +/- 11 beats/min, P = .02). LV dyssynchrony may occur more frequently than previously thought and may develop with exercise in the absence of ischemia. Exercise-induced LV dyssynchrony was not related to exertional symptoms or exercise capacity. Patients with dyssynchrony at rest had a higher resting heart rate and achieved a lower workload; this may indicate early myocardial impairment.

Effects of Obstructive Sleep Apnea and Obesity on Exercise Function in Children

PubMed Central

Evans, Carla A.; Selvadurai, Hiran; Baur, Louise A.; Waters, Karen A.

2014-01-01

Study Objectives: Evaluate the relative contributions of weight status and obstructive sleep apnea (OSA) to cardiopulmonary exercise responses in children. Design: Prospective, cross-sectional study. Participants underwent anthropometric measurements, overnight polysomnography, spirometry, cardiopulmonary exercise function testing on a cycle ergometer, and cardiac doppler imaging. OSA was defined as ≥ 1 obstructive apnea or hypopnea per hour of sleep (OAHI). The effect of OSA on exercise function was evaluated after the parameters were corrected for body mass index (BMI) z-scores. Similarly, the effect of obesity on exercise function was examined when the variables were adjusted for OAHI. Setting: Tertiary pediatric hospital. Participants: Healthy weight and obese children, aged 7–12 y. Interventions: N/A. Measurements and Results: Seventy-one children were studied. In comparison with weight-matched children without OSA, children with OSA had a lower cardiac output, stroke volume index, heart rate, and oxygen consumption (VO2 peak) at peak exercise capacity. After adjusting for BMI z-score, children with OSA had 1.5 L/min (95% confidence interval -2.3 to -0.6 L/min; P = 0.001) lower cardiac output at peak exercise capacity, but minute ventilation and ventilatory responses to exercise were not affected. Obesity was only associated with physical deconditioning. Cardiac dysfunction was associated with the frequency of respiratory-related arousals, the severity of hypoxia, and heart rate during sleep. Conclusions: Children with OSA are exercise limited due to a reduced cardiac output and VO2 peak at peak exercise capacity, independent of their weight status. Comorbid OSA can further decrease exercise performance in obese children. Citation: Evans CA, Selvadurai H, Baur LA, Waters KA. Effects of obstructive sleep apnea and obesity on exercise function in children. SLEEP 2014;37(6):1103-1110. PMID:24882905

Cardiovascular Effects of 1 Year of Alagebrium and Endurance Exercise Training in Healthy Older Individuals

PubMed Central

Fujimoto, Naoki; Hastings, Jeffrey L.; Carrick-Ranson, Graeme; Shafer, Keri M.; Shibata, Shigeki; Bhella, Paul S.; Abdullah, Shuaib M.; Barkley, Kyler W.; Adams-Huet, Beverley; Boyd, Kara N.; Livingston, Sheryl A.; Palmer, Dean; Levine, Benjamin D.

2014-01-01

Background Lifelong exercise training maintains a youthful compliance of the left ventricle (LV), whereas a year of exercise training started later in life fails to reverse LV stiffening, possibly because of accumulation of irreversible advanced glycation end products. Alagebrium breaks advanced glycation end product crosslinks and improves LV stiffness in aged animals. However, it is unclear whether a strategy of exercise combined with alagebrium would improve LV stiffness in sedentary older humans. Methods and Results Sixty-two healthy subjects were randomized into 4 groups: sedentary+placebo; sedentary+alagebrium (200 mg/d); exercise+placebo; and exercise+alagebrium. Subjects underwent right heart catheterization to define LV pressure–volume curves; secondary functional outcomes included cardiopulmonary exercise testing and arterial compliance. A total of 57 of 62 subjects (67±6 years; 37 f/20 m) completed 1 year of intervention followed by repeat measurements. Pulmonary capillary wedge pressure and LV end-diastolic volume were measured at baseline, during decreased and increased cardiac filling. LV stiffness was assessed by the slope of LV pressure–volume curve. After intervention, LV mass and end-diastolic volume increased and exercise capacity improved (by ≈8%) only in the exercise groups. Neither LV mass nor exercise capacity was affected by alagebrium. Exercise training had little impact on LV stiffness (training×time effect, P=0.46), whereas alagebrium showed a modest improvement in LV stiffness compared with placebo (medication×time effect, P=0.04). Conclusions Alagebrium had no effect on hemodynamics, LV geometry, or exercise capacity in healthy, previously sedentary seniors. However, it did show a modestly favorable effect on age-associated LV stiffening. PMID:24130005

Quality of life questionnaire predicts poor exercise capacity only in HFpEF and not in HFrEF.

PubMed

Ahmeti, Artan; Henein, Michael Y; Ibrahimi, Pranvera; Elezi, Shpend; Haliti, Edmond; Poniku, Afrim; Batalli, Arlind; Bajraktari, Gani

2017-10-17

The Minnesota Living with Heart Failure Questionnaire (MLHFQ) is the most widely used measure of quality of life (QoL) in HF patients. This prospective study aimed to assess the relationship between QoL and exercise capacity in HF patients. The study subjects were 118 consecutive patients with chronic HF (62 ± 10 years, 57 females, in NYHA I-III). Patients answered a MLHFQ questionnaire in the same day of complete clinical, biochemical and echocardiographic assessment. They also underwent a 5 min walk test (6-MWT), in the same day, which grouped them into; Group I: ≤ 300 m and Group II: >300 m. In addition, left ventricular (LV) ejection fraction (EF), divided them into: Group A, with preserved EF (HFpEF) and Group B with reduced EF (HFrEF). The mean MLHFQ total scale score was 48 (±17). The total scale, and the physical and emotional functional MLHFQ scores did not differ between HFpEF and HFpEF. Group I patients were older (p = 0.003), had higher NYHA functional class (p = 0.002), faster baseline heart rate (p = 0.006), higher prevalence of smoking (p = 0.015), higher global, physical and emotional MLHFQ scores (p < 0.001, for all), larger left atrial (LA) diameter (p = 0.001), shorter LV filling time (p = 0.027), higher E/e' ratio (0.02), shorter isovolumic relaxation time (p = 0.028), lower septal a' (p = 0.019) and s' (p = 0.023), compared to Group II. Independent predictors of 6-MWT distance for the group as a whole were increased MLHFQ total score (p = 0.005), older age (p = 0.035), and diabetes (p = 0.045), in HFpEF were total MLHFQ (p = 0.007) and diabetes (p = 0.045) but in HFrEF were only LA enlargement (p = 0.005) and age (p = 0.013. A total MLHFQ score of 48.5 had a sensitivity of 67% and specificity of 63% (AUC on ROC analysis of 72%) for limited exercise performance in HF patients. Quality of life, assessment by MLHFQ, is the best correlate of exercise capacity measured by 6-MWT, particularly in HFpEF patients. Despite worse ejection fraction in HFrEF, signs of raised LA pressure independently determine exercise capacity in these patients.

Peripheral Vascular Disease: The Beneficial Effect of Exercise in Peripheral Vascular Diseases Based on Clinical Trials.

PubMed

Elnady, Basant M; Saeed, Ayman

2017-01-01

Intermittent claudication (IC) due to peripheral artery diseases (PAD) is one of the disabling disease that can affect quality of life (QOL) and functional status of capacity. It is characterized by cramping pain which develops with exercise and eliminated by rest secondary to decrease blood flow to the muscles. The annual incidence rate is increased with age. Exercise rehabilitation has a great impact in improving the functional capacity and prevent the functional disability. The available evidences from current studies have showed that exercise therapy is considered the primary treatment in PAD, which in consequently improves the QOL. In this chapter we will illustrate the current available evidences which support exercise benefit and outcomes in PAD with IC.

Variable prognostic value of blood pressure response to exercise.

PubMed

Kato, Yuko; Suzuki, Shinya; Uejima, Tokuhisa; Semba, Hiroaki; Yamashita, Takeshi

2018-01-01

The aim of this study was to evaluate the impact of patient background including exercise capacity on the relationship between the blood pressure (BP) response to exercise and prognosis in patients visiting a cardiovascular hospital. A total of 2134 patients who were referred to our hospital underwent symptom-limited maximal cardiopulmonary exercise testing, and were followed through medical records and mail. The BP response to exercise was defined as the difference between peak and rest systolic BP. The end point was set as cardiovascular events including cardiovascular death, acute coronary syndrome, hospitalization for heart failure, and cerebral infarction. During a median follow-up period of 3 years, 179 (8%) patients reached the end point (2.5%/year). Multivariate analysis showed that BP response was independently and negatively associated with the occurrence of the end point. This prognostic significance of BP response was consistent regardless of left ventricular ejection fraction, renal function, presence of heart failure symptoms, the presence of organic heart disease, and hypertension. However, peak VO 2 showed a significant interaction with the effects of BP response on the end point, suggesting that the prognostic value of BP response was limited in patients with preserved exercise capacity. The role of BP response to exercise as the predictor depends on exercise capacity of each patient. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

The effect of habitual waterpipe tobacco smoking on pulmonary function and exercise capacity in young healthy males: A pilot study.

PubMed

Hawari, F I; Obeidat, N A; Ghonimat, I M; Ayub, H S; Dawahreh, S S

2017-01-01

Evidence regarding the health effects of habitual waterpipe smoking is limited, particularly in young smokers. Respiratory health and cardiopulmonary exercise tests were compared in young male habitual waterpipe smokers (WPS) versus non-smokers. 69 WPS (≥3 times/week for three years) and 69 non-smokers were studied. Respiratory health was assessed through the American Thoracic Society and the Division of Lung Diseases (ATS-DLD-78) adult questionnaire. Pulmonary function and cardiopulmonary exercise tests were performed. Self-reported respiratory symptoms, forced expiratory volume in first second (FEV 1 ), forced vital capacity (FVC), FEV 1 /FVC ratio, forced expiratory flow between 25 and 75% of FVC (FEF 25-75% ), peak expiratory flow (PEF), exercise time, peak end-tidal CO 2 tension (PetCO 2 ), subject-reported leg fatigue and dyspnea; peak O 2 uptake (VO 2 max), and end-expiratory lung volume (EELV) change from baseline (at peak exercise) were measured. WPS were more likely than non-smokers to report respiratory symptoms. WPS also demonstrated: shorter exercise time; lower peak VO 2 ; higher perceived dyspnea at mid-exercise; lower values of the following: FEV 1 , FVC, PEF, and EELV change. Habitual waterpipe tobacco smoking in young seemingly healthy individuals is associated with a greater burden of respiratory symptoms and impaired exercise capacity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recovery of pulmonary functions, exercise capacity, and quality of life after pulmonary rehabilitation in survivors of ARDS due to severe influenza A (H1N1) pneumonitis.

PubMed

Hsieh, Meng-Jer; Lee, Wei-Chun; Cho, Hsiu-Ying; Wu, Meng-Fang; Hu, Han-Chung; Kao, Kuo-Chin; Chen, Ning-Hung; Tsai, Ying-Huang; Huang, Chung-Chi

2018-04-20

Acute respiratory distress syndrome (ARDS) due to severe influenza A H1N1 pneumonitis would result in impaired pulmonary functions and health-related quality of life (HRQoL) after hospital discharge. The recovery of pulmonary functions, exercise capacity, and HRQoL in the survivors of ARDS due to 2009 pandemic influenza A H1N1 pneumonitis (H1N1-ARDS) was evaluated in a tertiary teaching hospital in northern Taiwan between May 2010 and June 2011. Data of spirometry, total lung capacity (TLC), diffusing capacity of carbon monoxide (DL CO ), and 6-minute walk distance (6MWD) in the patients survived from H1N1-ARDS were collected 1, 3, and 6 months post-hospital discharge. HRQoL was evaluated with St. George respiratory questionnaire (SGRQ). Nine survivors of H1N1-ARDS in the study period were included. All these patients received 2 months' pulmonary rehabilitation program. Pulmonary functions and exercise capacity included TLC, forced vital capacity (FVC), forced expiratory volume in the first second (FEV 1 ), DL CO , and 6MWD improved from 1 to 3 months post-hospital discharge. Only TLC had further significant improvement from 3 to 6 months. HRQoL represented as the total score of SGRQ had no significant improvement in the first 3 months but improved significantly from 3 to 6 months post-discharge. The impaired pulmonary functions and exercise capacity in the survivors of H1N1-ARDS improved soon at 3 months after hospital discharge. Their quality of life had keeping improved at 6 months even though there was no further improvement of their pulmonary functions and exercise capacity. © 2018 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Sweat Rates During Continuous and Interval Aerobic Exercise: Implications for NASA Multipurpose Crew Vehicle (MPCV) Missions

NASA Technical Reports Server (NTRS)

Ryder, Jeffrey W.; Scott, Jessica; Ploutz-Snyder, Robert; Ploutz-Snyder, Lori L.

2016-01-01

Aerobic deconditioning is one of the effects spaceflight. Impaired crewmember performance due to loss of aerobic conditioning is one of the risks identified for mitigation by the NASA Human Research Program. Missions longer than 8 days will involve exercise countermeasures including those aimed at preventing the loss of aerobic capacity. The NASA Multipurpose Crew Vehicle (MPCV) will be NASA's centerpiece architecture for human space exploration beyond low Earth orbit. Aerobic exercise within the small habitable volume of the MPCV is expected to challenge the ability of the environmental control systems, especially in terms of moisture control. Exercising humans contribute moisture to the environment by increased respiratory rate (exhaling air at 100% humidity) and sweat. Current acceptable values are based on theoretical models that rely on an "average" crew member working continuously at 75% of their aerobic capacity (Human Systems Integration Requirements Document). Evidence suggests that high intensity interval exercise for much shorter durations are equally effective or better in building and maintaining aerobic capacity. This investigation will examine sweat and respiratory rates for operationally relevant continuous and interval aerobic exercise protocols using a variety of different individuals. The results will directly inform what types of aerobic exercise countermeasures will be feasible to prescribe for crewmembers aboard the MPCV.

Astrocytic glycogen-derived lactate fuels the brain during exhaustive exercise to maintain endurance capacity

PubMed Central

Matsui, Takashi; Omuro, Hideki; Liu, Yu-Fan; Soya, Mariko; Shima, Takeru; McEwen, Bruce S.; Soya, Hideaki

2017-01-01

Brain glycogen stored in astrocytes provides lactate as an energy source to neurons through monocarboxylate transporters (MCTs) to maintain neuronal functions such as hippocampus-regulated memory formation. Although prolonged exhaustive exercise decreases brain glycogen, the role of this decrease and lactate transport in the exercising brain remains less clear. Because muscle glycogen fuels exercising muscles, we hypothesized that astrocytic glycogen plays an energetic role in the prolonged-exercising brain to maintain endurance capacity through lactate transport. To test this hypothesis, we used a rat model of exhaustive exercise and capillary electrophoresis-mass spectrometry–based metabolomics to observe comprehensive energetics of the brain (cortex and hippocampus) and muscle (plantaris). At exhaustion, muscle glycogen was depleted but brain glycogen was only decreased. The levels of MCT2, which takes up lactate in neurons, increased in the brain, as did muscle MCTs. Metabolomics revealed that brain, but not muscle, ATP was maintained with lactate and other glycogenolytic/glycolytic sources. Intracerebroventricular injection of the glycogen phosphorylase inhibitor 1,4-dideoxy-1,4-imino-d-arabinitol did not affect peripheral glycemic conditions but suppressed brain lactate production and decreased hippocampal ATP levels at exhaustion. An MCT2 inhibitor, α-cyano-4-hydroxy-cinnamate, triggered a similar response that resulted in lower endurance capacity. These findings provide direct evidence for the energetic role of astrocytic glycogen-derived lactate in the exhaustive-exercising brain, implicating the significance of brain glycogen level in endurance capacity. Glycogen-maintained ATP in the brain is a possible defense mechanism for neurons in the exhausted brain. PMID:28515312

Astrocytic glycogen-derived lactate fuels the brain during exhaustive exercise to maintain endurance capacity.

PubMed

Matsui, Takashi; Omuro, Hideki; Liu, Yu-Fan; Soya, Mariko; Shima, Takeru; McEwen, Bruce S; Soya, Hideaki

2017-06-13

Brain glycogen stored in astrocytes provides lactate as an energy source to neurons through monocarboxylate transporters (MCTs) to maintain neuronal functions such as hippocampus-regulated memory formation. Although prolonged exhaustive exercise decreases brain glycogen, the role of this decrease and lactate transport in the exercising brain remains less clear. Because muscle glycogen fuels exercising muscles, we hypothesized that astrocytic glycogen plays an energetic role in the prolonged-exercising brain to maintain endurance capacity through lactate transport. To test this hypothesis, we used a rat model of exhaustive exercise and capillary electrophoresis-mass spectrometry-based metabolomics to observe comprehensive energetics of the brain (cortex and hippocampus) and muscle (plantaris). At exhaustion, muscle glycogen was depleted but brain glycogen was only decreased. The levels of MCT2, which takes up lactate in neurons, increased in the brain, as did muscle MCTs. Metabolomics revealed that brain, but not muscle, ATP was maintained with lactate and other glycogenolytic/glycolytic sources. Intracerebroventricular injection of the glycogen phosphorylase inhibitor 1,4-dideoxy-1,4-imino-d-arabinitol did not affect peripheral glycemic conditions but suppressed brain lactate production and decreased hippocampal ATP levels at exhaustion. An MCT2 inhibitor, α-cyano-4-hydroxy-cinnamate, triggered a similar response that resulted in lower endurance capacity. These findings provide direct evidence for the energetic role of astrocytic glycogen-derived lactate in the exhaustive-exercising brain, implicating the significance of brain glycogen level in endurance capacity. Glycogen-maintained ATP in the brain is a possible defense mechanism for neurons in the exhausted brain.

Physiological Correlates of Endurance Time Variability during Constant-Workrate Cycling Exercise in Patients with COPD

PubMed Central

Vivodtzev, Isabelle; Gagnon, Philippe; Pepin, Véronique; Saey, Didier; Laviolette, Louis; Brouillard, Cynthia; Maltais, François

2011-01-01

Rationale The endurance time (Tend) during constant-workrate cycling exercise (CET) is highly variable in COPD. We investigated pulmonary and physiological variables that may contribute to these variations in Tend. Methods Ninety-two patients with COPD completed a CET performed at 80% of peak workrate capacity (Wpeak). Patients were divided into tertiles of Tend [Group 1: <4 min; Group 2: 4–6 min; Group 3: >6 min]. Disease severity (FEV1), aerobic fitness (Wpeak, peak oxygen consumption [ peak], ventilatory threshold [ VT]), quadriceps strength (MVC), symptom scores at the end of CET and exercise intensity during CET (heart rate at the end of CET to heart rate at peak incremental exercise ratio [HRCET/HRpeak]) were analyzed as potential variables influencing Tend. Results Wpeak, peak, VT, MVC, leg fatigue at end of CET, and HRCET/HRpeak were lower in group 1 than in group 2 or 3 (p≤0.05). VT and leg fatigue at end of CET independently predicted Tend in multiple regression analysis (r = 0.50, p = 0.001). Conclusion Tend was independently related to the aerobic fitness and to tolerance to leg fatigue at the end of exercise. A large fraction of the variability in Tend was not explained by the physiological parameters assessed in the present study. Individualization of exercise intensity during CET should help in reducing variations in Tend among patients with COPD. PMID:21386991

“Nutraceuticals” in relation to human skeletal muscle and exercise

PubMed Central

Deane, Colleen S.; Wilkinson, Daniel J.; Phillips, Bethan E.; Smith, Kenneth; Etheridge, Timothy

2017-01-01

Skeletal muscles have a fundamental role in locomotion and whole body metabolism, with muscle mass and quality being linked to improved health and even lifespan. Optimizing nutrition in combination with exercise is considered an established, effective ergogenic practice for athletic performance. Importantly, exercise and nutritional approaches also remain arguably the most effective countermeasure for muscle dysfunction associated with aging and numerous clinical conditions, e.g., cancer cachexia, COPD, and organ failure, via engendering favorable adaptations such as increased muscle mass and oxidative capacity. Therefore, it is important to consider the effects of established and novel effectors of muscle mass, function, and metabolism in relation to nutrition and exercise. To address this gap, in this review, we detail existing evidence surrounding the efficacy of a nonexhaustive list of macronutrient, micronutrient, and “nutraceutical” compounds alone and in combination with exercise in relation to skeletal muscle mass, metabolism (protein and fuel), and exercise performance (i.e., strength and endurance capacity). It has long been established that macronutrients have specific roles and impact upon protein metabolism and exercise performance, (i.e., protein positively influences muscle mass and protein metabolism), whereas carbohydrate and fat intakes can influence fuel metabolism and exercise performance. Regarding novel nutraceuticals, we show that the following ones in particular may have effects in relation to 1) muscle mass/protein metabolism: leucine, hydroxyl β-methylbutyrate, creatine, vitamin-D, ursolic acid, and phosphatidic acid; and 2) exercise performance: (i.e., strength or endurance capacity): hydroxyl β-methylbutyrate, carnitine, creatine, nitrates, and β-alanine. PMID:28143855

38 CFR 4.96 - Special provisions regarding evaluation of respiratory conditions.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-6845. (1) Pulmonary function tests (PFT's) are required to evaluate these conditions except: (i) When the results of a maximum exercise capacity test are of record and are 20 ml/kg/min or less. If a maximum exercise capacity test is not of record, evaluate based on alternative criteria. (ii) When...

[Ergometric results of r-erythropoietin treatment of hemodialysis patients].

PubMed

Hortian, B; Schmidt, R; Wüstenberg, P W; Dörp, E; Schumann, L; Winkler, R; Klinkmann, H

1990-05-15

To investigate the effect of partial correction of anemia in patients maintained by chronic intermittent hemodialysis on exercise capacity, patients underwent a bicycle acido-ergometry before and after treatment with recombinant human erythropoietin. The results demonstrate a (subjective) improvement of exercise capacity without any evidence for that in the pH values.

Exercise Training for Heart Failure Patients with and without Systolic Dysfunction: An Evidence-Based Analysis of How Patients Benefit

PubMed Central

Smart, Neil

2011-01-01

Significant benefits can be derived by heart failure patients from exercise training. This paper provides an evidence-based assessment of expected clinical benefits of exercise training for heart failure patients. Meta-analyses and randomized, controlled trials of exercise training in heart failure patients were reviewed from a search of PubMed, Cochrane Controlled Trial Registry (CCTR), CINAHL, and EMBASE. Exercise training improves functional capacity, quality of life, hospitalization, and systolic and diastolic function in heart failure patients. Heart failure patients with preserved systolic function (HFnEF) participating in exercise training studies are more likely to be women and are 5–7 years older than their systolic heart failure (CHF) counterparts. All patients exhibit low functional capacities, although in HFnEF patients this may be age related, therefore subtle differences in exercise prescriptions are required. Published works report that exercise training is beneficial for heart failure patients with and without systolic dysfunction. PMID:20953365

Benefits of physical exercise training on cognition and quality of life in frail older adults.

PubMed

Langlois, Francis; Vu, Thien Tuong Minh; Chassé, Kathleen; Dupuis, Gilles; Kergoat, Marie-Jeanne; Bherer, Louis

2013-05-01

Frailty is a state of vulnerability associated with increased risks of fall, hospitalization, cognitive deficits, and psychological distress. Studies with healthy senior suggest that physical exercise can help improve cognition and quality of life. Whether frail older adults can show such benefits remains to be documented. A total of 83 participants aged 61-89 years were assigned to an exercise-training group (3 times a week for 12 weeks) or a control group (waiting list). Frailty was determined by a complete geriatric examination using specific criteria. Pre- and post-test measures assessed physical capacity, cognitive performance, and quality of life. Compared with controls, the intervention group showed significant improvement in physical capacity (functional capacities and physical endurance), cognitive performance (executive functions, processing speed, and working memory), and quality of life (global quality of life, leisure activities, physical capacity, social/family relationships, and physical health). Benefits were overall equivalent between frail and nonfrail participants. Physical exercise training leads to improved cognitive functioning and psychological well-being in frail older adults.

[Effects of an inpatient pulmonary rehabilitation program on dyspnea, exercise capacity, and health related quality of life for patients with chronic lung disease].

PubMed

Lee, Chang Kwan

2007-04-01

The purpose of this study was to examine the effects of an inpatient pulmonary rehabilitation program on dyspnea, exercise capacity, and health related quality of life in inpatients with chronic lung disease. This quasi experimental study was designed with a nonequivalent control group pre-post test time series. Twenty three patients were assigned to the experimental group and nineteen to the control group. The inpatient pulmonary rehabilitation program was composed of upper and lower extremity exercise, breathing retraining, inspiratory muscle training, education, relaxation and telephone contacts. This program consisted of 4 sessions with inpatients and 4 weeks at home after discharge. The control group was given a home based pulmonary rehabilitation program at the time of discharge. The outcomes were measured by the Borg score, 6MWD and the Chronic Respiratory Disease Questionnaire(CRQ). There was a statistically significant difference in dyspnea between the experimental group and control group, but not among time sequence, or interaction between groups and time sequence. Also significant improvements in exercise capacity and health related quality of life were found only in the experimental group. An Inpatient pulmonary rehabilitation program may be a useful intervention to reduce dyspnea, and increase exercise capacity and health related quality of life for chronic lung disease patients.

Physical function was related to mortality in patients with chronic kidney disease and dialysis.

PubMed

Morishita, Shinichiro; Tsubaki, Atsuhiro; Shirai, Nobuyuki

2017-10-01

Previous studies have shown that exercise improves aerobic capacity, muscular functioning, cardiovascular function, walking capacity, and health-related quality of life (QOL) in patients with chronic kidney disease (CKD) and dialysis. Recently, additional studies have shown that higher physical activity contributes to survival and decreased mortality as well as physical function and QOL in patients with CKD and dialysis. Herein, we review the evidence that physical function and physical activity play an important role in mortality for patients with CKD and dialysis. During November 2016, Medline and Web of Science databases were searched for published English medical reports (without a time limit) using the terms "CKD" or "dialysis" and "mortality" in conjunction with "exercise capacity," "muscle strength," "activities of daily living (ADL)," "physical activity," and "exercise." Numerous studies suggest that higher exercise capacity, muscle strength, ADL, and physical activity contribute to lower mortality in patients with CKD and dialysis. Physical function is associated with mortality in patients with CKD and dialysis. Increasing physical function may decrease the mortality rate of patients with CKD and dialysis. Physicians and medical staff should recognize the importance of physical function in CKD and dialysis. In addition, exercise is associated with reduced mortality among patients with CKD and dialysis. © 2017 International Society for Hemodialysis.

Effect of prolonged exercise on oxidative damage and susceptibility to oxidants of rat tissues in severe hyperthyroidism.

PubMed

Venditti, P; De Rosa, R; Caldarone, G; Di Meo, S

2005-10-15

We investigated effects of prolonged aerobic exercise and severe hyperthyroidism on indices of oxidative damage, susceptibility to oxidants, and respiratory capacity of homogenates from rat liver, heart and skeletal muscle. Both treatments induced increases in hydroperoxide and protein-bound carbonyl levels. Moreover, the highest increases were found when hyperthyroid animals were subjected to exercise. These changes, which were associated to reduced exercise endurance capacity, were in part due to higher susceptibility to oxidants of hyperthyroid tissues. Levels of oxidative damage indices were scarcely related to changes in antioxidant enzyme activities and lipid-soluble antioxidant concentrations. However, the finding that, following exercise the scavenger levels generally decreased in liver homogenates and increased in heart and muscles ones, suggested a net shuttle of antioxidants from liver to other tissues under need. Aerobic capacity, evaluated by cytochrome oxidase activity, was not modified by exercise, which, conversely, affected the rates of oxygen consumption of hyperthyroid preparations. These results seem to confirm the higher susceptibility of hyperthyroid tissues to oxidative challenge, because the mechanisms underlying the opposite changes in respiration rates during State 4 and State 3 likely involve oxidative modifications of components of mitochondrial respiratory chain, different from cytochrome aa3.

Relationship between nutritional risk and exercise capacity in severe chronic obstructive pulmonary disease in male patients

PubMed Central

Shan, Xizheng; Liu, Jinming; Luo, Yanrong; Xu, Xiaowen; Han, Zhiqing; Li, Hailing

2015-01-01

Objective The nutritional status of chronic obstructive pulmonary disease (COPD) patients is associated with their exercise capacity. In the present study, we have explored the relationship between nutritional risk and exercise capacity in severe male COPD patients. Methods A total of 58 severe COPD male patients were enrolled in this study. The patients were assigned to no nutritional risk group (n=33) and nutritional risk group (n=25) according to the Nutritional Risk Screening (NRS, 2002) criteria. Blood gas analysis, conventional pulmonary function testing, and cardiopulmonary exercise testing were performed on all the patients. Results Results showed that the weight and BMI of the patients in the nutritional risk group were significantly lower than in the no nutritional risk group (P<0.05). The pulmonary diffusing capacity for carbon monoxide of the no nutritional risk group was significantly higher than that of the nutritional risk group (P<0.05). Besides, the peak VO2 (peak oxygen uptake), peak O2 pulse (peak oxygen pulse), and peak load of the nutritional risk group were significantly lower than those of the no nutritional risk group (P<0.05) and there were significantly negative correlations between the NRS score and peak VO2, peak O2 pulse, or peak load (r<0, P<0.05). Conclusion The association between exercise capacity and nutritional risk based on NRS 2002 in severe COPD male patients is supported by these results of this study. PMID:26150712

Wii-Workouts on Chronic Pain, Physical Capabilities and Mood of Older Women: A Randomized Controlled Double Blind Trial.

PubMed

Monteiro-Junior, Renato Sobral; de Souza, Cíntia Pereira; Lattari, Eduardo; Rocha, Nuno Barbosa Ferreira; Mura, Gioia; Machado, Sérgio; da Silva, Elirez Bezerra

2015-01-01

Chronic Low Back Pain (CLBP) is a public health problem and older women have higher incidence of this symptom, which affect body balance, functional capacity and behavior. The purpose of this study was to verifying the effect of exercises with Nintendo Wii on CLBP, functional capacity and mood of elderly. Thirty older women (68 ± 4 years; 68 ± 12 kg; 154 ± 5 cm) with CLBP participated in this study. Elderly individuals were divided into a Control Exercise Group (n = 14) and an Experimental Wii Group (n = 16). Control Exercise Group did strength exercises and core training, while Experimental Wii Group did ones additionally to exercises with Wii. CLBP, balance, functional capacity and mood were assessed pre and post training by the numeric pain scale, Wii Balance Board, sit to stand test and Profile of Mood States, respectively. Training lasted eight weeks and sessions were performed three times weekly. MANOVA 2 x 2 showed no interaction on pain, siting, stand-up and mood (P = 0.53). However, there was significant difference within groups (P = 0.0001). ANOVA 2 x 2 showed no interaction for each variable (P > 0.05). However, there were significant differences within groups in these variables (P < 0.05). Tukey's post-hoc test showed significant difference in pain on both groups (P = 0.0001). Wilcoxon and Mann-Whitney tests identified no significant differences on balance (P > 0.01). Capacity to Sit improved only in Experimental Wii Group (P = 0.04). In conclusion, physical exercises with Nintendo Wii Fit Plus additional to strength and core training were effective only for sitting capacity, but effect size was small.

Pulmonary circulation and gas exchange at exercise in Sherpas at high altitude.

PubMed

Faoro, Vitalie; Huez, Sandrine; Vanderpool, Rebecca; Groepenhoff, Herman; de Bisschop, Claire; Martinot, Jean-Benot; Lamotte, Michel; Pavelescu, Adriana; Guénard, Hervé; Naeije, Robert

2014-04-01

Tibetans have been reported to present with a unique phenotypic adaptation to high altitude characterized by higher resting ventilation and arterial oxygen saturation, no excessive polycythemia, and lower pulmonary arterial pressures (Ppa) compared with other high-altitude populations. How this affects exercise capacity is not exactly known. We measured aerobic exercise capacity during an incremental cardiopulmonary exercise test, lung diffusing capacity for carbon monoxide (DL(CO)) and nitric oxide (DL(NO)) at rest, and mean Ppa (mPpa) and cardiac output by echocardiography at rest and at exercise in 13 Sherpas and in 13 acclimatized lowlander controls at the altitude of 5,050 m in Nepal. In Sherpas vs. lowlanders, arterial oxygen saturation was 86 ± 1 vs. 83 ± 2% (mean ± SE; P = nonsignificant), mPpa at rest 19 ± 1 vs. 23 ± 1 mmHg (P < 0.05), DL(CO) corrected for hemoglobin 61 ± 4 vs. 37 ± 2 ml · min(-1) · mmHg(-1) (P < 0.001), DL(NO) 226 ± 18 vs. 153 ± 9 ml · min(-1) · mmHg(-1) (P < 0.001), maximum oxygen uptake 32 ± 3 vs. 28 ± 1 ml · kg(-1) · min(-1) (P = nonsignificant), and ventilatory equivalent for carbon dioxide at anaerobic threshold 40 ± 2 vs. 48 ± 2 (P < 0.001). Maximum oxygen uptake was correlated directly to DL(CO) and inversely to the slope of mPpa-cardiac index relationships in both Sherpas and acclimatized lowlanders. We conclude that Sherpas compared with acclimatized lowlanders have an unremarkable aerobic exercise capacity, but with less pronounced pulmonary hypertension, lower ventilatory responses, and higher lung diffusing capacity.

Exercise capacity and progression from prehypertension to hypertension.

PubMed

Faselis, Charles; Doumas, Michael; Kokkinos, John Peter; Panagiotakos, Demosthenes; Kheirbek, Raya; Sheriff, Helen M; Hare, Katherine; Papademetriou, Vasilios; Fletcher, Ross; Kokkinos, Peter

2012-08-01

Prehypertension is likely to progress to hypertension. The rate of progression is determined mostly by age and resting blood pressure but may also be attenuated by increased fitness. A graded exercise test was performed in 2303 men with prehypertension at the Veterans Affairs Medical Centers in Washington, DC. Four fitness categories were defined, based on peak metabolic equivalents (METs) achieved. We assessed the association between exercise capacity and rate of progression to hypertension (HTN). The median follow-up period was 7.8 years (mean (± SD) 9.2±6.1 years). The incidence rate of progression from prehypertension to hypertension was 34.4 per 1000 person-years. Exercise capacity was a strong and independent predictor of the rate of progression. Compared to the High-Fit individuals (>10.0 METs), the adjusted risk for developing HTN was 66% higher (hazard ratio, 1.66; 95% CI, 1.2 to 2.2; P=0.001) for the Low-Fit and, similarly, 72% higher (hazard ratio, 1.72; 95% CI, 1.2 to 2.3; P=0.001) for the Least-Fit individuals, whereas it was only 36% for the Moderate-Fit (hazard ratio, 1.36; 95% CI, 0.99 to 1.80; P=0.056). Significant predictors for the progression to HTN were also age (19% per 10 years), resting systolic blood pressure (16% per 10 mm Hg), body mass index (15.3% per 5 U), and type 2 diabetes mellitus (2-fold). In conclusion, an inverse, S-shaped association was shown between exercise capacity and the rate of progression from prehypertension to hypertension in middle-aged and older male veterans. The protective effects of fitness were evident when exercise capacity exceeded 8.5 METs. These findings emphasize the importance of fitness in the prevention of hypertension.

Influence of Disease Severity and Exercise Limitation on Exercise Training Intensity and Load and Health Benefits From Pulmonary Rehabilitation in Patients with COPD: AN EXPLORATORY STUDY.

PubMed

Huynh, Virginia C; Fuhr, Desi P; Byers, Bradley W; Selzler, Anne-Marie; Moore, Linn E; Stickland, Michael K

2018-04-11

Some patients with chronic obstructive pulmonary disease (COPD) fail to achieve health benefits with pulmonary rehabilitation (PR). Exercise intensity and load represent stimulus for adaptation but it is unclear whether inappropriate exercise intensity and/or load are affected by severity of COPD, which may affect health benefits. The purpose was to determine whether COPD severity and/or the severity of pulmonary limitation to exercise (PLE) impacted exercising intensity or load and whether resultant intensity/load affected health outcomes derived from PR. Patients with COPD (n = 58, age = 67 ± 7 y, forced expiratory volume in the first second of expiration [FEV1] % predicted = 52 ± 21%) were recruited upon referral to PR. Primary health outcomes evaluated were 6-min walk distance and St George's Respiratory Questionnaire. Patients were stratified for disease severity using Global Initiative for Obstructive Lung Disease (GOLD) staging and PLE severity by change in inspiratory capacity during exercise. Exercise intensity and load were calculated from daily exercise records. Participants achieved comparable training duration and load regardless of GOLD severity. Patients with more severe PLE achieved greater training duration (more severe: 546 ± 143 min., less severe: 451 ± 109 min., P = .036), and relative training load (more severe: 2200.8 ± 595.3 kcal, less severe: 1648.3 ± 597.8 kcal, P = .007). Greater overall training load was associated with greater improvements in 6-min walk distance (r = 0.24, P = .035). No significant relationships were observed between PLE, GOLD severity, training parameters, and St George's Respiratory Questionnaire response. Improvements in exercise tolerance can be explained by achieving greater training loads, demonstrating the importance of appropriate training load to maximize health outcomes in PR.

The influence of α-adducin gene polymorphism on response of blood pressure to exercise in patients with hypertension.

PubMed

Alioğlu, Emin; Ercan, Ertuğrul; Tengiz, Istemihan; Türk, Uğur Onsel; Ergün, Metin; Akgöz, Semra; Işlegen, Cetin; Berdeli, Afig

2010-10-01

Clinical studies have indicated that an excessive response of blood pressure (BP) to exercise predicts risk of cardiovascular mortality. Although the mechanism responsible for the excessive BP response to exercise has not been revealed, there are some plausible mechanisms linking with underlying structural abnormalities in the cardiovascular system. Carriers of the Trp460 allele of the α-adducin Gly460Trp polymorphism have an increased risk of hypertension. The aim of the present study was to examine the influence of α-adducin gene polymorphism on response of BP to exercise in patients with hypertension. The cross-sectional observational study consisted of 49 hypertensive patients (29 women and 20 men; mean age, 53.1±8.8 years). All participants underwent a multistage exercise treadmill test according to the Bruce protocol. Arterial BPs were compared at rest, peak exercise and end of the recovery phase. Patients were classified according to their α-adducin gene polymorphisms; Gly460Gly homozygotes - Group 1 (n=28) and Trp460Trp homozygotes and Gly460Trp heterozygotes - Group 2 (n=21). Statistical analysis was performed using Chi-square, unpaired t, Mann-Whitney U and ANCOVA tests. Mean exercise duration and mean exercise capacity in metabolic equivalents were not different between Group 1 and 2. The major finding of the study was that systolic BP responses at peak exercise and recovery period (3. min) were significantly higher (p=0.036) in hypertensive patients carrying at least one Trp460 allele of the α-adducin gene. Our results suggest that genetic variants that alter renal function and/or vasoreactivity are logical candidates to explain some of the individual variability in the BP response to exercise.

Prediction of adaptive self-regulatory responses to arthritis pain anxiety in exercising adults: does pain acceptance matter?

PubMed

Cary, Miranda Ashley; Gyurcsik, Nancy C; Brawley, Lawrence R

2015-01-01

Exercising for ≥ 150 min/week is a recommended strategy for self-managing arthritis. However, exercise nonadherence is a problem. Arthritis pain anxiety may interfere with regular exercise. According to the fear-avoidance model, individuals may confront their pain anxiety by using adaptive self-regulatory responses (eg, changing exercise type or duration). Furthermore, the anxiety-self-regulatory responses relationship may vary as a function of individuals' pain acceptance levels. To investigate pain acceptance as a moderator of the pain anxiety-adaptive self-regulatory responses relationship. The secondary objective was to examine whether groups of patients who differed in meeting exercise recommendations also differed in pain-related and self-regulatory responses. Adults (mean [± SD] age 49.75 ± 13.88 years) with medically diagnosed arthritis completed online measures of arthritis pain-related variables and self-regulatory responses at baseline, and exercise participation two weeks later. Individuals meeting (n=87) and not meeting (n=49) exercise recommendations were identified. Hierarchical multiple regression analysis revealed that pain acceptance moderated the anxiety-adaptive self-regulatory responses relationship. When pain anxiety was lower, greater pain acceptance was associated with less frequent use of adaptive responses. When anxiety was higher, adaptive responses were used regardless of pain acceptance level. MANOVA findings revealed that participants meeting the recommended exercise dose reported significantly lower pain and pain anxiety, and greater pain acceptance (P<0.05) than those not meeting the dose. Greater pain acceptance may help individuals to focus their efforts to adapt to their pain anxiety only when it is higher, leaving self-regulatory capacity to cope with additional challenges to exercise adherence (eg, busy schedule).

Prediction of adaptive self-regulatory responses to arthritis pain anxiety in exercising adults: Does pain acceptance matter?

PubMed Central

Cary, Miranda A; Gyurcsik, Nancy C; Brawley, Lawrence R

2015-01-01

BACKGROUND: Exercising for ≥150 min/week is a recommended strategy for self-managing arthritis. However, exercise nonadherence is a problem. Arthritis pain anxiety may interfere with regular exercise. According to the fear-avoidance model, individuals may confront their pain anxiety by using adaptive self-regulatory responses (eg, changing exercise type or duration). Furthermore, the anxiety-self-regulatory responses relationship may vary as a function of individuals’ pain acceptance levels. OBJECTIVES: To investigate pain acceptance as a moderator of the pain anxiety-adaptive self-regulatory responses relationship. The secondary objective was to examine whether groups of patients who differed in meeting exercise recommendations also differed in pain-related and self-regulatory responses. METHODS: Adults (mean [± SD] age 49.75±13.88 years) with medically diagnosed arthritis completed online measures of arthritis pain-related variables and self-regulatory responses at baseline, and exercise participation two weeks later. Individuals meeting (n=87) and not meeting (n=49) exercise recommendations were identified. RESULTS: Hierarchical multiple regression analysis revealed that pain acceptance moderated the anxiety-adaptive self-regulatory responses relationship. When pain anxiety was lower, greater pain acceptance was associated with less frequent use of adaptive responses. When anxiety was higher, adaptive responses were used regardless of pain acceptance level. MANOVA findings revealed that participants meeting the recommended exercise dose reported significantly lower pain and pain anxiety, and greater pain acceptance (P<0.05) than those not meeting the dose. CONCLUSIONS: Greater pain acceptance may help individuals to focus their efforts to adapt to their pain anxiety only when it is higher, leaving self-regulatory capacity to cope with additional challenges to exercise adherence (eg, busy schedule). PMID:25621990

Exercise capacity and all-cause mortality in male veterans with hypertension aged ≥70 years.

PubMed

Faselis, Charles; Doumas, Michael; Pittaras, Andreas; Narayan, Puneet; Myers, Jonathan; Tsimploulis, Apostolos; Kokkinos, Peter

2014-07-01

Aging, even in otherwise healthy subjects, is associated with declines in muscle mass, strength, and aerobic capacity. Older individuals respond favorably to exercise, suggesting that physical inactivity plays an important role in age-related functional decline. Conversely, physical activity and improved exercise capacity are associated with lower mortality risk in hypertensive individuals. However, the effect of exercise capacity in older hypertensive individuals has not been investigated extensively. A total of 2153 men with hypertension, aged ≥70 years (mean, 75 ± 4) from the Washington, DC, and Palo Alto Veterans Affairs Medical Centers, underwent routine exercise tolerance testing. Peak workload was estimated in metabolic equivalents (METs). Fitness categories were established based on peak METs achieved, adjusted for age: very-low-fit, 2.0 to 4.0 METs (n=386); low-fit, 4.1 to 6.0 METs (n=1058); moderate-fit, 6.1 to 8.0 METs (n=495); high-fit >8.0 METs (n=214). Cox proportional hazard models were applied after adjusting for age, body mass index, race, cardiovascular disease, cardiovascular medications, and risk factors. All-cause mortality was quantified during a mean follow-up period of 9.0 ± 5.5 years. There were a total of 1039 deaths or 51.2 deaths per 1000 person-years of follow-up. Mortality risk was 11% lower (hazard ratio, 0.89; 95% confidence interval, 0.86-0.93; P<0.001) for every 1-MET increase in exercise capacity. When compared with those achieving ≤4.0 METs, mortality risk was 18% lower (hazard ratio, 0.82; 95% confidence interval, 0.70-0.95; P=0.011) for the low-fit, 36% for the moderate-fit (hazard ratio, 0.64; 95% confidence interval, 0.52-0.78; P<0.001), and 48% for the high-fit individuals (hazard ratio, 0.52; 95% confidence interval, 0.39-0.69; P<0.001). These findings suggest that exercise capacity is associated with lower mortality risk in elderly men with hypertension. © 2014 American Heart Association, Inc.

The impact of iron deficiency and anaemia on exercise capacity and outcomes in patients with chronic heart failure. Results from the Studies Investigating Co-morbidities Aggravating Heart Failure.

PubMed

Ebner, Nicole; Jankowska, Ewa A; Ponikowski, Piotr; Lainscak, Mitja; Elsner, Sebastian; Sliziuk, Veronika; Steinbeck, Lisa; Kube, Jennifer; Bekfani, Tarek; Scherbakov, Nadja; Valentova, Miroslava; Sandek, Anja; Doehner, Wolfram; Springer, Jochen; Anker, Stefan D; von Haehling, Stephan

2016-02-15

Anaemia and iron deficiency (ID) are important co-morbidities in patients with chronic heart failure (HF) and both may lead to reduced exercise capacity. We enrolled 331 out-patients with stable chronic HF (mean age: 64 ± 11 years, 17% female, left ventricular ejection fraction [LVEF] 35 ± 13%, body mass index [BMI] 28.5 ± 5.2 kg/m(2), New York Heart Association [NYHA] class 2.2 ± 0.7, chronic kidney disease 35%, glomerular filtration rate 61.7 ± 20.1 mL/min). Anaemia was defined according to World Health Organization criteria (haemoglobin [Hb] < 13 g/dL in men, < 12 g/dL in women). ID was defined as serum ferritin < 100 μg/L or ferritin < 300 μg/L with transferrin saturation (TSAT) < 20%. Exercise capacity was assessed as peak oxygen consumption (peak VO2) by spiroergometry and 6-minute walk test (6MWT). A total of 91 (27%) patients died from any cause during a mean follow-up of 18 months. At baseline, 98 (30%) patients presented with anaemia and 149 (45%) patients presented with ID. We observed a significant reduction in exercise capacity in parallel to decreasing Hb levels (r = 0.24, p < 0.001). In patients with anaemia and ID (n = 63, 19%), exercise capacity was significantly lower than in patients with ID or anaemia only. Cox regression analysis showed that after adjusting for NYHA, age, hsCRP and creatinine anaemia is an independent predictor of mortality in patients with HF (hazard ratio [HR]: 0.56, 95% confidence interval [CI]: 0.33-0.97, p = 0.04). The impact of anaemia on reduced exercise capacity and on mortality is stronger than that of ID. Anaemia remained an independent predictor of death after adjusting for clinically relevant variables. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Integrative Conductance of Oxygen During Exercise at Altitude.

PubMed

Calbet, José A L; Lundby, Carsten; Boushel, Robert

2016-01-01

In the oxygen (O2) cascade downstream steps can never achieve higher flows of O2 than the preceding ones. At the lung the transfer of O2 is determined by the O2 gradient between the alveolar space and the lung capillaries and the O2 diffusing capacity (DLO2). While DLO2 may be increased several times during exercise by recruiting more lung capillaries and by increasing the oxygen carrying capacity of blood due to higher peripheral extraction of O2, the capacity to enhance the alveolocapillary PO2 gradient is more limited. The transfer of oxygen from the alveolar space to the hemoglobin (Hb) must overcome first the resistance offered by the alveolocapillary membrane (1/DM) and the capillary blood (1/θVc). The fractional contribution of each of these two components to DLO2 remains unknown. During exercise these resistances are reduced by the recruitment of lung capillaries. The factors that reduce the slope of the oxygen dissociation curve of the Hb (ODC) (i.e., lactic acidosis and hyperthermia) increase 1/θVc contributing to limit DLO2. These effects are accentuated in hypoxia. Reducing the size of the active muscle mass improves pulmonary gas exchange during exercise and reduces the rightward shift of the ODC. The flow of oxygen from the muscle capillaries to the mitochondria is pressumably limited by muscle O2 conductance (DmcO2) (an estimation of muscle oxygen diffusing capacity). However, during maximal whole body exercise in normoxia, a higher flow of O2 is achieved at the same pressure gradients after increasing blood [Hb], implying that in healthy humans exercising in normoxia there is a functional reserve in DmcO2. This conclusion is supported by the fact that during small muscle exercise in chronic hypoxia, peak exercise DmcO2 is similar to that observed during exercise in normoxia despite a markedly lower O2 pressure gradient driving diffusion.

Evaluating pulmonary function, aerobic capacity, and pediatric quality of life following a 10-week aerobic exercise training in school-aged asthmatics: a randomized controlled trial.

PubMed

Abdelbasset, Walid K; Alsubaie, Saud F; Tantawy, Sayed A; Abo Elyazed, Tamer I; Kamel, Dalia M

2018-01-01

It has been documented that aerobic exercise may increase pulmonary functions and aerobic capacity, but limited data has evaluated a child's satisfaction and pediatric quality of life (PQoL) with exercise training. This study aimed to investigate the effects of moderate-intensity exercise training on asthmatic school-aged children. This study included 38 school-aged children with asthma (23 males and 15 females) aged between 8-12 years. They were randomly assigned to two groups, aerobic exercise (AE) and conventional treatment (Con ttt) groups. The AE group received a program of moderate-intensity aerobic exercise for 10 weeks with asthma medications and the Con ttt group received only asthma medications without exercise intervention. A home respiratory exercise was recommended for the two groups. Aerobic capacity was investigated using maximal oxygen uptake (VO 2max ), 6-minute walk test (6MWT), and fatigue index. PQoL was evaluated using Pediatric Quality of Life Questionnaire (PQoLQ). Also, pulmonary function tests were performed, and the results recorded. The findings of this study showed significant improvements in pulmonary functions and VO 2max in the two groups; however, this improvement was significantly higher in the AE group than in the Con ttt group ( p <0.05). The 6MWT and fatigue index improved in the AE group ( p <0.05) but not in the Con ttt group ( p >0.05). All dimensions of PQoL significantly improved in the AE group ( p <0.05), but there was no significant improvement in the Con ttt group after the 10-week intervention period ( p >0.05). Ten weeks of physical exercise had beneficial effects on pulmonary functions, aerobic capacity, and PQoL in school-aged children with asthma. Effort and awareness should be dedicated to encouraging the active lifestyle among different populations, especially asthmatic children.

Optimizing functional exercise capacity in the elderly surgical population.

PubMed

Carli, Franco; Zavorsky, Gerald S

2005-01-01

There are several studies on the effect of exercise post surgery (rehabilitation), but few studies have looked at augmenting functional capacity prior to surgical admission (prehabilitation). A programme of prehabilitation is proposed in order to enhance functional exercise capacity in elderly patients with the intent to minimize the postoperative morbidity and accelerate postsurgical recovery. Few studies have looked at exercise prehabilitation to improve functional capacity prior to surgical admission. Prehabilitation prior to orthopaedic surgery does not seem to improve quality of life or recovery. However, prehabilitation prior to abdominal or cardiac surgery, based on 275 elderly patients, results in fewer postoperative complications, shorter postoperative length of stay, improved quality of life, and reduced declines in functional disability compared to sedentary controls. A concentrated 3-month progressive exercise prehabilitation programme consisting of aerobic training at 45-65% of maximal heart rate reserve (%HRR) along with periodic high-intensity interval training ( approximately 90% HRR) four times per week, 30-50 minutes per session, is recommended for improving cardiovascular functioning. A strength training programme of about 10 different exercises focused on large, multi-jointed muscle groups should also be implemented twice per week at a mean training intensity of 80% of one-repetition maximum. Finally, a minimum of 140 g ( approximately 560 kcal) of carbohydrate (CHO) should be taken 3 h before training to increase liver and muscle glycogen stores and a minimum of about 200 kcal of mixed protein-CHO should be ingested within 30 min following training to enhance muscle hypertrophy.

Systemic impairment in relation to disease burden in patients with moderate COPD eligible for a lifestyle program. Findings from the INTERCOM trial

PubMed Central

van Wetering, Carel R; van Nooten, Floortje E; Mol, Stijn J M; Hoogendoorn, Martine; Rutten-van Mölken, Maureen P M H; Schols, Annemie M

2008-01-01

Introduction In contrast with the frequency distribution of chronic obstructive pulmonary disease (COPD) stages in the population, in which the majority of the patients is classified as GOLD 2, much less information is available on the prevalence and implications of systemic manifestations in less severe patients relative to GOLD 3 and 4. Aim To characterize local and systemic impairment in relation to disease burden in a group of GOLD 2 COPD patients (n = 127, forced expiratory volume in one second (SD): 67 (11)% pred) that were eligible for the Interdisciplinary Community-based COPD management (INTERCOM) trial. Methods Patients were included for this lifestyle program based on a peak exercise capacity (Wmax) <70% of predicted. Metabolic and ventilatory response to incremental cycle ergometry, 6 minute walking distance (6MWD), constant work rate test (CWR), lung function, maximal inspiratory pressure (Pimax), quadriceps force (QF), quadriceps average power (QP) (isokinetic dynamometry), handgrip force (HGF) and body composition were measured. Quality of life (QoL) was assessed by the St. George’s Respiratory Questionnaire (SGRQ) and dyspnea by the modified Medical Research Council (MRC) dyspnea scale. Exacerbations and COPD-associated hospital admissions in 12 months prior to the start of the study were recorded. Burden of disease was defined in terms of exercise capacity, QoL, hospitalization, and exacerbation frequency. GOLD 2 patients were compared with reference values and with GOLD 3 patients who were also included in the trial. Results HGF (77.7 (18.8) % pred) and Pimax (67.1 (22.5)% pred) were impaired in GOLD 2, while QF (93.5 (22.5)% pred) was only modestly decreased. Depletion of FFM was present in 15% of weight stable GOLD 2 patients while only 2% had experienced recent involuntary weight loss. In contrast to Wmax, submaximal exercise capacity, muscle function, and body composition were not significantly different between GOLD 2 and 3 subgroups. Body mass index and fat-free mass index were significantly lower in smokers compared to ex-smokers. In multivariate analysis, QF and diffusing capacity (DLco) were independently associated with Wmax and 6 MWD in GOLD 2 while only 6 MWD was identified as an independent determinant of health-related QoL. HGF was an independent predictor of hospitalization. Conclusions This study shows that also in patients with moderate COPD, eligible for a lifestyle program based on a decreased exercise capacity, systemic impairment is an important determinant of disease burden and that smoking affects body composition. PMID:18990973

Diet composition and the performance of high-intensity exercise.

PubMed

Maughan, R J; Greenhaff, P L; Leiper, J B; Ball, D; Lambert, C P; Gleeson, M

1997-06-01

The crucial role of muscle glycogen as a fuel during prolonged exercise is well established, and the effects of acute changes in dietary carbohydrate intake on muscle glycogen content and on endurance capacity are equally well known. More recently, it has been recognized that diet can also affect the performance of high-intensity exercise of short (2-7 min) duration. If the muscle glycogen content is lowered by prolonged (1-1.5 h) exhausting cycle exercise, and is subsequently kept low for 3-4 days by consumption of a diet deficient in carbohydrate (< 5% of total energy intake), there is a dramatic (approximately 10-30%) reduction in exercise capacity during cycling sustainable for about 5 min. The same effect is observed if exercise is preceded by 3-4 days on a carbohydrate-restricted diet or by a 24 h total fast without prior depletion of the muscle glycogen. Consumption of a diet high in carbohydrate (70% of total energy intake from carbohydrate) for 3-4 days before exercise improves exercise capacity during high-intensity exercise, although this effect is less consistent. The blood lactate concentration is always lower at the point of fatigue after a diet low in carbohydrate and higher after a diet high in carbohydrate than after a normal diet. Even when the duration of the exercise task is kept constant, the blood lactate concentration is higher after exercise on a diet high in carbohydrate than on a diet low in carbohydrate. Consumption of a low-carbohydrate isoenergetic diet is achieved by an increased intake of protein and fat. A high-protein diet, particularly when combined with a low carbohydrate intake, results in metabolic acidosis, which ensues within 24 h and persists for at least 4 days. This appears to be the result of an increase in the circulating concentrations of strong organic acids, particularly free fatty acids and 3-hydroxybutyrate, together with an increase in the total plasma protein concentration. This acidosis, rather than any decrease in the muscle glycogen content, may be responsible for the reduced exercise capacity in high-intensity exercise; this may be due to a reduced rate of efflux of lactate and hydrogen ions from the working muscles. Alternatively, the accumulation of acetyl groups in the carbohydrate-deprived state may reduce substrate flux through the pyruvate dehydrogenase complex, thus reducing aerobic energy supply and accelerating the onset of fatigue.

Exercise-induced oxyhaemoglobin desaturation, ventilatory limitation and lung diffusing capacity in women during and after exercise.

PubMed

Walls, Justin; Maskrey, Michael; Wood-Baker, Richard; Stedman, Wade

2002-06-01

Arterial haemoglobin saturation during exercise in healthy young women [eight subjects mean (SEM) age 20.8 (1.8) years] was measured to confirm the theory that young women experience exercise-induced arterial hypoxaemia (EIAH) at a lower relative percentage of maximal oxygen uptake (VO(2max)) than has been documented in their male counterparts. To determine if flow limitation [the percentage of the tidal volume ( V(T)) that met or exceeded the boundary established by multiple maximal expiratory manoeuvres] and/or post-exercise lung diffusing capacity are linked to EIAH in women, and to investigate the influence of exercise intensity and duration on post-exercise carbon monoxide lung diffusing capacity ( D(L, CO)), these parameters were measured during and after three exercise tests (incremental test until exhaustion, 5 km run and 5 km run with sprint). All subjects experienced physiologically significant EIAH (a fall of more than 3% in oxygen saturation of arterial blood from levels at rest) and seven subjects experienced flow limitation during the VO(2max) protocol [mean (SD) 12.2 (8.8)% of V(T)]. Even though there was no significant relationship between aerobic capacity and the degree of flow limitation ( r=0.33, P>0.05), the flow limitation was related to absolute ventilation in the subjects studied ( r=0.82, P<0.05). There was no significant relationship between decrements in post exercise D(L, CO) and EIAH ( r=0.05, P>0.05), however there was a strong correlation between the extent of flow limitation (% of V(T)) and EIAH ( r=0.71). Significant decreases in D(L, CO) lasted for up to 16 h after each of the exercise tests ( P<0.05) and lasted for a further 8 h after the maximal test ( P<0.05). Exercise intensity was the main contributing factor to the observed decreases in post-exercise D(L, CO) with the percentage of VO(2max) attained during the various tests being significantly related to the fall in D(L, CO) for 1, 2, 3, 16 and 24 h after exercise ( P<0.05). As the appearance of flow limitation closely coincided with the appearance of EIAH, the results from the present study suggest that flow limitation is a contributing factor to EIAH in women although the exact mechanism remains unclear.

Improvements in exercise performance with high-intensity interval training coincide with an increase in skeletal muscle mitochondrial content and function.

PubMed

Jacobs, Robert Acton; Flück, Daniela; Bonne, Thomas Christian; Bürgi, Simon; Christensen, Peter Møller; Toigo, Marco; Lundby, Carsten

2013-09-01

Six sessions of high-intensity interval training (HIT) are sufficient to improve exercise capacity. The mechanisms explaining such improvements are unclear. Accordingly, the aim of this study was to perform a comprehensive evaluation of physiologically relevant adaptations occurring after six sessions of HIT to determine the mechanisms explaining improvements in exercise performance. Sixteen untrained (43 ± 6 ml·kg(-1)·min(-1)) subjects completed six sessions of repeated (8-12) 60 s intervals of high-intensity cycling (100% peak power output elicited during incremental maximal exercise test) intermixed with 75 s of recovery cycling at a low intensity (30 W) over a 2-wk period. Potential training-induced alterations in skeletal muscle respiratory capacity, mitochondrial content, skeletal muscle oxygenation, cardiac capacity, blood volumes, and peripheral fatigue resistance were all assessed prior to and again following training. Maximal measures of oxygen uptake (Vo2peak; ∼8%; P = 0.026) and cycling time to complete a set amount of work (∼5%; P = 0.008) improved. Skeletal muscle respiratory capacities increased, most likely as a result of an expansion of skeletal muscle mitochondria (∼20%, P = 0.026), as assessed by cytochrome c oxidase activity. Skeletal muscle deoxygenation also increased while maximal cardiac output, total hemoglobin, plasma volume, total blood volume, and relative measures of peripheral fatigue resistance were all unaltered with training. These results suggest that increases in mitochondrial content following six HIT sessions may facilitate improvements in respiratory capacity and oxygen extraction, and ultimately are responsible for the improvements in maximal whole body exercise capacity and endurance performance in previously untrained individuals.

Rationale and design of a trial on the role of bosentan in Fontan patients: improvement of exercise capacity?

PubMed

Schuuring, Mark J; Vis, Jeroen C; Bouma, Berto J; van Dijk, Arie P J; van Melle, Joost P; Pieper, Petronella G; Vliegen, Hubert W; Sieswerda, Gertjan Tj; Mulder, Barbara J M

2011-07-01

The Fontan circulation is a palliative procedure performed in patients with complex congenital heart disease (CHD), making transpulmonary blood flow dependent on the systemic venous pressure. In a Fontan circulation a low pulmonary vascular resistance (PVR) is crucial, as is epitomized by the observation that a high PVR is a strong predictor of mortality. Long-term follow-up has shown that PVR may rise many years after the Fontan procedure has been performed, possibly due to micro-emboli from a dilated right atrium or from the venous system. Other mechanisms of increased PVR might be aging, obstructed airways caused by lymphatic dysfunction, lack of pulsatile pulmonary flow causing a release of endothelium-derived vasoactive molecules, and prolonged overexpression of vasoconstrictors such as endothelin-1. Mean plasma level of endothelin-1 has been shown to be significantly higher in Fontan patients compared to healthy controls. In patients with pulmonary arterial hypertension (PAH), therapy with bosentan, an endothelin-1 receptor antagonist, has demonstrated to improve exercise capacity and to reduce the elevated PVR. In addition, reduction of PVR is shown early and late after the Fontan procedure on treatment with exogenous NO, another advanced PAH therapy. However, the long term effect of reducing the PVR by bosentan treatment on exercise capacity in Fontan patients is still unknown. We designed a prospective, multicenter, randomized open label trial to study the effect of bosentan in Fontan patients. The primary endpoint will be the change in maximum exercise capacity (peak V'O2). We hypothesize that treatment with bosentan, an endothelin-1 receptor antagonist, improves maximum exercise capacity and functional capacity in adult Fontan patients. Copyright © 2011 Elsevier Inc. All rights reserved.

Nutritional status, functional capacity and exercise rehabilitation in end-stage renal disease.

PubMed

Mercer, T H; Koufaki, P; Naish, P F

2004-05-01

A significant percentage of patients with end-stage renal disease are malnourished and/or muscle wasted. Uremia is associated with decreased protein synthesis and increased protein degradation. Fortunately, nutritional status has been shown to be a modifiable risk factor in the dialysis population. It has long been proposed that exercise could positively alter the protein synthesis-degradation balance. Resistance training had been considered as the only form of exercise likely to induce anabolism in renal failure patients. However, a small, but growing, body of evidence indicates that for some dialysis patients, favourable improvements in muscle atrophy and fibre hypertrophy can be achieved via predominantly aerobic exercise training. Moreover, some studies tentatively suggest that nutritional status, as measured by SGA, can also be modestly improved by modes and patterns of exercise training that have been shown to also increase muscle fibre cross-sectional area and improve functional capacity. Functional capacity tests can augment the information content of basic nutritional status assessments of dialysis patients and as such are recommended for routine inclusion as a feature of all nutritional status assessments.

Subclinical cardiopulmonary dysfunction in stage 3 chronic kidney disease.

PubMed

Nelson, Alexander; Otto, James; Whittle, John; Stephens, Robert C M; Martin, Daniel S; Prowle, John R; Ackland, Gareth L

2016-01-01

Reduced exercise capacity is well documented in end-stage chronic kidney disease (CKD), preceded by changes in cardiac morphology in CKD stage 3. However, it is unknown whether subclinical cardiopulmonary dysfunction occurs in CKD stage 3 independently of heart failure. Prospective observational cross-sectional study of exercise capacity assessed by cardiopulmonary exercise testing in 993 preoperative patients. Primary outcome was peak oxygen consumption (VO2peak). Anaerobic threshold (AT), oxygen pulse and exercise-evoked measures of autonomic function were analysed, controlling for CKD stage 3, age, gender, diabetes mellitus and hypertension. CKD stage 3 was present in 93/993 (9.97%) patients. Diabetes mellitus (RR 2.49 (95% CI 1.59 to 3.89); p<0.001), and hypertension (RR 3.20 (95% CI 2.04 to 5.03); p<0.001)) were more common in CKD stage 3. Cardiac failure (RR 0.83 (95% CI 0.30 to 2.24); p=0.70) and ischaemic heart disease (RR 1.40 (95% CI 0.97 to 2.02); p=0.09) were not more common in CKD stage 3. Patients with CKD stage 3 had lower predicted VO2peak (mean difference: 6% (95% CI 1% to 11%); p=0.02), lower peak heart rate (mean difference:9 bpm (95% CI 3 to 14); p=0.03)), lower AT (mean difference: 1.1 mL/min/kg (95% CI 0.4 to 1.7); p<0.001) and impaired heart rate recovery (mean difference: 4 bpm (95% CI 1 to 7); p<0.001)). Subclinical cardiopulmonary dysfunction in CKD stage 3 is common. This study suggests that maladaptive cardiovascular/autonomic dysfunction may be established in CKD stage 3, preceding pathophysiology reported in end-stage CKD.

Multicenter study of pectus excavatum, final report: complications, static/exercise pulmonary function, and anatomic outcomes.

PubMed

Kelly, Robert E; Mellins, Robert B; Shamberger, Robert C; Mitchell, Karen K; Lawson, M Louise; Oldham, Keith T; Azizkhan, Richard G; Hebra, Andre V; Nuss, Donald; Goretsky, Michael J; Sharp, Ronald J; Holcomb, George W; Shim, Walton K T; Megison, Stephen M; Moss, R Lawrence; Fecteau, Annie H; Colombani, Paul M; Cooper, Dan; Bagley, Traci; Quinn, Amy; Moskowitz, Alan B; Paulson, James F

2013-12-01

A multicenter study of pectus excavatum was described previously. This report presents our final results. Patients treated surgically at 11 centers were followed prospectively. Each underwent a preoperative evaluation with CT scan, pulmonary function tests, and body image survey. Data were collected about associated conditions, complications, and perioperative pain. One year after treatment, patients underwent repeat chest CT scan, pulmonary function tests, and body image survey. A subset of 50 underwent exercise pulmonary function testing. Of 327 patients, 284 underwent Nuss procedure and 43 underwent open procedure without mortality. Of 182 patients with complete follow-up (56%), 18% had late complications, similarly distributed, including substernal bar displacement in 7% and wound infection in 2%. Mean initial CT scan index of 4.4 improved to 3.0 post operation (severe >3.2, normal = 2.5). Computed tomography index improved at the deepest point (xiphoid) and also upper and middle sternum. Pulmonary function tests improved (forced vital capacity from 88% to 93%, forced expiratory volume in 1 second from 87% to 90%, and total lung capacity from 94% to 100% of predicted (p < 0.001 for each). VO2 max during peak exercise increased by 10.1% (p = 0.015) and O2 pulse by 19% (p = 0.007) in 20 subjects who completed both pre- and postoperative exercise tests. There is significant improvement in lung function at rest and in VO2 max and O2 pulse after surgical correction of pectus excavatum, with CT index >3.2. Operative correction significantly reduces CT index and markedly improves the shape of the entire chest, and can be performed safely in a variety of centers. Copyright © 2013 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Water-based exercise training for chronic obstructive pulmonary disease.

PubMed

McNamara, Renae J; McKeough, Zoe J; McKenzie, David K; Alison, Jennifer A

2013-12-18

Land-based exercise training improves exercise capacity and quality of life in people with chronic obstructive pulmonary disease (COPD). Water-based exercise training is an alternative mode of physical exercise training that may appeal to the older population attending pulmonary rehabilitation programmes, those who are unable to complete land-based exercise programmes and people with COPD with comorbid physical and medical conditions. To assess the effects of water-based exercise training in people with COPD. A search of the Cochrane Airways Group Specialised Register of trials, which is derived from systematic searches of bibliographic databases, including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL, AMED and PsycINFO, was conducted (from inception to August 2013). Handsearching was done to identify further qualifying studies from reference lists of relevant studies. Review authors included randomised or quasi-randomised controlled trials in which water-based exercise training of at least four weeks' duration was compared with no exercise training or any other form of exercise training in people with COPD. Swimming was excluded. We used standard methodological procedures expected by The Cochrane Collaboration. Five studies were included with a total of 176 participants (71 people participated in water-based exercise training and 54 in land-based exercise training; 51 completed no exercise training). All studies compared supervised water-based exercise training versus land-based exercise training and/or no exercise training in people with COPD (with average forced expiratory volume in one second (FEV1) %predicted ranging from 39% to 62%). Sample sizes ranged from 11 to 53 participants. The exercise training programmes lasted from four to 12 weeks, and the mean age of participants ranged from 57 to 73 years. A moderate risk of bias was due to lack of reporting of randomisation, allocation and blinding procedures in some studies, as well as small sample sizes.Compared with no exercise, water-based exercise training improved the six-minute walk distance (mean difference (MD) 62 metres; 95% confidence interval (CI) 44 to 80 metres; three studies; 99 participants; moderate quality evidence), the incremental shuttle walk distance (MD 50 metres; 95% CI 20 to 80 metres; one study; 30 participants; high quality evidence) and the endurance shuttle walk distance (MD 371 metres; 95% CI 121 to 621 metres; one study; 30 participants; high quality evidence). Quality of life was also improved after water-based exercise training compared with no exercise (standardised mean difference (SMD) -0.97, 95% CI -0.37 to -1.57; two studies; 49 participants; low quality evidence). Compared with land-based exercise training, water-based exercise training did not significantly change the six-minute walk distance (MD 11 metres; 95% CI -11 to 33 metres; three studies; 62 participants; moderate quality evidence) or the incremental shuttle walk distance (MD 9 metres; 95% CI -15 to 34 metres; two studies; 59 participants; low quality evidence). However, the endurance shuttle walk distance improved following water-based exercise training compared with land-based exercise training (MD 313 metres; 95% CI 232 to 394 metres; two studies; 59 participants; moderate quality evidence). No significant differences were found between water-based exercise training and land-based exercise training for quality of life, as measured by the St George's Respiratory Questionnaire or by three of four domains of the Chronic Respiratory Disease Questionnaire (CRDQ); however, the fatigue domain of the CRDQ showed a statistically significant difference in favour of water-based exercise (MD -3.00; 95% CI -5.26 to -0.74; one study; 30 participants). Only one study reported long-term outcomes after water-based exercise training for quality of life and body composition, and no significant change was observed between baseline results and six-month follow-up results. One minor adverse event was reported for water-based exercise training (based on reporting from two studies; 20 participants). Impact of disease severity could not be examined because data were insufficient. There is limited quality evidence that water-based exercise training is safe and improves exercise capacity and quality of life in people with COPD immediately after training. There is limited quality evidence that water-based exercise training offers advantages over land-based exercise training in improving endurance exercise capacity, but we remain uncertain as to whether it leads to better quality of life. Little evidence exists examining the long-term effect of water-based exercise training.

Exercise for Those with Chronic Heart Failure: Matching Programs to Patients.

ERIC Educational Resources Information Center

Braith, Randy W.

2002-01-01

Exercise training increases functional capacity and improves symptoms in selected patients with chronic heart failure and moderate-to-severe left ventricular systolic dysfunction. Aerobic training forms the basis of such a program. This paper describes contributors to exercise intolerance, responses to exercise training, favorable outcomes with…

Exercise Programming for Cardiacs--A New Direction for Physical Therapists.

ERIC Educational Resources Information Center

Gutin, Bernard

This speech begins with the presentation of a conceptual scheme of the physical working capacity of a person starting a training program. The scheme shows that after exercise, when recovery begins and sufficient time elapses, the individual recovers and adapts to a level of physical working capacity which is higher than his starting level. From…

Can a Home-based Cardiac Physical Activity Program Improve the Physical Function Quality of Life in Children with Fontan Circulation?

PubMed

Jacobsen, Roni M; Ginde, Salil; Mussatto, Kathleen; Neubauer, Jennifer; Earing, Michael; Danduran, Michael

2016-01-01

Patients after Fontan operation for complex congenital heart disease (CHD) have decreased exercise capacity and report reduced health-related quality of life (HRQOL). Studies suggest hospital-based cardiac physical activity programs can improve HRQOL and exercise capacity in patients with CHD; however, these programs have variable adherence rates. The impact of a home-based cardiac physical activity program in Fontan survivors is unclear. This pilot study evaluated the safety, feasibility, and benefits of an innovative home-based physical activity program on HRQOL in Fontan patients. A total of 14 children, 8-12 years, with Fontan circulation enrolled in a 12-week moderate/high intensity home-based cardiac physical activity program, which included a home exercise routine and 3 formalized in-person exercise sessions at 0, 6, and 12 weeks. Subjects and parents completed validated questionnaires to assess HRQOL. The Shuttle Test Run was used to measure exercise capacity. A Fitbit Flex Activity Monitor was used to assess adherence to the home activity program. Of the 14 patients, 57% were male and 36% had a dominant left ventricle. Overall, 93% completed the program. There were no adverse events. Parents reported significant improvement in their child's overall HRQOL (P < .01), physical function (P < .01), school function (P = .01), and psychosocial function (P < .01). Patients reported no improvement in HRQOL. Exercise capacity, measured by total shuttles and exercise time in the Shuttle Test Run and calculated VO2 max, improved progressively from baseline to the 6 and 12 week follow up sessions. Monthly Fitbit data suggested adherence to the program. This 12-week home-based cardiac physical activity program is safe and feasible in preteen Fontan patients. Parent proxy-reported HRQOL and objective measures of exercise capacity significantly improved. A 6-month follow up session is scheduled to assess sustainability. A larger study is needed to determine the applicability and reproducibility of these findings in other age groups and forms of complex CHD. © 2016 Wiley Periodicals, Inc.

The Role of Exercise in Cardiac Aging: From Physiology to Molecular Mechanisms

PubMed Central

Roh, Jason; Rhee, James; Chaudhari, Vinita; Rosenzweig, Anthony

2015-01-01

Aging induces structural and functional changes in the heart that are associated with increased risk of cardiovascular disease and impaired functional capacity in the elderly. Exercise is a diagnostic and therapeutic tool, with the potential to provide insights into clinical diagnosis and prognosis, as well as the molecular mechanisms by which aging influences cardiac physiology and function. In this review, we first provide an overview of how aging impacts the cardiac response to exercise and the implications this has for functional capacity in older adults. We then review the underlying molecular mechanisms by which cardiac aging contributes to exercise intolerance, and conversely how exercise training can potentially modulate aging phenotypes in the heart. Finally, we highlight the potential use of these exercise models to complement models of disease in efforts to uncover new therapeutic targets to prevent or treat heart disease in the aging population. PMID:26838314

The Role of Exercise in Cardiac Aging: From Physiology to Molecular Mechanisms.

PubMed

Roh, Jason; Rhee, James; Chaudhari, Vinita; Rosenzweig, Anthony

2016-01-22

Aging induces structural and functional changes in the heart that are associated with increased risk of cardiovascular disease and impaired functional capacity in the elderly. Exercise is a diagnostic and therapeutic tool, with the potential to provide insights into clinical diagnosis and prognosis, as well as the molecular mechanisms by which aging influences cardiac physiology and function. In this review, we first provide an overview of how aging impacts the cardiac response to exercise, and the implications this has for functional capacity in older adults. We then review the underlying molecular mechanisms by which cardiac aging contributes to exercise intolerance, and conversely how exercise training can potentially modulate aging phenotypes in the heart. Finally, we highlight the potential use of these exercise models to complement models of disease in efforts to uncover new therapeutic targets to prevent or treat heart disease in the aging population. © 2016 American Heart Association, Inc.

Exercise in space: the European Space Agency approach to in-flight exercise countermeasures for long-duration missions on ISS.

PubMed

Petersen, Nora; Jaekel, Patrick; Rosenberger, Andre; Weber, Tobias; Scott, Jonathan; Castrucci, Filippo; Lambrecht, Gunda; Ploutz-Snyder, Lori; Damann, Volker; Kozlovskaya, Inessa; Mester, Joachim

2016-01-01

To counteract microgravity (µG)-induced adaptation, European Space Agency (ESA) astronauts on long-duration missions (LDMs) to the International Space Station (ISS) perform a daily physical exercise countermeasure program. Since the first ESA crewmember completed an LDM in 2006, the ESA countermeasure program has strived to provide efficient protection against decreases in body mass, muscle strength, bone mass, and aerobic capacity within the operational constraints of the ISS environment and the changing availability of on-board exercise devices. The purpose of this paper is to provide a description of ESA's individualised approach to in-flight exercise countermeasures and an up-to-date picture of how exercise is used to counteract physiological changes resulting from µG-induced adaptation. Changes in the absolute workload for resistive exercise, treadmill running and cycle ergometry throughout ESA's eight LDMs are also presented, and aspects of pre-flight physical preparation and post-flight reconditioning outlined. With the introduction of the advanced resistive exercise device (ARED) in 2009, the relative contribution of resistance exercise to total in-flight exercise increased (33-46 %), whilst treadmill running (42-33 %) and cycle ergometry (26-20 %) decreased. All eight ESA crewmembers increased their in-flight absolute workload during their LDMs for resistance exercise and treadmill running (running speed and vertical loading through the harness), while cycle ergometer workload was unchanged across missions. Increased or unchanged absolute exercise workloads in-flight would appear contradictory to typical post-flight reductions in muscle mass and strength, and cardiovascular capacity following LDMs. However, increased absolute in-flight workloads are not directly linked to changes in exercise capacity as they likely also reflect the planned, conservative loading early in the mission to allow adaption to µG exercise, including personal comfort issues with novel exercise hardware (e.g. the treadmill harness). Inconsistency in hardware and individualised support concepts across time limit the comparability of results from different crewmembers, and questions regarding the difference between cycling and running in µG versus identical exercise here on Earth, and other factors that might influence in-flight exercise performance, still require further investigation.

No effect of group-based aerobic interval training on N-terminal pro- B-type natriuretic peptide levels in patients with chronic heart failure.

PubMed

Nilsson, Birgitta Blakstad; Westheim, Arne; Risberg, May Arna; Arnesen, Harald; Seljeflot, Ingebjørg

2010-08-01

Exercise training might improve cardiac function as well as functional capacity in patients with chronic heart failure (CHF). N-terminal pro-B-type natriuretic peptide (NT pro-BNP), is associated with the severity of the disease, and has been reported to be an independent predictor of outcome in CHF. We evaluated the effect of a four months group-based aerobic interval training program on circulating levels of NT pro-BNP in patients with CHF. We have previously reported improved functional capacity in 80 patients after exercise in this exercise program. Seventy-eight patients with stable CHF (21% women; 70+/-8 years; left ventricular ejection fraction 30+/-8.6%) on optimal medical treatment were randomized either to interval training (n=39), or to a control group (n=39). Circulating levels of NT pro-BNP, a six minute walk test (6MWT) and cycle ergometer test were evaluated at baseline, post exercise, and further after 12 months. There were no significant differences in NT pro-BNP levels from baseline to either post exercise or long-term follow-up between or within the groups. Inverse correlations were observed between NT pro-BNP and 6MWT (r=-0.24, p=0.035) and cycle exercise time (r=-0.48, p<0.001) at baseline. But no significant correlations were observed between change in NT pro-BNP and change in functional capacity (6MWT; r=0.12, p=0.33, cycle exercise time; r=0.04, p=0.72). No significant changes in NT pro-BNP levels were observed after interval training, despite significant improvement of functional capacity.

The Impact of a Multidimensional Exercise Intervention on Physical and Functional Capacity, Anxiety, and Depression in Patients With Advanced-Stage Lung Cancer Undergoing Chemotherapy.

PubMed

Quist, Morten; Adamsen, Lis; Rørth, Mikael; Laursen, Jørgen H; Christensen, Karl B; Langer, Seppo W

2015-07-01

Patients with advanced-stage lung cancer face poor survival and experience co-occurring chronic physical and psychosocial symptoms. Despite several years of research in exercise oncology, few exercise studies have targeted advanced lung cancer patients undergoing chemotherapy. The aim of the present study was to investigate the benefits of a 6-week supervised group exercise intervention and to outline the effect on aerobic capacity, strength, health-related quality of life (HRQoL), anxiety, and depression. VO2peak was assessed using an incremental exercise test. Muscle strength was measured with one repetition maximum test (1RM). HRQoL, anxiety, and depression were assessed using Functional Assessment of Cancer Therapy-Lung (FACT-L) scale and the Hospital Anxiety and Depression Scale (HADS). One hundred and forthteen patients with advanced stage lung cancer were recruited. Forty-three patients dropped out. No serious adverse events were reported. Exercise adherence in the group training was 68%. Improvements in VO2peak (P < .001) and 6-minute walk distance (P < .001) and muscle strength measurements (P < .05) were seen. There was a reduction in anxiety level (P = .0007) and improvement in the emotional well-being parameter (FACT-L) but no statistically significant changes in HRQoL were observed. The results of the present study show that during a 6-week hospital-based supervised, structured, and group-based exercise program, patients with advanced-stage lung cancer (NSCLC IIIb-IV, ED-SCLC) improve their physical capacity (VO2peak, 1RM), functional capacity, anxiety level, and emotional well-being, but not their overall HRQoL. A randomized controlled trial testing the intervention including 216 patients is currently being carried out. © The Author(s) 2015.

Mitochondrial and performance adaptations to exercise training in mice lacking skeletal muscle LKB1

PubMed Central

Tanner, Colby B.; Madsen, Steven R.; Hallowell, David M.; Goring, Darren M. J.; Moore, Timothy M.; Hardman, Shalene E.; Heninger, Megan R.; Atwood, Daniel R.

2013-01-01

LKB1 and its downstream targets of the AMP-activated protein kinase family are important regulators of many aspects of skeletal muscle cell function, including control of mitochondrial content and capillarity. LKB1 deficiency in skeletal and cardiac muscle (mLKB1-KO) greatly impairs exercise capacity. However, cardiac dysfunction in that genetic model prevents a clear assessment of the role of skeletal muscle LKB1 in the observed effects. Our purposes here were to determine whether skeletal muscle-specific knockout of LKB1 (skmLKB1-KO) decreases exercise capacity and mitochondrial protein content, impairs accretion of mitochondrial proteins after exercise training, and attenuates improvement in running performance after exercise training. We found that treadmill and voluntary wheel running capacity was reduced in skmLKB1-KO vs. control (CON) mice. Citrate synthase activity, succinate dehydrogenase activity, and pyruvate dehydrogenase kinase content were lower in KO vs. CON muscles. Three weeks of treadmill training resulted in significantly increased treadmill running performance in both CON and skmLKB1-KO mice. Citrate synthase activity increased significantly with training in both genotypes, but protein content and activity for components of the mitochondrial electron transport chain increased only in CON mice. Capillarity and VEGF protein was lower in skmLKB1-KO vs. CON muscles, but VEGF increased with training only in skmLKB1-KO. Three hours after an acute bout of muscle contractions, PGC-1α, cytochrome c, and VEGF gene expression all increased in CON but not skmLKB1-KO muscles. Our findings indicate that skeletal muscle LKB1 is required for accretion of some mitochondrial proteins but not for early exercise capacity improvements with exercise training. PMID:23982155

Cardiopulmonary exercise testing to evaluate the exercise capacity of patients with inoperable chronic thromboembolic pulmonary hypertension: an endothelin receptor antagonist improves the peak PETCO2.

PubMed

Hirashiki, Akihiro; Adachi, Shiro; Nakano, Yoshihisa; Kono, Yuji; Shimazu, Shuzo; Shimizu, Shinya; Morimoto, Ryota; Okumura, Takahiro; Takeshita, Kyosuke; Yamada, Sumio; Murohara, Toyoaki; Kondo, Takahisa

2014-11-24

The 6-min walking distance is often used for assessing the exercise capacity under the treatment with an endothelin receptor antagonist (ERA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). The cardiopulmonary exercise testing (CPX) was reported to be more useful for the patients with pulmonary arterial hypertension (PAH), however, few reports exist in patients with inoperable CTEPH. The aim of this study was to investigate the effects of an oral dual ERA, bosentan, on exercise capacity using CPX in patients with PAH and inoperable CTEPH. This study included all patients diagnosed with 17 PAH and 12 CTEPH in the World Health Organization functional classes II-IV who started treatment with bosentan therapy. They underwent CPX, which was performed before bosentan therapy and at 3 to 6 months of the treatment. In PAH patients, peak VO2 significantly increased after the bosentan treatment (p=0.009). On the other hand, in CTEPH patients, there were no significant differences in the peak VO2. However, the peak PETCO2 was significantly increased from 23.9±5.2 mm Hg at baseline to 29.3±10.7 mm Hg after the bosentan treatment (p=0.040). In addition, peak heart rate during exercise tended to decrease after the bosentan therapy (p=0.089). Bosentan therapy improved peak PETCO2 but not peak VO2 in patients with inoperable CTEPH. These findings demonstrated that CPX is useful for assessing the exercise capacity of patients with PAH and inoperable CTEPH under the treatment with an ERA. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Acute effects of intradialytic aerobic exercise on solute removal, blood gases and oxidative stress in patients with chronic kidney disease.

PubMed

Böhm, Joseane; Monteiro, Mariane Borba; Andrade, Francini Porcher; Veronese, Francisco Veríssimo; Thomé, Fernando Saldanha

2017-01-01

Hemodialysis contributes to increased oxidative stress and induces transitory hypoxemia. Compartmentalization decreases the supply of solutes to the dialyzer during treatment. The aim of this study was to investigate the acute effects of intradialytic aerobic exercise on solute removal, blood gases and oxidative stress in patients with chronic kidney disease during a single hemodialysis session. Thirty patients were randomized to perform aerobic exercise with cycle ergometer for lower limbs during 30 minutes with intensity between 60-70% of maximal heart rate, or control group (CG). Blood samples were collected prior to and immediately after exercise or the equivalent time in CG. Analysis of blood and dialysate biochemistry as well as blood gases were performed. Mass removal and solute clearance were calculated. Oxidative stress was determined by lipid peroxidation and by the total antioxidant capacity. Serum concentrations of solutes increased with exercise, but only phosphorus showed a significant elevation (p = 0.035). There were no significant changes in solute removal and in the acid-base balance. Both oxygen partial pressure and saturation increased with exercise (p = 0.035 and p = 0.024, respectivelly), which did not occur in the CG. The total antioxidant capacity decreased significantly (p = 0.027). The acute intradialytic aerobic exercise increased phosphorus serum concentration and decreased total antioxidant capacity, reversing hypoxemia resulting from hemodialysis. The intradialytic exercise did not change the blood acid-base balance and the removal of solutes.

Exercise interventions in polypathological aging patients that coexist with diabetes mellitus: improving functional status and quality of life.

PubMed

Cadore, Eduardo Lusa; Izquierdo, Mikel

2015-06-01

In elderly populations, diabetes is associated with reduced muscle strength, poor muscle quality, and accelerated loss of muscle mass. In addition, diabetes mellitus increases risk for accelerated aging and for the development of frailty syndrome. This disease is also associated with a polypathological condition, and its complications progressively affect quality of life and survival. Exercise interventions, including resistance training, represent the cornerstones of diabetes management, especially in patients at severe functional decline. This review manuscript aimed to describe the beneficial effects of different exercise interventions on the functional capacity of elderly diabetics, including those at polypathological condition. The SciELO, Science Citation Index, MEDLINE, Scopus, SPORTDiscus, and ScienceDirect databases were searched from 1980 to 2015 for articles published from original scientific investigations. In addition to the beneficial effects of exercise interventions on glycemic control, and on the cardiovascular risk factors associated with diabetes, physical exercise is an effective intervention to improve muscle strength, power output, and aerobic power and functional capacity in elderly diabetic patients. Thus, a combination of resistance and endurance training is the most effective exercise intervention to promote overall physical fitness in these patients. In addition, in diabetic patients with frailty and severe functional decline, a multicomponent exercise program including strength and power training, balance exercises, and gait retraining may be an effective intervention to reduce falls and improve functional capacity and quality of life in these patients.

Regulation of fuel metabolism during exercise in hypopituitarism with growth hormone-deficiency (GHD).

PubMed

Zueger, Thomas; Loher, Hannah; Egger, Andrea; Boesch, Chris; Christ, Emanuel

2016-08-01

Growth hormone (GH) has a strong lipolytic action and its secretion is increased during exercise. Data on fuel metabolism and its hormonal regulation during prolonged exercise in patients with growth hormone deficiency (GHD) is scarce. This study aimed at evaluating the hormonal and metabolic response during aerobic exercise in GHD patients. Ten patients with confirmed GHD and 10 healthy control individuals (CI) matched for age, sex, BMI, and waist performed a spiroergometric test to determine exercise capacity (VO2max). Throughout a subsequent 120-minute exercise on an ergometer at 50% of individual VO2max free fatty acids (FFA), glucose, GH, cortisol, catecholamines and insulin were measured. Additionally substrate oxidation assessed by indirect calorimetry was determined at begin and end of exercise. Exercise capacity was lower in GHD compared to CI (VO2max 35.5±7.4 vs 41.5±5.5ml/min∗kg, p=0.05). GH area under the curve (AUC-GH), peak-GH and peak-FFA were lower in GHD patients during exercise compared to CI (AUC-GH 100±93.2 vs 908.6±623.7ng∗min/ml, p<0.001; peak-GH 1.5±1.53 vs 12.57±9.36ng/ml, p<0.001, peak-FFA 1.01±0.43 vs 1.51±0.56mmol/l, p=0.036, respectively). There were no significant differences for insulin, cortisol, catecholamines and glucose. Fat oxidation at the end of exercise was higher in CI compared to GHD patients (295.7±73.9 vs 187.82±103.8kcal/h, p=0.025). A reduced availability of FFA during a 2-hour aerobic exercise and a reduced fat oxidation at the end of exercise may contribute to the decreased exercise capacity in GHD patients. Catecholamines and cortisol do not compensate for the lack of the lipolytic action of GH in patients with GHD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Is exercise training safe and beneficial in patients receiving left ventricular assist device therapy?

PubMed

Alsara, Osama; Perez-Terzic, Carmen; Squires, Ray W; Dandamudi, Sanjay; Miranda, William R; Park, Soon J; Thomas, Randal J

2014-01-01

Because a limited number of patients receive heart transplantation, alternative therapies, such as left ventricular assist device (LVAD) therapy, have emerged. Published studies have shown that LVAD implantation, by itself, improves exercise tolerance to the point where it is comparable to those with mild heart failure. The improvement in exercise capacity is maximally achieved 12 weeks after LVAD therapy and can continue even after explantation of the device. This effect varies, depending on the type of LVAD and exercise training. The available data in the literature on safety and benefits of exercise training in patients after LVAD implantation are limited, but the data that are available suggest that training trends to be safe and have an impact on exercise capacity in LVAD patients. Although no studies were identified on the role of cardiac rehabilitation programs in the management of LVAD patients, it appears that cardiac rehabilitation programs offer an ideal setting for the provision of supervised exercise training in this patient group.

"Nutraceuticals" in relation to human skeletal muscle and exercise.

PubMed

Deane, Colleen S; Wilkinson, Daniel J; Phillips, Bethan E; Smith, Kenneth; Etheridge, Timothy; Atherton, Philip J

2017-04-01

Skeletal muscles have a fundamental role in locomotion and whole body metabolism, with muscle mass and quality being linked to improved health and even lifespan. Optimizing nutrition in combination with exercise is considered an established, effective ergogenic practice for athletic performance. Importantly, exercise and nutritional approaches also remain arguably the most effective countermeasure for muscle dysfunction associated with aging and numerous clinical conditions, e.g., cancer cachexia, COPD, and organ failure, via engendering favorable adaptations such as increased muscle mass and oxidative capacity. Therefore, it is important to consider the effects of established and novel effectors of muscle mass, function, and metabolism in relation to nutrition and exercise. To address this gap, in this review, we detail existing evidence surrounding the efficacy of a nonexhaustive list of macronutrient, micronutrient, and "nutraceutical" compounds alone and in combination with exercise in relation to skeletal muscle mass, metabolism (protein and fuel), and exercise performance (i.e., strength and endurance capacity). It has long been established that macronutrients have specific roles and impact upon protein metabolism and exercise performance, (i.e., protein positively influences muscle mass and protein metabolism), whereas carbohydrate and fat intakes can influence fuel metabolism and exercise performance. Regarding novel nutraceuticals, we show that the following ones in particular may have effects in relation to 1 ) muscle mass/protein metabolism: leucine, hydroxyl β-methylbutyrate, creatine, vitamin-D, ursolic acid, and phosphatidic acid; and 2 ) exercise performance: (i.e., strength or endurance capacity): hydroxyl β-methylbutyrate, carnitine, creatine, nitrates, and β-alanine. Copyright © 2017 the American Physiological Society.

Short Communication: HIV Patient Systemic Mitochondrial Respiration Improves with Exercise.

PubMed

Kocher, Morgan; McDermott, Mindy; Lindsey, Rachel; Shikuma, Cecilia M; Gerschenson, Mariana; Chow, Dominic C; Kohorn, Lindsay B; Hetzler, Ronald K; Kimura, Iris F

2017-10-01

In HIV-infected individuals, impaired mitochondrial function may contribute to cardiometabolic disease as well as to fatigue and frailty. Aerobic exercise improves total body energy reserves; however, its impact at the cellular level is unknown. We assessed alterations in cellular bioenergetics in peripheral blood mononuclear cells (PBMC) before and after a 12-week aerobic exercise study in sedentary HIV-infected subjects on stable antiretroviral therapy who successfully completed a 12-week aerobic exercise program. In this prospective study, participants underwent supervised 20-40 min of light aerobic exercise (walking or jogging) performed three times per week for 12 weeks, gradually increasing to maintain an intensity of 50%-80% of heart rate reserve. Maximal aerobic capacity (VO 2MAX ) was assessed by a graded exercise test on a cycle ergometer before and after completion of the study. PBMC from compliant subjects (attended at least 70% of exercise sessions) were assessed for mitochondrial respiration using the Seahorse XF24 Bio-Analyzer. Seven of 24 enrolled subjects were compliant with the exercise regimen. In these individuals, a significant increase (p = .04) in VO 2MAX over 12 weeks was found with a median increase of 14%. During the same interval, a 2.45-fold increase in PBMC mitochondrial respiratory capacity (p = .04), a 5.65-fold increase in spare respiratory capacity (p = .01), and a 3.15-fold (p = .04) increase in nonmitochondrial respiration was observed. Aerobic exercise improves respiration at the cellular level. The diagnostic and prognostic value of such improved cellular respiration in the setting of chronic HIV warrants further investigation.

Effects of curative treatment emphasizing endurance training on the performance and blood pressure of hypertensive and normotensives

NASA Technical Reports Server (NTRS)

Worms, F.

1981-01-01

The problem of normal values of blood pressure after exercise taking into account the blood pressure at the end of the exercise test is discussed. Hypertensives showed a lower working capacity than normotensives. In normotensives, however, systolic blood pressure at the end of an exercise correlated well with the working capacity. After the endurance cure submaximal blood pressure was markedly lower in hypertensives with a striking dependence on the level of initial values. Systolic blood pressure at the end of an exercise test was not changed significantly. Most probably it is not possible to overcome this malregulation in hypertensives by endurance training alone.

Cardiopulmonary response during whole-body vibration training in patients with severe COPD

PubMed Central

Richter, Petra; Winterkamp, Sandra; Pfeifer, Michael; Nell, Christoph; Christle, Jeffrey W.; Kenn, Klaus

2017-01-01

Several studies in patients with chronic obstructive pulmonary disease (COPD) have shown that whole-body vibration training (WBVT) has beneficial effects on exercise capacity. However, the acute cardiopulmonary demand during WBVT remains unknown and was therefore investigated in this study. Ten patients with severe COPD (forced expiratory volume in 1 s: 38±8% predicted) were examined on two consecutive days. On day one, symptom-limited cardiopulmonary exercise testing was performed on a cycle ergometer. The next day, six bouts of repeated squat exercises were performed in random order for one, two or three minutes either with or without WBVT while metabolic demands were simultaneously measured. Squat exercises with or without WBVT induced comparable ventilatory efficiency (minute ventilation (VE)/carbon dioxide production (V′CO2): 38.0±4.4 with WBVT versus 37.4±4.1 without, p=0.236). Oxygen uptake after 3 min of squat exercises increased from 339±40 mL·min−1 to 1060±160 mL·min−1 with WBVT and 988±124 mL min−1 without WBV (p=0.093). However, there were no significant differences between squat exercises with and without WBVT in oxygen saturation (90±4% versus 90±4%, p=0.068), heart rate (109±13 bpm versus 110±15 bpm, p=0.513) or dyspnoea (Borg scale 5±2 versus 5±2, p=0.279). Combining squat exercises with WBVT induced a similar cardiopulmonary response in patients with severe COPD compared to squat exercises without WBVT. Bearing in mind the small sample size, WBVT might be a feasible and safe exercise modality even in patients with severe COPD. PMID:28326310

Predictors of oxygen desaturation during submaximal exercise in 8,000 patients.

PubMed

Hadeli, K O; Siegel, E M; Sherrill, D L; Beck, K C; Enright, P L

2001-07-01

To determine predictors of oxygen desaturation during submaximal exercise in patients with various lung diseases. This retrospective case series used pulmonary function laboratory results from all patients referred to a major tertiary-care center. All patients > or = 35 years old who underwent spirometry, diffusing capacity of the lung for carbon monoxide (DLCO), lung volumes, and pulse oximetry during 3-min submaximal step-test exercise during 1996 were included (4,545 men and 3,472 women). Logistic regression models, correcting for gender, age, and weight, determined the odds ratios (ORs) for oxygen desaturation of > or = 4% during exercise for each category of lung function abnormality (compared to those with entirely normal lung function). Approximately 74% of the patients had airways obstruction, while only 5.6% had restriction of lung volumes. One third of those with obstruction had a low DLCO, compared to 56% with restriction, while 2.7% had a low DLCO without obstruction or restriction. The risk of oxygen desaturation during submaximal exercise was very high (OR, 34) in patients with restriction and low DLCO (as in interstitial lung disease) and in patients with obstruction and low DLCO (as in COPD; OR, 18), intermediate (OR, 9) in patients with only a low DLCO, and lowest in those with a normal DLCO (OR, 4 if restricted; OR, 2 if obstructed). A cut point of DLCO < 62% predicted resulted in 75% sensitivity and specificity for exercise desaturation. No untoward cardiac events occurred in any patients during or following the submaximal exercise tests. The risk of oxygen desaturation during submaximal exercise is very high in patients with a low DLCO. Submaximal exercise tests are safe, even in elderly patients with heart and lung diseases.

Exercise-mediated vasodilation in human obesity and metabolic syndrome: effect of acute ascorbic acid infusion.

PubMed

Limberg, Jacqueline K; Kellawan, J Mikhail; Harrell, John W; Johansson, Rebecca E; Eldridge, Marlowe W; Proctor, Lester T; Sebranek, Joshua J; Schrage, William G

2014-09-15

We tested the hypothesis that infusion of ascorbic acid (AA), a potent antioxidant, would alter vasodilator responses to exercise in human obesity and metabolic syndrome (MetSyn). Forearm blood flow (FBF, Doppler ultrasound) was measured in lean, obese, and MetSyn adults (n = 39, 32 ± 2 yr). A brachial artery catheter was inserted for blood pressure monitoring and local infusion of AA. FBF was measured during dynamic handgrip exercise (15% maximal effort) with and without AA infusion. To account for group differences in blood pressure and forearm size, and to assess vasodilation, forearm vascular conductance (FVC = FBF/mean arterial blood pressure/lean forearm mass) was calculated. We examined the time to achieve steady-state FVC (mean response time, MRT) and the rise in FVC from rest to steady-state exercise (Δ, exercise - rest) before and during acute AA infusion. The MRT (P = 0.26) and steady-state vasodilator responses to exercise (ΔFVC, P = 0.31) were not different between groups. Intra-arterial infusion of AA resulted in a significant increase in plasma total antioxidant capacity (174 ± 37%). AA infusion did not alter MRT or steady-state FVC in any group (P = 0.90 and P = 0.85, respectively). Interestingly, higher levels of C-reactive protein predicted longer MRT (r = 0.52, P < 0.01) and a greater reduction in MRT with AA infusion (r = -0.43, P = 0.02). We concluded that AA infusion during moderate-intensity, rhythmic forearm exercise does not alter the time course or magnitude of exercise-mediated vasodilation in groups of young lean, obese, or MetSyn adults. However, systemic inflammation may limit the MRT to exercise, which can be improved with AA. Copyright © 2014 the American Physiological Society.

Exercise-mediated vasodilation in human obesity and metabolic syndrome: effect of acute ascorbic acid infusion

PubMed Central

Limberg, Jacqueline K.; Kellawan, J. Mikhail; Harrell, John W.; Johansson, Rebecca E.; Eldridge, Marlowe W.; Proctor, Lester T.; Sebranek, Joshua J.

2014-01-01

We tested the hypothesis that infusion of ascorbic acid (AA), a potent antioxidant, would alter vasodilator responses to exercise in human obesity and metabolic syndrome (MetSyn). Forearm blood flow (FBF, Doppler ultrasound) was measured in lean, obese, and MetSyn adults (n = 39, 32 ± 2 yr). A brachial artery catheter was inserted for blood pressure monitoring and local infusion of AA. FBF was measured during dynamic handgrip exercise (15% maximal effort) with and without AA infusion. To account for group differences in blood pressure and forearm size, and to assess vasodilation, forearm vascular conductance (FVC = FBF/mean arterial blood pressure/lean forearm mass) was calculated. We examined the time to achieve steady-state FVC (mean response time, MRT) and the rise in FVC from rest to steady-state exercise (Δ, exercise − rest) before and during acute AA infusion. The MRT (P = 0.26) and steady-state vasodilator responses to exercise (ΔFVC, P = 0.31) were not different between groups. Intra-arterial infusion of AA resulted in a significant increase in plasma total antioxidant capacity (174 ± 37%). AA infusion did not alter MRT or steady-state FVC in any group (P = 0.90 and P = 0.85, respectively). Interestingly, higher levels of C-reactive protein predicted longer MRT (r = 0.52, P < 0.01) and a greater reduction in MRT with AA infusion (r = −0.43, P = 0.02). We concluded that AA infusion during moderate-intensity, rhythmic forearm exercise does not alter the time course or magnitude of exercise-mediated vasodilation in groups of young lean, obese, or MetSyn adults. However, systemic inflammation may limit the MRT to exercise, which can be improved with AA. PMID:25038148

Voluntary exercise and its effects on body composition depend on genetic selection history.

PubMed

Nehrenberg, Derrick L; Hua, Kunjie; Estrada-Smith, Daria; Garland, Theodore; Pomp, Daniel

2009-07-01

Little is known about how genetic variation affects the capacity for exercise to change body composition. We examined the extent to which voluntary exercise alters body composition in several lines of selectively bred mice compared to controls. Lines studied included high runner (HR) (selected for high wheel running), M16 (selected for rapid weight gain), Institute of Cancer Research (ICR) (randomly bred as control for M16), M16i (an inbred line derived from M16), HE (selected for high percentage of body fat while holding body weight constant), LF (selected for low percentage of body fat), C57BL/6J (common inbred line), and the F1 between HR and C57BL/6J. Body weight and body fat were recorded before and after 6 days of free access to running wheels in males and females that were individually caged. Total food intake was measured during this 6-day period. All pre- and postexercise measures showed significant strain effects. While HR mice predictably exercised at higher levels, all other selection lines had decreased levels of wheel running relative to ICR. The HR x B6 F1 ran at similar levels to HR demonstrating complete dominance for voluntary exercise. Also, all strains lost body fat after exercise, but the relationships between exercise and changes in percent body were not uniform across genotypes. These results indicate that there is significant genetic variation for voluntary exercise and its effects on body composition. It is important to carefully consider genetic background and/or selection history when using mice to model effects of exercise on body composition, and perhaps, other complex traits as well.

Cardiopulmonary response during whole-body vibration training in patients with severe COPD.

PubMed

Gloeckl, Rainer; Richter, Petra; Winterkamp, Sandra; Pfeifer, Michael; Nell, Christoph; Christle, Jeffrey W; Kenn, Klaus

2017-01-01

Several studies in patients with chronic obstructive pulmonary disease (COPD) have shown that whole-body vibration training (WBVT) has beneficial effects on exercise capacity. However, the acute cardiopulmonary demand during WBVT remains unknown and was therefore investigated in this study. Ten patients with severe COPD (forced expiratory volume in 1 s: 38±8% predicted) were examined on two consecutive days. On day one, symptom-limited cardiopulmonary exercise testing was performed on a cycle ergometer. The next day, six bouts of repeated squat exercises were performed in random order for one, two or three minutes either with or without WBVT while metabolic demands were simultaneously measured. Squat exercises with or without WBVT induced comparable ventilatory efficiency (minute ventilation ( V E)/carbon dioxide production ( V' CO 2 ): 38.0±4.4 with WBVT versus 37.4±4.1 without, p=0.236). Oxygen uptake after 3 min of squat exercises increased from 339±40 mL·min -1 to 1060±160 mL·min -1 with WBVT and 988±124 mL min -1 without WBV (p=0.093). However, there were no significant differences between squat exercises with and without WBVT in oxygen saturation (90±4% versus 90±4%, p=0.068), heart rate (109±13 bpm versus 110±15 bpm, p=0.513) or dyspnoea (Borg scale 5±2 versus 5±2, p=0.279). Combining squat exercises with WBVT induced a similar cardiopulmonary response in patients with severe COPD compared to squat exercises without WBVT. Bearing in mind the small sample size, WBVT might be a feasible and safe exercise modality even in patients with severe COPD.

Active Video Game Exercise Training Improves the Clinical Control of Asthma in Children: Randomized Controlled Trial.

PubMed

Gomes, Evelim L F D; Carvalho, Celso R F; Peixoto-Souza, Fabiana Sobral; Teixeira-Carvalho, Etiene Farah; Mendonça, Juliana Fernandes Barreto; Stirbulov, Roberto; Sampaio, Luciana Maria Malosá; Costa, Dirceu

2015-01-01

The aim of the present study was to determine whether aerobic exercise involving an active video game system improved asthma control, airway inflammation and exercise capacity in children with moderate to severe asthma. A randomized, controlled, single-blinded clinical trial was carried out. Thirty-six children with moderate to severe asthma were randomly allocated to either a video game group (VGG; N = 20) or a treadmill group (TG; n = 16). Both groups completed an eight-week supervised program with two weekly 40-minute sessions. Pre-training and post-training evaluations involved the Asthma Control Questionnaire, exhaled nitric oxide levels (FeNO), maximum exercise testing (Bruce protocol) and lung function. No differences between the VGG and TG were found at the baseline. Improvements occurred in both groups with regard to asthma control and exercise capacity. Moreover, a significant reduction in FeNO was found in the VGG (p < 0.05). Although the mean energy expenditure at rest and during exercise training was similar for both groups, the maximum energy expenditure was higher in the VGG. The present findings strongly suggest that aerobic training promoted by an active video game had a positive impact on children with asthma in terms of clinical control, improvement in their exercise capacity and a reduction in pulmonary inflammation. Clinicaltrials.gov NCT01438294.

Active Video Game Exercise Training Improves the Clinical Control of Asthma in Children: Randomized Controlled Trial

PubMed Central

Gomes, Evelim L. F. D.; Carvalho, Celso R. F.; Peixoto-Souza, Fabiana Sobral; Teixeira-Carvalho, Etiene Farah; Mendonça, Juliana Fernandes Barreto; Stirbulov, Roberto; Sampaio, Luciana Maria Malosá; Costa, Dirceu

2015-01-01

Objective The aim of the present study was to determine whether aerobic exercise involving an active video game system improved asthma control, airway inflammation and exercise capacity in children with moderate to severe asthma. Design A randomized, controlled, single-blinded clinical trial was carried out. Thirty-six children with moderate to severe asthma were randomly allocated to either a video game group (VGG; N = 20) or a treadmill group (TG; n = 16). Both groups completed an eight-week supervised program with two weekly 40-minute sessions. Pre-training and post-training evaluations involved the Asthma Control Questionnaire, exhaled nitric oxide levels (FeNO), maximum exercise testing (Bruce protocol) and lung function. Results No differences between the VGG and TG were found at the baseline. Improvements occurred in both groups with regard to asthma control and exercise capacity. Moreover, a significant reduction in FeNO was found in the VGG (p < 0.05). Although the mean energy expenditure at rest and during exercise training was similar for both groups, the maximum energy expenditure was higher in the VGG. Conclusion The present findings strongly suggest that aerobic training promoted by an active video game had a positive impact on children with asthma in terms of clinical control, improvementin their exercise capacity and a reductionin pulmonary inflammation. Trial Registration Clinicaltrials.gov NCT01438294 PMID:26301706

Use of the Frank-Starling mechanism during exercise is linked to exercise-induced changes in arterial load

PubMed Central

Chantler, Paul D.; Melenovsky, Vojtech; Schulman, Steven P.; Gerstenblith, Gary; Becker, Lewis C.; Ferrucci, Luigi; Fleg, Jerome L.; Najjar, Samer S.

2012-01-01

Effective arterial elastance(EA) is a measure of the net arterial load imposed on the heart that integrates the effects of heart rate(HR), peripheral vascular resistance(PVR), and total arterial compliance(TAC) and is a modulator of cardiac performance. To what extent the change in EA during exercise impacts on cardiac performance and aerobic capacity is unknown. We examined EA and its relationship with cardiovascular performance in 352 healthy subjects. Subjects underwent rest and exercise gated scans to measure cardiac volumes and to derive EA[end-systolic pressure/stroke volume index(SV)], PVR[MAP/(SV*HR)], and TAC(SV/pulse pressure). EA varied with exercise intensity: the ΔEA between rest and peak exercise along with its determinants, differed among individuals and ranged from −44% to +149%, and was independent of age and sex. Individuals were separated into 3 groups based on their ΔEAI. Individuals with the largest increase in ΔEA(group 3;ΔEA≥0.98 mmHg.m2/ml) had the smallest reduction in PVR, the greatest reduction in TAC and a similar increase in HR vs. group 1(ΔEA<0.22 mmHg.m2/ml). Furthermore, group 3 had a reduction in end-diastolic volume, and a blunted increase in SV(80%), and cardiac output(27%), during exercise vs. group 1. Despite limitations in the Frank-Starling mechanism and cardiac function, peak aerobic capacity did not differ by group because arterial-venous oxygen difference was greater in group 3 vs. 1. Thus the change in arterial load during exercise has important effects on the Frank-Starling mechanism and cardiac performance but not on exercise capacity. These findings provide interesting insights into the dynamic cardiovascular alterations during exercise. PMID:22003052

Effect of antioxidant supplementation on exercise-induced cardiac troponin release in cyclists: a randomized trial.

PubMed

Klinkenberg, Lieke J J; Res, Peter T; Haenen, Guido R; Bast, Aalt; van Loon, Luc J C; van Dieijen-Visser, Marja P; Meex, Steven J R

2013-01-01

Cardiac troponin is the biochemical gold standard to diagnose acute myocardial infarction. Interestingly however, elevated cardiac troponin concentrations are also frequently observed during and after endurance-type exercise. Oxidative stress associated with prolonged exercise has been proposed to contribute to cardiac troponin release. Therefore, the aim of this study was to assess the effect of 4 week astaxanthin supplementation (a potent cartenoid antioxidant) on antioxidant capacity and exercise-induced cardiac troponin release in cyclists. Thirty-two well-trained male cyclists (age 25±5, weight 73±7 kg, maximum O2 uptake 60±5 mL·kg(-1)·min(-1), Wmax 5.4±0.5 W·kg(-1); mean ± SD) were repeatedly subjected to a laboratory based standardized exercise protocol before and after 4 weeks of astaxanthin (20 mg/day), or placebo supplementation in a double-blind randomized manner. Blood samples were obtained at baseline, at 60 min of cycling and immediately post-exercise (≈ 120 min). The pre-supplementation cycling trial induced a significant rise of median cardiac troponin T concentrations from 3.2 (IQR 3.0-4.2) to 4.7 ng/L (IQR 3.7-6.7), immediately post-exercise (p<0.001). Four weeks of astaxanthin supplementation significantly increased mean basal plasma astaxanthin concentrations from non-detectable values to 175±86 µg·kg(-1). However, daily astaxanthin supplementation had no effect on exercise-induced cardiac troponin T release (p = 0.24), as measured by the incremental area under the curve. Furthermore, the elevation in basal plasma astaxanthin concentrations was not reflected in changes in antioxidant capacity markers (trolox equivalent antioxidant capacity, uric acid, and malondialdehyde). Markers of inflammation (high-sensitivity C-reactive protein) and exercise-induced skeletal muscle damage (creatine kinase) were equally unaffected by astaxanthin supplementation. Despite substantial increases in plasma astaxanthin concentrations, astaxanthin supplementation did not improve antioxidant capacity in well-trained cyclists. Accordingly, exercise-induced cardiac troponin T concentrations were not affected by astaxanthin supplementation. ClinicalTrials.gov NCT01241877.

Effects of a Community-Based, Post-Rehabilitation Exercise Program in COPD: Protocol for a Randomized Controlled Trial With Embedded Process Evaluation.

PubMed

Desveaux, Laura; Beauchamp, Marla K; Lee, Annemarie; Ivers, Noah; Goldstein, Roger; Brooks, Dina

2016-05-11

This manuscript (1) outlines the intervention, (2) describes how its effectiveness is being evaluated in a pragmatic randomized controlled trial, and (3) summarizes the embedded process evaluation aiming to understand key barriers and facilitators for implementation in new environments. Participating centers refer eligible individuals with COPD following discharge from their local PR program. Consenting patients are assigned to a year-long community exercise program or usual care using block randomization and stratifying for supplemental oxygen use. Patients in the intervention arm are asked to attend an exercise session at least twice per week at their local community facility where their progress is supervised by a case manager. Each exercise session includes a component of aerobic exercise, and activities designed to optimize balance, flexibility, and strength. All study participants will have access to routine follow-up appointments with their respiratory physician, and additional health care providers as part of their usual care. Assessments will be completed at baseline (post-PR), 6, and 12 months, and include measures of functional exercise capacity, quality of life, self-efficacy, and health care usage. Intervention effectiveness will be assessed by comparing functional exercise capacity between intervention and control groups. A mixed-methods process evaluation will be conducted to better understand intervention implementation, guided by Normalization Process Theory and the Consolidated Framework for Implementation Research. Based on results from our pilot work, we anticipate a maintenance of exercise capacity and improved health-related quality of life in the intervention group, compared with a decline in exercise capacity in the usual care group. Findings from this study will improve our understanding of the effectiveness of community-based exercise programs for maintaining benefits following PR in patients with COPD and provide information on how best to implement them. If effective, the intervention represents an opportunity to transition patients from institutionally-based rehabilitative management to community-based care. The results of the process evaluation will contribute to the science of translating evidence-based programs into regular practice.

"EXHALE": exercise as a strategy for rehabilitation in advanced stage lung cancer patients: a randomized clinical trial comparing the effects of 12 weeks supervised exercise intervention versus usual care for advanced stage lung cancer patients.

PubMed

Quist, Morten; Langer, Seppo W; Rørth, Mikael; Christensen, Karl Bang; Adamsen, Lis

2013-10-14

Lung cancer is the leading cause of cancer death in North America and Western Europe. Patients with lung cancer in general have reduced physical capacity, functional capacity, poor quality of life and increased levels of anxiety and depression. Intervention studies indicate that physical training can address these issues. However, there is a lack of decisive evidence regarding the effect of physical exercise in patients with advanced lung cancer. The aim of this study is to evaluate the effects of a twelve weeks, twice weekly program consisting of: supervised, structured training in a group of advanced lung cancer patients (cardiovascular and strength training, relaxation). A randomized controlled trial will test the effects of the exercise intervention in 216 patients with advanced lung cancer (non-small cell lung cancer (NSCLC) stage IIIb-IV and small cell lung cancer (SCLC) extensive disease (ED)). Primary outcome is maximal oxygen uptake (VO₂peak). Secondary outcomes are muscle strength (1RM), functional capacity (6MWD), lung capacity (Fev1) and patient reported outcome (including anxiety, depression (HADS) and quality of life (HRQOL)). The present randomized controlled study will provide data on the effectiveness of a supervised exercise intervention in patients receiving systemic therapy for advanced lung cancer. It is hoped that the intervention can improve physical capacity and functional level, during rehabilitation of cancer patients with complex symptom burden and help them to maintain independent function for as long as possible. http://ClinicalTrials.gov, NCT01881906.

Is high-intensity interval training more effective on improving cardiometabolic risk and aerobic capacity than other forms of exercise in overweight and obese youth? A meta-analysis.

PubMed

García-Hermoso, A; Cerrillo-Urbina, A J; Herrera-Valenzuela, T; Cristi-Montero, C; Saavedra, J M; Martínez-Vizcaíno, V

2016-06-01

The scientific interest in high-intensity interval training (HIIT) has greatly increased during recent years. The objective of this meta-analysis was to determine the effectiveness of HIIT interventions on cardio-metabolic risk factors and aerobic capacity in overweight and obese youth, in comparison with other forms of exercise. A computerized search was made using seven databases. The analysis was restricted to studies that examined the effect of HIIT interventions on cardio-metabolic and/or aerobic capacity in pediatric obesity (6-17 years old). Nine studies using HIIT interventions were selected (n = 274). Standarized mean difference (SMD) and 95% confidence intervals were calculated. The DerSimonian-Laird approach was used. HIIT interventions (4-12 week duration) produced larger decreases in systolic blood pressure (SMD = 0.39; -3.63 mmHg) and greater increases in maximum oxygen uptake (SMD = 0.59; 1.92 ml/kg/min) than other forms of exercise. Also, type of comparison exercise group and duration of study were moderators. HIIT could be considered a more effective and time-efficient intervention for improving blood pressure and aerobic capacity levels in obese youth in comparison to other types of exercise. © 2016 World Obesity. © 2016 World Obesity.

Enhanced external counterpulsation - effect on angina pectoris, QoL and exercise capacity after 1 year.

PubMed

May, Ole; Lynggaard, Vibeke; Mortensen, Jesper C A; Malczynski, Jerzy

2015-02-01

Enhanced external counterpulsation (EECP) is a new therapy offered to patients with refractory angina pectoris (AP). To assess the effect of EECP on AP, quality of life (QoL) and exercise capacity in a design starting with a control period to avoid the influence of regression-towards-the-mean. Patients were examined two months before EECP, just before, just after, and three and 12 months after EECP. EECP was given for 1 h 5 days a week in 7 weeks. Three sets of pneumatic cuffs were mounted on the lower extremities and inflated sequentially in diastole to 260 mm Hg. 50 patients were included (male 72%, mean age: 62.5 years). Mean daily AP attacks were reduced during EECP from 2.7 to 0.9 (p < 0.005) and the Canadian Cardiovascular Society classification was reduced by at least 1 class in 82% just after EECP, 79% 3 months and 76% 12 months after EECP (p < 0.0002). Generic (SF36) and disease-specific QoL (Seattle AP questionnaire) improved just after, 3 and 12 months after compared with that before EECP. There was a significant improvement in exercise capacity and exercise-induced chest pain just after, three and 12 months after EECP (p < 0.02). No change was detected during the control period. EECP improves generic and disease-specific QoL, angina intensity and exercise capacity in at least 12 months.

33 CFR 155.5060 - Exercises.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Exercises. 155.5060 Section 155... § 155.5060 Exercises. (a) For nontank vessels with an oil capacity of 250 barrels or greater— (1) A... exercises as necessary to ensure that the VRP will function in an emergency. Vessel owners or operators must...

Exercise as a remedy for sarcopenia.

PubMed

Landi, Francesco; Marzetti, Emanuele; Martone, Anna M; Bernabei, Roberto; Onder, Graziano

2014-01-01

Although prolongation of life is a significant public health aim, at the same time the extended life should involve preservation of the capacity to live independently. Consequently, the identification of cost-effectiveness interventions to prevent frailty is one of the most important public health challenges. In the present review, we present the available evidence regarding the impact of physical exercise on the components of frailty syndrome and, in particular, as a remedy for sarcopenia. Resistance exercise training is more effective in increasing muscle mass and strength, whereas endurance exercises training is superior for maintaining and improving maximum aerobic power. Based on these evidences, recommendations for adult and frail older people should include a balanced program of both endurance and strength exercises, performed on a regular schedule (at least 3 days a week). Regular exercise is the only strategy found to consistently prevent frailty and improve sarcopenia and physical function in older adults. Physical exercises increase aerobic capacity, muscle strength and endurance, by ameliorating aerobic conditioning and/or strength. In older patients, exercise and physical activity produce at least the same beneficial effects observed in younger individuals.

Mitochondria-specific antioxidant supplementation does not influence endurance exercise training-induced adaptations in circulating angiogenic cells, skeletal muscle oxidative capacity or maximal oxygen uptake.

PubMed

Shill, Daniel D; Southern, W Michael; Willingham, T Bradley; Lansford, Kasey A; McCully, Kevin K; Jenkins, Nathan T

2016-12-01

Reducing excessive oxidative stress, through chronic exercise or antioxidants, can decrease the negative effects induced by excessive amounts of oxidative stress. Transient increases in oxidative stress produced during acute exercise facilitate beneficial vascular training adaptations, but the effects of non-specific antioxidants on exercise training-induced vascular adaptations remain elusive. Circulating angiogenic cells (CACs) are an exercise-inducible subset of white blood cells that maintain vascular integrity. We investigated whether mitochondria-specific antioxidant (MitoQ) supplementation would affect the response to 3 weeks of endurance exercise training in CACs, muscle mitochondrial capacity and maximal oxygen uptake in young healthy men. We show that endurance exercise training increases multiple CAC types, an adaptation that is not altered by MitoQ supplementation. Additionally, MitoQ does not affect skeletal muscle or whole-body aerobic adaptations to exercise training. These results indicate that MitoQ supplementation neither enhances nor attenuates endurance training adaptations in young healthy men. Antioxidants have been shown to improve endothelial function and cardiovascular outcomes. However, the effects of antioxidants on exercise training-induced vascular adaptations remain elusive. General acting antioxidants combined with exercise have not impacted circulating angiogenic cells (CACs). We investigated whether mitochondria-specific antioxidant (MitoQ) supplementation would affect the response to 3 weeks of endurance exercise training on CD3 + , CD3 + /CD31 + , CD14 + /CD31 + , CD31 + , CD34 + /VEGFR2 + and CD62E + peripheral blood mononuclear cells (PBMCs), muscle mitochondrial capacity, and maximal oxygen uptake (VO2 max ) in healthy men aged 22.1 ± 0.7 years, with a body mass index of 26.9 ± 0.9 kg m -2 , and 24.8 ± 1.3% body fat. Analysis of main effects revealed that training induced 33, 105 and 285% increases in CD14 + /CD31 + , CD62E + and CD34 + /VEGFR2 + CACs, respectively, and reduced CD3 + /CD31 - PBMCs by 14%. There was no effect of MitoQ on CAC levels. Also independent of MitoQ supplementation, exercise training significantly increased quadriceps muscle mitochondrial capacity by 24% and VO2 max by roughly 7%. In conclusion, endurance exercise training induced increases in multiple CAC types, and this adaptation is not modified by MitoQ supplementation. Furthermore, we demonstrate that a mitochondrial-targeted antioxidant does not influence skeletal muscle or whole-body aerobic adaptations to exercise training. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Prevalence and prediction of exercise-induced oxygen desaturation in patients with chronic obstructive pulmonary disease.

PubMed

van Gestel, A J R; Clarenbach, C F; Stöwhas, A C; Teschler, S; Russi, E W; Teschler, H; Kohler, M

2012-01-01

Previous studies with small sample sizes reported contradicting findings as to whether pulmonary function tests can predict exercise-induced oxygen desaturation (EID). To evaluate whether forced expiratory volume in one second (FEV(1)), resting oxygen saturation (SpO(2)) and diffusion capacity for carbon monoxide (DLCO) are predictors of EID in chronic obstructive pulmonary disease (COPD). We measured FEV(1), DLCO, SpO(2) at rest and during a 6-min walking test as well as physical activity by an accelerometer. A drop in SpO(2) of >4 to <90% was defined as EID. To evaluate associations between measures of lung function and EID univariate and multivariate analyses were used and positive/negative predictive values were calculated. Receiver operating characteristic curve analysis was performed to determine the most useful threshold in order to predict/exclude EID. We included 154 patients with COPD (87 females). The mean FEV(1) was 43.0% (19.2) predicted and the prevalence of EID was 61.7%. The only independent predictor of EID was FEV(1) and the optimal cutoff value of FEV(1) was at 50% predicted (area under ROC curve, 0.85; p < 0.001). The positive predictive value of a threshold of FEV(1) <50% was 0.83 with a likelihood ratio of 3.03 and the negative predicting value of a threshold of FEV(1) ≥80% was 1.0. The severity of EID was correlated with daily physical activity (r = -0.31, p = 0.008). EID is highly prevalent among patients with COPD and can be predicted by FEV(1). EID seems to be associated with impaired daily physical activity which supports its clinical importance. Copyright © 2012 S. Karger AG, Basel.

Asymptomatic peripheral artery disease can limit maximal exercise capacity in chronic obstructive pulmonary disease patients regardless of airflow obstruction and lung hyperinflation.

PubMed

Crisafulli, Ernesto; Scelfo, Chiara; Tzani, Panagiota; Aiello, Marina; Bertorelli, Giuseppina; Chetta, Alfredo

2017-06-01

Background Silent/asymptomatic peripheral artery disease may occur in patients with chronic obstructive pulmonary disease, but it is poorly investigated. The primary aim of this study was to evaluate in chronic obstructive pulmonary disease patients the impact of asymptomatic/silent peripheral artery disease on maximal exercise capacity; the secondary aim was to search for predictors of peripheral artery disease. Methods We prospectively enrolled chronic obstructive pulmonary disease outpatients. Data on anthropometric characteristics, lung function, cardiopulmonary exercise test and ankle-brachial index were recorded. The cut-off of ankle-brachial index used to define patients with peripheral artery disease was ≤0.90. Results We studied 47 patients and found 24 patients (51%) who showed peripheral artery disease. As compared to patients without peripheral artery disease, patients with peripheral artery disease had lower values of peak oxygen uptake, peak workload, energy expenditure (metabolic equivalents) and heart rate recovery, but showed the same degree of airflow obstruction and static and dynamic hyperinflation. In a multivariate linear regression model performed to identify variables predicting metabolic equivalents, ankle-brachial index (β 2.59; 95% confidence interval 0.51-4.67; p = 0.016) was an independent variable. In the search for predictors of peripheral artery disease, heart rate recovery (odds ratio 8.80; 95% confidence interval 1.30-59.35; p = 0.026) increased the risk of peripheral artery disease, whereas metabolic equivalents (odds ratio 0.50; 95% confidence interval 0.26-0.94, p = 0.033) and inhaled corticosteroids+long-acting β 2 agonists (odds ratio 0.13; 95% confidence interval 0.02-0.83; p = 0.030) reduced this risk. Conclusions In chronic obstructive pulmonary disease outpatients, asymptomatic/silent peripheral artery disease affects the maximal exercise capacity regardless of airflow obstruction and lung hyperinflation. A delay of heart rate recovery increase the risk of peripheral artery disease, whereas high values of metabolic equivalents and the use of inhaled corticosteroids+long-acting β 2 agonists reduces this risk.

Exercise training improves exercise capacity in adult patients with a systemic right ventricle: a randomized clinical trial.

PubMed

Winter, Michiel M; van der Bom, Teun; de Vries, Leonie C S; Balducci, Anna; Bouma, Berto J; Pieper, Petronella G; van Dijk, Arie P J; van der Plas, Mart N; Picchio, Fernando M; Mulder, Barbara J M

2012-06-01

To assess whether exercise training in adult patients with a systemic right ventricle (RV) improves exercise capacity and quality of life and lowers serum N-terminal prohormone brain natriuretic peptide (NT-proBNP) levels. Multi-centre parallel randomized controlled trial. Patients with a systemic RV due to congenitally or surgically corrected transposition of the great arteries. Fifty-four adult patients with a systemic RV, were randomized using unmarked opaque envelopes to an intervention group (n = 28) with three training sessions per week for 10 consecutive weeks, and a control group (n = 26). Randomization was stratified by participating centre. At baseline, and follow-up, we determined maximal exercise capacity (V'O(2peak)), serum NT-proBNP levels, and quality of life by means of the SF-36, and the TAAQOL Congenital Heart Disease questionnaires. The final analysis was performed by linear regression, taking into account the stratified randomization. Forty-six patients were analysed (male 50%, age 32 ± 11 years, intervention group n = 24, control group n = 22). Analysis at 10 weeks showed a significant difference in V'O(2peak) (3.4 mL/kg/min, 95% CI: 0.2 to 6.7; P = 0.04) and resting systolic blood pressure (-7.6 mmHg, 95% CI: -14.0 to -1.3; P = 0.03) in favour of the exercise group. No significant changes were found in serum NT-proBNP levels or quality of life in the intervention group or in the control group nor between groups. None of the patients in the intervention group had to discontinue the training programme due to adverse events. In adult patients with a systemic RV exercise training improve exercise capacity. We recommend to revise restrictive guidelines, and to encourage patients to become physically active. ( The study was registered at http://trialregister.nl. Identifier: NTR1909.).

Effects of an Exercise Programme on Functional Capacity, Body Composition and Risk of Falls in Patients with Cirrhosis: A Randomized Clinical Trial

PubMed Central

Román, Eva; García-Galcerán, Cristina; Torrades, Teresa; Herrera, Silvia; Marín, Ana; Doñate, Maite; Alvarado-Tapias, Edilmar; Malouf, Jorge; Nácher, Laura; Serra-Grima, Ricard; Guarner, Carlos; Soriano, German

2016-01-01

Patients with cirrhosis often have functional limitations, decreased muscle mass, and a high risk of falls. These variables could improve with exercise. The aim was to study the effects of moderate exercise on functional capacity, body composition and risk of falls in patients with cirrhosis. Twenty-three cirrhotic patients were randomized to an exercise programme (n = 14) or to a relaxation programme (n = 9). Both programmes consisted of a one-hour session 3 days a week for 12 weeks. At the beginning and end of the study, we measured functional capacity using the cardiopulmonary exercise test, evaluated body composition using anthropometry and dual energy X-ray absorptiometry, and estimated risk of falls using the Timed Up&Go test. In the exercise group, cardiopulmonary exercise test showed an increase in total effort time (p<0.001) and ventilatory anaerobic threshold time (p = 0.009). Upper thigh circumference increased and mid-arm and mid-thigh skinfold thickness decreased. Dual energy X-ray absorptiometry showed a decrease in fat body mass (-0.94 kg, 95%CI -0.48 to -1.41, p = 0.003) and an increase in lean body mass (1.05 kg, 95%CI 0.27 to 1.82, p = 0.01), lean appendicular mass (0.38 kg, 95%CI 0.06 to 0.69, p = 0.03) and lean leg mass (0.34 kg, 95%CI 0.10 to 0.57, p = 0.02). The Timed Up&Go test decreased at the end of the study compared to baseline (p = 0.02). No changes were observed in the relaxation group. We conclude that a moderate exercise programme in patients with cirrhosis improves functional capacity, increases muscle mass, and decreases body fat and the Timed Up&Go time. Trial Registration: ClinicalTrials.gov NCT01447537 PMID:27011355

Inverse relationship between exercise economy and oxidative capacity in muscle.

PubMed

Hunter, Gary R; Bamman, Marcas M; Larson-Meyer, D Enette; Joanisse, Denis R; McCarthy, John P; Blaudeau, Tamilane E; Newcomer, Bradley R

2005-08-01

An inverse relationship has been shown between running and cycling exercise economy and maximum oxygen uptake (VO2max). The purposes were: 1) determine the relationship between walking economy and VO2max; and 2) determine the relationship between muscle metabolic economy and muscle oxidative capacity and fiber type. Subjects were 77 premenopausal normal weight women. Walking economy (1/VO2max) was measured at 3 mph and VO2max during graded treadmill test. Muscle oxidative phosphorylation rate (OxPhos), and muscle metabolic economy (force/ATP) were measured in calf muscle using 31P MRS during isometric plantar flexion at 70 and 100% of maximum force, (HI) and (MI) respectively. Muscle fiber type and citrate synthase activity were determined in the lateral gastrocnemius. Significant inverse relationships (r from -0.28 to -0.74) were observed between oxidative metabolism measures and exercise economy (walking and muscle). Type IIa fiber distribution was inversely related to all measures of exercise economy (r from -0.51 to -0.64) and citrate synthase activity was inversely related to muscle metabolic economy at MI (r = -0.56). In addition, Type IIa fiber distribution and citrate synthase activity were positively related to VO2max and muscle OxPhos at HI and MI (r from 0.49 to 0.70). Type I fiber distribution was not related to any measure of exercise economy or oxidative capacity. Our results support the concept that exercise economy and oxidative capacity are inversely related. We have demonstrated this inverse relationship in women both by indirect calorimetry during walking and in muscle tissue by 31P MRS.

An overview of the issues: physiological effects of bed rest and restricted physical activity

NASA Technical Reports Server (NTRS)

Convertino, V. A.; Bloomfield, S. A.; Greenleaf, J. E.

1997-01-01

Reduction of exercise capacity with confinement to bed rest is well recognized. Underlying physiological mechanisms include dramatic reductions in maximal stroke volume, cardiac output, and oxygen uptake. However, bed rest by itself does not appear to contribute to cardiac dysfunction. Increased muscle fatigue is associated with reduced muscle blood flow, red cell volume, capillarization and oxidative enzymes. Loss of muscle mass and bone density may be reflected by reduced muscle strength and higher risk for injury to bones and joints. The resultant deconditioning caused by bed rest can be independent of the primary disease and physically debilitating in patients who attempt to reambulate to normal active living and working. A challenge to clinicians and health care specialists has been the identification of appropriate and effective methods to restore physical capacity of patients during or after restricted physical activity associated with prolonged bed rest. The examination of physiological responses to bed rest deconditioning and exercise training in healthy subjects has provided significant information to develop effective rehabilitation treatments. The successful application of acute exercise to enhance orthostatic stability, daily endurance exercise to maintain aerobic capacity, or specific resistance exercises to maintain musculoskeletal integrity rather than the use of surgical, pharmacological, and other medical treatments for clinical conditions has been enhanced by investigation and understanding of underlying mechanisms that distinguish physical deconditioning from the disease. This symposium presents an overview of cardiovascular and musculoskeletal deconditioning associated with reduced physical work capacity following prolonged bed rest and exercise training regimens that have proven successful in ameliorating or reversing these adverse effects.

Exercise Responses after Inactivity

NASA Technical Reports Server (NTRS)

Convertino, Victor A.

1986-01-01

The exercise response after bed rest inactivity is a reduction in the physical work capacity and is manifested by significant decreases in oxygen uptake. The magnitude of decrease in maximal oxygen intake V(dot)O2max is related to the duration of confinement and the pre-bed-rest level of aerobic fitness; these relationships are relatively independent of age and gender. The reduced exercise performance and V(dot)O2max following bed rest are associated with various physiological adaptations including reductions in blood volume, submaximal and maximal stroke volume, maximal cardiac output, sceletal muscle tone and strength, and aerobic enzyme capacities, as well as increases in venous compliance and submaximal and maximal heart rate. This reduction in physiological capacity can be partially restored by specific countermeasures that provide regular muscular activity or orhtostatic stress or both during the bed rest exposure. The understanding of these physiological and physical responses to exercise following bed rest inactivity has important implications for the solution to safety and health problems that arise in clinical medicine, aerospace medicine, sedentary living, and aging.

The role of exercise in modifying outcomes for people with multiple sclerosis: a randomized trial

PubMed Central

2013-01-01

Background Despite the commonly known benefits of exercise and physical activity evidence shows that persons Multiple Sclerosis (MS) are relatively inactive yet physical activity may be even more important in a population facing functional deterioration. No exercise is effective if it is not done and people with MS face unique barriers to exercise engagement which need to be overcome. We have developed and pilot tested a Multiple Sclerosis Tailored Exercise Program (MSTEP) and it is ready to be tested against general guidelines for superiority and ultimately for its impact on MS relevant outcomes. The primary research question is to what extent does an MS Tailored Exercise Program (MSTEP) result in greater improvements in exercise capacity and related outcomes over a one year period in comparison to a program based on general guidelines for exercise among people with MS who are sedentary and wish to engage in exercise as part of MS self-management. Methods/Design The proposed study is an assessor-blind, parallel-group, randomized controlled trial (RCT). The duration of the intervention will be one year with follow-up to year two. The targeted outcomes are exercise capacity, functional ambulation, strength, and components of quality of life including frequency and intensity of fatigue symptoms, mood, global physical function, health perception, and objective measures of activity level. Logistic regression will be used to test the main hypothesis related to the superiority of the MSTEP program based on a greater proportion of people making a clinically relevant gain in exercise capacity at 1 year and at 2 years, using an intention-to-treat approach. Sample size will be 240 (120 per group). Discussion The MS community is clearly looking for interventions to help alleviate the disabling sequelae of MS and promote health. Exercise is a well-known intervention which has known benefits to all, yet few exercise regularly. For people with MS, the role of exercise in MS management needs to be rigorously assessed to inform people as to how best to use exercise to reduce disability and promote health. Trial registration Clinical Trials.gov: NCT01611987 PMID:23809312

Lung function parameters improve prediction of VO2peak in an elderly population: The Generation 100 study.

PubMed

Hassel, Erlend; Stensvold, Dorthe; Halvorsen, Thomas; Wisløff, Ulrik; Langhammer, Arnulf; Steinshamn, Sigurd

2017-01-01

Peak oxygen uptake (VO2peak) is an indicator of cardiovascular health and a useful tool for risk stratification. Direct measurement of VO2peak is resource-demanding and may be contraindicated. There exist several non-exercise models to estimate VO2peak that utilize easily obtainable health parameters, but none of them includes lung function measures or hemoglobin concentrations. We aimed to test whether addition of these parameters could improve prediction of VO2peak compared to an established model that includes age, waist circumference, self-reported physical activity and resting heart rate. We included 1431 subjects aged 69-77 years that completed a laboratory test of VO2peak, spirometry, and a gas diffusion test. Prediction models for VO2peak were developed with multiple linear regression, and goodness of fit was evaluated. Forced expiratory volume in one second (FEV1), diffusing capacity of the lung for carbon monoxide and blood hemoglobin concentration significantly improved the ability of the established model to predict VO2peak. The explained variance of the model increased from 31% to 48% for men and from 32% to 38% for women (p<0.001). FEV1, diffusing capacity of the lungs for carbon monoxide and hemoglobin concentration substantially improved the accuracy of VO2peak prediction when added to an established model in an elderly population.

A transcriptional signature of "exercise resistance" in skeletal muscle of individuals with type 2 diabetes mellitus.

PubMed

Stephens, Natalie A; Xie, Hui; Johannsen, Neil M; Church, Timothy S; Smith, Steven R; Sparks, Lauren M

2015-09-01

Exercise benefits most, but not all, individuals with type 2 diabetes mellitus (T2DM). The aim of this study was to determine whether a proportion of individuals with T2DM would fail to demonstrate exercise-induced metabolic improvements. We hypothesized that this lack of response would be related to their skeletal muscle transcriptional profile. 42 participants with T2DM from the previously reported HART-D study underwent a 9-month supervised exercise intervention. We performed a principal components analysis to distinguish Responders from Non-Responders (n=9 each) based on: decreases in (1) HbA1c, (2) %fat (3) BMI and (4) increase in skeletal muscle mtDNA. mRNA expression patterns in muscle tissue at baseline were assessed by microarray and qRT-PCR analysis in both groups. Of 186 genes identified by microarray analysis, 70% were up-regulated in Responders and down-regulated in Non-Responders. Several genes involved in substrate metabolism and mitochondrial biogenesis were significantly different (fold-change>1.5, p<0.05) between the groups at baseline, indicating a blunted oxidative capacity at baseline in Non-Responders. These data suggest that a unique baseline expression pattern of genes involved in muscle fuel metabolism may predict an individual's lack of exercise response in metabolic outcomes, thus allowing exercise interventions to be targeted to these individuals and aid in the identification of novel approaches to treat Non-Responders in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

Training enhances attentional expertise, but not attentional capacity: Evidence from content-specific training benefits.

PubMed

Strong, Roger W; Alvarez, George A

2017-04-01

Cognitive training has become a billion-dollar industry with the promise that exercising a cognitive faculty (e.g., attention) on simple "brain games" will lead to improvements on any task relying on the same faculty. Although this logic seems sound, it assumes performance improves on training tasks because attention's capacity has been enhanced. Alternatively, training may result in attentional expertise-an enhancement of the ability to deploy attention to particular content-such that improvement on training tasks is specific to the features of the training context. The present study supported this attentional expertise hypothesis, showing that training benefits did not generalize fully from a trained attentional tracking task to untrained tracking tasks requiring a common attentional capacity, but differing in seemingly superficial features (i.e., retinotopic location and or motion type). This specificity suggests that attentional training benefits are linked to enhanced coordination between attentional processes and content-specific perceptual representations. Thus, these results indicate that shared attentional capacity between tasks is insufficient for producing generalized training benefits, and predict that generalization requires attentional expertise for content present in both training and outcome tasks.

Cardiopulmonary functional capacity and the role of exercise in improving maximal oxygen consumption in women with PCOS.

PubMed

Lenarcik, Agnieszka; Bidzińska-Speichert, Bozena

2010-01-01

Polycystic ovary syndrome (PCOS) is one of the most common reproductive disorder in premenopausal women and is frequently accompanied by the presence of cardiovascular risk factors. It has also been recognized that PCOS women are characterized by cardiopulmonary impairment. Reduced cardiopulmonary functional capacity and the autonomic dysfunction associated with abnormal heart rate recovery might be responsible for the increased cardiovascular risk in patients with PCOS. Exercise training has beneficial effects on cardiopulmonary functional capacity and reduces the risk of cardiovascular disease in PCOS women.

Exercise Training and Peripheral Arterial Disease

PubMed Central

Haas, Tara L.; Lloyd, Pamela G.; Yang, Hsiao-Tung; Terjung, Ronald L.

2013-01-01

Peripheral arterial disease (PAD) is a common vascular disease that reduces blood flow capacity to the legs of patients. PAD leads to exercise intolerance that can progress in severity to greatly limit mobility, and in advanced cases leads to frank ischemia with pain at rest. It is estimated that 12–15 million people in the United States are diagnosed with PAD, with a much larger population that is undiagnosed. The presence of PAD predicts a 50–1500% increase in morbidity and mortality, depending on severity. Treatment of patients with PAD is limited to modification of cardiovascular disease risk factors, pharmacological intervention, surgery, and exercise therapy. Extended exercise programs that involve walking ~5 times/wk, at a significant intensity that requires frequent rest periods, are most significant. Pre-clinical studies and virtually all clinical trials demonstrate the benefits of exercise therapy, including: improved walking tolerance, modified inflammatory/hemostatic markers, enhanced vasoresponsiveness, adaptations within the limb (angiogenesis, arteriogenesis, mitochondrial synthesis) that enhance oxygen delivery and metabolic responses, potentially delayed progression of the disease, enhanced quality of life indices, and extended longevity. A synthesis is provided as to how these adaptations can develop in the context of our current state of knowledge and events known to be orchestrated by exercise. The benefits are so compelling that exercise prescription should be an essential option presented to patients with PAD in the absence of contraindications. Obviously, selecting for a life style pattern, that includes enhanced physical activity prior to the advance of PAD limitations, is the most desirable and beneficial. PMID:23720270

Exercise rescues obese mothers' insulin sensitivity, placental hypoxia and male offspring insulin sensitivity.

PubMed

Fernandez-Twinn, Denise S; Gascoin, Geraldine; Musial, Barbara; Carr, Sarah; Duque-Guimaraes, Daniella; Blackmore, Heather L; Alfaradhi, Maria Z; Loche, Elena; Sferruzzi-Perri, Amanda N; Fowden, Abigail L; Ozanne, Susan E

2017-03-14

The prevalence of obesity during pregnancy continues to increase at alarming rates. This is concerning as in addition to immediate impacts on maternal wellbeing, obesity during pregnancy has detrimental effects on the long-term health of the offspring through non-genetic mechanisms. A major knowledge gap limiting our capacity to develop intervention strategies is the lack of understanding of the factors in the obese mother that mediate these epigenetic effects on the offspring. We used a mouse model of maternal-diet induced obesity to define predictive correlations between maternal factors and offspring insulin resistance. Maternal hyperinsulinemia (independent of maternal body weight and composition) strongly associated with offspring insulin resistance. To test causality, we implemented an exercise intervention that improved maternal insulin sensitivity without changing maternal body weight or composition. This maternal intervention prevented excess placental lipid deposition and hypoxia (independent of sex) and insulin resistance in male offspring. We conclude that hyperinsulinemia is a key programming factor and therefore an important interventional target during obese pregnancy, and propose moderate exercise as a promising strategy to improve metabolic outcome in both the obese mother and her offspring.

Dialysis exercise team: the way to sustain exercise programs in hemodialysis patients.

PubMed

Capitanini, Alessandro; Lange, Sara; D'Alessandro, Claudia; Salotti, Emilio; Tavolaro, Alba; Baronti, Maria E; Giannese, Domenico; Cupisti, Adamasco

2014-01-01

Patients affected by end-stage renal disease (ESRD) show quite lower physical activity and exercise capacity when compared to healthy individuals. In addition, a sedentary lifestyle is favoured by lack of a specific counseling on exercise implementation in the nephrology care setting. Increasing physical activity level should represent a goal for every dialysis patient care management. Three crucial elements of clinical care may contribute to sustain a hemodialysis exercise program: a) involvement of exercise professionals, b) real commitment of nephrologists and dialysis professionals, c) individual patient adaptation of the exercise program. Dialysis staff have a crucial role to encourage and assist patients during intra-dialysis exercise, but other professionals should be included in the ideal "exercise team" for dialysis patients. Evaluation of general condition, comorbidities (especially cardiovascular), nutritional status and physical exercise capacity are mandatory to propose an exercise program, in either extra-dialysis or intra-dialysis setting. To this aim, nephrologist should lead a team of specialists and professionals including cardiologist, physiotherapist, exercise physiologist, renal dietician and nurse. In this scenario, dialysis nurses play a pivotal role since they guarantee a constant and direct approach. Unfortunately dialysis staff may often lack of information and formation about exercise management while they take care patients during the dialysis session. Building an effective exercise team, promoting the culture of exercise and increasing physical activity levels lead to a more complete and modern clinical care management of ESRD patients. © 2014 S. Karger AG, Basel.

Effects of exercise training on pulmonary hemodynamics, functional capacity and inflammation in pulmonary hypertension

PubMed Central

Richter, Manuel J.; Grimminger, Jan; Krüger, Britta; Ghofrani, Hossein A.; Mooren, Frank C.; Gall, Henning; Pilat, Christian; Krüger, Karsten

2017-01-01

Pulmonary hypertension (PH) is characterized by severe exercise limitation mainly attributed to the impairment of right ventricular function resulting from a concomitant elevation of pulmonary vascular resistance and pressure. The unquestioned cornerstone in the management of patients with pulmonary arterial hypertension (PAH) is specific vasoactive medical therapy to improve pulmonary hemodynamics and strengthen right ventricular function. Nevertheless, evidence for a beneficial effect of exercise training (ET) on pulmonary hemodynamics and functional capacity in patients with PH has been growing during the past decade. Beneficial effects of ET on regulating factors, inflammation, and metabolism have also been described. Small case-control studies and randomized clinical trials in larger populations of patients with PH demonstrated substantial improvements in functional capacity after ET. These findings were accompanied by several studies that suggested an effect of ET on inflammation, although a direct link between this effect and the therapeutic benefit of ET in PH has not yet been demonstrated. On this background, the aim of the present review is to describe current concepts regarding the effects of exercise on the pulmonary circulation and pathophysiological limitations, as well as the clinical and mechanistic effects of exercise in patients with PH. PMID:28680563

Allopurinol reduces B-type natriuretic peptide concentrations and haemoglobin but does not alter exercise capacity in chronic heart failure.

PubMed

Gavin, A D; Struthers, A D

2005-06-01

To study whether the effect of allopurinol on improvement of endothelial dysfunction in chronic heart failure (CHF) translates into improved exercise capacity and to examine whether allopurinol also improves B-type natriuretic peptide (BNP), the other important prognostic marker of CHF. Randomised, double blind, placebo controlled crossover trial. Teaching hospital. 50 patients with CHF (New York Heart Association functional classes II and III) were recruited. 50 patients with CHF were randomly assigned to three months' treatment with allopurinol (300 mg/day) or placebo. At two and three months into treatment, they underwent a modified Bruce exercise protocol and a six minute walk test. Blood was taken for BNP and haemoglobin analysis. Neither exercise test was altered by allopurinol. However, plasma BNP concentrations fell significantly (p = 0.035) with allopurinol (11.9 pmol/l) versus placebo (14.4 pmol/l). Haemoglobin concentrations also fell highly significantly with allopurinol (p = 0.001). An important negative finding is that despite high hopes for it, allopurinol had no effect on exercise capacity in CHF. On the other hand, allopurinol did reduce BNP, which is the best available surrogate marker for prognosis in CHF.

Potential benefits of maximal exercise just prior to return from weightlessness

NASA Technical Reports Server (NTRS)

Convertino, Victor A.

1987-01-01

The purpose of this study was to determine whether performance of a single maximal bout of exercise during weightlessness within hours of return to earth would enhance recovery of aerobic fitness and physical work capacities under a 1G environment. Ten healthy men were subjected to a 10-d bedrest period in the 6-deg headdown position. A graded maximal supine cycle ergometer test was performed before and at the end of bedrest to simulate exercise during weightlessness. Following 3 h of resumption of the upright posture, a second maximal exercise test was performed on a treadmill to measure work capacity under conditions of 1G. Compared to before bedrest, peak oxygen consumption, V(O2), decreased by 8.7 percent and peak heart rate (HR) increased by 5.6 percent in the supine cycle test at the end of bedrest. However, there were no significant changes in peak V(O2) and peak HR in the upright treadmill test following bedrest. These data suggest that one bout of maximal leg exercise prior to return from 10 d of weightlessness may be adequate to restore preflight aerobic fitness and physical work capacity.

Supported treadmill ambulation for amyotrophic lateral sclerosis: a pilot study.

PubMed

Sanjak, Mohammed; Bravver, Elena; Bockenek, William L; Norton, H James; Brooks, Benjamin R

2010-12-01

To determine the feasibility, tolerability, safety, and exercise treatment-effect size of repetitive rhythmic exercise mediated by supported treadmill ambulation training (STAT) for patients with amyotrophic lateral sclerosis (ALS). Interventional with repeated-measures design. Multidisciplinary ALS clinic at academic medical center. Convenience sample of patients with ALS (N=9) who were ambulatory with assistive devices (Sinaki-Mulder stages II-III). Repetitive rhythmic exercise-STAT (30min total; 5min of exercise intercalated with 5min of rest) performed 3 times a week for 8 weeks. ALS Functional Rating Scale-Revised (ALSFRS-R), percentage of predicted vital capacity (VC), total lower-extremities manual muscle test (MMT), rate of perceived exertion (RPE), Fatigue Severity Scale (FSS), and maximum voluntary isometric contraction (MVIC) in 10 lower and 10 upper extremities. Gait performance, which included walking distance, speed, steps, and stride length, was evaluated during treadmill and ground 6-minute walk tests (6MWTs) and 25-foot walk test (25FWT). Feasibility issues decreased screened participants by 4 patients (31%). Nine patients were enrolled, but 6 patients (67%) completed the study and 3 (23% of original cohort; 33% of enrolled cohort) could not complete the exercise intervention because of non-ALS-related medical problems. Tolerability of the intervention measures during the treadmill 6MWT showed improvement in RPE (P≤.05) and FSS score (P≥.05). Safety measures (ALSFRS-R, VC, MMT) showed no decrease and showed statistical improvement in ALSFRS-R score (P≤.05) during the study interval. Exercise treatment-effect size showed variable improvements. Gait speed, distance, and stride length during the treadmill 6MWT improved significantly (P≤.05) after 4 weeks and improvements were maintained after 8 weeks compared with baseline. Walking distance during the ground 6MWT increased significantly after 4 weeks and was maintained after 8 weeks compared with baseline (P≤.05). Walking speed during the 25FWT and lower-extremity MVIC improved, but were not statistically significant. Repetitive rhythmic exercise-STAT is feasible, tolerated, and safe for patients with ALS. Repetitive rhythmic exercise-STAT treatment-effect size across a number of ALS-related measures was consistent with improved work capacity and gait function in patients with ALS who are dependent on assistive devices for ambulation. Repetitive rhythmic exercise-STAT should be evaluated further in larger studies to determine the stability of this improved function in relation to the rate of progression of the underlying ALS. Copyright © 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Mitochondria‐specific antioxidant supplementation does not influence endurance exercise training‐induced adaptations in circulating angiogenic cells, skeletal muscle oxidative capacity or maximal oxygen uptake

PubMed Central

Shill, Daniel D.; Southern, W. Michael; Willingham, T. Bradley; Lansford, Kasey A.; McCully, Kevin K.

2016-01-01

Key points Reducing excessive oxidative stress, through chronic exercise or antioxidants, can decrease the negative effects induced by excessive amounts of oxidative stress. Transient increases in oxidative stress produced during acute exercise facilitate beneficial vascular training adaptations, but the effects of non‐specific antioxidants on exercise training‐induced vascular adaptations remain elusive.Circulating angiogenic cells (CACs) are an exercise‐inducible subset of white blood cells that maintain vascular integrity.We investigated whether mitochondria‐specific antioxidant (MitoQ) supplementation would affect the response to 3 weeks of endurance exercise training in CACs, muscle mitochondrial capacity and maximal oxygen uptake in young healthy men.We show that endurance exercise training increases multiple CAC types, an adaptation that is not altered by MitoQ supplementation. Additionally, MitoQ does not affect skeletal muscle or whole‐body aerobic adaptations to exercise training.These results indicate that MitoQ supplementation neither enhances nor attenuates endurance training adaptations in young healthy men. Abstract Antioxidants have been shown to improve endothelial function and cardiovascular outcomes. However, the effects of antioxidants on exercise training‐induced vascular adaptations remain elusive. General acting antioxidants combined with exercise have not impacted circulating angiogenic cells (CACs). We investigated whether mitochondria‐specific antioxidant (MitoQ) supplementation would affect the response to 3 weeks of endurance exercise training on CD3+, CD3+/CD31+, CD14+/CD31+, CD31+, CD34+/VEGFR2+ and CD62E+ peripheral blood mononuclear cells (PBMCs), muscle mitochondrial capacity, and maximal oxygen uptake (VO2 max ) in healthy men aged 22.1 ± 0.7 years, with a body mass index of 26.9 ± 0.9 kg m–2, and 24.8 ± 1.3% body fat. Analysis of main effects revealed that training induced 33, 105 and 285% increases in CD14+/CD31+, CD62E+ and CD34+/VEGFR2+ CACs, respectively, and reduced CD3+/CD31− PBMCs by 14%. There was no effect of MitoQ on CAC levels. Also independent of MitoQ supplementation, exercise training significantly increased quadriceps muscle mitochondrial capacity by 24% and VO2 max by roughly 7%. In conclusion, endurance exercise training induced increases in multiple CAC types, and this adaptation is not modified by MitoQ supplementation. Furthermore, we demonstrate that a mitochondrial‐targeted antioxidant does not influence skeletal muscle or whole‐body aerobic adaptations to exercise training. PMID:27501153

Exercise therapy for an older patient with left ventricular assist device.

PubMed

Park, Won Hah; Seo, Yong Gon; Sung, Ji Dong

2014-06-01

A left ventricular assist device (LVAD) is a mechanical circulation support implanted for patients with end-stage heart failure. It may be used either as a bridge to cardiac transplantation or as a destination therapy. The health of a 75-year-old man with a medical history of systolic heart failure worsened. Therefore, he was recommended to have implanted a LVAD (Thoratec Corp.) as a destination therapy. After the surgery, he was enrolled in patient cardiac rehabilitation for the improvement of dyspnea and exercise capacity. In results, there is an improvement on his exercise capacity and quality of life. For the first time in Korea, we reported a benefit of exercise therapy after being implanted with a LVAD.

Baroreflex responses and LBNP tolerance following exercise training

NASA Technical Reports Server (NTRS)

Convertino, V. A.; Thompson, C. A.; Eckberg, D. L.; Fritsch, J. M.; Mack, G. W.; Nadel, E. R.

1990-01-01

The hypothesis that endurance exercise training designed to increase aerobic capacity results in reduced orthostatic tolerance due to alterations of blood-pressure controlling mechanisms was reexamined using a specially designed training in which tolerance to orthostasis and the primary mechanisms associated with the blood-pressure control could be measured before and after the increase in aerobic capacity. Results demonstrate that maximal oxygen uptake can be significantly elevated in individuals of average fit without reducing lower body negative pressure tolerance. The exercise training was found to cause a resting bradycardia, which had no effect on the cardiac vagal reflex response.

Exercise-based cardiac rehabilitation in heart transplant recipients.

PubMed

Anderson, Lindsey; Nguyen, Tricia T; Dall, Christian H; Burgess, Laura; Bridges, Charlene; Taylor, Rod S

2017-04-04

Heart transplantation is considered to be the gold standard treatment for selected patients with end-stage heart disease when medical therapy has been unable to halt progression of the underlying pathology. Evidence suggests that aerobic exercise training may be effective in reversing the pathophysiological consequences associated with cardiac denervation and prevent immunosuppression-induced adverse effects in heart transplant recipients. To determine the effectiveness and safety of exercise-based rehabilitation on the mortality, hospital admissions, adverse events, exercise capacity, health-related quality of life, return to work and costs for people after heart transplantation. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE (Ovid), Embase (Ovid), CINAHL (EBSCO) and Web of Science Core Collection (Thomson Reuters) to June 2016. We also searched two clinical trials registers and handsearched the reference lists of included studies. We included randomised controlled trials (RCTs) of parallel group, cross-over or cluster design, which compared exercise-based interventions with (i) no exercise control (ii) a different dose of exercise training (e.g. low- versus high-intensity exercise training); or (iii) an active intervention (i.e. education, psychological intervention). The study population comprised adults aged 18 years or over who had received a heart transplant. Two review authors independently screened all identified references for inclusion based on pre-specified inclusion criteria. Disagreements were resolved by consensus or by involving a third person. Two review authors extracted outcome data from the included trials and assessed their risk of bias. One review author extracted study characteristics from included studies and a second author checked them against the trial report for accuracy. We included 10 RCTs that involved a total of 300 participants whose mean age was 54.4 years. Women accounted for fewer than 25% of all study participants. Nine trials which randomised 284 participants to receive exercise-based rehabilitation (151 participants) or no exercise (133 participants) were included in the main analysis. One cross-over RCT compared high-intensity interval training with continued moderate-intensity training in 16 participants. We reported findings for all trials at their longest follow-up (median 12 weeks).Exercise-based cardiac rehabilitation increased exercise capacity (VO 2peak ) compared with no exercise control (MD 2.49 mL/kg/min, 95% CI 1.63 to 3.36; N = 284; studies = 9; moderate quality evidence). There was evidence from one trial that high-intensity interval exercise training was more effective in improving exercise capacity than continuous moderate-intensity exercise (MD 2.30 mL/kg/min, 95% CI 0.59 to 4.01; N = 16; 1 study). Four studies reported health-related quality of life (HRQoL) measured using SF-36, Profile of Quality of Life in the Chronically Ill (PLC) and the World Health Organization Quality Of Life (WHOQoL) - BREF. Due to the variation in HRQoL outcomes and methods of reporting we were unable to meta-analyse results across studies, but there was no evidence of a difference between exercise-based cardiac rehabilitation and control in 18 of 21 HRQoL domains reported, or between high and moderate intensity exercise in any of the 10 HRQoL domains reported. One adverse event was reported by one study.Exercise-based cardiac rehabilitation improves exercise capacity, but exercise was found to have no impact on health-related quality of life in the short-term (median 12 weeks follow-up), in heart transplant recipients whose health is stable.There was no evidence of statistical heterogeneity across trials for exercise capacity and no evidence of small study bias. The overall risk of bias in included studies was judged as low or unclear; more than 50% of included studies were assessed at unclear risk of bias with respect to allocation concealment, blinding of outcome assessors and declaration of conflicts of interest. Evidence quality was assessed as moderate according to GRADE criteria. We found moderate quality evidence suggesting that exercise-based cardiac rehabilitation improves exercise capacity, and that exercise has no impact on health-related quality of life in the short-term (median 12 weeks follow-up), in heart transplant recipients. Cardiac rehabilitation appears to be safe in this population, but long-term follow-up data are incomplete and further good quality and adequately-powered trials are needed to demonstrate the longer-term benefits of exercise on safety and impact on both clinical and patient-related outcomes, such as health-related quality of life, and healthcare costs.

Exercise training in older adults, what effects on muscle oxygenation? A systematic review.

PubMed

Fiogbé, Elie; de Vassimon-Barroso, Verena; de Medeiros Takahashi, Anielle Cristhine

2017-07-01

To determine the effects of different modality of exercise training programs on muscle oxygenation in older adults. Relevant articles were searched in PubMed, Web of Science, Science Direct and Scopus, using the keywords: "Aged" AND "Muscle oxygenation" AND (Exercise OR "Exercise therapy" OR "Exercise Movement Techniques" OR Hydrotherapy), without limitation concerning the publication date. To be included in the full analysis, the study had to be a randomized controlled trial in which older adults participants (mean age: 65 years at least) were submitted to an exercise-training program and muscle oxygenation assessment. The searches resulted in 1238 articles from which 7 met all the inclusion criteria. The trials involved 370 older adults (68.7±1.7years), healthy and with peripheral arterial disease. Studies included resistance and endurance exercises as well as walking sessions. Training sessions were 2-6 time per week, lasted 3-24 months and with different training intensity throughout studies. After a long-term resistance training, healthy older adults showed enhanced muscle oxygen extraction capacity, regulation of vessels and vascular endothelium function; endurance training is reported to improve microvascular blood flow and matching of oxygen delivery to oxygen utilization, muscle oxidative capacity and muscle saturation, and walking sessions results in better muscle oxygen availability and muscle oxygen extraction capacity in older adults with peripheral arterial disease. This review supports the fact that depending on the clinical status of the participants and the modality, exercise training improves different aspects of the muscle oxygenation in older adults. Copyright © 2017 Elsevier B.V. All rights reserved.

Exercise Training Reverses Extrapulmonary Impairments in Smoke-exposed Mice.

PubMed

Bowen, T Scott; Aakerøy, Lars; Eisenkolb, Sophia; Kunth, Patricia; Bakkerud, Fredrik; Wohlwend, Martin; Ormbostad, Anne Marie; Fischer, Tina; Wisloff, Ulrik; Schuler, Gerhard; Steinshamn, Sigurd; Adams, Volker; Bronstad, Eivind

2017-05-01

Cigarette smoking is the main risk factor for chronic obstructive pulmonary disease and emphysema. However, evidence on the extrapulmonary effects of smoke exposure that precede lung impairments remains unclear at present, as are data on nonpharmacological treatments such as exercise training. Three groups of mice, including control (n = 10), smoking (n = 10), and smoking with 6 wk of high-intensity interval treadmill running (n = 11), were exposed to 20 wk of fresh air or whole-body cigarette smoke. Exercise capacity (peak oxygen uptake) and lung destruction (histology) were subsequently measured, whereas the heart, peripheral endothelium (aorta), and respiratory (diaphragm) and limb (extensor digitorum longus and soleus) skeletal muscles were assessed for in vivo and in vitro function, in situ mitochondrial respiration, and molecular alterations. Smoking reduced body weight by 26% (P < 0.05) without overt airway destruction (P > 0.05). Smoking impaired exercise capacity by 15% while inducing right ventricular dysfunction by ~20%, endothelial dysfunction by ~20%, and diaphragm muscle weakness by ~15% (all P < 0.05), but these were either attenuated or reversed by exercise training (P < 0.05). Compared with controls, smoking mice had normal limb muscle and mitochondrial function (cardiac and skeletal muscle fibers); however, diaphragm measures of oxidative stress and protein degradation were increased by 111% and 65%, respectively (P < 0.05), but these were attenuated by exercise training (P < 0.05). Prolonged cigarette smoking reduced exercise capacity concomitant with functional impairments to the heart, peripheral endothelium, and respiratory muscle that preceded the development of overt emphysema. However, high-intensity exercise training was able to reverse these smoke-induced extrapulmonary impairments.

Neither Hematocrit Normalization nor Exercise Training Restores Oxygen Consumption to Normal Levels in Hemodialysis Patients

PubMed Central

Stray-Gundersen, James; Parsons, Dora Beth; Thompson, Jeffrey R.

2016-01-01

Patients treated with hemodialysis develop severely reduced functional capacity, which can be partially ameliorated by correcting anemia and through exercise training. In this study, we determined perturbations of an erythroid-stimulating agent and exercise training to examine if and where limitation to oxygen transport exists in patients on hemodialysis. Twenty-seven patients on hemodialysis completed a crossover study consisting of two exercise training phases at two hematocrit (Hct) values: 30% (anemic) and 42% (physiologic; normalized by treatment with erythroid-stimulating agent). To determine primary outcome measures of peak power and oxygen consumption (VO2) and secondary measures related to components of oxygen transport and utilization, all patients underwent numerous tests at five time points: baseline, untrained at Hct of 30%, after training at Hct of 30%, untrained at Hct of 42%, and after training at Hct of 42%. Hct normalization, exercise training, or the combination thereof significantly improved peak power and VO2 relative to values in the untrained anemic phase. Hct normalization increased peak arterial oxygen and arteriovenous oxygen difference, whereas exercise training improved cardiac output, citrate synthase activity, and peak tissue diffusing capacity. However, although the increase in arterial oxygen observed in the combination phase reached a value similar to that in healthy sedentary controls, the increase in peak arteriovenous oxygen difference did not. Muscle biopsy specimens showed markedly thickened endothelium and electron–dense interstitial deposits. In conclusion, exercise and Hct normalization had positive effects but failed to normalize exercise capacity in patients on hemodialysis. This effect may be caused by abnormalities identified within skeletal muscle. PMID:27153927

Iron Status in Chronic Heart Failure: Impact on Symptoms, Functional Class and Submaximal Exercise Capacity.

PubMed

Enjuanes, Cristina; Bruguera, Jordi; Grau, María; Cladellas, Mercé; Gonzalez, Gina; Meroño, Oona; Moliner-Borja, Pedro; Verdú, José M; Farré, Nuria; Comín-Colet, Josep

2016-03-01

To evaluate the effect of iron deficiency and anemia on submaximal exercise capacity in patients with chronic heart failure. We undertook a single-center cross-sectional study in a group of stable patients with chronic heart failure. At recruitment, patients provided baseline information and completed a 6-minute walk test to evaluate submaximal exercise capacity and exercise-induced symptoms. At the same time, blood samples were taken for serological evaluation. Iron deficiency was defined as ferritin < 100 ng/mL or transferrin saturation < 20% when ferritin is < 800 ng/mL. Additional markers of iron status were also measured. A total of 538 heart failure patients were eligible for inclusion, with an average age of 71 years and 33% were in New York Heart Association class III/IV. The mean distance walked in the test was 285 ± 101 meters among those with impaired iron status, vs 322 ± 113 meters (P=.002). Symptoms during the test were more frequent in iron deficiency patients (35% vs 27%; P=.028) and the most common symptom reported was fatigue. Multivariate logistic regression analyses showed that increased levels of soluble transferrin receptor indicating abnormal iron status were independently associated with advanced New York Heart Association class (P < .05). Multivariable analysis using generalized additive models, soluble transferrin receptor and ferritin index, both biomarkers measuring iron status, showed a significant, independent and linear association with submaximal exercise capacity (P=.03 for both). In contrast, hemoglobin levels were not significantly associated with 6-minute walk test distance in the multivariable analysis. In patients with chronic heart failure, iron deficiency but not anemia was associated with impaired submaximal exercise capacity and symptomatic functional limitation. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Determinants of expiratory flow limitation in healthy women during exercise.

PubMed

Dominelli, Paolo B; Guenette, Jordan A; Wilkie, Sabrina S; Foster, Glen E; Sheel, A William

2011-09-01

Expiratory flow limitation (EFL) can occur in healthy young women during exercise. We questioned whether the occurrence and severity of EFL were related to aerobic fitness or anatomical factors. Twenty-two healthy young (<40 yr) women performed a progressive cycle test to exhaustion. The subjects' maximum expiratory flow-volume curve was compiled from several effort-graded vital capacity maneuvers before and after exercise. The maximum expiratory flow-volume curve, along with inspiratory capacity maneuvers, was used to determine lung volumes and expiratory flows and to quantify EFL. To determine relative airway size, we used a ratio sensitive to both airway size and lung volume, called the dysanapsis ratio. The subjects were partitioned into two groups based upon the appearance of >5% EFL. Ten subjects showed EFL during exercise. Forced vital capacities (4.4 ± 0.4 vs 3.7 ± 0.4 L, P < 0.001) and forced expiratory flows for any given lung volume were significantly larger in the non-expiratory flow-limited (NEFL) group. The NEFL group's dysanapsis ratio was significantly larger than that of the EFL group (0.27 ± 0.06 vs 0.21 ± 0.04, respectively, P < 0.05), indicating larger airways in the NEFL group. There was no difference between the NEFL and EFL groups with respect to maximal aerobic capacity (50.8 ± 10.0 vs 46.7 ± 5.9 mL·kg(-1)·min(-1), respectively, P = 0.264). At peak exercise, the NEFL group had a significantly higher end-expiratory lung volume than the EFL group (40.1% ± 4.8% vs 33.7% ± 5.7% FVC, respectively, P < 0.05). We conclude that EFL in women can largely be explained by anatomical factors that influence the capacity to generate flow and volume during exercise rather than fitness per se.

Effects of heat acclimation on time perception.

PubMed

Tamm, Maria; Jakobson, Ainika; Havik, Merle; Timpmann, Saima; Burk, Andres; Ööpik, Vahur; Allik, Jüri; Kreegipuu, Kairi

2015-03-01

Cognitive performance is impaired during prolonged exercise in hot environment compared to temperate conditions. These effects are related to both peripheral markers of heats stress and alterations in CNS functioning. Repeated-exposure to heat stress results in physiological adaptations, and therefore improvement in exercise capacity and cognitive functioning are observed. The objective of the current study was to clarify the factors contributing to time perception under heat stress and examine the effect of heat acclimation. 20 young healthy male subjects completed three exercise tests on a treadmill: H1 (at 60% VO(2)peak until exhaustion at 42°C), N (at 22°C; duration equal to H1) and H2 (walk until exhaustion at 42°C) following a 10-day heat acclimation program. Core temperature (T(C)) and heart rate (HR), ratings of perceived fatigue and exertion were obtained continuously during the exercise, and blood samples of hormones were taken before, during and after the exercise test for estimating the prolactin, growth hormone and cortisol response to acute exercise-heat stress. Interval production task was performed before, during and after the exercise test. Lower rate of rise in core temperature, heart rate, hormone response and subjective ratings indicated that the subjects had successfully acclimated. Before heat acclimation, significant distortions in produced intervals occurred after 60 minutes of exercise relative to pre-trial coefficients, indicating speeded temporal processing. However, this effect was absent after in acclimated subjects. Blood prolactin concentration predicted temporal performance in both conditions. Heat acclimation slows down the increase in physiological measures, and improvement in temporal processing is also evident. The results are explained within the internal clock model in terms of the pacemaker-accumulator functioning. Copyright © 2014 Elsevier B.V. All rights reserved.

Exercise-Induced Dose-Response Alterations in Adiponectin and Leptin Levels Are Dependent on Body Fat Changes in Women at Risk for Breast Cancer.

PubMed

Sturgeon, Kathleen; Digiovanni, Laura; Good, Jerene; Salvatore, Domenick; Fenderson, Desiré; Domchek, Susan; Stopfer, Jill; Galantino, Mary Lou; Bryan, Cathy; Hwang, Wei-Ting; Schmitz, Kathryn

2016-08-01

Dysregulation of adipokines, such as adiponectin and leptin, is associated with a variety of chronic diseases, including cancer. Physical activity protects against breast cancer and one of the mechanisms which may underlie this association is exercise-induced changes in adipokine levels. The WISER Sister Trial was a three-armed randomized controlled trial in premenopausal women (n = 137) with an elevated risk for breast cancer. A 5-menstrual-cycle-long dosed aerobic exercise intervention compared low-dose exercise (150 min/wk; n = 44) or high-dose exercise (300 min/wk; n = 48) with a control group asked to maintain usual activity levels (n = 45). Exercise intensity progressed to and was maintained at 70% to 80% of age predicted heart rate max. Body composition and adipokine levels were measured at baseline and follow-up. We observed significant linear trends for increased fitness capacity (Δ%: -2.0% control, 10.1% low dose, 13.1% high dose), decreased fat tissue-to-total tissue mass (Δ%: 0.7% control, -2.9% low dose, -3.7% high dose), increased body fat adjusted adiponectin (Δ%: -0.6% control, 0.6% low dose, 0.9% high dose), and decreased body fat adjusted leptin (Δ%: 0.7% control, -8.2% low dose, -10.2% high dose). In this randomized clinical trial of premenopausal women at risk for breast cancer, we demonstrate a dose-response effect of exercise on adiponectin and leptin and that dose response is dependent on changes in body fat. Improved adipokine levels, achieved by aerobic exercise training-induced decreases in body fat, may decrease breast cancer risk for high-risk premenopausal women. Cancer Epidemiol Biomarkers Prev; 25(8); 1195-200. ©2016 AACR. ©2016 American Association for Cancer Research.

Assessment of Eccentric Exercise-Induced Oxidative Stress Using Oxidation-Reduction Potential Markers

PubMed Central

Stagos, Dimitrios; Goutzourelas, Nikolaos; Ntontou, Amalia-Maria; Kafantaris, Ioannis; Deli, Chariklia K.; Poulios, Athanasios; Jamurtas, Athanasios Z.; Bar-Or, David; Kouretas, Dimitrios

2015-01-01

The aim of the present study was to investigate the use of static (sORP) and capacity ORP (cORP) oxidation-reduction potential markers as measured by the RedoxSYS Diagnostic System in plasma, for assessing eccentric exercise-induced oxidative stress. Nineteen volunteers performed eccentric exercise with the knee extensors. Blood was collected before, immediately after exercise, and 24, 48, and 72 h after exercise. Moreover, common redox biomarkers were measured, which were protein carbonyls, thiobarbituric acid-reactive substances, total antioxidant capacity in plasma, and catalase activity and glutathione levels in erythrocytes. When the participants were examined as one group, there were not significant differences in any marker after exercise. However, in 11 participants there was a high increase in cORP after exercise, while in 8 participants there was a high decrease. Thus, the participants were divided in low cORP group exhibiting significant decrease in cORP after exercise and in high cORP group exhibiting significant increase. Moreover, only in the low cORP group there was a significant increase in lipid peroxidation after exercise suggesting induction of oxidative stress. The results suggested that high decreases in cORP values after exercise may indicate induction of oxidative stress by eccentric exercise, while high increases in cORP values after exercise may indicate no existence of oxidative stress. PMID:25874019

Effect of HX108-CS supplementation on exercise capacity and lactate accumulation after high-intensity exercise.

PubMed

Oh, Seung-Lyul; Chang, Hyukki; Kim, Hee-Jae; Kim, Yong-An; Kim, Dong-Sik; Ho, Seong-Hyun; Kim, Seon-Hee; Song, Wook

2013-04-15

In the present study, we determined the effects of HX108-CS (mixed extract of Schisandra chinensis and Chaenomeles sinensis) supplementation on lactate accumulation and endurance capacity. Furthermore, we examined CK (creatine kinase), LDH (lactate dehydrogenase) activity to determine whether the HX108-CS affected markers of skeletal muscle injury in vivo and in vitro. Exercise capacity was measured by an exhaustive swimming test using ICR mice divided into four groups; one group received distilled water (DW) (Control group, n = 10), and the other groups received three different dosages of HX108-CS (10, 50 and 100 mg/kg, n = 10 per group) solution in water orally. Then, for the time-dependent measurements of blood lactate, CK, and LDH, Sprague-Dawley rats were divided into two groups; one received DW (Control group, n = 10), and the other group received HX108-CS (100 mg/kg, n = 10) solution in the same way as mice. Before the exercise test, the animals were given either DW or HX108-CS for 2 weeks. High-intensity treadmill exercise was performed for 30 minutes. Blood samples were collected and analyzed during and after exercise. For the in vitro experiment, C2C12 cells were treated with HX108-CS to examine its effect on lactate production, CK, and LDH activity. Blood lactate concentration was significantly lowered immediately after treadmill exercise in HX108-CS group; however, there were no significant differences in activities of CK and LDH between HX108-CS and control during treadmill exercise and recovery phase. Furthermore, treatment with 100 mg/kg of HX108-CS led to a significant increase in the time to exhaustion in swimming test, and concurrently blood lactate concentration was significantly decreased in 50 and 100 mg/kg treated group. Moreover, our results of in vitro experiment showed that HX108-CS suppressed lactate production, CK, and LDH activity in a dose-dependent manner. These results suggest that supplementation with HX108-CS may enhance exercise capacity by lowering lactate accumulation. This may in part be related to an amelioration of skeletal muscle injury.

Increasing exercise capacity and quality of life of patients with heart failure through Wii gaming: the rationale, design and methodology of the HF-Wii study; a multicentre randomized controlled trial.

PubMed

Jaarsma, Tiny; Klompstra, Leonie; Ben Gal, Tuvia; Boyne, Josiane; Vellone, Ercole; Bäck, Maria; Dickstein, Kenneth; Fridlund, Bengt; Hoes, Arno; Piepoli, Massimo F; Chialà, Oronzo; Mårtensson, Jan; Strömberg, Anna

2015-07-01

Exercise is known to be beneficial for patients with heart failure (HF), and these patients should therefore be routinely advised to exercise and to be or to become physically active. Despite the beneficial effects of exercise such as improved functional capacity and favourable clinical outcomes, the level of daily physical activity in most patients with HF is low. Exergaming may be a promising new approach to increase the physical activity of patients with HF at home. The aim of this study is to determine the effectiveness of the structured introduction and access to a Wii game computer in patients with HF to improve exercise capacity and level of daily physical activity, to decrease healthcare resource use, and to improve self-care and health-related quality of life. A multicentre randomized controlled study with two treatment groups will include 600 patients with HF. In each centre, patients will be randomized to either motivational support only (control) or structured access to a Wii game computer (Wii). Patients in the control group will receive advice on physical activity and will be contacted by four telephone calls. Patients in the Wii group also will receive advice on physical activity along with a Wii game computer, with instructions and training. The primary endpoint will be exercise capacity at 3 months as measured by the 6 min walk test. Secondary endpoints include exercise capacity at 6 and 12 months, level of daily physical activity, muscle function, health-related quality of life, and hospitalization or death during the 12 months follow-up. The HF-Wii study is a randomized study that will evaluate the effect of exergaming in patients with HF. The findings can be useful to healthcare professionals and improve our understanding of the potential role of exergaming in the treatment and management of patients with HF. NCT01785121. © 2015 The Authors. European Journal of Heart Failure © 2015 European Society of Cardiology.

Nutrition for sports performance: issues and opportunities.

PubMed

Maughan, Ronald J; Shirreffs, Susan M

2012-02-01

Diet can significantly influence athletic performance, but recent research developments have substantially changed our understanding of sport and exercise nutrition. Athletes adopt various nutritional strategies in training and competition in the pursuit of success. The aim of training is to promote changes in the structure and function of muscle and other tissues by selective modulation of protein synthesis and breakdown in response to the training stimulus. This process is affected by the availability of essential amino acids in the post-exercise period. Athletes have been encouraged to eat diets high in carbohydrate, but low-carbohydrate diets up-regulate the capacity of muscle for fat oxidation, potentially sparing the limited carbohydrate stores. Such diets, however, do not enhance endurance performance. It is not yet known whether the increased capacity for fat oxidation that results from training in a carbohydrate-deficient state can promote loss of body fat. Preventing excessive fluid deficits will maintain exercise capacity, and ensuring adequate hydration status can also reduce subjective perception of effort. This latter effect may be important in encouraging exercise participation and promoting adherence to exercise programmes. Dietary supplement use is popular in sport, and a few supplements may improve performance in specific exercise tasks. Athletes must be cautious, however, not to contravene the doping regulations. There is an increasing recognition of the role of the brain in determining exercise performance: various nutritional strategies have been proposed, but with limited success. Nutrition strategies developed for use by athletes can also be used to achieve functional benefits in other populations.

Effects of inhaled ipratropium bromide on breathing mechanics and gas exchange in exercising horses with chronic obstructive pulmonary disease.

PubMed

Bayly, W M; Duvivier, D H; Votion, D; Vandenput, S; Art, T; Lekeux, P

2002-01-01

Six Warmblood horses suffering an acute exacerbation of COPD were tested to investigate whether inhalation of ipratropium bromide (IB) dry powder (2,400 microg) 30 min preexercise would improve their exercise capacity. A cross-over protocol with an inert powder placebo (P) was used. Mechanics of breathing and arterial blood gases were determined before treatment, after treatment but pre-exercise, and during an incremental exercise test. Oxygen consumption (VO2) was also measured before and during exercise, and the time to fatigue recorded. Inhalation of IB reduced total pulmonary resistance (RL) and maximum intrapleural pressure changes (deltaPpl(max)) and increased dynamic compliance before exercise. The onset of exercise was associated with a marked decrease in RL in P-treated horses but not those receiving IB, so that RL during exercise was not affected by treatment. Although deltaPpl(max) was lower at 8,9 and 10 m/s with IB, there were no treatment-related changes in VO2, blood gases, time to fatigue or any other measurement of breathing mechanics. Therefore, although inhalation of IB prior to exercise may have improved deltaPpl(max), it had no apparent impact on the horses' capacity for exercise.

Continuous low- to moderate-intensity exercise training is as effective as moderate- to high-intensity exercise training at lowering blood HbA(1c) in obese type 2 diabetes patients.

PubMed

Hansen, D; Dendale, P; Jonkers, R A M; Beelen, M; Manders, R J F; Corluy, L; Mullens, A; Berger, J; Meeusen, R; van Loon, L J C

2009-09-01

Exercise represents an effective interventional strategy to improve glycaemic control in type 2 diabetes patients. However, the impact of exercise intensity on the benefits of exercise training remains to be established. In the present study, we compared the clinical benefits of 6 months of continuous low- to moderate-intensity exercise training with those of continuous moderate- to high-intensity exercise training, matched for energy expenditure, in obese type 2 diabetes patients. Fifty male obese type 2 diabetes patients (age 59 +/- 8 years, BMI 32 +/- 4 kg/m(2)) participated in a 6 month continuous endurance-type exercise training programme. All participants performed three supervised exercise sessions per week, either 55 min at 50% of whole body peak oxygen uptake (VO(2)peak (low to moderate intensity) or 40 min at 75% of VO(2)peak (moderate to high intensity). Oral glucose tolerance, blood glycated haemoglobin, lipid profile, body composition, maximal workload capacity, whole body and skeletal muscle oxidative capacity and skeletal muscle fibre type composition were assessed before and after 2 and 6 months of intervention. The entire 6 month intervention programme was completed by 37 participants. Continuous endurance-type exercise training reduced blood glycated haemoglobin levels, LDL-cholesterol concentrations, body weight and leg fat mass, and increased VO(2)peak, lean muscle mass and skeletal muscle cytochrome c oxidase and citrate synthase activity (p < 0.05). No differences were observed between the groups training at low to moderate or moderate to high intensity. When matched for energy cost, prolonged continuous low- to moderate-intensity endurance-type exercise training is equally effective as continuous moderate- to high-intensity training in lowering blood glycated haemoglobin and increasing whole body and skeletal muscle oxidative capacity in obese type 2 diabetes patients. ISRCTN32206301 None.

Improved Arterial–Ventricular Coupling in Metabolic Syndrome after Exercise Training

PubMed Central

Fournier, Sara B.; Donley, David A.; Bonner, Daniel E.; DeVallance, Evan; Olfert, I. Mark; Chantler, Paul D.

2014-01-01

Purpose The metabolic syndrome (MetS) is associated with a three-fold increase risk of cardiovascular (CV) morbidity and mortality, which is in part, due to a blunted CV reserve capacity, reflected by a reduced peak exercise left ventricular contractility and aerobic capacity, and a blunted peak arterial-ventricular coupling. To date, no study has examined whether aerobic exercise training in MetS can reverse the peak exercise CV dysfunction. Further, examining how exercise training alters CV function in a group of individuals with MetS prior to the development of diabetes and/or overt CVD, can provide insights into whether some of the pathophysiological changes to the CV can be delayed/reversed, lowering their CV risk. The objective of this study was to examine the effects of 8 weeks of aerobic exercise training in individuals with MetS on resting and peak exercise CV function. Methods Twenty MetS underwent either 8 weeks of aerobic exercise training (MetS-ExT; n=10) or remained sedentary (MetS-NonT; n=10) during this time period. Resting and peak exercise CV function was characterized using Doppler echocardiography and gas exchange. Results Exercise training did not alter resting left ventricular diastolic or systolic function and arterial-ventricular coupling in MetS. In contrast, at peak exercise an increase in LV contractility (40%, p<0.01), cardiac output (28%, p<0.05) and aerobic capacity (20%, p<0.01), while a reduction in vascular resistance (30%, p<0.05) and arterial-ventricular coupling (27%, p<0.01), were noted in the MetS-ExT but not the MetS-NonT group. Further, an improvement in Lifetime Risk Score was also noted in the MetS-ExT group. Conclusions These findings have clinical importance as they provide insight that some of the pathophysiological changes associated with MetS can be improved and lower the risk of CVD. PMID:24870568

Improved arterial-ventricular coupling in metabolic syndrome after exercise training: a pilot study.

PubMed

Fournier, Sara B; Donley, David A; Bonner, Daniel E; Devallance, Evan; Olfert, I Mark; Chantler, Paul D

2015-01-01

The metabolic syndrome (MetS) is associated with threefold increased risk of cardiovascular (CV) morbidity and mortality, which is partly due to a blunted CV reserve capacity, reflected by a reduced peak exercise left ventricular (LV) contractility and aerobic capacity and a blunted peak arterial-ventricular coupling. To date, no study has examined whether aerobic exercise training in MetS can reverse peak exercise CV dysfunction. Furthermore, examining how exercise training alters CV function in a group of individuals with MetS before the development of diabetes and/or overt CV disease can provide insights into whether some of the pathophysiological CV changes can be delayed/reversed, lowering their CV risk. The objective of this study was to examine the effects of 8 wk of aerobic exercise training in individuals with MetS on resting and peak exercise CV function. Twenty participants with MetS underwent either 8 wk of aerobic exercise training (MetS-ExT, n = 10) or remained sedentary (MetS-NonT, n = 10) during this period. Resting and peak exercise CV function was characterized using Doppler echocardiography and gas exchange. Exercise training did not alter resting LV diastolic or systolic function and arterial-ventricular coupling in MetS. In contrast, at peak exercise, an increase in LV contractility (40%, P < 0.01), cardiac output (28%, P < 0.05), and aerobic capacity (20%, P < 0.01), but a reduction in vascular resistance (30%, P < 0.05) and arterial-ventricular coupling (27%, P < 0.01), were noted in the MetS-ExT but not in the MetS-NonT group. Furthermore, an improvement in lifetime risk score was also noted in the MetS-ExT group. These findings have clinical importance because they provide insight that some of the pathophysiological changes associated with MetS can be improved and can lower the risk of CV disease.

Separate and combined effects of exposure to heat stress and mental fatigue on endurance exercise capacity in the heat.

PubMed

Otani, Hidenori; Kaya, Mitsuharu; Tamaki, Akira; Watson, Phillip

2017-01-01

This study investigated the effects of exposure to pre-exercise heat stress and mental fatigue on endurance exercise capacity in a hot environment. Eight volunteers completed four cycle exercise trials at 80% maximum oxygen uptake until exhaustion in an environmental chamber maintained at 30 °C and 50% relative humidity. The four trials required them to complete a 90 min pre-exercise routine of either a seated rest (CON), a prolonged demanding cognitive task to induce mental fatigue (MF), warm water immersion at 40 °C during the last 30 min to induce increasing core temperature (WI), or a prolonged demanding cognitive task and warm water immersion at 40 °C during the last 30 min (MF + WI). Core temperature when starting exercise was higher following warm water immersion (~38 °C; WI and MF + WI) than with no water immersion (~36.8 °C; CON and MF, P < 0.001). Self-reported mental fatigue when commencing exercise was higher following cognitive task (MF and MF + WI) than with no cognitive task (CON and WI; P < 0.05). Exercise time to exhaustion was reduced by warm water immersion (P < 0.001) and cognitive task (P < 0.05). Compared with CON (18 ± 7 min), exercise duration reduced 0.8, 26.6 and 46.3% in MF (17 ± 7 min), WI (12 ± 5 min) and MF + WI (9 ± 3 min), respectively. This study demonstrates that endurance exercise capacity in a hot environment is impaired by either exposure to pre-exercise heat stress or mental fatigue, and this response is synergistically increased during combined exposure to them.

Engineering Improved Balance Confidence in Older Adults With Complex Health Care Needs: Learning From the Muscling Up Against Disability Study.

PubMed

Hetherington, Sharon; Henwood, Tim; Swinton, Paul; Keogh, Justin; Gardiner, Paul; Tuckett, Anthony; Rouse, Kevin

2018-04-05

To investigate the associations of balance confidence with physical and cognitive markers of well-being in older adults receiving government-funded aged care services and whether progressive resistance plus balance training could positively influence change. Intervention study. Community-based older adult-specific exercise clinic. Older adults (N=245) with complex care needs who were receiving government-funded aged care support. Twenty-four weeks of twice weekly progressive resistance plus balance training carried out under the supervision of accredited exercise physiologists. The primary measure was the Activity-specific Balance Confidence Scale. Secondary measures included the Short Physical Performance Battery; fall history gathered as part of the health history questionnaire; hierarchical timed balance tests; Geriatric Anxiety Index; Geriatric Depression Scale; Fatigue, Resistance, Ambulation, Illness, Loss of Weight scale; and EuroQoL-5 dimension 3 level. At baseline, better physical performance (r=.54; P<.01) and quality of life (r=.52; P<.01) predicted better balance confidence. In contrast, at baseline, higher levels of frailty predicted worse balance confidence (r=-.55; P<.01). Change in balance confidence after the exercise intervention was accompanied by improved physical performance (+12%) and reduced frailty (-11%). Baseline balance confidence was identified as the most consistent negative predictor of change scores across the intervention. This study shows that reduced physical performance and quality of life and increased frailty are predictive of worse balance confidence in older adults with aged care needs. However, when a targeted intervention of resistance and balance exercise is implemented that reduces frailty and improves physical performance, balance confidence will also improve. Given the influence of balance confidence on a raft of well-being determinants, including the capacity for positive physical and cognitive change, this study offers important insight to those looking to reduce falls in older adults. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Econometric estimation of country-specific hospital costs.

PubMed

Adam, Taghreed; Evans, David B; Murray, Christopher JL

2003-02-26

Information on the unit cost of inpatient and outpatient care is an essential element for costing, budgeting and economic-evaluation exercises. Many countries lack reliable estimates, however. WHO has recently undertaken an extensive effort to collect and collate data on the unit cost of hospitals and health centres from as many countries as possible; so far, data have been assembled from 49 countries, for various years during the period 1973-2000. The database covers a total of 2173 country-years of observations. Large gaps remain, however, particularly for developing countries. Although the long-term solution is that all countries perform their own costing studies, the question arises whether it is possible to predict unit costs for different countries in a standardized way for short-term use. The purpose of the work described in this paper, a modelling exercise, was to use the data collected across countries to predict unit costs in countries for which data are not yet available, with the appropriate uncertainty intervals.The model presented here forms part of a series of models used to estimate unit costs for the WHO-CHOICE project. The methods and the results of the model, however, may be used to predict a number of different types of country-specific unit costs, depending on the purpose of the exercise. They may be used, for instance, to estimate the costs per bed-day at different capacity levels; the "hotel" component of cost per bed-day; or unit costs net of particular components such as drugs.In addition to reporting estimates for selected countries, the paper shows that unit costs of hospitals vary within countries, sometimes by an order of magnitude. Basing cost-effectiveness studies or budgeting exercises on the results of a study of a single facility, or even a small group of facilities, is likely to be misleading.

Predicting short and long-term exercise intentions and behaviour in patients with coronary artery disease: A test of protection motivation theory.

PubMed

Tulloch, Heather; Reida, Robert; D'Angeloa, Monika Slovinec; Plotnikoff, Ronald C; Morrina, Louise; Beatona, Louise; Papadakisa, Sophia; Pipe, Andrew

2009-03-01

The purpose of this study was to examine the utility of protection motivation theory (PMT) in the prediction of exercise intentions and behaviour in the year following hospitalisation for coronary artery disease (CAD). Patients with documented CAD (n = 787), recruited at hospital discharge, completed questionnaires measuring PMT's threat (i.e. perceived severity and vulnerability) and coping (i.e. self-efficacy, response efficacy) appraisal constructs at baseline, 2 and 6 months, and exercise behaviour at baseline, 6 and 12 months post-hospitalisation. Structural equation modelling showed that the PMT model of exercise at 6 months had a good fit with the empirical data. Self-efficacy, response efficacy, and perceived severity predicted exercise intentions, which, in turn predicted exercise behaviour. Overall, the PMT variables accounted for a moderate amount of variance in exercise intentions (23%) and behaviour (20%). In contrast, the PMT model was not reliable for predicting exercise behaviour at 12 months post-hospitalisation. The data provided support for PMT applied to short-term, but not long-term, exercise behaviour among patients with CAD. Health education should concentrate on providing positive coping messages to enhance patients' confidence regarding exercise and their belief that exercise provides health benefits, as well as realistic information about disease severity.

Effect of dance therapy on blood pressure and exercise capacity of individuals with hypertension: A systematic review and meta-analysis.

PubMed

Conceição, Lino Sergio Rocha; Neto, Mansueto Gomes; do Amaral, Mayra Alves Soares; Martins-Filho, Paulo Ricardo Saquete; Oliveira Carvalho, Vitor

2016-10-01

Dance therapy is a less conventional modality of physical activity in cardiovascular rehabilitation. We performed a systematic review and meta-analysis to investigate the effects of dance therapy in hypertensive patients. Pubmed, Scopus, LILACS, IBECS, MEDLINE and SciELO via Virtual Health Library (Bireme) (from the earliest data available to February 2016) for controlled trials that investigated the effects of dance therapy on exercise capacity, systolic (SBP) and diastolic (DBP) blood pressure in hypertensive patients. Weighted mean differences (WMD) and 95% confidence intervals (CIs) were calculated, and heterogeneity was assessed using the I(2) test. Four studies met the eligibility criteria. Dance therapy resulted in a significant reduction in systolic blood pressure (WMD -12.01mmHg; 95% CI: -16.08, -7.94mmHg; P<0.0001) when compared with control subjects. Significant reduction in diastolic blood pressure were also found (WMD -3.38mmHg; 95% CI: -4.81, -1.94mmHg; P<0.0001), compared with control group. Exercise capacity showed a significant improvement (WMD 1.31; 95% CI: 0.16, 2.47; P<0.03). A moderate to high heterogeneity was observed in our analysis: I(2)=92% to SBP, I(2)=55% to DBP, and I(2)=82% to exercise capacity. Our meta-analysis showed a positive effect of dance therapy on exercise capacity and reduction of SBP and DBP in individuals with hypertension. However, the moderate to high heterogeneity found in our analysis limits a pragmatic recommendation of dance therapy in individuals with hypertension. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The effects of strength training on cognitive performance in elderly women.

PubMed

Smolarek, André de Camargo; Ferreira, Luis Henrique Boiko; Mascarenhas, Luis Paulo Gomes; McAnulty, Steven R; Varela, Karla Daniele; Dangui, Mônica C; de Barros, Marcelo Paes; Utter, Alan C; Souza-Junior, Tácito P

2016-01-01

Aging is a degenerative process marked by recognized functional, physiological, and metabolic impairments, such as dynapenia and diminished cognitive capacity. Therefore, the search for innovative strategies to prevent/delay these physiological and cognitive disorders is essential to guarantee the independence and life quality of an elderly population. The aim of this work is to verify the effect of a 12-week resistance exercise program on the general physical aptitude and cognitive capacities of elderly and sedentary women. Twenty-nine women (65.87±5.69 years) were divided into two groups. The control group was composed of eight elderly women who met the same inclusion criteria of the study and the strength training group was composed of 29 elderly women who were subjected to a resistance exercise program defined by 12 upper and lower limb exercises combined in 3×10 repetitions with 1-minute interval between repetitions and two resting minutes between exercises (three times/week). Weight loads were fixed between 60% and 75% of the apparent 1 repetition maximum, which was estimated by the test of 10 maximum repetitions. The direct curl was performed for upper body strength evaluation with 2.3 kg dumbbells for 30 seconds, whereas the chair test was used for lower body evaluation (total sit-stand movements in 30 seconds). The cognitive capacities of subjects were evaluated by "The Montreal Cognitive Assessment" questionnaire. After 12 weeks, the elderly group showed significant increases in the average upper body strength (58%), lower body strength (68%), and cognitive capacity (19%). The present study demonstrated that regular resistance exercises could provide significant gains on the upper and lower body strength concomitant to positive improvements on cognitive capacities of elderly women, bringing enhanced life quality.

[Effect of disease severity on upper extremity muscle strength, exercise capacity, and activities of daily living in individuals with pulmonary arterial hypertension].

PubMed

Özcan Kahraman, Buse; Özsoy, İsmail; Acar, Serap; Özpelit, Ebru; Akdeniz, Bahri; Sevinç, Can; Savcı, Sema

2017-07-01

Pulmonary arterial hypertension (PAH) is a rare disease. Although muscle strength, exercise capacity, quality of life, and activities of daily living of patients with PAH are affected, it is not known how they are affected by disease severity. The purpose of the present study was to investigate effects of disease severity on upper extremity muscle strength, exercise capacity, and performance of activities of daily living in patients with PAH. Twenty-five patients with disease severity classified according to the New York Heart Association (NYHA) as functional class II (n=14) or class III (n=11) were included in the study. Upper-extremity exercise capacity and limitations in performing activities of daily living were assessed with 6-minute pegboard and ring test (6PBRT) and the Milliken activities of daily living scale (MAS), respectively. Shoulder flexion, elbow extension, elbow flexion muscle strength, and handgrip strength were measured with dynamometer. There were no significant differences in age, gender, body mass index, or mean pulmonary artery pressure between groups (p>0.05). The 6PBRT, MAS, and elbow flexion (right) and grip strength (right and left) results were significantly lower in NYHA III group than in NYHA II group (p=0.004, p=0.002, p=0.043, p=0.002 and p=0.003, respectively). There was no significant difference in shoulder flexion, elbow flexion (left), or elbow extension between groups (p>0.05). Results suggest that upper extremity exercise capacity, elbow flexion muscle strength (right), and handgrip strength decrease and that limitations in activities of daily living grow as disease severity increases in patients with PAH. When planning rehabilitation programs, disease severity should be considered and evaluations and treatments for the upper extremities should be included.

Impact of exercise on the functional capacity and pain of patients with knee osteoarthritis: a randomized clinical trial.

PubMed

Oliveira, Aline Mizusaki Imoto de; Peccin, Maria Stella; Silva, Kelson Nonato Gomes da; Teixeira, Lucas Emmanuel Pedro de Paiva; Trevisani, Virgínia Fernandes Moça

2012-12-01

Muscle weakness, especially of the quadriceps muscle, is one of the major musculoskeletal effects of knee osteoarthritis. Exercises are considered one of the main interventions in the conservative treatment of those patients. To assess the effectiveness of quadriceps strengthening exercises on functional capacity and symptoms related of knee osteoarthritis by use of the Timed Up and Go test (TUG), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Lequesne Index. One hundred patients were randomized into two groups: 1) Exercise Group (n = 50), which included stationary bicycle, hamstrings stretching, and quadriceps strengthening; 2) Instruction Group (n = 50), which received a manual with information about knee osteoarthritis and instructions on how to deal with knee symptoms in daily activities. The manual did not include exercise instructions. The Exercise Group showed statistically significant improvement regarding the TUG test, the WOMAC aspects of pain, function, and stiffness, and the Lequesne Index, as compared with the Instruction Group. Quadriceps strengthening exercises for eight weeks are effective to improve pain, function, and stiffness in patients with knee osteoarthritis.

Loss of strength capacity is associated with mortality, but resistance exercise training promotes only modest effects during cachexia progression.

PubMed

das Neves, Willian; Alves, Christiano Robles Rodrigues; de Almeida, Ney Robson; Guimarães, Fátima Lúcia Rodrigues; Ramires, Paulo Rizzo; Brum, Patricia Chakur; Lancha, Antonio Herbert

2016-10-15

Resistance exercise training (RET) has been adopted as non-pharmacological anti-catabolic strategy. However, the role of RET to counteract cancer cachexia is still speculative. This study aimed to verify whether short-term RET would counteract skeletal muscle wasting in a severe cancer cachexia rat model. Wistar rats were randomly allocated into four experimental groups; 1) untrained control rats (control), 2) rats submitted to RET (control+RET), 3) untrained rats injected with Walker 256 tumor cells in the bone marrow (tumor) and 4) rats injected with Walker 256 tumor cells in the bone marrow and submitted to RET (tumor+RET). Tumor group displayed skeletal muscle atrophy fifteen days post tumor cells injection as assessed by plantaris (-20.5%) and EDL (-20.0%) muscle mass. EDL atrophy was confirmed showing 43.8% decline in the fiber cross sectional area. Even though RET increased the lactate dehydrogenase protein content and fully restored phosphorylated form of 4EBP-1 to the control levels in skeletal muscle, it failed to rescue muscle morphology in tumor-bearing rats. Indeed, RET did not mitigated loss of muscle function, anorexia, tumor growth or mortality rate. However, loss of strength capacity (assessed by 1-RM test performance) demonstrated a negative correlation with rats' survival (p=0.02; r=0.40), suggesting that loss of strength capacity might predict cancer mortality. These results demonstrated that bone marrow injection of Walker 256 tumor cells in rats induces cancer cachexia, strength capacity is associated with cancer survival and short-term RET promotes only modest effects during cachexia progression. Copyright © 2016 Elsevier Inc. All rights reserved.

Robot-assisted gait training improves brachial–ankle pulse wave velocity and peak aerobic capacity in subacute stroke patients with totally dependent ambulation

PubMed Central

Han, Eun Young; Im, Sang Hee; Kim, Bo Ryun; Seo, Min Ji; Kim, Myeong Ok

2016-01-01

Abstract Objective: Brachial–ankle pulse wave velocity (baPWV) evaluates arterial stiffness and also predicts early outcome in stroke patients. The objectives of this study were to investigate arterial stiffness of subacute nonfunctional ambulatory stroke patients and to compare the effects of robot-assisted gait therapy (RAGT) combined with rehabilitation therapy (RT) on arterial stiffness and functional recovery with those of RT alone. Method: The RAGT group (N = 30) received 30 minutes of robot-assisted gait therapy and 30 minutes of conventional RT, and the control group (N = 26) received 60 minutes of RT, 5 times a week for 4 weeks. baPWV was measured and calculated using an automated device. The patients also performed a symptom-limited graded exercise stress test using a bicycle ergometer, and parameters of cardiopulmonary fitness were recorded. Clinical outcome measures were categorized into 4 categories: activities of daily living, balance, ambulatory function, and paretic leg motor function and were evaluated before and after the 4-week intervention. Results: Both groups exhibited significant functional recovery in all clinical outcome measures after the 4-week intervention. However, peak aerobic capacity, peak heart rate, exercise tolerance test duration, and baPWV improved only in the RAGT group, and the improvements in baPWV and peak aerobic capacity were more noticeable in the RAGT group than in the control group. Conclusion: Robot-assisted gait therapy combined with conventional rehabilitation therapy represents an effective method for reversing arterial stiffness and improving peak aerobic capacity in subacute stroke patients with totally dependent ambulation. However, further large-scale studies with longer term follow-up periods are warranted to measure the effects of RAGT on secondary prevention after stroke. PMID:27741123

Does self-assessed physical capacity predict development of low back pain among health care workers? A 2-year follow-up study.

PubMed

Rasmussen, Charlotte D N; Jørgensen, Marie B; Clausen, Thomas; Andersen, Lars L; Strøyer, Jesper; Holtermann, Andreas

2013-02-01

Prospective cohort study. To determine the prognostic value of self-assessed physical capacity for the development of low back pain (LBP) among female health care workers without LBP. High physical capacities in terms of strength, endurance, flexibility, and balance are assumed to prevent LBP among persons with high physical work demands. However, the few existing studies investigating this relationship show contrasting findings. Female health care workers answered a questionnaire about physical capacity in 2004, and days with LBP in 2005 and 2006. The odds ratios (ORs) for developing nonchronic (1-30 d of the past 12 mo) and persistent (>30 d of the past 12 mo) LBP in 2006 from self-assessed physical capacity were investigated with multiadjusted logistic regressions among female health care workers without LBP in 2005 (n = 1612). Health care workers with low and medium physical capacity had increased risk of developing nonchronic LBP (OR = 1.52 [CI = 1.05-2.20] and OR = 1.37 [CI = 1.01-1.84], respectively), and health care workers with low physical capacity had an increased risk of developing persistent LBP (OR = 2.13 [CI = 1.15-3.96]), referencing those with high physical capacity. Self-assessed low physical capacity is a strong predictor for developing nonchronic and persistent LBP among pain-free female health care workers. Future intervention studies should investigate whether increased physical capacity, for example, through exercise training prevents development of LBP among female health care workers.

Statins Affect Skeletal Muscle Performance: Evidence for Disturbances in Energy Metabolism.

PubMed

Allard, Neeltje A E; Schirris, Tom J J; Verheggen, Rebecca J; Russel, Frans G M; Rodenburg, Richard J; Smeitink, Jan A M; Thompson, Paul D; Hopman, Maria T E; Timmers, Silvie

2018-01-01

Statin myopathy is linked to disturbances in mitochondrial function and exercise intolerance. To determine whether differences exist in exercise performance, muscle function, and muscle mitochondrial oxidative capacity and content between symptomatic and asymptomatic statin users, and control subjects. Cross-sectional study. Department of Physiology, Radboud University Medical Center. Long-term symptomatic and asymptomatic statin users, and control subjects (n = 10 per group). Maximal incremental cycling tests, involuntary electrically stimulated isometric quadriceps-muscle contractions, and biopsy of vastus lateralis muscle. Maximal exercise capacity, substrate use during exercise, muscle function, and mitochondrial energy metabolism. Peak oxygen uptake, maximal work load, and ventilatory efficiency were comparable between groups, but both statin groups had a depressed anaerobic threshold compared with the control group (P = 0.01). Muscle relaxation time was prolonged in both statin groups compared with the control group and rate of maximal force rise was decreased (Ptime×group < 0.001 for both measures). Mitochondrial activity of complexes II and IV was lower in symptomatic statin users than control subjects and tended to be lower for complex (C) III (CII: P = 0.03; CIII: P = 0.05; CIV: P = 0.04). Mitochondrial content tended to be lower in both statin groups than in control subjects. Statin use attenuated substrate use during maximal exercise performance, induced muscle fatigue during repeated muscle contractions, and decreased muscle mitochondrial oxidative capacity. This suggests disturbances in mitochondrial oxidative capacity occur with statin use even in patients without statin-induced muscle complaints. Copyright © 2017 Endocrine Society

Low haemoglobin concentration in Tibetan males is associated with greater high-altitude exercise capacity.

PubMed

Simonson, T S; Wei, G; Wagner, H E; Wuren, T; Qin, G; Yan, M; Wagner, P D; Ge, R L

2015-07-15

Tibetans living at high altitude have adapted genetically such that many display a low erythropoietic response, resulting in near sea-level haemoglobin (Hb) concentration. We hypothesized that absence of the erythropoietic response would be associated with greater exercise capacity compared to those with high [Hb] as a result of beneficial changes in oxygen transport. We measured, in 21 Tibetan males with [Hb] ranging from 15.2 g dl(-1) to 22.9 g dl(-1) (9.4 mmol l(-1) to 14.2 mmol l(-1) ), [Hb], ventilation, volumes of O2 and CO2 utilized at peak exercise (V̇O2 and V̇CO2), heart rate, cardiac output and arterial blood gas variables at peak exercise on a cycle ergometer at ∼4200 m. Lung and muscle O2 diffusional conductances were computed from these measurements. [Hb] was related (negatively) to V̇O2 kg(-1) (r = -0.45, P< 0.05), cardiac output kg(-1) (QT kg(-1) , r = -0.54, P < 0.02), and O2 diffusion capacity in muscle (DM kg(-1) , r = -0.44, P<0.05), but was unrelated to ventilation, arterial partial pressure of O2 (PaO2) or pulmonary diffusing capacity. Using multiple linear regression, variance in peak V̇O2 kg(-1) was primarily attributed to QT, DM, and PCO2 (R(2) = 0.88). However, variance in pulmonary gas exchange played essentially no role in determining peak V̇O2. These results (1) show higher exercise capacity in Tibetans without the erythropoietic response, supported mostly by cardiac and muscle O2 transport capacity and ventilation rather than pulmonary adaptations, and (2) support the emerging hypothesis that the polycythaemia of altitude, normally a beneficial response to low cellular PO2, may become maladaptive if excessively elevated under chronic hypoxia. The cause and effect relationships among [Hb], QT, DM, and PCO2 remain to be elucidated. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

Effects of chronic nitric oxide synthase inhibition on V'O2max and exercise capacity in mice.

PubMed

Wojewoda, M; Przyborowski, K; Sitek, B; Zakrzewska, A; Mateuszuk, L; Zoladz, J A; Chlopicki, S

2017-03-01

Acute inhibition of NOS by L-NAME (N ω -nitro-L-arginine methyl ester) is known to decrease maximal oxygen consumption (V'O 2max ) and impair maximal exercise capacity, whereas the effects of chronic L-NAME treatment on V'O 2max and exercise performance have not been studied so far. In this study, we analysed the effect of L-NAME treatment, (LN2 and LN12, respectively) on V'O 2max and exercise capacity (in maximal incremental running and prolonged sub-maximal incremental running tests), systemic NO bioavailability (plasma nitrite (NO 2 - ) and nitrate (NO 3 - )) and prostacyclin (PGI 2 ) production in C57BL6/J mice. Mice treated with L-NAME for 2 weeks (LN2) displayed higher V'O 2max and better running capacity than age-matched control mice. In LN2 mice, NO bioavailability was preserved, as evidenced by maintained NO 2 - plasma concentration. PGI 2 production was activated (increased 6-keto-PGF 1α plasma concentration) and the number of circulating erythrocytes (RBC) and haemoglobin concentration were increased. In mice treated with L-NAME for 12 weeks (LN12), NO bioavailability was decreased (lower NO 2 - plasma concentration), and 6-keto-PGF 1α plasma concentration and RBC number were not elevated compared to age-matched control mice. However, LN12 mice still performed better during the maximal incremental running test despite having lower V'O 2max . Interestingly, the LN12 mice showed poorer running capacity during the prolonged sub-maximal incremental running test. To conclude, short-term (2 weeks) but not long-term (12 weeks) treatment with L-NAME activated robust compensatory mechanisms involving preservation of NO2- plasma concentration, overproduction of PGI 2 and increased number of RBCs, which might explain the fully preserved exercise capacity despite the inhibition of NOS.

Association between Functional Capacity Decline and Nutritional Status Based on the Nutrition Screening Initiative Checklist: A 2-Year Cohort Study of Japanese Community-Dwelling Elderly.

PubMed

Sugiura, Yumiko; Tanimoto, Yoshimi; Imbe, Ayumi; Inaba, Yuiko; Sakai, Satoshi; Shishikura, Kanako; Tanimoto, Keiji; Hanafusa, Toshiaki

2016-01-01

To assess whether nutritional status based on the Nutrition Screening Initiative Checklist is useful for predicting functional capacity decline in community-dwelling Japanese elderly. This two-year observational cohort study included 536 community-dwelling Japanese (65 years and older at baseline) who were independent in both activities and instrumental activities of daily living. Demographic attributes, chronic illness, lifestyle-related habits, nutritional status, functional capacity, and anthropometric measurements were assessed, with decline in functional capacity used as the outcome measure. Subjects were classified into three groups as follows based on the Nutrition Screening Initiative Checklist: low (59.5%), moderate (23.7%), and high (16.8%) nutritional risk. Significant differences were found between nutritional status and the following four baseline variables: age, hypertension, cerebrovascular diseases, and current smoking. However, no significant differences were evident between nutritional status and sex, body mass index, diabetes, drinking habit, or exercise habit. Logistic regression analysis adjusted for age, sex, body mass index, hypertension, cerebrovascular diseases and smoking habit showed that the high nutritional risk group was significantly associated with a decline in both activities of daily living (odds ratio: 4.96; 95% confidence interval (CI): 1.59-15.50) and instrumental activities of daily living (OR: 2.58; 95% CI: 1.31-5.06) compared with the low nutritional risk group. Poor nutritional status based on the Nutrition Screening Initiative Checklist was associated with a decline in functional capacity over a 2-year period in community-dwelling Japanese elderly. These results suggest that the Nutrition Screening Initiative Checklist is a suitable tool for predicting functional capacity decline in community-dwelling elderly.

The 12-week progressive quadriceps resistance training improves muscle strength, exercise capacity and quality of life in patients with stable chronic heart failure.

PubMed

Jankowska, Ewa A; Wegrzynowska, Kinga; Superlak, Malgorzata; Nowakowska, Katarzyna; Lazorczyk, Malgorzata; Biel, Bartosz; Kustrzycka-Kratochwil, Dorota; Piotrowska, Katarzyna; Banasiak, Waldemar; Wozniewski, Marek; Ponikowski, Piotr

2008-10-30

Abnormalities in the skeletal musculature underlie exercise intolerance in chronic heart failure (CHF). We investigated, whether in CHF selective resistance training without accompanying aerobic regime favourably affects muscle strength, muscle mass and improves exercise capacity. Ten patients with stable ischaemic CHF in NYHA class III (9 men, age: 70+/-6 years [mean+/-SD], left ventricular ejection fraction: 30+/-5%, peak oxygen consumption [peak VO(2)]: 12.4+/-3.0 mL/min/kg) underwent the rehabilitation programme which consisted of a 12-week training phase (progressive resistance exercises restricted to the quadriceps muscles) followed by a 12-week detraining phase. All subjects completed a training phase of the programme with no adverse events. Resistance training markedly increased quadriceps strength (right leg: 260+/-34 vs. 352+/-28 N, left leg: 264+/-38 vs. 342+/-30 N, both p<0.01 - all comparisons: baseline vs. after training), but did not affect lean tissue mass of lower extremities (both p>0.2). It was accompanied by an improvement in clinical status (all NYHA III vs. all NYHA II, p<0.01), quality of life (Minnesota questionnaire: 44+/-15 vs. 33+/-18 points, p<0.05), exercise capacity assessed using a distance during 6-minute walk test (6MWT: 362+/-83 vs. 455+/-71 m, p<0.01), but not peak VO(2) (p>0.2). Plasma NT-proBNP remained unchanged during the training. At the end of detraining phase, only a partial improvement in quadriceps strength (p<0.05), a 6MWT distance (p<0.05) and NYHA class (p=0.07 vs. baseline) persisted. Applied resistance quadriceps training is safe in patients with CHF. It increases muscle strength, improves clinical status, exercise capacity, and quality of life.

Effects of exercise on fatigue, sleep, and performance: a randomized trial.

PubMed

Coleman, Elizabeth Ann; Goodwin, Julia A; Kennedy, Robert; Coon, Sharon K; Richards, Kathy; Enderlin, Carol; Stewart, Carol B; McNatt, Paula; Lockhart, Kim; Anaissie, Elias J

2012-09-01

To compare usual care with a home-based individualized exercise program (HBIEP) in patients receiving intensive treatment for multiple myeloma (MM)and epoetin alfa therapy. Randomized trial with repeated measures of two groups (one experimental and one control) and an approximate 15-week experimental period. Outpatient setting of the Myeloma Institute for Research and Therapy at the Rockfellow Cancer Center at the University of Arkansas for Medical Sciences. 187 patients with newly diagnosed MM enrolled in a separate study evaluating effectiveness of the Total Therapy regimen, with or without thalidomide. Measurements included the Profile of Mood States fatigue scale, Functional Assessment of Cancer Therapy-Fatigue, ActiGraph® recordings, 6-Minute Walk Test, and hemoglobin levels at baseline and before and after stem cell collection. Descriptive statistics were used to compare demographics and treatment effects, and repeated measures analysis of variance was used to determine effects of HBIEP. Fatigue, nighttime sleep, performance (aerobic capacity) as dependent or outcome measures, and HBIEP combining strength building and aerobic exercise as the independent variable. Both groups were equivalent for age, gender, race, receipt of thalidomide, hemoglobin levels, and type of treatment regimen for MM. No statistically significant differences existed among the experimental and control groups for fatigue, sleep, or performance (aerobic capacity). Statistically significant differences (p < 0.05) were found in each of the study outcomes for all patients as treatment progressed and patients experienced more fatigue and poorer nighttime sleep and performance (aerobic capacity). The effect of exercise seemed to be minimal on decreasing fatigue, improving sleep, and improving performance (aerobic capacity). Exercise is safe and has physiologic benefits for patients undergoing MM treatment; exercise combined with epoetin alfa helped alleviate anemia.

Longitudinal relationship between wheelchair exercise capacity and life satisfaction in patients with spinal cord injury: A cohort study in the Netherlands.

PubMed

van Koppenhagen, Casper Floris; Post, Marcel; de Groot, Sonja; van Leeuwen, Christel; van Asbeck, Floris; Stolwijk-Swüste, Janneke; van der Woude, Lucas; Lindeman, Eline

2014-05-01

To examine the relationship between wheelchair exercise capacity and life satisfaction in persons with spinal cord injury from the start of active inpatient rehabilitation up to 5 years after discharge. Prospective cohort study. Persons with spinal cord injury, aged 18-65 years, and wheelchair dependent at least for long distances. Measurements at the start of active rehabilitation, after 3 months, at discharge from inpatient rehabilitation, and 1 and 5 years after discharge. A peak wheelchair exercise test was performed to record peak oxygen uptake (VO2peak) and peak power output (POpeak). Life satisfaction was measured as current life satisfaction and change of life satisfaction in comparison with life after spinal cord injury. Relationships between (changes in) exercise capacity and (changes in) life satisfaction were analyzed random coefficient analysis, corrected for possible confounders (age, gender, level of lesion, functional status, secondary impairments, pain, and sports activity) if necessary. Of 225 persons included, 130 attended two or more peak exercise tests, who were include in the analyses. Mean age at start was 39 years, 75% were male, 73% had paraplegia, and 76% had a traumatic lesion. Mean POpeak increased during the study from 32.9 to 55.9 Watts, mean VO2peak from 1.02 to 1.38 l/minute, and mean life satisfaction from 5.7 to 7.8. An increase of POpeak with 10 W was associated with a 0.3-point increase of life satisfaction (P = 0.01). An increase of VO2peak with 0.1 l/minute was associated with a 0.1-point increase of life satisfaction (P = 0.049). Conclusion High(er) wheelchair exercise capacity is related to high(er) life satisfaction in spinal cord injury patients.

Tocotrienols and Whey Protein Isolates Substantially Increase Exercise Endurance Capacity in Diet -Induced Obese Male Sprague-Dawley Rats

PubMed Central

Aguila, Jay; McConell, Glenn K.; McAinch, Andrew J.; Mathai, Michael L.

2016-01-01

Background and Aims Obesity and impairments in metabolic health are associated with reductions in exercise capacity. Both whey protein isolates (WPIs) and vitamin E tocotrienols (TCTs) exert favorable effects on obesity-related metabolic parameters. This research sought to determine whether these supplements improved exercise capacity and increased glucose tolerance in diet-induced obese rats. Methods Six week old male rats (n = 35) weighing 187 ± 32g were allocated to either: Control (n = 9), TCT (n = 9), WPI (n = 8) or TCT + WPI (n = 9) and placed on a high-fat diet (40% of energy from fat) for 10 weeks. Animals received 50mg/kg body weight and 8% of total energy intake per day of TCTs and/or WPIs respectively. Food intake, body composition, glucose tolerance, insulin sensitivity, exercise capacity, skeletal muscle glycogen content and oxidative enzyme activity were determined. Results Both TCT and WPI groups ran >50% longer (2271 ± 185m and 2195 ± 265m respectively) than the Control group (1428 ± 139m) during the run to exhaustion test (P<0.05), TCT + WPI did not further improve exercise endurance (2068 ± 104m). WPIs increased the maximum in vitro activity of beta-hydroxyacyl-CoA in the soleus muscle (P<0.05 vs. Control) but not in the plantaris. Citrate synthase activity was not different between groups. Neither supplement had any effect on weight gain, adiposity, glucose tolerance or insulin sensitivity. Conclusion Ten weeks of both TCTs and WPIs increased exercise endurance by 50% in sedentary, diet-induced obese rats. These positive effects of TCTs and WPIs were independent of body weight, adiposity or glucose tolerance. PMID:27058737

The effects of running exercise on oxidative capacity and PGC-1α mRNA levels in the soleus muscle of rats with metabolic syndrome.

PubMed

Nagatomo, Fumiko; Fujino, Hidemi; Kondo, Hiroyo; Kouzaki, Motoki; Gu, Ning; Takeda, Isao; Tsuda, Kinsuke; Ishihara, Akihiko

2012-03-01

Skeletal muscles in animals with metabolic syndrome exhibit reduced oxidative capacity. We investigated the effects of running exercise on fiber characteristics, oxidative capacity, and mRNA levels in the soleus muscles of rats with metabolic syndrome [SHR/NDmcr-cp (cp/cp); CP]. We divided 5-week-old CP rats into non-exercise (CP) and exercise (CP-Ex) groups. Wistar-Kyoto rats (WKY) were used as the control group. CP-Ex rats were permitted voluntary exercise on running wheels for 10 weeks. Triglyceride levels were higher and adiponectin levels lower in the CP and CP-Ex groups than in the WKY group. However, triglyceride levels were lower and adiponectin levels higher in the CP-Ex group than in the CP group. The soleus muscles in CP-Ex rats contained only high-oxidative type I fibers, whereas those in WKY and CP rats contained type I, IIA, and IIC fibers. Muscle succinate dehydrogenase (SDH) activity was higher in the CP-Ex group than in the CP group; there was no difference in SDH activity between the WKY and CP-Ex groups. Muscle proliferator-activated receptor γ coactivator-1α (PGC-1α) mRNA levels were higher in the CP-Ex group than in the CP group; there was no difference in PGC-1α mRNA levels between the WKY and CP-Ex groups. In CP-Ex rats, longer running distance was associated with increased muscle SDH activity and PGC-1α mRNA levels. We concluded that running exercise restored decreased muscle oxidative capacity and PGC-1α mRNA levels and improved hypertriglyceridemia in rats with metabolic syndrome.

Selection-, age-, and exercise-dependence of skeletal muscle gene expression patterns in a rat model of metabolic fitness.

PubMed

Ren, Yu-Yu; Koch, Lauren G; Britton, Steven L; Qi, Nathan R; Treutelaar, Mary K; Burant, Charles F; Li, Jun Z

2016-11-01

Intrinsic aerobic exercise capacity can influence many complex traits including obesity and aging. To study this connection we established two rat lines by divergent selection of untrained aerobic capacity. After 32 generations the high capacity runners (HCR) and low capacity runners (LCR) differed in endurance running distance and body fat, blood glucose, other health indicators, and natural life span. To understand the interplay among genetic differences, chronological age, and acute exercise we performed microarray-based gene expression analyses in skeletal muscle with a 2×2×2 design to simultaneously compare HCR and LCR, old and young animals, and rest and exhaustion. Transcripts for mitochondrial function are expressed higher in HCRs than LCRs at both rest and exhaustion and for both age groups. Expression of cell adhesion and extracellular matrix genes tend to decrease with age. This and other age effects are more prominent in LCRs than HCRs, suggesting that HCRs have a slower aging process and this may be partly due to their better metabolic health. Strenuous exercise mainly affects transcription regulation and cellular response. The effects of any one factor often depend on the other two. For example, there are ∼140 and ∼110 line-exercise "interacting" genes for old and young animals, respectively. Many genes highlighted in our study are consistent with prior reports, but many others are novel. The gene- and pathway-level statistics for the main effects, either overall or stratified, and for all possible interactions, represent a rich reference dataset for understanding the interdependence among lines, aging, and exercise. Copyright © 2016 the American Physiological Society.

Effects of maximum intensity aerobic swimming exercise until exhaustion at different times of day on the hematological parameters in rats.

PubMed

Beck, W; Gobatto, Claudio Alexandre

2013-12-01

The aims of this study were: a) to analyze the time of day effect on the aerobic capacity and time to exhaustion at aerobic capacity intensity (TE), and b) to analyze the physiological impact of handling and exercise testing during the light and dark periods, based on hematological parameters. Eighty rats were randomly divided into two control groups (C12 and C20) and two exercise groups (E12 and E20), assessed at 12:00 h (C12 and E12) or 20:00 h (C20 and E20). The lactate minimum intensity (LMi) was measured and after 48 h the exercise groups were subjected to a bout of swimming until exhaustion at LMi (TE). The TE was 1.30 ± 0.51 h for the E12 group and 1.81 ± 0.77 h for the E20 group (p = 0.03). The time of day effect was significant for all white blood cell counts (12:00 h > 20:00 h). Chronic handling and performing exercise tests at 12:00 h (light period) resulted in an increased WBC counts and decreased exercise tolerance. The favorable time of day for aerobic capacity and performance assessment and hematological parameters was at 20:00 h (dark period), which is associated with the wakefulness period of the assessed animals.

Comparison of three different approaches in the treatment of chronic low back pain.

PubMed

Koldaş Doğan, Sebnem; Sonel Tur, Birkan; Kurtaiş, Yeşim; Atay, Mesut Birol

2008-07-01

Our aim is to investigate the effects of three therapeutic approaches in the chronic low back pain on pain, spinal mobility, disability, psychological state, and aerobic capacity. Sixty patients with chronic low back pain were randomized to three groups: group 1, aerobic exercise + home exercise; group 2, physical therapy (hot pack, ultrasound, TENS) + home exercise; group 3, home exercise only. Spinal mobility, pain severity, disability, and psychological disturbance of the patients were assessed before and after the treatment and at 1-month follow-up. Aerobic capacities of the patients were measured before and after treatment. All of the groups showed similar decrease in pain after the treatment and at 1-month follow-up, and there was no significant difference between the groups. In group 2, a significant decrease in Beck Depression Inventory scores was observed with treatment. At 1-month follow-up, group 1 and 2 showed significant decreases in General Health Assessment Questionnaire scores. In group 2, there was also a significant improvement in Roland Morris Disability scores. There were similar improvements in exercise test duration and the MET levels in all the three groups. All of the three therapeutic approaches were found to be effective in diminishing pain and thus increasing aerobic capacity in patients with chronic low back pain. On the other hand, physical therapy + home exercise was found to be more effective regarding disability and psychological disturbance.

Exercise-based cardiac rehabilitation for adults with atrial fibrillation.

PubMed

Risom, Signe S; Zwisler, Ann-Dorthe; Johansen, Pernille P; Sibilitz, Kirstine L; Lindschou, Jane; Gluud, Christian; Taylor, Rod S; Svendsen, Jesper H; Berg, Selina K

2017-02-09

Exercise-based cardiac rehabilitation may benefit adults with atrial fibrillation or those who had been treated for atrial fibrillation. Atrial fibrillation is caused by multiple micro re-entry circuits within the atrial tissue, which result in chaotic rapid activity in the atria. To assess the benefits and harms of exercise-based rehabilitation programmes, alone or with another intervention, compared with no-exercise training controls in adults who currently have AF, or have been treated for AF. We searched the following electronic databases; CENTRAL and the Database of Abstracts of Reviews of Effectiveness (DARE) in the Cochrane Library, MEDLINE Ovid, Embase Ovid, PsycINFO Ovid, Web of Science Core Collection Thomson Reuters, CINAHL EBSCO, LILACS Bireme, and three clinical trial registers on 14 July 2016. We also checked the bibliographies of relevant systematic reviews identified by the searches. We imposed no language restrictions. We included randomised controlled trials (RCT) that investigated exercise-based interventions compared with any type of no-exercise control. We included trials that included adults aged 18 years or older with atrial fibrillation, or post-treatment for atrial fibrillation. Two authors independently extracted data. We assessed the risk of bias using the domains outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We assessed clinical and statistical heterogeneity by visual inspection of the forest plots, and by using standard Chi² and I² statistics. We performed meta-analyses using fixed-effect and random-effects models; we used standardised mean differences where different scales were used for the same outcome. We assessed the risk of random errors with trial sequential analysis (TSA) and used the GRADE methodology to rate the quality of evidence, reporting it in the 'Summary of findings' table. We included six RCTs with a total of 421 patients with various types of atrial fibrillation. All trials were conducted between 2006 and 2016, and had short follow-up (eight weeks to six months). Risks of bias ranged from high risk to low risk.The exercise-based programmes in four trials consisted of both aerobic exercise and resistance training, in one trial consisted of Qi-gong (slow and graceful movements), and in another trial, consisted of inspiratory muscle training.For mortality, very low-quality evidence from six trials suggested no clear difference in deaths between the exercise and no-exercise groups (relative risk (RR) 1.00, 95% confidence interval (CI) 0.06 to 15.78; participants = 421; I² = 0%; deaths = 2). Very low-quality evidence from five trials suggested no clear difference between groups for serious adverse events (RR 1.01, 95% CI 0.98 to 1.05; participants = 381; I² = 0%; events = 8). Low-quality evidence from two trials suggested no clear difference in health-related quality of life for the Short Form-36 (SF-36) physical component summary measure (mean difference (MD) 1.96, 95% CI -2.50 to 6.42; participants = 224; I² = 69%), or the SF-36 mental component summary measure (MD 1.99, 95% CI -0.48 to 4.46; participants = 224; I² = 0%). Exercise capacity was assessed by cumulated work, or maximal power (Watt), obtained by cycle ergometer, or by six minute walking test, or ergospirometry testing measuring VO2 peak. We found moderate-quality evidence from two studies that exercise-based rehabilitation increased exercise capacity, measured by VO2 peak, more than no exercise (MD 3.76, 95% CI 1.37 to 6.15; participants = 208; I² = 0%); and very low-quality evidence from four studies that exercise-based rehabilitation increased exercise capacity more than no exercise, measured by the six-minute walking test (MD 75.76, 95% CI 14.00 to 137.53; participants = 272; I² = 85%). When we combined the different assessment tools for exercise capacity, we found very low-quality evidence from six trials that exercise-based rehabilitation increased exercise capacity more than no exercise (standardised mean difference (SMD) 0.86, 95% CI 0.46 to 1.26; participants = 359; I² = 65%). Overall, the quality of the evidence for the outcomes ranged from moderate to very-low. Due to few randomised patients and outcomes, we could not evaluate the real impact of exercise-based cardiac rehabilitation on mortality or serious adverse events. The evidence showed no clinically relevant effect on health-related quality of life. Pooled data showed a positive effect on the surrogate outcome of physical exercise capacity, but due to the low number of patients and the moderate to very low-quality of the underpinning evidence, we could not be certain of the magnitude of the effect. Future high-quality randomised trials are needed to assess the benefits and harms of exercise-based cardiac rehabilitation for adults with atrial fibrillation on patient-relevant outcomes.

Improvement in exercise performance by inhalation of methoxamine in patients with impaired left ventricular function.

PubMed

Cabanes, L; Costes, F; Weber, S; Regnard, J; Benvenuti, C; Castaigne, A; Guerin, F; Lockhart, A

1992-06-18

Bronchial hyperresponsiveness to cholinergic stimuli such as the inhalation of methacholine is common in patients with impaired left ventricular function. Such hyperresponsiveness is best explained by cholinergic vasodilation of blood vessels in the small airways, with extravasation of plasma due to high left ventricular filling pressure. Because this vasodilation may be prevented by the inhalation of the vasoconstrictor agent methoxamine, we studied the effect of methoxamine on exercise performance in patients with chronic left ventricular dysfunction. We studied 19 patients with a mean left ventricular ejection fraction of 22 +/- 4 percent and moderate exertional dyspnea. In the first part of the study, we performed treadmill exercise tests in 10 patients (group 1) at a constant maximal workload to assess the effects of 10 mg of inhaled methoxamine on the duration of exercise (a measure of endurance). In the second part of the study, we used a graded exercise protocol in nine additional patients (group 2) to assess the effects of inhaled methoxamine on maximal exercise capacity and oxygen consumption. Both studies were carried out after the patients inhaled methoxamine or placebo given according to a randomized, double-blind, crossover design. In group 1, the mean (+/- SD) duration of exercise increased from 293 +/- 136 seconds after the inhalation of placebo to 612 +/- 257 seconds after the inhalation of methoxamine (P = 0.001). In group 2, exercise time (a measure of maximal exercise capacity) increased from 526 +/- 236 seconds after placebo administration to 578 +/- 255 seconds after methoxamine (P = 0.006), and peak oxygen consumption increased from 18.5 +/- 6.0 to 20.0 +/- 6.0 ml per minute per kilogram of body weight (P = 0.03). The inhalation of methoxamine enhanced exercise performance in patients with chronic left ventricular dysfunction. However, the improvement in the duration of exercise at a constant workload (endurance) was much more than the improvement in maximal exercise capacity assessed with a progressive workload. These data suggest that exercise-induced vasodilation of airway vessels may contribute to exertional dyspnea in such patients. Whether or not inhaled methoxamine can provide long-term benefit in patients with heart failure will require further study.

Exercise Prevents Enhanced Postoperative Neuroinflammation and Cognitive Decline and Rectifies the Gut Microbiome in a Rat Model of Metabolic Syndrome.

PubMed

Feng, Xiaomei; Uchida, Yosuke; Koch, Lauren; Britton, Steve; Hu, Jun; Lutrin, David; Maze, Mervyn

2017-01-01

Postoperative cognitive decline (PCD) can affect in excess of 10% of surgical patients and can be considerably higher with risk factors including advanced age, perioperative infection, and metabolic conditions such as obesity and insulin resistance. To define underlying pathophysiologic processes, we used animal models including a rat model of metabolic syndrome generated by breeding for a trait of low aerobic exercise tolerance. After 35 generations, the low capacity runner (LCR) rats differ 10-fold in their aerobic exercise capacity from high capacity runner (HCR) rats. The LCR rats respond to surgical procedure with an abnormal phenotype consisting of exaggerated and persistent PCD and failure to resolve neuroinflammation. We determined whether preoperative exercise can rectify the abnormal surgical phenotype. Following institutional approval of the protocol each of male LCR and male HCR rats were randomly assigned to four groups and subjected to isoflurane anesthesia and tibia fracture with internal fixation (surgery) or anesthesia alone (sham surgery) and to a preoperative exercise regimen that involved walking for 10 km on a treadmill over 6 weeks (exercise) or being placed on a stationary treadmill (no exercise). Feces were collected before and after exercise for assessment of gut microbiome. Three days following surgery or sham surgery the rats were tested for ability to recall a contextual aversive stimulus in a trace fear conditioning paradigm. Thereafter some rats were euthanized and the hippocampus harvested for analysis of inflammatory mediators. At 3 months, the remainder of the rats were tested for memory recall by the probe test in a Morris Water Maze. Postoperatively, LCR rats exhibited exaggerated cognitive decline both at 3 days and at 3 months that was prevented by preoperative exercise. Similarly, LCR rats had excessive postoperative neuroinflammation that was normalized by preoperative exercise. Diversity of the gut microbiome in the LCR rats improved after exercise. Preoperative exercise eliminated the metabolic syndrome risk for the abnormal surgical phenotype and was associated with a more diverse gut microbiome. Prehabilitation with exercise should be considered as a possible intervention to prevent exaggerated and persistent PCD in high-risk settings.

Multivisceral Transplantation Rehabilitation Program-Case Report.

PubMed

Loschi, T M; Cinacchi, M P R G; Baccan, M D T A; Marques, F; Pedroso, P T; Meira Filho, S P; Scacchetti, T; Pavão, D N

2018-04-01

Multivisceral transplantation is the treatment for multiple abdominal organ failure. The patient experiences reduced food intake and absorption of nutrients, contributing to weight loss and decreased muscle mass, reducing functional capacity. A physical and nutritional rehabilitation program based on adequate caloric intake associated with supervised physical exercise seems to support a gain of muscle mass, re-establishing its capacity and functional independence. A rehabilitation program was carried out, consisting of low-intensity aerobic exercise on treadmill, exercises of global strengthening (50% of 1 maximum repetition [1RM], with progressive increase), and nutritional monitoring (oral hypercaloric diet, hyperproteic supplementation daily and after exercise). Initial and final evaluation included weight, muscle mass index, brachial circumference (BC), tricipital cutaneous fold (TCF), hand grip strength (HGS), 6-minute walk test (6MWT), 1RM, vital capacity (VC), and respiratory muscle strength. After the program, functional capacity was evaluated through the 6MWT (92%), 1RM test, VC (55%), respiratory muscle strength, HGS at 5 kg, weight gain (4.75%), increase of BC in 2 cm, and TCF in 2 mm. The program contributed to functional independence, improved quality of life, and social reintegration, suggesting the importance of a supervised physical activity program associated with adequate nutritional intake after multivisceral transplantation. Copyright © 2018 Elsevier Inc. All rights reserved.

Fat-Free Mass Index for Evaluating the Nutritional Status and Disease Severity in COPD.

PubMed

Luo, Yuwen; Zhou, Luqian; Li, Yun; Guo, Songwen; Li, Xiuxia; Zheng, Jingjing; Zhu, Zhe; Chen, Yitai; Huang, Yuxia; Chen, Rui; Chen, Xin

2016-05-01

Despite the high prevalence of weight loss in subjects with COPD, the 2011 COPD management guidelines do not include an index measuring nutritional status. Fat-free mass index (FFMI) can accurately determine the nutritional status of subjects and may be closely correlated with COPD severity. We aimed to determine the nutritional status evaluated by FFMI according to the 2011 Global Initiative for Chronic Obstructive Lung Disease (GOLD) levels in stable subjects with COPD and the association between nutritional status and respiratory symptoms, exercise capacity, and respiratory muscle function. We included 235 stable subjects with COPD in this cross-sectional study. All of the subjects were divided into the 2011 GOLD Groups A, B, C, and D. FFMI (measured by bioelectrical impedance), spirometry (FEV1, percent-of-predicted FEV1, and FEV1/FVC), respiratory muscle function (peak inspiratory and peak expiratory pressures), exercise capacity (6-min walk distance), and dyspnea severity (Modified Medical Research Council dyspnea scale) were measured and compared between the GOLD groups. Malnutrition was identified in 48.5% of subjects and most prevalent in Group D (Group A: 41%, Group B: 41%, Group C: 31%, and Group D: 62%). FFMI was significantly lower in Group D (P < .001), with both sexes considered malnourished. Low FFMI significantly correlated with frequent exacerbation, older age, decreased pulmonary function, 6-min walk distance, peak inspiratory pressure, and worsened dyspnea. FFMI was significantly lower in the emphysema-dominant phenotype and mixed phenotype compared with the normal phenotype and airway-dominant phenotype. A stepwise multiple linear regression analysis identified peak inspiratory pressures and older age as independent predictors of FFMI. Malnutrition is highly prevalent in all COPD groups, particularly in Group D subjects, who warrant special attention for nutritional intervention and pulmonary rehabilitation. FFMI significantly correlated with exercise capacity, dyspnea, respiratory muscle function, and pulmonary function and may be a useful predictor of COPD severity. Copyright © 2016 by Daedalus Enterprises.

Effectiveness of pulmonary rehabilitation in exercise capacity and quality of life in chronic obstructive pulmonary disease patients with and without global fat-free mass depletion.

PubMed

Berton, Danilo C; Silveira, Leonardo; Da Costa, Cassia C; De Souza, Rafael Machado; Winter, Claudia D; Zimermann Teixeira, Paulo José

2013-08-01

To investigate the effectiveness of pulmonary rehabilitation (PR) in exercise capacity and quality of life in patients with chronic obstructive pulmonary disease (COPD) with and without global fat-free mass (FFM) depletion. Retrospective case-control. Outpatient clinic, university center. COPD patients (N=102) that completed PR were initially evaluated. PR including whole-body and weight training for 12 weeks, 3 times per week. St. George Respiratory Questionnaire (SGRQ), 6-minute walk distance (6MWD), and FFM evaluation applied before and after PR. Patients were stratified according to their FFM status measured by bioelectric impedance. They were considered depleted if the FFM index was ≤ 15 kg/m(2) in women and ≤ 16 kg/m(2) in men. From the initial sample, all depleted patients (n=31) composed the FFM depleted group. It was composed predominantly by women (68%) with a mean age ± SD of 64.4 ± 7.3 years and a forced expiratory volume in 1 second of 33.6%=-13.2% predicted. Paired for sex and age, 31 nondepleted patients were selected from the initial sample to compose the nondepleted group. Improvement in the 6MWD was similar in these 2 groups after PR. Both groups improved SGRQ scores, although the observed power was small and did not allow adequate comparison between depleted and nondepleted patients. There was no difference between groups in weight change, whereas FFM tended to be greater in depleted patients. This increase had no correlation with the 6MWD or the SGRQ. Benefits of PR to exercise capacity were similar comparing FFM depleted and nondepleted COPD patients. Although FFM change tended to be greater in depleted patients, this increase had no definite relation with clinical outcomes. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Stage of Motivational Readiness: Predictive Ability for Exercise Behavior.

ERIC Educational Resources Information Center

Young, Deborah Rohm; King, Abby C.; Sheehan, Mary; Stefanick, Marcia L.

2002-01-01

Investigated whether stage of motivational readiness for exercise predicted adherence to an exercise intervention. Adults randomized into a trial had the exercise goal of completing or adding at least 10 miles of weekly brisk walking or jogging. Baseline exercise motivational readiness was assessed. Adherence was determined from logs. Overall, 64…

Prediction of exercise in patients across various stages of bariatric surgery: a comparison of the merits of the theory of reasoned action versus the theory of planned behavior.

PubMed

Hunt, Hillary R; Gross, Alan M

2009-11-01

Obesity is a world-wide health concern approaching epidemic proportions. Successful long-term treatment involves a combination of bariatric surgery, diet, and exercise. Social cognitive models, such as the Theory of Reasoned Action (TRA) and the Theory of Planned Behavior (TPB), are among the most commonly tested theories utilized in the prediction of exercise. As exercise is not a completely volitional behavior, it is hypothesized that the TPB is a superior theoretical model for the prediction of exercise intentions and behavior. This study tested validity of the TPB in a sample of bariatric patients and further validated its improvement over the TRA in predicting exercise adherence at different operative stages. Results generally confirmed research hypotheses. Superiority of the TPB model was validated in this sample of bariatric patients, and Perceived Behavioral Control emerged as the single-best predictor of both exercise intentions and self-reported behavior. Finally, results suggested that both subjective norms and attitudes toward exercise played a larger role in the prediction of intention and behavior than previously reported.

Adaptive Capacity: An Evolutionary Neuroscience Model Linking Exercise, Cognition, and Brain Health.

PubMed

Raichlen, David A; Alexander, Gene E

2017-07-01

The field of cognitive neuroscience was transformed by the discovery that exercise induces neurogenesis in the adult brain, with the potential to improve brain health and stave off the effects of neurodegenerative disease. However, the basic mechanisms underlying exercise-brain connections are not well understood. We use an evolutionary neuroscience approach to develop the adaptive capacity model (ACM), detailing how and why physical activity improves brain function based on an energy-minimizing strategy. Building on studies showing a combined benefit of exercise and cognitive challenge to enhance neuroplasticity, our ACM addresses two fundamental questions: (i) what are the proximate and ultimate mechanisms underlying age-related brain atrophy, and (ii) how do lifestyle changes influence the trajectory of healthy and pathological aging? Copyright © 2017 Elsevier Ltd. All rights reserved.

Endurance training and detraining in mitochondrial myopathies due to single large-scale mtDNA deletions.

PubMed

Taivassalo, Tanja; Gardner, Julie L; Taylor, Robert W; Schaefer, Andrew M; Newman, Jane; Barron, Martin J; Haller, Ronald G; Turnbull, Douglass M

2006-12-01

At present there are limited therapeutic interventions for patients with mitochondrial myopathies. Exercise training has been suggested as an approach to improve physical capacity and quality of life but it is uncertain whether it offers a safe and effective treatment for patients with heteroplasmic mitochondrial DNA (mtDNA) mutations. The objectives of this study were to assess the effects of exercise training and detraining in eight patients with single, large-scale mtDNA deletions to determine: (i) the efficacy and safety of endurance training (14 weeks) in this patient population; (ii) to determine the effect of more prolonged (total of 28 weeks) exercise training upon muscle and cardiovascular function and (iii) to evaluate the effect of discontinued training (14 weeks) upon muscle and cardiovascular function. Our results show that: (i) 14 weeks of exercise training significantly improved tolerance of submaximal exercise and peak capacity for work, oxygen utilization and skeletal muscle oxygen extraction with no change in the level of deleted mtDNA; (ii) continued training for an additional 14 weeks maintained these beneficial adaptations; (iii) the cessation of training (detraining) resulted in loss of physiological adaptation to baseline capacity with no overall change in mutation load. Patients' self assessment of quality of life as measured by the SF-36 questionnaire improved with training and declined with detraining. Whilst our findings of beneficial effects of training on physiological outcome and quality of life without increases in the percentage of deleted mtDNA are encouraging, we did not observe changes in mtDNA copy number. Therefore there remains a need for longer term studies to confirm that endurance exercise is a safe and effective treatment for patients with mitochondrial myopathies. The effects of detraining clearly implicate physical inactivity as an important mechanism in reducing exercise capacity and quality of life in patients with mitochondrial myopathy.

Effects of N-acetylcysteine on isolated skeletal muscle contractile properties after an acute bout of aerobic exercise.

PubMed

Jannig, Paulo R; Alves, Christiano R R; Voltarelli, Vanessa A; Bozi, Luiz H M; Vieira, Janaina S; Brum, Patricia C; Bechara, Luiz R G

2017-12-15

The current study tested the hypotheses that 1) an acute bout of aerobic exercise impairs isolated skeletal muscle contractile properties and 2) N-acetylcysteine (a thiol antioxidant; NAC) administration can restore the impaired muscle contractility after exercise. At rest or immediately after an acute bout of aerobic exercise, extensor digitorum longus (EDL) and soleus muscles from male Wistar rats were harvested for ex vivo skeletal muscle contraction experiments. Muscles from exercised animals were incubated in Krebs Ringer's buffer in absence or presence of 20mM of NAC. Force capacity and fatigue properties were evaluated. Exercised EDL and soleus displayed lower force production across various stimulation frequencies (p<0.001), indicating that skeletal muscle force production was impaired after an acute bout of exercise. However, NAC treatment restored the loss of force production in both EDL and soleus after fatiguing exercise (p<0.05). Additionally, NAC treatment increased relative force production at different time points during a fatigue-induced protocol, suggesting that NAC treatment mitigates fatigue induced by successive contractions. NAC treatment improves force capacity and fatigue properties in ex vivo skeletal muscle from rats submitted to an acute bout of aerobic exercise. Copyright © 2017 Elsevier Inc. All rights reserved.

Biologic Influences on Exercise Adherence.

ERIC Educational Resources Information Center

Dishman, Rod K.

1981-01-01

Diagnostic profiles of 362 male participants in an exercise program were analyzed to determine the biological variables between exercise adherence and symptoms of coronary disease. Findings indicated that individuals with lower metabolic capacity tended to adhere longer, to be less fit, were leaner, and began with more symptoms related to coronary…

Efficacy of isokinetic exercise on functional capacity and pain in patellofemoral pain syndrome.

PubMed

Alaca, Ridvan; Yilmaz, Bilge; Goktepe, A Salim; Mohur, Haydar; Kalyon, Tunc Alp

2002-11-01

To assess the effect of an isokinetic exercise program on symptoms and functions of patients with patellofemoral pain syndrome. A total of 22 consecutive patients with the complaint of anterior knee pain who met the inclusion criteria were recruited to assess the efficacy of isokinetic exercise on functional capacity, isokinetic parameters, and pain scores in patients with patellofemoral pain syndrome. A total of 37 knees were examined. Six-meter hopping, three-step hopping, and single-limb hopping course tests were performed for each patient with the measurements of the Lysholm scale and visual analog scale. Tested parameters were peak torque, total work, average power, and endurance ratios. Statistical analyses revealed that at the end of the 6-wk treatment period, functional and isokinetic parameters improved significantly, as did pain scores. There was not statistically significant correlation between different groups of parameters. The isokinetic exercise treatment program used in this study prevented the extensor power loss due to patellofemoral pain syndrome, but the improvement in the functional capacity was not correlated with the gained power.

Arterial oxygen content is precisely maintained by graded erythrocytotic responses in settings of high/normal serum iron levels, and predicts exercise capacity: an observational study of hypoxaemic patients with pulmonary arteriovenous malformations.

PubMed

Santhirapala, Vatshalan; Williams, Louisa C; Tighe, Hannah C; Jackson, James E; Shovlin, Claire L

2014-01-01

Oxygen, haemoglobin and cardiac output are integrated components of oxygen transport: each gram of haemoglobin transports 1.34 mls of oxygen in the blood. Low arterial partial pressure of oxygen (PaO2), and haemoglobin saturation (SaO2), are the indices used in clinical assessments, and usually result from low inspired oxygen concentrations, or alveolar/airways disease. Our objective was to examine low blood oxygen/haemoglobin relationships in chronically compensated states without concurrent hypoxic pulmonary vasoreactivity. 165 consecutive unselected patients with pulmonary arteriovenous malformations were studied, in 98 cases, pre/post embolisation treatment. 159 (96%) had hereditary haemorrhagic telangiectasia. Arterial oxygen content was calculated by SaO2 x haemoglobin x 1.34/100. There was wide variation in SaO2 on air (78.5-99, median 95)% but due to secondary erythrocytosis and resultant polycythaemia, SaO2 explained only 0.1% of the variance in arterial oxygen content per unit blood volume. Secondary erythrocytosis was achievable with low iron stores, but only if serum iron was high-normal: Low serum iron levels were associated with reduced haemoglobin per erythrocyte, and overall arterial oxygen content was lower in iron deficient patients (median 16.0 [IQR 14.9, 17.4]mls/dL compared to 18.8 [IQR 17.4, 20.1]mls/dL, p<0.0001). Exercise tolerance appeared unrelated to SaO2 but was significantly worse in patients with lower oxygen content (p<0.0001). A pre-defined athletic group had higher Hb:SaO2 and serum iron:ferritin ratios than non-athletes with normal exercise capacity. PAVM embolisation increased SaO2, but arterial oxygen content was precisely restored by a subsequent fall in haemoglobin: 86 (87.8%) patients reported no change in exercise tolerance at post-embolisation follow-up. Haemoglobin and oxygen measurements in isolation do not indicate the more physiologically relevant oxygen content per unit blood volume. This can be maintained for SaO2 ≥78.5%, and resets to the same arterial oxygen content after correction of hypoxaemia. Serum iron concentrations, not ferritin, seem to predict more successful polycythaemic responses.

Arterial Oxygen Content Is Precisely Maintained by Graded Erythrocytotic Responses in Settings of High/Normal Serum Iron Levels, and Predicts Exercise Capacity: An Observational Study of Hypoxaemic Patients with Pulmonary Arteriovenous Malformations

PubMed Central

Santhirapala, Vatshalan; Williams, Louisa C.; Tighe, Hannah C.; Jackson, James E.; Shovlin, Claire L.

2014-01-01

Background Oxygen, haemoglobin and cardiac output are integrated components of oxygen transport: each gram of haemoglobin transports 1.34 mls of oxygen in the blood. Low arterial partial pressure of oxygen (PaO2), and haemoglobin saturation (SaO2), are the indices used in clinical assessments, and usually result from low inspired oxygen concentrations, or alveolar/airways disease. Our objective was to examine low blood oxygen/haemoglobin relationships in chronically compensated states without concurrent hypoxic pulmonary vasoreactivity. Methodology 165 consecutive unselected patients with pulmonary arteriovenous malformations were studied, in 98 cases, pre/post embolisation treatment. 159 (96%) had hereditary haemorrhagic telangiectasia. Arterial oxygen content was calculated by SaO2 x haemoglobin x 1.34/100. Principal Findings There was wide variation in SaO2 on air (78.5–99, median 95)% but due to secondary erythrocytosis and resultant polycythaemia, SaO2 explained only 0.1% of the variance in arterial oxygen content per unit blood volume. Secondary erythrocytosis was achievable with low iron stores, but only if serum iron was high-normal: Low serum iron levels were associated with reduced haemoglobin per erythrocyte, and overall arterial oxygen content was lower in iron deficient patients (median 16.0 [IQR 14.9, 17.4]mls/dL compared to 18.8 [IQR 17.4, 20.1]mls/dL, p<0.0001). Exercise tolerance appeared unrelated to SaO2 but was significantly worse in patients with lower oxygen content (p<0.0001). A pre-defined athletic group had higher Hb:SaO2 and serum iron:ferritin ratios than non-athletes with normal exercise capacity. PAVM embolisation increased SaO2, but arterial oxygen content was precisely restored by a subsequent fall in haemoglobin: 86 (87.8%) patients reported no change in exercise tolerance at post-embolisation follow-up. Significance Haemoglobin and oxygen measurements in isolation do not indicate the more physiologically relevant oxygen content per unit blood volume. This can be maintained for SaO2 ≥78.5%, and resets to the same arterial oxygen content after correction of hypoxaemia. Serum iron concentrations, not ferritin, seem to predict more successful polycythaemic responses. PMID:24637882

Intestinal adaptations to a combination of different diets with and without endurance exercise.

PubMed

Daniels, Janice L; Bloomer, Richard J; van der Merwe, Marie; Davis, Samantha L; Buddington, Karyl K; Buddington, Randal K

2016-01-01

Endurance athletes search for diet regimens that will improve performance and decrease gastrointestinal disturbances during training and events. Although the intestine can adapt to changes in the amount and composition of dietary inputs, the responses to the combination of endurance exercise and diet are poorly understood. We evaluated small intestinal dimensions and mucosal architecture and calculated the capacities of the entire small intestine to digest maltose and maltodextrin and absorb glucose in response to two different diet types; a western human diet and the Daniel Fast, a vegan style diet, and with moderate intensity endurance training or a no-exercise sedentary lifestyle for a 13 week period (n = 7 per group). The influences of diet and exercise, alone and in combination, were analyzed by analysis of variation. Rats fed the western diet gained more weight (P < 0.05) due to more fat mass (P < 0.05), with a similar response for the sedentary compared with the exercised rats in each diet group (P < 0.05). The Daniel Fast rats had longer and heavier intestines with deeper crypts with villi that were wider (P < 0.05), but not taller. Despite increased energetic demands, the exercised rats had shorter and lighter intestines with shorter villi (P < 0.05). Yet, the percentage of mucosa did not differ among groups. Total small intestinal activities for maltase and α-glucoamylase, and capacities for glucose absorption were similar regardless of diet or exercise. These findings indicate the structural responses of the small intestine to a vegan style diet are modified by exercise, but without altering the capacities of the brush border membrane to digest and absorb carbohydrates.

High Oxygen Delivery to Preserve Exercise Capacity in Patients with Idiopathic Pulmonary Fibrosis Treated with Nintedanib. Methodology of the HOPE-IPF Study.

PubMed

Ryerson, Christopher J; Camp, Pat G; Eves, Neil D; Schaeffer, Michele; Syed, Nafeez; Dhillon, Satvir; Jensen, Dennis; Maltais, Francois; O'Donnell, Denis E; Raghavan, Natya; Roman, Michael; Stickland, Michael K; Assayag, Deborah; Bourbeau, Jean; Dion, Genevieve; Fell, Charlene D; Hambly, Nathan; Johannson, Kerri A; Kalluri, Meena; Khalil, Nasreen; Kolb, Martin; Manganas, Helene; Morán-Mendoza, Onofre; Provencher, Steve; Ramesh, Warren; Rolf, J Douglass; Wilcox, Pearce G; Guenette, Jordan A

2016-09-01

Pulmonary rehabilitation improves dyspnea and exercise capacity in idiopathic pulmonary fibrosis (IPF); however, it is unknown whether breathing high amounts of oxygen during exercise training leads to further benefits. Herein, we describe the design of the High Oxygen Delivery to Preserve Exercise Capacity in IPF Patients Treated with Nintedanib study (the HOPE-IPF study). The primary objective of this study is to determine the physiological and perceptual impact of breathing high levels of oxygen during exercise training in patients with IPF who are receiving antifibrotic therapy. HOPE-IPF is a two-arm double-blind multicenter randomized placebo-controlled trial of 88 patients with IPF treated with nintedanib. Patients will undergo 8 weeks of three times weekly aerobic cycle exercise training, breathing a hyperoxic gas mixture with a constant fraction of 60% inhaled oxygen, or breathing up to 40% oxygen as required to maintain an oxygen saturation level of at least 88%. End points will be assessed at baseline, postintervention (Week 8), and follow-up (Week 26). The primary analysis will compare the between-group baseline with post-training change in endurance time during constant work rate cycle exercise tests. Additional analyses will evaluate the impact of training with high oxygen delivery on 6-minute walk distance, dyspnea, physical activity, and quality of life. The HOPE-IPF study will lead to a comprehensive understanding of IPF exercise physiology, with the potential to change clinical practice by indicating the need for increased delivery of supplemental oxygen during pulmonary rehabilitation in patients with IPF. Clinical trial registered with www.clinicaltrials.gov (NCT02551068).

[Rehabilitation in COPD].

PubMed

Villiger, B

1999-03-01

Pulmonary rehabilitation (PR) is an important tool in the treatment of COPD patients. It is now clearly established that PR improves exercise capacity, reduces symptoms and improves quality of life in COPD patients. There is further evidence that the programmes also improve survival and reduce medical consumption. Pulmonary rehabilitation programmes are multidisziplinary and consist of exercise training (endurance, power), chest physiotherapie, education, psychosocial and nutritional support. Patients with poor exercise capacity, peripheral muscle weakness, severe complaints and poor quality of life seem to profit most from in- and outpatients rehab programmes. The type of rehabilitation depends on the severity of symptoms, the competence of the rehab-team and the local possibilities.

Combined Dietary Nitrate and Exercise Intervention in Peripheral Artery Disease: Protocol Rationale and Design

PubMed Central

Woessner, Mary N; VanBruggen, Mitch D; Pieper, Carl F; O'Reilly, Erin K; Kraus, William E

2017-01-01

Background Peripheral artery disease (PAD) is caused by atherosclerotic occlusions in the legs. It affects approximately 8-12 million people in the United States alone, one-third of whom suffer from intermittent claudication (IC), defined as ischemic leg pain that occurs with walking and improves with rest. Patients with IC suffer a markedly impaired quality of life and a high perception of disability. Improving pain-free walking time is a primary goal of rehabilitation in this population. Objective The nitric oxide (NO)-PAD trial is designed to compare the effects that 12 weeks of supervised exercise training, in combination with a high inorganic nitrate-content (beetroot [BR] juice) beverage or placebo (PL) beverage, has on clinical outcomes of exercise and functional capacity in two groups of PAD+IC patients: exercise training plus beetroot (EX+BR) and exercise training plus placebo (EX+PL). The primary aims of this randomized controlled, double-blind pilot study are to determine group differences following 12 weeks of EX+BR versus EX+PL in the changes for (1) exercise capacity: pain-free walking time (claudication onset time, COT), peak walk time (PWT), and maximal exercise capacity (peak oxygen uptake, VO2peak) during a maximal-graded cardiopulmonary exercise test (max CPX) and (2) functional capacity: 6-minute walk (6MW) distance. The secondary aims will provide mechanistic insights into the exercise outcome measures and will include (1) gastrocnemius muscle oxygenation during exercise via near-infrared spectroscopy (NIRS); (2) gastrocnemius muscle angiogenesis: capillaries per unit area and per muscle fiber, and relative fraction of type I, IIa, IIb, and IId/x fibers; and (3) vascular health/function via brachial artery flow-mediated dilation, lower-limb blood flow via plethysmography, and pulse wave velocity and reflection. Methods A total of 30 subjects between 40 and 80 years of age with PAD who are limited by IC will undergo exercise training 3 days per week for 12 weeks (ie, 36 sessions). They will be randomized to either the EX+BR or EX+PL group where participants will consume a beverage high in inorganic nitrate (4.2 mmol) or a low-nitrate placebo, respectively, 3 hours prior to each training session. Results Data collection from this study has been completed and is in the process of analysis and write-up. While the study is too underpowered—EX+BR, n=11; EX+PL, n=13—to determine between-group differences in the primary outcomes of COT, PWT, and 6MW, preliminary observations are promising with Cohen d effect sizes of medium to large. Conclusions Exercise training is currently the most effective therapy to increase functional capacity in PAD+IC. If the addition of inorganic nitrate to an exercise regimen elicits greater benefits, it may redefine the current standard of care for PAD+IC. Trial Registration ClinicalTrials.gov NCT01684930; https://clinicaltrials.gov/ct2/show/NCT01684930 (Archived by WebCite at http://www.webcitation.org/6raXFyEcP) PMID:28974486

Exercise improves mitochondrial and redox-regulated stress responses in the elderly: better late than never!

PubMed

Cobley, James N; Moult, Peter R; Burniston, Jatin G; Morton, James P; Close, Graeme L

2015-04-01

Ageing is associated with several physiological declines to both the cardiovascular (e.g. reduced aerobic capacity) and musculoskeletal system (muscle function and mass). Ageing may also impair the adaptive response of skeletal muscle mitochondria and redox-regulated stress responses to an acute exercise bout, at least in mice and rodents. This is a functionally important phenomenon, since (1) aberrant mitochondrial and redox homeostasis are implicated in the pathophysiology of musculoskeletal ageing and (2) the response to repeated exercise bouts promotes exercise adaptations and some of these adaptations (e.g. improved aerobic capacity and exercise-induced mitochondrial remodelling) offset age-related physiological decline. Exercise-induced mitochondrial remodelling is mediated by upstream signalling events that converge on downstream transcriptional co-factors and factors that orchestrate a co-ordinated nuclear and mitochondrial transcriptional response associated with mitochondrial remodelling. Recent translational human investigations have demonstrated similar exercise-induced mitochondrial signalling responses in older compared with younger skeletal muscle, regardless of training status. This is consistent with data indicating normative mitochondrial remodelling responses to long-term exercise training in the elderly. Thus, human ageing is not accompanied by diminished mitochondrial plasticity to acute and chronic exercise stimuli, at least for the signalling pathways measured to date. Exercise-induced increases in reactive oxygen and nitrogen species promote an acute redox-regulated stress response that manifests as increased heat shock protein and antioxidant enzyme content. In accordance with previous reports in rodents and mice, it appears that sedentary ageing is associated with a severely attenuated exercise-induced redox stress response that might be related to an absent redox signal. In this regard, regular exercise training affords some protection but does not completely override age-related defects. Despite some failed redox-regulated stress responses, it seems mitochondrial responses to exercise training are intact in skeletal muscle with age and this might underpin the protective effect of exercise training on age-related musculoskeletal decline. Whilst further investigation is required, recent data suggest that it is never too late to begin exercise training and that lifelong training provides protection against several age-related declines at both the molecular (e.g. reduced mitochondrial function) and whole-body level (e.g. aerobic capacity).

Exercise and Inflammatory Bowel Disease: Insights into Etiopathogenesis and Modification of Clinical Course.

PubMed

Hashash, Jana G; Binion, David G

2017-12-01

There is sparse information regarding exercise and inflammatory bowel disease (IBD). Furthermore, the importance of regular exercise in the optimal management of IBD has not received attention in guidelines and is often overlooked by practitioners. This article summarizes evidence regarding health benefits of exercise, guidelines regarding exercise in the general population and chronic inflammatory disorder populations, limitations regarding exercise capacity in patients with IBD, the association of lack of exercise with IBD pathogenesis, the role of exercise in beneficially modulating IBD clinical course, and extraintestinal benefits of exercise in patients with IBD. Copyright © 2017 Elsevier Inc. All rights reserved.

Interrelations among the adipocytokines leptin and adiponectin, oxidative stress and aseptic inflammation markers in pre- and early-pubertal normal-weight and obese boys.

PubMed

Paltoglou, George; Schoina, Maria; Valsamakis, George; Salakos, Nicolaos; Avloniti, Alexandra; Chatzinikolaou, Athanasios; Margeli, Alexandra; Skevaki, Chrysanthi; Papagianni, Maria; Kanaka-Gantenbein, Christina; Papassotiriou, Ioannis; Chrousos, George P; Fatouros, Ioannis G; Mastorakos, George

2017-03-01

Presumed interrelationships among deleterious aspects of adipose tissue metabolism, inflammation, and cellular oxidative stress could be influenced by pubertal hormonal changes. They were investigated in pre- and early pubertal normal-weight and obese boys before and after an exercise bout employed as an energy demanding stimulator. Cross-sectional study. Seventy-six healthy pre- (mean ± SD, 10.6 ± 0.2 years old, 28 normal-weight, and 11 obese) and early-(11.4 ± 0.2 years old, 25 normal-weight, and 12 obese) pubertal boys, were blood-sampled before and after a bout of exercise at 70% VO 2 max. Leptin, adiponectin, markers of inflammation (high-sensitivity C-reactive protein, high sensitivity IL-6), pro- (thiobarbitouric acid reactive substances, protein carbonyls) and anti- (glutathione, oxidized glutathione, glutathione peroxidase, catalase, total antioxidant capacity) oxidation were measured. Baseline and post-exercise adiponectin was greater and leptin and high-sensitivity C-reactive protein were lower in normal-weight than in obese pre- and early pubertal boys, while high sensitivity IL-6 was greater in obese than in normal-weight pre-pubertal boys. In pre-pubertal obese boys: at baseline, high-sensitivity C-reactive protein correlated negatively with catalase; high sensitivity IL-6 correlated positively with protein carbonyls; Δ (difference during exercise) adiponectin correlated positively with Δcatalase. In all boys: at baseline, high sensitivity IL-6 correlated positively with leptin and was the best negative and the second best positive predictor for post-exercise glutathione/oxidized glutathione and protein carbonyls, respectively; leptin was the best negative predictor for post-exercise glutathione; waist to height ratio was the best positive predictor for post-exercise thiobarbitouric acid reactive substances; body mass index z-score and adiponectin were, respectively, the best positive predictor for post-exercise protein carbonyls and catalase. In all subjects, leptin and adiponectin predict negatively and positively anti-oxidation, respectively, while high sensitivity IL-6 predicts positively and negatively pro- and anti-oxidation, respectively. High-sensitivity C-reactive protein is increased and negatively associated with anti-oxidation in pre-pubertal obese boys, suggesting that childhood obesity is associated with aseptic inflammation and oxidative stress.

Exercise Countermeasures Demonstration Project During the Lunar-Mars Life Support Test Project Phase 2A

NASA Technical Reports Server (NTRS)

Lee, Stuart M. C.; Guilliams, Mark E.; Moore, Alan D., Jr.; Williams, W. Jon; Greenisen, M. C.; Fortney, S. M.

1998-01-01

This demonstration project assessed the crew members' compliance to a portion of the exercise countermeasures planned for use onboard the International Space Station (ISS) and the outcomes of their performing these countermeasures. Although these countermeasures have been used separately in other projects and investigations, this was the first time they'd been used together for an extended period (60 days) in an investigation of this nature. Crew members exercised every day for six days, alternating every other day between aerobic and resistive exercise, and rested on the seventh day. On the aerobic exercise days, subjects exercised on an electronically braked cycle ergometer using a protocol that has been previously shown to maintain aerobic capacity in subjects exposed to a space flight analogue. On the resistive exercise days, crew members performed five major multijoint resistive exercises in a concentric mode, targeting those muscle groups and bones we believe are most severely affected by space flight. The subjects favorably tolerated both exercise protocols, with a 98% compliance to aerobic exercise prescription and a 91% adherence to the resistive exercise protocol. After 60 days, the crew members improved their peak aerobic capacity by an average 7%, and strength gains were noted in all subjects. These results suggest that these exercise protocols can be performed during ISS, lunar, and Mars missions, although we anticipate more frequent bouts with both protocols for long-duration spaceflight. Future projects should investigate the impact of increased exercise duration and frequency on subject compliance, and the efficacy of such exercise prescriptions.

Cardiopulmonary Exercise Testing in Adult Congenital Heart Disease.

PubMed

Mantegazza, Valentina; Apostolo, Anna; Hager, Alfred

2017-07-01

Recently, the number of patients with congenital heart diseases reaching adulthood has been progressively increasing in developed countries, and new issues are emerging: the evaluation of their capacity to cope with physical activity and whether this knowledge can be used to optimize medical management. A symptom-limited cardiopulmonary exercise test has proven to be an essential tool, because it can objectively evaluate the functional cardiovascular capacity of these patients, identify the pathological mechanisms of the defect (circulatory failure, shunts, and/or pulmonary hypertension), and help prescribe an individualized rehabilitation program when needed. The common findings on cardiopulmonary exercise testing in patients with congenital heart diseases are a reduced peak [Formula: see text]o 2 , an early anaerobic threshold, a blunted heart rate response, a reduced increase of Vt, and an increased [Formula: see text]e/[Formula: see text]co 2 . All these measures suggest common pathophysiological abnormalities: (1) a compromised exercise capacity from anomalies affecting the heart, vessels, lungs, or muscles; (2) chronotropic incompetence secondary to cardiac autonomic dysfunction or β-blockers and antiarrhythmic therapy; and (3) ventilatory inefficiency caused by left-heart failure with pulmonary congestion, pulmonary hypertension, pulmonary obstructive vascular disease, or cachexia. Most of these variables also have prognostic significance. For these patients, cardiopulmonary exercise testing allows evaluation and decisions affecting lifestyle and therapeutic interventions.

Circulating MicroRNAs as Potential Biomarkers of Exercise Response

PubMed Central

Polakovičová, Mája; Musil, Peter; Laczo, Eugen; Hamar, Dušan; Kyselovič, Ján

2016-01-01

Systematic physical activity increases physical fitness and exercise capacity that lead to the improvement of health status and athletic performance. Considerable effort is devoted to identifying new biomarkers capable of evaluating exercise performance capacity and progress in training, early detection of overtraining, and monitoring health-related adaptation changes. Recent advances in OMICS technologies have opened new opportunities in the detection of genetic, epigenetic and transcriptomic biomarkers. Very promising are mainly small non-coding microRNAs (miRNAs). miRNAs post-transcriptionally regulate gene expression by binding to mRNA and causing its degradation or inhibiting translation. A growing body of evidence suggests that miRNAs affect many processes and play a crucial role not only in cell differentiation, proliferation and apoptosis, but also affect extracellular matrix composition and maintaining processes of homeostasis. A number of studies have shown changes in distribution profiles of circulating miRNAs (c-miRNAs) associated with various diseases and disorders as well as in samples taken under physiological conditions such as pregnancy or physical exercise. This overview aims to summarize the current knowledge related to the response of blood c-miRNAs profiles to different modes of exercise and to highlight their potential application as a novel class of biomarkers of physical performance capacity and training adaptation. PMID:27782053

The effect of short-term intermittent hypoxic exposure on heart rate variability in a sedentary population.

PubMed

Lizamore, C A; Kathiravel, Y; Elliott, J; Hellemans, J; Hamlin, M J

2016-03-01

While the effects of instantaneous, single-bout exposure to hypoxia have been well researched, little is known about the autonomic response during, or as an adaptation to, repeated intermittent hypoxic exposure (IHE) in a sedentary population. Resting heart rate variability (HRV) and exercise capacity was assessed in 16 participants (8 receiving IHE, [Hyp] and 8 receiving a placebo treatment [C]) before and after a 4-week IHE intervention. Heart rate variability was also measured during an IHE session in the last week of the intervention. Post-intervention, the root mean squared successive difference (rMSSD) increased substantially in Hyp (71.6 ± 52.5%, mean change ± 90% confidence limits) compared to C suggesting an increase in vagal outflow. However, aside from a likely decrease in submaximal exercise heart rate in the Hyp group (-5.0 ± 6.4%) there was little evidence of improved exercise capacity. During the week 4 IHE measurement, HRV decreased during the hypoxic exposure (reduced R-R interval: -7.5 ± 3.2%; and rMSSD: -24.7 ± 17.3%) suggesting a decrease in the relative contribution of vagal activity. In summary, while 4 weeks of IHE is unlikely to improve maximal exercise capacity, it may be a useful means of increasing HRV in people unable to exercise.

Gender-related associations of genetic polymorphisms of α-adrenergic receptors, endothelial nitric oxide synthase and bradykinin B2 receptor with treadmill exercise test responses.

PubMed

Nunes, Rafael Amorim Belo; Barroso, Lúcia Pereira; Pereira, Alexandre da Costa; Krieger, José Eduardo; Mansur, Alfredo José

2014-01-01

Treadmill exercise test responses have been associated with cardiovascular prognosis in individuals without overt heart disease. Neurohumoral and nitric oxide responses may influence cardiovascular performance during exercise testing. Therefore, we evaluated associations between functional genetic polymorphisms of α-adrenergic receptors, endothelial nitric oxide synthase, bradykinin receptor B2 and treadmill exercise test responses in men and women without overt heart disease. We enrolled 766 (417 women; 349 men) individuals without established heart disease from a check-up programme at the Heart Institute, University of São Paulo Medical School. Exercise capacity, chronotropic reserve, maximum heart-rate achieved, heart-rate recovery, exercise systolic blood pressure (SBP), exercise diastolic blood pressure (DBP) and SBP recovery were assessed during exercise testing. Genotypes for the α-adrenergic receptors ADRA1A Arg347Cys (rs1048101), ADRA2A 1780 C>T (rs553668), ADRA2B Del 301-303 (rs28365031), endothelial nitric synthase (eNOS) 786 T>C (rs2070744), eNOS Glu298Asp (rs1799983) and BK2R (rs5810761) polymorphisms were assessed by PCR and high-resolution melting analysis. Maximum SBP was associated with ADRA1A rs1048101 (p=0.008) and BK2R rs5810761 (p=0.008) polymorphisms in men and ADRA2A rs553668 (p=0.008) and ADRA2B rs28365031 (p=0.022) in women. Maximum DBP pressure was associated with ADRA2A rs553668 (p=0.002) and eNOS rs1799983 (p=0.015) polymorphisms in women. Exercise capacity was associated with eNOS rs2070744 polymorphisms in women (p=0.01) and with eNOS rs1799983 in men and women (p=0.038 and p=0.024). The findings suggest that genetic variants of α-adrenergic receptors and bradykinin B2 receptor may be involved with blood pressure responses during exercise tests. Genetic variants of endothelial nitric oxide synthase may be involved with exercise capacity and blood pressure responses during exercise tests. These responses may be gender-related.

Gender-related associations of genetic polymorphisms of α-adrenergic receptors, endothelial nitric oxide synthase and bradykinin B2 receptor with treadmill exercise test responses

PubMed Central

Nunes, Rafael Amorim Belo; Barroso, Lúcia Pereira; Pereira, Alexandre da Costa; Krieger, José Eduardo; Mansur, Alfredo José

2014-01-01

Background Treadmill exercise test responses have been associated with cardiovascular prognosis in individuals without overt heart disease. Neurohumoral and nitric oxide responses may influence cardiovascular performance during exercise testing. Therefore, we evaluated associations between functional genetic polymorphisms of α-adrenergic receptors, endothelial nitric oxide synthase, bradykinin receptor B2 and treadmill exercise test responses in men and women without overt heart disease. Methods We enrolled 766 (417 women; 349 men) individuals without established heart disease from a check-up programme at the Heart Institute, University of São Paulo Medical School. Exercise capacity, chronotropic reserve, maximum heart-rate achieved, heart-rate recovery, exercise systolic blood pressure (SBP), exercise diastolic blood pressure (DBP) and SBP recovery were assessed during exercise testing. Genotypes for the α-adrenergic receptors ADRA1A Arg347Cys (rs1048101), ADRA2A 1780 C>T (rs553668), ADRA2B Del 301–303 (rs28365031), endothelial nitric synthase (eNOS) 786 T>C (rs2070744), eNOS Glu298Asp (rs1799983) and BK2R (rs5810761) polymorphisms were assessed by PCR and high-resolution melting analysis. Results Maximum SBP was associated with ADRA1A rs1048101 (p=0.008) and BK2R rs5810761 (p=0.008) polymorphisms in men and ADRA2A rs553668 (p=0.008) and ADRA2B rs28365031 (p=0.022) in women. Maximum DBP pressure was associated with ADRA2A rs553668 (p=0.002) and eNOS rs1799983 (p=0.015) polymorphisms in women. Exercise capacity was associated with eNOS rs2070744 polymorphisms in women (p=0.01) and with eNOS rs1799983 in men and women (p=0.038 and p=0.024). Conclusions The findings suggest that genetic variants of α-adrenergic receptors and bradykinin B2 receptor may be involved with blood pressure responses during exercise tests. Genetic variants of endothelial nitric oxide synthase may be involved with exercise capacity and blood pressure responses during exercise tests. These responses may be gender-related. PMID:25544888

The connection between chronic obstructive pulmonary disease symptoms and hyperinflation and its impact on exercise and function.

PubMed

Cooper, Christopher B

2006-10-01

Forced expiratory volume in 1 second (FEV1) has served as an important diagnostic measurement of chronic obstructive pulmonary disease (COPD) but has not been found to correlate with patient-centered outcomes such as exercise tolerance, dyspnea, or health-related quality of life. It has not helped us understand why some patients with severe FEV1 impairment have better exercise tolerance compared with others with similar FEV1 values. Hyperinflation, or air trapping caused by expiratory flow limitation, causes operational lung volumes to increase and even approach the total lung capacity (TLC) during exercise. Some study findings suggest that a dyspnea limit is reached when the end-inspiratory lung volume encroaches within approximately 500 mL of TLC. The resulting limitation in daily physical activity establishes a cycle of decline that includes physical deconditioning (elevated blood lactic acid levels at lower levels of exercise) and worsening dyspnea. Hyperinflation is reduced by long-acting bronchodilators that reduce airways resistance. The deflation of the lungs, in turn, results in an increased inspiratory capacity. For example, the once-daily anticholinergic bronchodilator tiotropium increases inspiratory capacity, 6-minute walk distance, and cycle exercise endurance time, and it decreases isotime fatigue or dyspnea. Pulmonary rehabilitation and oxygen therapy both reduce ventilatory requirements and improve breathing efficiency, thereby reducing hyperinflation and improving exertional dyspnea. Thus, hyperinflation is directly associated with patient-centered outcomes such as dyspnea and exercise limitation. Furthermore, therapeutic interventions--including pharmacotherapy and lung volume--reduction surgery--that reduce hyperinflation improve these outcomes.

Dietary nitrate does not reduce oxygen cost of exercise or improve muscle mitochondrial function in patients with mitochondrial myopathy.

PubMed

Nabben, Miranda; Schmitz, Joep P J; Ciapaite, Jolita; le Clercq, Carlijn M P; van Riel, Natal A; Haak, Harm R; Nicolay, Klaas; de Coo, Irenaeus F M; Smeets, Hubert; Praet, Stephan F; van Loon, Luc J; Prompers, Jeanine J

2017-05-01

Muscle weakness and exercise intolerance negatively affect the quality of life of patients with mitochondrial myopathy. Short-term dietary nitrate supplementation has been shown to improve exercise performance and reduce oxygen cost of exercise in healthy humans and trained athletes. We investigated whether 1 wk of dietary inorganic nitrate supplementation decreases the oxygen cost of exercise and improves mitochondrial function in patients with mitochondrial myopathy. Ten patients with mitochondrial myopathy (40 ± 5 yr, maximal whole body oxygen uptake = 21.2 ± 3.2 ml·min -1 ·kg body wt -1 , maximal work load = 122 ± 26 W) received 8.5 mg·kg body wt -1 ·day -1 inorganic nitrate (~7 mmol) for 8 days. Whole body oxygen consumption at 50% of the maximal work load, in vivo skeletal muscle oxidative capacity (evaluated from postexercise phosphocreatine recovery using 31 P-magnetic resonance spectroscopy), and ex vivo mitochondrial oxidative capacity in permeabilized skinned muscle fibers (measured with high-resolution respirometry) were determined before and after nitrate supplementation. Despite a sixfold increase in plasma nitrate levels, nitrate supplementation did not affect whole body oxygen cost during submaximal exercise. Additionally, no beneficial effects of nitrate were found on in vivo or ex vivo muscle mitochondrial oxidative capacity. This is the first time that the therapeutic potential of dietary nitrate for patients with mitochondrial myopathy was evaluated. We conclude that 1 wk of dietary nitrate supplementation does not reduce oxygen cost of exercise or improve mitochondrial function in the group of patients tested. Copyright © 2017 the American Physiological Society.

Combined activity of post-exercise concentrations of NA and eHsp72 on human neutrophil function: role of cAMP.

PubMed

Giraldo, Esther; Hinchado, María D; Ortega, Eduardo

2013-09-01

Extracellular heat shock proteins of 72 kDa (eHsp72) and noradrenaline (NA) can act as "danger signals" during exercise-induced stress by activating neutrophil function (chemotaxis, phagocytosis, and fungicidal capacity). In addition, post-exercise concentrations of NA increase the expression and release of Hsp72 by human neutrophils, and adrenoreceptors and cAMP are involved in the stimulation of neutrophils by eHsp72. This suggests an interaction between the two molecules in the modulation of neutrophils during exercise-induced stress. Given this context, the aim of the present investigation was to study the combined activity of post-exercise circulating concentrations of NA and eHsp72 on the neutrophil phagocytic process, and to evaluate the role of cAMP as intracellular signal in these effects. Results showed an accumulative stimulation of chemotaxis induced by NA and eHsp72. However, while NA and eHsp72, separately, stimulate the phagocytosis and fungicidal activity of neutrophils, when they act together they do not modify these capacities of neutrophils. Similarly, post-exercise concentrations of NA and eHsp72 separately increased the intracellular level of cAMP, but NA and eHsp72 acting together did not modify the intracellular concentration of cAMP. These results confirm that cAMP can be involved in the autocrine/paracrine physiological regulation of phagocytosis and fungicidal capacity of human neutrophils mediated by NA and eHsp72 in the context of exercise-induced stress. Copyright © 2013 Wiley Periodicals, Inc.

Dietary Nitrate Supplementation Improves Exercise Performance and Decreases Blood Pressure in COPD Patients

PubMed Central

Berry, Michael J.; Justus, Nicholas W.; Hauser, Jordan I.; Case, Ashlee H.; Helms, Christine C.; Basu, Swati; Rogers, Zachary; Lewis, Marc T.; Miller, Gary D.

2014-01-01

Dietary nitrate (NO3−) supplementation via beetroot juice has been shown to increase the exercise capacity of younger and older adults. The purpose of this study was to investigate the effects of acute NO3− ingestion on the submaximal constant work rate exercise capacity of COPD patients. Fifteen patients were assigned in a randomized, single-blind, crossover design to receive one of two treatments (beetroot juice then placebo or placebo then beetroot juice). Submaximal constant work rate exercise time at 75% of the patient’s maximal work capacity was the primary outcome. Secondary outcomes included plasma NO3− and nitrite (NO2−) levels, blood pressure, heart rate, oxygen consumption (VO2), dynamic hyperinflation, dyspnea and leg discomfort. Relative to placebo, beetroot ingestion increased plasma NO3− by 938% and NO2− by 379%. Median (+ interquartile range) exercise time was significantly longer (p = 0.031) following the ingestion of beetroot versus placebo (375.0 + 257.0 vs. 346.2 + 148.0 sec., respectively). Compared to placebo, beetroot ingestion significantly reduced iso-time (p = 0.001) and end exercise (p = 0.008) diastolic blood pressures by 6.4 and 5.6 mmHg, respectively. Resting systolic blood pressure was significantly reduced (p = 0.019) by 8.2 mmHg for the beetroot versus the placebo trial. No other variables were significantly different between the beetroot and placebo trials. These results indicate that acute dietary NO3− supplementation can elevate plasma NO3− and NO2− concentrations, improve exercise performance, and reduce blood pressure in COPD patients. PMID:25445634

Dietary nitrate supplementation improves exercise performance and decreases blood pressure in COPD patients.

PubMed

Berry, Michael J; Justus, Nicholas W; Hauser, Jordan I; Case, Ashlee H; Helms, Christine C; Basu, Swati; Rogers, Zachary; Lewis, Marc T; Miller, Gary D

2015-08-01

Dietary nitrate (NO3(-)) supplementation via beetroot juice has been shown to increase the exercise capacity of younger and older adults. The purpose of this study was to investigate the effects of acute NO3(-) ingestion on the submaximal constant work rate exercise capacity of COPD patients. Fifteen patients were assigned in a randomized, single-blind, crossover design to receive one of two treatments (beetroot juice then placebo or placebo then beetroot juice). Submaximal constant work rate exercise time at 75% of the patient's maximal work capacity was the primary outcome. Secondary outcomes included plasma NO3(-) and nitrite (NO2(-)) levels, blood pressure, heart rate, oxygen consumption (VO2), dynamic hyperinflation, dyspnea and leg discomfort. Relative to placebo, beetroot ingestion increased plasma NO3(-) by 938% and NO2(-) by 379%. Median (+interquartile range) exercise time was significantly longer (p = 0.031) following the ingestion of beetroot versus placebo (375.0 + 257.0 vs. 346.2 + 148.0 s, respectively). Compared with placebo, beetroot ingestion significantly reduced iso-time (p = 0.001) and end exercise (p = 0.008) diastolic blood pressures by 6.4 and 5.6 mmHg, respectively. Resting systolic blood pressure was significantly reduced (p = 0.019) by 8.2 mmHg for the beetroot versus the placebo trial. No other variables were significantly different between the beetroot and placebo trials. These results indicate that acute dietary NO3(-) supplementation can elevate plasma NO3(-) and NO2(-) concentrations, improve exercise performance, and reduce blood pressure in COPD patients. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of Combined Phase III and Phase II Cardiac Exercise Therapy for Middle-aged Male Patients with Acute Myocardial Infarction

PubMed Central

Lee, Chih-Wei; Wang, Ji-Hung; Hsieh, Jen-Che; Hsieh, Tsung-Cheng; Huang, Chien-Hui

2013-01-01

[Purpose] To investigate the effects of cardiac exercise therapy (CET) on exercise capacity and coronary risk factors (CRFs) of patients with acute myocardial infarction (AMI). [Methods] Patients who participated in an 8-week supervised, hospital-based phase II and 6-month home-based phase III CET with monthly telephone and/or home visits were defined as the exercise group (EG) (n=20), while those who did not receive phase II or phase III CET were defined as the no-exercise group (NEG) (n=10). CRFs were evaluated pre- and post-phase II and eight months after discharge. One and two-way repeated measures ANOVA were used to perform intra- and inter-group comparisons. [Results] Thirty men with AMI aged 49.3 ± 8.3 years were studied. EG increased their exercise capacity (METs) (6.8 ± 1.6 vs.10.0 ± 1.9) after phase II CET and was able to maintain it at 8-month follow-up. Both groups had significantly fewer persons who kept on smoking compared to the first examination. High density lipoprotein cholesterol (HDL-C) increased from 38.1 ± 11.0 to 43.7 ± 8.7 mg/dl at follow-up in EG while no significant difference was noted in NEG. [Conclusion] After phase III CET subjects had maintained the therapeutic effects of smoking cessation, and increasing exercise capacity obtained in phase II CET. HDL-C in EG continued to improve during phase III CET. PMID:24396201

Association of physical performance and biochemical profile of mice with intrinsic endurance swimming.

PubMed

Huang, Wen-Ching; Hsu, Yi-Ju; Wei, Li; Chen, Ying-Ju; Huang, Chi-Chang

2016-01-01

We aimed to investigate the potential mediators and relationship affecting congenital exercise performance in an animal model with physical activity challenge from physiological and biochemical perspectives. A total of 75 male ICR mice (5 weeks old) were adapted for 1 week, then mice performed a non-loading and exhaustive swimming test and were assigned to 3 groups by exhaustive swimming time: low exercise capacity (LEC) (<3 hr), medium exercise capacity (MEC) (3-5 hr), and high exercise capacity (HEC) (>5 hr). After a 1-week rest, the 3 groups of mice performed an exhaustive swimming test with a 5% and 7.5% weight load and a forelimb grip-strength test, with a 1-week rest between tests. Blood samples were collected immediately after an acute exercise challenge and at the end of the experiment (resting status) to evaluate biochemical blood variables and their relation with physical performance. Physical activity, including exhaustive swimming and grip strength, was greater for HEC than other mice. The swimming performance and grip strength between groups were moderately correlated (r=0.443, p <0.05). Resting serum ammonium level was moderately correlated with endurance with a 7.5% weight load (r=-0.447, p <0.05) and with lactate level (r=0.598, p <0.05). The pulmonary morphology of the HEC group seemed to indicate benefits for aerobic exercise. Mice showed congenital exercise performance, which was significantly correlated with different physical challenges and biochemical variable values. This study may have implications for interference in intrinsic characteristics.

Examining the relationship between endogenous pain modulation capacity and endurance exercise performance.

PubMed

Flood, Andrew; Waddington, Gordon; Cathcart, Stuart

2017-01-01

The aim of the current study was to examine the relationship between pain modulatory capacity and endurance exercise performance. Twenty-seven recreationally active males between 18 and 35 years of age participated in the study. Pain modulation was assessed by examining the inhibitory effect of a noxious conditioning stimulus (cuff occlusion) on the perceived intensity of a second noxious stimulus (pressure pain threshold). Participants completed two, maximal voluntary contractions followed by a submaximal endurance time task. Both performance tasks involved an isometric contraction of the non-dominant leg. The main analysis uncovered a correlation between pain modulatory capacity and performance on the endurance time task (r = -.425, p = .027), such that those with elevated pain modulation produced longer endurance times. These findings are the first to demonstrate the relationship between pain modulation responses and endurance exercise performance.

Sarcopenia and age-related changes in body composition and functional capacity.

PubMed

Evans, W J; Campbell, W W

1993-02-01

Advancing adult age is associated with profound changes in body composition. One of the most prominent of these changes is sarcopenia, defined as the age-related loss in skeletal muscle mass, which results in decreased strength and aerobic capacity and thus functional capacity. Sarcopenia is also closely linked to age-related losses in bone mineral, basal metabolic rate and increased body fat content. Through physical exercise and training, especially resistance training, it may be possible to prevent sarcopenia and the remarkable array of associated abnormalities, such as type II diabetes, coronary artery disease, hypertension, osteoporosis and obesity. Using an exercise program of sufficient frequency, intensity and duration, it is quite possible to increase muscle strength and endurance at any age. There is no pharmacological intervention that holds a greater promise of improving health and promoting independence in the elderly than does exercise.

Treadmill training as an augmentation treatment for Alzheimer's disease: a pilot randomized controlled study.

PubMed

Arcoverde, Cynthia; Deslandes, Andrea; Moraes, Helena; Almeida, Cloyra; Araujo, Narahyana Bom de; Vasques, Paulo Eduardo; Silveira, Heitor; Laks, Jerson

2014-03-01

To assess the effect of aerobic exercise on the cognition and functional capacity in Alzheimer's disease (AD) patients. Elderly (n=20) with mild dementia (NINCDS-ADRDA/CDR1) were randomly assigned to an exercise group (EG) on a treadmill (30 minutes, twice a week and moderate intensity of 60% VO₂max) and control group (GC) 10 patients. The primary outcome measure was the cognitive function using Cambridge Cognitive Examination (CAMCOG). Specifics instruments were also applied to evaluate executive function, memory, attention and concentration, cognitive flexibility, inhibitory control and functional capacity. After 16 weeks, the EG showed improvement in cognition CAMCOG whereas the CG declined. Compared to the CG, the EG presented significant improvement on the functional capacity. The analysis of the effect size has shown a favorable response to the physical exercise in all dependent variables. Walking on treadmill may be recommended as an augmentation treatment for patients with AD.

Is the 6-minute walk test a reliable substitute for peak oxygen uptake in patients with dilated cardiomyopathy?

PubMed

Zugck, C; Krüger, C; Dürr, S; Gerber, S H; Haunstetter, A; Hornig, K; Kübler, W; Haass, M

2000-04-01

The 6-min walk test may serve as a more simple clinical tool to assess functional capacity in congestive heart failure than determination of peak oxygen uptake by cardiopulmonary exercise testing. The purpose of the study was to prospectively examine whether the distance ambulated during a 6-min walk test (i) correlates with peak oxygen uptake, (ii) allows peak oxygen uptake to be predicted, and (iii) provides prognostic information similar to peak oxygen uptake in patients with dilated cardiomyopathy and left ventricular ejection fraction < or = 35%. In 113 patients (age: 54+/-12 years, NYHA: 2.2+/-0.8) with dilated cardiomyopathy (left ventricular ejection fraction 19+/-7%) a 6-min walk test and cardiopulmonary exercise testing were performed. The 6-min walk test and peak oxygen uptake were closely correlated at the initial visit (r=0.68, n=113), as well as after 263+/-114 (r=0.71, n=28) and 381+/-170 days (r=0.74, n=14). During serial exercise testing the 6-min walk test allowed peak oxygen uptake to be reliably predicted (r=0.76 between calculated and real peak oxygen uptake). After 528+/-234 days, 42 patients were hospitalized due to worsening heart failure and/or died from cardiovascular causes. Compared to clinically stable patients, these 42 patients walked a shorter distance (423+/-104 vs 501+/-95 m, P<0.001) and had a lower peak oxygen uptake (12.7+/-4.0 vs 17.4 + 5.6 ml x min(-1) x kg(-1), P<0.001). By univariate analysis the 6-min walk test outperformed other prognostic parameters such as left ventricular ejection fraction, cardiac index and plasma norepinephrine concentration and conferred a prognostic power similar to peak oxygen uptake. This predictive value could be further improved in a multivariate model, by combining the 6-min walk test with independent variables, such as left ventricular ejection fraction or cardiac index. The 6-min walk test correlated with peak oxygen uptake when tested serially over the course of the disease. Although both tests define two distinct domains of functional capacity, the 6-min walk test provides prognostic information very similar to peak oxygen uptake in congestive heart failure patients with dilated cardiomyopathy.

Exercise and diet determinants of overweight women participating in an exercise and diet program: a prospective examination of the theory of planned behavior.

PubMed

Gardner, Rebecca Ellis; Hausenblas, Heather A

2005-01-01

The purpose of this study was to examine prospectively the ability of direct and belief-based measures of the theory of planned behavior (TPB) constructs to predict exercise and diet intention and behavior of overweight women. Participants were 117 overweight, community-dwelling women and university students enrolled in a 4-week exercise and diet program. Participants completed baseline measures of demographic characteristics and the TPB constructs. Their exercise and diet adherence were also recorded. We found that: (1) the direct measure of perceived behavioral control (PBC) predicted exercise intention, (2) the direct measures of instrumental attitude, subjective norm, and PBC predicted diet intention, and (3) none of the direct or belief-based measures of the TPB constructs predicted 4-week exercise or diet behavior. Furthermore, several beliefs were associated with the direct measures of attitude, subjective norm, PBC, and intention. Implications of these results for designing exercise and diet interventions with overweight women are discussed.

Substantive hemodynamic and thermal strain upon completing lower-limb hot-water immersion; comparisons with treadmill running.

PubMed

Thomas, Kate N; van Rij, André M; Lucas, Samuel J E; Gray, Andrew R; Cotter, James D

2016-01-01

Exercise induces arterial flow patterns that promote functional and structural adaptations, improving functional capacity and reducing cardiovascular risk. While heat is produced by exercise, local and whole-body passive heating have recently been shown to generate favorable flow profiles and associated vascular adaptations in the upper limb. Flow responses to acute heating in the lower limbs have not yet been assessed, or directly compared to exercise, and other cardiovascular effects of lower-limb heating have not been fully characterized. Lower-limb heating by hot-water immersion (30 min at 42°C, to the waist) was compared to matched-duration treadmill running (65-75% age-predicted heart rate maximum) in 10 healthy, young adult volunteers. Superficial femoral artery shear rate assessed immediately upon completion was increased to a greater extent following immersion (mean ± SD: immersion +252 ± 137% vs. exercise +155 ± 69%, interaction: p = 0.032), while superficial femoral artery flow-mediated dilation was unchanged in either intervention. Immersion increased heart rate to a lower peak than during exercise (immersion +38 ± 3 beats·min -1 vs. exercise +87 ± 3 beats·min -1 , interaction: p < 0.001), whereas only immersion reduced mean arterial pressure after exposure (-8 ± 3 mmHg, p = 0.012). Core temperature increased twice as much during immersion as exercise (+1.3 ± 0.4°C vs. +0.6 ± 0.4°C, p < 0.001). These data indicate that acute lower-limb hot-water immersion has potential to induce favorable shear stress patterns and cardiovascular responses within vessels prone to atherosclerosis. Whether repetition of lower-limb heating has long-term beneficial effects in such vasculature remains unexplored.

Social Cognitive Theory Predictors of Exercise Behavior in Endometrial Cancer Survivors

PubMed Central

Basen-Engquist, Karen; Carmack, Cindy L.; Li, Yisheng; Brown, Jubilee; Jhingran, Anuja; Hughes, Daniel C.; Perkins, Heidi Y.; Scruggs, Stacie; Harrison, Carol; Baum, George; Bodurka, Diane C.; Waters, Andrew

2014-01-01

Objective This study evaluated whether social cognitive theory (SCT) variables, as measured by questionnaire and ecological momentary assessment (EMA), predicted exercise in endometrial cancer survivors. Methods One hundred post-treatment endometrial cancer survivors received a 6-month home-based exercise intervention. EMAs were conducted using hand-held computers for 10- to 12-day periods every 2 months. Participants rated morning self-efficacy and positive and negative outcome expectations using the computer, recorded exercise information in real time and at night, and wore accelerometers. At the midpoint of each assessment period participants completed SCT questionnaires. Using linear mixed-effects models, we tested whether morning SCT variables predicted minutes of exercise that day (Question 1) and whether exercise minutes at time point Tj could be predicted by questionnaire measures of SCT variables from time point Tj-1 (Question 2). Results Morning self-efficacy significantly predicted that day’s exercise minutes (p<.0001). Morning positive outcome expectations was also associated with exercise minutes (p=0.0003), but the relationship was attenuated when self-efficacy was included in the model (p=0.4032). Morning negative outcome expectations was not associated with exercise minutes. Of the questionnaire measures of SCT variables, only exercise self-efficacy predicted exercise at the next time point (p=0.003). Conclusions The consistency of the relationship between self-efficacy and exercise minutes over short (same day) and longer (Tj to Tj-1) time periods provides support for a causal relationship. The strength of the relationship between morning self-efficacy and exercise minutes suggest that real-time interventions that target daily variation in self-efficacy may benefit endometrial cancer survivors’ exercise adherence. PMID:23437853

Exercise capacity is associated with endothelin-1 release during emotional excitement in coronary artery disease patients.

PubMed

Tulppo, Mikko P; Piira, Olli-Pekka; Hautala, Arto J; Kiviniemi, Antti M; Miettinen, Johanna A; Huikuri, Heikki V

2014-08-01

Endothelin-1 (ET-1), a potent vasoconstrictor, IL-6, and catecholamines are increased and heart rate variability [SD of normal to normal R-R intervals (SDNN)] decreased during emotional excitement, but individual responses vary. We tested the hypothesis that exercise capacity is associated with physiological responses caused by real-life emotional excitement. We measured the plasma levels of ET-1, IL-6, catecholamines, heart rate, and SDNN in enthusiastic male ice hockey spectators (n = 51; age, 59 ± 9 years) with stable coronary artery disease (CAD) at baseline and during the Finnish National Ice Hockey League's final play-off matches. Maximal exercise capacity (METs) by bicycle exercise test and left ventricular ejection fraction (LVEF) were measured on a separate day. ET-1 response from baseline to emotional excitement correlated with maximal METs (r = -0.30; P = 0.040). In a linear stepwise regression analysis age, body mass index (BMI), METs, LVEF, basal ET-1, and subjective experience of excitement were entered the model as independent variables to explain ET-1 response. This model explained 27% of ET-1 response (P = 0.003). Maximal METs were most strongly correlated with ET-1 response (β = -0.45; partial correlation r = -0.43; P = 0.002), followed by BMI (β = -0.31; partial correlation r = -0.31; P = 0.033) and LVEF (β = -0.30; partial correlation r = -0.33; P = 0.023). Exercise capacity may protect against further cardiovascular events in CAD patients, because it is associated with reduced ET-1 release during emotional excitement. Copyright © 2014 the American Physiological Society.

Disruption of BCAA metabolism in mice impairs exercise metabolism and endurance.

PubMed

She, Pengxiang; Zhou, Yingsheng; Zhang, Zhiyou; Griffin, Kathleen; Gowda, Kavitha; Lynch, Christopher J

2010-04-01

Exercise enhances branched-chain amino acid (BCAA) catabolism, and BCAA supplementation influences exercise metabolism. However, it remains controversial whether BCAA supplementation improves exercise endurance, and unknown whether the exercise endurance effect of BCAA supplementation requires catabolism of these amino acids. Therefore, we examined exercise capacity and intermediary metabolism in skeletal muscle of knockout (KO) mice of mitochondrial branched-chain aminotransferase (BCATm), which catalyzes the first step of BCAA catabolism. We found that BCATm KO mice were exercise intolerant with markedly decreased endurance to exhaustion. Their plasma lactate and lactate-to-pyruvate ratio in skeletal muscle during exercise and lactate release from hindlimb perfused with high concentrations of insulin and glucose were significantly higher in KO than wild-type (WT) mice. Plasma and muscle ammonia concentrations were also markedly higher in KO than WT mice during a brief bout of exercise. BCATm KO mice exhibited 43-79% declines in the muscle concentration of alanine, glutamine, aspartate, and glutamate at rest and during exercise. In response to exercise, the increments in muscle malate and alpha-ketoglutarate were greater in KO than WT mice. While muscle ATP concentration tended to be lower, muscle IMP concentration was sevenfold higher in KO compared with WT mice after a brief bout of exercise, suggesting elevated ammonia in KO is derived from the purine nucleotide cycle. These data suggest that disruption of BCAA transamination causes impaired malate/aspartate shuttle, thereby resulting in decreased alanine and glutamine formation, as well as increases in lactate-to-pyruvate ratio and ammonia in skeletal muscle. Thus BCAA metabolism may regulate exercise capacity in mice.

Increasing discomfort tolerance predicts incentive senitization of exercise reinforcement: Preliminary results from a randomized controlled intervention to increase the reinforcing value of exercise in overweight to obese adu

USDA-ARS?s Scientific Manuscript database

Objective: The reinforcing (motivating) value of exercise/physical activity (RRVex) predicts usual exercise behavior and meeting of physical activity guidelines. Recent cross-sectional evidence suggests, for the first time, that greater tolerance for the discomfort experienced during exercise is ass...

Prediction of Maximum Oxygen Uptake Using Both Exercise and Non-Exercise Data

ERIC Educational Resources Information Center

George, James D.; Paul, Samantha L.; Hyde, Annette; Bradshaw, Danielle I.; Vehrs, Pat R.; Hager, Ronald L.; Yanowitz, Frank G.

2009-01-01

This study sought to develop a regression model to predict maximal oxygen uptake (VO[subscript 2max]) based on submaximal treadmill exercise (EX) and non-exercise (N-EX) data involving 116 participants, ages 18-65 years. The EX data included the participants' self-selected treadmill speed (at a level grade) when exercise heart rate first reached…

Research on Physical Activity in the Elderly: Practical Implications for Program Planning.

ERIC Educational Resources Information Center

Myers, Anita M.; Gonda, Gail

1986-01-01

The authors critically examine the research on physical activity in the elderly to assess the elderly's capacity for exercise and the benefits accruing from exercise. Lower-intensity exercise programs attract a more representative group of senior participants and overcome many barriers. Implications for program planning and efforts are discussed.…

Acute changes in arterial stiffness following exercise in people with metabolic syndrome.

PubMed

Radhakrishnan, Jeyasundar; Swaminathan, Narasimman; Pereira, Natasha M; Henderson, Keiran; Brodie, David A

This study aims to examine the changes in arterial stiffness immediately following sub-maximal exercise in people with metabolic syndrome. Ninety-four adult participants (19-80 years) with metabolic syndrome gave written consent and were measured for arterial stiffness using a SphygmoCor (SCOR-PVx, Version 8.0, Atcor Medical Private Ltd, USA) immediately before and within 5-10min after an incremental shuttle walk test. The arterial stiffness measures used were pulse wave velocity (PWV), aortic pulse pressure (PP), augmentation pressure, augmentation index (AI), subendocardial viability ratio (SEVR) and ejection duration (ED). There was a significant increase (p<0.05) in most of the arterial stiffness variables following exercise. Exercise capacity had a strong inverse correlation with arterial stiffness and age (p<0.01). Age influences arterial stiffness. Exercise capacity is inversely related to arterial stiffness and age in people with metabolic syndrome. Exercise induced changes in arterial stiffness measured using pulse wave analysis is an important tool that provides further evidence in studying cardiovascular risk in metabolic syndrome. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Value of Exercise Stress Electrocardiography for Risk Stratification in Patients With Suspected or Known Coronary Artery Disease in the Era of Advanced Imaging Technologies

PubMed Central

Bourque, Jamieson M.; Beller, George A.

2015-01-01

Exercise stress electrocardiography (ExECG) is underutilized as the initial test modality in patients with interpretable electrocardiograms able to exercise. Although, stress myocardial imaging techniques provide valuable diagnostic and prognostic information, variables derived from ExECG can yield substantial data for risk stratification, either supplementary to imaging variables, or without concurrent imaging. In addition to exercise-induced ischemic ST depression, such markers as ST segment elevation in lead AVR, abnormal heart rate recovery post-exercise, failure to achieve target heart rate, and poor exercise capacity improve risk stratification of ExECG. For example, patients achieving ≥10 METS on ExECG have a very low prevalence of inducible ischemia and an excellent prognosis. In contrast, cardiac imaging techniques add diagnostic and prognostic value in higher risk populations (e.g. poor functional capacity, diabetes, chronic kidney disease). Optimal test selection for symptomatic patients with suspected coronary artery disease requires a patient-centered approach factoring in the risk/benefit ratio and cost-effectiveness. PMID:26563861

Small Airway Dysfunction and Abnormal Exercise Responses

PubMed Central

Petsonk, Edward L.; Stansbury, Robert C.; Beeckman-Wagner, Lu-Ann; Long, Joshua L.; Wang, Mei Lin

2016-01-01

Rationale Coal mine dust exposure can cause symptoms and loss of lung function from multiple mechanisms, but the roles of each disease process are not fully understood. Objectives We investigated the implications of small airway dysfunction for exercise physiology among a group of workers exposed to coal mine dust. Methods Twenty coal miners performed spirometry, first breathing air and then helium-oxygen, single-breath diffusing capacity, and computerized chest tomography, and then completed cardiopulmonary exercise testing. Measurements and Main Results Six participants meeting criteria for small airway dysfunction were compared with 14 coal miners who did not. At submaximal workload, miners with small airway dysfunction used a higher proportion of their maximum voluntary ventilation and had higher ventilatory equivalents for both O2 and CO2. Regression modeling indicated that inefficient ventilation was significantly related to small airway dysfunction but not to FEV1 or diffusing capacity. At the end of exercise, miners with small airway dysfunction had 27% lower O2 consumption. Conclusions Small airway abnormalities may be associated with important inefficiency of exercise ventilation. In dust-exposed individuals with only mild abnormalities on resting lung function tests or chest radiographs, cardiopulmonary exercise testing may be important in defining causes of exercise intolerance. PMID:27073987

Individual experiences following a 6-month exercise intervention: A qualitative study

PubMed Central

Kerkelä, Ellen Staveborg; Jonsson, Linus; Lindwall, Magnus; Strand, Jennifer

2015-01-01

Purpose Dropout is a common problem in various exercise interventions. The individual's experience is believed to greatly impact dropout, yet little is known about the individual experiences of taking part in exercise interventions. The aim of this study was to examine individuals’ experiences following a self-determination theory–based exercise intervention in order to gain understanding of how standardized interventions can be adjusted to fit individuals’ specific needs, capacities, and circumstances. Methods A qualitative approach with semi-structured interviews was conducted with eight informants (three male and five female) aged between 26 and 47 years, whom all had participated in a 6-month exercise intervention with individual coaching based on self-determination theory and motivational interviewing. The interviews were analyzed thematically with an inductive approach. Results Aspects that influenced the informants’ motivation and participation in the exercise intervention were linked to three themes: the frames of the intervention, measurable changes, and the individual's context. The themes present information about the process and to what extent the informants felt that the intervention was adapted to fit their lives and needs. Conclusions This study emphasizes the importance of individualizing exercise interventions to support individuals’ diverse capacities and psychological needs. PMID:26282865

Respiratory muscle function and exercise limitation in patients with chronic obstructive pulmonary disease: a review.

PubMed

Charususin, Noppawan; Dacha, Sauwaluk; Gosselink, Rik; Decramer, Marc; Von Leupoldt, Andreas; Reijnders, Thomas; Louvaris, Zafeiris; Langer, Daniel

2018-01-01

Respiratory muscle dysfunction is common and contributes to dyspnea and exercise limitation in patients with chronic obstructive pulmonary disease (COPD). Improving dynamic function of respiratory muscles during exercise might help to reduce symptoms and improve exercise capacity. Areas covered: The aims of this review are to 1) summarize physiological mechanisms linking respiratory muscle dysfunction to dyspnea and exercise limitation; 2) provide an overview of available therapeutic approaches to better maintain load-capacity balance of respiratory muscles during exercise; and 3) to summarize current knowledge on potential mechanisms explaining effects of interventions aimed at optimizing dynamic respiratory muscle function with a special focus on inspiratory muscle training. Expert commentary: Several mechanisms which are potentially linking improvements in dynamic respiratory muscle function to symptomatic and functional benefits have not been studied so far in COPD patients. Examples of underexplored areas include the study of neural processes related to the relief of acute dyspnea and the competition between respiratory and peripheral muscles for limited energy supplies during exercise. Novel methodologies are available to non-invasively study these mechanisms. Better insights into the consequences of dynamic respiratory muscle dysfunction will hopefully contribute to further refine and individualize therapeutic approaches in patients with COPD.

Pre-exercise β-hydroxy-β-methylbutyrate free-acid supplementation improves work capacity recovery: a randomized, double-blinded, placebo-controlled study.

PubMed

Correia, Ana Luiza Matias; de Lima, Filipe Dinato; Bottaro, Martim; Vieira, Amilton; da Fonseca, Andrew Correa; Lima, Ricardo M

2018-02-08

The purpose of this study was to investigate the effects of a single-dose of β-hydroxy-β-methylbutyrate free acid (HMB-FA) supplementation on muscle recovery after a high-intensity exercise bout. Twenty-three trained young males were randomly assigned to receive either a single-dose supplementation of 3g of HMB-FA (n = 12; age 22.8 ± 3.0 years) or placebo (PLA; n = 11; age 22.9 ± 3.1 years). A muscle damage protocol was applied 60 minutes after supplementation, and consisted of seven sets of 20 drop jumps from a 60-cm box with 2-min rest intervals between sets. Muscle swelling, countermovement jump (CMJ), maximal voluntary isometric torque (MVIT) and work capacity (WC) were measured before, immediately after, 24, 48 and 72 hours after the exercise protocol. Muscle swelling, CMJ and MVIT changed similarly in both groups after the exercise protocol (p < 0.001), but returned to pre-exercise levels after 24 hours in both groups. WC decreased similarly in both groups after the exercise protocol (p < 0.01). For HMB-FA, WC returned to pre-exercise level 24 hours after exercise protocol. However, on PLA, WC did not return to pre-exercise level even 72 hours after the exercise protocol. In summary, a single-dose of HMB-FA supplementation improved WC recovery after a high-intensity exercise bout. However, HMB-FA did not affect the time-course of muscle swelling, MVIT and CMJ recovery.

Effects of Exercise Rehab on Male Asthmatic Patients: Aerobic Verses Rebound Training

PubMed Central

Zolaktaf, Vahid; Ghasemi, Gholam A; Sadeghi, Morteza

2013-01-01

Background: There are some auspicious records on applying aerobic exercise for asthmatic patients. Recently, it is suggested that rebound exercise might even increase the gains. This study was designed to compare the effects of rebound therapy to aerobic training in male asthmatic patients. Methods: Sample included 37 male asthmatic patients (20-40 years) from the same respiratory clinic. After signing the informed consent, subjects volunteered to take part in control, rebound, or aerobic groups. There was no change in the routine medical treatment of patients. Supervised exercise programs continued for 8 weeks, consisting of two sessions of 45 to 60 minutes per week. Criteria measures were assessed pre- and post exercise program. Peak exercise capacity (VO2peak) was estimated by modified Bruce protocol, Forced vital capacity (FVC), Forced expiratory volume in 1 second (FEV1), and FEV1% were measured by spirometer. Data were analyzed by repeated measure analysis of variance (ANOVA). Results: Significant interactions were observed for all 4 criteria measures (P < 0.01), meaning that both the exercise programs were effective in improving FVC, FEV1, FEV1%, and VO2peak. Rebound exercise produced more improvement in FEV1, FEV1%, and VO2peak. Conclusions: Regular exercise strengthens the respiratory muscles and improves the cellular respiration. At the same time, it improves the muscular, respiratory, and cardio-vascular systems. Effects of rebound exercise seem to be promising. Findings suggest that rebound exercise is a useful complementary means for asthmatic male patients. PMID:23717762

Muscle glycogen depletion and subsequent replenishment affect anaerobic capacity of horses.

PubMed

Lacombe, V A; Hinchcliff, K W; Geor, R J; Baskin, C R

2001-10-01

The purpose of this study was to determine the effect of muscle glycogen depletion and subsequent replenishment on anaerobic capacity of horses. In a blinded crossover study, seven fit horses performed glycogen-depleting exercise on two occasions. Horses were infused after glycogen-depleting exercise with either 6 g/kg body wt of glucose as a 13.5% solution in 0.9% NaCl (Glu) or with 0.9% NaCl (Sal) of equivalent volume. Subsequently, horses performed a high-speed exercise test (120% of maximal rate of oxygen consumption) to estimate maximum accumulated oxygen deficit. Replenishment of muscle glycogen was greater (P < 0.05) in Glu [from 24.7 +/- 7.2 (SE) to 116.5 +/- 7 mmol/kg wet wt before and after infusion, respectively] than in Sal (from 23.4 +/- 7.2 to 47.8 +/- 5.7 mmol/kg wet wt before and after infusion, respectively). Run time to fatigue during the high-speed exercise test (97.3 +/- 8.2 and 70.8 +/- 8.3 s, P < 0.05), maximal accumulated oxygen deficit (105.7 +/- 9.3 and 82.4 +/- 10.3 ml O(2) equivalent/kg, P < 0.05), and blood lactate concentration at the end of the high-speed exercise test (11.1 +/- 1.4 and 9.2 +/- 3.7 mmol/l, P < 0.05) were greater for Glu than for Sal, respectively. We concluded that decreased availability of skeletal muscle glycogen stores diminishes anaerobic power generation and capacity for high-intensity exercise in horses.

Effect of HX108-CS supplementation on exercise capacity and lactate accumulation after high-intensity exercise

PubMed Central

2013-01-01

Background In the present study, we determined the effects of HX108-CS (mixed extract of Schisandra chinensis and Chaenomeles sinensis) supplementation on lactate accumulation and endurance capacity. Furthermore, we examined CK (creatine kinase), LDH (lactate dehydrogenase) activity to determine whether the HX108-CS affected markers of skeletal muscle injury in vivo and in vitro. Methods Exercise capacity was measured by an exhaustive swimming test using ICR mice divided into four groups; one group received distilled water (DW) (Control group, n = 10), and the other groups received three different dosages of HX108-CS (10, 50 and 100 mg/kg, n = 10 per group) solution in water orally. Then, for the time-dependent measurements of blood lactate, CK, and LDH, Sprague–Dawley rats were divided into two groups; one received DW (Control group, n = 10), and the other group received HX108-CS (100 mg/kg, n = 10) solution in the same way as mice. Before the exercise test, the animals were given either DW or HX108-CS for 2 weeks. High-intensity treadmill exercise was performed for 30 minutes. Blood samples were collected and analyzed during and after exercise. For the in vitro experiment, C2C12 cells were treated with HX108-CS to examine its effect on lactate production, CK, and LDH activity. Results Blood lactate concentration was significantly lowered immediately after treadmill exercise in HX108-CS group; however, there were no significant differences in activities of CK and LDH between HX108-CS and control during treadmill exercise and recovery phase. Furthermore, treatment with 100 mg/kg of HX108-CS led to a significant increase in the time to exhaustion in swimming test, and concurrently blood lactate concentration was significantly decreased in 50 and 100 mg/kg treated group. Moreover, our results of in vitro experiment showed that HX108-CS suppressed lactate production, CK, and LDH activity in a dose-dependent manner. Conclusions These results suggest that supplementation with HX108-CS may enhance exercise capacity by lowering lactate accumulation. This may in part be related to an amelioration of skeletal muscle injury. PMID:23587302

An in-depth, longitudinal examination of the daily physical activity of a patient with heart failure using a Nintendo Wii at home: a case report.

PubMed

Klompstra, Leonie Verheijden; Jaarsma, Tiny; Strömberg, Anna

2013-06-01

To explore the influence of the Nintendo Wii on the daily physical activity of a patient with chronic heart failure at home. A 74-year-old Swedish patient with heart failure had access to a Nintendo Wii at home for 12 weeks. Exercise motivation, exercise self-efficacy and exercise capacity were assessed before and after the intervention. Data on perceived physical effort, global well-being and expended energy were collected every day during the intervention. During the 12 weeks of access to the Nintendo Wii, daily physical activity increased by 200% on weekdays and 57% on weekends, compared with baseline. The patient's exercise motivation and exercise self-efficacy increased during the study, whereas perceived physical effort and global well-being did not change. The patient had no difficulties in using the system and did not suffer any major harm. The results of this case study suggest that providing patients with heart failure access to a Nintendo Wii is a promising and safe intervention. The energy expended by the patient per day increased, as did exercise capacity. Playing the Nintendo Wii did not increase the perceived physical effort, but increased motivation to exercise and decreased barriers to exercising.

Predictors of Obligatory Exercise among Undergraduates: Differential Implications for Counseling College Men and Women

ERIC Educational Resources Information Center

Chalk, Holly M.; Miller, Sarah E.; Roach, Megan E.; Schultheis, Kara S.

2013-01-01

This study examined predictors of obligatory exercise in college undergraduates ("N"= 172). Regression models indicated that internalization of Western attitudes toward appearance predicted exercise fixation and commitment in women, whereas perceived pressure from dating partners predicted exercise commitment in men. Findings suggest…

Six-minute walking test predicts maximal fat oxidation in obese children.

PubMed

Makni, E; Moalla, W; Trabelsi, Y; Lac, G; Brun, J F; Tabka, Z; Elloumi, M

2012-07-01

Obesity is associated with reduced exercise maximal fat oxidation rate (FATmax), which is generally assessed by cardiopulmonary cycling test. The six-minute walking test (6MWT) presents an alternative method in patients. The aim of this study was to establish a practical reference equation facilitating the prediction of FATmax from the 6 MWT in obese children of both genders. This study is a cross-sectional study using mixed linear and multiple regression models. Anthropometric measurements were recorded and submaximal cycling test and 6 MWT conducted for 131 school-aged obese children, 68 boys and 63 girls. A multiple regression analysis for FATmax, including six-minute walking distance (6 MWD), anthropometric and cardiac parameters as the dependent variables, was performed for the two genders separately. Mean 6 MWD and FATmax were 564.9 ± 53.7 m and 126.5 ± 12.1 mg min(-1) for boys and 506.7 ± 55.0 m and 120.7 ± 10.0 mg min(-1) for girls, respectively. The 6MWD, body mass index, Z-score, fat-free mass, waist and hip circumferences (WC and HC), rest heart rate, and systolic and diastolic blood pressures were highly correlated with FATmax for both genders. There was a significant correlation between 6 MWD and FATmax in both boys and girls (r = 0.88 and r = 0.81, P<0.001, respectively). Stepwise regression analyses revealed that the combinations of 6 MWD with HC for boys and 6MWD with WC for girls improved the predictability of the model (R(2) = 0.81 for boys and R(2) = 0.72 for girls; P<0.001). In obese children, the 6MWT can be used to predict FATmax when formal test of exercise capacity and gas exchange analysis are unavailable or impractical. It is therefore possible to prescript targeted exercises at FATmax, without performing indirect calorimetry, just from a field test.