Edman, Jeanne L; Lynch, Wesley C; Yates, Alayne
2014-01-01
Depression is a common psychological problem and females have been found to be at greater risk for this disorder than males. Although numerous studies have found that physical exercise is negatively associated with risk of depression, some studies suggest that negative exercise attitudes may increase the risk of depression. The present study used the survey method to examine the relationship between depressive symptoms, exercise performance dissatisfaction, body dissatisfaction, and physical exercise among a sample of 895 undergraduate university students. Females reported higher depression and exercise performance dissatisfaction scores than males; however, there were no gender differences in body dissatisfaction. Exercise performance dissatisfaction was positively associated with depression among both males and females. Physical exercise was negatively associated with depression among males, but not among females. The possibility of screening participants enrolled in exercise programs for performance dissatisfaction is discussed as negative exercise attitudes may diminish the positive impact of exercise on depressed mood.
Paluska, Scott A
2003-08-01
Caffeine is the most commonly consumed drug in the world, and athletes frequently use it as an ergogenic aid. It improves performance and endurance during prolonged, exhaustive exercise. To a lesser degree it also enhances short-term, high-intensity athletic performance. Caffeine improves concentration, reduces fatigue, and enhances alertness. Habitual intake does not diminish caffeine's ergogenic properties. Several mechanisms have been proposed to explain the physiologic effects of caffeine, but adenosine receptor antagonism most likely accounts for the primary mode of action. It is relatively safe and has no known negative performance effects, nor does it cause significant dehydration or electrolyte imbalance during exercise. Routine caffeine consumption may cause tolerance or dependence, and abrupt discontinuation produces irritability, mood shifts, headache, drowsiness, or fatigue. Major sport governing bodies ban excessive use of caffeine, but current monitoring techniques are inadequate, and ethical dilemmas persist regarding caffeine intake by athletes.
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.
Acute Exercise and Motor Memory Consolidation: The Role of Exercise Timing
Christiansen, Lasse; Roig, Marc
2016-01-01
High intensity aerobic exercise amplifies offline gains in procedural memory acquired during motor practice. This effect seems to be evident when exercise is placed immediately after acquisition, during the first stages of memory consolidation, but the importance of temporal proximity of the exercise bout used to stimulate improvements in procedural memory is unknown. The effects of three different temporal placements of high intensity exercise were investigated following visuomotor skill acquisition on the retention of motor memory in 48 young (24.0 ± 2.5 yrs), healthy male subjects randomly assigned to one of four groups either performing a high intensity (90% Maximal Power Output) exercise bout at 20 min (EX90), 1 h (EX90+1), 2 h (EX90+2) after acquisition or rested (CON). Retention tests were performed at 1 d (R1) and 7 d (R7). At R1 changes in performance scores after acquisition were greater for EX90 than CON (p < 0.001) and EX90+2 (p = 0.001). At R7 changes in performance scores for EX90, EX90+1, and EX90+2 were higher than CON (p < 0.001, p = 0.008, and p = 0.008, resp.). Changes for EX90 at R7 were greater than EX90+2 (p = 0.049). Exercise-induced improvements in procedural memory diminish as the temporal proximity of exercise from acquisition is increased. Timing of exercise following motor practice is important for motor memory consolidation. PMID:27446616
High-volume resistance training session acutely diminishes respiratory muscle strength.
Hackett, Daniel A; Johnson, Nathan A; Chow, Chin-Moi
2012-01-01
This study investigated the effect of a high-volume compared to a low-volume resistance training session on maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). Twenty male subjects with resistance training experience (6.2 ± 3.2 y), in a crossover trial, completed two resistance training protocols (high-volume: 5 sets per exercise; low-volume: 2 sets per exercise) and a control session (no exercise) on 3 separate occasions. MIP and MEP decreased by 13.6% (p < 0.01) and 14.7% (p < 0.01) respectively from pre-session MIP and MEP, following the high-volume session. MIP and MEP were unaffected following the low-volume or the control sessions. MIP returned to pre-session values after 40 minutes, whereas MEP remained significantly reduced after 60 minutes post-session by 9.2% compared to pre-session (p < 0.01). The findings suggest that the high-volume session significantly decreased MIP and MEP post-session, implicating a substantially increased demand on the respiratory muscles and that adequate recovery is mandatory following this mode of training. Key pointsRespiratory muscular strength performance is acutely diminished following a high-volume whole-body resistance training session.Greater ventilatory requirements and generation of IAP during the high-volume resistance training session may have contributed to the increased demand placed on the respiratory muscles.Protracted return of respiratory muscular strength performance to baseline levels may have implications for individuals prior to engaging in subsequent exercise bouts.
Ulrich, Silvia; Schneider, Simon R; Bloch, Konrad E
2017-12-01
Exercise performance is determined by oxygen supply to working muscles and vital organs. In healthy individuals, exercise performance is limited in the hypoxic environment at altitude, when oxygen delivery is diminished due to the reduced alveolar and arterial oxygen partial pressures. In patients with pulmonary hypertension (PH), exercise performance is already reduced near sea level due to impairments of the pulmonary circulation and gas exchange, and, presumably, these limitations are more pronounced at altitude. In studies performed near sea level in healthy subjects, as well as in patients with PH, maximal performance during progressive ramp exercise and endurance of submaximal constant-load exercise were substantially enhanced by breathing oxygen-enriched air. Both in healthy individuals and in PH patients, these improvements were mediated by a better arterial, muscular, and cerebral oxygenation, along with a reduced sympathetic excitation, as suggested by the reduced heart rate and alveolar ventilation at submaximal isoloads, and an improved pulmonary gas exchange efficiency, especially in patients with PH. In summary, in healthy individuals and in patients with PH, alterations in the inspiratory Po 2 by exposure to hypobaric hypoxia or normobaric hyperoxia reduce or enhance exercise performance, respectively, by modifying oxygen delivery to the muscles and the brain, by effects on cardiovascular and respiratory control, and by alterations in pulmonary gas exchange. The understanding of these physiological mechanisms helps in counselling individuals planning altitude or air travel and prescribing oxygen therapy to patients with PH.
Paschalis, Vassilis; Theodorou, Anastasios A.; Panayiotou, George; Kyparos, Antonios; Patikas, Dimitrios; Grivas, Gerasimos V.; Nikolaidis, Michalis G.; Vrabas, Ioannis S.
2013-01-01
A novel automatic escalator was designed, constructed and used in the present investigation. The aim of the present investigation was to compare the effect of two repeated sessions of stair descending versus stair ascending exercise on muscle performance and health-related parameters in young healthy men. Twenty males participated and were randomly divided into two equal-sized groups: a stair descending group (muscle-damaging group) and a stair ascending group (non-muscle-damaging group). Each group performed two sessions of stair descending or stair ascending exercise on the automatic escalator while a three week period was elapsed between the two exercise sessions. Indices of muscle function, insulin sensitivity, blood lipid profile and redox status were assessed before and immediately after, as well as at day 2 and day 4 after both exercise sessions. It was found that the first bout of stair descending exercise caused muscle damage, induced insulin resistance and oxidative stress as well as affected positively blood lipid profile. However, after the second bout of stair descending exercise the alterations in all parameters were diminished or abolished. On the other hand, the stair ascending exercise induced only minor effects on muscle function and health-related parameters after both exercise bouts. The results of the present investigation indicate that stair descending exercise seems to be a promising way of exercise that can provoke positive effects on blood lipid profile and antioxidant status. PMID:23437093
Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats.
Lalanza, Jaume F; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M
2015-11-05
Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders.
Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats
Lalanza, Jaume F.; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M.
2015-01-01
Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders. PMID:26538081
Sawka, Michael N; Leon, Lisa R; Montain, Scott J; Sonna, Larry A
2011-10-01
This article emphasizes significant recent advances regarding heat stress and its impact on exercise performance, adaptations, fluid electrolyte imbalances, and pathophysiology. During exercise-heat stress, the physiological burden of supporting high skin blood flow and high sweating rates can impose considerable cardiovascular strain and initiate a cascade of pathophysiological events leading to heat stroke. We examine the association between heat stress, particularly high skin temperature, on diminishing cardiovascular/aerobic reserves as well as increasing relative intensity and perceptual cues that degrade aerobic exercise performance. We discuss novel systemic (heat acclimation) and cellular (acquired thermal tolerance) adaptations that improve performance in hot and temperate environments and protect organs from heat stroke as well as other dissimilar stresses. We delineate how heat stroke evolves from gut underperfusion/ischemia causing endotoxin release or the release of mitochondrial DNA fragments in response to cell necrosis, to mediate a systemic inflammatory syndrome inducing coagulopathies, immune dysfunction, cytokine modulation, and multiorgan damage and failure. We discuss how an inflammatory response that induces simultaneous fever and/or prior exposure to a pathogen (e.g., viral infection) that deactivates molecular protective mechanisms interacts synergistically with the hyperthermia of exercise to perhaps explain heat stroke cases reported in low-risk populations performing routine activities. Importantly, we question the "traditional" notion that high core temperature is the critical mediator of exercise performance degradation and heat stroke. Published 2011. This article is a U.S. Government work and is in the public domain in the USA.
Easterling, Caryn
2008-09-01
Age-related sarcopenia or muscle wasting contributes to changes in the ability to perform activities of daily living, changes in deglutition, and changes in vocal function. The Shaker Exercise, an isometric and isokinetic exercise, has been shown to strengthen suprahyoid muscles and increase deglutitive anteroposterior (AP) upper esophageal sphincter (UES) opening diameter. The aim of this study was to determine if this exercise has an effect on the age-related changes in vocal function and deglutition in healthy older adults. Eleven females and 10 males, aged 65-78 years (mean = 70 +/- 4 years) and with a negative history for dysphagia and voice disorders, participated by exercising three times per day for 6 weeks. Five age-matched controls did not perform the exercise. Acoustic analysis of voice and biomechanical analysis of deglutition were performed before and after 6 weeks of exercise. Controls participated in voice analysis only. Dysphonia Severity Index (DSI), a multivariate voice index, was used to compare voice production initially and after 6 weeks. Deglutitive biomechanical measures increased and DSI scores improved in 10 of 21 participants following 6 weeks of the exercise. DSI for controls did not change over the 6-week period. Ten of 21 exercise participants experienced improved deglutitive biomechanics and DSI scores. Accuracy of exercise performance, compliance, and/or disclosed alterations in health status may contribute to the lack of deglutitive and DSI change in the participants who did not experience change in function. A large randomized control study, including periodic monitoring of health status, exercise performance accuracy, and compliance, is warranted to evaluate the affect of this exercise on deglutition as well as voice. The Shaker Exercise could be recommended as a preventative measure to diminish the effect of sarcopenia on the muscles used in deglutition and voice and alter the progression of the characteristic senescent voice and swallow changes.
Davis, Robert T.; Stabley, John N.; Dominguez, James M.; Ramsey, Michael W.; McCullough, Danielle J.; Lesniewski, Lisa A.; Delp, Michael D.
2013-01-01
Adipose tissue (AT), which typically comprises an increased percentage of body mass with advancing age, receives a large proportion of resting cardiac output. During exercise, an old age-associated inability to increase vascular resistance within the intra-abdominal AT may compromise the ability of the cardiovascular system to redistribute blood flow to the active musculature, contributing to the decline in exercise capacity observed in this population. We tested the hypotheses that 1) there would be an elevated perfusion of AT during exercise with old age that was associated with diminished vasoconstrictor responses of adipose-resistance arteries, and 2) chronic exercise training would mitigate the age-associated alterations in AT blood flow and vascular function. Young (6 mo; n = 40) and old (24 mo; n = 28) male Fischer 344 rats were divided into young sedentary (YSed), old sedentary (OSed), young exercise trained (YET), or old exercise trained (OET) groups, where training consisted of 10-12 wk of treadmill exercise. In vivo blood flow at rest and during exercise and in vitro α-adrenergic and myogenic vasoconstrictor responses in resistance arteries from AT were measured in all groups. In response to exercise, there was a directionally opposite change in AT blood flow in the OSed group (∼150% increase) and YSed (∼55% decrease) vs. resting values. Both α-adrenergic and myogenic vasoconstriction were diminished in OSed vs. YSed AT-resistance arteries. Exercise training resulted in a similar AT hyperemic response between age groups during exercise (YET, 9.9 ± 0.5 ml·min−1·100−1 g; OET, 8.1 ± 0.9 ml·min−1·100−1 g) and was associated with enhanced myogenic and α-adrenergic vasoconstriction of AT-resistance arteries from the OET group relative to OSed. These results indicate that there is an inability to increase vascular resistance in AT during exercise with old age, due, in part, to a diminished vasoconstriction of AT arteries. Furthermore, the results indicate that exercise training can augment vasoconstriction of AT arteries and mitigate age-related alterations in the regulation of AT blood flow during exercise. PMID:23349454
O'Byrne, Michael L; Desai, Sanyukta; Lane, Megan; McBride, Michael; Paridon, Stephen; Goldmuntz, Elizabeth
2017-03-01
Increasing habitual exercise has been associated with improved cardiopulmonary exercise testing (CPET) performance, specifically maximal oxygen consumption in children with operatively corrected congenital heart disease. This has not been studied in children following Fontan palliation, a population in whom CPET performance is dramatically diminished. A single-center cross-sectional study with prospective and retrospective data collection was performed that assessed habitual exercise preceding a clinically indicated CPET in children and adolescents with Fontan palliation, transposition of the great arteries following arterial switch operation (TGA), and normal cardiac anatomy without prior operation. Data from contemporaneous clinical reports and imaging studies were collected. The association between percent predicted VO 2max and habitual exercise duration adjusted for known covariates was tested. A total of 175 subjects (75 post-Fontan, 20 with TGA, and 80 with normal cardiac anatomy) were enrolled. VO 2max was lower in the Fontan group than patients with normal cardiac anatomy (p < 0.0001) or TGA (p < 0.0001). In Fontan subjects, both univariate and multivariate analysis failed to demonstrate a significant association between habitual exercise and VO 2max (p = 0.6), in sharp contrast to cardiac normal subjects. In multivariate analysis, increasing age was the only independent risk factor associated with decreasing VO 2max in the Fontan group (p = 0.003). Habitual exercise was not associated with VO 2max in subjects with a Fontan as compared to biventricular circulation. Further research is necessary to understand why their habitual exercise is ineffective and/or what aspects of the Fontan circulation disrupt this association.
O'Byrne, Michael L; Desai, Sanyukta; Lane, Megan; McBride, Michael; Paridon, Stephen; Goldmuntz, Elizabeth
2016-01-01
Background Increasing habitual exercise has been associated with improved cardiopulmonary exercise testing (CPET) performance, specifically maximal oxygen consumption in children with operatively corrected congenital heart disease. This has not been studied in children following Fontan palliation, a population in whom CPET performance is dramatically diminished. Methods A single-center cross-sectional study with prospective and retrospective data collection was performed that assessed habitual exercise preceding a clinically indicated CPET in children and adolescents with Fontan palliation, transposition of the great arteries following arterial switch operation (TGA), and normal cardiac anatomy without prior operation. Data from contemporaneous clinical reports and imaging studies were collected. The association between percent predicted VO2max and habitual exercise duration adjusted for known covariates was tested. Results A total of 175 subjects (75 post Fontan, 20 with TGA, and 80 with normal cardiac anatomy) were enrolled. VO2max was lower in the Fontan group than patients with normal cardiac anatomy (p<0.0001) or TGA (p<0.0001). In Fontan subjects, both univariate and multivariate analysis failed to demonstrate a significant association between habitual exercise and VO2max (p=0.6), in sharp contrast to cardiac normal subjects. In multivariate analysis, increasing age was the only independent risk factor associated with decreasing VO2max in the Fontan group (p=0.003). Discussion Habitual exercise was not associated with VO2max in subjects with a Fontan as compared to biventricular circulation. Further research is necessary to understand why their habitual exercise is ineffective and/or what aspects of the Fontan circulation disrupt this association. PMID:27878634
A Single Bout of Moderate Aerobic Exercise Improves Motor Skill Acquisition.
Statton, Matthew A; Encarnacion, Marysol; Celnik, Pablo; Bastian, Amy J
2015-01-01
Long-term exercise is associated with improved performance on a variety of cognitive tasks including attention, executive function, and long-term memory. Remarkably, recent studies have shown that even a single bout of aerobic exercise can lead to immediate improvements in declarative learning and memory, but less is known about the effect of exercise on motor learning. Here we sought to determine the effect of a single bout of moderate intensity aerobic exercise on motor skill learning. In experiment 1, we investigated the effect of moderate aerobic exercise on motor acquisition. 24 young, healthy adults performed a motor learning task either immediately after 30 minutes of moderate intensity running, after running followed by a long rest period, or after slow walking. Motor skill was assessed via a speed-accuracy tradeoff function to determine how exercise might differentially affect two distinct components of motor learning performance: movement speed and accuracy. In experiment 2, we investigated both acquisition and retention of motor skill across multiple days of training. 20 additional participants performed either a bout of running or slow walking immediately before motor learning on three consecutive days, and only motor learning (no exercise) on a fourth day. We found that moderate intensity running led to an immediate improvement in motor acquisition for both a single session and on multiple sessions across subsequent days, but had no effect on between-day retention. This effect was driven by improved movement accuracy, as opposed to speed. However, the benefit of exercise was dependent upon motor learning occurring immediately after exercise-resting for a period of one hour after exercise diminished the effect. These results demonstrate that moderate intensity exercise can prime the nervous system for the acquisition of new motor skills, and suggest that similar exercise protocols may be effective in improving the outcomes of movement rehabilitation programs.
A Single Bout of Moderate Aerobic Exercise Improves Motor Skill Acquisition
Statton, Matthew A.; Encarnacion, Marysol; Celnik, Pablo; Bastian, Amy J.
2015-01-01
Long-term exercise is associated with improved performance on a variety of cognitive tasks including attention, executive function, and long-term memory. Remarkably, recent studies have shown that even a single bout of aerobic exercise can lead to immediate improvements in declarative learning and memory, but less is known about the effect of exercise on motor learning. Here we sought to determine the effect of a single bout of moderate intensity aerobic exercise on motor skill learning. In experiment 1, we investigated the effect of moderate aerobic exercise on motor acquisition. 24 young, healthy adults performed a motor learning task either immediately after 30 minutes of moderate intensity running, after running followed by a long rest period, or after slow walking. Motor skill was assessed via a speed-accuracy tradeoff function to determine how exercise might differentially affect two distinct components of motor learning performance: movement speed and accuracy. In experiment 2, we investigated both acquisition and retention of motor skill across multiple days of training. 20 additional participants performed either a bout of running or slow walking immediately before motor learning on three consecutive days, and only motor learning (no exercise) on a fourth day. We found that moderate intensity running led to an immediate improvement in motor acquisition for both a single session and on multiple sessions across subsequent days, but had no effect on between-day retention. This effect was driven by improved movement accuracy, as opposed to speed. However, the benefit of exercise was dependent upon motor learning occurring immediately after exercise–resting for a period of one hour after exercise diminished the effect. These results demonstrate that moderate intensity exercise can prime the nervous system for the acquisition of new motor skills, and suggest that similar exercise protocols may be effective in improving the outcomes of movement rehabilitation programs. PMID:26506413
Carbohydrate and exercise performance: the role of multiple transportable carbohydrates.
Jeukendrup, Asker E
2010-07-01
Carbohydrate feeding has been shown to be ergogenic, but recently substantial advances have been made in optimizing the guidelines for carbohydrate intake during prolonged exercise. It was found that limitations to carbohydrate oxidation were in the absorptive process most likely because of a saturation of carbohydrate transporters. By using a combination of carbohydrates that use different intestinal transporters for absorption it was shown that carbohydrate delivery and oxidation could be increased. Studies demonstrated increases in exogenous carbohydrate oxidation rates of up to 65% of glucose: fructose compared with glucose only. Exogenous carbohydrate oxidation rates reach values of 1.75 g/min whereas previously it was thought that 1 g/min was the absolute maximum. The increased carbohydrate oxidation with multiple transportable carbohydrates was accompanied by increased fluid delivery and improved oxidation efficiency, and thus the likelihood of gastrointestinal distress may be diminished. Studies also demonstrated reduced fatigue and improved exercise performance with multiple transportable carbohydrates compared with a single carbohydrate. Multiple transportable carbohydrates, ingested at high rates, can be beneficial during endurance sports in which the duration of exercise is 3 h or more.
Air Current Applied to the Face Improves Exercise Performance in Patients with COPD.
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.
Peeler, Jason; Ripat, Jacquie
2018-01-01
Knee osteoarthritis has a lifetime risk of nearly one in two, with obese individuals being most susceptible. While exercise is universally recognized as a critical component for management, unsafe or ineffective exercise frequently leads to exacerbation of joint symptoms. Evaluate the effect of a 12week lower body positive pressure (LBPP) supported low-load treadmill walking program on knee pain, joint function, and performance of daily activities in patients with knee osteoarthritis (OA). Prospective, observational, repeated measures investigation. Community based, multidisciplinary musculoskeletal medicine clinic. Thirty-one patients, aged 50-75, with a BMI ≥25kg/m 2 and radiographic confirmed mild to moderate knee OA. Twelve week LBPP treadmill walking exercise regimen. The Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Canadian Occupational Performance Measure (COPM) were used to quantify joint symptoms and patient function; isokinetic thigh muscle strength was evaluated; and a 10-point VAS was used to quantify acute knee pain while walking. Baseline and follow-up data were compared in order to examine the effect of the 12week exercise intervention. There was a significant difference between baseline and follow-up data: KOOS and COPM scores both improved; thigh muscle strength increased; and acute knee pain during full weight bearing walking diminished significantly. Participation in a 12week LBPP supported treadmill walking exercise regimen significantly enhanced patient function and quality of life, as well as the ability to perform activities of daily living that patient's self-identified as being important, yet difficult to perform. Copyright © 2017 Elsevier B.V. All rights reserved.
Neuromuscular Adaptations to Reduced Use
NASA Technical Reports Server (NTRS)
Ploutz-Snyder, Lori
2009-01-01
This viewgraph presentation reviews the studies done to reduce neuromuscular strength loss during unilateral lower limb suspension (ULLS). Since there are animals that undergo fairly long periods of muscular disuse without any or minimal muscular atrophy, there is an answer to that might be applicable to human in situations that require no muscular use to diminish the effects of muscular atrophy. Three sets of ULLS studies were reviewed indicated that muscle strength decreased more than the muscle mass. The study reviewed exercise countermeasures to combat the atrophy, including: ischemia maintained during Compound muscle action potential (CMAP), ischemia and low load exercise, Japanese kaatsu, and the potential for rehabilitation or situations where heavy loading is undesirable. Two forms of countermeasures to unloading have been successful, (1) high-load resistance training has maintained muscle mass and strength, and low load resistance training with blood flow restriction (LL(sub BFR)). The LL(sub BFR) has been shown to increase muscle mass and strength. There has been significant interest in Tourniquet training. An increase in Growth Hormone(GH) has been noted for LL(sub BFR) exercise. An experimental study with 16 subjects 8 of whom performed ULLS, and 8 of whom performed ULLS and LL(sub BFR) exercise three times per week during the ULLS. Charts show the results of the two groups, showing that performing LL(sub BFR) exercise during 30 days of ULLS can maintain muscle size and strength and even improve muscular endurance.
Exercise-induced oxidative stress and hypoxic exercise recovery.
Ballmann, Christopher; McGinnis, Graham; Peters, Bridget; Slivka, Dustin; Cuddy, John; Hailes, Walter; Dumke, Charles; Ruby, Brent; Quindry, John
2014-04-01
Hypoxia due to altitude diminishes performance and alters exercise oxidative stress responses. While oxidative stress and exercise are well studied, the independent impact of hypoxia on exercise recovery remains unknown. Accordingly, we investigated hypoxic recovery effects on post-exercise oxidative stress. Physically active males (n = 12) performed normoxic cycle ergometer exercise consisting of ten high:low intensity intervals, 20 min at moderate intensity, and 6 h recovery at 975 m (normoxic) or simulated 5,000 m (hypoxic chamber) in a randomized counter-balanced cross-over design. Oxygen saturation was monitored via finger pulse oximetry. Blood plasma obtained pre- (Pre), post- (Post), 2 h post- (2Hr), 4 h post- (4Hr), and 6 h (6Hr) post-exercise was assayed for Ferric Reducing Ability of Plasma (FRAP), Trolox Equivalent Antioxidant Capacity (TEAC), Lipid Hydroperoxides (LOOH), and Protein Carbonyls (PC). Biopsies from the vastus lateralis obtained Pre and 6Hr were analyzed by real-time PCR quantify expression of Heme oxygenase 1 (HMOX1), Superoxide Dismutase 2 (SOD2), and Nuclear factor (euthyroid-derived2)-like factor (NFE2L2). PCs were not altered between trials, but a time effect (13 % Post-2Hr increase, p = 0.044) indicated exercise-induced blood oxidative stress. Plasma LOOH revealed only a time effect (p = 0.041), including a 120 % Post-4Hr increase. TEAC values were elevated in normoxic recovery versus hypoxic recovery. FRAP values were higher 6Hr (p = 0.045) in normoxic versus hypoxic recovery. Exercise elevated gene expression of NFE2L2 (20 % increase, p = 0.001) and SOD2 (42 % increase, p = 0.003), but hypoxic recovery abolished this response. Data indicate that recovery in a hypoxic environment, independent of exercise, may alter exercise adaptations to oxidative stress and metabolism.
Snow, Nicholas J.; Mang, Cameron S.; Roig, Marc; Boyd, Lara A.
2016-01-01
Introduction There is evidence for beneficial effects of acute and long-term exercise interventions on several forms of memory, including procedural motor learning. In the present study we examined how performing a single bout of continuous moderate intensity aerobic exercise would impact motor skill acquisition and retention in young healthy adults, compared to a period of rest. We hypothesized that exercise would improve motor skill acquisition and retention, compared to motor practice alone. Materials and Methods Sixteen healthy adults completed sessions of aerobic exercise or seated rest that were immediately followed by practice of a novel motor task (practice). Exercise consisted of 30 minutes of continuous cycling at 60% peak O2 uptake. Twenty-four hours after practice, we assessed motor learning with a no-exercise retention test (retention). We also quantified changes in offline motor memory consolidation, which occurred between practice and retention (offline). Tracking error was separated into indices of temporal precision and spatial accuracy. Results There were no differences between conditions in the timing of movements during practice (p = 0.066), at retention (p = 0.761), or offline (p = 0.966). However, the exercise condition enabled participants to maintain spatial accuracy during practice (p = 0.477); whereas, following rest performance diminished (p = 0.050). There were no significant differences between conditions at retention (p = 0.532) or offline (p = 0.246). Discussion An acute bout of moderate-intensity aerobic exercise facilitated the maintenance of motor performance during skill acquisition, but did not influence motor learning. Given past work showing that pairing high intensity exercise with skilled motor practice benefits learning, it seems plausible that intensity is a key modulator of the effects of acute aerobic exercise on changes in complex motor behavior. Further work is necessary to establish a dose-response relationship between aerobic exercise and motor learning. PMID:26901664
Effect of gender on fatigue and recovery following maximal intensity repeated sprint performance.
Laurent, C M; Green, J M; Bishop, P A; Sjökvist, J; Schumacker, R E; Richardson, M T; Curtner-Smith, M
2010-09-01
This study investigated the effects of gender on repeated, maximal-intensity intermittent sprint exercise following variable day-to-day recovery periods. Sixteen volunteers (8 men, 8 women) performed four trials of high-intensity intermittent sprint exercise consisting of three bouts of eight 30 m sprints (total of 24 sprints). Following completion of the baseline trial, in repeated-measures design, participants were assigned, in counter-balanced order, variable recovery periods of 24, 48, and 72 h whereupon they repeated an identical exercise trial. Results from a series of 4 (trial) x 3 (bout) repeated measures ANOVAs revealed men produced significantly (P < 0.01) faster times throughout all bouts and trials of repeated sprint exercise. Additionally, women exhibited significantly lower (P < 0.05) blood lactate concentration and significantly lower (P < 0.05) decrement in performance, indicating increased resistance to fatigue during repeated exercise sessions. There were no significant differences (P > 0.05) between genders for heart rate or rating of perceived exertion during or following trials. There were no significant differences for overall sprint performance within either gender among trials. These results indicate men, while able to produce higher absolute power outputs (i.e., lower sprint time), demonstrate higher decrement scores within a trial compared to women, thus suggesting women may recover faster and fatigue less. Also, gender differences affecting recovery within in a trial were observed to be diminished between trials (i.e., day-to-day recovery) of maximal intermittent sprint work evidenced by the observed stability of performance between trials following various recovery durations.
Pre-cooling for endurance exercise performance in the heat: a systematic review
2012-01-01
Background Endurance exercise capacity diminishes under hot environmental conditions. Time to exhaustion can be increased by lowering body temperature prior to exercise (pre-cooling). This systematic literature review synthesizes the current findings of the effects of pre-cooling on endurance exercise performance, providing guidance for clinical practice and further research. Methods The MEDLINE, EMBASE, CINAHL, Web of Science and SPORTDiscus databases were searched in May 2012 for studies evaluating the effectiveness of pre-cooling to enhance endurance exercise performance in hot environmental conditions (≥ 28°C). Studies involving participants with increased susceptibility to heat strain, cooling during or between bouts of exercise, and protocols where aerobic endurance was not the principle performance outcome were excluded. Potential publications were assessed by two independent reviewers for inclusion and quality. Means and standard deviations of exercise performance variables were extracted or sought from original authors to enable effect size calculations. Results In all, 13 studies were identified. The majority of studies contained low participant numbers and/or absence of sample size calculations. Six studies used cold water immersion, four crushed ice ingestion and three cooling garments. The remaining study utilized mixed methods. Large heterogeneity in methodological design and exercise protocols was identified. Effect size calculations indicated moderate evidence that cold water immersion effectively improved endurance performance, and limited evidence that ice slurry ingestion improved performance. Cooling garments were ineffective. Most studies failed to document or report adverse events. Low participant numbers in each study limited the statistical power of certain reported trends and lack of blinding could potentially have introduced either participant or researcher bias in some studies. Conclusions Current evidence indicates cold water immersion may be the most effective method of pre-cooling to improve endurance performance in hot conditions, although practicality must be considered. Ice slurry ingestion appears to be the most promising practical alternative. Interestingly, cooling garments appear of limited efficacy, despite their frequent use. Mechanisms behind effective pre-cooling remain uncertain, and optimal protocols have yet to be established. Future research should focus on standardizing exercise performance protocols, recruiting larger participant numbers to enable direct comparisons of effectiveness and practicality for each method, and ensuring potential adverse events are evaluated. PMID:23249542
NASA Technical Reports Server (NTRS)
Smorawinski, J.; Nazar, K.; Kaciuza-Uscilko; Kaminska, E.; Kodrzycka, A.; Bicz, B.; Greenleaf, J. E.
2001-01-01
To test the hypotheses that short-term bed rest (BR) deconditioning influences metabolic, cardiorespiratory and neurohormonal responses to exercise and that these effects depend on the subjects' training status, 12 sedentary men, and 10 endurance- and 10 strength-trained athletes were submitted to three-day BR. Before and after BR they performed incremental exercise tests until volitional exhaustion. Respiratory gas exchange and HR were recorded continuously and stroke volume (SV) was measured at submaximal loads. Blood was taken for lactate [LA], adrenaline [A], noradrenaline [NA], renin activity (PRA), growth hormone [hGH], testosterone and cortisol determination. Reduction of peak oxygen uptake (V02peak) after BR was greater in the endurance athletes than in the remaining groups (17 % vs. 10%). Decrements in VO2peak correlated positively with the initial values (r = 0.73, p is less than 0.001). Resting and exercise respiratory exchange ratios were increased in athletes. Cardiac output was unchanged by BR in all groups, but exercise HR was increased and SV diminished in the sedentary subjects. The submaximal [LA] and [LA] thresholds were decreased the in endurance athletes from 71 to 60% V02 peak (p is less than0.001), they also had an earlier increase in [NA], an attenuated increase in [hGH], and accentuated PRA and cortisol elevations during exercise. These effects were insignificant in the remaining subjects. In conclusion: reduction of exercise performance and modifications in neurohormonal response to exercise after BR depend on the previous level and mode of physical training, being the most pronounced in the endurance athletes.
NASA Technical Reports Server (NTRS)
Smorawinski, J.; Nazar, K.; Kaciuza-Uscilko, H.; Kaminska, E.; Cybulski, G.; Kodrzycka, A.; Bice, B.; Greenleaf, J. E.; Sun, Sid (Technical Monitor)
2001-01-01
To test the hypotheses that short-term bed rest (BR) deconditioning influences metabolic, cardiorespiratory and neurohormonal responses to exercise and that these effects depend on the subjects' training status 12 sedentary men, and 10 endurance- and 10 strength-trained athletes were submitted to three-day BR. Before and after BR they performed incremental exercise test until volitional exhaustion. Respiratory gas exchange and HR were recorded continuously and stroke volume (SV) was measured at submaximal loads. Blood was taken for lactate [LA], adrenaline [A], noradrenaline, [NA], renting activity (PRA), growth hormone [hGH], testosterone and cortisol determination. Reduction of peak oxygen uptake (VO2peak) after BR was greater in the endurance athletes (than in the remaining groups (17 % vs. 100%). Decrements in VO2peak correlated positively with the initial values (r = 0.73, p less than 0.001). Resting and exercise respiratory exchange ratios were increased in athletes. Cardiac output was unchanged by BR in all groups, but exercise HR was increased and SV diminished in the sedentary subjects. The submaximal [LA] and [LA] thresholds were decreased the in endurance athletes from 71 to 60 %VO2 peak (p less than 0.001); they also had an earlier increase in [NA], and an attenuated increase in [hGH), and accentuated PRA and cortisol elevations during exercise. These effects were insignificant in the remaining subjects. In conclusion: reduction of exercise performance and modifications in neurohormonal response to exercise after BR depend on the previous level and mode of physical training, being the most pronounced in the endurance athletes.
NASA Technical Reports Server (NTRS)
Smorawinski, J.; Nazar, K.; Kaciuba-Uscilko, H.; Kaminska, E.; Cybulski, G.; Kodrzycka, A.; Bicz, B.; Greenleaf, J. E.
2001-01-01
To test the hypotheses that short-term bed-rest (BR) deconditioning influences metabolic, cardiorespiratory, and neurohormonal responses to exercise and that these effects depend on the subjects' training status, 12 sedentary men and 10 endurance- and 10 strength-trained athletes were submitted to 3-day BR. Before and after BR they performed incremental exercise test until volitional exhaustion. Respiratory gas exchange and heart rate (HR) were recorded continuously, and stroke volume (SV) was measured at submaximal loads. Blood was taken for lactate concentration ([LA]), epinephrine concentration ([Epi]), norepinephrine concentration ([NE]), plasma renin activity (PRA), human growth hormone concentration ([hGH]), testosterone, and cortisol determination. Reduction of peak oxygen uptake (VO(2 peak)) after BR was greater in the endurance athletes than in the remaining groups (17 vs. 10%). Decrements in VO(2 peak) correlated positively with the initial values (r = 0.73, P < 0.001). Resting and exercise respiratory exchange ratios were increased in athletes. Cardiac output was unchanged by BR in all groups, but exercise HR was increased and SV diminished in the sedentary subjects. The submaximal [LA] and [LA] thresholds were decreased in the endurance athletes from 71 to 60% VO(2 peak) (P < 0.001); they also had an earlier increase in [NE], an attenuated increase in [hGH], and accentuated PRA and cortisol elevations during exercise. These effects were insignificant in the remaining subjects. In conclusion, reduction of exercise performance and modifications in neurohormonal response to exercise after BR depend on the previous level and mode of physical training, being the most pronounced in the endurance athletes.
Smorawiński, J; Nazar, K; Kaciuba-Uscilko, H; Kamińska, E; Cybulski, G; Kodrzycka, A; Bicz, B; Greenleaf, J E
2001-07-01
To test the hypotheses that short-term bed-rest (BR) deconditioning influences metabolic, cardiorespiratory, and neurohormonal responses to exercise and that these effects depend on the subjects' training status, 12 sedentary men and 10 endurance- and 10 strength-trained athletes were submitted to 3-day BR. Before and after BR they performed incremental exercise test until volitional exhaustion. Respiratory gas exchange and heart rate (HR) were recorded continuously, and stroke volume (SV) was measured at submaximal loads. Blood was taken for lactate concentration ([LA]), epinephrine concentration ([Epi]), norepinephrine concentration ([NE]), plasma renin activity (PRA), human growth hormone concentration ([hGH]), testosterone, and cortisol determination. Reduction of peak oxygen uptake (VO(2 peak)) after BR was greater in the endurance athletes than in the remaining groups (17 vs. 10%). Decrements in VO(2 peak) correlated positively with the initial values (r = 0.73, P < 0.001). Resting and exercise respiratory exchange ratios were increased in athletes. Cardiac output was unchanged by BR in all groups, but exercise HR was increased and SV diminished in the sedentary subjects. The submaximal [LA] and [LA] thresholds were decreased in the endurance athletes from 71 to 60% VO(2 peak) (P < 0.001); they also had an earlier increase in [NE], an attenuated increase in [hGH], and accentuated PRA and cortisol elevations during exercise. These effects were insignificant in the remaining subjects. In conclusion, reduction of exercise performance and modifications in neurohormonal response to exercise after BR depend on the previous level and mode of physical training, being the most pronounced in the endurance athletes.
Wright, Katherine E; Lyons, Thomas S; Navalta, James W
2013-05-01
The authors of this study examined the effects of muscle fatigue on balance indices and recovery time in recreationally trained individuals after incremental tests on a treadmill and a cycle ergometer. Sixteen participants (male N = 11, female N = 5) (mean age = 21.2 ± 2 years) completed this study. Balance measures were performed on a Biodex Balance System via the Dynamic Balance Test. Balance was measured pre-exercise, immediately post-exercise, and at 3-, 6-, 9-, 12-, 15-, 18-, and 21-min post-exercise. Immediately following the fatiguing treadmill test, balance increased significantly in the overall stability index (SI) (from 4.38 ± 2.48 to 6.09 ± 1.80) and the anterior/posterior index (API) (from 3.49 ± 2.18 to 5.28 ± 1.81) (p < 0.01). Immediately following the fatiguing cycle test, balance was not altered significantly in SI or API. Balance was not altered significantly for the medial/lateral index for either exercise test at any time point. Additionally, there were no significant differences in time to recovery. At 12-min post-exercise, all indices were below pre-exercise values, indicating that fatiguing exercise has a positive effect on balance over time. These results are consistent with previous research, suggesting that any effects of fatigue on balance are seen immediately and are diminished as time after exercise increases.
This investigation was designed to answer three questions: (1) Does repetition of a ketosis following a 10 mile walk cause adaptive responses; (2...Does repeated exposure to cold result in a diminished ketotic response; (3) Do women show a post-exercise ketosis like men. Protocols for the three...exercise ketosis similar to that shown by men, despite much individual variability. Prolonged moderate exercise, exposure to cold and starvation all produce similar metabolic effects. (Author)
Evaluation of Efficacy of Preventive Measures under Hypokinesia.
ERIC Educational Resources Information Center
Zorbas, Yan G.; Matveyev, Ivan O.
1987-01-01
The study evaluated the efficacy of physical exercise alone and in combination with other preventive measures with 24 adult male subjects kept under a bed rest regime. It was concluded that physical exercise was the most reliable measure in counteracting neuromuscular system disorders under diminished muscular activity conditions. (Author/DB)
Hilbert, M; Shushakov, V; Maassen, N
2012-02-01
Acidification has been reported to provide protective effects on force production in vitro. Thus, in this study, we tested if respiratory acid-base changes influence muscle function and excitability in vivo. Nine subjects performed strenuous, intermittent hand grip exercises (10 cycles of 15 s of work/45 s of rest) under respiratory acidosis by CO(2) rebreathing, alkalosis by hyperventilation, or control. The Pco(2), pH, K(+) concentration ([K(+)]), and Na(+) concentration were measured in venous and arterialized blood. Compound action potentials (M-wave) were elicited to examine the excitability of the sarcolemma. The surface electromyogram (EMG) was recorded to estimate the central drive to the muscle. The lowest venous pH during the exercise period was 7.24 ± 0.03 in controls, 7.31 ± 0.05 with alkalosis, and 7.17 ± 0.04 with acidosis (P < 0.001). The venous [K(+)] rose to similar maximum values in all conditions (6.2 ± 0.8 mmol/l). The acidification reduced the decline in contraction speed (P < 0.001) but decreased the M-wave area to 73.4 ± 19.8% (P < 0.001) of the initial value. After the first exercise cycle, the M-wave area was smaller with acidosis than with alkalosis, and, after the second cycle, it was smaller with acidosis than with the control condition (P < 0.001). The duration of the M-wave was not affected. Acidification diminished the reduction in performance, although the M-wave area during exercise was decreased. Respiratory alkalosis stabilized the M-wave area without influencing performance. Thus, we did not find a direct link between performance and alteration of excitability of the sarcolemma due to changes in pH in vivo.
Muscle glycogen depletion and subsequent replenishment affect anaerobic capacity of horses.
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.
Creatine supplementation with specific view to exercise/sports performance: an update
2012-01-01
Creatine is one of the most popular and widely researched natural supplements. The majority of studies have focused on the effects of creatine monohydrate on performance and health; however, many other forms of creatine exist and are commercially available in the sports nutrition/supplement market. Regardless of the form, supplementation with creatine has regularly shown to increase strength, fat free mass, and muscle morphology with concurrent heavy resistance training more than resistance training alone. Creatine may be of benefit in other modes of exercise such as high-intensity sprints or endurance training. However, it appears that the effects of creatine diminish as the length of time spent exercising increases. Even though not all individuals respond similarly to creatine supplementation, it is generally accepted that its supplementation increases creatine storage and promotes a faster regeneration of adenosine triphosphate between high intensity exercises. These improved outcomes will increase performance and promote greater training adaptations. More recent research suggests that creatine supplementation in amounts of 0.1 g/kg of body weight combined with resistance training improves training adaptations at a cellular and sub-cellular level. Finally, although presently ingesting creatine as an oral supplement is considered safe and ethical, the perception of safety cannot be guaranteed, especially when administered for long period of time to different populations (athletes, sedentary, patient, active, young or elderly). PMID:22817979
Stress in crisis managers: evidence from self-report and psychophysiological assessments.
Janka, A; Adler, C; Fischer, L; Perakakis, P; Guerra, P; Duschek, S
2015-12-01
Directing disaster operations represents a major professional challenge. Despite its importance to health and professional performance, research on stress in crisis management remains scarce. The present study aimed to investigate self-reported stress and psychophysiological stress responses in crisis managers. For this purpose, 30 crisis managers were compared with 30 managers from other disciplines, in terms of self-reported stress, health status and psychophysiological reactivity to crisis-related and non-specific visual and acoustic aversive stimuli and cognitive challenge. Crisis managers reported lower stress levels, a more positive strain-recuperation-balance, greater social resources, reduced physical symptoms, as well as more physical exercise and less alcohol consumption. They exhibited diminished electrodermal and heart rate responses to crisis-related and non-specific stressors. The results indicate reduced stress and physical complaints, diminished psychophysiological stress reactivity, and a healthier life-style in crisis managers. Improved stress resistance may limit vulnerability to stress-related performance decline and facilitate preparedness for major incidents.
Abnormal cardiovascular response to exercise in hypertension: contribution of neural factors.
Mitchell, Jere H
2017-06-01
During both dynamic (e.g., endurance) and static (e.g., strength) exercise there are exaggerated cardiovascular responses in hypertension. This includes greater increases in blood pressure, heart rate, and efferent sympathetic nerve activity than in normal controls. Two of the known neural factors that contribute to this abnormal cardiovascular response are the exercise pressor reflex (EPR) and functional sympatholysis. The EPR originates in contracting skeletal muscle and reflexly increases sympathetic efferent nerve activity to the heart and blood vessels as well as decreases parasympathetic efferent nerve activity to the heart. These changes in autonomic nerve activity cause an increase in blood pressure, heart rate, left ventricular contractility, and vasoconstriction in the arterial tree. However, arterial vessels in the contracting skeletal muscle have a markedly diminished vasoconstrictor response. The markedly diminished vasoconstriction in contracting skeletal muscle has been termed functional sympatholysis. It has been shown in hypertension that there is an enhanced EPR, including both its mechanoreflex and metaboreflex components, and an impaired functional sympatholysis. These conditions set up a positive feedback or vicious cycle situation that causes a progressively greater decrease in the blood flow to the exercising muscle. Thus these two neural mechanisms contribute significantly to the abnormal cardiovascular response to exercise in hypertension. In addition, exercise training in hypertension decreases the enhanced EPR, including both mechanoreflex and metaboreflex function, and improves the impaired functional sympatholysis. These two changes, caused by exercise training, improve the muscle blood flow to exercising muscle and cause a more normal cardiovascular response to exercise in hypertension. Copyright © 2017 the American Physiological Society.
Effects of humoral factors on ventilation kinetics during recovery after impulse-like exercise.
Afroundeh, R; Arimitsu, T; Yamanaka, R; Lian, C; Yunoki, T; Yano, Tokuo
2012-06-01
To clarify the ventilatory kinetics during recovery after impulse-like exercise, subjects performed one impulse-like exercise test (one-impulse) and a five-times repeated impulse-like exercises test (five-impulse). Duration and intensity of the impulse-like exercise were 20 sec and 400 watts (80 rpm), respectively. Although blood pH during recovery (until 10 min) was significantly lower in the five-impulse test than in the one-impulse test, ventilation (.VE) in the two tests was similar except during the first 30 sec of recovery, in which it was higher in the five-impulse test. In one-impulse, blood CO2 pressure (PCO2) was significantly increased at 1 min during recovery and then returned to the pre-exercise level at 5 min during recovery. In the five-impulse test, PCO2 at 1 min during recovery was similar to the pre-exercise level, and then it decreased to a level lower than the pre-exercise level at 5 min during recovery. Accordingly, PCO2 during recovery (until 30 min) was significantly lower in the five-impulse than in one-impulse test..VE and pH during recovery showed a curvilinear relationship, and at the same pH, ventilation was higher in the one-impulse test. These results suggest that ventilatory kinetics during recovery after impulse-like exercise is attributed partly to pH, but the stimulatory effect of lower pH is diminished by the inhibitory effect of lower PCO2.
Heart rate variability and aerobic fitness.
De Meersman, R E
1993-03-01
Heart rate variability, a noninvasive marker of parasympathetic activity, diminishes with aging and is augmented after exercise training. Whether habitual exercise over time can attenuate this loss is unknown. This cross-sectional investigation compared 72 male runners, aged 15 to 83 to 72 age- and weight-matched sedentary control subjects for the amplitude of their heart rate variability. Heart rate variability was assessed during rest while subjects were breathing at a rate of 6 breaths per minute and at an augmented tidal volume (tidal volume = 30% of vital capacity). Fitness levels were assessed with on-line, open-circuit spirometry while subjects were performing an incremental stress test. Overall results between the two groups showed that the physically active group had significantly higher fitness levels (p < 0.001), which were associated with significantly higher levels of heart rate variability, when compared with their sedentary counterparts (p < 0.001). These findings provide suggestive evidence for habitual aerobic exercise as a beneficial modulator of heart rate variability in an aging population.
Cardiovascular health and fitness after stroke.
Ivey, F M; Macko, R F; Ryan, A S; Hafer-Macko, C E
2005-01-01
Stroke patients have profound cardiovascular and muscular deconditioning, with metabolic fitness levels that are about half those found in age-matched sedentary controls. Physical deconditioning, along with elevated energy demands of hemiparetic gait, define a detrimental combination termed diminished physiological fitness reserve that can greatly limit that can greatly limit performance of activities of daily living. The physiological features that underlie worsening metabolic fitness in the chronic phase of stroke include gross muscular atrophy, altered muscle molecular phenotype, increased intramuscular area fat, elevated tissue inflammatory markers, and diminished peripheral blood flow dynamics. Epidemiological evidence further suggests that the reduced cardiovascular fitness and secondary biological changes in muscle may propagate components of the metabolic syndrome, conferring added morbidity and mortality risk. This article reviews some of the consequences of poor fitness in chronic stroke and the potential biological underpinnings that support a rationale for more aggressive approaches to exercise therapy in this population.
Effect of exercise on the pseudodiabetes of bed rest
NASA Technical Reports Server (NTRS)
Greenleaf, J. E.
1982-01-01
The effect of intensive isotonic exercise and isometric exercise (with its low metabolic rate) during bed rest on plasma insulin and glucose tolerance test was investigated. The subjects were seven healthy men, 19 to 22 years in age, 166 to 188 cm in height, and 62.40 to 103.80 kg in weight; maximal oxygen uptakes ranged from 3.36 to 4.38 liters/min. It appears that bed-rest-induced glucose intolerance is diminished with increasing energy expenditure during both bed rest and recovery.
Protective effect of exercise and sildenafil on acute stress and cognitive function.
Ozbeyli, Dilek; Gokalp, Ayse Gizem; Koral, Tolga; Ocal, Onur Yuksel; Dogan, Berkay; Akakin, Dilek; Yuksel, Meral; Kasimay, Ozgur
2015-11-01
There are contradictory results about the effects of exercise and sildenafil on cognitive functions. To investigate the effects of sildenafil pretreatment and chronic exercise on anxiety and cognitive functions. Wistar rats (n=42) were divided as sedentary and exercise groups. A moderate-intensity swimming exercise was performed for 6 weeks, 5 days/week, 1h/day. Some of the rats were administered orogastrically with sildenafil (25mg/kg/day) either acutely or chronically. Exposure to cat odor was used for induction of stress. The level of anxiety was evaluated by elevated plus maze test, while object recognition test was used to determine cognitive functions. Brain tissues were removed for the measurement of myeloperoxidase (MPO), malondialdehyde (MDA), nitric oxide levels, lucigenin-enhanced chemiluminescence, and for histological analysis. Increased MPO and MDA levels in sedentary-stressed rats were decreased with sildenafil applications. Chronic exercise inhibited the increase in MPO levels. Increased nitric oxide and lucigenin chemiluminescence levels in sedentary-stressed rats, were diminished with chronic sildenafil pretreatment. The time spent in the open arms of the plus maze was declined in sedentary-stressed rats, while chronic sildenafil pretreatment increased the time back to that in non-stressed rats. Acute sildenafil application to exercised rats prolonged the time spent in open arms as compared to non-treated exercise group. The time spent with the novel object, which was decreased in sedentary-stressed rats, was increased with sildenafil pretreatment. Our results suggest that sildenafil pretreatment or exercise exerts a protective effect against acute stress and improves cognitive functions by decreasing oxidative damage. Copyright © 2015 Elsevier Inc. All rights reserved.
Spoo, J W; Zoran, D L; Downey, R L; Bischoff, K; Wakshlag, J J
2015-10-01
The aim of the study was to assess the physiological and antioxidant status before and after a 4 h search and rescue field exercise, with handlers, under warm-weather conditions performing activities compared to a control group of similarly trained dogs at rest. Serum chemistry demonstrated a decrease in serum sodium (Na) and potassium (K) in both exercising and control groups, however only Na was decreased significantly (P < 0.05) after exercise and hematocrits (HCTs) remained unchanged. The exercise group demonstrated significantly decreased serum phosphorus (P) and magnesium (Mg) compared to pre-exercise values, as did the control group (P < 0.025). There was also a significant increase in creatinine kinase concentrations in the exercise groups (P < 0.025). Serum non-esterified fatty acids were increased only in the exercise group after exercise, suggesting fat mobilization to produce energy. The mean total serum antioxidant potential in searching dogs was no different from the pre- and post-exercise values in the control dogs. Serum vitamin E concentrations did not differ between the two groups, with a decreasing trend in both groups. There was a modest decrease in serum uric acid in the control group, while there was a significant rise after exercise in the searching group (P < 0.01). Multiple changes in serum chemistry, HCTs and blood gases were documented in this study, and were similar to those observed after other endurance activities. The lack of hemoconcentration in this field search exercise suggested that even in extreme environmental conditions (heat and humidity), dogs with access to water do not experience significant dehydration or diminished antioxidant status. Copyright © 2015. Published by Elsevier Ltd.
Impact of Blood Flow Restriction Exercise on Muscle Fatigue Development and Recovery.
Husmann, Florian; Mittlmeier, Thomas; Bruhn, Sven; Zschorlich, Volker; Behrens, Martin
2018-03-01
The present study was designed to provide mechanistic insight into the time course and etiology of muscle fatigue development and recovery during and after low-intensity exercise when it is combined with blood flow restriction (BFR). Seventeen resistance-trained males completed four sets of low-intensity isotonic resistance exercise under two experimental conditions: knee extension exercise (i) with BFR and (ii) without BFR (CON). Neuromuscular tests were performed before, during (immediately after each set of knee extension exercise), and 1, 2, 4, and 8 min after each experimental condition. Maximal voluntary torque, quadriceps twitch torque in response to paired electrical stimuli at 10 Hz (PS10) and 100 Hz (PS100), PS10·PS100 ratio as an index of low-frequency fatigue, and voluntary activation were measured under isometric conditions. Perceptual and EMG data were recorded during each exercise condition. After the first set of exercise, BFR induced significantly greater reductions in maximal voluntary torque, PS100, and PS10·PS100 ratio compared with CON. These parameters progressively declined throughout the BFR protocol but recovered substantially within 2 min postexercise when blood flow was restored. Neither a progressive decline in the course of the exercise protocol nor a substantial recovery of these parameters occurred during and after CON. Only at exercise termination, voluntary activation differed significantly between BFR and CON with greater reductions during BFR. At the early stage of exercise, BFR exacerbated the development of muscle fatigue mainly due to a pronounced impairment in contractile function. Despite the high level of muscle fatigue during BFR exercise, the effect of BFR on muscle fatigue was diminished after 2 min of reperfusion, suggesting that BFR has a strong but short-lasting effect on neuromuscular function.
Banthia, Smriti; Bergner, Daniel W; Chicos, Alexandru B; Ng, Jason; Pelchovitz, Daniel J; Subacius, Haris; Kadish, Alan H; Goldberger, Jeffrey J
2013-01-01
This study investigated autonomic nervous system function in subjects with diabetes during exercise and recovery. Eighteen type 2 diabetics (age 55±2 years) and twenty healthy controls (age 51±1 years) underwent two 16-min bicycle submaximal ECG stress tests followed by 45 min of recovery. During session #2, atropine (0.04 mg/kg) was administered at peak exercise, and the final two minutes of exercise and entire recovery occurred under parasympathetic blockade. Plasma catecholamines were measured throughout. Parasympathetic effect was defined as the difference between a measured parameter at baseline and after parasympathetic blockade. The parasympathetic effect on the RR interval was blunted (P=.004) in diabetic subjects during recovery. Parasympathetic effect on QT-RR slope during early recovery was diminished in the diabetes group (diabetes 0.13±0.02, control 0.21±0.02, P=.03). Subjects with diabetes had a lower heart rate recovery at 1 min (diabetes 18.5±1.9 bpm, control 27.6±1.5 bpm, P<.001). In subjects with well-controlled type 2 diabetes, even with minimal evidence of CAN using current methodology, altered cardiac autonomic balance is present and can be detected through an exercise-based assessment for CAN. The early post-exercise recovery period in diabetes was characterized by enhanced sympathoexcitation, diminished parasympathetic reactivation and delay in heart rate recovery. Copyright © 2013 Elsevier Inc. All rights reserved.
The impact of obesity on pentraxin 3 and inflammatory milieu to acute aerobic exercise.
Slusher, Aaron L; Mock, J Thomas; Whitehurst, Michael; Maharaj, Arun; Huang, Chun-Jung
2015-02-01
Pentraxin 3 (PTX3) has recently been linked to obesity-associated inflammation, serving as a cardioprotective modulator against cardiovascular disease (CVD). Aerobic exercise has been shown to enhance plasma PTX3 levels; however, the impact of obesity on PTX3 response to exercise remains unknown. Therefore, this study sought to examine whether obese subjects would have an attenuated plasma PTX3 response compared to normal-weight subjects following acute aerobic exercise. The relationship of plasma PTX3 with pro-inflammatory cytokines (IL-6 and TNF-α) was also examined. Twenty healthy subjects (10 obese [4 males and 6 females] and 10 normal-weight [4 males, 6 females]) performed 30min of continuous submaximal aerobic exercise. At baseline, obese subjects exhibited approximately 40% lower plasma PTX3 and a 7-fold greater IL-6 concentration compared to normal-weight subjects. In response to exercise, no difference was observed in PTX3 or IL-6 as indicated by area-under-the-curve "with respect to increase" (AUCi) analyses. Furthermore, PTX3 AUCi was positively correlated with cardiorespiratory fitness levels (VO(2max)) (r=0.594, p=0.006), even after controlling for body mass index. These findings suggest that in addition to obesity-associated complications, low cardiorespiratory fitness levels could impact exercise-induced PTX3 elevations, thereby potentially diminishing PTX3's effects of anti-inflammation and/or cardioprotection. Copyright © 2015 Elsevier Inc. All rights reserved.
Lui, Mikaela A.; Mahalingam, Sajeni; Patel, Paras; Connaty, Alex D.; Ivy, Catherine M.; Cheviron, Zachary A.; Storz, Jay F.; McClelland, Grant B.
2015-01-01
The hypoxic and cold environment at high altitudes requires that small mammals sustain high rates of O2 transport for exercise and thermogenesis while facing a diminished O2 availability. We used laboratory-born and -raised deer mice (Peromyscus maniculatus) from highland and lowland populations to determine the interactive effects of ancestry and hypoxia acclimation on exercise performance. Maximal O2 consumption (V̇o2max) during exercise in hypoxia increased after hypoxia acclimation (equivalent to the hypoxia at ∼4,300 m elevation for 6–8 wk) and was consistently greater in highlanders than in lowlanders. V̇o2max during exercise in normoxia was not affected by ancestry or acclimation. Highlanders also had consistently greater capillarity, oxidative fiber density, and maximal activities of oxidative enzymes (cytochrome c oxidase and citrate synthase) in the gastrocnemius muscle, lower lactate dehydrogenase activity in the gastrocnemius, and greater cytochrome c oxidase activity in the diaphragm. Hypoxia acclimation did not affect any of these muscle traits. The unique gastrocnemius phenotype of highlanders was associated with higher mRNA and protein abundances of peroxisome proliferator-activated receptor γ (PPARγ). Vascular endothelial growth factor (VEGFA) transcript abundance was lower in highlanders, and hypoxia acclimation reduced the expression of numerous genes that regulate angiogenesis and energy metabolism, in contrast to the observed population differences in muscle phenotype. Lowlanders exhibited greater increases in blood hemoglobin content, hematocrit, and wet lung mass (but not dry lung mass) than highlanders after hypoxia acclimation. Genotypic adaptation to high altitude, therefore, improves exercise performance in hypoxia by mechanisms that are at least partially distinct from those underlying hypoxia acclimation. PMID:25695288
Mokhtari-Zaer, Amin; Ghodrati-Jaldbakhan, Shahrbanoo; Vafaei, Abbas Ali; Miladi-Gorji, Hossein; Akhavan, Maziar M; Bandegi, Ahmad Reza; Rashidy-Pour, Ali
2014-09-01
Chronic exposure to morphine results in cognitive deficits and alterations of apoptotic proteins in favor of cell death in the hippocampus, a brain region critically involved in learning and memory. Physical activity has been shown to have beneficial effects on brain health. In the current work, we examined the effects of voluntary and treadmill exercise on spontaneous withdrawal signs, the associated cognitive defects, and changes of apoptotic proteins in morphine-dependent rats. Morphine dependence was induced through bi-daily administrations of morphine (10mg/kg) for 10 days. Then, the rats were trained under two different exercise protocols: mild treadmill exercise or voluntary wheel exercise for 10 days. After exercise training, their spatial learning and memory and aversive memory were examined by a water maze and by an inhibitory avoidance task, respectively. The expression of the pro-apoptotic protein Bax and the anti-apoptotic protein Bcl-2 in the hippocampus were determined by immunoblotting. We found that chronic exposure to morphine impaired spatial and aversive memory and remarkably suppressed the expression of Bcl-2, but Bax expression remained constant. Both voluntary and treadmill exercise alleviated memory impairment, increased the expression of Bcl-2 protein, and only the later suppressed the expression of Bax protein in morphine-dependent animals. Moreover, both exercise protocols diminished the occurrence of spontaneous morphine withdrawal signs. Our findings showed that exercise reduces the spontaneous morphine-withdrawal signs, blocks the associated impairment of cognitive performance, and overcomes morphine-induced alterations in apoptotic proteins in favor of cell death. Thus, exercise may be a useful therapeutic strategy for cognitive and behavioral deficits in addict individuals. Copyright © 2014 Elsevier B.V. All rights reserved.
Blasco-Lafarga, Cristina; Martínez-Navarro, Ignacio; Mateo-March, Manuel
2013-01-01
Little research exists concerning Heart Rate (HR) Variability (HRV) following supramaximal efforts focused on upper-body explosive strength-endurance. Since they may be very demanding, it seems of interest to analyse the relationship among performance, lactate and HR dynamics (i.e. HR, HRV and complexity) following them; as well as to know how baseline cardiac autonomic modulation mediates these relationships. The present study aimed to analyse associations between baseline and post-exercise HR dynamics following a supramaximal Judo test, and their relationship with lactate, in a sample of 22 highly-trained male judoists (20.70±4.56 years). A large association between the increase in HR from resting to exercise condition and performance suggests that individuals exerted a greater sympathetic response to achieve a better performance (Rating of Perceived Exertion: 20; post-exercise peak lactate: 11.57±2.24 mmol/L; 95.76±4.13 % of age-predicted HRmax). Athletes with higher vagal modulation and lower sympathetic modulation at rest achieved both a significant larger ∆HR and a faster post-exercise lactate removal. A enhanced resting parasympathetic modulation might be therefore related to a further usage of autonomic resources and a better immediate metabolic recovery during supramaximal exertions. Furthermore, analyses of variance displayed a persistent increase in α1 and a decrease in lnRMSSD along the 15 min of recovery, which are indicative of a diminished vagal modulation together with a sympathovagal balance leaning to sympathetic domination. Eventually, time-domain indices (lnRMSSD) showed no lactate correlations, while nonlinear indices (α1 and lnSaEn) appeared to be moderate to strongly correlated with it, thus pointing to shared mechanisms between neuroautonomic and metabolic regulation. PMID:24205273
2013-01-01
Background Reaction time, coordination, and cognition performance typically diminish in older adults, which may lead to gait impairments, falls, and injuries. Regular strength–balance exercises are highly recommended to reduce this problem and to improve health, well-being, and independence in old age. However, many older people face a lack of motivation in addition to other strong barriers to exercise. We developed ActiveLifestyle, an information technology (IT)-based system for active and healthy aging aiming at improving balance and strength. ActiveLifestyle is a training app that runs on a tablet and assists, monitors, and motivates older people to follow personalized training plans autonomously at home. Objective The objectives were to (1) investigate which IT-mediated motivation strategies increase adherence to physical exercise training plans in older people, (2) assess the impact of ActiveLifestyle on physical activity behavior change, and (3) demonstrate the effectiveness of the ActiveLifestyle training to improve gait speed. Methods A total of 44 older adults followed personalized, 12-week strength and balance training plans. All participants performed the exercises autonomously at home. Questionnaires were used to assess the technological familiarity and stage of behavior change, as well as the effectiveness of the motivation instruments adopted by ActiveLifestyle. Adherence to the exercise plan was evaluated using performance data collected by the app and through information given by the participants during the study. Pretests and posttests were performed to evaluate gait speed of the participants before and after the study. Results Participants were 75 years (SD 6), predominantly female (64%), held a trade or professional diploma (54%), and their past profession was in a sitting position (43%). Of the 44 participants who enrolled, 33 (75%) completed the study. The app proved to assist and motivate independently living and healthy older adults to autonomously perform strength–balance exercises (median 6 on a 7-point Likert scale). Social motivation strategies proved more effective than individual strategies to stimulate the participants to comply with the training plan, as well as to change their behavior permanently toward a more physically active lifestyle. The exercises were effective to improve preferred and fast gait speed. Conclusions ActiveLifestyle assisted and motivated independently living and healthy older people to autonomously perform strength–balance exercises over 12 weeks and had low dropout rates. The social motivation strategies were more effective to stimulate the participants to comply with the training plan and remain on the intervention. The adoption of assistive technology devices for physical intervention tends to motivate and retain older people exercising for longer periods of time. PMID:23939401
Silveira, Patrícia; van de Langenberg, Rolf; van Het Reve, Eva; Daniel, Florian; Casati, Fabio; de Bruin, Eling D
2013-08-12
Reaction time, coordination, and cognition performance typically diminish in older adults, which may lead to gait impairments, falls, and injuries. Regular strength-balance exercises are highly recommended to reduce this problem and to improve health, well-being, and independence in old age. However, many older people face a lack of motivation in addition to other strong barriers to exercise. We developed ActiveLifestyle, an information technology (IT)-based system for active and healthy aging aiming at improving balance and strength. ActiveLifestyle is a training app that runs on a tablet and assists, monitors, and motivates older people to follow personalized training plans autonomously at home. The objectives were to (1) investigate which IT-mediated motivation strategies increase adherence to physical exercise training plans in older people, (2) assess the impact of ActiveLifestyle on physical activity behavior change, and (3) demonstrate the effectiveness of the ActiveLifestyle training to improve gait speed. A total of 44 older adults followed personalized, 12-week strength and balance training plans. All participants performed the exercises autonomously at home. Questionnaires were used to assess the technological familiarity and stage of behavior change, as well as the effectiveness of the motivation instruments adopted by ActiveLifestyle. Adherence to the exercise plan was evaluated using performance data collected by the app and through information given by the participants during the study. Pretests and posttests were performed to evaluate gait speed of the participants before and after the study. Participants were 75 years (SD 6), predominantly female (64%), held a trade or professional diploma (54%), and their past profession was in a sitting position (43%). Of the 44 participants who enrolled, 33 (75%) completed the study. The app proved to assist and motivate independently living and healthy older adults to autonomously perform strength-balance exercises (median 6 on a 7-point Likert scale). Social motivation strategies proved more effective than individual strategies to stimulate the participants to comply with the training plan, as well as to change their behavior permanently toward a more physically active lifestyle. The exercises were effective to improve preferred and fast gait speed. ActiveLifestyle assisted and motivated independently living and healthy older people to autonomously perform strength-balance exercises over 12 weeks and had low dropout rates. The social motivation strategies were more effective to stimulate the participants to comply with the training plan and remain on the intervention. The adoption of assistive technology devices for physical intervention tends to motivate and retain older people exercising for longer periods of time.
Fournier, Sara B.; Reger, Brian L.; Donley, David A.; Bonner, Daniel E.; Warden, Bradford E.; Gharib, Wissam; Failinger, Conard F.; Olfert, Melissa D.; Frisbee, Jefferson C.; Olfert, I. Mark; Chantler, Paul D.
2013-01-01
MetS is the manifestation of a cluster of cardiovascular (CV) risk factors and is associated with a three-fold increase risk of CV morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to comprehensively examine LV and arterial responses to exercise in MetS individuals without diabetes and/or overt CVD compared to a healthy control population. CV function was characterized using Doppler echocardiography and gas exchange in MetS (n=27) vs. healthy controls (n=20) at rest and during peak exercise. At rest, MetS individuals displayed normal LV systolic function but reduced LV diastolic function vs. healthy controls. During peak exercise, individuals with MetS had impaired contractility; pump performance, and vasodilator reserve capacity vs. controls. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in MetS vs. controls. These findings possess clinical importance as they provide insight to the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of CV morbidity and mortality. PMID:24036595
Interactive processes link the multiple symptoms of fatigue in sport competition.
Knicker, Axel J; Renshaw, Ian; Oldham, Anthony R H; Cairns, Simeon P
2011-04-01
Muscle physiologists often describe fatigue simply as a decline of muscle force and infer this causes an athlete to slow down. In contrast, exercise scientists describe fatigue during sport competition more holistically as an exercise-induced impairment of performance. The aim of this review is to reconcile the different views by evaluating the many performance symptoms/measures and mechanisms of fatigue. We describe how fatigue is assessed with muscle, exercise or competition performance measures. Muscle performance (single muscle test measures) declines due to peripheral fatigue (reduced muscle cell force) and/or central fatigue (reduced motor drive from the CNS). Peak muscle force seldom falls by >30% during sport but is often exacerbated during electrical stimulation and laboratory exercise tasks. Exercise performance (whole-body exercise test measures) reveals impaired physical/technical abilities and subjective fatigue sensations. Exercise intensity is initially sustained by recruitment of new motor units and help from synergistic muscles before it declines. Technique/motor skill execution deviates as exercise proceeds to maintain outcomes before they deteriorate, e.g. reduced accuracy or velocity. The sensation of fatigue incorporates an elevated rating of perceived exertion (RPE) during submaximal tasks, due to a combination of peripheral and higher CNS inputs. Competition performance (sport symptoms) is affected more by decision-making and psychological aspects, since there are opponents and a greater importance on the result. Laboratory based decision making is generally faster or unimpaired. Motivation, self-efficacy and anxiety can change during exercise to modify RPE and, hence, alter physical performance. Symptoms of fatigue during racing, team-game or racquet sports are largely anecdotal, but sometimes assessed with time-motion analysis. Fatigue during brief all-out racing is described biomechanically as a decline of peak velocity, along with altered kinematic components. Longer sport events involve pacing strategies, central and peripheral fatigue contributions and elevated RPE. During match play, the work rate can decline late in a match (or tournament) and/or transiently after intense exercise bursts. Repeated sprint ability, agility and leg strength become slightly impaired. Technique outcomes, such as velocity and accuracy for throwing, passing, hitting and kicking, can deteriorate. Physical and subjective changes are both less severe in real rather than simulated sport activities. Little objective evidence exists to support exercise-induced mental lapses during sport. A model depicting mind-body interactions during sport competition shows that the RPE centre-motor cortex-working muscle sequence drives overall performance levels and, hence, fatigue symptoms. The sporting outputs from this sequence can be modulated by interactions with muscle afferent and circulatory feedback, psychological and decision-making inputs. Importantly, compensatory processes exist at many levels to protect against performance decrements. Small changes of putative fatigue factors can also be protective. We show that individual fatigue factors including diminished carbohydrate availability, elevated serotonin, hypoxia, acidosis, hyperkalaemia, hyperthermia, dehydration and reactive oxygen species, each contribute to several fatigue symptoms. Thus, multiple symptoms of fatigue can occur simultaneously and the underlying mechanisms overlap and interact. Based on this understanding, we reinforce the proposal that fatigue is best described globally as an exercise-induced decline of performance as this is inclusive of all viewpoints. © 2011 Adis Data Information BV. All rights reserved.
Urhausen, A; Gabriel, H H; Weiler, B; Kindermann, W
1998-02-01
In the present prospective longitudinal study 17 male endurance trained athletes (cyclists and triathletes; age 23.4+/-6.7 years, VO2max 61.2+/-7.5 ml x min(-1) x kg(-1); means+/-SD) were investigated both during a state of overtraining syndrome (OT: N=15), mainly induced by an increase of exercise intensity, as well as several times in a state of regular physical ability (NS: N=62). Cycle-ergometric and psychological data were compared for a period of approximately 19 months. On 2 separate days, each subject performed a maximum incremental graded exercise, two anaerobic tests (10 s and 30 s) as well as a short-endurance "stress test" with the intensity of 110% of the individual anaerobic threshold until volitional exhaustion. The mood state was recorded by a psychological questionnaire including 40 basic items. During OT the submaximal lactate concentrations were slightly decreased. The performance of the 10 s- and 30 s-tests was unaffected. In contrast, the duration of the "stress test" decreased significantly by approximately 27% during OT compared to the individual NS. The submaximal oxygen uptake measured during the incremental graded exercise was slightly higher during OT as compared to NS, whereas the submaximal and maximal respiratory exchange ratio, maximal heart rate and maximal lactate concentrations were decreased. At the 10th minute of the "stress test", ammonia tended to be increased during OT (P=0.048). The parameters of mood state at rest as well as the subjective rating of perceived exertion during exercise were significantly impaired during OT. In conclusion, the results indicate a decreased intramuscular utilization of carbohydrates with diminished maximal anaerobic lactacid energy supply during OT. Neither the lactate-performance relationship during incremental graded exercise nor the anaerobic alactacid performance showed alterations. The duration of the short-endurance "stress test", the maximal lactate concentration of the incremental graded exercise as well as the altered mood profile turned out to be the most sensitive parameters for the diagnosis of OT.
Aging process alters hippocampal and cortical secretase activities of Wistar rats.
Bertoldi, Karine; Cechinel, Laura Reck; Schallenberger, Bruna; Meireles, Louisiana; Basso, Carla; Lovatel, Gisele Agustini; Bernardi, Lisiane; Lamers, Marcelo Lazzaron; Siqueira, Ionara Rodrigues
2017-01-15
A growing body of evidence has demonstrated amyloid plaques in aged brain; however, little attention has been given to amyloid precursor protein (APP) processing machinery during the healthy aging process. The amyloidogenic and non-amyloidogenic pathways, represented respectively by β- and α-secretases (BACE and TACE), are responsible for APP cleavage. Our working hypothesis is that the normal aging process could imbalance amyloidogenic and non-amyloidogenic pathways specifically BACE and TACE activities. Besides, although it has been showed that exercise can modulate secretase activities in Alzheimer Disease models the relationship between exercise effects and APP processing during healthy aging process is rarely studied. Our aim was to investigate the aging process and the exercise effects on cortical and hippocampal BACE and TACE activities and aversive memory performance. Young adult and aged Wistar rats were subjected to an exercise protocol (20min/day for 2 weeks) and to inhibitory avoidance task. Biochemical parameters were evaluated 1h and 18h after the last exercise session in order to verify transitory and delayed exercise effects. Aged rats exhibited impaired aversive memory and diminished cortical TACE activity. Moreover, an imbalance between TACE and BACE activities in favor of BACE activity was observed in aged brain. Moderate treadmill exercise was unable to alter secretase activities in any brain areas or time points evaluated. Our results suggest that aging-related aversive memory decline is partly linked to decreased cortical TACE activity. Additionally, an imbalance between secretase activities can be related to the higher vulnerability to neurodegenerative diseases induced by aging. Copyright © 2016 Elsevier B.V. All rights reserved.
A study of ventricular contractility and other parameters possibly related to vasodepressor syncope
NASA Technical Reports Server (NTRS)
Hyatt, K. H.; Sullivan, R. W.; Spears, W. R.; Vetter, W. R.
1973-01-01
The effects of diminished orthostatic and exercise tolerance resulting from prolonged bedrest were studied by noninvasion methods to determine if alterations in myocardial contractility were induced by bedrest. These methods were apexcardiography, systolic time intervals, and echocardiography. It is concluded that bedrest causes detrimental alterations in the contractile state of the myocardium which accounts for the decreases in maximal oxygen uptaken during exercise after bedrest. Tabulated test data are included.
Aerobic physical exercise for adult patients with haematological malignancies.
Bergenthal, Nils; Will, Andrea; Streckmann, Fiona; Wolkewitz, Klaus-Dieter; Monsef, Ina; Engert, Andreas; Elter, Thomas; Skoetz, Nicole
2014-11-11
Although people with haematological malignancies have to endure long phases of therapy and immobility which is known to diminish their physical performance level, the advice to rest and avoid intensive exercises is still common practice. This recommendation is partly due to the severe anaemia and thrombocytopenia from which many patients suffer. The inability to perform activities of daily living restricts them, diminishes their quality of life and can influence medical therapy. To evaluate the efficacy, safety and feasibility of aerobic physical exercise for adults suffering from haematological malignancies. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2014, Issue 1) and MEDLINE (1950 to January 2014) as well as conference proceedings for randomised controlled trials (RCTs). We included RCTs comparing an aerobic physical exercise intervention, intending to improve the oxygen system, in addition to standard care with standard care only for adults suffering from haematological malignancies. We also included studies that evaluated aerobic exercise in addition to strength training. We excluded studies that investigated the effect of training programmes that were composed of yoga, tai chi chuan, qigong or similar types of exercise. We also excluded studies exploring the influence of strength training without additive aerobic exercise. Additionally, we excluded studies assessing outcomes without any clinical impact. Two review authors independently screened search results, extracted data and assessed the quality of trials. We used risk ratios (RRs) for adverse events and 100-day survival, standardised mean differences for quality of life (QoL), fatigue, and physical performance, and mean differences for anthropometric measurements. Our search strategies identified 1518 potentially relevant references. Of these, we included nine RCTs involving 818 participants. The potential risk of bias in these trials is unclear, due to poor reporting.The majority of participants suffered from acute lymphoblastic leukaemia (ALL), acute myeloid leukaemia (AML), malignant lymphoma and multiple myeloma, and six trials randomised people receiving stem cell transplantation. Mostly, the exercise intervention consisted of various walking intervention programmes with different duration and intensity levels.Our primary endpoint of overall survival (OS) was not analysed in any of the included trials, but three trials reported deceased participants during the course of the study or during the first 100 days. There is no evidence for a difference between participants exercising and those in the control group (RR 0.93; 95% CI 0.59 to 1.47; P = 0.75; 3 trials, 269 participants, moderate quality of evidence).Four trials analysed the influence of exercise intervention on quality of life (QoL). Excluding one trial with serious baseline imbalances, physical exercise improves QoL (SMD 0.26; 95% CI 0.03 to 0.49; P = 0.03; 3 trials, 291 participants, low quality of evidence). This positive effect of exercise was also found in the subscales physical functioning (SMD 0.33; 95% CI 0.13 to 0.52; P = 0.0009; 4 trials, 422 participants, moderate quality of evidence) and depression (SMD 0.25; 95% CI -0.00 to 0.50; P = 0.05; 3 trials, 249 participants, low quality of evidence). However, there is no evidence for a difference between additional exercise and standard treatment for the subscale anxiety (SMD -0.18; 95% CI -0.64 to 0.28; P = 0.45; 3 trials, 249 participants, low quality of evidence). Seven trials (692 participants) evaluated fatigue. There is moderate quality of evidence that exercise improves fatigue (SMD 0.24; 95% CI 0.08 to 0.40; P = 0.003).Eight studies evaluated various aspects of physical performance (e.g. aerobic capacity, cardiovascular fitness), but none of them could be pooled in a meta-analysis. In seven trials there is a tendency or statistically significant effect favouring the exercise group (very low quality of evidence).Three trials (266 participants) investigated serious adverse events (SAEs) (e.g. bleeding, fever, pneumonia, deep vein thrombosis, and infection), and one trial (122 participants) assessed adverse events (AEs). There is no evidence for a difference between arms in terms of SAEs (RR 1.44; 95% CI 0.96 to 2.18; P = 0.06) or AEs (RR 7.23; 95% CI 0.38 to 137.05; P = 0.19); both findings are based on low quality of evidence. There is no evidence for differences in mortality between the exercise and control groups. Physical exercise added to standard care can improve quality of life, especially physical functioning, depression and fatigue. Currently, there is inconclusive evidence regarding anxiety, physical performance, serious adverse events and adverse events.We need further trials with more participants and longer follow-up periods to evaluate the effects of exercise intervention for people suffering from haematological malignancies. Furthermore, we need trials with overall survival as the primary outcome to determine whether the suggested benefits will translate into a survival advantage. To enhance comparability of study data, development and implementation of core sets of measuring devices would be helpful.
The effects of strength training on cognitive performance in elderly women.
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.
ERIC Educational Resources Information Center
US House of Representatives, 2007
2007-01-01
This hearing discussed how lack of coordination between laboratory exercises and classroom lectures, inadequately trained teachers, languishing facilities, and current high school organization diminish the value these exercises can have or prohibit them all together, and highlighted how a strong hands-on experience can create scientifically…
Scharhag, J; Meyer, T; Görge, G; Kindermann, W
2003-01-24
A 32-year-old competitive soccer player presented with palpitations he had felt for 4 weeks during maximal activity (soccer training and match). The physical examination and an exercise electrocardiogram were carried out by his general practitioner up to 19 s at 350 W and a heart rate of 147/min without showing any abnormalities. All blood parameters revealed no signs of illness. During treadmill exercise at a heart rate of 181/min, a non-sustained ventricular tachycardia was induced. Echocardiography showed a dilated left ventricle with an enddiastolic diameter of 70 mm and low fractional shortening (28 %). Cardiac catheterization demonstrated a diminished left ventricular ejection fraction (38 %) and an enlarged enddiastolic volume (199 ml) without signs of coronary artery disease. Electrophysiologic testing induced a non-sustained ventricular tachycardia. The echocardiographic and angiographic results indicated a dilated cardiomyopathy. Competitive sports activities were stopped and treatment with a beta-blocker (metoprolol) and an ACE-antagonist (ramipril) was started. In young male and female athletes, the possibility of severe cardiac abnormalities have to be considered even in the presence of good physical fitness and performance. To reach a high sensitivity for diagnostic ergometry, the work-load must reach the maximal capacity of the cardio-pulmonary system. Differences in the exercise performance of athletes and untrained subjects have to be considered.
Dobashi, Kohei; Fujii, Naoto; Watanabe, Kazuhito; Tsuji, Bun; Sasaki, Yosuke; Fujimoto, Tomomi; Tanigawa, Satoru; Nishiyasu, Takeshi
2017-08-01
To investigate the effect of voluntary hypocapnic hyperventilation or moderate hypoxia on metabolic and heart rate responses during high-intensity intermittent exercise. Ten males performed three 30-s bouts of high-intensity cycling [Ex1 and Ex2: constant-workload at 80% of the power output in the Wingate anaerobic test (WAnT), Ex3: WAnT] interspaced with 4-min recovery periods under normoxic (Control), hypocapnic or hypoxic (2500 m) conditions. Hypocapnia was developed through voluntary hyperventilation for 20 min prior to Ex1 and during each recovery period. End-tidal CO 2 pressure was lower before each exercise in the hypocapnia than control trials. Oxygen uptake ([Formula: see text]) was lower in the hypocapnia than control trials (822 ± 235 vs. 1645 ± 245 mL min -1 ; mean ± SD) during Ex1, but not Ex2 or Ex3, without a between-trial difference in the power output during the exercises. Heart rates (HRs) during Ex1 (127 ± 8 vs. 142 ± 10 beats min -1 ) and subsequent post-exercise recovery periods were lower in the hypocapnia than control trials, without differences during or after Ex2, except at 4 min into the second recovery period. [Formula: see text] did not differ between the control and hypoxia trials throughout. These results suggest that during three 30-s bouts of high-intensity intermittent cycling, (1) hypocapnia reduces the aerobic metabolic rate with a compensatory increase in the anaerobic metabolic rate during the first but not subsequent exercises; (2) HRs during the exercise and post-exercise recovery periods are lowered by hypocapnia, but this effect is diminished with repeated exercise bouts, and (3) moderate hypoxia (2500 m) does not affect the metabolic response during exercise.
Fournier, Sara B; Reger, Brian L; Donley, David A; Bonner, Daniel E; Warden, Bradford E; Gharib, Wissam; Failinger, Conard F; Olfert, Melissa D; Frisbee, Jefferson C; Olfert, I Mark; Chantler, Paul D
2014-01-01
Metabolic syndrome (MetS) is the manifestation of a cluster of cardiovascular risk factors and is associated with a threefold increase in the risk of cardiovascular morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to examine comprehensively the LV and arterial responses to exercise in individuals with MetS without diabetes and/or overt cardiovascular disease in comparison to a healthy control population. Cardiovascular function was characterized using Doppler echocardiography and gas exchange in individuals with MetS (n = 27) versus healthy control subjects (n = 20) at rest and during peak exercise. At rest, individuals with MetS displayed normal LV systolic function but reduced LV diastolic function compared with healthy control subjects. During peak exercise, individuals with MetS had impaired contractility, pump performance and vasodilator reserve capacity versus control subjects. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in individuals with MetS versus control subjects. These findings are of clinical importance, because they provide insight into the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of cardiovascular morbidity and mortality.
Training Performed Above Lactate Threshold Decreases p53 and Shelterin Expression in Mice.
de Carvalho Cunha, Verusca Najara; Dos Santos Rosa, Thiago; Sales, Marcelo Magalhães; Sousa, Caio Victor; da Silva Aguiar, Samuel; Deus, Lysleine Alves; Simoes, Herbert Gustavo; de Andrade, Rosangela Vieira
2018-06-26
Telomere shortening is associated to sarcopenia leading to functional impairment during aging. There are mechanisms associated with telomere attrition, as well to its protection and repair. Physical training is a factor that attenuates telomere shortening, but little is known about the effects of different exercise intensities on telomere biology. Thus, we evaluated the effects of exercise intensity (moderate vs. high-intensity domain) on gene expression of senescence markers Checkpoint kinase 2 and tumor suppressor ( Chk2 and p53 , respectively), shelterin telomere repeat binding 1 and 2 ( Trf1 / Trf2 ), DNA repair ( Xrcc5 ), telomerase reverse transcriptase ( mTERT ) and telomere length in middle aged mice. Three groups were studied: a control group (CTL) and two groups submitted to swimming at intensities below the lactate threshold (LI group) and above the lactate threshold (HI group) for 40 and 20 min respectively, for 12 weeks. After training, the HI group showed reduction in p53 expression in the muscle, and decreased shelterin complex expression when compared to LI group. No differences were observed between groups for mTERT expression and telomere length. Thus, exercise training in high-intensity domain was more effective on reducing markers of senescence and apoptosis. The higher intensity exercise training also diminished shelterin expression, with no differences in telomere length and mTERT expression. Such results possibly indicate a more effective DNA protection for the higher-intensity exercise training. © Georg Thieme Verlag KG Stuttgart · New York.
Ooue, Anna; Sato, Kohei; Hirasawa, Ai; Sadamoto, Tomoko
2012-11-07
The superficial vein of the resting limb constricts sympathetically during exercise. Central command is the one of the neural mechanisms that controls the cardiovascular response to exercise. However, it is not clear whether central command contributes to venous vessel response during exercise. Tendon vibration during static elbow flexion causes primary muscle spindle afferents, such that a lower central command is required to achieve a given force without altering muscle force. The purpose of this study was therefore to investigate whether a reduction in central command during static exercise with tendon vibration influences the superficial venous vessel response in the resting limb. Eleven subjects performed static elbow flexion at 35% of maximal voluntary contraction with (EX + VIB) and without (EX) vibration of the biceps brachii tendon. The heart rate, mean arterial pressure, and rating of perceived exertion (RPE) in overall and exercising muscle were measured. The cross-sectional area (CSAvein) and blood velocity of the basilic vein in the resting upper arm were assessed by ultrasound, and blood flow (BFvein) was calculated using both variables. Muscle tension during exercise was similar between EX and EX + VIB. However, RPEs at EX + VIB were lower than those at EX (P <0.05). Increases in heart rate and mean arterial pressure during exercise at EX + VIB were also lower than those at EX (P <0.05). CSAvein in the resting limb at EX decreased during exercise from baseline (P <0.05), but CSAvein at EX + VIB did not change during exercise. CSAvein during exercise at EX was smaller than that at EX + VIB (P <0.05). However, BFvein did not change during the protocol under either condition. The decreases in circulatory response and RPEs during EX + VIB, despite identical muscle tension, showed that activation of central command was less during EX + VIB than during EX. Abolishment of the decrease in CSAvein during exercise at EX + VIB may thus have been caused by a lower level of central command at EX + VIB rather than EX. Diminished central command induced by tendon vibration may attenuate the superficial venous vessel response of the resting limb during sustained static arm exercise.
Oxidative stress does not influence local sweat rate during high-intensity exercise.
Meade, Robert D; Fujii, Naoto; Poirier, Martin P; Boulay, Pierre; Sigal, Ronald J; Kenny, Glen P
2018-02-01
What is the central question of this study? We evaluated whether oxidative stress attenuates the contribution of nitric oxide to sweating during high-intensity exercise. What is the main finding and its importance? In contrast to our previous report of an oxidative stress-mediated reduction in nitric oxide-dependent cutaneous vasodilatation in this cohort during intense exercise, we demonstrated no influence of local ascorbate administration on the sweating response during moderate- (∼51% peak oxygen uptake) or high-intensity exercise (∼72% peak oxygen uptake). These new findings provide important mechanistic insight into how exercise-induced oxidative stress impacts sudomotor activity. Nitric oxide (NO)-dependent sweating is diminished during high- but not moderate-intensity exercise. We evaluated whether this impairment stems from increased oxidative stress during high-intensity exercise. On two separate days, 11 young (24 ± 4 years) men cycled in the heat (35°C) at a moderate [500 W; 52 ± 6% peak oxygen uptake (V̇O2 peak )] or high (700 W; 71 ± 5% V̇O2 peak ) rate of metabolic heat production. Each session included two 30 min exercise bouts separated by a 20 min recovery period. Local sweat rate was monitored at four forearm skin sites continuously perfused via intradermal microdialysis with the following: (i) lactated Ringer solution (Control); (ii) 10 mm ascorbate (Ascorbate; non-selective antioxidant); (iii) 10 mm N G -nitro-l-arginine methyl ester (l-NAME; NO synthase inhibitor); or (iv) 10 mm ascorbate plus 10 mm l-NAME (Ascorbate + l-NAME). During moderate exercise, sweat rate was attenuated at the l-NAME and Ascorbate + l-NAME sites (both ∼1.0 mg min -1 cm -2 ; all P < 0.05) but not at the Ascorbate site (∼1.1 mg min -1 cm -2 ; both P ≥ 0.28) in comparison to the Control site (∼1.1 mg min -1 cm -2 ). However, no differences were observed between treatment sites (∼1.4 mg min -1 cm -2 ; P = 0.75) during high-intensity exercise. We conclude that diminished NO-dependent sweating during intense exercise occurs independent of oxidative stress. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.
Fujii, Naoto; Tsuchiya, Sho-Ichiro; Tsuji, Bun; Watanabe, Kazuhito; Sasaki, Yosuke; Nishiyasu, Takeshi
2015-09-01
We evaluated whether hypocapnia achieved through voluntary hyperventilation diminishes the increases in oxygen uptake elicited by short-term (e.g., ~30 s) all-out exercise without affecting exercise performance. Nine subjects performed 30-s Wingate anaerobic tests (WAnT) in control and hypocapnia trials on separate days in a counterbalanced manner. During the 20-min rest prior to the 30-s WAnT, the subjects in the hypocapnia trial performed voluntary hyperventilation (minute ventilation = 31 L min(-1)), while the subjects in the control trial continued breathing spontaneously (minute ventilation = 14 L min(-1)). The hyperventilation in the hypocapnia trial reduced end-tidal CO2 pressure from 34.8 ± 2.5 mmHg at baseline rest to 19.3 ± 1.0 mmHg immediately before the 30-s WAnT. In the control trial, end-tidal CO2 pressure at baseline rest (35.9 ± 2.5 mmHg) did not differ from that measured immediately before the 30-s WAnT (35.9 ± 3.3 mmHg). Oxygen uptake during the 30-s WAnT was lower in the hypocapnia than the control trial (1.55 ± 0.52 vs. 1.95 ± 0.44 L min(-1)), while the postexercise peak blood lactate concentration was higher in the hypocapnia than control trial (10.4 ± 1.9 vs. 9.6 ± 1.9 mmol L(-1)). In contrast, there was no difference in the 5-s peak (842 ± 111 vs. 850 ± 107 W) or mean (626 ± 74 vs. 639 ± 80 W) power achieved during the 30-s WAnT between the control and hypocapnia trials. These results suggest that during short-period all-out exercise (e.g., 30-s WAnT), hypocapnia induced by voluntary hyperventilation reduces the aerobic metabolic rate without affecting exercise performance. This implies a compensatory elevation in the anaerobic metabolic rate.
Fujii, Naoto; Meade, Robert D.; Alexander, Lacy M.; Akbari, Pegah; Foudil-bey, Imane; Louie, Jeffrey C.; Boulay, Pierre
2015-01-01
Nitric oxide synthase (NOS) contributes to sweating and cutaneous vasodilation during exercise in younger adults. We hypothesized that endothelial NOS (eNOS) and neuronal NOS (nNOS) mediate NOS-dependent sweating, whereas eNOS induces NOS-dependent cutaneous vasodilation in younger adults exercising in the heat. Further, aging may upregulate inducible NOS (iNOS), which may attenuate sweating and cutaneous vasodilator responses. We hypothesized that iNOS inhibition would augment sweating and cutaneous vasodilation in exercising older adults. Physically active younger (n = 12, 23 ± 4 yr) and older (n = 12, 60 ± 6 yr) adults performed two 30-min bouts of cycling at a fixed rate of metabolic heat production (400 W) in the heat (35°C). Sweat rate and cutaneous vascular conductance (CVC) were evaluated at four intradermal microdialysis sites with: 1) lactated Ringer (control), 2) nNOS inhibitor (nNOS-I, NPLA), 3) iNOS inhibitor (iNOS-I, 1400W), or 4) eNOS inhibitor (eNOS-I, LNAA). In younger adults during both exercise bouts, all inhibitors decreased sweating relative to control, albeit a lower sweat rate was observed at iNOS-I compared with eNOS-I and nNOS-I sites (all P < 0.05). CVC at the eNOS-I site was lower than control in younger adults throughout the intermittent exercise protocol (all P < 0.05). In older adults, there were no differences between control and iNOS-I sites for sweating and CVC during both exercise bouts (all P > 0.05). We show that iNOS and eNOS are the main contributors to NOS-dependent sweating and cutaneous vasodilation, respectively, in physically active younger adults exercising in the heat, and that iNOS inhibition does not alter sweating or cutaneous vasodilation in exercising physically active older adults. PMID:26586908
Fujii, Naoto; Meade, Robert D; Alexander, Lacy M; Akbari, Pegah; Foudil-Bey, Imane; Louie, Jeffrey C; Boulay, Pierre; Kenny, Glen P
2016-02-01
Nitric oxide synthase (NOS) contributes to sweating and cutaneous vasodilation during exercise in younger adults. We hypothesized that endothelial NOS (eNOS) and neuronal NOS (nNOS) mediate NOS-dependent sweating, whereas eNOS induces NOS-dependent cutaneous vasodilation in younger adults exercising in the heat. Further, aging may upregulate inducible NOS (iNOS), which may attenuate sweating and cutaneous vasodilator responses. We hypothesized that iNOS inhibition would augment sweating and cutaneous vasodilation in exercising older adults. Physically active younger (n = 12, 23 ± 4 yr) and older (n = 12, 60 ± 6 yr) adults performed two 30-min bouts of cycling at a fixed rate of metabolic heat production (400 W) in the heat (35°C). Sweat rate and cutaneous vascular conductance (CVC) were evaluated at four intradermal microdialysis sites with: 1) lactated Ringer (control), 2) nNOS inhibitor (nNOS-I, NPLA), 3) iNOS inhibitor (iNOS-I, 1400W), or 4) eNOS inhibitor (eNOS-I, LNAA). In younger adults during both exercise bouts, all inhibitors decreased sweating relative to control, albeit a lower sweat rate was observed at iNOS-I compared with eNOS-I and nNOS-I sites (all P < 0.05). CVC at the eNOS-I site was lower than control in younger adults throughout the intermittent exercise protocol (all P < 0.05). In older adults, there were no differences between control and iNOS-I sites for sweating and CVC during both exercise bouts (all P > 0.05). We show that iNOS and eNOS are the main contributors to NOS-dependent sweating and cutaneous vasodilation, respectively, in physically active younger adults exercising in the heat, and that iNOS inhibition does not alter sweating or cutaneous vasodilation in exercising physically active older adults. Copyright © 2016 the American Physiological Society.
How to diminish calcium loss and muscle atrophy in space
NASA Astrophysics Data System (ADS)
Gorgolewski, S.
Humans in micro-gravity suffer from Ca loss and muscle atrophy, efforts are made to prevent it by means of physical exercises and with medicaments. The tread-mill and exercise bike are just two most frequently used examples. This can and should be widely extended, and in such a way as to mimic as close as possible the normal loading of the muscles and skeleton which we experience here on the earth. Special very light weight active harness is proposed which monitors the body loading. This is accomplished by means of computer aided monitoring of muscle and bone loading systems. Using feedback it helps the crew to load their bodies and skeletons in the same way as it happens here on the earth. The active exercise mat with pressure sensors first creates a record here on the earth of all normal muscle tensions during exercise. In space the computer guides each exercising crew member to follow their earthbound training routine. High care is needed to select the best and most effective exercises which should demand least energy, yet providing the very best results. May I suggest the very best known to me kind of comprehensive exercises: Yoga. Doing it on the Earth you need next to none special training equipment. Our body is in principle all we need here to do Yoga exercises on the Earth. Integral part of Yoga exercises are abdominal breathing exercises, which can slow down the breathing rate even threefold. This improves the oxygen and CO_2 exchange and massages all internal organs around the clock, helping the adept to stay fit and also keeps their minds steady and calm. Yoga exercises should be mastered already here on the earth, providing the crew with much greater tolerance to micro-gravity. In Yoga we acquire the tolerance not only to zero gravity but also to "negative" gravity: as it happens in all inverted positions. This should help the astronauts to be more tolerant of the half way only step into "zero gravity". Weightlessness state provides us the ultimate in perfect relaxation when asleep or awake. We have to check in space if we can thus diminish the use of medicaments or even eliminate them. Slow Yoga exercises decrease also the amount on food required because life is not so energy demanding in space as it is here under the earth's gravitation. We can stay lean and healthy with such static yet most effective physical exercises. In addition it gives us for free a vegetarian life style, just another benefit so useful in space travel.
The influence of maternal condition on offspring performance in sockeye salmon Oncorhynchus nerka.
Tierney, K B; Patterson, D A; Kennedy, C J
2009-10-01
Eggs were taken from adult sockeye salmon Oncorhynchus nerka that had reached their journey's end in spawn-ready and moribund condition, and fertilized by healthy males. Egg number, size, hatching success and offspring growth did not differ with maternal condition, which suggests the absence of any persisting physiological maternal effects. Differences were noted in the swimming behaviour and physiology of the offspring at parr stage. In a 30 min schooling test conducted using groups of five in a flume, parr from moribund females were more likely to fatigue, were not as tightly schooled, and had a diminished startle response, both in the per cent responding and the burst distance. In individual, confined swimming tests conducted within a tube, post-exercise plasma lactate concentration, which is an indicator of white muscle use, was greater for parr from moribund adult females. The moribund females also had elevated lactate following exercise (their migration), which suggests heritable differences may exist in muscle use. This study shows that juvenile O. nerka artificially propagated from females exhausted by their return migration can exhibit swimming performance differences, indicating that maternal condition may need to be considered in breeding programmes.
Carnitine Acetyltransferase Mitigates Metabolic Inertia and Muscle Fatigue during Exercise.
Seiler, Sarah E; Koves, Timothy R; Gooding, Jessica R; Wong, Kari E; Stevens, Robert D; Ilkayeva, Olga R; Wittmann, April H; DeBalsi, Karen L; Davies, Michael N; Lindeboom, Lucas; Schrauwen, Patrick; Schrauwen-Hinderling, Vera B; Muoio, Deborah M
2015-07-07
Acylcarnitine metabolites have gained attention as biomarkers of nutrient stress, but their physiological relevance and metabolic purpose remain poorly understood. Short-chain carnitine conjugates, including acetylcarnitine, derive from their corresponding acyl-CoA precursors via the action of carnitine acetyltransferase (CrAT), a bidirectional mitochondrial matrix enzyme. We show here that contractile activity reverses acetylcarnitine flux in muscle, from net production and efflux at rest to net uptake and consumption during exercise. Disruption of this switch in mice with muscle-specific CrAT deficiency resulted in acetyl-CoA deficit, perturbed energy charge, and diminished exercise tolerance, whereas acetylcarnitine supplementation produced opposite outcomes in a CrAT-dependent manner. Likewise, in exercise-trained compared to untrained humans, post-exercise phosphocreatine recovery rates were positively associated with CrAT activity and coincided with dramatic shifts in muscle acetylcarnitine dynamics. These findings show acetylcarnitine serves as a critical acetyl buffer for working muscles and provide insight into potential therapeutic strategies for combatting exercise intolerance. Copyright © 2015 Elsevier Inc. All rights reserved.
Revisiting the Debate: Does Exercise Build Strong Bones in the Mature and Senescent Skeleton?
Hughes, Julie M.; Charkoudian, Nisha; Barnes, Jill N.; Morgan, Barbara J.
2016-01-01
Traditional exercise programs seem to be less osteogenic in the mature and post-mature skeleton compared to the young skeleton. This is likely because of the decline in sensitivity of bone to mechanical loading that occurs with advancing age. Another factor contributing to the apparently diminished benefit of exercise in older adults is failure of widely used measurement techniques (i.e., DXA) to identify changes in 3-dimensional bone structure, which are important determinants of bone strength. Moreover, although hormonal contributors to bone loss in the elderly are well-recognized, the influence of age-related increases in sympathetic nervous system activity, which impacts bone metabolism, is rarely considered. In this Perspective, we cite evidence from animal and human studies demonstrating anabolic effects of exercise on bone across the lifespan and we discuss theoretical considerations for designing exercise regimens to optimize bone health. We conclude with suggestions for future research that should help define the osteogenic potential of exercise in older individuals. PMID:27679578
Hietavala, Enni-Maria; Stout, Jeffrey R; Frassetto, Lynda A; Puurtinen, Risto; Pitkänen, Hannu; Selänne, Harri; Suominen, Harri; Mero, Antti A
2017-12-01
Diet composition influences acid-base status of the body. This may become more relevant as renal functional capacity declines with aging. We examined the effects of low (LD) versus high dietary acid load (HD) on blood acid-base status and exercise performance. Participants included 22 adolescents, 33 young adults (YA), and 33 elderly (EL), who followed a 7-day LD and HD in a randomized order. At the end of both diet periods the subjects performed a cycle ergometer test (3 × 10 min at 35%, 55%, 75%, and (except EL) until exhaustion at 100% of maximal oxygen uptake). At the beginning of and after the diet periods, blood samples were collected at rest and after all workloads. Oxygen uptake, respiratory exchange ratio (RER), and heart rate (HR) were monitored during cycling. In YA and EL, bicarbonate (HCO 3 - ) and base excess (BE) decreased over the HD period, and HCO 3 - , BE, and pH were lower at rest after HD compared with LD. In YA and EL women, HCO 3 - and BE were lower at submaximal workloads after HD compared with LD. In YA women, the maximal workload was 19% shorter and maximal oxygen uptake, RER, and HR were lower after HD compared with LD. Our data uniquely suggests that better renal function is associated with higher availability of bases, which may diminish exercise-induced acidosis and improve maximal aerobic performance. Differences in glomerular filtration rate between the subject groups likely explains the larger effects of dietary acid load in the elderly compared with younger subjects and in women compared with men.
Martínez-Sánchez, Ascensión; Ramos-Campo, Domingo J.; Fernández-Lobato, Bárbara; Rubio-Arias, Jacobo A.; Alacid, Fernando; Aguayo, Encarna
2017-01-01
ABSTRACT Background: Watermelon is a rich natural source of l-citrulline. This non-essential amino acid increases exercise performance. Objective: Evaluate the effect of Fashion watermelon juice enriched in l-citrulline (CWJ) (3.45 g per 500 mL) in physical performance and biochemical markers after a half-marathon race. Design: A randomised, double blind, crossover design where 2 h after drinking 500 mL of CWJ or placebo (PLA, beverage without l-citrulline) amateur male runners performed two half-marathon races. Jump height, heart rate and rating of perceived exertion were evaluated before and after the races. Moreover, muscle soreness and plasma markers of muscle damage and metabolism were evaluated for 72 h after the races. Results: Muscle soreness perception was significantly lower from 24 to 72 h after the race with CWJ beverage. Immediately after the races, runners under CWJ condition showed plasma lactate and glucose concentrations significantly lower and higher lactate dehydrogenase and l-arginine concentration than runners under PLA. A maintenance of jump heights after the races under CWJ supplementation was found, decreasing significantly with PLA. Conclusion: A single Fashion watermelon juice enriched in l-citrulline dose diminished muscle soreness perception from 24 to 72 h after the race and maintained lower concentrations of plasma lactate after an exhausting exercise. PMID:28659740
Diminished Status of Religious Liberty in Public Education: Interpreting Mozert and Smith.
ERIC Educational Resources Information Center
Mawdsley, Ralph D.; Mawdsley, Alice S.
1988-01-01
Reviews contemporary court cases to show that free exercise claims are religious and therefore unenforceable under the Establishment Clause's "Lemon" test prohibiting religious activities in public schools. Discuses inadequacies in judicial perception involving compelling interest, a pattern of anti-theistic decisions, and lesser…
12 CFR 998.3 - Reservation of authority.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOME LOAN BANK DISCLOSURES REGISTRATION OF... do not diminish, or otherwise restrict the ability of the Finance Board to exercise, any and all..., that they carry out their housing finance mission, and that they remain adequately capitalized and able...
Cigarette Taxes, Smoking-and Exercise?
Conway, Karen Smith; Niles, David P
2017-08-01
This research provides the first in-depth analysis of the effect that increased cigarette taxes have on exercise behavior. Smoking may diminish the ability to exercise; individuals may also use exercise to compensate for the harmful health effects of smoking or to avoid gaining weight if they cut back. Our conceptual model highlights these and several other avenues for effect and reveals that the predicted effect of cigarette costs on exercise behavior is theoretically ambiguous. To investigate the relationship empirically, 1994-2012 data from the behavioral risk factor surveillance system are combined with state level cigarette tax rates and other state level variables. Several measures of both smoking and exercise behavior are created and estimated in reduced form models. Our results suggest that both smoking and exercise are reduced by cigarette taxes. However, the effects on exercise may be more complicated as we find that certain groups, such as young adults or those who have recently quit smoking, are affected differently. Our analyses also show that the responsiveness of both smoking and exercise behavior to cigarette costs is much smaller in the 2000s, an era of high-tax increases. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Influence of exercise on nutritional requirements.
Pendergast, D R; Meksawan, K; Limprasertkul, A; Fisher, N M
2011-03-01
There is no consensus on the best diet for exercise, as many variables influence it. We propose an approach that is based on the total energy expenditure of exercise and the specific macro- and micronutrients used. di Prampero quantified the impact of intensity and duration on the energy cost of exercise. This can be used to determine the total energy needs and the balance of fats and carbohydrates (CHO). There are metabolic differences between sedentary and trained persons, thus the total energy intake to prevent overfeeding of sedentary persons and underfeeding athletes is important. During submaximal sustained exercise, fat oxidation (FO) plays an important role. This role is diminished and CHO's role increases as exercise intensity increases. At super-maximal exercise intensities, anaerobic glycolysis dominates. In the case of protein and micronutrients, specific recommendations are required. We propose that for submaximal exercise, the balance of CHO and fat favors fat for longer exercise and CHO for shorter exercise, while always maintaining the minimal requirements of each (CHO: 40% and fat: 30%). A case for higher protein (above 15%) as well as creatine supplementation for resistance exercise has been proposed. One may also consider increasing bicarbonate intake for exercise that relies on anaerobic glycolysis, whereas there appears to be little support for antioxidant supplementation. Insuring minimal levels of substrate will prevent exercise intolerance, while increasing some components may increase exercise tolerance.
Cross-activation and Detraining Effects of Tongue Exercise in Aged Rats
Schaser, Allison J.; Ciucci, Michelle R.; Connor, Nadine P.
2015-01-01
Voice and swallowing deficits can occur with aging. Tongue exercise paired with a swallow may be used to treat swallowing disorders, but may also benefit vocal function due to cross-system activation effects. It is unknown how exercise-based neuroplasticity contributes to behavior and maintenance following treatment. Eighty rats were used to examine behavioral parameters and changes in neurotrophins after tongue exercise paired with a swallow. Tongue forces and ultrasonic vocalizations were recorded before and after training/detraining in young and old rats. Tissue was analyzed for neurotrophin content. Results showed tongue exercise paired with a swallow was associated with increased tongue forces at all ages. Gains diminished after detraining in old rats. Age-related changes in vocalizations, neurotrophin 4 (NT4), and brain derived neurotrophic factor (BDNF) were found. Minimal cross-system activation effects were observed. Neuroplastic benefits were demonstrated with exercise in old rats through behavioral improvements and up-regulation of BDNF in the hypoglossal nucleus. Tongue exercise paired with a swallow should be developed, studied, and optimized in human clinical research to treat swallowing and voice disorders in elderly people. PMID:26477376
Sanabria-Martínez, G; García-Hermoso, A; Poyatos-León, R; Álvarez-Bueno, C; Sánchez-López, M; Martínez-Vizcaíno, V
2015-08-01
It is commonly accepted that pregnancy-related physiological changes (circulatory, respiratory, and locomotor) negatively influence the daily physical activity of pregnant women. The aim of this study is to conduct a meta-analysis of randomised controlled trials (RCTs) for assessing the effectiveness of physical exercise interventions during pregnancy to prevent gestational diabetes mellitus and excessive maternal weight gain. Keywords were used to conduct a computerised search in six databases: Cochrane Library Plus, Science Direct, EMBASE, PubMed, Web of Science, and ClinicalTrials.gov. Healthy pregnant women who were sedentary or had low levels of physical activity were selected for RCTs that included an exercise programme. Two independent reviewers extracted data and assessed the quality of the included studies. Of 4225 articles retrieved, 13 RCTs (2873 pregnant women) met the inclusion criteria. Pooled relative risk (RR) or weighted mean differences (WMDs) (depending on the outcome measure) were calculated using a random-effects model. Overall, physical exercise programmes during pregnancy decreased the risk of gestational diabetes mellitus (RR = 0.69; P = 0.009), particularly when the exercise programme was performed throughout pregnancy (RR = 0.64; P = 0.038). Furthermore, decreases were also observed in maternal weight (WMD = -1.14 kg; 95% CI -1.50 to -0.78; P < 0.001). No serious adverse effects were reported. Structured moderate physical exercise programmes during pregnancy decrease the risk of gestational diabetes mellitus and diminish maternal weight gain, and seem to be safe for the mother and the neonate; however, further studies are needed to establish recommendations. © 2015 Royal College of Obstetricians and Gynaecologists.
Exercise-Induced Changes in Metabolic Resposes to Infection in Trained Rats.
1981-07-20
superimposed on fasting reduced it in sedentary rats (24). Swimming amplified fasting ketosis and diminished infection ketonemia and markedly decreased...Ketone body metabolism in the ketosis of starvation and alloxan diabetes. J. Biol. Chem. 245:4382-4390, 1970. 22. MOSES, L. E. Determination of oxygen
The Power of Outdoor Play and Play in Natural Environments
ERIC Educational Resources Information Center
Kemple, Kristen M.; Oh, JiHyun; Kenney, Elizabeth; Smith-Bonahue, Tina
2016-01-01
Young children's outdoor play serves important and diverse purposes, including physical exercise and opportunities for growth in all developmental areas. Unfortunately, the amount of time that children spend engaged in unstructured, child-directed outdoor play has diminished significantly in the past generation. In this article, the authors…
Beneficial impact of exercise and obesity interventions on erectile function and its risk factors.
Hannan, Johanna L; Maio, M Tina; Komolova, Marina; Adams, Michael A
2009-03-01
Erectile dysfunction (ED) is a multifaceted disease involving cardiovascular, metabolic, and hormonal factors and affects over 100 million men worldwide. ED has been shown to be a harbinger of underlying cardiovascular diseases (CVD), as there are common risk factors (aging, hypertension, obesity) and mechanistic basis. To provide an update on clinical and experimental evidence regarding the impact of lifestyle modifications, such as exercise and diet, with respect to changes in erectile function. Published evidence regarding the impact of aging, hypertension, and obesity on ED and CVD, as well as new experimental data linking obesity and diminished erectile responses. We reviewed the literature regarding common risk factors of ED and CVD, particularly involving obesity, as well as performed new analysis on the findings of other experimental studies involving diet and exercise interventions. Physical inactivity negatively impacts on erectile function, and experimental and clinical exercise interventions have been shown to improve sexual responses and overall cardiovascular health. Mediterranean-style diets and a reduction in caloric intake have been found to improve erectile function in men with the aspects of the metabolic syndrome. In addition, both clinical and experimental studies have confirmed that combining the two interventions provides additional benefit to erectile function, likely via reduced metabolic disturbances (e.g., inflammatory markers, insulin resistance), decreased visceral adipose tissue, and improvement in vascular function (e.g., increased endothelial function). Lifestyle modifications provide significant benefits to vascular health and erectile function in a population that is increasingly aged and more obese.
NASA Technical Reports Server (NTRS)
Figueroa, Fernando
1999-01-01
It is hypothesized that bone loss experienced by astronauts in zero gravity conditions may be curtailed by appropriate exercise. According to Wolf's law, bone regenerates when muscles produce stresses by pulling on the bone during daily activity and/or exercise on Earth. To use this theory to prevent or decrease bone loss, one needs to quantify musculoskeletal loads and relate them to bone density changes. In the context of the space program, it is desirable to determine musculoskeletal loads during exercise so that one may make similar measurements on Earth and in space. In this manner, load measurements on Earth may be used as reference to generate similar loads during exercise in space. A research project to investigate the effects of high-resistive exercise to decrease bone density loss underzero-gravity conditions is being carried out in Life Sciences Research Laboratories at NASA JSC. The project consists of a bed-rest study whereby subjects remain in horizontal position for seventeen weeks. During the study, a subset of those subjects executes a regime of resistive exercises in the horizontal exercise machine (HEM). The HEM was designed so that subjects remain horizontal while exercising to minimize gravity loading even during exercise. Bone density of each subject is measured throughout the duration of their participation. The objective of the study is to determine if the resistive exercises are effective in diminishing or eliminating bone loss. My participation in this project relates to instrumentation, measurement, and processing of signals from displacement sensors (optical encoders) and load-cells. Measurement of displacements will be used to determine the motion of the body during exercise, and load measurements will be used (along with displacement data) to determine forces and torques exerted on each section of the body during exercise. Further, I have assisted in specifying new sensors to be added to the HEM and to a new prototype resistive exercise machine called the Interim Resistive Exercise Device (IRED). New load cells and encoders should be mounted in these devices to obtain more complete kineto-dynamic information. This report includes a description of the instrumentation that was built to perform measurements in the HEM and the IRED, along with the software that was developed to collect the measurements. It also includes examples of measurements taken in the HEM. Finally, a plan is laid out that describes how these measurements may be used to determine forces exerted by muscles for each exercise.
Smokeless tobacco, sport and the heart.
Chagué, Frédéric; Guenancia, Charles; Gudjoncik, Aurélie; Moreau, Daniel; Cottin, Yves; Zeller, Marianne
2015-01-01
Smokeless tobacco (snuff) is a finely ground or shredded tobacco that is sniffed through the nose or placed between the cheek and gum. Chewing tobacco is used by putting a wad of tobacco inside the cheek. Smokeless tobacco is widely used by young athletes to enhance performance because nicotine improves some aspects of physiology. However, smokeless tobacco has harmful health effects, including cardiovascular disorders, linked to nicotine physiological effects, mainly through catecholamine release. Nicotine decreases heart rate variability and the ventricular fibrillation threshold, and promotes the occurrence of various arrhythmias; it also impairs endothelial-dependent vasodilation and could therefore promote premature atherogenesis. At rest, heart rate, blood pressure, inotropism, cardiac output and myocardial oxygen consumption are increased by nicotine, leading to an imbalance between myocardial oxygen demand and supply. The same occurs at submaximal levels of exercise. These increases are accompanied by a rise in systemic resistances. At maximal exercise, heart rate, cardiac output and maximal oxygen uptake (V˙O2max) are unaffected by nicotine. Because endothelial dysfunction is promoted by nicotine, paradoxical coronary vasoconstriction may occur during exercise and recovery. Nicotine induces a decrease in muscular strength and impairs anaerobic performance. However, nicotine is used in sports as it diminishes anxiety, enhances concentration and agility, improves aerobic performance and favours weight control. Importantly, smokeless tobacco, similar to cigarette smoking, leads to nicotine dependence through dopaminergic pathways. Smokeless tobacco has harmful cardiovascular effects and is addictive: it fulfils all the criteria for inclusion in the World Anti-Doping Agency prohibited list as a doping product. Smokeless tobacco use in sporting activities must be discouraged. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Gorbea Chávez, Viridiana; Velázquez Sánchez, María del Pilar; Kunhardt Rasch, Jorge R
2004-12-01
The main factor for the appearance of urinary stress incontinence in almost all women is pregnancy and vaginal childbirth. The pelvic floor exercises have been described for the treatment of urinary stress incontinence. To determine with a randomized controlled trial if the pelvic floor exercises during pregnancy and late puerperium diminish the prevalence of urinary stress incontinence at 28 and 35 gestational week and at 6 weeks after childbirth. The study was made with nulliparous, pregnant women who realized pelvic floor exercises during pregnancy and after birth. 72 women were studied, 52.7% realized pelvic floor exercises and 47.2% did not. The urinary stress incontinence frequency at the 28 gestational week in the no exercises group was 17.2%, and at the 35 gestational week of 47% and at 6 weeks after childbirth was of 47%, while in the exercises group was 0, 0 and 15%, respectively. Moreover there were statistically significant differences between both groups regarding the presence of urinary stress incontinence, that is, the group that realized exercises presented less incontinence at the 28 and 35 gestational weeks and at 6 weeks after childbirth. The results of this study concluded that the pelvic floor exercises during pregnancy and after childbirth prevent the urinary stress incontinence at this time.
Fujii, Naoto; Aoki-Murakami, Erii; Tsuji, Bun; Kenny, Glen P; Nagashima, Kei; Kondo, Narihiko; Nishiyasu, Takeshi
2017-11-01
We evaluated cold sensation at rest and in response to exercise-induced changes in core and skin temperatures in cold-sensitive exercise trained females. Fifty-eight trained young females were screened by a questionnaire, selecting cold-sensitive (Cold-sensitive, n = 7) and non-cold-sensitive (Control, n = 7) individuals. Participants rested in a room at 29.5°C for ~100 min after which ambient temperature was reduced to 23.5°C where they remained resting for 60 min. Participants then performed 30-min of moderate intensity cycling (50% peak oxygen uptake) followed by a 60-min recovery. Core and mean skin temperatures and cold sensation over the whole-body and extremities (fingers and toes) were assessed throughout. Resting core temperature was lower in the Cold-sensitive relative to Control group (36.4 ± 0.3 vs. 36.7 ± 0.2°C). Core temperature increased to similar levels at end-exercise (~37.2°C) and gradually returned to near preexercise rest levels at the end of recovery (>36.6°C). Whole-body cold sensation was greater in the Cold-sensitive relative to Control group during resting at a room temperature of 23.5°C only without a difference in mean skin temperature between groups. In contrast, cold sensation of the extremities was greater in the Cold-sensitive group prior to, during and following exercise albeit this was not paralleled by differences in mean extremity skin temperature. We show that young trained females who are sensitive to cold exhibit augmented whole-body cold sensation during rest under temperate ambient conditions. However, this response is diminished during and following exercise. In contrast, cold sensation of extremities is augmented during resting that persists during and following exercise. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.
Code of Federal Regulations, 2010 CFR
2010-01-01
... affect a paying bank's liability to its customer under the U.C.C. or other law. (b) Paying bank's failure... provision, but not both. (c) Comparative negligence. If a person, including a bank, fails to exercise... person under § 229.38(a) shall be diminished in proportion to the amount of negligence or bad faith...
Hamstring injuries: prevention and treatment—an update
Brukner, Peter
2015-01-01
Despite increased knowledge of hamstring muscle injuries, the incidence has not diminished. We now know that not all hamstring injuries are the same and that certain types of injuries require prolonged rehabilitation and return to play. The slow stretch type of injury and injuries involving the central tendon both require longer times to return to play. A number of factors have been proposed as being indicators of time taken to return to play, but the evidence for these is conflicting. Recurrence rates remain high and it is now thought that strength deficits may be an important factor. Strengthening exercise should be performed with the hamstrings in a lengthened position. There is conflicting evidence regarding the efficacy of platelet-rich plasma injection in the treatment of hamstring injuries so at this stage we cannot advise their use. Various tests have been proposed as predictors of hamstring injury and the use of the Nordboard is an interesting addition to the testing process. Prevention of these injuries is the ultimate aim and there is increasing evidence that Nordic hamstring exercises are effective in reducing the incidence. PMID:26105015
Bone marrow fat accumulation accelerated by high fat diet is suppressed by exercise
Styner, Maya; Thompson, William R.; Galior, Kornelia; Uzer, Gunes; Wu, Xin; Kadari, Sanjay; Case, Natasha; Xie, Zhihui; Sen, Buer; Romaine, Andrew; Pagnotti, Gabriel M.; Rubin, Clinton T.; Styner, Martin A.; Horowitz, Mark C.; Rubin, Janet
2014-01-01
Marrow adipose tissue (MAT), associated with skeletal fragility and hematologic insufficiency, remains poorly understood and difficult to quantify. We tested the response of MAT to high fat diet (HFD) and exercise using a novel volumetric analysis, and compared it to measures of bone quantity. We hypothesized that HFD would increase MAT and diminish bone quantity, while exercise would slow MAT acquisition and promote bone formation. Eight week-old female C57BL/6 mice were fed a regular (RD) or HFD, and exercise groups were provided voluntary access to running wheels (RD-E, HFD-E). Femoral MAT was assessed by μCT (lipid binder osmium) using a semi-automated approach employing rigid co-alignment, regional bone masks and was normalized for total femoral volume (TV) of the bone compartment. MAT was 2.6-fold higher in HFD relative to RD mice. Exercise suppressed MAT in RD-E mice by more than half compared with RD. Running similarly inhibited MAT acquisition in HFD mice. Exercise significantly increased bone quantity in both diet groups. Thus, HFD caused significant accumulation of MAT; importantly running exercise limited MAT acquisition while promoting bone formation during both diets. That MAT is exquisitely responsive to diet and exercise, and its regulation by exercise appears to be inversely proportional to effects on exercise induced bone formation, is relevant for an aging and sedentary population. PMID:24709686
Effects of microgravity on rat muscle
NASA Technical Reports Server (NTRS)
Riley, D. A.
1990-01-01
It is well known that humans exposed to long term spaceflight experience undesirable progressive muscle weakness and increased fatigability. This problem has prompted the implementation of inflight exercise programs because most investigators believe that the major cause of diminished muscle performance is a combination of disuse and decreased workload. Inflight exercise has improved muscle health, but deficits have persisted, indicating that either the regimens utilized were suboptimal or there existed additional debilitating factors which were not remedied by exercise. Clarification of this question requires an improved understanding of the cellular and molecular basis of spaceflight-induced muscle deterioration. To this end, multiple investigations have been performed on the muscles from rats orbited 5 to 22 days in Cosmos biosatellites and Spacelab-3 (2,4,5,8,10 to 14,16,18,19,21 to 23,25,27,28). The eight Cosmos 1887 investigations examined the structural and biochemical changes in skeletal and cardiac muscles of rats exposed to microgravity for 12.5 days and returned to terrestrial gravity 2.3 days before tissues were collected. Even though interpretation of these results was complicated by the combination of inflight and postflight induced alterations, the consensus is that there is marked heterogeneity in both degree and type of responses from the whole muscle level down to the molecular level. Collectively, the muscle investigations of Cosmos 1887 clearly illustrate the wide diversity of muscle tissue responses to spaceflight. Judging from the summary report of this mission, heterogeneity of responses is not unique to muscle tissue. Elucidating the mechanism underlying this heterogeneity holds the key to explaining adaptation of the organism to prolonged spaceflight.
Giardino, Nicholas D; Curtis, Jeffrey L; Andrei, Adin-Cristian; Fan, Vincent S; Benditt, Joshua O; Lyubkin, Mark; Naunheim, Keith; Criner, Gerard; Make, Barry; Wise, Robert A; Murray, Susan K; Fishman, Alfred P; Sciurba, Frank C; Liberzon, Israel; Martinez, Fernando J
2010-03-09
Anxiety in patients with chronic obstructive pulmonary disease (COPD) is associated with self-reported disability. The purpose of this study is to determine whether there is an association between anxiety and functional measures, quality of life and dyspnea. Data from 1828 patients with moderate to severe emphysema enrolled in the National Emphysema Treatment Trial (NETT), collected prior to rehabilitation and randomization, were used in linear regression models to test the association between anxiety symptoms, measured by the Spielberger State Trait Anxiety Inventory (STAI) and: (a) six-minute walk distance test (6 MWD), (b) cycle ergometry peak workload, (c) St. Georges Respiratory Questionnaire (SRGQ), and (d) UCSD Shortness of Breath Questionnaire (SOBQ), after controlling for potential confounders including age, gender, FEV1 (% predicted), DLCO (% predicted), and the Beck Depression Inventory (BDI). Anxiety was significantly associated with worse functional capacity [6 MWD (B = -0.944, p < .001), ergometry peak workload (B = -.087, p = .04)], quality of life (B = .172, p < .001) and shortness of breath (B = .180, p < .001). Regression coefficients show that a 10 point increase in anxiety score is associated with a mean decrease in 6 MWD of 9 meters, a 1 Watt decrease in peak exercise workload, and an increase of almost 2 points on both the SGRQ and SOBQ. In clinically stable patients with moderate to severe emphysema, anxiety is associated with worse exercise performance, quality of life and shortness of breath, after accounting for the influence of demographic and physiologic factors known to affect these outcomes. ClinicalTrials.gov NCT00000606.
Hackett, Daniel A.; Baker, Michael K.
2016-01-01
The purpose of this study was to examine the effect of regular exercise training on insulin sensitivity in adults with type 2 diabetes mellitus (T2DM) using the pooled data available from randomised controlled trials. In addition, we sought to determine whether short-term periods of physical inactivity diminish the exercise-induced improvement in insulin sensitivity. Eligible trials included exercise interventions that involved ≥3 exercise sessions, and reported a dynamic measurement of insulin sensitivity. There was a significant pooled effect size (ES) for the effect of exercise on insulin sensitivity (ES, –0.588; 95% confidence interval [CI], –0.816 to –0.359; P<0.001). Of the 14 studies included for meta-analyses, nine studies reported the time of data collection from the last exercise bout. There was a significant improvement in insulin sensitivity in favour of exercise versus control between 48 and 72 hours after exercise (ES, –0.702; 95% CI, –1.392 to –0.012; P=0.046); and this persisted when insulin sensitivity was measured more than 72 hours after the last exercise session (ES, –0.890; 95% CI, –1.675 to –0.105; P=0.026). Regular exercise has a significant benefit on insulin sensitivity in adults with T2DM and this may persist beyond 72 hours after the last exercise session. PMID:27535644
Rural Young People and Society: A Crisis of Attitudes
ERIC Educational Resources Information Center
Gur'ianova, M. P.
2013-01-01
Research on rural youth in Russia shows that keeping qualified and ambitious young people in the rural economy will require creating conditions for young people to exercise initiative in the rural economy and diminishing the gap in quality of life between rural and urban environments. Only in this way can the pessimism of rural youth be overcome.
The Role of Sport/Fitness and Eating Disorders: Cosmetic Fitness from Starvation to Steroids.
ERIC Educational Resources Information Center
Moriarty, Dick; And Others
The incidence of eating disorders is much higher among children and young adults involved in sport and fitness activities. When weight loss is followed by excessive exercise, certain biological and social reinforcers become evident. This is also followed by a diminished appetite, increased narcissistic investment in the body, and an elevated…
USDA-ARS?s Scientific Manuscript database
Older individuals have a reduced capacity to induce muscle hypertrophy with resistance exercise (RE), which may contribute to the age-induced loss of muscle mass and function, sarcopenia. We tested the novel hypothesis that dysregulation of microRNAs (miRNAs) may contribute to reduced muscle plastic...
Staib, Jessica L.; Tümer, Nihal; Powers, Scott K.
2010-01-01
Myocardial heat shock protein 72 (HSP72) expression, mediated by its transcription factor heat shock factor 1 (HSF1), increases following exercise. However, the up-stream stimuli governing exercise-induced HSF1 activation and subsequent HSP72 gene expression in the whole animal remain unclear. Exercise-induced increases in body temperature may promote myocardial radical production leading to protein oxidation. Conceivably, myocardial protein oxidation during exercise may serve as an important signal promoting nuclear HSF1 migration and activation of HSP72 expression. Therefore, these experiments tested the hypothesis that preventing exercise-induced increases in body temperature attenuates cardiac protein oxidation, diminishes HSF1 activation and decreases HSP72 expression in vivo. To test this hypothesis, in vivo exercise-induced body temperature was manipulated by exercising male rats in either cold (4°C) or warm (22°C) ambient conditions. Warm exercise increased both body temperature (+ 3°C) and myocardial protein oxidation whereas these changes were attenuated by cold exercise. Interestingly, exercise in both conditions did not significantly increase myocardial nuclear localized phosphorylated HSF1. Nonetheless, warm exercise elevated left-ventricular HSP72 mRNA by 9-fold and increased myocardial HSP72 protein levels by 3-fold compared to cold-exercised animals. Collectively, these data indicate that elevated body temperature and myocardial protein oxidation promoted exercise-induced cardiac HSP72 mRNA expression and protein accumulation following in vivo exercise. However, these results suggest that exercise-induced myocardial HSP72 protein accumulation is not a result of nuclear-localized, phosphorylated HSF1 indicating that other transcriptional or posttranscriptional regulatory mechanisms are involved in exercise-induced HSP72 expression. PMID:18931043
Shafer, K M; Janssen, L; Carrick-Ranson, G; Rahmani, S; Palmer, D; Fujimoto, N; Livingston, S; Matulevicius, S A; Forbess, L W; Brickner, B; Levine, B D
2015-01-01
We aimed to assess the haemodynamic effects of exercise training in transposition of the great arteries (TGA) patients with systemic right ventricles (SRVs). TGA patients have limited exercise tolerance and early mortality due to systemic (right) ventricular failure. Whether exercise training enhances or injures the SRV is unclear. Fourteen asymptomatic patients (34 ± 10 years) with TGA and SRV were enrolled in a 12 week exercise training programme (moderate and high-intensity workouts). Controls were matched on age, gender, BMI and physical activity. Exercise testing pre- and post- training included: (a) submaximal and peak; (b) prolonged (60 min) submaximal endurance and (c) high-intensity intervals. Oxygen uptake (; Douglas bag technique), cardiac output (, foreign-gas rebreathing), ventricular function (echocardiography and cardiac MRI) and serum biomarkers were assessed. TGA patients had lower peak , , and stroke volume (SV), a blunted / slope, and diminished SV response to exercise (SV increase from rest: TGA = 15.2%, controls = 68.9%, P < 0.001) compared with controls. After training, TGA patients increased peak by 6 ± 8.5%, similar to controls (interaction P = 0.24). The magnitude of SV reserve on initial testing correlated with training response (r = 0.58, P = 0.047), though overall, no change in peak was observed. High-sensitivity troponin T (hs-TnT) and N-terminal prohormone of brain naturetic peptide (NT pro-BNP) were low and did not change with acute exercise or after training. Our data show that TGA patients with SRVs in this study safely participated in exercise training and improved peak . Neither prolonged submaximal exercise, nor high-intensity intervals, nor short-term exercise training seem to injure the systemic right ventricle. Key Points Patients with transposition of the great arteries (TGA) and systemic right ventricles have premature congestive heart failure; there is also a growing concern that athletes who perform extraordinary endurance exercise may injure the right ventricle. Therefore we felt it essential to determine whether exercise training might injure a systemic right ventricle which is loaded with every heartbeat. Previous studies have shown that short term exercise training is feasible in TGA patients, but its effect on ventricular function is unclear. We demonstrate that systemic right ventricular function is preserved (and may be improved) in TGA patients with exercise training programmes that are typical of recreational and sports participation, with no evidence of injury on biomarker assessment. Stroke volume reserve during exercise correlates with exercise training response in our TGA patients, identifying this as a marker of a systemic right ventricle (SRV) that may most tolerate (and possibly even be improved by) exercise training. PMID:25809342
A Scientific Rationale to Improve Resistance Training Prescription in Exercise Oncology.
Fairman, Ciaran M; Zourdos, Michael C; Helms, Eric R; Focht, Brian C
2017-08-01
To date, the prevailing evidence in the field of exercise oncology supports the safety and efficacy of resistance training to attenuate many oncology treatment-related adverse effects, such as risk for cardiovascular disease, increased fatigue, and diminished physical functioning and quality of life. Moreover, findings in the extant literature supporting the benefits of exercise for survivors of and patients with cancer have resulted in the release of exercise guidelines from several international agencies. However, despite research progression and international recognition, current exercise oncology-based exercise prescriptions remain relatively basic and underdeveloped, particularly in regards to resistance training. Recent publications have called for a more precise manipulation of training variables such as volume, intensity, and frequency (i.e., periodization), given the large heterogeneity of a cancer population, to truly optimize clinically relevant patient-reported outcomes. Indeed, increased attention to integrating fundamental principles of exercise physiology into the exercise prescription process could optimize the safety and efficacy of resistance training during cancer care. The purpose of this article is to give an overview of the current state of resistance training prescription and discuss novel methods that can contribute to improving approaches to exercise prescription. We hope this article may facilitate further evaluation of best practice regarding resistance training prescription, monitoring, and modification to ultimately optimize the efficacy of integrating resistance training as a supportive care intervention for survivors or and patients with cancer.
Iwamoto, Gary A.; Vongpatanasin, Wanpen; Mitchell, Jere H.; Smith, Scott A.
2015-01-01
Cardiovascular responses to exercise are exaggerated in hypertension. We previously demonstrated that this heightened cardiovascular response to exercise is mediated by an abnormal skeletal muscle exercise pressor reflex (EPR) with important contributions from its mechanically and chemically sensitive components. Exercise training attenuates exercise pressor reflex function in healthy subjects as well as in heart failure rats. However, whether exercise training has similar physiological benefits in hypertension remains to be elucidated. Thus we tested the hypothesis that the EPR overactivity manifest in hypertension is mitigated by exercise training. Changes in mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) in response to muscle contraction, passive muscle stretch, and hindlimb intra-arterial capsaicin administration were examined in untrained normotensive Wistar-Kyoto rats (WKYUT; n = 6), exercise-trained WKY (WKYET; n = 7), untrained spontaneously hypertensive rats (SHRUT; n = 8), and exercise-trained SHR (SHRET; n = 7). Baseline MAP after decerebration was significantly decreased by 3 mo of wheel running in SHRET (104 ± 9 mmHg) compared with SHRUT (125 ± 10 mmHg). As previously reported, the pressor and renal sympathetic responses to muscle contraction, stretch, and capsaicin administration were significantly higher in SHRUT than WKYUT. Exercise training significantly attenuated the enhanced contraction-induced elevations in MAP (SHRUT: 53 ± 11 mmHg; SHRET: 19 ± 3 mmHg) and RSNA (SHRUT: 145 ± 32%; SHRET: 57 ± 11%). Training produced similar attenuating effects in SHR during passive stretch and capsaicin administration. These data demonstrate that the abnormally exaggerated EPR function that develops in hypertensive rats is significantly diminished by exercise training. PMID:26163445
Effect of n-3 fatty acids on free tryptophan and exercise fatigue.
Huffman, Derek M; Altena, Thomas S; Mawhinney, Thomas P; Thomas, Tom R
2004-08-01
Free tryptophan (Trp), which is augmented by liberated free fatty acids (FFA) from adipose tissue, can induce mental fatigue via serotonin during exercise. Since an attenuation in FFA has been observed with omega-3 fatty acid (n-3fa) use, our purpose was to examine the effect of n-3fa supplementation on free Trp availability and exercise fatigue. Ten recreationally trained men ( n=5) and women ( n=5), with maximal oxygen consumption (VO(2max))of 51.6 (3.0) and 44.3 (1.4) ml kg(-1) min(-1), respectively, were studied on two occasions following an overnight fast, before and after n-3fa supplementation (4 g day(-1) for 4 weeks). The exercise trials consisted of a 75-min treadmill run at 60% VO(2max) followed immediately by a high-intensity incremental bout to fatigue. Measurements included exercise monitors, plasma volume (PV), triglycerides (TG), FFA, glycerol, lactate, and glucose. Free Trp and branched-chain amino acids (BCAA) were measured and correlated with time to fatigue; all blood variables were corrected for PV. Free Trp, lactate, glucose, FFA, and glycerol were not significantly different between trials, but TG ( P<0.001) and the free Trp/BCAA ratio were significantly lower after n-3fa use [1.76 (0.18)x10(-2) microg ml(-1)] versus before supplementation [2.17 (0.22), P=0.033]. There was a non-significant increase in time to fatigue after supplementation [10.2 (0.3) min] versus before n-3fa use [9.7 (0.2), P=0.068], and a tendency for higher BCAA levels after supplementation, P=0.068. However, neither free Trp nor the free Trp/BCAA ratio significantly predicted time to fatigue. In conclusion, n-3fa supplementation did not diminish free Trp concentrations or significantly improve endurance performance during a maximal bout of exercise.
Djordjevic, B; Baralic, I; Kotur-Stevuljevic, J; Stefanovic, A; Ivanisevic, J; Radivojevic, N; Andjelkovic, M; Dikic, N
2012-08-01
The purpose of the current study was to examine the effect of Astaxanthin (Asx) supplementation on muscle enzymes as indirect markers of muscle damage, oxidative stress markers and antioxidant response in elite young soccer players. Thirty-two male elite soccer players were randomly assigned in a double-blind fashion to Asx and placebo (P) group. After the 90 days of supplementation, the athletes performed a 2 hour acute exercise bout. Blood samples were obtained before and after 90 days of supplementation and after the exercise at the end of observational period for analysis of thiobarbituric acid-reacting substances (TBARS), advanced oxidation protein products (AOPP), superoxide anion (O2•¯), total antioxidative status (TAS), sulphydril groups (SH), superoxide-dismutase (SOD), serum creatine kinase (CK) and aspartate aminotransferase (AST). TBARS and AOPP levels did not change throughout the study. Regular training significantly increased O2•¯ levels (main training effect, P<0.01). O2•¯ concentrations increased after the soccer exercise (main exercise effect, P<0.01), but these changes reached statistical significance only in the P group (exercise x supplementation effect, P<0.05). TAS levels decreased significantly post- exercise only in P group (P<0.01). Both Asx and P groups experienced increase in total SH groups content (by 21% and 9%, respectively) and supplementation effect was marginally significant (P=0.08). Basal SOD activity significantly decreased both in P and in Asx group by the end of the study (main training effect, P<0.01). All participants showed a significant decrease in basal CK and AST activities after 90 days (main training effect, P<0.01 and P<0.001, respectively). CK and AST activities in serum significantly increased as result of soccer exercise (main exercise effect, P<0.001 and P<0.01, respectively). Postexercise CK and AST levels were significantly lower in Asx group compared to P group (P<0.05) The results of the present study suggest that soccer training and soccer exercise are associated with excessive production of free radicals and oxidative stress, which might diminish antioxidant system efficiency. Supplementation with Asx could prevent exercise induced free radical production and depletion of non-enzymatic antioxidant defense in young soccer players.
Meade, Robert D; Fujii, Naoto; Alexander, Lacy M; Paull, Gabrielle; Louie, Jeffrey C; Flouris, Andreas D; Kenny, Glen P
2015-01-01
Abstract Nitric oxide (NO)-dependent cutaneous vasodilatation is reportedly diminished during exercise performed at a high (700 W) relative to moderate (400 W) rate of metabolic heat production. The present study evaluated whether this impairment results from increased oxidative stress associated with an accumuluation of reactive oxygen species (ROS) during high intensity exercise. On two separate days, 11 young (mean ± SD, 24 ± 4 years) males cycled in the heat (35°C) at a moderate (500 W) or high (700 W) rate of metabolic heat production. Each session included two 30 min exercise bouts followed by 20 and 40 min of recovery, respectively. Cutaneous vascular conductance (CVC) was monitored at four forearm skin sites continuously perfused via intradermal microdialysis with: (1) lactated Ringer solution (Control); (2) 10 mm ascorbate (Ascorbate); (3) 10 mm l-NAME; or (4) 10 mm ascorbate + 10 mm l-NAME (Ascorbate + l-NAME). At the end of each 500 W exercise bout, CVC was attenuated with l-NAME (∼35% CVCmax) and Ascorbate + l-NAME (∼43% CVCmax) compared to Control (∼60% CVCmax; all P < 0.04); however, Ascorbate did not modulate CVC during exercise (∼60% CVCmax; both P > 0.87). Conversely, CVC was elevated with Ascorbate (∼72% CVCmax; both P < 0.03) but remained similar to Control (∼59% CVCmax) with l-NAME (∼50% CVCmax) and Ascorbate + l-NAME (∼47% CVCmax; all P > 0.05) at the end of both 700 W exercise bouts. We conclude that oxidative stress associated with an accumulation of ascorbate-sensitive ROS impairs NO-dependent cutaneous vasodilatation during intense exercise. Key points Recent work demonstrates that nitric oxide (NO) contributes to cutaneous vasodilatation during moderate (400 W of metabolic heat production) but not high (700 W of metabolic heat production) intensity exercise bouts performed in the heat (35°C). The present study evaluated whether the impairment in NO-dependent cutaneous vasodilatation was the result of a greater accumulation of reactive oxygen species during high (700 W of metabolic heat production) relative to moderate (500 W of metabolic heat production) intensity exercise. It was shown that local infusion of ascorbate (an anti-oxidant) improves NO-dependent forearm cutaneous vasodilatation during high intensity exercise in the heat. These findings provide novel insight into the physiological mechanisms governing cutaneous blood flow during exercise-induced heat stress and provide direction for future research exploring whether oxidative stress underlies the impairments in heat dissipation that may occur in older adults, as well as in individuals with pathophysiological conditions such as type 2 diabetes. PMID:26110415
Moayeri, A; Mokhtari, T; Hedayatpour, A; Abbaszadeh, H-A; Mohammadpour, S; Ramezanikhah, H; Shokri, S
2018-04-01
Oxygen consumption increases many times during exercise, which can increase reactive oxygen species. It negatively affects fertility in male athletes. Melatonin is exerting a regulatory role at different levels of the hypothalamic-pituitary-gonadal axis. However, there is no evidence that the protective effects of melatonin persist after long duration exercise on the spermatogenesis. Therefore, this study was conducted to examine the impacts of melatonin on the testis following the administration of swimming exercise. Rats were separated into five different groups, including Control, sham M: received the solvent of melatonin, M: received melatonin, S: the exercise protocol, MS: received melatonin and the exercise protocol. After 8 weeks, animals were scarified and antioxidant enzymes levels of testes, spermatogenic cells apoptosis and sperm quality were measured. Swimming decreased all parameters of spermatozoa. Nevertheless, melatonin could significantly improve the progressive motility of spermatozoa in MS rats. Swimming caused an increased apoptosis of S group and decreased all antioxidant enzymes. Melatonin could drastically reduce apoptosis and increased these enzymes. Therefore, melatonin seems to induce the production of antioxidant enzymes of testicular tissues and diminish the extent of apoptotic changes caused by forced exercise on the testis, which can, in turn, ameliorate the sperm parameters. © 2017 Blackwell Verlag GmbH.
Desveaux, Laura; Harrison, Samantha; Lee, Annemarie; Mathur, Sunita; Goldstein, Roger; Brooks, Dina
Despite well-established improvements following rehabilitation, functional gains often diminish following discharge. To explore the attitudes of older adults with HF and COPD, who have completed rehabilitation, toward community-based exercise maintenance. Semi-structured interviews were conducted with 11 individuals with HF or COPD. Deductive thematic analysis uncovered three themes: 1) transitioning to community exercise is challenging, highlighting participants' struggle with unstructured maintenance and a lack of appropriate programs; 2) a structured, group-based program tailored to functional ability facilitates adherence, describing participants views on the importance of routine, and accountability; and 3) "We are all there for the same purpose" - participant support for integrated exercise, including the benefit of multiple perspectives and sustainability. A motivating program leader and access to appropriate facilities are key features to support adherence to prescribed activity. Tailored programs can be delivered consecutively to older adults with HF and COPD. Copyright © 2017 Elsevier Inc. All rights reserved.
Prado, Eduardo Seixas; de Rezende Neto, José Melquiades; de Almeida, Rosemeire Dantas; Dória de Melo, Marcelia Garcez; Cameron, Luiz-Claudio
2011-06-28
Hyperammonaemia is related to both central and peripheral fatigue during exercise. Hyperammonaemia in response to exercise can be reduced through supplementation with either amino acids or combined keto analogues and amino acids (KAAA). In the present study, we determined the effect of short-term KAAA supplementation on ammonia production in subjects eating a low-carbohydrate diet who exercise. A total of thirteen male cyclists eating a ketogenic diet for 3 d were divided into two groups receiving either KAAA (KEx) or lactose (control group; LEx) supplements. Athletes cycled indoors for 2 h, and blood samples were obtained at rest, during exercise and over the course of 1 h during the recovery period. Exercise-induced ammonaemia increased to a maximum of 35 % in the control group, but no significant increase was observed in the supplemented group. Both groups had a significant increase (approximately 35 %) in uraemia in response to exercise. The resting urate levels of the two groups were equivalent and remained statistically unchanged in the KEx group after 90 min of exercise; an earlier increase was observed in the LEx group. Glucose levels did not change, either during the trial time or between the groups. An increase in lactate levels was observed during the first 30 min of exercise in both groups, but there was no difference between the groups. The present results suggest that the acute use of KAAA diminishes exercise-induced hyperammonaemia.
Baschung Pfister, Pierrette; de Bruin, Eling D; Tobler-Ammann, Bernadette C; Maurer, Britta; Knols, Ruud H
2015-10-01
Physical exercise seems to be a safe and effective intervention in patients with inflammatory myopathy (IM). However, the optimal training intervention is not clear. To achieve an optimum training effect, physical exercise training principles must be considered and to replicate research findings, FITT components (frequency, intensity, time, and type) of exercise training should be reported. This review aims to evaluate exercise interventions in studies with IM patients in relation to (1) the application of principles of exercise training, (2) the reporting of FITT components, (3) the adherence of participants to the intervention, and (4) to assess the methodological quality of the included studies. The literature was searched for exercise studies in IM patients. Data were extracted to evaluate the application of the training principles, the reporting of and the adherence to the exercise prescription. The Downs and Black checklist was used to assess methodological quality of the included studies. From the 14 included studies, four focused on resistance, two on endurance, and eight on combined training. In terms of principles of exercise training, 93 % reported specificity, 50 % progression and overload, and 79 % initial values. Reversibility and diminishing returns were never reported. Six articles reported all FITT components in the prescription of the training though no study described adherence to all of these components. Incomplete application of the exercise training principles and insufficient reporting of the exercise intervention prescribed and completed hamper the reproducibility of the intervention and the ability to determine the optimal dose of exercise.
Popov, D V; Khusnutdinova, D R; Shenkman, B S; Vinogradova, O L; Kozlovskaya, I B
2004-07-01
The efficacy of countermeasure exercise for diminishing disturbances induced by microgravity in motor system and its visceral supply during different stages of long-duration flight was evaluated. The results of both bicycle and locomotor testing indicate that physical fitness of cosmonaut does not become worse in the course of the long-duration flight. On the contrary, the lowest fitness was recorded at the first stage of mission, just after one month of flight. The "dead period" at the beginning of space flight seems to be a manifestation of the acute decrease in physical condition on transition from 1 G to microgravity, when none of the regular countermeasure regimes is sufficiently effective and acute increase of volume and intensity of training is impossible under the conditions of space flight.
Ichthyophonus-induced cardiac damage: a mechanism for reduced swimming stamina in salmonids.
Kocan, R; Lapatra, S; Gregg, J; Winton, J; Hershberger, P
2006-09-01
Swimming stamina, measured as time-to-fatigue, was reduced by approximately two-thirds in rainbow trout experimentally infected with Ichthyophonus. Intensity of Ichthyophonus infection was most severe in cardiac muscle but multiple organs were infected to a lesser extent. The mean heart weight of infected fish was 40% greater than that of uninfected fish, the result of parasite biomass, infiltration of immune cells and fibrotic (granuloma) tissue surrounding the parasite. Diminished swimming stamina is hypothesized to be due to cardiac failure resulting from the combination of parasite-damaged heart muscle and low myocardial oxygen supply during sustained aerobic exercise. Loss of stamina in Ichthyophonus-infected salmonids could explain the poor performance previously reported for wild Chinook and sockeye salmon stocks during their spawning migration.
[Between the stigma and the law: legal abortion in Mexico City].
Lamas, Marta
2014-01-01
The present contribution is part of a research developed with qualitative social research methods. It offers part of the results attained in a study performed at a clinic belonging to Mexico City´s Government, and explores the effects on staff of the implementation of Legal Pregnancy Termination (ILE, for its initials in Spanish). The results highlights that, besides diminishing health risks in the women who abort, the use of misoprostol prompted assertive attitudes in many women, that reduced the negative effects produced by the stigma of abortion. It also acknowledges the persistence of stigma in the opinions of the health personnel. The empowering of the self-image of women who become subject to this procedure is due to the full exercise of their legal right.
Ichthyophonus-induced cardiac damage: a mechanism for reduced swimming stamina in salmonids
Kocan, R.; LaPatra, S.; Gregg, J.; Winton, J.; Hershberger, P.
2006-01-01
Swimming stamina, measured as time-to-fatigue, was reduced by approximately two-thirds in rainbow trout experimentally infected with Ichthyophonus. Intensity of Ichthyophonus infection was most severe in cardiac muscle but multiple organs were infected to a lesser extent. The mean heart weight of infected fish was 40% greater than that of uninfected fish, the result of parasite biomass, infiltration of immune cells and fibrotic (granuloma) tissue surrounding the parasite. Diminished swimming stamina is hypothesized to be due to cardiac failure resulting from the combination of parasite-damaged heart muscle and low myocardial oxygen supply during sustained aerobic exercise. Loss of stamina in Ichthyophonus-infected salmonids could explain the poor performance previously reported for wild Chinook and sockeye salmon stocks during their spawning migration. ?? 2006 Blackwell Publishing Ltd.
Implications of land rights reform for Indigenous health.
Watson, Nicole L
2007-05-21
In August 2006, the Aboriginal Land Rights (Northern Territory) Amendment Bill 2006 (Cwlth) was passed into law, introducing, among other things, a system of 99-year leases over Indigenous townships. The leasing scheme will diminish the control that traditional owners previously exercised over their lands. This is at odds with research indicating that control over land is a positive influence on Indigenous health.
Zhang, Hui-Jie; He, Jiang; Pan, Ling-Ling; Ma, Zhi-Min; Han, Cheng-Kun; Chen, Chung-Shiuan; Chen, Zheng; Han, Hai-Wei; Chen, Shi; Sun, Qian; Zhang, Jun-Feng; Li, Zhi-Bin; Yang, Shu-Yu; Li, Xue-Jun; Li, Xiao-Ying
2016-08-01
Nonalcoholic fatty liver disease (NAFLD) is a prevalent risk factor for chronic liver disease and cardiovascular disease. To compare the effects of moderate and vigorous exercise on intrahepatic triglyceride content and metabolic risk factors among patients with NAFLD. In this randomized clinical trial, participants with central obesity and NAFLD were recruited from community-based screening in Xiamen, China, from December 1, 2011, through December 25, 2013. Data analysis was performed from August 28, 2015, through December 15, 2015. Participants were randomly assigned to vigorous-moderate exercise (jogging 150 minutes per week at 65%-80% of maximum heart rate for 6 months and brisk walking 150 minutes per week at 45%-55% of maximum heart rate for another 6 months), moderate exercise (brisk walking 150 minutes per week for 12 months), or no exercise. Primary outcome, change in intrahepatic triglyceride content measured by proton magnetic resonance spectroscopy at 6 and 12 months; secondary outcomes, changes in body weight, waist circumference, body fat, and metabolic risk factors. A total of 220 individuals (mean [SD] age, 53.9 [7.1] years; 149 woman [67.7%]) were randomly assigned to control (n = 74), moderate exercise (n = 73), and vigorous-moderate exercise (n = 73) groups. Of them, 211 (95.9%) completed the 6-month follow-up visit; 208 (94.5%) completed the 12-month follow-up visit. Intrahepatic triglyceride content was reduced by 5.0% (95% CI, -7.2% to 2.8%; P < .001) in the vigorous-moderate exercise group and 4.2% (95% CI, -6.3% to -2.0%; P < .001) in the moderate exercise group compared with the control group at the 6-month assessment. It was reduced by 3.9% (95% CI, -6.0% to -1.7%; P < .001) in the vigorous-moderate exercise group and 3.5% (95% CI, -5.6% to -1.3%; P = .002) in the moderate exercise group compared with the control group at the 12-month assessment. Changes in intrahepatic triglyceride content were not significantly different between vigorous-moderate and moderate exercise at the 6- or 12-month assessment. Body weight, waist circumference, and blood pressure were significantly reduced in the vigorous-moderate exercise group compared with the moderate exercise and control groups at the 6-month assessment and in the vigorous-moderate and moderate exercise groups compared with the control group at the 12-month assessment. In addition, body fat was significantly reduced in the vigorous-moderate exercise group compared with the moderate exercise and control groups at the 12-month assessment. After adjusting for weight loss, the net changes in intrahepatic triglyceride content were diminished and became nonsignificant between the exercise and control groups (except for the moderate exercise group at the 6-month assessment). Vigorous and moderate exercise were equally effective in reducing intrahepatic triglyceride content; the effect appeared to be largely mediated by weight loss. clinicaltrials.gov Identifier: NCT01418027.
Streckmann, F; Kneis, S; Leifert, J A; Baumann, F T; Kleber, M; Ihorst, G; Herich, L; Grüssinger, V; Gollhofer, A; Bertz, H
2014-02-01
Lymphoma patients undergoing therapy must cope with the side-effects of the disease itself, therapy and associated immobility. Peripheral neuropathy (PNP), loss of balance control and weakness not only diminishes patients' quality of life (QOL), it can also affect planning and the dosage of therapy. Exercise may enable patients to reverse these declines, improving their performance level and QOL. We carried out a randomized, controlled trial, assigning 61 lymphoma patients either to a control group (CG; N=31) or to a 36-week intervention (IG; N=30), consisting of sensorimotor-, endurance- and strength training twice a week. Primary end point was QOL; secondary end points included movement coordination, endurance, strength and therapy-induced side-effects. Intergroup comparison revealed improved QOL- (ΔT1-T0; P=0.03) and PNP-related deep sensitivity in the IG: 87.5% were able to reduce the symptom, compared with 0% in the CG (P<0.001). Significant differences in the change of balance control could be found between the groups, with the IG improving while the CG steadily declined (monopedal static ΔT3-T0; P=0.03; dynamic ΔT3-T0; P=0.007; perturbed mono-ΔT3-T0; P=0.009 and bipedal ΔT3-T0; P=0.006), failed attempts (monopedal static ΔT3-T0; P=0.02, dynamic ΔT3-T0; P<0.001and perturbed ΔT3-T0; P=0.006) and improved time to regain balance (ΔT3-T0; P=0.04). Moreover, the change in the aerobic performance level (ΔT3-T0; P=0.05) and additional amount of exercise carried out per week [metabolic equivalent (MET); P=0.02] differed significantly across groups. Exercise, especially sensorimotor training, is a feasible and promising method to support cancer patients during therapy. It improves patients QOL, reduces restrictions from side-effects such as PNP and improves patients' balance control, physical performance level and mobility. DRKS00003894.
2012-01-01
Background Hematopoietic stem cell transplantation is an intensive therapy used to improve survivorship and cure various oncologic diseases. However, this therapy is associated with high mortality rates and numerous negative side-effects. The recovery of the immune system is a special concern and plays a key role in the success of this treatment. In healthy populations it is known that exercise plays an important role in immune system regulation, but little is known about the role of exercise in the hematological and immunological recovery of children undergoing hematopoietic stem cell transplant. The primary objective of this randomized-controlled trial (RCT) is to study the effect of an exercise program (in- and outpatient) on immune cell recovery in patients undergoing an autologous stem cell transplantation. The secondary objective is to determine if an exercise intervention diminishes the usual deterioration in quality of life, physical fitness, and the acquisition of a sedentary lifestyle. Methods This RCT has received approval from The Conjoint Health Research Ethics Board (CHREB) of the University of Calgary (Ethics ID # E-24476). Twenty-four participants treated for a malignancy with autologous stem cell transplant (5 to 18 years) in the Alberta Children’s Hospital will be randomly assigned to an exercise or control group. The exercise group will participate in a two-phase exercise intervention (in- and outpatient) from hospitalization until 10 weeks after discharge. The exercise program includes strength, flexibility and aerobic exercise. During the inpatient phase this program will be performed 5 times/week and will be supervised. The outpatient phase will combine a supervised session with two home-based exercise sessions with the use of the Wii device. The control group will follow the standard protocol without any specific exercise program. A range of outcomes, including quantitative and functional recovery of immune system, cytokine levels in serum, natural killer (NK) cells and their subset recovery and function, and gene expression of activating and inhibitory NK cell receptors, body composition, nutrition, quality of life, fatigue, health-related fitness assessment and physical activity levels will be examined, providing the most comprehensive assessment to date. Discussion We expect to find improvements in immunological recovery and quality of life, and decreased acquisition of sedentary behavior and fitness deconditioning. The comprehensive outcomes generated in this RCT will provide preliminary data to conduct a multisite study that will generate stronger outcomes. Trial registration Gov identification # NCT01666015 PMID:22963378
Effect of hypokinesia on cardiac contractile function and nervous regulation of the heart
NASA Technical Reports Server (NTRS)
Meyerson, F. Z.; Kapelko, V. I.; Gorina, M. S.; Shchegolkov, A. N.; Larinov, N. P.
1980-01-01
Longterm hypokinesia caused cardiac deadaptation in rabbits, which resulted in the diminishing of the left ventricular rate of contraction and relaxation, joined later by decreased vascular resistance. As a results, the ejection rate as well as stroke volume and cardiac output were normal. The decrease of the relaxation speed was more obvious at a high heart rate and results in shortening of the diastolic pause and diminishing of cardiac output. Hearts of the hypokinetic animals were characterized by normal maximal pressure developed by a unit of muccardial mass aorta clamping, decreased adrenoreactivity, and increased cholinoreactivity. This complex of changes is contrary to changes observed in adaptation to exercise, but is similar to changes observed in compensatory hypertrophy of the heart.
Increasing Optimism Protects Against Pain-Induced Impairment in Task-Shifting Performance.
Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L
2017-04-01
Persistent pain can lead to difficulties in executive task performance. Three core executive functions that are often postulated are inhibition, updating, and shifting. Optimism, the tendency to expect that good things happen in the future, has been shown to protect against pain-induced performance deterioration in executive function updating. This study tested whether this protective effect of a temporary optimistic state by means of a writing and visualization exercise extended to executive function shifting. A 2 (optimism: optimism vs no optimism) × 2 (pain: pain vs no pain) mixed factorial design was conducted. Participants (N = 61) completed a shifting task once with and once without concurrent painful heat stimulation after an optimism or neutral manipulation. Results showed that shifting performance was impaired when experimental heat pain was applied during task execution, and that optimism counteracted pain-induced deterioration in task-shifting performance. Experimentally-induced heat pain impairs shifting task performance and manipulated optimism or induced optimism counteracted this pain-induced performance deterioration. Identifying psychological factors that may diminish the negative effect of persistent pain on the ability to function in daily life is imperative. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.
2010-01-01
Background Anxiety in patients with chronic obstructive pulmonary disease (COPD) is associated with self-reported disability. The purpose of this study is to determine whether there is an association between anxiety and functional measures, quality of life and dyspnea. Methods Data from 1828 patients with moderate to severe emphysema enrolled in the National Emphysema Treatment Trial (NETT), collected prior to rehabilitation and randomization, were used in linear regression models to test the association between anxiety symptoms, measured by the Spielberger State Trait Anxiety Inventory (STAI) and: (a) six-minute walk distance test (6 MWD), (b) cycle ergometry peak workload, (c) St. Georges Respiratory Questionnaire (SRGQ), and (d) UCSD Shortness of Breath Questionnaire (SOBQ), after controlling for potential confounders including age, gender, FEV1 (% predicted), DLCO (% predicted), and the Beck Depression Inventory (BDI). Results Anxiety was significantly associated with worse functional capacity [6 MWD (B = -0.944, p < .001), ergometry peak workload (B = -.087, p = .04)], quality of life (B = .172, p < .001) and shortness of breath (B = .180, p < .001). Regression coefficients show that a 10 point increase in anxiety score is associated with a mean decrease in 6 MWD of 9 meters, a 1 Watt decrease in peak exercise workload, and an increase of almost 2 points on both the SGRQ and SOBQ. Conclusion In clinically stable patients with moderate to severe emphysema, anxiety is associated with worse exercise performance, quality of life and shortness of breath, after accounting for the influence of demographic and physiologic factors known to affect these outcomes. Trail Registration ClinicalTrials.gov NCT00000606 PMID:20214820
Noise-induced hearing loss caused by gunshot in South Korean military service.
Moon, In Seok
2007-04-01
Noise-induced hearing loss is a preventive disease and yet the effective treatment modality has not been established. Acute acoustic traumas caused by an exposure to gunshot noise are common in young South Korean males in military service. Considering the significant lack of awareness on this serious issue as well as the absence of proper protective gear, an in-depth analysis is desperately needed. All 3650 soldiers performed regular periodic gunfire exercise without any hearing protective measures. Seven patients with hearing impairment after periodic gunfire visited the aeromedical squadron; all were right-handed males. Six were tested with the K-2 rifle and one was tested with a K-5 revolver. History taking, physical examination, pure-tone audiometry, and impedance audiometry were conducted. In the next periodic gunfire exercise, all 3650 soldiers performed gunfire with unilateral hearing protection. The average outcome of postexposure air conduction thresholds was 6.5 dB in the right ear and 33.1 dB in the left ear. After medical treatment, hearing impairment was much improved; however, tinnitus was not diminished. In the next periodic gunfire exercise, the result of a supplement of unilateral earplug protection proved its effectiveness on acoustic trauma caused by gunfire noise. Asymmetry in hearing loss is related to the position of the head during gunfire. A unilateral hearing protection device was enough to protect hearing from gunfire noise. At the same time, it can effectively prevent a potential firearm accident that can be caused by trainees mishearing the instruction of a firearm instructor if both earplugs are worn. Thus, providing a unilateral earplug for protection against acoustic trauma must be taken into serious consideration.
Sista, Akhilesh K; Miller, Larry E; Kahn, Susan R; Kline, Jeffrey A
2017-02-01
Long-term right ventricular (RV) function, functional capacity, exercise capacity, and quality of life following pulmonary embolism (PE), and the impact of thrombolysis, are unclear. A systematic review of studies that evaluated these outcomes with ⩾ 3-month mean follow-up after PE diagnosis was performed. For each outcome, random effects meta-analyses were performed. Twenty-six studies (3671 patients) with 18-month median follow-up were included. The pooled prevalence of RV dysfunction was 18.1%. Patients treated with thrombolysis had a lower, but not statistically significant, risk of RV dysfunction versus those treated with anticoagulation (odds ratio: 0.51, 95% CI: 0.24 to 1.13, p=0.10). Pooled prevalence of at least mild functional impairment (NYHA II-IV) was 33.2%, and at least moderate functional impairment (NYHA III-IV) was 11.3%. Patients treated with thrombolysis had a lower, but not statistically significant, risk of at least moderate functional impairment versus those treated with anticoagulation (odds ratio: 0.48, 95% CI: 0.15 to 1.49, p=0.20). Pooled 6-minute walk distance was 415 m (95% CI: 372 to 458 m), SF-36 Physical Component Score was 44.8 (95% CI: 43 to 46), and Pulmonary Embolism Quality of Life (QoL) Questionnaire total score was 9.1. Main limitations included heterogeneity among studies for many outcomes, variation in the completeness of data reported, and inclusion of data from non-randomized, non-controlled, and retrospective studies. Persistent RV dysfunction, impaired functional status, diminished exercise capacity, and reduced QoL are common in PE survivors. The effect of thrombolysis on RV function and functional status remains unclear.
Brown, Richard A; Prince, Mark A; Minami, Haruka; Abrantes, Ana M
2016-10-01
Aerobic exercise is currently being studied as a relapse prevention strategy for individuals with alcohol use disorders. Negative affect and cravings predict relapse. The acute effects of moderate-intensity exercise have been shown to improve mood and reduce craving. The current study examined the acute effects of exercise on changes in mood, anxiety, and craving from pre- to post-exercise at each week of a 12-week moderate intensity exercise intervention with sedentary alcohol dependent adults. Twenty-six participants in the exercise condition of a larger randomized clinical trial (Brown et al., 2014) exercised in small groups at moderate intensity for 20 to 40 minutes per session. Participants rated mood, anxiety, and cravings in the present moment before and after each exercise session over the course of the 12-week intervention. Data analyses focused on effect size and interval estimation. Joinpoint analysis was used to model longitudinal trends. Increases in mood and decreases in anxiety and craving were apparent at every session. Effect size estimates revealed that average change from pre- to post-exercise was in the small to medium range with some individual sessions reaching the large range. Joinpoint analyses revealed that the pre-post exercise changes in mood increased, anxiety remained stable, and craving diminished across the 12 weeks. This study provides provisional support for a change in mood, anxiety and alcohol cravings for the role of exercise in the early recovery period for alcohol dependence. Acute single bouts of moderate-intensity exercise may help individuals with alcohol dependence manage mood, anxiety, and craving thereby reducing relapse risk, but further research is needed with a more rigorous study design.
Scharhag, Jürgen; Herrmann, Markus; Weissinger, Melanie; Herrmann, Wolfgang; Kindermann, Wilfried
2007-04-01
Elevated concentrations of B-type natriuretic peptide (BNP) and N-terminal pro- BNP (NT-proBNP) reflect elevated myocardial wall stress due to volume or pressure overload in cardiac disease. Recently, exercise-induced elevations of (NT-pro)BNP in coronary artery disease (CAD) patients have been reported to result from exercise-induced ischemia associated regional wall abnormalities. Therefore, the study aimed to examine NT-proBNP concentrations in patients with CAD after moderate and brisk walking (MW, BW). We hypothesized that BW induces higher increases than MW. In randomized order 14 patients with stable CAD (12 male symbol/2 female symbol; 63 +/- 9 years; LV ejection fraction: 59+/-9%) of a out-patient rehabilitation group performed MW with 4.5 +/- 0.6 km/h (mean heart rate: 80 +/- 11/min) or BWat their allowed upper exercise heart rate of 102+/-9/min with a speed of 6.2 +/- 0.6 km/h for 30 min on a tartan track on two separate days. Blood samples were taken before, immediately, 1 h, 3 h and 1 day after exercise to determine NT-proBNP and cardiac troponin T (cTnT). Echocardiographic LV function was determined before and 1 h after exercise. Median concentrations of NT-proBNP significantly increased from 222 to 295 ng/l (MW) and from 222 to 296 ng/l (BW) without a difference between both modalities. cTnT remained below the detection limit of 0.01 microg/l. LV functions remained unchanged. A cutoff level of 250 ng/l distinguished CAD patients with elevated exercise-induced increases in NT-proBNP and a diminished LV ejection fraction at rest. BW and MW induce similar increases in NT-proBNP in CAD patients without myocardial damage, which have to be considered when NT-proBNP is determined. Derived from the exercise- induced increase in NTproBNP, the myocardial strain in BW is not elevated in comparison to MW.
Yoshida, Sadamitsu; Adachi, Hitoshi; Murata, Makoto; Tomono, Junichi; Oshima, Shigeru; Kurabayashi, Masahiko
2017-09-01
Myocardial ischemia induces cardiac dysfunction, resulting in insufficient oxygen supply to peripheral tissues and mismatched energy production during exercise. To relieve the insufficient oxygen supply, heart rate (HR) response is augmented; however, beta-adrenergic receptor blockers (BB) restrict HR response. Although BB are essential drugs for angina pectoris, the effect of BB on exercise tolerance in patients with angina has not been studied. The aim of this study was to clarify the importance of HR augmentation to preserve exercise tolerance in patients with angina pectoris. Forty-two subjects who underwent cardiopulmonary exercise testing (CPX) to detect myocardial ischemia were enrolled. CPX was performed until exhaustion or onset of significant myocardial ischemia using a ramp protocol. Subjects were assigned to three groups (Group A: with ST depression during CPX with significant coronary stenosis and taking BB; Group B: with ST depression and not taking BB; Group C: without ST depression and not taking BB). HR response to exercise was evaluated during the following two periods: below and above ischemic threshold (IT). In Group C, it was evaluated during the first 2min and the last 2min of a ramp exercise. No significant differences were observed among the three groups with regard to patients' basic characteristics. Below IT, there were no differences in oxygen pulse/watt (O 2 pulse increasing rate), HR/watt (ΔHR/ΔWR), and ΔV˙O 2 /ΔWR. Above IT, O 2 pulse increasing rate was greater in Group A than in Group B. ΔHR/ΔWR was smaller in Group A than in Group B. ΔV˙O 2 /ΔWR became smaller in Group A than in Group B. There was no difference in anaerobic threshold, and peak V˙O 2 was smaller in Group A than in Group B. Restriction of HR response by a BB is shown to be one of the important factors in diminished exercise tolerance. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.
Cystatin C a marker for renal function after exercise.
Mingels, A; Jacobs, L; Kleijnen, V; Wodzig, W; Dieijen-Visser, M van
2009-09-01
Renal impairment is common during and after severe exercise. In clinical practice, renal function is evaluated using serum creatinine, urine parameters, and equations to estimate the Glomular Filtration Rate (GFR). However, creatinine levels may be biased by skeletal muscle damage and the GFR equations, requiring age, gender and body weight, are shown to be inadequate in normals. In the present study, we show that serum cystatin C and creatinine concentrations were elevated after marathon running in 26% and 46% of the 70 recreational male runners, respectively, possibly because of reduction in renal blood flow. The mean cystatin C increase was twice as low as compared to creatinine (21% and 41%, respectively), suggesting that cystatin C is indeed less biased by muscle damage. Future research has to reveal whether training diminishes the elevation in renal markers. Overall, cystatin C seems a more reliable method to establish renal function during and after extensive exercise. Georg Thieme Verlag KG Stuttgart.
Exercise recommendations for individuals with spinal cord injury.
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.
Riahi, Simin; Mohammadi, Mohammad Taghi; Sobhani, Vahid; Soleimany, Mansureh
2015-01-01
Objective(s): Lectin-like low density lipoprotein receptor (LOX-1) has pivot role in vascular complications, which is upregulated in numerous pathological conditions. Since exercise has beneficial effects in prevention of hyperlipidemic complications, present study examined protective effects of aerobic exercise through reduction of LOX-1 expression in heart during dyslipidemia. Materials and Methods: Four groups of rats were used (N=25): Normal, Normal and exercise, High fat and High fat and exercise. High fat diet (HFD) was made by adding 10% animal oil, 2% cholesterol and 0.5% colic acid to standard rodent chow. Exercise protocol consisted of swimming 1 hr/day, and 5 days/week for 8 weeks. Plasma lipids were evaluated at the end of experiment, 48 hr after final session of exercise. At the end, rats were sacrificed and heart was removed for determination of malondialdehyde (MDA) content, and LOX-1 expression. Results: HFD meaningfully changed lipid profile (>50%), but chronic exercise had no significant effects on lipid profile. LOX-1 expression was significantly increased in heart of rats fed with HFD, while swimming exercise considerably reduced gene expression of LOX-1. MDA content was significantly enhanced in rats fed with HFD (4.37±0.6 nmol/mg, P<0.01) compared to normal group (1.56±0.48 nmol/mg), whereas swimming exercise decreased MDA level of heart in rats fed with HFD (2.28±0.32, P<0.01). Conclusion: Findings indicated that swimming exercise is able to diminish heart expression of LOX-1 receptor concomitant reduction of oxidative stress. Since these parameters are involved in generation of dyslipidemic complications, swimming exercise is a good candidate to reduce these complications. PMID:26557970
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.
Halabchi, Farzin; Alizadeh, Zahra; Sahraian, Mohammad Ali; Abolhasani, Maryam
2017-09-16
Multiple sclerosis (MS) can result in significant mental and physical symptoms, specially muscle weakness, abnormal walking mechanics, balance problems, spasticity, fatigue, cognitive impairment and depression. Patients with MS frequently decrease physical activity due to the fear from worsening the symptoms and this can result in reconditioning. Physicians now believe that regular exercise training is a potential solution for limiting the reconditioning process and achieving an optimal level of patient activities, functions and many physical and mental symptoms without any concern about triggering the onset or exacerbation of disease symptoms or relapse. Appropriate exercise can cause noteworthy and important improvements in different areas of cardio respiratory fitness (Aerobic fitness), muscle strength, flexibility, balance, fatigue, cognition, quality of life and respiratory function in MS patients. Aerobic exercise training with low to moderate intensity can result in the improvement of aerobic fitness and reduction of fatigue in MS patients affected by mild or moderate disability. MS patients can positively adapt to resistance training which may result in improved fatigue and ambulation. Flexibility exercises such as stretching the muscles may diminish spasticity and prevent future painful contractions. Balance exercises have beneficial effects on fall rates and better balance. Some general guidelines exist for exercise recommendation in the MS population. The individualized exercise program should be designed to address a patient's chief complaint, improve strength, endurance, balance, coordination, fatigue and so on. An exercise staircase model has been proposed for exercise prescription and progression for a broad spectrum of MS patients. Exercise should be considered as a safe and effective means of rehabilitation in MS patients. Existing evidence shows that a supervised and individualized exercise program may improve fitness, functional capacity and quality of life as well as modifiable impairments in MS patients.
Lind, Erik; Welch, Amy S; Ekkekakis, Panteleimon
2009-01-01
Despite the well established physical and psychological benefits derived from leading a physically active life, rates of sedentary behaviour remain high. Dropout and non-compliance are major contributors to the problem of physical inactivity. Perceptions of exertion, affective responses (e.g. displeasure or discomfort), and physiological stress could make the exercise experience aversive, particularly for beginners. Shifting one's attentional focus towards environmental stimuli (dissociation) instead of one's body (association) has been theorized to enhance psychological responses and attenuate physiological stress. Research evidence on the effectiveness of attentional focus strategies, however, has been perplexing, covering the entire gamut of possible outcomes (association and dissociation having been shown to be both effective and ineffective). This article examines the effects of manipulations of attentional focus on exertional and affective responses, as well as on exercise economy and tolerance. The possible roles of the characteristics of the exercise stimulus (intensity, duration) and the exercise participants, methodological issues, and limitations of experimental designs are discussed. In particular, the critical role of exercise intensity is emphasized. Dissociative strategies may be more effective in reducing perceptions of exertion and enhancing affective responses at low to moderate exercise intensities, but their effectiveness may be diminished at higher and near-maximal levels, at which physiological cues dominate. Conversely, associative strategies could enable the exerciser to regulate intensity to avoid injury or overexertion. Thus, depending on intensity, both strategies have a place in the 'toolbox' of the public health or exercise practitioner as methods of enhancing the exercise experience and promoting long-term compliance.
Terwoord, Janée D; Hearon, Christopher M; Luckasen, Gary J; Richards, Jennifer C; Joyner, Michael J; Dinenno, Frank A
2018-05-03
The increase in interstitial potassium (K + ) during muscle contractions is thought to be a vasodilatory signal that contributes to exercise hyperemia. To determine the role of extracellular K + in exercise hyperemia, we perfused skeletal muscle with K + prior to contractions such that the effect of any endogenously-released K + would be minimized. We tested the hypothesis that local, intra-arterial infusion of potassium chloride (KCl) at rest would impair vasodilation in response to subsequent rhythmic handgrip exercise in humans. In 11 young adults, we determined forearm blood flow (FBF; Doppler ultrasound) and vascular conductance (FVC; FBF/mean arterial pressure) during 4 minutes of rhythmic handgrip exercise at 10% of maximal voluntary contraction during 1) control conditions (CTRL), 2) infusion of KCl prior to the initiation of exercise, and 3) infusion of sodium nitroprusside (SNP) as a control vasodilator. Infusion of KCl or SNP elevated resting FVC similarly prior to the onset of exercise (CTRL: 39 {plus minus} 6 vs. KCl: 81 {plus minus} 12 and SNP: 82 {plus minus} 13 ml/min/100 mmHg; both P < 0.05 vs. CTRL). Infusion of KCl at rest diminished the hyperemic (Δ FBF) and vasodilatory (Δ FVC) response to subsequent exercise by 22 {plus minus} 5% and 30 {plus minus} 5%, respectively (both P < 0.05 vs. CTRL), whereas SNP did not affect the change in FBF (P = 0.74 vs. CTRL) or FVC (P = 0.61 vs. CTRL) from rest to steady-state exercise. These findings implicate the K + ion as an essential vasodilator substance contributing to exercise hyperemia in humans.
Exercise attenuates the metabolic effects of dim light at night.
Fonken, Laura K; Meléndez-Fernández, O Hecmarie; Weil, Zachary M; Nelson, Randy J
2014-01-30
Most organisms display circadian rhythms that coordinate complex physiological and behavioral processes to optimize energy acquisition, storage, and expenditure. Disruptions to the circadian system with environmental manipulations such as nighttime light exposure alter metabolic energy homeostasis. Exercise is known to strengthen circadian rhythms and to prevent weight gain. Therefore, we hypothesized providing mice a running wheel for voluntary exercise would buffer against the effects of light at night (LAN) on weight gain. Mice were maintained in either dark (LD) or dim (dLAN) nights and provided either a running wheel or a locked wheel. Mice exposed to dim, rather than dark, nights increased weight gain. Access to a functional running wheel prevented body mass gain in mice exposed to dLAN. Voluntary exercise appeared to limit weight gain independently of rescuing changes to the circadian system caused by dLAN; increases in daytime food intake induced by dLAN were not diminished by increased voluntary exercise. Furthermore, although all of the LD mice displayed a 24h rhythm in wheel running, nearly half (4 out of 9) of the dLAN mice did not display a dominant 24h rhythm in wheel running. These results indicate that voluntary exercise can prevent weight gain induced by dLAN without rescuing circadian rhythm disruptions. © 2013.
Best, John R; Nagamatsu, Lindsay S; Liu-Ambrose, Teresa
2014-01-01
Previous studies have shown that exercise training benefits cognitive, neural, and physical health markers in older adults. It is likely that these positive effects will diminish if participants return to sedentary lifestyles following training cessation. Theory posits that that the neurocognitive processes underlying self-regulation, namely executive function (EF), are important to maintaining positive health behaviors. Therefore, we examined whether better EF performance in older women would predict greater adherence to routine physical activity (PA) over 1 year following a 12-month resistance exercise training randomized controlled trial. The study sample consisted of 125 community-dwelling women aged 65-75 years old. Our primary outcome measure was self-reported PA, as measured by the Physical Activity Scale for the Elderly (PASE), assessed on a monthly basis from month 13 to month 25. Executive function was assessed using the Stroop Test at baseline (month 0) and post-training (month 12). Latent growth curve analyses showed that, on average, PA decreased during the follow-up period but at a decelerating rate. Women who made greater improvements to EF during the training period showed better adherence to PA during the 1-year follow-up period (β = -0.36, p < 0.05); this association was unmitigated by the addition of covariates (β = -0.44, p < 0.05). As expected, EF did not predict changes in PA during the training period (p > 0.10). Overall, these findings suggest that improving EF plays an important role in whether older women maintain higher levels of PA following exercise training and that this association is only apparent after training when environmental support for PA is low.
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.
Yosef, Yoni; Schurr, Daniel; Constantini, Naama
2014-07-01
Statins are used for the prevention and treatment of cardiovascular disease. The treatment is quite safe but not free of side effects, particularly muscle pain. Fear of pain may prevent patients from carrying out exercise or diminish their motivation to return and engage in it, even though both the statins and the exercise have a proven benefit in both treatment and prevention, and a synergistic effect enhances this benefit. Prevalence of muscular pain ranges from 1-30%. Pain usually appears at the beginning of treatment, but can occur even after months and under any of the existing agents. The creatine phosphokinase (CPK) enzyme level may rise, but not necessarily. Increases to exceptional values (10 times the upper normal level) are relatively rare and rhabdomyolysis is extremely rare. The risk increases with age, co-morbidities and especially when taken concurrently with drugs that are metabolized in a similar pathway. Pain usually passes within a month after discontinuing treatment, but may persist for six months or more. Studies have examined the effect of statin therapy on the ability to perform physical activity, but results are inconsistent. The increased rise of CPK was observed under statin therapy, a tendency that increased with age. However, it was not accompanied by an increased incidence of muscle pain or rhabdomyolysis. Considering the above we recommend encouraging patients to exercise. However, patients should be instructed to report new or worsening muscular pains. Discontinuation, lowering dose or replacement should be considered when pain is suspected to be related with treatment.
Lopes-João, António; Costa, Inês; Mesquita, João R; Oleastro, Mónica; Penha-Gonçalves, Carlos; Nascimento, Maria S J
2015-07-01
Gastroenteritis is one of the most common infectious diseases in the military populations and can diminish operational effectiveness and impede force readiness. The present study investigates the cause and the source of an acute gastroenteritis outbreak that occurred during a military exercise of the Portuguese Army, in February 2013. A retrospective investigation was performed and stool samples, food items and water were screened for common foodborne bacteria and viruses, namely Norovirus GI, Norovirus GII, Astrovirus, Rotavirus, Adenovirus and Sapovirus. From the total of 160 soldiers that participated in the military exercise 20 developed gastroenteritis (attack rate of 12.5%). Symptoms were predominantly vomiting (n=17, 85%) and diarrhoea (n=9, 45%). The first cases occurred 24-48h after drinking water from the creek, the plausible origin of the outbreak. The epidemic peak was registered 2 days after and the last cases 6 days after, upon returning to base. No pathogenic bacteria were found in stools however virological analysis revealed the presence of multiple enteropathogenic viruses, namely Norovirus GI (GI.3), Norovirus GII (GII.4 New Orleans 2009), Astrovirus and Sapovirus, as single or co-infections. Food and water samples were not tested for the presence of viruses due to exhaustion of samples on bacteriological analysis. To the best of our knowledge this is the first report of a viral gastroenteritis outbreak among military personnel in the Portuguese Army. Copyright © 2015 Elsevier B.V. All rights reserved.
Winter sports athletes: long-term effects of cold air exposure.
Sue-Chu, Malcolm
2012-05-01
Athletes such as skaters and skiers inhale large volumes of cold air during exercise and shift from nasal to mouth breathing. Endurance athletes, like cross-country skiers, perform at 80% or more of their maximal oxygen consumption and have minute ventilations in excess of 100 l/min. Cold air is always dry, and endurance exercise results in loss of water and heat from the lower respiratory tract. In addition, athletes can be exposed to indoor and outdoor pollutants during the competitive season and during all-year training. Hyperpnoea with cold dry air represents a significant environmental stress to the airways. Winter athletes have a high prevalence of respiratory symptoms and airway hyper-responsiveness to methacholine and hyperpnoea. The acute effects of exercise in cold air are neutrophil influx as demonstrated in lavage fluid and airway epithelial damage as demonstrated by bronchoscopy. Upregulation of pro-inflammatory cytokines has been observed in horses. Chronic endurance training damages the epithelium of the small airways in mice. Airway inflammation has been observed on bronchoscopy of cross-country skiers and in dogs after a 1100-mile endurance race in Alaska. Neutrophilic and lymphocytic inflammation with remodelling is present in bronchial biopsies from skiers. Repeated peripheral airway hyperpnoea with dry air causes inflammation and remodelling in dogs. As it is currently unknown if these airway changes are reversible upon cessation of exposure, preventive measures to diminish exposure of the lower airways to cold air should be instituted by all winter sports athletes.
Exercise immunology: practical applications.
Nieman, D C
1997-03-01
During the last 95 years, 629 papers (60% in the 1990s) dealing specifically with exercise and immunology have been published. Major findings of practical importance in terms of public health and athletic endeavor include: (a) In response to acute exercise (the most frequently studied area of exercise immunology), a rapid interchange of immune cells between peripheral lymphoid tissues and the circulation occurs. The response depends on many factors, including the intensity, duration, and mode of exercise, concentrations of hormones and cytokines, change in body temperature, blood flow, hydration status, and body position. Of all immune cells, natural killer (NK) cells, neutrophils, and macrophages (of the innate immune system) appear to be most responsive to the effects of acute exercise, both in terms of numbers and function. In general, acute exercise bouts of moderate duration (< 60 min) and intensity (< 60% VO2max) are associated with fewer perturbations and less stress to the immune system than are prolonged, high-intensity sessions. (b) In response to long-term exercise training, the only finding to date reported with some congruity between investigators is a significant elevation in NK cell activity. Changes in the function of neutrophils, macrophages, and T and B cells in response to training have been reported inconsistently, but there is some indication that neutrophil function is suppressed during periods of heavy training. (c) Limited data suggest that unusually heavy acute or chronic exercise may increase the risk of upper respiratory tract infection (URTI), while regular moderate physical activity may reduce URTI symptomatology. (d) Work performance tends to diminish with most systemic infectious, and clinical case studies and animal data suggest that infection severity, relapse, and myocarditis may result when patients exercise vigorously. (e) Although regular exercise has many benefits for HIV-infected individuals, helper T cell counts and other immune measures are not enhanced significantly. (f) Data suggest that the incidence and mortality rates for certain types of cancer are lower among active subjects. The role of the immune system may be limited, however, depending on the sensitivity of the specific tumor to cytolysis, the stage of cancer, the type of exercise program, and many other complex factors. (g) As individuals age, they experience a decline in most cell- mediated and humoral immune responses. Two human studies suggest that immune function is superior in highly conditioned versus sedentary elderly subjects. (h) Mental stress, undernourishment, quick weight loss, and improper hygiene have each been associated with impaired immunity. Athletes who are undergoing heavy training regimens should realize that each of these factors has the potential to compound the effect that exercise stress is having on their immune systems.
Exercise as an intervention to improve metabolic outcomes after intrauterine growth restriction.
Gatford, Kathryn L; Kaur, Gunveen; Falcão-Tebas, Filippe; Wadley, Glenn D; Wlodek, Mary E; Laker, Rhianna C; Ebeling, Peter R; McConell, Glenn K
2014-05-01
Individuals born after intrauterine growth restriction (IUGR) are at an increased risk of developing diabetes in their adult life. IUGR impairs β-cell function and reduces β-cell mass, thereby diminishing insulin secretion. IUGR also induces insulin resistance, with impaired insulin signaling in muscle in adult humans who were small for gestational age (SGA) and in rodent models of IUGR. There is epidemiological evidence in humans that exercise in adults can reduce the risk of metabolic disease following IUGR. However, it is not clear whether adult IUGR individuals benefit to the same extent from exercise as do normal-birth-weight individuals, as our rat studies suggest less of a benefit in those born IUGR. Importantly, however, there is some evidence from studies in rats that exercise in early life might be able to reverse or reprogram the long-term metabolic effects of IUGR. Studies are needed to address gaps in current knowledge, including determining the mechanisms involved in the reprogramming effects of early exercise in rats, whether exercise early in life or in adulthood has similar beneficial metabolic effects in larger animal models in which insulin resistance develops after IUGR. Human studies are also needed to determine whether exercise training improves insulin secretion and insulin sensitivity to the same extent in IUGR adults as in control populations. Such investigations will have implications for customizing the recommended level and timing of exercise to improve metabolic health after IUGR.
Colditz, Graham A.; Rock, Cheryl L.; Sedjo, Rebecca L.; Liu, Jingxia; Wolin, Kathleen Y.; Krontiras, Helen; Byers, Tim; Pakiz, Bilgé; Parker, Barbara A.; Naughton, Michael; Elias, Anthony; Ganz, Patricia A.
2015-01-01
Obesity is a poor prognostic factor and is negatively related to quality of life (QOL) in breast cancer survivors. Exercise and Nutrition to Enhance Recovery and Good Health for You is the largest weight loss trial completed among cancer survivors. Percent losses in body weight with an intensive group-based intervention versus an attention control were 6.0 versus 1.5 % (p < 0.0001) and 3.7 versus 1.3 % (p<0.0001) at 12 and 24 months, respectively. ENERGY also was designed to answer the research question: Does weight loss significantly improve vitality and physical function (key components of QOL)? 692 breast cancer survivors (BMI: 25–45 kg/m2) at 4 US sites were randomized to a year-long intensive intervention of 52 group sessions and telephone counseling contacts versus a non-intensive (control) of two in-person counseling sessions. Weight, self-reported QOL, and symptoms were measured semi-annually for two years. Significant decreases in physical function and increases in symptoms were observed among controls from baseline to 6 months, but not in the intervention arm, −3.45 (95 % Confidence Interval [CI] −6.10, –0.79, p = 0.0109) and 0.10 (95 %CI 0.04, 0.16, p = 0.0021), respectively. Improvements in vitality were seen in both arms but trended toward greater improvement in the intervention arm −2.72 (95 % CI −5.45, 0.01, p = 0.0508). These differences diminished over time; however, depressive symptoms increased in the intervention versus control arms and became significant at 24 months, −1.64 (95 % CI −3.13, –0.15, p = 0.0308). Increased QOL has been reported in shorter term diet and exercise trials among cancer survivors. These longer term data suggest that diet and exercise interventions improve some aspects of QOL, but these benefits may diminish over time. PMID:26518022
Kuznetsova, Tatiana; D’hooge, Jan; Kloch-Badelek, Malgorzata; Sakiewicz, Wojciech; Thijs, Lutgarde; Staessen, Jan A.
2013-01-01
Background To understand better the mechanism of left ventricular (LV) remodeling related to hypertension, it is important to evaluate LV function in relation to the changes in loading conditions. The aim of this study was to investigate changes in conventional ventricular-arterial coupling indexes, LV strain, and a new index reflecting regional myocardial work assessed noninvasively at rest and during isometric exercise in a random sample including participants with normal blood pressure and those with hypertension. Methods A total of 148 participants (53.4% women; mean age, 52.0 years; 39.2% with hypertension) underwent simultaneous echocardiographic and arterial data acquisition at rest and during increased afterload (handgrip exercise). End-systolic pressure was determined from the carotid pulse wave. Arterial elastance (Ea) and LV elastance (Ees) were calculated as end-systolic pressure/stroke volume and end-systolic pressure/end-systolic volume. Doppler tissue imaging and two-dimensional speckle tracking were used to derive LV longitudinal strain. Regional myocardial work (ejection work density [EWD]) was the area of the pressure-strain loop during ejection. Results At rest, with adjustments applied, Ees (3.06 vs 3.71 mmHg/mL,P = .0003), Ea/Ees (0.54 vs 0.47,P=.002) and EWD (670 vs 802 Pa/m2, P = .0001) differed significantly between participants with normal blood pressure and those with hypertension. During handgrip exercise, Ea and Ea/Ees significantly increased (P < .0001) in both groups. Doppler tissue imaging and two-dimensional LV strain decreased in participants with hypertension (P ≤ .008). Only in subjects with normal blood pressure EWD significantly increased (+14.7%, P = .0009). Conclusions Although patients with hypertension compared with those with normal blood pressure have increased LV systolic stiffness and regional myocardial work to match arterial load at rest, they might have diminished cardiac reserve to increase myocardial performance, as estimated by EWD during isometric exercise. PMID:22622108
Parkin is required for exercise-induced mitophagy in muscle: impact of aging.
Chen, Chris Chin Wah; Erlich, Avigail T; Crilly, Matthew J; Hood, David A
2018-05-29
The maintenance of muscle health with advancing age is dependent on mitochondrial homeostasis. While reductions in mitochondrial biogenesis have been observed with age, less is known regarding organelle degradation. Parkin is an E3 ubiquitin ligase implicated in mitophagy, but few studies have examined Parkin's contribution to mitochondrial turnover in muscle. Wild type (WT) and Parkin knockout (KO) mice were used to delineate a role for Parkin-mediated mitochondrial degradation in aged muscle, in concurrence with exercise. Aged animals exhibited declines in muscle mass and mitochondrial content, paralleled by a nuclear environment endorsing the transcriptional repression of mitochondrial biogenesis. Mitophagic signaling was enhanced following acute endurance exercise in young WT mice, but was abolished in the absence of Parkin. Basal mitophagy flux of the autophagosomal protein LC3II was augmented in aged animals, but did not increase additionally with exercise when compared to young animals. In the absence of Parkin, exercise increased the nuclear localization of PARIS, corresponding to a decrease in nuclear PGC-1α. Remarkably, exercise enhanced mitochondrial ubiquitination in both young WT and KO animals. This suggested compensation of alternative ubiquitin ligases that were, however, unable to restore the diminished exercise-induced mitophagy in KO mice. Under basal conditions, we demonstrated that Parkin was required for mitochondrial Mfn2 ubiquitination. We also observed an abrogation of exercise-induced mitophagy in aged muscle. Our results demonstrate that acute exercise-induced mitophagy is dependent on Parkin, and attenuated with age, which likely contributes to changes in mitochondrial content and quality in aging muscle.
Barrett-O'Keefe, Zachary; Lee, Joshua F.; Berbert, Amanda; Witman, Melissa A. H.; Nativi-Nicolau, Jose; Stehlik, Josef; Richardson, Russell S.
2014-01-01
To better understand the mechanisms responsible for exercise intolerance in heart failure with reduced ejection fraction (HFrEF), the present study sought to evaluate the hemodynamic responses to small muscle mass exercise in this cohort. In 25 HFrEF patients (64 ± 2 yr) and 17 healthy, age-matched control subjects (64 ± 2 yr), mean arterial pressure (MAP), cardiac output (CO), and limb blood flow were examined during graded static-intermittent handgrip (HG) and dynamic single-leg knee-extensor (KE) exercise. During HG exercise, MAP increased similarly between groups. CO increased significantly (+1.3 ± 0.3 l/min) in the control group, but it remained unchanged across workloads in HFrEF patients. At 15% maximum voluntary contraction (MVC), forearm blood flow was similar between groups, while HFrEF patients exhibited an attenuated increase at the two highest intensities compared with controls, with the greatest difference at the highest workload (352 ± 22 vs. 492 ± 48 ml/min, HFrEF vs. control, 45% MVC). During KE exercise, MAP and CO increased similarly across work rates between groups. However, HFrEF patients exhibited a diminished leg hyperemic response across all work rates, with the most substantial decrement at the highest intensity (1,842 ± 64 vs. 2,675 ± 81 ml/min; HFrEF vs. control, 15 W). Together, these findings indicate a marked attenuation in exercising limb perfusion attributable to impairments in peripheral vasodilatory capacity during both arm and leg exercise in patients with HFrEF, which likely plays a role in limiting exercise capacity in this patient population. PMID:25260608
Cannell, L; Taunton, J; Clement, D; Smith, C; Khan, K
2001-01-01
Objectives—To compare the therapeutic effect of two different exercise protocols in athletes with jumper's knee. Methods—Randomised clinical trial comparing a 12 week programme of either drop squat exercises or leg extension/leg curl exercises. Measurement was performed at baseline and after six and 12 weeks. Primary outcome measures were pain (visual analogue scale 1–10) and return to sport. Secondary outcome measures included quadriceps and hamstring moment of force using a Cybex II isokinetic dynamometer at 30°/second. Differences in pain response between the drop squat and leg extension/curl treatment groups were assessed by 2 (group) x 3 (time) analysis of variance. Two by two contingency tables were used to test differences in rates of return to sport. Analysis of variance (2 (injured versus non-injured leg) x 2 (group) x 3 (time)) was also used to determine differences for secondary outcome measures. Results—Over the 12 week intervention, pain diminished by 2.3 points (36%) in the leg extension/curl group and 3.2 points (57%) in the squat group. There was a significant main effect of both exercise protocols on pain (p<0.01) with no interaction effect. Nine of 10 subjects in the drop squat group returned to sporting activity by 12 weeks, but five of those subjects still had low level pain. Six of nine of the leg extension/curl group returned to sporting activity by 12 weeks and four patients had low level pain. There was no significant difference between groups in numbers returning to sporting activity. There were no differences in the change in quadriceps or hamstring muscle moment of force between groups. Conclusions—Progressive drop squats and leg extension/curl exercises can reduce the pain of jumper's knee in a 12 week period and permit a high proportion of patients to return to sport. Not all patients, however, return to sport by that time. Key Words: knee; patellar tendon; tendinopathy; tendinosis; eccentric strengthening; strength training PMID:11157465
Sweat Facilitated Amino Acid Losses in Male Athletes during Exercise at 32-34°C.
Dunstan, R Hugh; Sparkes, Diane L; Dascombe, Benjamin J; Macdonald, Margaret M; Evans, Craig A; Stevens, Christopher J; Crompton, Marcus J; Gottfries, Johan; Franks, Jesse; Murphy, Grace; Wood, Ryan; Roberts, Timothy K
2016-01-01
Sweat contains amino acids and electrolytes derived from plasma and athletes can lose 1-2L of sweat per hour during exercise. Sweat may also contain contributions of amino acids as well as urea, sodium and potassium from the natural moisturizing factors (NMF) produced in the stratum corneum. In preliminary experiments, one participant was tested on three separate occasions to compare sweat composition with surface water washings from the same area of skin to assess contributions from NMF. Two participants performed a 40 minute self-paced cycle session with sweat collected from cleansed skin at regular intervals to assess the contributions to the sweat load from NMF over the period of exercise. The main study investigated sweat amino acid composition collected from nineteen male athletes following standardised endurance exercise regimes at 32-34°C and 20-30% RH. Plasma was also collected from ten of the athletes to compare sweat and plasma composition of amino acids. The amino acid profiles of the skin washings were similar to the sweat, suggesting that the NMF could contribute certain amino acids into sweat. Since the sweat collected from athletes contained some amino acid contributions from the skin, this fluid was subsequently referred to as "faux" sweat. Samples taken over 40 minutes of exercise showed that these contributions diminished over time and were minimal at 35 minutes. In the main study, the faux sweat samples collected from the athletes with minimal NMF contributions, were characterised by relatively high levels of serine, histidine, ornithine, glycine and alanine compared with the corresponding levels measured in the plasma. Aspartic acid was detected in faux sweat but not in the plasma. Glutamine and proline were lower in the faux sweat than plasma in all the athletes. Three phenotypic groups of athletes were defined based on faux sweat volumes and composition profiles of amino acids with varying relative abundances of histidine, serine, glycine and ornithine. It was concluded that for some individuals, faux sweat resulting from exercise at 32-34°C and 20-30% RH posed a potentially significant source of amino acid loss.
Sweat Facilitated Amino Acid Losses in Male Athletes during Exercise at 32-34°C
Dunstan, R. Hugh; Sparkes, Diane L.; Dascombe, Benjamin J.; Macdonald, Margaret M.; Evans, Craig A.; Stevens, Christopher J.; Crompton, Marcus J.; Gottfries, Johan; Franks, Jesse; Murphy, Grace; Wood, Ryan; Roberts, Timothy K.
2016-01-01
Sweat contains amino acids and electrolytes derived from plasma and athletes can lose 1-2L of sweat per hour during exercise. Sweat may also contain contributions of amino acids as well as urea, sodium and potassium from the natural moisturizing factors (NMF) produced in the stratum corneum. In preliminary experiments, one participant was tested on three separate occasions to compare sweat composition with surface water washings from the same area of skin to assess contributions from NMF. Two participants performed a 40 minute self-paced cycle session with sweat collected from cleansed skin at regular intervals to assess the contributions to the sweat load from NMF over the period of exercise. The main study investigated sweat amino acid composition collected from nineteen male athletes following standardised endurance exercise regimes at 32–34°C and 20–30% RH. Plasma was also collected from ten of the athletes to compare sweat and plasma composition of amino acids. The amino acid profiles of the skin washings were similar to the sweat, suggesting that the NMF could contribute certain amino acids into sweat. Since the sweat collected from athletes contained some amino acid contributions from the skin, this fluid was subsequently referred to as “faux” sweat. Samples taken over 40 minutes of exercise showed that these contributions diminished over time and were minimal at 35 minutes. In the main study, the faux sweat samples collected from the athletes with minimal NMF contributions, were characterised by relatively high levels of serine, histidine, ornithine, glycine and alanine compared with the corresponding levels measured in the plasma. Aspartic acid was detected in faux sweat but not in the plasma. Glutamine and proline were lower in the faux sweat than plasma in all the athletes. Three phenotypic groups of athletes were defined based on faux sweat volumes and composition profiles of amino acids with varying relative abundances of histidine, serine, glycine and ornithine. It was concluded that for some individuals, faux sweat resulting from exercise at 32–34°C and 20–30% RH posed a potentially significant source of amino acid loss. PMID:27936120
Sazontova, T G; Glazachev, O S; Bolotova, A V; Dudnik, E N; Striapko, N V; Bedareva, I V; Anchishkina, N A; Arkhipenko, Iu V
2012-06-01
We have conducted theoretical foundation, experimental analysis and a pilot study of a new method of adaptation to hypoxia and hyperoxia in the prevention of hypoxic and stress-induced disorders and improving the body's tolerance to physical stress. It has been shown in the experimental part that a combination of physical exercise with adaptation to hypoxia-hyperoxia significantly increased tolerance to acute physical load (APL) and its active phase. Analysis of lipid peroxidation processes, antioxidant enzymes and HSPs showed that short-term training for physical exercise by itself compensates the stressor, but not the hypoxic component of the APL, the combination of training with adaptation to hypoxia-hyperoxia completely normalizes the stressor and hypoxic components of APL. The pilot study has been performed to evaluate the effectiveness of hypoxic-hyperoxic training course in qualified young athletes with over-training syndrome. After completing the course of hypoxia-hyperoxia adaptation, 14 sessions, accompanied by light mode sports training, the athletes set the normalization of autonomic balance, increased resistance to acute hypoxia in hypoxic test, increased physical performance--increased PWC170, maximal oxygen consumption (VO2max) parameters, their relative values to body mass, diminished shift of rate pressure product in the load. Thus, we confirmed experimental findings that hypoxic-hyperoxic training optimizes hypoxic (increased athletes resistance to proper hypoxia) and stress (myocardium economy in acute physical stress testing) components in systemic adaptation and restoration of athletes' with over-training syndrome.
Karakilcik, A Z; Halat, R; Zerin, M; Celik, H; Nazligul, Y
2014-10-01
Exercise may increase production of reactive oxygen species (ROS) enhancing oxidative stress. Antioxidants can efficiently scavenge ROS before they initiate oxidative damage of biomolecules such as enzymes, nucleic acids, lipids and lipoproteins in the body. Vitamin C, an important antioxidant, may affect oxidative stress in living organism. Therefore, this study was carried out to investigate the effects of exercise and vitamin C on thiobarbituric acid-reactive substance (TBARS), lipid profile, erythrocyte and platelet indices in young soccer players. This investigation was carried out on twenty two male volunteer players in three groups. The first group was examined as a control. The second group was only exposed to exercise. The third group was exposed to exercise plus vitamin C (500 mg/day) administered per oral. The players were 23.50±0.59 year-old, 67.66±1.52 kg body weight and 1.74±0.03 m height. Blood samples were collected in vacutainer tubes for analysis of biochemical and hematological parameters. While the levels of high density lipoprotein-cholesterol (HDL-C) were significantly increased (P<0.05) with only exercise, the cholesterol and low density lipoprotein-cholesterol (LDL-C) were decreased (P<0.05 to P<0.01) with exercise and exercise plus vitamin C treatment. While TBARS levels were increased (P<0.05) with exercise training, it was decreased (P<0.05) with exercise plus vitamin C treatment. The platelet counts (PLT), mean platelet volume (MPV), plateletcrit (PCT) and red blood cell distribution width (RDW) were significantly decreased (P<0.05) with exercise plus vitamin C. There were significantly correlations (P<0.05 to P<0.01) between lipid values and erythrocyte and platelet indices. In light of these results, exercise may play a role in decreasing of LDL-C and in increasing of HDL-C. In addition, exercise plus vitamin C may diminish TBARS-levels and may affect the values of PLT, MPV, PCT and RDW in young soccer players.
Comparison of three different approaches in the treatment of chronic low back pain.
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.
The Citadel cannot hold: technologies go outside the hospital, patients and doctors too.
Stoeckle, J D
1995-01-01
Use of the acute hospital has markedly decreased over the past four decades for various reasons: the decentralization of diagnostic treatment technologies to out-of-hospital sites; the clinical substitutions of quick diagnostic testing of the ambulatory patient for the longer diagnostic testing of the hospitalized patient; the diminished use of hospital bed rest and the expanded use of exercise for treatment; the corporate organization of hospital work that emphasizes efficiency; and the group practice organization of generalists and specialists that avoids hospital use for the diagnosis of complex disorders in ambulatory patients. A smaller domain for hospital bed care and renewed attention to chronic disease and prevention in the community diminish the hold of the acute hospital on care. The evolution of more collaborative, decentralized arrangements promises to be a positive development for community care.
Delp, Michael D; Armstrong, R B; Godfrey, Donald A; Laughlin, M Harold; Ross, C David; Wilkerson, M Keith
2001-01-01
The purpose of these experiments was to use radiolabelled microspheres to measure blood flow distribution within the brain, and in particular to areas associated with motor function, maintenance of equilibrium, cardiorespiratory control, vision, hearing and smell, at rest and during exercise in miniature swine. Exercise consisted of steady-state treadmill running at intensities eliciting 70 and 100 % maximal oxygen consumption (). Mean arterial pressure was elevated by 17 and 26 % above that at rest during exercise at 70 and 100 %, respectively. Mean brain blood flow increased 24 and 25 % at 70 and 100 %, respectively. Blood flow was not locally elevated to cortical regions associated with motor and somatosensory functions during exercise, but was increased to several subcortical areas that are involved in the control of locomotion. Exercise elevated perfusion and diminished vascular resistance in several regions of the brain related to the maintenance of equilibrium (vestibular nuclear area, cerebellar ventral vermis and floccular lobe), cardiorespiratory control (medulla and pons), and vision (dorsal occipital cortex, superior colliculi and lateral geniculate body). Conversely, blood flow to regions related to hearing (cochlear nuclei, inferior colliculi and temporal cortex) and smell (olfactory bulbs and rhinencephalon) were unaltered by exercise and associated with increases in vascular resistance. The data indicate that blood flow increases as a function of exercise intensity to several areas of the brain associated with integrating sensory input and motor output (anterior and dorsal cerebellar vermis) and the maintenance of equilibrium (vestibular nuclei). Additionally, there was an intensity-dependent decrease of vascular resistance in the dorsal cerebellar vermis. PMID:11410640
Aghdam, Amir Mahmoudi; Shahabi, Parviz; Karimi-Sales, Elham; Ghiasi, Rafigheh; Sadigh-Eteghad, Saeed; Mahmoudi, Javad; Alipour, Mohammad Reza
2018-04-30
Diabetes is a common metabolic disease which leads to diabetic peripheral neuropathy. Recently, the role of microRNA-96 (miR-96) in alleviating neuropathic pain by inhibiting the expression of NaV1.3, an isoform of voltage-gated sodium channels, has been shown. Peripheral nerve injuries result in NaV1.3 elevation. Exercise has beneficial role in diabetes management and peripheral neuropathy. However, the effects of exercise on miR-96 and its target gene NaV1.3 in diabetic rats are unknown. Therefore, the present study investigated the effects of exercise training on the expression of miR-96 and NaV1.3 in diabetic rats. For this purpose, rats were randomly divided into four groups: control, exercise, diabetic and diabetic-exercise groups. Type 2 diabetes was induced by a high-fat diet and the administration of streptozotocin (STZ) (35 mg/kg, i.p.). The exercise groups were subjected to swimming exercise 5 days/week for 10 weeks. At the end of the treatment period, thermal pain threshold, determined through the tail-flick test, and the expression levels of miR-96 and its target gene NaV1.3 were determined by reverse transcription (RT)-PCR in the sciatic nerve tissues of the rats. Data of the present study indicated that diabetes diminished miR-96 expression levels, but significantly upregulated NaV1.3 expression in the sciatic nerve. On exercise training, miR-96 expression was reversed with concurrent down-regulation of the NaV1.3 expression. This study introduced a new and potential miRNA-dependent mechanism for exerciseinduced protective effects against diabetic thermal hyperalgesia.
NASA Astrophysics Data System (ADS)
Petri, Ines; Scherbarth, Frank; Steinlechner, Stephan
2010-09-01
Energy demands of gestation and lactation represent a severe challenge for small mammals. Therefore, additional energetic burdens may compromise successful breeding. In small rodents, food restriction, cold exposure (also in combination) and wheel running to obtain food have been shown to diminish reproductive outcome. Although exhibited responses such as lower incidence of pregnancy, extended lactation periods and maternal infanticide were species dependent, their common function is to adjust energetic costs to the metabolic state reflecting the trade-off between maternal investment and self-maintenance. In the present study, we sought to examine whether voluntary exercise affects reproduction in Djungarian hamsters ( Phodopus sungorus), which are known for their high motivation to run in a wheel. Voluntary exercise resulted in two different effects on reproduction; in addition to increased infanticide and cannibalism, which was evident across all experiments, the results of one experiment provided evidence that free access to a running wheel may prevent successful pregnancy. It seems likely that the impact of voluntary wheel running on reproduction was associated with a reduction of internal energy resources evoked by extensive exercise. Since the hamsters were neither food-restricted nor forced to run in the present study, an energetic deficit as reason for infanticide in exercising dams would emphasise the particularly high motivation to run in a wheel.
Lack of diurnal effects on periodic exercise during prolonged cold water immersion.
Doubt, T J; Smith, D J
1990-03-01
Diurnal effects on periodic exercise were examined in 8 male divers wearing passive thermal protection during whole body immersions in 5 degrees C water for periods of up to 6 h. Studies were done during the course of 5-day air saturation dives at a depth of 1.61 ATA, with immersions beginning at 1000 h (AM) and 2200 h (PM). During each hour of immersion, leg exercise was done for 3 min each at workloads of 50, 70, and 90 W. Heart rate (HR) at each workload increased uniformly with immersion time, without a change in slope of HR vs. workload. No AM or PM differences occurred. AM resting VO2 increased linearly, and to the same extent as PM, with exposure time. VO2 at 50 W also increased at the same rate as resting values. VO2 at 70 and 90 W were similar for AM and PM and did not vary significantly during the 6-h immersions. Temporal increases in exercise HR may reflect cardiac compensation of diminished plasma volume. Workloads greater than or equal to 70 W generate enough metabolic heat in this specific condition to meet the thermogenic requirement. Lack of diurnal effects on exercise variables may be due to environmental conditions suppressing circadian rhythms.
Ekici, Gamze; Unal, Edibe; Akbayrak, Turkan; Vardar-Yagli, Naciye; Yakut, Yavuz; Karabulut, Erdem
2017-01-01
The authors of this study compared the effects of pilates exercises and connective tissue massage (CTM) on pain intensity; pain-pressure threshold; and tolerance, anxiety, progress, and health-related quality of life in females with fibromyalgia. It was a pilot, assessor masked, randomized controlled trial conducted between January and August of 2013. Twenty-one women with fibromyalgia were randomly assigned to the pilates exercise program (six of whom did not complete the program), and 22 were randomly assigned to CTM (one of whom did not complete this program). Each group received the assigned intervention three times per week during a 4-week period. The Visual Analogue Scale, algometry, State-Trait Anxiety Inventory, Fibromyalgia Impact Questionnaire, and Nottingham Health Profile were used at baseline and at the end of treatments. Significant improvements were found in both groups for all parameters. However, the scores for pain-pressure threshold were significantly elevated and the symptoms of anxiety were significantly diminished in the exercise group compared to the massage group. Thus, exercise and massage might be used to provide improvements in women with fibromyalgia. The exercise group showed more advantages than the massage group and thus might be preferred for patients with fibromyalgia. However, an adequately powered trial is required to determine this with certainty.
Young girl presenting with exercise-induced myoglobinuria.
Krishnaiah, Balaji; Lee, Jennifer Jheesoo; Wicklund, Matthew Paul; Kaur, Divpreet
2016-06-01
The sarcoglycanopathies are a heterogeneous group of autosomal recessive limb-girdle muscular dystrophies that cause varying degrees of progressive proximal muscle weakness. We describe the case of a Caucasian girl who presented with exercise intolerance, myalgia, and dark urine. Onset of symptoms was at age 4, and she had myalgia with physical activity throughout childhood. Creatine kinase levels were as high as 18,000. Immunostaining of a muscle biopsy showed mildly diminished alpha sarcoglycan staining, and SGCA gene sequencing revealed n.C229T; p.Arg77Cys (R77C) and n.C850T; p.Arg284Cys (R284C), which is associated with alpha sarcoglycanopathy. This patient presented with exercise intolerance, myoglobinuria, and almost normal muscle strength into adolescence, which is uncommon in sarcoglycanopathies. This uncommon presentation should be kept in mind, so that early recognition and intervention may prevent future comorbidities and help preserve the quality of life. Muscle Nerve 54: 161-164, 2016. © 2016 Wiley Periodicals, Inc.
Health investment decisions in response to diabetes information in older Americans.
Slade, Alexander N
2012-05-01
Diabetes is a very common and serious chronic disease, and one of the fastest growing disease burdens in the United States. Further, health behaviors, such as exercise, smoking, drinking, as well as weight status, are instrumental to diabetes management and the reduction of its medical consequences. Nine waves of the Health and Retirement Study are used to model the role of a recent diabetes diagnosis and medication on present and subsequent weight status, exercise, drinking and smoking activity. Several non-linear dynamic population average probit models are estimated. Results suggest that compared to non-diagnosed individuals at risk for high blood sugar, diagnosed diabetics respond initially in terms of increasing exercise, losing weight, and curbing smoking and drinking behavior, but the effect diminishes after diagnosis. Evidence of recidivism is also found in these outcomes, especially weight status and physical activity, suggesting that some behavioral responses to diabetes may be short-lived. Copyright © 2012 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Lee, S. M. C.; Streeper, T.; Spiering, B. A.; Loehr, J. A.; Guilliams, M. E.; Bloomberg, J. J.; Mulavara, A. P.; Cavanagh, P. R.; Lang, T.
2010-01-01
Musculoskeletal, cardiovascular, and sensorimotor deconditioning have been observed consistently in astronauts and cosmonauts following long-duration spaceflight. Studies in bed rest, a spaceflight analog, have shown that high intensity resistive or aerobic exercise attenuates or prevents musculoskeletal and cardiovascular deconditioning, respectively, but complete protection has not been achieved during spaceflight. Exercise countermeasure hardware used during earlier International Space Station (ISS) missions included a cycle ergometer, a treadmill, and the interim resistive exercise device (iRED). Effectiveness of the countermeasures may have been diminished by limited loading characteristics of the iRED as well as speed restrictions and subject harness discomfort during treadmill exercise. The Advanced Resistive Exercise Device (ARED) and the second generation treadmill were designed to address many of the limitations of their predecessors, and anecdotal reports from ISS crews suggest that their conditioning is better preserved since the new hardware was delivered in 2009. However, several countermeasure devices to protect different physiologic systems will not be practical during exploration missions when the available volume and mass will be severely restricted. The combined countermeasure device (CCD) integrates a suite of hardware into one device intended to prevent spaceflight-induced musculoskeletal, cardiovascular, and sensorimotor deconditioning. The CCD includes pneumatic loading devices with attached cables for resistive exercise, a cycle for aerobic exercise, and a 6 degree of freedom motion platform for balance training. In a proof of concept test, ambulatory untrained subjects increased muscle strength (58%) as well as aerobic capacity (26%) after 12-weeks of exercise training with the CCD (without balance training), improvements comparable to those observed with traditional exercise training. These preliminary results suggest that this CCD can concurrently improve musculoskeletal and cardiovascular conditioning in ambulatory subjects, but further work is required to validate its use as countermeasure to spaceflight-induced deconditioning.
Aird, T P; Davies, R W; Carson, B P
2018-05-01
The effects of nutrition on exercise metabolism and performance remain an important topic among sports scientists, clinical, and athletic populations. Recently, fasted exercise has garnered interest as a beneficial stimulus which induces superior metabolic adaptations to fed exercise in key peripheral tissues. Conversely, pre-exercise feeding augments exercise performance compared with fasting conditions. Given these seemingly divergent effects on performance and metabolism, an appraisal of the literature is warranted. This review determined the effects of fasting vs pre-exercise feeding on continuous aerobic and anaerobic or intermittent exercise performance, and post-exercise metabolic adaptations. A search was performed using the MEDLINE and PubMed search engines. The literature search identified 46 studies meeting the relevant inclusion criteria. The Delphi list was used to assess study quality. A meta-analysis and meta-regression were performed where appropriate. Findings indicated that pre-exercise feeding enhanced prolonged (P = .012), but not shorter duration aerobic exercise performance (P = .687). Fasted exercise increased post-exercise circulating FFAs (P = .023) compared to fed exercise. It is evidenced that pre-exercise feeding blunted signaling in skeletal muscle and adipose tissue implicated in regulating components of metabolism, including mitochondrial adaptation and substrate utilization. This review's findings support the hypothesis that the fasted and fed conditions can divergently influence exercise metabolism and performance. Pre-exercise feeding bolsters prolonged aerobic performance, while seminal evidence highlights potential beneficial metabolic adaptations that fasted exercise may induce in peripheral tissues. However, further research is required to fully elucidate the acute and chronic physiological adaptations to fasted vs fed exercise. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Rooney, Sarah Ilkhanipour; Baskin, Rachel; Torino, Daniel J; Vafa, Rameen P; Khandekar, Pooja S; Kuntz, Andrew F; Soslowsky, Louis J
2016-09-01
Previous studies have shown that ibuprofen is detrimental to tissue healing after acute injury; however, the effects of ibuprofen when combined with noninjurious exercise are debated. Administration of ibuprofen to rats undergoing a noninjurious treadmill exercise protocol will abolish the beneficial adaptations found with exercise but will have no effect on sedentary muscle and tendon properties. Controlled laboratory study. A total of 167 male Sprague-Dawley rats were divided into exercise or cage activity (sedentary) groups and acute (a single bout of exercise followed by 24 hours of rest) and chronic (2 or 8 weeks of repeated exercise) response times. Half of the rats were administered ibuprofen to investigate the effects of this drug over time when combined with different activity levels (exercise and sedentary). Supraspinatus tendons were used for mechanical testing and histologic assessment (organization, cell shape, cellularity), and supraspinatus muscles were used for morphologic (fiber cross-sectional area, centrally nucleated fibers) and fiber type analysis. Chronic intake of ibuprofen did not impair supraspinatus tendon organization or mechanical adaptations (stiffness, modulus, maximum load, maximum stress, dynamic modulus, or viscoelastic properties) to exercise. Tendon mechanical properties were not diminished and in some instances increased with ibuprofen. In contrast, total supraspinatus muscle fiber cross-sectional area decreased with ibuprofen at chronic response times, and some fiber type-specific changes were detected. Chronic administration of ibuprofen does not impair supraspinatus tendon mechanical properties in a rat model of exercise but does decrease supraspinatus muscle fiber cross-sectional area. This fundamental study adds to the growing literature on the effects of ibuprofen on musculoskeletal tissues and provides a solid foundation on which future work can build. The study findings suggest that ibuprofen does not detrimentally affect regulation of supraspinatus tendon adaptations to exercise but does decrease muscle growth. Individuals should be advised on the risk of decreased muscle hypertrophy when consuming ibuprofen. © 2016 The Author(s).
Leak, Rehana K.; Garbett, Krassimira A.; Dettmer, Amanda M.; Zhang, Zhiming; Mirnics, Károly; Cameron, Judy L.
2013-01-01
Ceruloplasmin is a protective ferroxidase. Although some studies suggest that plasma ceruloplasmin levels are raised by exercise, the impact of exercise on brain ceruloplasmin is unknown. The present study examined whether striatal ceruloplasmin is raised with treadmill exercise and/or is correlated with spontaneous physical activity in rhesus monkeys. Parkinson’s disease is characterized by a loss in ceruloplasmin and, similarly, Parkinson’s models lead to a loss in antioxidant defenses. Exercise may protect against Parkinson’s disease and is known to prevent antioxidant loss in experimental models. We therefore examined whether treadmill exercise prevents ceruloplasmin loss in monkeys treated unilaterally with the dopaminergic neurotoxin MPTP. We found that exercise raised ceruloplasmin expression in the caudate and accumbens, but not the putamen of intact monkeys. However, putamen ceruloplasmin was correlated with spontaneous activity in a home pen. MPTP alone did not cause unilateral loss of ceruloplasmin but blocked the impact of exercise on ceruloplasmin. Similarly, the correlation between putamen ceruloplasmin and activity was also lost with MPTP. MPTP elicited loss of tyrosine hydroxylase in the treated hemisphere and the remaining tyrosine hydroxylase was correlated with overall daily activity (spontaneous activity plus that induced by the treadmill). These data reveal that treadmill activity can raise ceruloplasmin, but that this impact and the link with spontaneous activity are both diminished in parkinsonian primates. Furthermore, low overall physical activity predicts greater loss of dopaminergic phenotype in MPTP-treated primates. These data have implications for the maintenance of active lifestyles in both healthy and neurodegenerative conditions. PMID:22940761
Beinert, Konstantin; Sofsky, Marc; Trojan, Jörg
2018-05-09
Sensorimotor tests, like cranio- cervical flexion and cervical joint position sense tests, share a strong cognitive component during their execution. However, cognitive training for those tests has not been investigated so far. To compare mental and physical exercises for improving the sensorimotor function of the cervical spine. A within-subject design with 16 participants. Outpatient physiotherapy centre. Patients with chronic neck pain. Participants were instructed to perform specific active or mental exercises for the deep and superficial neck flexor muscles. The primary outcomes were cranio-cervical flexion test performance, postural sway, cervical joint position sense and pressure pain threshold. A mixed model analysis was used. The interventions improved cranio-cervical flexion performance (p < 0.001), with no difference between actively or mentally performed exercises. Postural sway increased after actively (p < 0.01) and mentally (p < 0.05) performed deep cervical neck flexor exercises, but not after superficial neck flexor exercises. Mentally performed superficial neck flexor exercises improved cervical joint position sense when compared to mentally performed deep cervical flexor exercises (p < 0.05), and actively performed superficial neck flexor exercises were effective in improving cervical joint position sense acuity compared to mentally performed deep cervical flexor exercises (p < 0.05) for relocation tasks in the transverse plane. The pressure pain threshold at the cervical spine increased after active deep cervical flexor exercises (p < 0.05) and after mental superficial neck flexor exercise (p < 0.05). Mentally performed deep cervical flexor exercises improved cranio-cervical flexion test performance, postural sway and pressure pain threshold at the cervical spine. Mentally performed superficial neck flexor exercises improved cervical joint position sense acuity more than mentally performed deep cervical flexor exercises. Mentally performed exercises are recommended in the early stages of rehabilitation to counteract extensive muscle impairment, and these can be incorporated into daily routine.
Exercise Performance and Corticospinal Excitability during Action Observation
Wrightson, James G.; Twomey, Rosie; Smeeton, Nicholas J.
2016-01-01
Purpose: Observation of a model performing fast exercise improves simultaneous exercise performance; however, the precise mechanism underpinning this effect is unknown. The aim of the present study was to investigate whether the speed of the observed exercise influenced both upper body exercise performance and the activation of a cortical action observation network (AON). Method: In Experiment 1, 10 participants completed a 5 km time trial on an arm-crank ergometer whilst observing a blank screen (no-video) and a model performing exercise at both a typical (i.e., individual mean cadence during baseline time trial) and 15% faster than typical speed. In Experiment 2, 11 participants performed arm crank exercise whilst observing exercise at typical speed, 15% slower and 15% faster than typical speed. In Experiment 3, 11 participants observed the typical, slow and fast exercise, and a no-video, whilst corticospinal excitability was assessed using transcranial magnetic stimulation. Results: In Experiment 1, performance time decreased and mean power increased, during observation of the fast exercise compared to the no-video condition. In Experiment 2, cadence and power increased during observation of the fast exercise compared to the typical speed exercise but there was no effect of observation of slow exercise on exercise behavior. In Experiment 3, observation of exercise increased corticospinal excitability; however, there was no difference between the exercise speeds. Conclusion: Observation of fast exercise improves simultaneous upper-body exercise performance. However, because there was no effect of exercise speed on corticospinal excitability, these results suggest that these improvements are not solely due to changes in the activity of the AON. PMID:27014037
p53 improves aerobic exercise capacity and augments skeletal muscle mitochondrial DNA content.
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.
NASA Technical Reports Server (NTRS)
Delp, M. D.; Armstrong, R. B.; Godfrey, D. A.; Laughlin, M. H.; Ross, C. D.; Wilkerson, M. K.
2001-01-01
1. The purpose of these experiments was to use radiolabelled microspheres to measure blood flow distribution within the brain, and in particular to areas associated with motor function, maintenance of equilibrium, cardiorespiratory control, vision, hearing and smell, at rest and during exercise in miniature swine. Exercise consisted of steady-state treadmill running at intensities eliciting 70 and 100 % maximal oxygen consumption (V(O(2),max)). 2. Mean arterial pressure was elevated by 17 and 26 % above that at rest during exercise at 70 and 100 % V(O(2),max), respectively. 3. Mean brain blood flow increased 24 and 25 % at 70 and 100 % V(O(2),max), respectively. Blood flow was not locally elevated to cortical regions associated with motor and somatosensory functions during exercise, but was increased to several subcortical areas that are involved in the control of locomotion. 4. Exercise elevated perfusion and diminished vascular resistance in several regions of the brain related to the maintenance of equilibrium (vestibular nuclear area, cerebellar ventral vermis and floccular lobe), cardiorespiratory control (medulla and pons), and vision (dorsal occipital cortex, superior colliculi and lateral geniculate body). Conversely, blood flow to regions related to hearing (cochlear nuclei, inferior colliculi and temporal cortex) and smell (olfactory bulbs and rhinencephalon) were unaltered by exercise and associated with increases in vascular resistance. 5. The data indicate that blood flow increases as a function of exercise intensity to several areas of the brain associated with integrating sensory input and motor output (anterior and dorsal cerebellar vermis) and the maintenance of equilibrium (vestibular nuclei). Additionally, there was an intensity-dependent decrease of vascular resistance in the dorsal cerebellar vermis.
Rico-Sanz, J; Rankinen, T; Joanisse, D R; Leon, A S; Skinner, J S; Wilmore, J H; Rao, D C; Bouchard, C
2003-07-07
The associations of the C34T polymorphism of the adenosine monophosphate deaminase 1 (AMPD1) gene with cardiorespiratory phenotypes were tested during cycling exercise at absolute and relative power outputs progressing to exhaustion before and after endurance training for 20 wk in the HERITAGE Family Study cohort (n = 779). Since no blacks were mutant homozygotes (TT), only whites were considered for analysis (400 normal homozygotes, CC; 97 heterozygotes, CT; and 6 TT). For sedentary state, cycling at the absolute power output of 50 W resulted in a higher rating of perceived exertion in TT (P < 0.0001). At the relative intensity of 60% of Vo(2 max), stroke volume was lower in TT (P < 0.05). Maximal values for power output, systolic blood pressure, heart rate, Vco(2), and respiratory exchange ratio were lower in TT (P < 0.05). The cardiorespiratory training response at 50 W and at 60% of Vo(2 max) was similar across C34T-AMPD1 genotypes. However, the maximal values for ventilation, Vo(2), and Vco(2) during exercise increased less in TT (P < 0.01). The results indicate that subjects with the TT genotype at the C34T AMPD1 gene have diminished exercise capacity and cardiorespiratory responses to exercise in the sedentary state. Furthermore, the training response of ventilatory phenotypes during maximal exercise is more limited in TT.
Borer, Katarina T
2005-01-01
Osteoporosis is a serious health problem that diminishes quality of life and levies a financial burden on those who fear and experience bone fractures. Physical activity as a way to prevent osteoporosis is based on evidence that it can regulate bone maintenance and stimulate bone formation including the accumulation of mineral, in addition to strengthening muscles, improving balance, and thus reducing the overall risk of falls and fractures. Currently, our understanding of how to use exercise effectively in the prevention of osteoporosis is incomplete. It is uncertain whether exercise will help accumulate more overall peak bone mass during childhood, adolescence and young adulthood. Also, the consistent effectiveness of exercise to increase bone mass, or at least arrest the loss of bone mass after menopause, is also in question. Within this framework, section 1 introduces mechanical characteristics of bones to assist the reader in understanding their responses to physical activity. Section 2 reviews hormonal, nutritional and mechanical factors necessary for the growth of bones in length, width and mineral content that produce peak bone mass in the course of childhood and adolescence using a large sample of healthy Caucasian girls and female adolescents for reference. Effectiveness of exercise is evaluated throughout using absolute changes in bone with the underlying assumption that useful exercise should produce changes that approximate or exceed the absolute magnitude of bone parameters in a healthy reference population. Physical activity increases growth in width and mineral content of bones in girls and adolescent females, particularly when it is initiated before puberty, carried out in volumes and at intensities seen in athletes, and accompanied by adequate caloric and calcium intakes. Similar increases are seen in young women following the termination of statural growth in response to athletic training, but not to more limited levels of physical activity characteristic of longitudinal training studies. After 9-12 months of regular exercise, young adult women often show very small benefits to bone health, possibly because of large subject attrition rates, inadequate exercise intensity, duration or frequency, or because at this stage of life accumulation of bone mass may be at its natural peak. The important influence of hormones as well as dietary and specific nutrient abundance on bone growth and health are emphasised, and premature bone loss associated with dietary restriction and estradiol withdrawal in exercise-induced amenorrhoea is described. In section 3, the same assessment is applied to the effects of physical activity in postmenopausal women. Studies of postmenopausal women are presented from the perspective of limitations of the capacity of the skeleton to adapt to mechanical stress of exercise due to altered hormonal status and inadequate intake of specific nutrients. After menopause, effectiveness of exercise to increase bone mineral depends heavily on adequate availability of dietary calcium. Relatively infrequent evidence that physical activity prevents bone loss or increases bone mineral after menopause may be a consequence of inadequate calcium availability or low intensity of exercise in training studies. Several studies with postmenopausal women show modest increases in bone mineral toward the norm seen in a healthy population in response to high-intensity training. Physical activities continue to stimulate increases in bone diameter throughout the lifespan. These exercise-stimulated increases in bone diameter diminish the risk of fractures by mechanically counteracting the thinning of bones and increases in bone porosity. Seven principles of bone adaptation to mechanical stress are reviewed in section 4 to suggest how exercise by human subjects could be made more effective. They posit that exercise should: (i) be dynamic, not static; (ii) exceed a threshold intensity; (iii) exceed a threshold strain frequency; (iv) be relatively brief but intermittent; (v) impose an unusual loading pattern on the bones; (vi) be supported by unlimited nutrient energy; and (vii) include adequate calcium and cholecalciferol (vitamin D3) availability.
Effects of age and recovery duration on peak power output during repeated cycling sprints.
Ratel, S; Bedu, M; Hennegrave, A; Doré, E; Duché, P
2002-08-01
The aim of the present study was to investigate the effects of age and recovery duration on the time course of cycling peak power and blood lactate concentration ([La]) during repeated bouts of short-term high-intensity exercise. Eleven prepubescent boys (9.6 +/- 0.7 yr), nine pubescent boys (15.0 +/- 0.7 yr) and ten men (20.4 +/- 0.8 yr) performed ten consecutive 10 s cycling sprints separated by either 30 s (R30), 1 min (R1), or 5 min (R5) passive recovery intervals against a friction load corresponding to 50 % of their optimal force (50 % Ffopt). Peak power produced at 50 % Ffopt (PP50) was calculated at each sprint including the flywheel inertia of the bicycle. Arterialized capillary blood samples were collected at rest and during the sprint exercises to measure the time course of [La]. In the prepubescent boys, whatever recovery intervals, PP50 remained unchanged during the ten 10 s sprint exercises. In the pubescent boys, PP50 decreased significantly by 18.5 % (p < 0.001) with R30 and by 15.3 % (p < 0.01) with R1 from the first to the tenth sprint but remained unchanged with R5. In the men, PP50 decreased respectively by 28.5 % (p < 0.001) and 11.3 % (p < 0.01) with R30 and R1 and slightly diminished with R5. For each recovery interval, the increase in blood [La] over the ten sprints was significantly lower in the prepubescent boys compared with the pubescent boys and the men. To conclude, the prepubescent boys sustained their PP50 during the ten 10 s sprint exercises with only 30 s recovery intervals. In contrast, the pubescent boys and the men needed 5 min recovery intervals. It was suggested that the faster recovery of PP50 in the prepubescent boys was due to their lower muscle glycolytic activity and their higher muscle oxidative capacity allowing a faster resynthesis in phosphocreatine.
Lazarinis, Nikolaos; Jørgensen, Leif; Ekström, Tommy; Bjermer, Leif; Dahlén, Barbro; Pullerits, Teet; Hedlin, Gunilla; Carlsen, Kai-Håkon; Larsson, Kjell
2014-01-01
Background In mild asthma exercise-induced bronchoconstriction (EIB) is usually treated with inhaled short-acting β2 agonists (SABAs) on demand. Objective The hypothesis was that a combination of budesonide and formoterol on demand diminishes EIB equally to regular inhalation of budesonide and is more effective than terbutaline inhaled on demand. Methods Sixty-six patients with asthma (>12 years of age) with verified EIB were randomised to terbutaline (0.5 mg) on demand, regular budesonide (400 μg) and terbutaline (0.5 mg) on demand, or a combination of budesonide (200 μg) + formoterol (6 μg) on demand in a 6-week, double-blind, parallel-group study (ClinicalTrials.gov identifier: NCT00989833). The patients were instructed to perform three to four working sessions per week. The main outcome was EIB 24 h after the last dosing of study medication. Results After 6 weeks of treatment with regular budesonide or budesonide+formoterol on demand the maximum post-exercise forced expiratory volume in 1 s fall, 24 h after the last medication, was 6.6% (mean; 95% CI −10.3 to −3.0) and 5.4% (−8.9 to −1.8) smaller, respectively. This effect was superior to inhalation of terbutaline on demand (+1.5%; −2.1 to +5.1). The total budesonide dose was approximately 2.5 times lower in the budesonide+formoterol group than in the regular budesonide group. The need for extra medication was similar in the three groups. Conclusions The combination of budesonide and formoterol on demand improves asthma control by reducing EIB in the same order of magnitude as regular budesonide treatment despite a substantially lower total steroid dose. Both these treatments were superior to terbutaline on demand, which did not alter the bronchial response to exercise. The results question the recommendation of prescribing SABAs as the only treatment for EIB in mild asthma. PMID:24092567
Triiodothyronine, beta-adrenergic receptors, agonist responses, and exercise capacity.
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.
Exercise detraining: Applicability to microgravity
NASA Technical Reports Server (NTRS)
Coyle, Edward F.
1994-01-01
Physical training exposes the various systems of the body to potent physiologic stimuli. These stimuli induce specific adaptations that enhance an individual's tolerance for the type of exercise encountered in training. The level of adaptation and the magnitude of improvement in exercise tolerance is proportional to the potency of the physical training stimuli. Likewise, our bodies are stimulated by gravity, which promotes adaptations of both the cardiovascular and skeletal muscles. Exposure to microgravity removes normal stimuli to these systems, and the body adapts to these reduced demands. In many respects the cessation of physical training in athletes and the transition from normal gravity to microgravity represent similar paradigms. Inherent to these situations is the concept of the reversibility of the adaptations induced by training or by exposure to normal gravity. The reversibility concept holds that when physical training is stopped (i.e., detraining) or reduced, or a person goes from normal gravity to microgravity, the bodily systems readjust in accordance with the diminished physiologic stimuli. The focus of this chapter is on the time course of loss of the adaptations to endurance training as well as on the possibility that certain adaptations persist, to some extent, when training is stopped. Because endurance exercise training generally improves cardiovascular function and promotes metabolic adaptations within the exercising skeletal musculature, the reversibility of these specific adaptations is considered. These observations have some applicability to the transition from normal to microgravity.
Reduced Cardiac Vagal Modulation Impacts on Cognitive Performance in Chronic Fatigue Syndrome
Beaumont, Alison; Burton, Alexander R.; Lemon, Jim; Bennett, Barbara K.; Lloyd, Andrew; Vollmer-Conna, Uté
2012-01-01
Background Cognitive difficulties and autonomic dysfunction have been reported separately in patients with chronic fatigue syndrome (CFS). A role for heart rate variability (HRV) in cognitive flexibility has been demonstrated in healthy individuals, but this relationship has not as yet been examined in CFS. The objective of this study was to examine the relationship between HRV and cognitive performance in patients with CFS. Methods Participants were 30 patients with CFS and 40 healthy controls; the groups were matched for age, sex, education, body mass index, and hours of moderate exercise/week. Questionnaires were used to obtain relevant medical and demographic information, and assess current symptoms and functional impairment. Electrocardiograms, perceived fatigue/effort and performance data were recorded during cognitive tasks. Between–group differences in autonomic reactivity and associations with cognitive performance were analysed. Results Patients with CFS showed no deficits in performance accuracy, but were significantly slower than healthy controls. CFS was further characterized by low and unresponsive HRV; greater heart rate (HR) reactivity and prolonged HR-recovery after cognitive challenge. Fatigue levels, perceived effort and distress did not affect cognitive performance. HRV was consistently associated with performance indices and significantly predicted variance in cognitive outcomes. Conclusions These findings reveal for the first time an association between reduced cardiac vagal tone and cognitive impairment in CFS and confirm previous reports of diminished vagal activity. PMID:23166694
1993-01-01
NE- induced aMT secretion into 1111 their pineals in vitro, either to the transmitter the medium was markedly diminished in pineals taken S...al., 1988; Bieck et al., 1988; Khoory and effect of exercise ) but without assessing whether the Stemme, 1988; Tortosa et al., 1989; Soudtre et al...above twice aMT surge) or injected ISO ( inducing a secondary the conservative estimate of the ALD. surge at night after acute inhibition by light) re
Heat Production During Countermeasure Exercises Planned for the International Space Station
NASA Technical Reports Server (NTRS)
Rapley, Michael G.; Lee, Stuart M. C.; Guilliams, Mark E.; Greenisen, Michael C.; Schneider, Suzanne M.
2004-01-01
This investigation's purpose was to determine the amount of heat produced when performing aerobic and resistance exercises planned as part of the exercise countermeasures prescription for the ISS. These data will be used to determine thermal control requirements of the Node 1 and other modules where exercise hardware might reside. To determine heat production during resistive exercise, 6 subjects using the iRED performed 5 resistance exercises which form the core exercises of the current ISS resistive exercise countermeasures. Each exerciser performed a warm-up set at 50% effort, then 3 sets of increasing resistance. We measured oxygen consumption and work during each exercise. Heat loss was calculated as the difference between the gross energy expenditure (minus resting metabolism) and the work performed. To determine heat production during aerobic exercise, 14 subjects performed an interval, cycle exercise protocol and 7 subjects performed a continuous, treadmill protocol. Each 30-min. exercise is similar to exercises planned for ISS. Oxygen consumption monitored continuously during the exercises was used to calculate the gross energy expenditure. For cycle exercise, work performed was calculated based on the ergometer's resistance setting and pedaling frequency. For treadmill, total work was estimated by assuming 25% work efficiency and subtracting the calculated heat production and resting metabolic rate from the gross energy expenditure. This heat production needs to be considered when determining the location of exercise hardware on ISS and designing environmental control systems. These values reflect only the human subject s produced heat; heat produced by the exercise hardware also will contribute to the heat load.
Langfort, J; Zarzeczny, R; Pilis, W; Nazar, K; Kaciuba-Uścitko, H
1997-01-01
The aim of this study was to find out whether a low-carbohydrate diet (L-CHO) affects: (1) the capacity for all-out anaerobic exercise, and (2) hormonal and metabolic responses to this type of exercise. To this purpose, eight healthy subjects underwent a 30-s bicycle Wingate test preceded by either 3 days of a controlled mixed diet (130 kJ/kg of body mass daily, 50% carbohydrate, 30% fat, 20% protein) or 3 days of an isoenergetic L-CHO diet (up to 5% carbohydrate, 50% fat, 45% protein) in a randomized order. Before and during 1 h after the exercise venous blood samples were taken for measurement of blood lactate (LA), beta-hydroxybutyrate (beta-HB), glucose, adrenaline (A), noradrenaline (NA) and insulin levels. Oxygen consumption (VO2) was also determined. It was found that the L-CHO diet diminished the mean power output during the 30-s exercise bout [533 (7) W vs 581 (7) W, P < 0.05] without changing the maximal power attained during the first or second 5-s interval of the exercise. In comparison with the data obtained after the consumption of a mixed diet, after the consumption of a L-CHO diet resting plasma concentrations of beta-HB [2.38 (0.18) vs 0.23 (0.01) mmol x l(-1), P < 0.001] and NA [4.81 (0.68) vs 2.2 (0.31) nmol x l(-1), P < 0.05] were higher, while glucose [4.6 (0.1) vs 5.7 (0.2) mmol x l(-1), P < 0.05] and insulin concentrations [11.9 (0.9) vs 21.8 (1.8) mU x l(-1)] were lower. The 1-h post-exercise excess of VO2 [9.1 (0.25) vs 10.6 (0.25) 1, P < 0.05], and blood LA measured 3 min after the exercise [9.5 (0.4) vs 10.6 (0.5) mmol x l(-1), P < 0.05] were lower following the L-CHO treatment, whilst plasma NA and A concentrations reached higher values [2.24 (0.40) vs 1.21 (0.13) nmol x l(-1) and 14.30 (1.41) vs 8.20 (1.31) nmol x l(-1), P < 0.01, respectively]. In subjects on the L-CHO diet, the plasma beta-HB concentration decreased quickly after exercise, attaining approximately 30% of the pre-exercise value within 60 min, while insulin and glucose levels were elevated. The main conclusions of this study are: (1) a L-CHO diet is detrimental to anaerobic work capacity, possibly because of a reduced muscle glycogen store and decreased rate of glycolysis; (2) reduced carbohydrate intake for 3 days enhances activity of the sympathoadrenal system at rest and after exercise.
NASA Astrophysics Data System (ADS)
Ruslan, Siti Zaharah Mohd; Jaffar, Maheran Mohd
2017-05-01
Islamic banking in Malaysia offers variety of products based on Islamic principles. One of the concepts is a diminishing musyarakah. The concept of diminishing musyarakah helps Muslims to avoid transaction which are based on riba. The diminishing musyarakah can be defined as an agreement between capital provider and entrepreneurs that enable entrepreneurs to buy equity in instalments where profits and losses are shared based on agreed ratio. The objective of this paper is to determine the internal rate of return (IRR) for a diminishing musyarakah model by applying a numerical method. There are several numerical methods in calculating the IRR such as by using an interpolation method and a trial and error method by using Microsoft Office Excel. In this paper we use a bisection method and secant method as an alternative way in calculating the IRR. It was found that the diminishing musyarakah model can be adapted in managing the performance of joint venture investments. Therefore, this paper will encourage more companies to use the concept of joint venture in managing their investments performance.
Medical psychology in exercise and sport.
Dishman, R K
1985-01-01
Several psychological outcomes that accompany acute and chronic exercise have medical significance. Transient reductions in somatic tension and subjective anxiety appear most reliable. Symptom abatement in moderate depression can occur with chronic exercise in a manner comparable to psychotherapy and may offer a better prognosis in some instances. Other cognitive, behavioral, and perceptual events associated with exercise may assist in managing mental health, and exercise has been successfully used as a therapeutic adjunct in a variety of psychiatric disorders. Regular exercise may also complement treatments designed to manage aspects of coronary-prone behavior and psychoendocrine responsivity to mental stress. The lack of strict experimental control or effective placebo contrasts in most exercise studies precludes a convincing argument that exercise causes the psychological outcomes observed. Rather, expectancy of benefits, generalized treatment or attention effects, social reinforcement, and past history or selection bias represent likely alternatives. These competing explanations do not discount, however, that many individuals benefit in a clinically significant way. Exercise offers a low-cost alternative or adjunct with side effects that appear largely health-related. Although the effective psychological dosage or modality has not been quantified, current physiologic guidelines of the American College of Sports Medicine (large muscle rhythmic activity, for 20 to 60 minutes, 3 to 5 days per week at 60 to 80 per cent age-adjusted maximal heart rate), or a weekly caloric cost of 2000 kcal, should be effective with little medical risk. However, no evidence confirms that an increase in metabolic or psychoendocrine tolerance to exercise is necessary or sufficient for psychological outcomes to occur. Although biologic adaptations are known to follow exercise training and subside with diminished activity, there is currently no objective evidence that habitual exercise leads to dependence. If exercise has use in managing subjective or somatic symptoms, these may return during periods of exercise abstinence. Moreover, despite popular hypotheses concerning endorphins and biogenic amines, no direct relationships have yet been shown between exercise-induced mood swings and peripheral biochemical events. A proportion of habitual runners have reported acute episodes of euphoria-like states during or following exercise, but this remains a subjective and unpredictable event that may be related to psychophysiologic relaxation or acute changes in self-esteem.(ABSTRACT TRUNCATED AT 400 WORDS)
Matsubayashi, Yoshito; Asakawa, Yasuyoshi; Yamaguchi, Haruyasu
2016-01-01
[Purpose] This study examined whether low-frequency group exercise improved the motor functions of community-dwelling elderly people in a rural area when combined with home exercise with self-monitoring. [Subjects] The subjects were community-dwelling elderly people in a rural area of Japan. [Methods] One group (n = 50) performed group exercise combined with home exercise with self-monitoring. Another group (n = 37) performed group exercise only. Low-frequency group exercise (warm-up, exercises for motor functions, and cool-down) was performed in seven 40 to 70-minute sessions over 9 weeks by both groups. Five items of motor functions were assessed before and after the intervention. [Results] Significant interactions were observed between groups and assessment times for all motor functions. Improvements in motor functions were significantly greater in the group that performed group exercise combined with home exercise with self-monitoring than in the group that performed group exercise only. Post-hoc comparisons revealed significant differences in 3 items of motor functions. No significant improvements were observed in motor functions in the group that performed group exercise only. [Conclusions] Group exercise combined with home exercise with self-monitoring improved motor functions in the setting of low-frequency group exercise for community-dwelling elderly people in a rural area. PMID:27065520
Role of pulmonary diseases and physical condition in the regulation of vasoactive hormones.
Hietanen, E; Marniemi, J; Liippo, K; Seppänen, A; Hartiala, J; Viinamäki, O
1988-12-01
Lungs have many non-respiratory metabolic functions, of which some take place in the capillary endothelium, while others are in parenchymal lung tissue. We have studied the role of the lungs in the metabolism of vasoactive and some other hormones by comparing patients who have undergone lung resection to those having various obstructive or fibrotic lung diseases. We have also compared these groups with persons in good physical health. The data suggested that lung resection patients had low angiotensin II levels in plasma but the response of angiotensin II to exercise was normal. Also adrenalin concentration was low in the lung resection group while dopamine did not show any significant difference between the groups. When hormone levels were correlated to the exercise data, renin levels were especially related to physical condition. Serum post-exercise renin values were inversely related to the uneven distribution of lung perfusion, possibly thus reflecting the diminished pulmonary vascularization. A negative association was found between angiotensin II and diffusion capacity. Thus, the angiotensin II levels may preferably be controlled by the non-circulatory functions of the lungs.
Kwon, Insu; Jang, Yongchul; Cho, Joon-Yong; Jang, Young C; Lee, Youngil
2018-05-01
Elevation of anabolism and concurrent suppression of catabolism are critical metabolic adaptations for muscular hypertrophy in response to resistance exercise (RE). Here, we investigated if RE-induced muscular hypertrophy is acquired by modulating a critical catabolic process autophagy. Male Wistar Hannover rats (14 weeks old) were randomly assigned to either sedentary control (SC, n = 10) or resistance exercise (RE, n = 10). RE elicited significant hypertrophy of flexor digitorum profundus (FDP) muscles in parallel with enhancement in anabolic signaling pathways (phosphorylation of AKT, mTOR, and p70S6K). Importantly, RE-treated FDP muscle exhibited a significant decline in autophagy evidenced by diminished phosphorylation levels of AMPK, a decrease in LC3-II/LC3-I ratio, an increase in p62 level, and a decline in active form of lysosomal protease CATHEPSIN L in the absence of alterations of key autophagy proteins: ULK1 phosphorylation, BECLIN1, and BNIP3. Our study suggests that RE-induced hypertrophy is achieved by potentiating anabolism and restricting autophagy-induced catabolism.
Feng, Jingjie; Zhou, Congcong; He, Cheng; Li, Yuan; Ye, Xuesong
2017-04-01
In this paper, a miniaturized wearable core body temperature (CBT) monitoring system based on the dual heat flux (DHF) principle was developed. By interspersing calcium carbonate powder in PolyDimethylsiloxane (PDMS), a reformative heat transfer medium was produced to reduce the thermal equilibrium time. Besides, a least mean square (LMS) algorithm based active noise cancellation (ANC) method was adopted to diminish the impact of ambient temperature fluctuations. Theoretical analyses, finite element simulation, experiments on a hot plate and human volunteers were performed. The results showed that the proposed system had the advantages of small size, reduced initial time (~23.5 min), and good immunity to fluctuations of the air temperature. For the range of 37-41 °C on the hot plate, the error compared with a Fluke high accuracy thermometer was 0.08 ± 0.20 °C. In the human experiments, the measured temperature in the rest trial (34 subjects) had a difference of 0.13 ± 0.22 °C compared with sublingual temperature, while a significant increase of 1.36 ± 0.44 °C from rest to jogging was found in the exercise trial (30 subjects). This system has the potential for reliable continuous CBT measurement in rest and can reflect CBT variations during exercise.
Use of Factor Mixture Modeling to Capture Spearman's Law of Diminishing Returns
ERIC Educational Resources Information Center
Reynolds, Matthew R.; Keith, Timothy Z.; Beretvas, S. Natasha
2010-01-01
Spearman's law of diminishing returns (SLODR) posits that at higher levels of general cognitive ability the general factor ("g") performs less well in explaining individual differences in cognitive test performance. Research has generally supported SLODR, but previous research has required the a priori division of respondents into…
Lifestyle change diminishes a hypertensive response to exercise in type 2 diabetes.
Schultz, Martin G; Hordern, Matthew D; Leano, Rodel; Coombes, Jeffrey S; Marwick, Thomas H; Sharman, James E
2011-05-01
A hypertensive response to exercise (HRE) is common in patients with type 2 diabetes and is associated with increased left ventricular (LV) mass and mortality. This study aimed to determine whether lifestyle modification would improve exercise blood pressure (BP) and reduce LV mass in patients with type 2 diabetes. One hundred and eighty-five patients with type 2 diabetes were randomized to 1 yr of lifestyle intervention (n=97, mean ± SD age=54.7 ± 11.3 yr, 51% men) or usual care (control; n=88, age=53.8 ± 8.1 yr, 61% men). Brachial BP was measured at rest and during a graded maximal exercise test at baseline and 1 yr. Patients also underwent two-dimensional echocardiography to determine LV dimensions. A subgroup of 61 patients had resting and exercise central BP estimated from radial tonometry. An HRE was defined as a maximal exercise systolic BP of ≥210 mm Hg for men and ≥190 mm Hg for women. At study entry, there were 101 patients (55%) with an HRE (n=51 controls). Compared with controls, lifestyle intervention significantly reduced the propensity to develop an HRE in those participants who did not have HRE at baseline (29.8% vs 59.5%, P=0.006). However, absolute values of exercise and resting (brachial and central) BP and LV mass were not significantly changed (all P values >0.05). There were significant (all P values <0.05) improvements in V˙O2max, body mass index, plasma glucose, insulin resistance, and HDL cholesterol after lifestyle intervention compared with control. Lifestyle intervention significantly attenuates the development of an HRE but does not reduce cardiac size after 1 yr in patients with type 2 diabetes. © 2011 by the American College of Sports Medicine
Stöhr, Eric J; González-Alonso, José; Pearson, James; Low, David A; Ali, Leena; Barker, Horace; Shave, Rob
2011-09-01
The purpose of this study was to determine whether the reduction in stroke volume (SV), previously shown to occur with dehydration and increases in internal body temperatures during prolonged exercise, is caused by a reduction in left ventricular (LV) function, as indicated by LV volumes, strain, and twist ("LV mechanics"). Eight healthy men [age: 20 ± 2, maximal oxygen uptake (VO₂max): 58 ± 7 ml·kg⁻¹·min⁻¹] completed two, 1-h bouts of cycling in the heat (35°C, 50% peak power) without fluid replacement, resulting in 2% and 3.5% dehydration, respectively. Conventional and two-dimensional speckle-tracking echocardiography was used to determine LV volumes, strain, and twist at rest and during one-legged knee-extensor exercise at baseline, both levels of dehydration, and following rehydration. Progressive dehydration caused a significant reduction in end-diastolic volume (EDV) and SV at rest and during one-legged knee-extensor exercise (rest: Δ-33 ± 14 and Δ-21 ± 14 ml, respectively; exercise: Δ-30 ± 10 and Δ-22 ± 9 ml, respectively, during 3.5% dehydration). In contrast to the marked decline in EDV and SV, systolic and diastolic LV mechanics were either maintained or even enhanced with dehydration at rest and during knee-extensor exercise. We conclude that dehydration-induced reductions in SV at rest and during exercise are the result of reduced LV filling, as reflected by the decline in EDV. The concomitant maintenance of LV mechanics suggests that the decrease in LV filling, and consequently ejection, is likely caused by the reduction in blood volume and/or diminished filling time rather than impaired LV function.
Ober, John; Gillette, Robert L; Angle, Thomas Craig; Haney, Pamela; Fletcher, Daniel J; Wakshlag, Joseph J
2016-01-01
Optimal dietary protocols for the athletic canine are often defined by requirements for endurance athletes that do not always translate into optimal dietary interventions for all canine athletes. Prior research studying detection dogs suggests that dietary fat sources can influence olfaction; however, as fat is added to the diet the protein calories can be diminished potentially resulting in decreased red blood cell counts or albumin status. Optimal macronutrient profile for detection dogs may be different considering the unique work they engage in. To study a calorically low protein: high fat (18:57% ME), high protein: high fat (27:57% ME), and high protein: low fat (27:32% ME) approach to feeding, 17 dogs were provided various diets in a 3 × 3 cross over design. Dogs were exercised on a treadmill and blood was taken pre-exercise, immediately post-exercise, 10- and 20-min post-exercise to assess complete blood count, serum chemistry, blood gases, and cortisol; as well as rectal and core body temperature. Exercise induced a decrease in serum phosphorus, potassium, and increases in non-esterified fatty acids and cortisol typical of moderate exercise bouts. A complete and balanced high protein: high-fat diet (27:57% ME) induced decreases in serum cortisol and alkaline phosphatase. Corn oil top dressed low protein: high-fat diet (18:57% ME) induced a slightly better thermal recovery than a complete and balanced high protein: high fat diet and a high protein: low fat (27%:32% ME) diet suggesting some mild advantages when using the low protein: high fat diet that warrant further investigation regarding optimal protein and fat calories and thermal recovery.
Ober, John; Gillette, Robert L.; Angle, Thomas Craig; Haney, Pamela; Fletcher, Daniel J.; Wakshlag, Joseph J.
2016-01-01
Optimal dietary protocols for the athletic canine are often defined by requirements for endurance athletes that do not always translate into optimal dietary interventions for all canine athletes. Prior research studying detection dogs suggests that dietary fat sources can influence olfaction; however, as fat is added to the diet the protein calories can be diminished potentially resulting in decreased red blood cell counts or albumin status. Optimal macronutrient profile for detection dogs may be different considering the unique work they engage in. To study a calorically low protein: high fat (18:57% ME), high protein: high fat (27:57% ME), and high protein: low fat (27:32% ME) approach to feeding, 17 dogs were provided various diets in a 3 × 3 cross over design. Dogs were exercised on a treadmill and blood was taken pre-exercise, immediately post-exercise, 10- and 20-min post-exercise to assess complete blood count, serum chemistry, blood gases, and cortisol; as well as rectal and core body temperature. Exercise induced a decrease in serum phosphorus, potassium, and increases in non-esterified fatty acids and cortisol typical of moderate exercise bouts. A complete and balanced high protein: high-fat diet (27:57% ME) induced decreases in serum cortisol and alkaline phosphatase. Corn oil top dressed low protein: high-fat diet (18:57% ME) induced a slightly better thermal recovery than a complete and balanced high protein: high fat diet and a high protein: low fat (27%:32% ME) diet suggesting some mild advantages when using the low protein: high fat diet that warrant further investigation regarding optimal protein and fat calories and thermal recovery. PMID:27532039
van Koulil, S; van Lankveld, W; Kraaimaat, F W; van Helmond, T; Vedder, A; van Hoorn, H; Donders, A R T; Wirken, L; Cats, H; van Riel, P L C M; Evers, A W M
2011-12-01
Patients with fibromyalgia have diminished levels of physical fitness, which may lead to functional disability and exacerbating complaints. Multidisciplinary treatment comprising cognitive-behavioural therapy (CBT) and exercise training has been shown to be effective in improving physical fitness. However, due to the high drop-out rates and large variability in patients' functioning, it was proposed that a tailored treatment approach might yield more promising treatment outcomes. High-risk fibromyalgia patients were randomly assigned to a waiting list control group (WLC) or a treatment condition (TC), with the treatment consisting of 16 twice-weekly sessions of CBT and exercise training tailored to the patient's cognitive-behavioural pattern. Physical fitness was assessed with two physical tests before and 3 months after treatment and at corresponding intervals in the WLC. Treatment effects were evaluated using linear mixed models. The level of physical fitness had improved significantly in the TC compared with the WLC. Attrition rates were low, effect sizes large and reliable change indices indicated a clinically relevant improvement among the TC. A tailored multidisciplinary treatment approach for fibromyalgia consisting of CBT and exercise training is well tolerated, yields clinically relevant changes, and appears a promising approach to improve patients' physical fitness. ClinicalTrials.gov ID NCT00268606.
The effect of physical activity on sleep quality, well-being, and affect in academic stress periods.
Wunsch, Kathrin; Kasten, Nadine; Fuchs, Reinhard
2017-01-01
The stress-buffering hypothesis postulates that physical activity and exercise can buffer the negative effects of (academic) stress on health. It still remains an open question whether students, who regularly engage in physical activity and exercise within their academic examination period, can successfully diminish these negative effects. Sixty-four subjects participated in this study and completed a total of five surveys, with T1 at the end of the semester break (baseline) and T2-T5 being presented every Friday in the last 4 weeks of the semester (examination period). They were asked to answer questions about their activity level, sleep quality, well-being and affect. Hierarchical linear models showed significant dependencies on time for all dependent measures. The expansion of the model for exercise also showed significant main effects of this predictor on well-being and positive affect (PA) and negative affect. Moreover, significant interactions with time for sleep quality and PA were found. Results suggest that physical activity and exercise in the academic examination period may be able to buffer the negative effects of stress on health-related outcomes. Therefore, activity levels should be maintained in times of high stress to prevent negative effects on sleep, well-being and affect in students.
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).
Price, T B; Perseghin, G; Duleba, A; Chen, W; Chase, J; Rothman, D L; Shulman, R G; Shulman, G I
1996-01-01
To examine the impact of insulin resistance on the insulin-dependent and insulin-independent portions of muscle glycogen synthesis during recovery from exercise, we studied eight young, lean, normoglycemic insulin-resistant (IR) offspring of individuals with non-insulin-dependent diabetes mellitus and eight age-weight matched control (CON) subjects after plantar flexion exercise that lowered muscle glycogen to approximately 25% of resting concentration. After approximately 20 min of exercise, intramuscular glucose 6-phosphate and glycogen were simultaneously monitored with 31P and 13C NMR spectroscopies. The postexercise rate of glycogen resynthesis was nonlinear. Glycogen synthesis rates during the initial insulin independent portion (0-1 hr of recovery) were similar in the two groups (IR, 15.5 +/- 1.3 mM/hr and CON, 15.8 +/- 1.7 mM/hr); however, over the next 4 hr, insulin-dependent glycogen synthesis was significantly reduced in the IR group [IR, 0.1 +/- 0.5 mM/hr and CON, 2.9 +/- 0.2 mM/hr; (P < or = 0.001)]. After exercise there was an initial rise in glucose 6-phosphate concentrations that returned to baseline after the first hour of recovery in both groups. In summary, we found that following muscle glycogen-depleting exercise, IR offspring of parents with non-insulin-dependent diabetes mellitus had (i) normal rates of muscle glycogen synthesis during the insulin-independent phase of recovery from exercise and (ii) severely diminished rates of muscle glycogen synthesis during the subsequent recovery period (2-5 hr), which has previously been shown to be insulin-dependent in normal CON subjects. These data provide evidence that exercise and insulin stimulate muscle glycogen synthesis in humans by different mechanisms and that in the IR subjects the early response to stimulation by exercise is normal. PMID:8643574
26 CFR 1.246-5 - Reduction of holding periods in certain situations.
Code of Federal Regulations, 2011 CFR
2011-04-01
... in which a taxpayer has diminished its risk of loss by holding one or more other positions with... property primarily reflect the performance of— (A) A single firm or enterprise; (B) The same industry or... property. (2) Diminished risk of loss. A taxpayer has diminished its risk of loss on its stock by holding...
Performance and mood-state parameters during 30-day 6 deg head-down bed rest with exercise training
NASA Technical Reports Server (NTRS)
Deroshia, Charles W.; Greenleaf, J. E.
1993-01-01
A study aimed at determining if the performance and mood impairments occur in bed-rested subjects, and if different exercise-training regimens modify or prevent them is presented. Eighteen healthy men were divided into three groups performing no exercise, isotonic exercise, and isokinetic exercise. Few deleterious changes occurred in performance and mood of the three groups which did not exceed baseline ambulatory levels. It is concluded that mood and performance did not deteriorate in response to prolonged bedrest and were not altered by exercise training.
Exer-Genie(Registered Trademark) Exercise Device Hardware Evaluation
NASA Technical Reports Server (NTRS)
Schaffner, Grant; Sharp,Carwyn; Stroud, Leah
2008-01-01
An engineering evaluation was performed on the ExerGenie(r) exercise device to quantify its capabilities and limitations to address questions from the Constellation Program. Three subjects performed rowing and circuit training sessions to assess the suitability of the device for aerobic exercise. Three subjects performed a resistive exercise session to assess the suitability of the device for resistive exercise. Since 1 subject performed both aerobic and resistive exercise sessions, a total of 5 subjects participated.
Fortington, Lauren V; Donaldson, Alex; Lathlean, Tim; Young, Warren B; Gabbe, Belinda J; Lloyd, David; Finch, Caroline F
2015-05-01
To obtain benefits from sports injury prevention programs, players are instructed to perform the exercises as prescribed. We developed an observational checklist to measure the quality of exercise performance by players participating in FootyFirst, a coach-led, exercise-based, lower-limb injury prevention program in community Australian Football (AF). Observational. The essential performance criteria for each FootyFirst exercise were described in terms of the technique, volume and intensity required to perform each exercise. An observational checklist was developed to evaluate each criterion through direct visual observation of players at training. The checklist was trialled by two independent raters who observed the same 70 players completing the exercises at eight clubs. Agreement between observers was assessed by Kappa-statistics. Exercise fidelity was defined as the proportion of observed players who performed all aspects of their exercises correctly. The raters agreed on 61/70 observations (87%) (Kappa=0.72, 95% CI: 0.55; 0.89). Of the observations with agreed ratings, 41 (67%) players were judged as performing the exercises as prescribed. The observational checklist demonstrated high inter-rater reliability. Many players observed did not perform the exercises as prescribed, raising concern as to whether they would be receiving anticipated program benefits. Where quality of exercise performance is important, evaluation and reporting of program fidelity should include direct observations of participants. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Maximal exercise and muscle oxygen extraction in acclimatizing lowlanders and high altitude natives
Lundby, Carsten; Sander, Mikael; van Hall, Gerrit; Saltin, Bengt; Calbet, José A L
2006-01-01
The tight relation between arterial oxygen content and maximum oxygen uptake () within a given person at sea level is diminished with altitude acclimatization. An explanation often suggested for this mismatch is impairment of the muscle O2 extraction capacity with chronic hypoxia, and is the focus of the present study. We have studied six lowlanders during maximal exercise at sea level (SL) and with acute (AH) exposure to 4100 m altitude, and again after 2 (W2) and 8 weeks (W8) of altitude sojourn, where also eight high altitude native (Nat) Aymaras were studied. Fractional arterial muscle O2 extraction at maximal exercise was 90.0 ± 1.0% in the Danish lowlanders at sea level, and remained close to this value in all situations. In contrast to this, fractional arterial O2 extraction was 83.2 ± 2.8% in the high altitude natives, and did not change with the induction of normoxia. The capillary oxygen conductance of the lower extremity, a measure of oxygen diffusing capacity, was decreased in the Danish lowlanders after 8 weeks of acclimatization, but was still higher than the value obtained from the high altitude natives. The values were (in ml min−1 mmHg−1) 55.2 ± 3.7 (SL), 48.0 ± 1.7 (W2), 37.8 ± 0.4 (W8) and 27.7 ± 1.5 (Nat). However, when correcting oxygen conductance for the observed reduction in maximal leg blood flow with acclimatization the effect diminished. When calculating a hypothetical leg at altitude using either the leg blood flow or the O2 conductance values obtained at sea level, the former values were almost completely restored to sea level values. This would suggest that the major determinant for not to increase with acclimatization is the observed reduction in maximal leg blood flow and O2 conductance. PMID:16581864
English, Brett A; Appalsamy, Martin; Diedrich, Andre; Ruggiero, Alicia M; Lund, David; Wright, Jane; Keller, Nancy R; Louderback, Katherine M; Robertson, David; Blakely, Randy D
2010-09-01
Healthy cardiovascular function relies on a balanced and responsive integration of noradrenergic and cholinergic innervation of the heart. High-affinity choline uptake by cholinergic terminals is pivotal for efficient ACh production and release. To date, the cardiovascular impact of diminished choline transporter (CHT) expression has not been directly examined, largely due to the transporter's inaccessibility in vivo. Here, we describe findings from cardiovascular experiments using transgenic mice that bear a CHT genetic deficiency. Whereas CHT knockout (CHT(-/-)) mice exhibit early postnatal lethality, CHT heterozygous (CHT(+/-)) mice survive, grow, and reproduce normally and exhibit normal spontaneous behaviors. However, the CHT(+/-) mouse heart displays significantly reduced levels of high-affinity choline uptake accompanied by significantly reduced levels of ACh. Telemeterized recordings of cardiovascular function in these mice revealed tachycardia and hypertension at rest. After treadmill exercise, CHT(+/-) mice exhibited slower heart rate recovery, consistent with a diminished cholinergic reserve, a contention validated through direct vagal nerve stimulation. Echocardiographic and histological experiments revealed an age-dependent decrease in fractional shortening, increased left ventricular dimensions, and increased ventricular fibrosis, consistent with ventricular dysfunction. These cardiovascular phenotypes of CHT(+/-) mice encourage an evaluation of humans bearing reduced CHT expression for their resiliency in maintaining proper heart function as well as risk for cardiovascular disease.
Fiechter, Joshua L; Benjamin, Aaron S
2017-08-28
Retrieval practice has been shown to be a highly effective tool for enhancing memory, a fact that has led to major changes to educational practice and technology. However, when initial learning is poor, initial retrieval practice is unlikely to be successful and long-term benefits of retrieval practice are compromised or nonexistent. Here, we investigate the benefit of a scaffolded retrieval technique called diminishing-cues retrieval practice (Finley, Benjamin, Hays, Bjork, & Kornell, Journal of Memory and Language, 64, 289-298, 2011). Under learning conditions that favored a strong testing effect, diminishing cues and standard retrieval practice both enhanced memory performance relative to restudy. Critically, under learning conditions where standard retrieval practice was not helpful, diminishing cues enhanced memory performance substantially. These experiments demonstrate that diminishing-cues retrieval practice can widen the range of conditions under which testing can benefit memory, and so can serve as a model for the broader application of testing-based techniques for enhancing learning.
14 CFR 25.123 - En route flight paths.
Code of Federal Regulations, 2010 CFR
2010-01-01
... must represent the actual climb performance diminished by a gradient of climb of 1.1 percent for two... degradation of the gradient of climb is greater than one-half of the applicable actual-to-net flight path...-inoperative net flight path data must represent the actual climb performance diminished by a gradient of climb...
Rooney, Sarah Ilkhanipour; Baskin, Rachel; Torino, Daniel J.; Vafa, Rameen P.; Khandekar, Pooja S.; Kuntz, Andrew F.; Soslowsky, Louis J.
2017-01-01
Background Previous studies have shown that ibuprofen is detrimental to tissue healing following acute injury; however, the effects of ibuprofen when combined with non-injurious exercise are debated. Hypothesis We hypothesized that administration of ibuprofen to rats undergoing a non-injurious treadmill exercise protocol would abolish the beneficial adaptations found with exercise but have no effect on sedentary muscle and tendon properties. Study Design Controlled laboratory study Methods Rats were divided into exercise or cage activity (sedentary) groups and acute (a single bout of exercise followed by 24 hours of rest) and chronic (2 or 8 weeks of repeated exercise) time points. Half of the rats received ibuprofen to investigate the effects of this drug over time when combined with different activity levels (exercise and sedentary). Supraspinatus tendons were used for mechanical testing and histology (organization, cell shape, cellularity), and supraspinatus muscles were used for morphological (fiber CSA, centrally nucleated fibers) and fiber type analysis. Results Chronic intake of ibuprofen did not impair supraspinatus tendon organization or mechanical adaptations (stiffness, modulus, max load, max stress, dynamic modulus, or viscoelastic properties) to exercise. Tendon mechanical properties were not diminished and in some instances increased with ibuprofen. In contrast, total supraspinatus muscle fiber cross-sectional area decreased with ibuprofen at chronic time points, and some fiber type-specific changes were detected. Conclusions Chronic administration of ibuprofen does not impair supraspinatus tendon mechanical properties in a rat model of exercise but does decrease supraspinatus muscle fiber cross-sectional area. Clinically, these findings suggest that ibuprofen does not detrimentally affect regulation of supraspinatus tendon adaptions to exercise but does decrease muscle growth. Individuals should be advised on the risk of decreased muscle hypertrophy when consuming ibuprofen. This fundamental study adds to the growing literature on the effects of ibuprofen on musculoskeletal tissues and provides a solid foundation on which future work can build. Clinical Relevance Ibuprofen is a commonly used drug by sedentary individuals and athletes. This study suggests that ibuprofen has tissue-dependent effects that should be considered when prescribing the drug. PMID:27281275
An Acute Bout of Exercise Improves the Cognitive Performance of Older Adults.
Johnson, Liam; Addamo, Patricia K; Selva Raj, Isaac; Borkoles, Erika; Wyckelsma, Victoria; Cyarto, Elizabeth; Polman, Remco C
2016-10-01
There is evidence that an acute bout of exercise confers cognitive benefits, but it is largely unknown what the optimal mode and duration of exercise is and how cognitive performance changes over time after exercise. We compared the cognitive performance of 31 older adults using the Stroop test before, immediately after, and at 30 and 60 min after a 10 and 30 min aerobic or resistance exercise session. Heart rate and feelings of arousal were also measured before, during, and after exercise. We found that, independent of mode or duration of exercise, the participants improved in the Stroop Inhibition task immediately postexercise. We did not find that exercise influenced the performance of the Stroop Color or Stroop Word Interference tasks. Our findings suggest that an acute bout of exercise can improve cognitive performance and, in particular, the more complex executive functioning of older adults.
Stretch-Induced Reductions in Throwing Performance Are Attenuated by Warm-up Before Exercise.
Mascarin, Naryana C; Vancini, Rodrigo L; Lira, Claudio A B; Andrade, Marilia S
2015-05-01
Recent investigations have suggested that static stretching (SS) performed before exercise reduces muscular performance. However, it is yet unknown whether dynamic warm-up exercises performed together with SS may actually minimize the detrimental acute effects of stretching on muscular performance. This study aimed to assess the effects of static shoulder stretching exercises, dynamic warm-up exercises, or both together, on muscular performance evaluated by ball throwing. Twenty-one female handball players (age: 16.2 ± 1.0 years [range: 14-18 years], height: 167.0 ± 10.0 cm [range: 158-179 cm], and body mass: 63.3 ± 7.6 kg [range: 50.4-77.4 kg]) performed SS, dynamic warm-up exercises or both, targeting the muscles of the upper limbs. Thereafter, medicine ball throwing distance and handball ball throwing speed tests were performed. Static stretching performed before the medicine ball throwing test reduced performance when compared with the warm-up exercises (95% confidence interval [CI] = 0.02-0.17, p ≤ 0.05, effect size [ES] = 0.34). When a warm-up exercise routine was added to SS, the detrimental effects of SS were abolished (95% CI = -0.01 to 0.18, p > 0.05, ES = 0.31). The throwing speed was the same over the 3 conditions. In conclusion, warm-up exercises performed together with SS abolished the impairment in medicine ball throwing distance. We recommend that athletes perform warm-up exercises together with SS before activity to avoid detrimental effects on muscle strength.
Physical exercise and cognitive performance in the elderly: current perspectives
Kirk-Sanchez, Neva J; McGough, Ellen L
2014-01-01
In an aging population with increasing incidence of dementia and cognitive impairment, strategies are needed to slow age-related decline and reduce disease-related cognitive impairment in older adults. Physical exercise that targets modifiable risk factors and neuroprotective mechanisms may reduce declines in cognitive performance attributed to the normal aging process and protect against changes related to neurodegenerative diseases such as Alzheimer’s disease and other types of dementia. In this review we summarize the role of exercise in neuroprotection and cognitive performance, and provide information related to implementation of physical exercise programs for older adults. Evidence from both animal and human studies supports the role of physical exercise in modifying metabolic, structural, and functional dimensions of the brain and preserving cognitive performance in older adults. The results of observational studies support a dose-dependent neuroprotective relationship between physical exercise and cognitive performance in older adults. Although some clinical trials of exercise interventions demonstrate positive effects of exercise on cognitive performance, other trials show minimal to no effect. Although further research is needed, physical exercise interventions aimed at improving brain health through neuroprotective mechanisms show promise for preserving cognitive performance. Exercise programs that are structured, individualized, higher intensity, longer duration, and multicomponent show promise for preserving cognitive performance in older adults. PMID:24379659
DOE Office of Scientific and Technical Information (OSTI.GOV)
Applefeld, M.M.; Slawson, R.G.; Spicer, K.M.
1982-04-01
The long-term cardiac effects of anterior-weighted thoracic mantle field radiotherapy were assessed in 25 patients treated for Hodgkin's disease. These patients underwent an evaluation that included a careful history and physical examination, ECG, M-mode echocardiogram, exercise ECG-gated radionuclide ventriculography, and cardiac catheterization. In these 25 patients evaluated 37-144 months (median, 96) after completion of thoracic mantle radiotherapy, eight had constrictive pericarditis; eight had occult constrictive pericarditis; three had an abnormal response to fluid challenge; three had suspected or proven occlusive coronary artery disease; and one each had a cardiomyopathy and diminished functional capacity on exercise testing. Only one patient appearsmore » to be normal after evaluation. The clinical spectrum of delayed-appearing radiation-induced cardiac disease in patients treated by anterior-weighted thoracic mantle fields and our suggestions for its treatment are discussed.« less
Effect of aerobic exercise on physical performance in patients with Alzheimer's disease.
Sobol, Nanna Aue; Hoffmann, Kristine; Frederiksen, Kristian Steen; Vogel, Asmus; Vestergaard, Karsten; Brændgaard, Hans; Gottrup, Hanne; Lolk, Annette; Wermuth, Lene; Jakobsen, Søren; Laugesen, Lars; Gergelyffy, Robert; Høgh, Peter; Bjerregaard, Eva; Siersma, Volkert; Andersen, Birgitte Bo; Johannsen, Peter; Waldemar, Gunhild; Hasselbalch, Steen Gregers; Beyer, Nina
2016-12-01
Knowledge about the feasibility and effects of exercise programs to persons with Alzheimer's disease is lacking. This study investigated the effect of aerobic exercise on physical performance in community-dwelling persons with mild Alzheimer's disease. The single blinded multi-center RCT (ADEX) included 200 patients, median age 71 yrs (50-89). The intervention group received supervised moderate-to-high intensity aerobic exercise 1 hour × 3/week for 16 weeks. Assessments included cardiorespiratory fitness, single-task physical performance, dual-task performance and exercise self-efficacy. Significant between-group differences in change from baseline (mean [95%CI]) favored the intervention group for cardiorespiratory fitness (4.0 [2.3-5.8] ml/kg/min, P <0.0001) and exercise self-efficacy (1.7 [0.5-2.8] points, P =0.004). Furthermore, an exercise attendance of ≥66.6% resulted in significant positive effects on single-task physical performance and dual-task performance. Aerobic exercise has the potential to improve cardiorespiratory fitness, single-task physical performance, dual-task performance and exercise self-efficacy in community-dwelling patients with mild Alzheimer's disease. Copyright © 2016 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
Equine Welfare during Exercise: An Evaluation of Breathing, Breathlessness and Bridles
Mellor, David J.; Beausoleil, Ngaio J.
2017-01-01
Simple Summary Horses have superior athletic capabilities due largely to their exceptional cardiorespiratory responses during exercise. This has particular relevance to horses’ potential to experience breathlessness, especially when their athletic performance is reduced by impaired respiratory function. Breathlessness, incorporating three types of unpleasant experiences, has been noted as of significant animal welfare concern in other mammals. However, the potential for breathlessness to occur in horses as usually ridden wearing bitted bridles has not yet been evaluated in detail. Accordingly, key physiological responses to exercise and the consequences of impaired respiratory function are outlined. Then the physiological control of breathing and the generation of the aversive experiences of breathlessness are explained. Finally, the potential for horses with unimpaired and impaired respiratory function to experience the different types of breathlessness is evaluated. This information provides a basis for considering the circumstances in which breathlessness may have significant negative welfare impacts on horses as currently ridden wearing bitted bridles. Potential beneficial impacts on respiratory function of using bitless bridles are then discussed with emphasis on the underlying mechanisms and their relevance to breathlessness. It is noted that direct comparisons of cardiorespiratory responses to exercise in horses wearing bitless and bitted bridles are not available and it is recommended that such studies be undertaken. Abstract Horses engaged in strenuous exercise display physiological responses that approach the upper functional limits of key organ systems, in particular their cardiorespiratory systems. Maximum athletic performance is therefore vulnerable to factors that diminish these functional capacities, and such impairment might also lead to horses experiencing unpleasant respiratory sensations, i.e., breathlessness. The aim of this review is to use existing literature on equine cardiorespiratory physiology and athletic performance to evaluate the potential for various types of breathlessness to occur in exercising horses. In addition, we investigate the influence of management factors such as rein and bit use and of respiratory pathology on the likelihood and intensity of equine breathlessness occurring during exercise. In ridden horses, rein use that reduces the jowl angle, sometimes markedly, and conditions that partially obstruct the nasopharynx and/or larynx, impair airflow in the upper respiratory tract and lead to increased flow resistance. The associated upper airway pressure changes, transmitted to the lower airways, may have pathophysiological sequelae in the alveolae, which, in their turn, may increase airflow resistance in the lower airways and impede respiratory gas exchange. Other sequelae include decreases in respiratory minute volume and worsening of the hypoxaemia, hypercapnia and acidaemia commonly observed in healthy horses during strenuous exercise. These and other factors are implicated in the potential for ridden horses to experience three forms of breathlessness—”unpleasant respiratory effort”, “air hunger” and “chest tightness”—which arise when there is a mismatch between a heightened ventilatory drive and the adequacy of the respiratory response. It is not known to what extent, if at all, such mismatches would occur in strenuously exercising horses unhampered by low jowl angles or by pathophysiological changes at any level of the respiratory tract. However, different combinations of the three types of breathlessness seem much more likely to occur when pathophysiological conditions significantly reduce maximal athletic performance. Finally, most horses exhibit clear behavioural evidence of aversion to a bit in their mouths, varying from the bit being a mild irritant to very painful. This in itself is a significant animal welfare issue that should be addressed. A further major point is the potential for bits to disrupt the maintenance of negative pressure in the oropharynx, which apparently acts to prevent the soft palate from rising and obstructing the nasopharynx. The untoward respiratory outcomes and poor athletic performance due to this and other obstructions are well established, and suggest the potential for affected animals to experience significant intensities of breathlessness. Bitless bridle use may reduce or eliminate such effects. However, direct comparisons of the cardiorespiratory dynamics and the extent of any respiratory pathophysiology in horses wearing bitted and bitless bridles have not been conducted. Such studies would be helpful in confirming, or otherwise, the claimed potential benefits of bitless bridle use. PMID:28587125
NASA Astrophysics Data System (ADS)
Peng, Yu-Hao; Heintz, Ryan; Wang, Zhuo; Guo, Yumei; Myers, Kalisa; Scremin, Oscar; Maarek, Jean-Michel; Holschneider, Daniel
2014-12-01
Current rodent connectome projects are revealing brain structural connectivity with unprecedented resolution and completeness. How subregional structural connectivity relates to subregional functional interactions is an emerging research topic. We describe a method for standardized, mesoscopic-level data sampling from autoradiographic coronal sections of the rat brain, and for correlation-based analysis and intuitive display of cortico-cortical functional connectivity (FC) on a flattened cortical map. A graphic user interface “Cx-2D” allows for the display of significant correlations of individual regions-of-interest, as well as graph theoretical metrics across the cortex. Cx-2D was tested on an autoradiographic data set of cerebral blood flow (CBF) of rats that had undergone bilateral striatal lesions, followed by 4 weeks of aerobic exercise training or no exercise. Effects of lesioning and exercise on cortico-cortical FC were examined during a locomotor challenge in this rat model of Parkinsonism. Subregional FC analysis revealed a rich functional reorganization of the brain in response to lesioning and exercise that was not apparent in a standard analysis focused on CBF of isolated brain regions. Lesioned rats showed diminished degree centrality of lateral primary motor cortex, as well as neighboring somatosensory cortex--changes that were substantially reversed in lesioned rats following exercise training. Seed analysis revealed that exercise increased positive correlations in motor and somatosensory cortex, with little effect in non-sensorimotor regions such as visual, auditory, and piriform cortex. The current analysis revealed that exercise partially reinstated sensorimotor FC lost following dopaminergic deafferentation. Cx-2D allows for standardized data sampling from images of brain slices, as well as analysis and display of cortico-cortical FC in the rat cerebral cortex with potential applications in a variety of autoradiographic and histologic studies.
The effect of lifelong exercise dose on cardiovascular function during exercise
Carrick-Ranson, Graeme; Hastings, Jeffrey L.; Bhella, Paul S.; Fujimoto, Naoki; Shibata, Shigeki; Palmer, M. Dean; Boyd, Kara; Livingston, Sheryl; Dijk, Erika
2014-01-01
An increased “dose” of endurance exercise training is associated with a greater maximal oxygen uptake (V̇o2max), a larger left ventricular (LV) mass, and improved heart rate and blood pressure control. However, the effect of lifelong exercise dose on metabolic and hemodynamic response during exercise has not been previously examined. We performed a cross-sectional study on 101 (69 men) seniors (60 yr and older) focusing on lifelong exercise frequency as an index of exercise dose. These included 27 who had performed ≤2 exercise sessions/wk (sedentary), 25 who performed 2–3 sessions/wk (casual), 24 who performed 4–5 sessions/wk (committed) and 25 who performed ≥6 sessions/wk plus regular competitions (Masters athletes) over at least the last 25 yr. Oxygen uptake and hemodynamics [cardiac output, stroke volume (SV)] were collected at rest, two levels of steady-state submaximal exercise, and maximal exercise. Doppler ultrasound measures of LV diastolic filling were assessed at rest and during LV loading (saline infusion) to simulate increased LV filling. Body composition, total blood volume, and heart rate recovery after maximal exercise were also examined. V̇o2max increased in a dose-dependent manner (P < 0.05). At maximal exercise, cardiac output and SV were largest in committed exercisers and Masters athletes (P < 0.05), while arteriovenous oxygen difference was greater in all trained groups (P < 0.05). At maximal exercise, effective arterial elastance, an index of ventricular-arterial coupling, was lower in committed exercisers and Masters athletes (P < 0.05). Doppler measures of LV filling were not enhanced at any condition, irrespective of lifelong exercise frequency. These data suggest that performing four or more weekly endurance exercise sessions over a lifetime results in significant gains in V̇o2max, SV, and heart rate regulation during exercise; however, improved SV regulation during exercise is not coupled with favorable effects on LV filling, even when the heart is fully loaded. PMID:24458750
Huang, Tung-Yi; Lin, Lung-Sheng; Cho, Keng-Chi; Chen, Shean-Jen; Kuo, Yu-Min; Yu, Lung; Wu, Fong-Sen; Chuang, Jih-Ing; Chen, Hsiun-Ing; Jen, Chauying J
2012-09-01
Although exercise usually improves motor performance, the underlying cellular changes in the cerebellum remain to be elucidated. This study aimed to investigate whether and how chronic treadmill exercise in young rats induced Purkinje cell changes to improve motor performance and rendered the cerebellum less vulnerable to toxin insults. After 1-wk familiarization of treadmill running, 6-wk-old male Wistar rats were divided into exercise and sedentary groups. The exercise group was then subjected to 8 wk of exercise training at moderate intensity. The rotarod test was carried out to evaluate motor performance. Purkinje cells in cerebellar slices were visualized by lucifer yellow labeling in single neurons and by calbindin immunostaining in groups of neurons. Compared with sedentary control rats, exercised rats not only performed better in the rotarod task, but also showed finer Purkinje cell structure (higher dendritic volume and spine density with the same dendritic field). The exercise-improved cerebellar functions were further evaluated by monitoring the long-lasting effects of intraventricular application of OX7-saporin. In the sedentary group, OX7-saporin treatment retarded the rotarod performance and induced ∼60% Purkinje cell loss in 3 wk. As a comparison, the exercise group showed much milder injuries in the cerebellum by the same toxin treatment. In conclusion, exercise training in young rats increased the dendritic density of Purkinje cells, which might play an important role in improving the motor performance. Furthermore, as Purkinje cells in the exercise group were relatively toxin resistant, the exercised rats showed good motor performance, even under toxin-treated conditions.
Core stability training: applications to sports conditioning programs.
Willardson, Jeffrey M
2007-08-01
In recent years, fitness practitioners have increasingly recommended core stability exercises in sports conditioning programs. Greater core stability may benefit sports performance by providing a foundation for greater force production in the upper and lower extremities. Traditional resistance exercises have been modified to emphasize core stability. Such modifications have included performing exercises on unstable rather than stable surfaces, performing exercises while standing rather than seated, performing exercises with free weights rather than machines, and performing exercises unilaterally rather than bilaterally. Despite the popularity of core stability training, relatively little scientific research has been conducted to demonstrate the benefits for healthy athletes. Therefore, the purpose of this review was to critically examine core stability training and other issues related to this topic to determine useful applications for sports conditioning programs. Based on the current literature, prescription of core stability exercises should vary based on the phase of training and the health status of the athlete. During preseason and in-season mesocycles, free weight exercises performed while standing on a stable surface are recommended for increases in core strength and power. Free weight exercises performed in this manner are specific to the core stability requirements of sports-related skills due to moderate levels of instability and high levels of force production. Conversely, during postseason and off-season mesocycles, Swiss ball exercises involving isometric muscle actions, small loads, and long tension times are recommended for increases in core endurance. Furthermore, balance board and stability disc exercises, performed in conjunction with plyometric exercises, are recommended to improve proprioceptive and reactive capabilities, which may reduce the likelihood of lower extremity injuries.
Ratamess, Nicholas A; Chiarello, Christina M; Sacco, Anthony J; Hoffman, Jay R; Faigenbaum, Avery D; Ross, Ryan E; Kang, Jie
2012-11-01
The purpose of the present study was to investigate the effects of manipulating rest interval (RI) length of the first upper-body exercise in sequence on subsequent resistance exercise performance. Twenty-two men and women with at least 1 year of resistance training experience performed resistance exercise protocols on 3 occasions in random order. Each protocol consisted of performing 4 barbell upper-body exercises in the same sequence (bench press, incline bench press, shoulder press, and bent-over row) for 3 sets of up to 10 repetitions with 75% of 1 repetition maximum. Bench press RIs were 1, 2, or 3 minutes, whereas other exercises were performed with a standard 2-minute rest interval. The number of repetitions completed, average power, and velocity for each set of each exercise were recorded. Gender differences were observed during the bench press and incline press as women performed significantly (p ≤ 0.05) more repetitions than men during all RIs. The magnitude of decline in velocity and power over 3 sets of the bench press and incline press was significantly higher in men than women. Manipulation of RI length during the bench press did not affect performance of the remaining exercises in men. However, significantly more repetitions were performed by women during the first set of the incline press using 3-minute rest interval than 1-minute rest interval. In men and women, performance of the incline press and shoulder press was compromised compared with baseline performances. Manipulation of RI length of the first exercise affected performance of only the first set of 1 subsequent exercise in women. All RIs led to comparable levels of fatigue in men, indicating that reductions in load are necessary for subsequent exercises performed in sequence that stress similar agonist muscle groups when 10 repetitions are desired.
Kara, Bilge; Küçük, Fadime; Poyraz, Esra Coşkuner; Tomruk, Melda Soysal; İdıman, Egemen
2017-01-01
The aim of our study is to examine effects of aerobic and Pilates exercises on disability, cognition, physical performance, balance, depression and fatigue in relapsing-remitting Multiple Sclerosis (MS) patients as compared to healthy controls. The subjects were divided as aerobic exercise (n = 26), Pilates (n = 9), and the healthy control group (n = 21). We used MSFC, physical performance, Berg balance scale, Beck depression scale, fatigue impact scale. All evaluations were performed before and after exercise training. There are statistically meaningful differences between Nine hole testing, PASAT 3, physical performance and fatique impact scale before and after aerobic exercise. Also we found significant difference for physical performance in the Pilates group. There are no significant differences in measures of fatique impact scale and depression between aerobic exercise group and the healthy controls after exercise. We found significant differences between Pilates and control group's after measurements except depression. There were significant differences between the Pilates and aerobic group for cognitive tests in favor of the Pilates group. Aerobic exercise and clinical Pilates exercises revealed moderate changes in levels of cognitive, physical performance, balance, depression, fatigue in MS patients.
Knowledge and practice of physical exercise among the inhabitants of Bangkok.
Dajpratham, Piyapat; Chadchavalpanichaya, Navaporn
2007-11-01
To study the knowledge and practice of physical exercise among the inhabitants of Bangkok. The factors correlated with knowledge and the practice of physical exercise, were also explored. A self-administered questionnaire was designed to survey 1200 inhabitants in Bangkok and the vicinity aged more than 18 years old. One thousand one hundred and seven people aged ranging from 18-81 years old completed the questionnaires (response rate 92.25%). Six hundred and forty people (58.4%) exercised regularly. The exercise was performed 1-2 days per week with varied duration. They performed exercises alone, in their homes, in the evening. They did not report any expenditure on the exercises. Common types of exercise reported were walking, jogging, attending an aerobic exercise class, using an exercise machine, and callisthenic exercise. Two hundred and seven people (18.9%) did not perform exercise at all because of the lack of time. The factors correlated with regular exercise were the increasing age, the high level of education, the amount of free time per day, and the enjoyment of exercise. With relation to knowledge of exercise, most people lacked knowledge of the benefits of exercise rather than how to do exercise and when to stop exercising. People who had a higher educational level than secondary school and a high income, practiced exercise everyday. They acquired their knowledge of exercise from attending an exercise course. People living in Bangkok usually performed regular exercises of 1-2 days per week with varied duration. The majority lacked knowledge of the benefits of exercise. Educational level of the samples was the only factor correlated with both regular exercise and knowledge of exercise.
A strategic value management approach for energy and maintenance management in a building
NASA Astrophysics Data System (ADS)
Nawi, Mohd Nasrun Mohd; Dahlan, Nofri Yenita; Nadarajan, Santhirasegaran
2015-05-01
Fragmentation process is always been highlighted by the stakeholders in the construction industry as one of the `critical' issue that diminishing the opportunity for stakeholders that involved during the operation and maintenance stage to influence design decisions. Failure of design professionals to consider how a maintenance contractor or facility manager will construct the design thus results in higher operating cost, wastage, defects during the maintenance and operation process. Moving towards team integration is considered a significant strategy for overcoming the issue. Value Management is a style of management dedicated to guiding people and promoting innovation with the aim to improve overall building performance through structured, team-oriented exercises which make explicit, and appraise subsequent decisions, by reference to the value requirements of the clients. Accordingly, this paper discusses the fragmentation issue in more detail including the definition, causes and effects to the maintenance and operation of building and at the same time will highlighted the potential of VM integrated team approach as a strategic management approach for overcoming that issue. It also explores that the team integration strategy alleviates scheduling problems, delays and disputes during the construction process, and, hence, prevent harming the overall building performance.
Montoliu, Patricia; López, Marta; Mascort, Joan; Morales, Carles
2018-01-01
Case summary A 12-year-old neutered male domestic shorthair cat was presented to our referral hospital with a chronic history of tenesmus and lumbosacral pain. A diagnosis of degenerative lumbosacral stenosis (DLSS) was made and a standard dorsal L7–S1 laminectomy was performed uneventfully, with complete recovery within 1 month. The cat was brought back 4 months later for investigation of lumbosacral pain after having suffered a minor traumatic event. Neurological examination identified a low tail carriage, weakness, exercise intolerance, left pelvic limb lameness and diminished withdrawal reflexes in both pelvic limbs with severe sacrocaudal pain. A traumatic facet fracture of the L7 articular processes and subsequent spondylolisthesis was diagnosed. A second surgery was performed to stabilise the region. The cat was normal on neurological examination 1 month later and no further clinical signs were noted. Relevance and novel information This is the first description of a fracture and spondylolisthesis as a possible postoperative complication after L7–S1 dorsal laminectomy in a cat. The case highlights the importance of postoperative changes in the supportive structures of the lumbosacral spine in cats after surgical treatment of DLSS. PMID:29552353
Wollseiffen, Petra; Vogt, Tobias; Strüder, Heiko K; Schneider, Stefan
2018-01-01
The aim of this study was to compare the influence of a class of aerobic exercise and an art class on brain cortical activity and possible effects on cognitive performance. Electroencephalography was used to record the electrocortical activity of 16 schoolchildren (8-10 years old) before and after an aerobic exercise class and an art class. Performance in a standardized test of educational attainment (VERA-3) was assessed following both classes. A significant decrease in cortical activity was detected in all 4 lobes after exercise but not after art classes (p < 0.05). No changes in cognitive performance were observed after exercise and art classes. In this study, cortical activity was reduced after an exercise class but no effect on cognitive performance was observed. Hence, the neurophysiological effect of exercise should be further evaluated regarding different kinds of cognitive performance: creativity, knowledge acquisition as well as the outlasting effects of exercise on academic achievement. © 2017 The Author(s) Published by S. Karger AG, Basel.
Sacco, Guillaume; Caillaud, Corinne; Ben Sadoun, Gregory; Robert, Philippe; David, Renaud; Brisswalter, Jeanick
2016-01-01
Epidemiological studies highlight the relevance of regular exercise interventions to enhance or maintain neurocognitive function in subjects with cognitive impairments. The aim of this study was to ascertain the effect of aerobic exercise associated with cognitive enrichment on cognitive performance in subjects with mild cognitive impairment (MCI). Eight participants with MCI (72 ± 2 years) were enrolled in a 9-month study that consisted of two 3-months experimental interventions separated by a training cessation period of 3 months. The interventions included either aerobic exercise alone or aerobic exercise combined with cognitive enrichment. The exercise program involved two 20-min cycling exercise bouts per week at an intensity corresponding to 60% of the heart rate reserve. Cognitive performance was assessed using a task of single reaction time (SRT) and an inhibition task (Go-no-Go) before, immediately after, and 1 month after each intervention. The exercise intervention improved the speed of responses during the Go-no-Go task without any increase in errors. This improvement was enhanced by cognitive enrichment (6 ± 1% ; p > 0.05), when compared with exercise alone (4 ± 0.5% ,). Following exercise cessation, this positive effect disappeared. No effect was observed on SRT performance. Regular aerobic exercise improved cognitive performance in MCI subjects and the addition of cognitive tasks during exercise potentiated this effect. However, the influence of aerobic exercise on cognitive performance did not persist after cessation of training. Studies involving a larger number of subjects are necessary to confirm these results.
Aerobic exercise enhances neural correlates of motor skill learning.
Singh, Amaya M; Neva, Jason L; Staines, W Richard
2016-03-15
Repetitive, in-phase bimanual motor training tasks can expand the excitable cortical area of the trained muscles. Recent evidence suggests that an acute bout of moderate-intensity aerobic exercise can enhance the induction of rapid motor plasticity at the motor hotspot. However, these changes have not been investigated throughout the entire cortical representation. Furthermore, it is unclear how exercise-induced changes in excitability may relate to motor performance. We investigated whether aerobic exercise could enhance the neural correlates of motor learning. We hypothesized that the combination of exercise and training would increase the excitable cortical area to a greater extent than either exercise or training alone, and that the addition of exercise would enhance performance on a motor training task. 25 young, healthy, right-handed individuals were recruited and divided into two groups and three experimental conditions. The exercise group performed exercise alone (EX) and exercise followed by training (EXTR) while the training group performed training alone (TR). The combination of exercise and training increased excitability within the cortical map of the trained muscle to a greater extent than training alone. However, there was no difference in performance between the two groups. These results indicate that exercise may enhance the cortical adaptations to motor skill learning. Copyright © 2015 Elsevier B.V. All rights reserved.
Rector, R Scott; Loethen, Joanne; Ruebel, Meghan; Thomas, Tom R; Hinton, Pamela S
2009-10-01
Weight loss improves metabolic fitness and reduces morbidity and mortality; however, weight reduction also reduces bone mineral density (BMD) and increases bone turnover. Weight-bearing aerobic exercise may preserve bone mass and maintain normal bone turnover during weight reduction. We investigated the impact of weight-bearing and nonweight-bearing exercise on serum markers of bone formation and breakdown during short-term, modest weight loss in overweight premenopausal women. Subjects (n = 36) were assigned to 1 of 3 weight-loss interventions designed to produce a 5% reduction in body weight over 6 weeks: (i) energy restriction only (n = 11; DIET); (ii) energy restriction plus nonweight-bearing exercise (n = 12, CYCLE); or (iii) energy restriction plus weight-bearing exercise (n = 13, RUN). Bone turnover markers were measured in serum collected at baseline and after weight loss. All groups achieved a ~5% reduction in body weight (DIET = 5.2%; CYCLE = 5.0%; RUN = 4.7%). Osteocalcin (OC) and C-terminal telopeptide of type I collagen (CTX) increased with weight loss in all 3 groups (p < 0.05), whereas bone alkaline phosphatase was unaltered by the weight-loss interventions. At baseline, OC and CTX were positively correlated (r = 0.36, p = 0.03), but the strength of this association was diminished (r = 0.30, p = 0.06) after weight loss. Modest weight loss, regardless of method, resulted in a significant increase in both OC and CTX. Low-impact, weight-bearing exercise had no effect on serum markers of bone formation or resorption in premenopausal women during weight loss. Future studies that examine the effects of high-impact, weight-bearing activity on bone turnover and BMD during weight loss are warranted.
Gender differences in substrate utilisation during exercise.
Ruby, B C; Robergs, R A
1994-06-01
The selection and utilisation of metabolic substrates during endurance exercise are regulated by a complex array of effectors. These factors include, but are not limited to, endurance training and cardiorespiratory fitness, exercise intensity and duration, muscle morphology and histology, hormonal factors and diet. Although the effects of these factors on substrate utilisation patterns are well understood, the variation in substrate utilisation during endurance exercise between males and females is not. Because of the extreme heterogeneity in exercise protocols and individuals studied, the differences in substrate utilisation between males and females remain somewhat inconclusive. Regardless of heterogeneity, if the results from studies are interpreted collectively, an apparent gender difference in the selection and metabolism of substrates can be seen in sedentary individuals. However, this difference between genders diminishes as the level of cardiorespiratory fitness is increased to that of highly trained individuals. During rest and lower intensity exercise, the preferential metabolism of lipid occurs with a concomitant sparing of muscle glycogen. However, as the intensity of exercise is increased, the relative contribution of carbohydrate also increases. The exercise intensity at which the shift from lipid to carbohydrate is determined and regulated by the previously mentioned factors. Because the intensity and duration of exercise play a predominant role, the variation in exercise protocols poses a methodological concern when interpreting previous research. When attempting to compare the metabolism of substrates during endurance exercise, appropriate selection and interpretation of measurement techniques are necessary. Measurement techniques include the nonprotein respiratory exchange ratio, muscle and fat biopsies and the measurement of various blood metabolites, such as free fatty acids and glycerol. Similarly, in vitro analysis of lipolytic activity has also been demonstrated in males and females in response to varying levels of female gonadotrophic hormones. When comparing the substrate utilisation patterns between males and females, the area of hormonal regulation has received less attention. Often the catecholamine response to endurance exercise is measured; however, the gonadotrophic hormones, particularly those of the female, have received less attention when comparing genders. Indeed, the regulatory nature of the female gonadotrophic hormones has been demonstrated. Collectively, the effects of elevated estrogen, as in the luteal phase of menstruation, appear to promote lipolytic activity. Estrogen-mediated lipolytic activation occurs by apparently altering the sensitivity to lipoprotein lipase and by increasing the levels of human growth hormone (somatotropin), an activator of lipolysis.(ABSTRACT TRUNCATED AT 400 WORDS)
Smith, Andrew M.; Spiegler, Kevin M.; Sauce, Bruno; Wass, Christopher D.; Sturzoiu, Tudor; Matzel, Louis D.
2013-01-01
Increases in performance on tests of attention and learning are often observed shortly after a period of aerobic exercise, and evidence suggests that humans who engage in regular exercise are partially protected from age-related cognitive decline. However, the cognitive benefits of exercise are typically short-lived, limiting the practical application of these observations. We explored whether physical exercise would induce lasting changes in general cognitive ability if that exercise was combined with working memory training, which is purported to broadly impact on cognitive performance. Mice received either exercise (six weeks of voluntary running wheel access), working memory training, both treatments, or various control treatments. Near the completion of this period of exercise, working memory training (in a dual radial-arm maze) was initiated (alternating with days of exercise), and was continued for several weeks. Upon completion of these treatments, animals were assessed (2–4 weeks later) for performance on four diverse learning tasks, and the aggregate performance of individual animals across all four learning tasks was estimated. Working memory training alone promoted small increases in general cognitive performance, although any beneficial effects of exercise alone had dissipated by the time of learning assessments. However, the two treatments in combination more than doubled the improvement in general cognitive performance supported by working memory training alone. Unlike the transient effects that acute aerobic exercise can have on isolated learning tasks, these results indicate that an acute period of exercise combined with working memory training can have synergistic and lasting impact on general cognitive performance. PMID:24036169
Development of an Online Toolkit for Measuring Performance in Health Emergency Response Exercises.
Agboola, Foluso; Bernard, Dorothy; Savoia, Elena; Biddinger, Paul D
2015-10-01
Exercises that simulate emergency scenarios are accepted widely as an essential component of a robust Emergency Preparedness program. Unfortunately, the variability in the quality of the exercises conducted, and the lack of standardized processes to measure performance, has limited the value of exercises in measuring preparedness. In order to help health organizations improve the quality and standardization of the performance data they collect during simulated emergencies, a model online exercise evaluation toolkit was developed using performance measures tested in over 60 Emergency Preparedness exercises. The exercise evaluation toolkit contains three major components: (1) a database of measures that can be used to assess performance during an emergency response exercise; (2) a standardized data collection tool (form); and (3) a program that populates the data collection tool with the measures that have been selected by the user from the database. The evaluation toolkit was pilot tested from January through September 2014 in collaboration with 14 partnering organizations representing 10 public health agencies and four health care agencies from eight states across the US. Exercise planners from the partnering organizations were asked to use the toolkit for their exercise evaluation process and were interviewed to provide feedback on the use of the toolkit, the generated evaluation tool, and the usefulness of the data being gathered for the development of the exercise after-action report. Ninety-three percent (93%) of exercise planners reported that they found the online database of performance measures appropriate for the creation of exercise evaluation forms, and they stated that they would use it again for future exercises. Seventy-two percent (72%) liked the exercise evaluation form that was generated from the toolkit, and 93% reported that the data collected by the use of the evaluation form were useful in gauging their organization's performance during the exercise. Seventy-nine percent (79%) of exercise planners preferred the evaluation form generated by the toolkit to other forms of evaluations. Results of this project show that users found the newly developed toolkit to be user friendly and more relevant to measurement of specific public health and health care capabilities than other tools currently available. The developed toolkit may contribute to the further advancement of developing a valid approach to exercise performance measurement.
Beneka, Anastasia G; Malliou, Paraskevi K; Missailidou, Victoria; Chatzinikolaou, Athanasios; Fatouros, Ioannis; Gourgoulis, Vassilios; Georgiadis, Elias
2013-01-01
To determine the time course of performance responses after an acute bout of plyometric exercise combined with high and low intensity weight training, a 3-group (including a control group), repeated-measures design was employed. Changes in performance were monitored through jumping ability by measuring countermovement and squat jumping, and strength performance assessment through isometric and isokinetic testing of knee extensors (at two different velocities). Participants in both experimental groups performed a plyometric protocol consisting of 50 jumps over 50 cm hurdles and 50 drop jumps from a 50 cm plyometric box. Additionally, each group performed two basic weight exercises consisting of leg presses and leg extensions at 90-95% of maximum muscle strength for the high intensity group and 60% of maximum muscle strength for the low intensity group. The results of the study suggest that an acute bout of intense plyometric exercise combined with weight exercise induces time-dependent changes in performance, which are also dependent on the nature of exercise protocol and testing procedures. In conclusion, acute plyometric exercise with weight exercise may induce a substantial decline in jumping performance for as long as 72 hours but not in other forms of muscle strength.
The influence of age and exercise modality on growth hormone bioactivity in women.
Gordon, Scott E; Kraemer, William J; Looney, David P; Flanagan, Shawn D; Comstock, Brett A; Hymer, Wesley C
2014-01-01
Prior research has indicated that the loss of skeletal muscle mass and bone mineral density observed with aging is related to the prominent age-related decline in the concentration of serum growth hormone (GH). However, there is limited data on the effects of aging on GH responses to acute bouts of heavy resistance exercise (HRE) and aerobic exercise (AE). The present investigation examined the effects of a HRE protocol and an AE protocol on immunoreactive GH (IGH) and bioactive GH (BGH) in active young and old women. Older women had a diminished serum IGH response to both the HRE and AE protocols compared to the younger women, however a similar response was not observed in serum BGH. Additionally, the HRE protocol elicited a greater BGH response than the AE protocol exclusively in the younger group. Regardless of exercise mode, aging induces an increase in growth hormone polymerization that specifically results in a loss of serum growth hormone immunoreactivity without a concurrent loss of serum growth hormone bioactivity. The greater BGH response to the HRE protocol found in the younger group can be attributed to an unknown serum factor of molecular weight between 30 and 55kD that either potentiated growth hormone bioactivity in response to HRE or inhibited growth hormone bioactivity in response to AE. Copyright © 2014 Elsevier Ltd. All rights reserved.
Veasey, R C; Gonzalez, J T; Kennedy, D O; Haskell, C F; Stevenson, E J
2013-09-01
The current study assessed the interactive effect of breakfast and exercise on cognition and mood. Twelve active males completed four trials; no breakfast-rest, breakfast-rest, no breakfast-exercise or breakfast-exercise in a randomized, cross-over design. The trials consisted of; breakfast or fast, a 2h rest, exercise (treadmill run) or equivalent rest, a chocolate milk drink, a 90 min rest and an ad libitum lunch. Cognitive performance and mood were recorded frequently throughout each trial. Data was analysed as pre-exercise/rest, during and immediately post exercise/rest and post-drink. No effects were found prior to consumption of the drink. Post-drink, fasting before exercise increased mental fatigue compared to consuming breakfast before exercise and fasting before rest. Tension increased when breakfast was consumed at rest and when exercise was undertaken fasted compared to omitting breakfast before rest. Breakfast before rest decreased rapid visual information processing task speed and impaired Stroop performance. Breakfast omission improved Four Choice Reaction Time performance. To conclude, breakfast before exercise appeared beneficial for post-exercise mood even when a post-exercise snack was consumed. Exercise reversed post-breakfast cognitive impairment in active males. Copyright © 2013 Elsevier Ltd. All rights reserved.
Yang, Wenting; Wang, Dongmei; Lei, Zhoujixin; Wang, Chunhui; Chen, Shanguang
2017-12-01
Astronauts who are exposed to weightless environment in long-term spaceflight might encounter bone density and mass loss for the mechanical stimulus is smaller than normal value. This study built a three dimensional model of human femur to simulate the remodeling process of human femur during bed rest experiment based on finite element analysis (FEA). The remodeling parameters of this finite element model was validated after comparing experimental and numerical results. Then, the remodeling process of human femur in weightless environment was simulated, and the remodeling function of time was derived. The loading magnitude and loading cycle on human femur during weightless environment were increased to simulate the exercise against bone loss. Simulation results showed that increasing loading magnitude is more effective in diminishing bone loss than increasing loading cycles, which demonstrated that exercise of certain intensity could help resist bone loss during long-term spaceflight. At the end, this study simulated the bone recovery process after spaceflight. It was found that the bone absorption rate is larger than bone formation rate. We advise that astronauts should take exercise during spaceflight to resist bone loss.
Hsiao, Ya-Hsin; Shin, Miao-Ling; Huang, Cyong-Pei; Chen, Siang-Jyun; Huang, Tsuey-Yuan
2017-06-01
Patients who undergo new arteriovenous fistula (AVF) construction as part of their hemodialysis treatment program are required to perform hand exercises properly in order to maintain AVF function. However, poor performance of these hand exercises currently results in the failure of many patients to preserve AVF function. To increase the rate of performing this hand exercise properly from 55% to 80%. A comprehensive investigation identified the following five main problems: (a) Insufficient muscular endurance; (b) Resistance was not labeled on the ball; (c) Difficulties with maintaining a grip on the ball during the exercise; (d) Lack of standardized education procedures; and (e) Nurses lack latest knowledge on the hand exercise. The strategies used to improve the situation included: (a) Interdisciplinary team cooperation with physiotherapists to design individualized resistance training regimens; (b) Exercise tool improvement; (c) Standardized AVF care; (d) Continuous education for nursing staffs; and (e) Seed teacher program for hand exercise. The rate of proper hand exercise performance increased from 55% to 93%. This nursing project involved an interdisciplinary team that included physiotherapists in order to successfully improve the rate at which the hand exercise was performed properly. This positive experience may be applied to other hemodialysis departments in the treatment of patients with AVF.
Davidson, E J; Martin, B B; Boston, R C; Parente, E J
2011-01-01
Although well documented in racehorses, there is paucity in the literature regarding the prevalence of dynamic upper airway abnormalities in nonracing performance horses. To describe upper airway function of nonracing performance horses with abnormal respiratory noise and/or poor performance via exercising upper airway videoendoscopy. Medical records of nonracing performance horses admitted for exercising evaluation with a chief complaint of abnormal respiratory noise and/or poor performance were reviewed. All horses had video recordings of resting and exercising upper airway endoscopy. Relationships between horse demographics, resting endoscopic findings, treadmill intensity and implementation of head and neck flexion during exercise with exercising endoscopic findings were examined. Dynamic upper airway obstructions were observed in 72% of examinations. Head and neck flexion was necessary to obtain a diagnosis in 21 horses. Pharyngeal wall collapse was the most prevalent upper airway abnormality, observed in 31% of the examinations. Complex abnormalities were noted in 27% of the examinations. Resting laryngeal dysfunction was significantly associated with dynamic arytenoid collapse and the odds of detecting intermittent dorsal displacement of the soft palate (DDSP) during exercise in horses with resting DDSP was only 7.7%. Exercising endoscopic observations were different from the resting observations in 54% of examinations. Dynamic upper airway obstructions were common in nonracing performance horses with respiratory noise and/or poor performance. Resting endoscopy was only helpful in determining exercising abnormalities with recurrent laryngeal neuropathy. This study emphasises the importance of exercising endoscopic evaluation in nonracing performance horses with abnormal respiratory noise and/or poor performance for accurate assessment of dynamic upper airway function. © 2010 EVJ Ltd.
Can the use of creatine supplementation attenuate muscle loss in cachexia and wasting?
Sakkas, Giorgos K; Schambelan, Morris; Mulligan, Kathleen
2009-11-01
Weight loss and low BMI due to an underlying illness have been associated with increased mortality, reduced functional capacity, and diminished quality of life. There is a need for well tolerated, long-term approaches to maintain body weight in patients with cachexia or wasting. The purpose of this review is to highlight the scientific and clinical evidence derived from the recent literature investigating the rationale for and potential medical use of creatine supplementation in patients with cachexia or wasting. Some studies have demonstrated that supplementation with creatine can increase creatine reserves in skeletal muscle and increase muscle mass and performance in various disease states that affect muscle size and function. The mechanisms underlying these effects are not clear. It has been suggested that creatine supplementation may increase intramuscular phosphocreatine stores and promote more rapid recovery of adenosine triphosphate levels following exercise, thus allowing users to exercise for longer periods or at higher intensity levels. Other hypothesized mechanisms include attenuation of proinflammatory cytokines, stimulation of satellite cell proliferation and upregulation of genes that promote protein synthesis and cell repair. Creatine is a generally well tolerated, low-cost, over-the-counter nutritional supplement that shows potential in improving lean body mass and functionality in patients with wasting diseases. However, placebo-controlled studies have shown variable effects, with improvements in some and not in others. Additional studies with longer follow-up are required to identify the populations that might benefit most from creatine supplementation.
Retrospective Analysis of Inflight Exercise Loading and Physiological Outcomes
NASA Technical Reports Server (NTRS)
Ploutz-Snyder, L. L.; Buxton, R. E.; De Witt, J. K.; Guilliams, M. E.; Hanson, A. M.; Peters, B. T.; Pandorf, M. M. Scott; Sibonga, J. D.
2014-01-01
Astronauts perform exercise throughout their missions to counter the health declines that occur as a result of long-term exposure to weightlessness. Although all astronauts perform exercise during their missions, the specific prescriptions, and thus the mechanical loading, differs among individuals. For example, inflight ground reaction force data indicate that subject-specific differences exist in foot forces created when exercising on the second-generation treadmill (T2) [1]. The current exercise devices allow astronauts to complete prescriptions at higher intensities, resulting in greater benefits with increased efficiency. Although physiological outcomes have improved, the specific factors related to the increased benefits are unknown. In-flight exercise hardware collect data that allows for exploratory analyses to determine if specific performance factors relate to physiological outcomes. These analyses are vital for understanding which components of exercise are most critical for optimal human health and performance. The relationship between exercise performance variables and physiological changes during flight has yet to be fully investigated. Identifying the critical performance variables that relate to improved physiological outcomes is vital for creating current and future exercise prescriptions to optimize astronaut health. The specific aims of this project are: 1) To quantify the exercise-related mechanical loading experienced by crewmembers on T2 and ARED during their mission on ISS; 2) To explore relationships between exercise loading variables, bone, and muscle health changes during the mission; 3) To determine if specific mechanical loading variables are more critical than others in protecting physiology; 4) To develop methodology for operational use in monitoring accumulated training loads during crew exercise programs. This retrospective analysis, which is currently in progress, is being conducted using data from astronauts that have flown long-duration missions onboard the ISS and have had access to exercise on the T2 and the Advanced Resistive Exercise Device (ARED). The specific exercise prescriptions vary for each astronaut. General exercise summary metrics will be developed to quantify exercise intensities, volumes, and durations for each subject. Where available, ground reaction force data will be used to quantify mechanical loading experienced by each astronaut. These inflight exercise metrics will be investigated relative to changes in pre- to post-flight bone and muscle health to identify which specific variables are related with improved or degraded physiological outcomes. The information generated from this analysis will fill gaps related to typical bone loading characterization, exercise performance capability, exercise volume and efficiency, and importance of exercise hardware. In addition, methods for quantification of exercise loading for use in monitoring the exercise programs during future space missions will be explored with the intent to inform exercise scientists and trainers as to the critical aspects of inflight exercise prescriptions.
2012-01-01
Background Disaster medicine is a fairly young scientific discipline and there is a need for the development of new methods for evaluation and research. This includes full-scale disaster exercisers. A standardized concept on how to evaluate these exercises, could lead to easier identification of pitfalls caused by system-errors in the organization. The aim of this study was to demonstrate the feasibility of using a combination of performance and outcome indicators so that results can be compared in standardized full-scale exercises. Methods Two multidisciplinary, full-scale exercises were studied in 2008 and 2010. The panorama had the same setup. Sets of performance indicators combined with indicators for unfavorable patient outcome were recorded in predesigned templates. Evaluators, all trained in a standardized way at a national disaster medicine centre, scored the results on predetermined locations; at the scene, at hospital and at the regional command and control. Results All data regarding the performance indicators of the participants during the exercises were obtained as well as all data regarding indicators for patient outcome. Both exercises could therefore be compared regarding performance (processes) as well as outcome indicators. The data from the performance indicators during the exercises showed higher scores for the prehospital command in the second exercise 15 points and 3 points respectively. Results from the outcome indicators, patient survival and patient complications, demonstrated a higher number of preventable deaths and a lower number of preventable complications in the exercise 2010. In the exercise 2008 the number of preventable deaths was lower and the number of preventable complications was higher. Conclusions Standardized multidisciplinary, full-scale exercises in different settings can be conducted and evaluated with performance indicators combined with outcome indicators enabling results from exercises to be compared. If exercises are performed in a standardized way, results may serve as a basis for lessons learned. Future use of the same concept using the combination of performance indicators and patient outcome indicators may demonstrate new and important evidence that could lead to new and better knowledge that also may be applied during real incidents. PMID:22929479
Rådestad, Monica; Nilsson, Heléne; Castrén, Maaret; Svensson, Leif; Rüter, Anders; Gryth, Dan
2012-08-28
Disaster medicine is a fairly young scientific discipline and there is a need for the development of new methods for evaluation and research. This includes full-scale disaster exercisers. A standardized concept on how to evaluate these exercises, could lead to easier identification of pitfalls caused by system-errors in the organization. The aim of this study was to demonstrate the feasibility of using a combination of performance and outcome indicators so that results can be compared in standardized full-scale exercises. Two multidisciplinary, full-scale exercises were studied in 2008 and 2010. The panorama had the same setup. Sets of performance indicators combined with indicators for unfavorable patient outcome were recorded in predesigned templates. Evaluators, all trained in a standardized way at a national disaster medicine centre, scored the results on predetermined locations; at the scene, at hospital and at the regional command and control. All data regarding the performance indicators of the participants during the exercises were obtained as well as all data regarding indicators for patient outcome. Both exercises could therefore be compared regarding performance (processes) as well as outcome indicators. The data from the performance indicators during the exercises showed higher scores for the prehospital command in the second exercise 15 points and 3 points respectively. Results from the outcome indicators, patient survival and patient complications, demonstrated a higher number of preventable deaths and a lower number of preventable complications in the exercise 2010. In the exercise 2008 the number of preventable deaths was lower and the number of preventable complications was higher. Standardized multidisciplinary, full-scale exercises in different settings can be conducted and evaluated with performance indicators combined with outcome indicators enabling results from exercises to be compared. If exercises are performed in a standardized way, results may serve as a basis for lessons learned. Future use of the same concept using the combination of performance indicators and patient outcome indicators may demonstrate new and important evidence that could lead to new and better knowledge that also may be applied during real incidents.
Kim, Yong-Youn; Park, Si-Eun
2016-01-01
[Purpose] The purpose of this study was to assess the effect of whole-body vibration exercise and plyometric exercise on female volleyball players. [Subjects and Methods] Subjects were randomly allocated to two exercise groups (whole-body vibration exercise group and plyometric exercise group). The exercise was conducted three times each week for 8 weeks. Isokinetic muscular strength, jumping performance, and balance were measured before starting the exercise and after finishing the 8 weeks of exercise. [Results] Measurements of isokinetic muscular strength revealed that the whole-body vibration exercise group showed significant increase after the exercise. However, the plyometric exercise group had no significant increase in lumbar flexion, extension, and knee flexion. Measurements of vertical jumping revealed that, the whole-body vibration exercise group had no significant increase after the exercise. However, the plyometric exercise group showed significant increase. Measurements of balance revealed that, the whole-body vibration exercise group showed significant increase. However, the plyometric exercise group showed no significant increase. [Conclusion] Although both whole-body vibration and plyometric exercises are effective intervention methods, the two methods have different effects on the improvement of isokinetic muscular strength, jumping performance, and balance of female volleyball players. PMID:27942136
Kim, Yong-Youn; Park, Si-Eun
2016-11-01
[Purpose] The purpose of this study was to assess the effect of whole-body vibration exercise and plyometric exercise on female volleyball players. [Subjects and Methods] Subjects were randomly allocated to two exercise groups (whole-body vibration exercise group and plyometric exercise group). The exercise was conducted three times each week for 8 weeks. Isokinetic muscular strength, jumping performance, and balance were measured before starting the exercise and after finishing the 8 weeks of exercise. [Results] Measurements of isokinetic muscular strength revealed that the whole-body vibration exercise group showed significant increase after the exercise. However, the plyometric exercise group had no significant increase in lumbar flexion, extension, and knee flexion. Measurements of vertical jumping revealed that, the whole-body vibration exercise group had no significant increase after the exercise. However, the plyometric exercise group showed significant increase. Measurements of balance revealed that, the whole-body vibration exercise group showed significant increase. However, the plyometric exercise group showed no significant increase. [Conclusion] Although both whole-body vibration and plyometric exercises are effective intervention methods, the two methods have different effects on the improvement of isokinetic muscular strength, jumping performance, and balance of female volleyball players.
ERIC Educational Resources Information Center
Chang, Yu-Kai; Etnier, Jennifer L.; Barella, Lisa A.
2009-01-01
Although a generally positive effect of acute exercise on cognitive performance has been demonstrated, the specific nature of the relationship between exercise-induced arousal and cognitive performance remains unclear. This study was designed to identify the relationship between exercise-induced arousal and cognitive performance for the central…
Ormsbee, Michael J; Bach, Christopher W; Baur, Daniel A
2014-04-29
Endurance athletes rarely compete in the fasted state, as this may compromise fuel stores. Thus, the timing and composition of the pre-exercise meal is a significant consideration for optimizing metabolism and subsequent endurance performance. Carbohydrate feedings prior to endurance exercise are common and have generally been shown to enhance performance, despite increasing insulin levels and reducing fat oxidation. These metabolic effects may be attenuated by consuming low glycemic index carbohydrates and/or modified starches before exercise. High fat meals seem to have beneficial metabolic effects (e.g., increasing fat oxidation and possibly sparing muscle glycogen). However, these effects do not necessarily translate into enhanced performance. Relatively little research has examined the effects of a pre-exercise high protein meal on subsequent performance, but there is some evidence to suggest enhanced pre-exercise glycogen synthesis and benefits to metabolism during exercise. Finally, various supplements (i.e., caffeine and beetroot juice) also warrant possible inclusion into pre-race nutrition for endurance athletes. Ultimately, further research is needed to optimize pre-exercise nutritional strategies for endurance performance.
Ormsbee, Michael J.; Bach, Christopher W.; Baur, Daniel A.
2014-01-01
Endurance athletes rarely compete in the fasted state, as this may compromise fuel stores. Thus, the timing and composition of the pre-exercise meal is a significant consideration for optimizing metabolism and subsequent endurance performance. Carbohydrate feedings prior to endurance exercise are common and have generally been shown to enhance performance, despite increasing insulin levels and reducing fat oxidation. These metabolic effects may be attenuated by consuming low glycemic index carbohydrates and/or modified starches before exercise. High fat meals seem to have beneficial metabolic effects (e.g., increasing fat oxidation and possibly sparing muscle glycogen). However, these effects do not necessarily translate into enhanced performance. Relatively little research has examined the effects of a pre-exercise high protein meal on subsequent performance, but there is some evidence to suggest enhanced pre-exercise glycogen synthesis and benefits to metabolism during exercise. Finally, various supplements (i.e., caffeine and beetroot juice) also warrant possible inclusion into pre-race nutrition for endurance athletes. Ultimately, further research is needed to optimize pre-exercise nutritional strategies for endurance performance. PMID:24787031
English, Brett A.; Appalsamy, Martin; Diedrich, Andre; Ruggiero, Alicia M.; Lund, David; Wright, Jane; Keller, Nancy R.; Louderback, Katherine M.; Robertson, David
2010-01-01
Healthy cardiovascular function relies on a balanced and responsive integration of noradrenergic and cholinergic innervation of the heart. High-affinity choline uptake by cholinergic terminals is pivotal for efficient ACh production and release. To date, the cardiovascular impact of diminished choline transporter (CHT) expression has not been directly examined, largely due to the transporter's inaccessibility in vivo. Here, we describe findings from cardiovascular experiments using transgenic mice that bear a CHT genetic deficiency. Whereas CHT knockout (CHT−/−) mice exhibit early postnatal lethality, CHT heterozygous (CHT+/−) mice survive, grow, and reproduce normally and exhibit normal spontaneous behaviors. However, the CHT+/− mouse heart displays significantly reduced levels of high-affinity choline uptake accompanied by significantly reduced levels of ACh. Telemeterized recordings of cardiovascular function in these mice revealed tachycardia and hypertension at rest. After treadmill exercise, CHT+/− mice exhibited slower heart rate recovery, consistent with a diminished cholinergic reserve, a contention validated through direct vagal nerve stimulation. Echocardiographic and histological experiments revealed an age-dependent decrease in fractional shortening, increased left ventricular dimensions, and increased ventricular fibrosis, consistent with ventricular dysfunction. These cardiovascular phenotypes of CHT+/− mice encourage an evaluation of humans bearing reduced CHT expression for their resiliency in maintaining proper heart function as well as risk for cardiovascular disease. PMID:20601463
Grabowski, Patrick; Wilson, John; Walker, Alyssa; Enz, Dan; Wang, Sijian
2017-01-01
Demonstrate implementation, safety and feasibility of multimodal, impairment-based physical therapy (PT) combining vestibular/oculomotor and cervical rehabilitation with sub-symptom threshold exercise for the treatment of patients with post-concussion syndrome (PCS). University hospital outpatient sports medicine facility. Twenty-five patients (12-20 years old) meeting World Health Organization criteria for PCS following sport-related concussion referred for supervised PT consisting of sub-symptom cardiovascular exercise, vestibular/oculomotor and cervical spine rehabilitation. Retrospective cohort. Post-Concussion Symptom Scale (PCSS) total score, maximum symptom-free heart rate (SFHR) during graded exercise testing (GXT), GXT duration, balance error scoring system (BESS) score, and number of adverse events. Patients demonstrated a statistically significant decreasing trend (p < 0.01) for total PCSS scores (pre-PT M = 18.2 (SD = 14.2), post-PT M = 9.1 (SD = 10.8), n = 25). Maximum SFHR achieved on GXT increased 23% (p < 0.01, n = 14), and BESS errors decreased 52% (p < 0.01, n = 13). Two patients reported mild symptom exacerbation with aerobic exercise at home, attenuated by adjustment of the home exercise program. Multimodal, impairment-based PT is safe and associated with diminishing PCS symptoms. This establishes feasibility for future clinical trials to determine viable treatment approaches to reduce symptoms and improve function while avoiding negative repercussions of physical inactivity and premature return to full activity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Comparable Neutrophil Responses for Arm and Intensity-matched Leg Exercise.
Leicht, Christof A; Goosey-Tolfrey, Victoria L; Bishop, Nicolette C
2017-08-01
Arm exercise is performed at lower absolute intensities than lower body exercise. This may impact on intensity-dependent neutrophil responses, and it is unknown whether individuals restricted to arm exercise experience the same changes in the neutrophil response as found for lower body exercise. Therefore, we aimed to investigate the importance of exercise modality and relative exercise intensity on the neutrophil response. Twelve moderately trained men performed three 45-min constant load exercise trials after determination of peak oxygen uptake for arm exercise (V˙O2peak arms) and cycling (V˙O2peak legs): 1) arm cranking exercise at 60% V˙O2peak arms, 2) moderate cycling at 60% V˙O2peak legs, and 3) easy cycling at 60% V˙O2peak arms. Neutrophil numbers in the circulation increased for all exercise trials, but were significantly lower for easy cycling when compared with arm exercise (P = 0.009), mirroring the blunted increase in HR and epinephrine during easy cycling. For all trials, exercising HR explained some of the variation of the neutrophil number 2 h postexercise (R = 0.51-0.69), epinephrine explaining less of this variation (R = 0.21-0.34). The number of neutrophils expressing CXCR2 decreased in the recovery from exercise in all trials (P < 0.05). Arm and leg exercise elicits the same neutrophil response when performed at the same relative intensity, implying that populations restricted to arm exercise might achieve a similar exercise induced neutrophil response as those performing lower body exercise. A likely explanation for this is the higher sympathetic activation and cardiac output for arm and relative intensity-matched leg exercise when compared with easy cycling, which is partly reflected in HR. This study further shows that the downregulation of CXCR2 may be implicated in exercise-induced neutrophilia.
Autophagy Is a Promoter for Aerobic Exercise Performance during High Altitude Training
Zhang, Ying
2018-01-01
High altitude training is one of the effective strategies for improving aerobic exercise performance at sea level via altitude acclimatization, thereby improving oxygen transport and/or utilization. But its underlying molecular mechanisms on physiological functions and exercise performance of athletes are still vague. More recent evidence suggests that the recycling of cellular components by autophagy is an important process of the body involved in the adaptive responses to exercise. Whether high altitude training can activate autophagy or whether high altitude training can improve exercise performance through exercise-induced autophagy is still unclear. In this narrative review article, we will summarize current research advances in the improvement of exercise performance through high altitude training and its reasonable molecular mechanisms associated with autophagy, which will provide a new field to explore the molecular mechanisms of adaptive response to high altitude training. PMID:29849885
Walliczek-Dworschak, U; Schmitt, M; Dworschak, P; Diogo, I; Ecke, A; Mandapathil, M; Teymoortash, A; Güldner, C
2017-06-01
Increasing usage of robotic surgery presents surgeons with the question of how to acquire the special skills required. This study aimed to analyze the effect of different exercises on their performance outcomes. This prospective study was conducted on the da Vinci Skills Simulator from December 2014 till August 2015. Sixty robotic novices were included and randomized to three groups of 20 participants each. Each group performed three different exercises with comparable difficulty levels. The exercises were performed three times in a row within two training sessions, with an interval of 1 week in between. On the final training day, two new exercises were added and a questionnaire was completed. Technical metrics of performance (overall score, time to complete, economy of motion, instrument collisions, excessive instrument force, instruments out of view, master work space range, drops, missed targets, misapplied energy time, blood loss and broken vessels) were recorded by the simulator software for further analysis. Training with different exercises led to comparable results in performance metrics for the final exercises among the three groups. A significant skills gain was recorded between the first and last exercises, with improved performance in overall score, time to complete and economy of motion for all exercises in all three groups. As training with different exercises led to comparable results in robotic training, the type of exercise seems to play a minor role in the outcome. For a robotic training curriculum, it might be important to choose exercises with comparable difficulty levels. In addition, it seems to be advantageous to limit the duration of the training to maintain the concentration throughout the entire session.
Energy replacement diminishes the effect of exercise on postprandial lipemia in boys.
Thackray, Alice E; Barrett, Laura A; Tolfrey, Keith
2016-04-01
Acute bouts of exercise reduce postprandial triacylglycerol concentrations ([TAG]) in healthy boys and girls; however, it is not known whether this effect is mediated by the energy deficit. This study examined whether the exercise-induced reduction in postprandial [TAG] persists after immediate dietary replacement of the exercise energy expenditure (EE). Eighteen healthy 11- to 13-year-old boys (mean (SD): body mass 41.3 (8.4)kg; peak oxygen uptake (V̇O2) 55 (5)mL·kg(-1)·min(-1)) completed three, 2-day conditions in a within-measures, crossover design separated by 14days. On day 1, participants rested (CON), exercised at 60% peak V̇O2 inducing a net EE of 32kJ·kg(-1) body mass (EX-DEF) or completed the same exercise with the net EE replaced immediately (EX-REP). On day 2, capillary blood samples were taken in the fasted state and at pre-determined intervals throughout the 6.5h postprandial period. A standardised breakfast and lunch meal were consumed immediately and 4h, respectively, after the fasting sample. Based on ratios of the geometric means (95% confidence intervals (CI) for ratios), EX-DEF fasting [TAG] was 19% and 15% lower than CON (-32 to -4%, ES=1.15, P=0.02) and EX-REP (-29 to 0%, ES=0.91, P=0.05) respectively; CON and EX-REP were similar (-4%; P=0.59). The EX-DEF total area under the [TAG] versus time curve was 15% and 16% lower than CON (-27 to 0%, ES=0.55, P=0.05) and EX-REP (-29 to -2%, ES=0.62, P=0.03) respectively; CON and EX-REP were not different (2%; -13 to 20%, P=0.80). Immediate replacement of the exercise-induced energy deficit negates the reduction in postprandial [TAG] in boys; this highlights the importance of maintaining a negative energy balance immediately post-exercise to maximise the metabolic health benefits of exercise. Copyright © 2016 Elsevier Inc. All rights reserved.
Faber, Mathilde; Andersen, Malene H; Sevel, Claus; Thorborg, Kristian; Bandholm, Thomas; Rathleff, Michael
2015-01-01
Introduction. Time-under-tension (TUT) reflects time under load during strength training and is a proxy of the total exercise dose during strength training. The purpose of this study was to investigate if young participants are able to reproduce TUT and exercise form after two weeks of unsupervised exercises. Material and Methods. The study was an assessor-blinded intervention study with 29 participants. After an initial instruction, all participants were instructed to perform two weeks of home-based unsupervised shoulder abduction exercises three times per week with an elastic exercise band. The participants were instructed in performing an exercise with a predefined TUT (3 s concentric; 2 s isometric; 3 s eccentric; 2 s break) corresponding to a total of 240 s of TUT during three sets of 10 repetitions. After completing two weeks of unsupervised home exercises, they returned for a follow-up assessment of TUT and exercise form while performing the shoulder abduction exercise. A stretch sensor attached to the elastic band was used to measure TUT at baseline and follow-up. A physiotherapist used a pre-defined clinical observation protocol to determine if participants used the correct exercise form. Results. Fourteen of the 29 participants trained with the instructed TUT at follow-up (predefined target: 240 s ±8%). Thirteen of the 29 participants performed the shoulder abduction exercise with a correct exercise form. Seven of the 29 participants trained with the instructed TUT and exercise form at follow-up. Conclusion. The majority of participants did not use the instructed TUT and exercise form at follow-up after two weeks of unsupervised exercises. These findings emphasize the importance of clear and specific home exercise instructions if participants are to follow the given exercise prescription regarding TUT and exercise form as too many or too few exercise stimuli in relation to the initially prescribed amount of exercise most likely will provide a misinterpretation of the actual effect of any given specific home exercise intervention.
Rathleff, Michael S; Bandholm, Thomas; McGirr, Kate A; Harring, Stine I; Sørensen, Anders S; Thorborg, Kristian
2016-07-01
Is the exercise-integrated Bandcizer™ system feasible for recording exercise dosage (time under tension (TUT) and repetitions) and pain scores among adolescents with patellofemoral pain? Do adolescents practise the exercises as prescribed (TUT and repetitions)? Do adolescents accurately report the exercises they do in an exercise diary? Observational feasibility study. Twenty adolescents between 15 and 19 years of age with patellofemoral pain. Participants were prescribed three exercise sessions per week (one with and two without supervision) for 6 weeks. The exercises included three hip and one knee exercise with an elastic resistance band. Participants were instructed to perform three sets with a predefined TUT (3seconds concentric; 2seconds isometric; 3seconds eccentric; 2seconds pause), equating to 80seconds for 10 repetitions (one set). The exercise-integrated system consisted of a sensor attached to the elastic resistance band that was connected to the Bandtrainer app on an electronic tablet device. Pain intensity was reported on a visual analogue scale on the app. Participants also completed a self-report exercise diary. No major problems were reported with the system. Participants performed 2541 exercise sets during the 6 weeks; 5% were performed with the predefined TUT (ie, within 10seconds of the 80-second target) and 90% were performed below the target TUT. On average, the participants received 15% of the instructed exercise dosage based on TUT. The exercise dosage reported in the exercise diaries was 2.3 times higher than the TUT data from the electronic system. Pain intensity was successfully collected in 100% of the exercise sets. The system was feasible for adolescents with patellofemoral pain. The system made it possible to capture detailed data about the TUT, repetitions and sets during home-based exercises together with pain intensity before and after each exercise. [Rathleff MS, Bandholm T, McGirr KA, Harring SI, Sørensen AS, Thorborg K (2016) New exercise-integrated technology can monitor the dosage and quality of exercise performed against an elastic resistance band by adolescents with patellofemoral pain: an observational study.Journal of Physiotherapy62: 159-163]. Copyright © 2016 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.
Chopp-Hurley, Jaclyn N; Brenneman, Elora C; Wiebenga, Emily G; Bulbrook, Brittany; Keir, Peter J; Maly, Monica R
2017-06-01
The aim of this study was to evaluate the effectiveness of a 12-week workplace exercise program on work ability, performance, and patient-reported symptoms in older university employees with knee and/or hip osteoarthritis. Twenty-four participants with clinical hip and/or knee osteoarthritis were randomized to exercise or no exercise. At baseline and follow-up, several work (work ability, resilience), patient-reported (pain, physical function, depressive symptoms, self-efficacy), and performance outcomes (hip and knee strength, mobility performance) were measured. Significant improvements in work ability (P < 0.049) and patient-reported outcomes (pain, function, depressive symptoms) existed in the exercise group. No improvements were demonstrated in the no exercise group. Exercise in the workplace improved work ability and patient-reported symptoms in older workers with osteoarthritis. The benefits of workplace exercise programs should be studied in a larger sample in which attention is given to improving exercise adherence.
Keen, Douglas A; Constantopoulos, Eleni; Konhilas, John P
2016-01-01
Dehydration caused by prolonged exercise impairs thermoregulation, endurance and exercise performance. Evidence from animal and human studies validates the potential of desalinated deep-ocean mineral water to positively impact physiological and pathophysiological conditions. Here, we hypothesize that deep-ocean mineral water drawn from a depth of 915 m off the Kona, HI coast enhances recovery of hydration and exercise performance following a dehydrating exercise protocol compared to mountain spring water and a carbohydrate-based sports drink. Subjects (n = 8) were exposed to an exercise-dehydration protocol (stationary biking) under warm conditions (30 °C) to achieve a body mass loss of 3 % (93.4 ± 21.7 total exercise time). During the post-exercise recovery period, subjects received deep-ocean mineral water (Kona), mountain spring water (Spring) or a carbohydrate-based sports drink (Sports) at a volume (in L) equivalent to body mass loss (in Kg). Salivary samples were collected at regular intervals during exercise and post-exercise rehydration. Additionally, each participant performed peak torque knee extension as a measure of lower body muscle performance. Subjects who received Kona during the rehydrating period showed a significantly more rapid return to pre-exercise (baseline) hydration state, measured as the rate of decline in peak to baseline salivary osmolality, compared to Sports and Spring groups. In addition, subjects demonstrated significantly improved recovery of lower body muscle performance following rehydration with Kona versus Sports or Spring groups. Deep-ocean mineral water shows promise as an optimal rehydrating source over spring water and/or sports drink.
Oberste, Max; Hartig, Philipp; Bloch, Wilhelm; Elsner, Benjamin; Predel, Hans-Georg; Ernst, Bernhard; Zimmer, Philipp
2017-01-01
Introduction: Many studies report improvements in cognitive performance following acute endurance exercise compared to control group treatment. These cognitive benefits are interpreted as a result of a physiological response to exercise. However, it was also hypothesized that expectation-driven placebo effects account for these positive effects. The purpose of this study was to investigate the differences between expectations for cognitive benefits toward acute endurance exercise and multiple control group treatments. Methods: Healthy individuals ( N = 247, 24.26 ± 3.88 years) were randomized to eight different groups watching videos of a moderate, a vigorous exercise treatment or one control group treatment (waiting, reading, video-watching, stretching, myofascial release workout, and very light exercise). Then, they were introduced to three commonly used cognitive test procedures in acute exercise-cognition research (Stroop-test, Trail-Making-test, Free-recall-task). Participants rated the effect they would expect on their performance in those tasks, if they had received the treatment shortly before the task, on an 11-point Likert scale. Results: No significantly different expectations for cognitive benefits toward acute moderate exercise and control group treatments could be revealed. Participants expected significantly worse performance following vigorous exercise compared to following waiting and stretching for all cognitive tests. Significantly worse performance after vigorous exercise compared to after very light exercise was expected for Stroop and Free-recall. For Free-recall, participants expected worse performance after vigorous exercise compared to myofascial release training as well. Conclusion: Our results indicate that expectation-driven placebo effects are unlikely to cause the reported greater cognitive improvements following acute moderate and vigorous endurance exercise compared to following common control group treatments.
Exercise training for intermittent claudication.
McDermott, Mary M
2017-11-01
The objective of this study was to provide an overview of evidence regarding exercise therapies for patients with lower extremity peripheral artery disease (PAD). This manuscript summarizes the content of a lecture delivered as part of the 2016 Crawford Critical Issues Symposium. Multiple randomized clinical trials demonstrate that supervised treadmill exercise significantly improves treadmill walking performance in people with PAD and intermittent claudication symptoms. A meta-analysis of 25 randomized trials demonstrated a 180-meter increase in treadmill walking distance in response to supervised exercise interventions compared with a nonexercising control group. Supervised treadmill exercise has been inaccessible to many patients with PAD because of lack of medical insurance coverage. However, in 2017, the Centers for Medicare and Medicaid Services issued a decision memorandum to support health insurance coverage of 12 weeks of supervised treadmill exercise for patients with walking impairment due to PAD. Recent evidence also supports home-based walking exercise to improve walking performance in people with PAD. Effective home-exercise programs incorporate behavioral change interventions such as a remote coach, goal setting, and self-monitoring. Supervised treadmill exercise programs preferentially improve treadmill walking performance, whereas home-based walking exercise programs preferentially improve corridor walking, such as the 6-minute walk test. Clinical trial evidence also supports arm or leg ergometry exercise to improve walking endurance in people with PAD. Treadmill walking exercise appears superior to resistance training alone for improving walking endurance. Supervised treadmill exercise significantly improves treadmill walking performance in people with PAD by approximately 180 meters compared with no exercise. Recent evidence suggests that home-based exercise is also effective and preferentially improves over-ground walking performance, such as the 6-minute walk test. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Lee, S. M.; Bennett, B. S.; Hargens, A. R.; Watenpaugh, D. E.; Ballard, R. E.; Murthy, G.; Ford, S. R.; Fortney, S. M.
1997-01-01
Adaptation to bed rest or space flight is accompanied by an impaired ability to exercise in an upright position. We hypothesized that a daily, 30-min bout of intense, interval exercise in upright posture or supine against lower body negative pressure (LBNP) would maintain upright exercise heart rate and respiratory responses after bed rest. Twenty-four men (31 +/- 3 yr) underwent 5 d of 6 degree head-down tilt: eight performed no exercise (CON), eight performed upright treadmill exercise (UPex), and eight performed supine treadmill exercise against LBNP at -51.3 +/- 0.4 mm Hg (LBNPex). Submaximal treadmill exercise responses (56, 74, and 85% of VO2peak) were measured pre- and post-bed rest. In CON, submaximal heart rate, respiratory exchange ratio, and ventilation were significantly greater (P < or = 0.05) after bed rest. In UPex and LBNPex, submaximal exercise responses were similar pre- and post-bed rest. Our results indicate that a daily 30-min bout of intense, interval upright exercise training or supine exercise training against LBNP is sufficient to maintain upright exercise responses after 5 d of bed rest. These results may have important implications for the development of exercise countermeasures during space flight.
Bean, Jonathan F; Bailey, Allison; Kiely, Dan K; Leveille, Suzanne G
2007-08-15
To examine attitudes toward exercise among a vulnerable aged population characterized by low socioeconomic status, poor functional status and lack of available therapeutic exercise resources. This cross-sectional survey among public low-income housing residents (n = 94), aged > 70 years utilizes these assessments: Physician-based Assessment & Counseling for Exercise (PACE) scale, exercise self-efficacy score, Short Physical Performance Battery (SPPB), Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) scales. Readiness to exercise differed significantly (p < 0.001) across physical performance levels, and ADL and IADL groups. Exercise self-efficacy also differed significantly (p < 0.001) across performance levels. The highest performance level (score 7 - 12) had a significantly (p < 0.05) higher self-efficacy score (x=7.0+/-2.8) than the medium performance level (score 4 - 6) (x=5.3+/-2.8) and the lowest performance level (0 - 3) (x=4.3+/-2.5) groups. Exercise self-efficacy also differed significantly (p < 0.001) across ADL and IADL groups. However, interest in home-based or class-based exercise participation was high among all groups. More than 70% of subjects reported interest with no significant difference noted among groups. Attitudes toward exercise are significantly associated with observed physical function and self-reported disability among vulnerable older adults living in public low-income housing.
Travier, Noémie; Velthuis, Miranda J; Steins Bisschop, Charlotte N; van den Buijs, Bram; Monninkhof, Evelyn M; Backx, Frank; Los, Maartje; Erdkamp, Frans; Bloemendal, Haiko J; Rodenhuis, Carla; de Roos, Marnix A J; Verhaar, Marlies; ten Bokkel Huinink, Daan; van der Wall, Elsken; Peeters, Petra H M; May, Anne M
2015-06-08
Exercise started shortly after breast cancer diagnosis might prevent or diminish fatigue complaints. The Physical Activity during Cancer Treatment (PACT) study was designed to primarily examine the effects of an 18-week exercise intervention, offered in the daily clinical practice setting and starting within 6 weeks after diagnosis, on preventing an increase in fatigue. This multi-centre controlled trial randomly assigned 204 breast cancer patients to usual care (n = 102) or supervised aerobic and resistance exercise (n = 102). By design, all patients received chemotherapy between baseline and 18 weeks. Fatigue (i.e., primary outcome at 18 weeks), quality of life, anxiety, depression, and physical fitness were measured at 18 and 36 weeks. Intention-to-treat mixed linear model analyses showed that physical fatigue increased significantly less during cancer treatment in the intervention group compared to control (mean between-group differences at 18 weeks: -1.3; 95 % CI -2.5 to -0.1; effect size -0.30). Results for general fatigue were comparable but did not reach statistical significance (-1.0, 95%CI -2.1; 0.1; effect size -0.23). At 18 weeks, submaximal cardiorespiratory fitness and several muscle strength tests (leg extension and flexion) were significantly higher in the intervention group compared to control, whereas peak oxygen uptake did not differ between groups. At 36 weeks these differences were no longer statistically significant. Quality of life outcomes favoured the exercise group but were not significantly different between groups. A supervised 18-week exercise programme offered early in routine care during adjuvant breast cancer treatment showed positive effects on physical fatigue, submaximal cardiorespiratory fitness, and muscle strength. Exercise early during treatment of breast cancer can be recommended. At 36 weeks, these effects were no longer statistically significant. This might have been caused by the control participants' high physical activity levels during follow-up. Current Controlled Trials ISRCTN43801571, Dutch Trial Register NTR2138. Trial registered on December 9th, 2009.
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.
Zheng, Xinyan; Hasegawa, Hiroshi
2016-10-01
Dopamine (DA) has been widely investigated for its potential role in determining exercise performance. It was originally thought that DA's ergogenic effect was by mediating psychological responses. Recently, some studies have also suggested that DA may regulate physiological responses, such as thermoregulation. Hyperthermia has been demonstrated as an important limiting factor during endurance exercise. DA is prominent in the thermoregulatory centre, and changes in DA concentration have been shown to affect core temperature regulation during exercise. Some studies have proposed that DA or DA/noradrenaline (NA) reuptake inhibitors can improve exercise performance, despite hyperthermia during exercise in the heat. DA/NA reuptake inhibitors also increase catecholamine release in the thermoregulatory centre. Intracerebroventricularly injected DA has been shown to improve exercise performance through inhibiting hyperthermia-induced fatigue, even at normal ambient temperatures. Further, caffeine has been reported to increase DA release in the thermoregulatory centre and improves endurance exercise performance despite increased core body temperature. Taken together, DA has been shown to have ergogenic effects and increase heat storage and hyperthermia tolerance. The mechanisms underlying these effects seem to involve limiting/overriding the inhibitory signals from the central nervous system that result in cessation of exercise due to hyperthermia.
Goo, Young-Mi; Kim, Tae-Ho; Lim, Jin-Yong
2016-03-01
[Purpose] The purpose of the present study is to examine the effects of abductor hallucis and gluteus maximus strengthening exercises on pronated feet. [Subjects and Methods] The present study was conducted with 18 adults without no history of surgery on the foot or ankle. One group performed both gluteus maximus strengthening exercises and abductor hallucis strengthening exercises, while the other group performed only abductor hallucis strengthening exercises five times per week for four weeks. [Results] The group that performed both gluteus maximus and abductor hallucis strengthening exercises showed smaller values in the height of navicular drop than the group that performed only abductor hallucis strengthening exercises. The muscle activity of the gluteus maximus and the vastus medialis increased during heel-strike in the group that added gluteus maximus exercises, and the muscle activity of the abductor hallucis significantly increased in both groups. [Conclusion] Given the results of the present study, it can be suggested that strengthening the gluteus maximus while also performing exercises to correct the pronated foot is an effective method for achieving normal gait.
Effects of Performance Versus Game-Based Mobile Applications on Response to Exercise.
Gillman, Arielle S; Bryan, Angela D
2016-02-01
Given the popularity of mobile applications (apps) designed to increase exercise participation, it is important to understand their effects on psychological predictors of exercise behavior. This study tested a performance feedback-based app compared to a game-based app to examine their effects on aspects of immediate response to an exercise bout. Twenty-eight participants completed a 30-min treadmill run while using one of two randomly assigned mobile running apps: Nike + Running, a performance-monitoring app which theoretically induces an associative, goal-driven state, or Zombies Run!, an app which turns the experience of running into a virtual reality game, theoretically inducing dissociation from primary exercise goals. The two conditions did not differ on primary motivational state outcomes; however, participants reported more associative attentional focus in the performance-monitoring app condition compared to more dissociative focus in the game-based app condition. Game-based and performance-tracking running apps may not have differential effects on goal motivation during exercise. However, game-based apps may help recreational exercisers dissociate from exercise more readily. Increasing the enjoyment of an exercise bout through the development of new and innovative mobile technologies is an important avenue for future research.
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.
A single bout of resistance exercise can enhance episodic memory performance.
Weinberg, Lisa; Hasni, Anita; Shinohara, Minoru; Duarte, Audrey
2014-11-01
Acute aerobic exercise can be beneficial to episodic memory. This benefit may occur because exercise produces a similar physiological response as physical stressors. When administered during consolidation, acute stress, both physical and psychological, consistently enhances episodic memory, particularly memory for emotional materials. Here we investigated whether a single bout of resistance exercise performed during consolidation can produce episodic memory benefits 48 h later. We used a one-leg knee extension/flexion task for the resistance exercise. To assess the physiological response to the exercise, we measured salivary alpha amylase (a biomarker of central norepinephrine), heart rate, and blood pressure. To test emotional episodic memory, we used a remember-know recognition memory paradigm with equal numbers of positive, negative, and neutral IAPS images as stimuli. The group that performed the exercise, the active group, had higher overall recognition accuracy than the group that did not exercise, the passive group. We found a robust effect of valence across groups, with better performance on emotional items as compared to neutral items and no difference between positive and negative items. This effect changed based on the physiological response to the exercise. Within the active group, participants with a high physiological response to the exercise were impaired for neutral items as compared to participants with a low physiological response to the exercise. Our results demonstrate that a single bout of resistance exercise performed during consolidation can enhance episodic memory and that the effect of valence on memory depends on the physiological response to the exercise. Copyright © 2014 Elsevier B.V. All rights reserved.
Impact of polyphenol antioxidants on cycling performance and cardiovascular function.
Trinity, Joel D; Pahnke, Matthew D; Trombold, Justin R; Coyle, Edward F
2014-03-24
This investigation sought to determine if supplementation with polyphenol antioxidant (PA) improves exercise performance in the heat (31.5 °C, 55% RH) by altering the cardiovascular and thermoregulatory responses to exercise. Twelve endurance trained athletes ingested PA or placebo (PLAC) for 7 days. Consecutive days of exercise testing were performed at the end of the supplementation periods. Cardiovascular and thermoregulatory measures were made during exercise. Performance, as measured by a 10 min time trial (TT) following 50 min of moderate intensity cycling, was not different between treatments (PLAC: 292 ± 33 W and PA: 279 ± 38 W, p = 0.12). Gross efficiency, blood lactate, maximal neuromuscular power, and ratings of perceived exertion were also not different between treatments. Similarly, performance on the second day of testing, as assessed by time to fatigue at maximal oxygen consumption, was not different between treatments (PLAC; 377 ± 117 s vs. PA; 364 ± 128 s, p = 0.61). Cardiovascular and thermoregulatory responses to exercise were not different between treatments on either day of exercise testing. Polyphenol antioxidant supplementation had no impact on exercise performance and did not alter the cardiovascular or thermoregulatory responses to exercise in the heat.
Muscle damage and adaptation after the second bout of eccentric exercise of the knee extensors.
Hassan, E S
2014-10-01
This study examined the muscles ability to adapt to eccentric exercise by the changes in serum myoglobin (Mb), creatine kinase (CK) activity and muscle soreness. The study involved 54 healthy young men from the 23± 2yr age group. These were distributed as subjects for three types of experiments with 18 men in each. Subjects performed 300 maximal eccentric exercises. In experiment I, after performing the first bout of exercise, they were split into three subgroups to perform the second bout after a period of 4, 6, and 8 weeks (WK), respectively. In experiment II, performed the second exercise after a period of 2, 3, and 5 wk, respectively. In experiment III, they performed four exercise bouts spaced 1 wk apart. in experiment II a significant (P<0.05) decrease in muscle soreness, serum Mb and CK was found on exercise bout 2. In experiment III, serum CK, Mb and muscle soreness responses were highest following bout 1. It was concluded that performance of a single exercise bout had a prophylactic effect on muscle soreness and serum protein responses that lasts approximately 2 wk, with the greatest adaptation occurring after one bout.
Gong, Wontae
2015-01-01
[Purpose] The present study sought to investigate the influence on static and dynamic lumbar stability of bridge exercise accompanied by an abdominal drawing-in maneuver (ADIM) performed on an uneven support surface. [Subjects] A total of 30 participants were divided into an experimental group (15 participants) and a control group (15 participants). [Methods] The experimental group performed bridge exercise on an unstable surface, whereas the control group performed bridge exercise on a stable surface. The respective bridge exercises were performed for 30 minutes, 3 times per week, for 6 weeks. The static lumbar stability (SLS) and dynamic lumbar stability (DLS) of both the experimental group and the control group were measured using a pressure biofeedback unit. [Results] In the comparison of the initial and final results of the experimental and control groups, only the SLS and DLS of the experimental group were found to be statistically significant. [Conclusion] The results of the present study show that when using bridge exercise to improve SLS and DLS, performing the bridge exercise accompanied by ADIM on an uneven surface is more effective than performing the exercise on a stable surface.
Middelkamp, Jan; van Rooijen, Maaike; Wolfhagen, Peter; Steenbergen, Bert
2017-01-01
The transtheoretical model of behavior change (TTM) is often used to understand changes in health-related behavior, like exercise. Exercise behavior in fitness clubs is an understudied topic, but preliminary studies showed low frequencies and large numbers of drop-out. An initial 12-week self-efficacy intervention reported significant effects on exercise behavior. The objective of this follow up study is testing effects on exercise behavior over 52 weeks and the long-term relationships of all TTM constructs. In total 122 participants (Mage 42.02 yr.; SD 12.29; 67% females) were recruited and randomly assigned to group 1 (control), group 2 (self-set activities) and group 3 (self-set goals coaching). All participants were monitored 52-weeks. Measurements at baseline, 4, 8, 12, 26 and 52 weeks, using validated scales for stages of change, self-efficacy, decisional balance and processes of change. Exercise behavior and drop-outs were registered. An ANOVA revealed that group 3 significantly (p < 0.05) differed in exercise sessions from group 1 and 2 during the 12 weeks. A chi-square test indicated significant differences for continuing exercising after the intervention: 7 of group 1; 6 of group 2; 19 of group 3. In total 5 demonstrated regular exercise behavior at 26 weeks, and 3 at 52 weeks. Self-efficacy, decisional balance, and processes of change showed limited long-term changes over the later stages of change. At all measurements, participants reported more pros than cons and used more behavioral than cognitive processes. Exercise behavior of members in fitness clubs demonstrated dramatic developments in 52 weeks. The frequencies of sessions were so low that health effects will be minimal. The integrative character of the TTM appears to be weak; the data indicated limited relationships. More research is needed to understand exercise behavior and define optimal strategies to increase exercise attendance and decrease drop-outs in the long term. Key points Approximately 151 million individuals exercise in 187.000 fitness clubs worldwide, mainly for health benefits. The transtheoretical model of behavior change is often used to understand changes in health-related behavior, like exercise, but was never applied to this understudied population. An initial 12-week self-efficacy intervention reported significant effects on (increased) exercise behavior. The effects of this intervention were diminished at 26 and 52 weeks, with respectively only five and three participants maintaining regular exercise behavior in fitness clubs. The integrative character of the TTM in this population appears to be weak; the data indicated limited relationships. PMID:28630568
Applying theory of planned behavior to predict exercise maintenance in sarcopenic elderly.
Ahmad, Mohamad Hasnan; Shahar, Suzana; Teng, Nur Islami Mohd Fahmi; Manaf, Zahara Abdul; Sakian, Noor Ibrahim Mohd; Omar, Baharudin
2014-01-01
This study aimed to determine the factors associated with exercise behavior based on the theory of planned behavior (TPB) among the sarcopenic elderly people in Cheras, Kuala Lumpur. A total of 65 subjects with mean ages of 67.5±5.2 (men) and 66.1±5.1 (women) years participated in this study. Subjects were divided into two groups: 1) exercise group (n=34; 25 men, nine women); and 2) the control group (n=31; 22 men, nine women). Structural equation modeling, based on TPB components, was applied to determine specific factors that most contribute to and predict actual behavior toward exercise. Based on the TPB's model, attitude (β=0.60) and perceived behavioral control (β=0.24) were the major predictors of intention to exercise among men at the baseline. Among women, the subjective norm (β=0.82) was the major predictor of intention to perform the exercise at the baseline. After 12 weeks, attitude (men's, β=0.68; women's, β=0.24) and subjective norm (men's, β=0.12; women's, β=0.87) were the predictors of the intention to perform the exercise. "Feels healthier with exercise" was the specific factor to improve the intention to perform and to maintain exercise behavior in men (β=0.36) and women (β=0.49). "Not motivated to perform exercise" was the main barrier among men's intention to exercise. The intention to perform the exercise was able to predict actual behavior regarding exercise at the baseline and at 12 weeks of an intervention program. As a conclusion, TPB is a useful model to determine and to predict maintenance of exercise in the sarcopenic elderly.
Exercise Performance Measurement with Smartphone Embedded Sensor for Well-Being Management
Liu, Chung-Tse; Chan, Chia-Tai
2016-01-01
Regular physical activity reduces the risk of many diseases and improves physical and mental health. However, physical inactivity is widespread globally. Improving physical activity levels is a global concern in well-being management. Exercise performance measurement systems have the potential to improve physical activity by providing feedback and motivation to users. We propose an exercise performance measurement system for well-being management that is based on the accumulated activity effective index (AAEI) and incorporates a smartphone-embedded sensor. The proposed system generates a numeric index that is based on users’ exercise performance: their level of physical activity and number of days spent exercising. The AAEI presents a clear number that can serve as a useful feedback and goal-setting tool. We implemented the exercise performance measurement system by using a smartphone and conducted experiments to assess the feasibility of the system and investigated the user experience. We recruited 17 participants for validating the feasibility of the measurement system and a total of 35 participants for investigating the user experience. The exercise performance measurement system showed an overall precision of 88% in activity level estimation. Users provided positive feedback about their experience with the exercise performance measurement system. The proposed system is feasible and has a positive effective on well-being management. PMID:27727188
Exercise Performance Measurement with Smartphone Embedded Sensor for Well-Being Management.
Liu, Chung-Tse; Chan, Chia-Tai
2016-10-11
Regular physical activity reduces the risk of many diseases and improves physical and mental health. However, physical inactivity is widespread globally. Improving physical activity levels is a global concern in well-being management. Exercise performance measurement systems have the potential to improve physical activity by providing feedback and motivation to users. We propose an exercise performance measurement system for well-being management that is based on the accumulated activity effective index (AAEI) and incorporates a smartphone-embedded sensor. The proposed system generates a numeric index that is based on users' exercise performance: their level of physical activity and number of days spent exercising. The AAEI presents a clear number that can serve as a useful feedback and goal-setting tool. We implemented the exercise performance measurement system by using a smartphone and conducted experiments to assess the feasibility of the system and investigated the user experience. We recruited 17 participants for validating the feasibility of the measurement system and a total of 35 participants for investigating the user experience. The exercise performance measurement system showed an overall precision of 88% in activity level estimation. Users provided positive feedback about their experience with the exercise performance measurement system. The proposed system is feasible and has a positive effective on well-being management.
Ahmed Hamada, Hamada; Hussein Draz, Amira; Koura, Ghada Mohamed; Saab, Ibtissam M.
2017-01-01
[Purpose] This study was carried out to investigate the carryover effect of hip and knee exercises program on functional performance (single legged hop test as functional performance test and Kujala score for functional activities). [Subjects and Methods] Thirty patients with patellofemoral pain syndrome were randomly assigned into two equal groups. Group (A) consisted of 15 patients undergoing hip strengthening exercises for four weeks then measuring all variables followed by additional four weeks of knee exercises program then measuring all variables again. Group (B): consisted of 15 patients undergoing knee exercises program for four weeks then measuring all variables followed by additional four weeks of hip strengthening exercises then measuring all variables. Functional abilities and knee muscles performance were assessed using Kujala questionnaire and single legged hop test respectively pre and after the completion of the first 4 weeks then after 8 weeks for both groups. [Results] Significantly increase in Kujala questionnaire in group A compared with group B was observed. While, there were significant increase in single legged hop performance test in group B compared with group A. [Conclusion] Starting with hip exercises improve the performance of subjects more than functional activities while starting with knee exercises improve the functional activities of subjects more than performance. PMID:28878459
Ahmed Hamada, Hamada; Hussein Draz, Amira; Koura, Ghada Mohamed; Saab, Ibtissam M
2017-08-01
[Purpose] This study was carried out to investigate the carryover effect of hip and knee exercises program on functional performance (single legged hop test as functional performance test and Kujala score for functional activities). [Subjects and Methods] Thirty patients with patellofemoral pain syndrome were randomly assigned into two equal groups. Group (A) consisted of 15 patients undergoing hip strengthening exercises for four weeks then measuring all variables followed by additional four weeks of knee exercises program then measuring all variables again. Group (B): consisted of 15 patients undergoing knee exercises program for four weeks then measuring all variables followed by additional four weeks of hip strengthening exercises then measuring all variables. Functional abilities and knee muscles performance were assessed using Kujala questionnaire and single legged hop test respectively pre and after the completion of the first 4 weeks then after 8 weeks for both groups. [Results] Significantly increase in Kujala questionnaire in group A compared with group B was observed. While, there were significant increase in single legged hop performance test in group B compared with group A. [Conclusion] Starting with hip exercises improve the performance of subjects more than functional activities while starting with knee exercises improve the functional activities of subjects more than performance.
Córdova, C; Silva, V C; Moraes, C F; Simões, H G; Nóbrega, O T
2009-05-01
The objective of the present study was to compare the effect of acute exercise performed at different intensities in relation to the anaerobic threshold (AT) on abilities requiring control of executive functions or alertness in physically active elderly females. Forty-eight physically active elderly females (63.8 +/- 4.6 years old) were assigned to one of four groups by drawing lots: control group without exercise or trial groups with exercise performed at 60, 90, or 110% of AT (watts) and submitted to 5 cognitive tests before and after exercise. Following cognitive pretesting, an incremental cycle ergometer test was conducted to determine AT using a fixed blood lactate concentration of 3.5 mmol/L as cutoff. Acute exercise executed at 90% of AT resulted in significant (P < 0.05, ANOVA) improvement in the performance of executive functions when compared to control in 3 of 5 tests (verbal fluency, Tower of Hanoi test (number of movements), and Trail Making test B). Exercising at 60% of AT did not improve results of any tests for executive functions, whereas exercise executed at 110% of AT only improved the performance in one of these tests (verbal fluency) compared to control. Women from all trial groups exhibited a remarkable reduction in the Simple Response Time (alertness) test (P = 0.001). Thus, physical exercise performed close to AT is more effective to improve cognitive processing of older women even if conducted acutely, and using a customized exercise prescription based on the anaerobic threshold should optimize the beneficial effects.
Tucker, R
2009-06-01
During self-paced exercise, the exercise work rate is regulated by the brain based on the integration of numerous signals from various physiological systems. It has been proposed that the brain regulates the degree of muscle activation and thus exercise intensity specifically to prevent harmful physiological disturbances. It is presently proposed how the rating of perceived exertion (RPE) is generated as a result of the numerous afferent signals during exercise and serves as a mediator of any subsequent alterations in skeletal muscle activation levels and exercise intensity. A conceptual model for how the RPE mediates feedforward, anticipatory regulation of exercise performance is proposed, and this model is applied to previously described research studies of exercise in various conditions, including heat, hypoxia and reduced energy substrate availability. Finally, the application of this model to recent novel studies that altered pacing strategies and performance is described utilising an RPE clamp design, central nervous system drugs and the provision of inaccurate duration or distance feedback to exercising athletes.
Exercise training improves heart rate variability after methamphetamine dependency.
Dolezal, Brett Andrew; Chudzynski, Joy; Dickerson, Daniel; Mooney, Larissa; Rawson, Richard A; Garfinkel, Alan; Cooper, Christopher B
2014-06-01
Heart rate variability (HRV) reflects a healthy autonomic nervous system and is increased with physical training. Methamphetamine dependence (MD) causes autonomic dysfunction and diminished HRV. We compared recently abstinent methamphetamine-dependent participants with age-matched, drug-free controls (DF) and also investigated whether HRV can be improved with exercise training in the methamphetamine-dependent participants. In 50 participants (MD = 28; DF = 22), resting heart rate (HR; R-R intervals) was recorded over 5 min while seated using a monitor affixed to a chest strap. Previously reported time domain (SDNN, RMSSD, pNN50) and frequency domain (LFnu, HFnu, LF/HF) parameters of HRV were calculated with customized software. MD were randomized to thrice-weekly exercise training (ME = 14) or equal attention without training (MC = 14) over 8 wk. Groups were compared using paired and unpaired t-tests. Statistical significance was set at P ≤ 0.05. Participant characteristics were matched between groups (mean ± SD): age = 33 ± 6 yr; body mass = 82.7 ± 12 kg, body mass index = 26.8 ± 4.1 kg·min. Compared with DF, the MD group had significantly higher resting HR (P < 0.05), LFnu, and LF/HF (P < 0.001) as well as lower SDNN, RMSSD, pNN50, and HFnu (all P < 0.001). At randomization, HRV indices were similar between ME and MC groups. However, after training, the ME group significantly (all P < 0.001) increased SDNN (+14.7 ± 2.0 ms, +34%), RMSSD (+19.6 ± 4.2 ms, +63%), pNN50 (+22.6% ± 2.7%, +173%), HFnu (+14.2 ± 1.9, +60%), and decreased HR (-5.2 ± 1.1 bpm, -7%), LFnu (-9.6 ± 1.5, -16%), and LF/HF (-0.7 ± 0.3, -19%). These measures did not change from baseline in the MC group. HRV, based on several conventional indices, was diminished in recently abstinent, methamphetamine-dependent individuals. Moreover, physical training yielded a marked increase in HRV, representing increased vagal modulation or improved autonomic balance.
NASA Technical Reports Server (NTRS)
Schneider, V. S.; Hulley, S. B.; Donaldson, C. L.; Vogel, J. M.; Rosen, S. N.; Hantman, D. A.; Lockwood, D. R.; Seid, D.; Hyatt, K. H.; Jacobson, L. B.
1974-01-01
The phenomenon of calcium loss during bed rest was found to be analogous to the loss of bone material which occurs in the hypogravic environment of space flight. Ways of preventing this occurrence are investigated. A group of healthy adult males underwent 24-30 weeks of continuous bed rest. Some of them were given an exercise program designed to resemble normal ambulatory activity; another subgroup was fed supplemental potassium phosphate. The results from a 12-week period of treatment were compared with those untreated bed rest periods. The potassium phosphate supplements prevented the hypercalciuria of bed rest, but fecal calcium tended to increase. The exercise program did not diminish the negative calcium balance. Neither treatment affected the heavy loss of mineral from the calcaneus. Several additional studies are developed to examine the problem further.
Oberste, Max; Hartig, Philipp; Bloch, Wilhelm; Elsner, Benjamin; Predel, Hans-Georg; Ernst, Bernhard; Zimmer, Philipp
2017-01-01
Introduction: Many studies report improvements in cognitive performance following acute endurance exercise compared to control group treatment. These cognitive benefits are interpreted as a result of a physiological response to exercise. However, it was also hypothesized that expectation-driven placebo effects account for these positive effects. The purpose of this study was to investigate the differences between expectations for cognitive benefits toward acute endurance exercise and multiple control group treatments. Methods: Healthy individuals (N = 247, 24.26 ± 3.88 years) were randomized to eight different groups watching videos of a moderate, a vigorous exercise treatment or one control group treatment (waiting, reading, video-watching, stretching, myofascial release workout, and very light exercise). Then, they were introduced to three commonly used cognitive test procedures in acute exercise-cognition research (Stroop-test, Trail-Making-test, Free-recall-task). Participants rated the effect they would expect on their performance in those tasks, if they had received the treatment shortly before the task, on an 11-point Likert scale. Results: No significantly different expectations for cognitive benefits toward acute moderate exercise and control group treatments could be revealed. Participants expected significantly worse performance following vigorous exercise compared to following waiting and stretching for all cognitive tests. Significantly worse performance after vigorous exercise compared to after very light exercise was expected for Stroop and Free-recall. For Free-recall, participants expected worse performance after vigorous exercise compared to myofascial release training as well. Conclusion: Our results indicate that expectation-driven placebo effects are unlikely to cause the reported greater cognitive improvements following acute moderate and vigorous endurance exercise compared to following common control group treatments. PMID:29276483
Gross, M Melissa; Wright, Mary C; Anderson, Olivia S
2017-09-01
Research on the benefits of visual learning has relied primarily on lecture-based pedagogy, but the potential benefits of combining active learning strategies with visual and verbal materials on learning anatomy has not yet been explored. In this study, the differential effects of text-based and image-based active learning exercises on examination performance were investigated in a functional anatomy course. Each class session was punctuated with an average of 12 text-based and image-based active learning exercises. Participation data from 231 students were compared with their examination performance on 262 questions associated with the in-class exercises. Students also rated the helpfulness and difficulty of the in-class exercises on a survey. Participation in the active learning exercises was positively correlated with examination performance (r = 0.63, P < 0.001). When controlling for other key demographics (gender, underrepresented minority status) and prior grade point average, participation in the image-based exercises was significantly correlated with performance on examination questions associated with image-based exercises (P < 0.001) and text-based exercises (P < 0.01), while participation in text-based exercises was not. Additionally, students reported that the active learning exercises were helpful for seeing images of key ideas (94%) and clarifying key course concepts (80%), and that the image-based exercises were significantly less demanding, less hard and required less effort than text-based exercises (P < 0.05). The findings confirm the positive effect of using images and active learning strategies on student learning, and suggest that integrating them may be especially beneficial for learning anatomy. Anat Sci Educ 10: 444-455. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.
Defining Exercise Performance Metrics for Flight Hardware Development
NASA Technical Reports Server (NTRS)
Beyene, Nahon M.
2004-01-01
The space industry has prevailed over numerous design challenges in the spirit of exploration. Manned space flight entails creating products for use by humans and the Johnson Space Center has pioneered this effort as NASA's center for manned space flight. NASA Astronauts use a suite of flight exercise hardware to maintain strength for extravehicular activities and to minimize losses in muscle mass and bone mineral density. With a cycle ergometer, treadmill, and the Resistive Exercise Device available on the International Space Station (ISS), the Space Medicine community aspires to reproduce physical loading schemes that match exercise performance in Earth s gravity. The resistive exercise device presents the greatest challenge with the duty of accommodating 20 different exercises and many variations on the core set of exercises. This paper presents a methodology for capturing engineering parameters that can quantify proper resistive exercise performance techniques. For each specified exercise, the method provides engineering parameters on hand spacing, foot spacing, and positions of the point of load application at the starting point, midpoint, and end point of the exercise. As humans vary in height and fitness levels, the methodology presents values as ranges. In addition, this method shows engineers the proper load application regions on the human body. The methodology applies to resistive exercise in general and is in use for the current development of a Resistive Exercise Device. Exercise hardware systems must remain available for use and conducive to proper exercise performance as a contributor to mission success. The astronauts depend on exercise hardware to support extended stays aboard the ISS. Future plans towards exploration of Mars and beyond acknowledge the necessity of exercise. Continuous improvement in technology and our understanding of human health maintenance in space will allow us to support the exploration of Mars and the future of space exploration.
Patients' perspectives on aerobic exercise early after stroke.
Prout, Erik C; Mansfield, Avril; McIlroy, William E; Brooks, Dina
2017-04-01
To describe patient perspectives of aerobic exercise during inpatient stroke rehabilitation, including their self-efficacy and beliefs towards exercise, as well as their perceptions of barriers. A survey was conducted at three Canadian rehabilitation centres to evaluate individuals' (N = 33) self-efficacy and outcome expectations for exercise. In addition, patient perceptions of other people recovering from stroke, social support, and aerobic exercise as part of rehabilitation were assessed. Thirty-two people completed the survey. Of these, 97% were willing to participate in aerobic exercise 5.9 ± 8.8 days after admission to inpatient rehabilitation. While outcome expectations for exercise were high, participants reported lower self-efficacy for exercise. Patients reported barriers related to the ability to perform exercise (other health problems (i.e., arthritis), not being able to follow instructions and physical impairments) more often than safety concerns (fear of falling). The lack of support from a spouse and family were commonly identified, as was a lack of information on how to perform aerobic exercise. Patients with stroke are willing to participate in aerobic exercise within a week after admission to inpatient rehabilitation. However, they perceive a lack of ability to perform aerobic exercise, social support from family and information as barriers. Implications for rehabilitation Aerobic exercise is recognized as part of comprehensive stroke rehabilitation. There is a need to better understand patient perspectives to develop and implement more effective interventions early after stroke. Patients lack confidence in their ability to overcome barriers early after stroke. Patients are concerned with their ability to perform exercise, fall risk, lack of support from a spouse and family, and limited information on aerobic exercise. There is a need to reinforce education with practical experience in structured aerobic exercise programs that show patients and caregivers how to manage disability and complex health needs.
Acute exercise and motor memory consolidation: Does exercise type play a role?
Thomas, R; Flindtgaard, M; Skriver, K; Geertsen, S S; Christiansen, L; Korsgaard Johnsen, L; Busk, D V P; Bojsen-Møller, E; Madsen, M J; Ritz, C; Roig, M; Lundbye-Jensen, J
2017-11-01
A single bout of high-intensity exercise can augment off-line gains in skills acquired during motor practice. It is currently unknown if the type of physical exercise influences the effect on motor skill consolidation. This study investigated the effect of three types of high-intensity exercise following visuomotor skill acquisition on the retention of motor memory in 40 young (25.3 ±3.6 years), able-bodied male participants randomly assigned to one of four groups either performing strength training (STR), circuit training (CT), indoor hockey (HOC) or rest (CON). Retention tests of the motor skill were performed 1 (R1h) and 24 h (R1d) post acquisition. For all exercise groups, mean motor performance scores decreased at R1h compared to post acquisition (POST) level; STR (P = 0.018), CT (P = 0.02), HOC (P = 0.014) and performance scores decreased for CT compared to CON (P = 0.049). Mean performance scores increased from POST to R1d for all exercise groups; STR (P = 0.010), CT (P = 0.020), HOC (P = 0.007) while performance scores for CON decreased (P = 0.043). Changes in motor performance were thus greater for STR (P = 0.006), CT (P < 0.001) and HOC (P < 0.001) compared to CON from POST to R1d. The results demonstrate that high-intensity, acute exercise can lead to a decrease in motor performance assessed shortly after motor skill practice (R1h), but enhances offline effects promoting long-term retention (R1d). Given that different exercise modalities produced similar positive off-line effects on motor memory, we conclude that exercise-induced effects beneficial to consolidation appear to depend primarily on the physiological stimulus rather than type of exercise and movements employed. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
The Effects of Physical Exercise and Cognitive Training on Memory and Neurotrophic Factors.
Heisz, Jennifer J; Clark, Ilana B; Bonin, Katija; Paolucci, Emily M; Michalski, Bernadeta; Becker, Suzanna; Fahnestock, Margaret
2017-11-01
This study examined the combined effect of physical exercise and cognitive training on memory and neurotrophic factors in healthy, young adults. Ninety-five participants completed 6 weeks of exercise training, combined exercise and cognitive training, or no training (control). Both the exercise and combined training groups improved performance on a high-interference memory task, whereas the control group did not. In contrast, neither training group improved on general recognition performance, suggesting that exercise training selectively increases high-interference memory that may be linked to hippocampal function. Individuals who experienced greater fitness improvements from the exercise training (i.e., high responders to exercise) also had greater increases in the serum neurotrophic factors brain-derived neurotrophic factor and insulin-like growth factor-1. These high responders to exercise also had better high-interference memory performance as a result of the combined exercise and cognitive training compared with exercise alone, suggesting that potential synergistic effects might depend on the availability of neurotrophic factors. These findings are especially important, as memory benefits accrued from a relatively short intervention in high-functioning young adults.
If I Could Just Stop Loving You: Anti-Love Biotechnology and the Ethics of a Chemical Breakup
Earp, Brian D.; Wudarczyk, Olga A.; Sandberg, Anders; Savulescu, Julian
2013-01-01
“Love hurts”—as the saying goes—and a certain amount of pain and difficulty in intimate relationships is unavoidable. Sometimes it may even be beneficial, since adversity can lead to personal growth, self-discovery, and a range of other components of a life well-lived. But other times, love can be downright dangerous. It may bind a spouse to her domestic abuser, draw an unscrupulous adult toward sexual involvement with a child, put someone under the insidious spell of a cult leader, and even inspire jealousy-fueled homicide. How might these perilous devotions be diminished? The ancients thought that treatments such as phlebotomy, exercise, or bloodletting could “cure” an individual of love. But modern neuroscience and emerging developments in psychopharmacology open up a range of possible interventions that might actually work. These developments raise profound moral questions about the potential uses—and misuses—of such anti-love biotechnology. In this article, we describe a number of prospective love-diminishing interventions, and offer a preliminary ethical framework for dealing with them responsibly should they arise. PMID:24161170
If I could just stop loving you: anti-love biotechnology and the ethics of a chemical breakup.
Earp, Brian D; Wudarczyk, Olga A; Sandberg, Anders; Savulescu, Julian
2013-01-01
"Love hurts"-as the saying goes-and a certain amount of pain and difficulty in intimate relationships is unavoidable. Sometimes it may even be beneficial, since adversity can lead to personal growth, self-discovery, and a range of other components of a life well-lived. But other times, love can be downright dangerous. It may bind a spouse to her domestic abuser, draw an unscrupulous adult toward sexual involvement with a child, put someone under the insidious spell of a cult leader, and even inspire jealousy-fueled homicide. How might these perilous devotions be diminished? The ancients thought that treatments such as phlebotomy, exercise, or bloodletting could "cure" an individual of love. But modern neuroscience and emerging developments in psychopharmacology open up a range of possible interventions that might actually work. These developments raise profound moral questions about the potential uses-and misuses-of such anti-love biotechnology. In this article, we describe a number of prospective love-diminishing interventions, and offer a preliminary ethical framework for dealing with them responsibly should they arise.
Sweat production during global heating and during isometric exercise in people with diabetes.
Petrofsky, Jerrold Scott; Lee, Scott; Patterson, Chris; Cole, Melissa; Stewart, Brian
2005-11-01
While sweat production in response to heat is impaired in people with diabetes, sweat production has not been examined during isometric exercise. Eight subjects with type 2 diabetes and 9 control subjects exerted a fatiguing isometric contraction of the handgrip muscles at a tension of 40% of the maximum voluntary strength (MVC) after exposure to a 32 deg C environment for 30 min. compared to 10 controls and 10 subjects with diabetes exposed to a 39 deg C environment. Sweat was impaired to all areas of the body during heat exposure in patients with diabetes under both environmental conditions. For example, on the chest, the average sweat rates after exposure to the 32 deg environment was 259.2 +/- 55.2 nanoliters/min in control subjects and 198.3 +/- 46.2 nanoliters/min for subjects with diabetes. Compared to the 32 deg C environment, control subjects increased sweat in all 4 areas proportionally more than subjects with diabetes. Sudomotor rhythm was present in sweat in control subjects at a rate of repetition of 11 and 50 seconds but almost absent in subjects with diabetes. During exercise, sweat rates slowly increased from the beginning to the end of the exercise. But the head of the subjects with diabetes showed hypersweating while the other areas showed diminished sweating compared to control subjects. Thus some of the impairment in sweating may be due to central mechanisms associated with heat sensitivity or in the hypothalamus and not to the sweat glands themselves.
Smoking, weight loss intention and obesity-promoting behaviors in college students.
Carroll, Shawna L; Lee, Rebecca E; Kaur, Harsohena; Harris, Kari J; Strother, Myra L; Huang, Terry T-K
2006-08-01
To examine whether college smoking was associated with trying to lose weight and other weight-related behaviors. We surveyed 300 students at the University of Kansas about smoking (ever, current, and amount), weight loss intention (y/n), weight-related attitudes, and eating and exercise behavior. Weight, height, and body fat were measured. About half the students (49%) self-identified as having ever smoked while 53 (17.6%) self-identified as current smokers. After controlling for sex, age, and ethnicity, ever smoking was not related to weight loss intention but was associated with greater pressure to maintain a healthy weight (p = 0.05), and having engaged in mild exercise on more days in the previous year (p = 0.05). Compared to nonsmokers, current smokers ate more at restaurants serving high calorie foods (p < 0.05) and ate more frequently in front of the TV (p < 0.01). Amount smoked was related to diminished use of exercise facilities (p = 0.03) and more frequent eating at restaurants serving high calorie foods (p < 0.05) and in front of the TV (p = 0.01). Current smoking among college students was related to weight loss intention. Despite wanting to lose weight, current smoking was concomitant with obesity-promoting behaviors such as eating higher calorie foods and eating in front of the TV. College-based interventions to prevent smoking initiation or promote smoking cessation should include a focus on healthy eating, exercise and healthful ways to lose or maintain weight.
Kanazawa, H; Okamoto, T; Hirata, K; Yoshikawa, J
2000-10-01
Angiotensin converting enzyme (ACE) plays an important role in the pathogenesis of pulmonary hypertension. In this study we determined whether the deletion (D)/insertion (I) polymorphism in the ACE gene may be associated with pulmonary hypertension evoked by exercise challenge in patients with chronic obstructive pulmonary disease (COPD). ACE genotypes were determined in 19 patients with COPD. All patients underwent right heart catheterization followed by a constant-load exercise test while breathing room air or oxygen. Subgroups were created of seven patients with the II genotype, six with the ID genotype, and six with the DD genotype who were well-matched with respect to age, blood gas data at rest or after exercise, baseline lung function, results of incremental exercise testing, and hemodynamic data at rest. The mean pulmonary arterial pressure (Ppa) and pulmonary vascular resistance (Rpv) at rest in the three subgrpoups did not differ significantly during breathing of either room air or oxygen. However, the Ppa after exercise challenge in patients with the DD genotype (55.7 +/- 4.9 mm Hg [mean +/- SD]) was significantly higher than in patients with the II genotype (42.6 +/- 7.1 mm Hg, p = 0.008). The Rpv after exercise in patients with the DD genotype was also significantly higher than in patients with the ID and II genotypes. During breathing of oxygen to diminish acute hypoxic pulmonary vasoconstriction, the Ppa in patients with the DD genotype (52.3 +/- 3.1 mm Hg) was higher than in patients with the ID genotype (40.5 +/- 5.9 mm Hg, p = 0.0049) or the II genotype (37.7 +/- 5.9 mm Hg, p = 0.0027). In addition, the Rpv in patients with the DD genotype was higher than in patients with the ID and II genotypes. These results suggest that D-I polymorphism in the ACE gene may be associated with pulmonary hypertension evoked by exercise challenge in patients with COPD. However, the number of patients in this study was very small for a genetic association study, and our results should be examined in larger studies.
Orbital Fitness: An Overview of Space Shuttle Cardiopulmonary Exercise Physiology Findings
NASA Technical Reports Server (NTRS)
Moore, Alan D.
2011-01-01
Limited observations regarding the cardiopulmonary responses to aerobic exercise had been conducted during short-duration spaceflight before the Space Shuttle program. This presentation focuses on the findings regarding changes observed in the cardiopulmonary exercise responses during and following Shuttle flights. During flight, maximum oxygen uptake (VO2max) remained unchanged as did the maximum work rate achievable during cycle exercise testing conducted during the last full flight day. Immediately following flight, the ubiquitous finding, confirmed by investigations conducted during the Spacelab Life Sciences missions 1 and 2 and by NASA Detailed Supplemental Objective studies, indicated that VO2max was reduced; however, the reduction in VO2max was transient and returned to preflight levels within 7 days following return. Studies regarding the influence of aerobic exercise countermeasures performed during flight on postflight performance were mostly limited to the examination of the heart rate (HR) response to submaximal exercise testing on landing day. These studies revealed that exercise HR was elevated in individuals who performed little to no exercise during their missions as compared to individuals who performed regular exercise. In addition, astronauts who performed little to no aerobic exercise during flight demonstrated an increased HR and lowered pulse pressure response to the standard stand test on landing day, indicating a decrease in orthostatic function in these individuals. With regard to exercise modality, four devices were examined during the Shuttle era: two treadmills, a cycle ergometer, and a rowing device. Although there were limited investigations regarding the use of these devices for exercise training aboard the Shuttle, there was no clear consensus reached regarding which proved to be a "superior" device. Each device had a unique operational or physiologic limitation associated with its use. In conclusion, exercise research conducted during the Shuttle Program demonstrated that attenuation of postflight deconditioning was possible through use of exercise countermeasures and the Shuttle served as a test bed for equipment destined for use on the International Space Station. Learning Objective: Overview of the Space Shuttle Program research results related to aerobic capacity and performance, including what was learned from research and effectiveness of exercise countermeasures.
International Society of Sports Nutrition Position Stand: protein and exercise.
Jäger, Ralf; Kerksick, Chad M; Campbell, Bill I; Cribb, Paul J; Wells, Shawn D; Skwiat, Tim M; Purpura, Martin; Ziegenfuss, Tim N; Ferrando, Arny A; Arent, Shawn M; Smith-Ryan, Abbie E; Stout, Jeffrey R; Arciero, Paul J; Ormsbee, Michael J; Taylor, Lem W; Wilborn, Colin D; Kalman, Doug S; Kreider, Richard B; Willoughby, Darryn S; Hoffman, Jay R; Krzykowski, Jamie L; Antonio, Jose
2017-01-01
The International Society of Sports Nutrition (ISSN) provides an objective and critical review related to the intake of protein for healthy, exercising individuals. Based on the current available literature, the position of the Society is as follows:An acute exercise stimulus, particularly resistance exercise, and protein ingestion both stimulate muscle protein synthesis (MPS) and are synergistic when protein consumption occurs before or after resistance exercise.For building muscle mass and for maintaining muscle mass through a positive muscle protein balance, an overall daily protein intake in the range of 1.4-2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals, a value that falls in line within the Acceptable Macronutrient Distribution Range published by the Institute of Medicine for protein.Higher protein intakes (2.3-3.1 g/kg/d) may be needed to maximize the retention of lean body mass in resistance-trained subjects during hypocaloric periods.There is novel evidence that suggests higher protein intakes (>3.0 g/kg/d) may have positive effects on body composition in resistance-trained individuals (i.e., promote loss of fat mass).Recommendations regarding the optimal protein intake per serving for athletes to maximize MPS are mixed and are dependent upon age and recent resistance exercise stimuli. General recommendations are 0.25 g of a high-quality protein per kg of body weight, or an absolute dose of 20-40 g.Acute protein doses should strive to contain 700-3000 mg of leucine and/or a higher relative leucine content, in addition to a balanced array of the essential amino acids (EAAs).These protein doses should ideally be evenly distributed, every 3-4 h, across the day.The optimal time period during which to ingest protein is likely a matter of individual tolerance, since benefits are derived from pre- or post-workout ingestion; however, the anabolic effect of exercise is long-lasting (at least 24 h), but likely diminishes with increasing time post-exercise.While it is possible for physically active individuals to obtain their daily protein requirements through the consumption of whole foods, supplementation is a practical way of ensuring intake of adequate protein quality and quantity, while minimizing caloric intake, particularly for athletes who typically complete high volumes of training. Rapidly digested proteins that contain high proportions of essential amino acids (EAAs) and adequate leucine, are most effective in stimulating MPS. Different types and quality of protein can affect amino acid bioavailability following protein supplementation. Athletes should consider focusing on whole food sources of protein that contain all of the EAAs (i.e., it is the EAAs that are required to stimulate MPS). Endurance athletes should focus on achieving adequate carbohydrate intake to promote optimal performance; the addition of protein may help to offset muscle damage and promote recovery. Pre-sleep casein protein intake (30-40 g) provides increases in overnight MPS and metabolic rate without influencing lipolysis.
Bernhardt, Vipa; Mitchell, Gordon S.; Lee, Won Y.; Babb, Tony G.
2016-01-01
Background The ventilatory response to exercise can be transiently adjusted in response to environmentally (e.g., breathing apparatus) or physiologically altered conditions (e.g., respiratory disease), maintaining constant relative arterial PCO2 regulation from rest to exercise (Mitchell and Babb, 2006); this augmentation is called short-term modulation (STM) of the exercise ventilatory response. Obesity and/or obstructive sleep apnea could affect the exercise ventilatory response and the capacity for STM due to chronically increased mechanical and/or ventilatory loads on the respiratory system, and/or recurrent (chronic) intermittent hypoxia experienced during sleep. We hypothesized that: 1) the exercise ventilatory response is augmented in obese OSA patients compared with obese non-OSA adults, and 2) the capacity for STM with added dead space is diminished in obese OSA patients. Methods Nine obese adults with OSA (age: 39 ± 6 yr, BMI: 40 ± 5 kg/m2, AHI: 25 ± 24 events/hr [range 6–73], mean ± SD) and 8 obese adults without OSA (age: 38 ± 10 yr, BMI: 37 ± 6 kg/m2, AHI: 1 ± 2) completed three, 20-min bouts of constant-load submaximal cycling exercise (8 min rest, 6 min at 10 and 30 W) with or without added external dead space (200 or 400 ml; 20 min rest between bouts). Steady-state measurements were made of ventilation (V̇E), oxygen consumption (V̇O2), carbon dioxide production (V̇CO2), and end-tidal PCO2 (PETCO2). The exercise ventilatory response was defined as the slope of the V̇E-V̇CO2 relationship (ΔV̇E/ΔV̇CO2). Results In control (i.e. no added dead space), the exercise ventilatory response was not significantly different between non-OSA and OSA groups (ΔV̇E/ΔV̇CO2 slope: 30.5 ± 4.2 vs 30.5 ± 3.8, p > 0.05); PETCO2 regulation from rest to exercise did not differ between groups (p > 0.05). In trials with added external dead space, ΔV̇E/ΔV̇CO2 increased with increased dead space (p < 0.05) and the PETCO2 change from rest to exercise remained small (<2 mmHg) in both groups, demonstrating STM. There were no significant differences between groups. Conclusions Contrary to our hypotheses: 1) the exercise ventilatory response is not increased in obese OSA patients compared with obese non-OSA adults, and 2) the capacity for STM with added dead space is preserved in obese OSA and non-OSA adults. PMID:27840272
Educational Innovations in Academic Medicine and Environmental Trends
Irby, David M; Wilkerson, LuAnn
2003-01-01
Fifteen educational innovations in academic medicine are described in relation to 5 environmental trends. The first trend, demands for increased clinical productivity, has diminished the learning environment, necessitating new organizational structures to support teaching, such as academies of medical educators, mission-based management, and faculty development. The second trend is multidisciplinary approaches to science and education. This is stimulating the growth of multidisciplinary curricular design and oversight along with integrated curricular structures. Third, the science of learning advocates the use of case-based, active learning methods; learning communities such as societies and colleges; and instructional technology. Fourth, shifting views of health and disease are encouraging the addition of new content in the curriculum. In response, theme committees are weaving content across the curriculum, new courses are being inserted into curricula, and community-based education is providing learning experiences outside of academic medical centers. Fifth, calls for accountability are leading to new forms of performance assessment using objective structured clinical exams, clinical examination exercises, simulators, and comprehensive assessment programs. These innovations are transforming medical education. PMID:12795736
Hypo-egoic self-regulation: exercising self-control by diminishing the influence of the self.
Leary, Mark R; Adams, Claire E; Tate, Eleanor B
2006-12-01
Theory and research dealing with self-regulation have focused primarily on instances of self-regulation that involve high levels of self-reflection and effortful self-control. However, intentionally trying to control one's behavior sometimes reduces the likelihood of achieving one's goals. This article examines the process of hypo-egoic self-regulation in which people relinquish deliberate, conscious control over their own behavior so that they will respond more naturally, spontaneously, or automatically. An examination of spontaneously occurring hypo-egoic states (such as flow, deindividuation, and transcendence) suggests that hypo-egoic states are characterized by lowered self-awareness and/or an increase in concrete and present-focused self-thoughts. In light of this, people may intentionally foster hypo-egoism via two pathways-(a) taking steps to reduce the proportion of time that they are self-aware (such as repeating a behavior until it is automatic or practicing meditation) or (b) increasing the concreteness of their self-thoughts (such as inducing a concrete mindset or practicing mindfulness). In this way, people may deliberately choose to regulate hypo-egoically when effortful control might be detrimental to their performance.
Biomedical results of the Skylab Program.
Michel, E L; Johnston, R S; Dietlein, L F
1976-01-01
Skylab, the fourth in a logical sequence of USA manned space flight projects following Mercury, Gemini and Apollo, presented life scientists with their first opportunity for an in-depth study of man's response to the space environment. Extensive medical investigations were undertaken to increase our understanding of man's adaptation to the space environment and his readaptation to gravity upon return to earth. The flight durations of the three Skylab missions were progressively increased from 28 days to 59 days and, finally, 84 days. The results of these investigations of the various body systems clearly demonstrated that man can adapt to zero gravity and perform useful work during long-duration space flight. However, definite changes (some unexpected) in the vestibular, cardiovascular, musculo-skeletal, renal and electrolyte areas were documented. The most significant were: the occurrence of space motion sickness early in the missions; diminished orthostatic tolerance, both in-flight and post-flight; moderate losses of calcium, phosphorus and nitrogen; and decreased tolerance for exercise post-flight. The mechanisms responsible for these physiological responses must be understood and, if necessary, effective countermeasures developed before man can endure unlimited exposure to space flight.
Kinetic Analysis of Horizontal Plyometric Exercise Intensity.
Kossow, Andrew J; Ebben, William P
2018-05-01
Kossow, AJ, DeChiara, TG, Neahous, SM, and Ebben, WP. Kinetic analysis of horizontal plyometric exercise intensity. J Strength Cond Res 32(5): 1222-1229, 2018-Plyometric exercises are frequently performed as part of a strength and conditioning program. Most studies assessed the kinetics of plyometric exercises primarily performed in the vertical plane. The purpose of this study was to evaluate the multiplanar kinetic characteristics of a variety of plyometric exercises, which have a significant horizontal component. This study also sought to assess sex differences in the intensity progression of these exercises. Ten men and 10 women served as subjects. The subjects performed a variety of plyometric exercises including the double-leg hop, standing long jump, single-leg standing long jump, bounding, skipping, power skipping, cone hops, and 45.72-cm hurdle hops. Subjects also performed the countermovement jump for comparison. All plyometric exercises were evaluated using a force platform. Dependent variables included the landing rate of force development and landing ground reaction forces for each exercise in the vertical, frontal, and sagittal planes. A 2-way mixed analysis of variance with repeated-measures for plyometric exercise type demonstrated main effects for exercise type for all dependent variables (p ≤ 0.001). There was no significant interaction between plyometric exercise type and sex for any of the variable assessed. Bonferroni-adjusted pairwise comparisons identified a number of differences between the plyometric exercises for the dependent variables assessed (p ≤ 0.05). These findings should be used to guide practitioners in the progression of plyometric exercise intensity, and thus program design, for those who require significant horizontal power in their sport.
Fitzgerald, Diarmaid; Foody, John; Kelly, Dan; Ward, Tomas; Markham, Charles; McDonald, John; Caulfield, Brian
2007-01-01
This paper describes the design and development of a computer game for instructing an athlete through a series of prescribed rehabilitation exercises. In an attempt to prevent or treat musculoskeletal type injuries along with trying to improve physical performance, athletes are prescribed exercise programmes by appropriately trained specialists. Typically athletes are shown how to perform each exercise in the clinic following examination but they often have no way of knowing if their technique is correct while they are performing their home exercise programme. We describe a system that allows an automatic audit of this activity. Our system utilises ten inertial motion tracking sensors incorporated in a wearable body suit which allows a bluetooth connection from a root hub to a laptop/computer. Using our specifically designed software programme, the athlete can be instructed and analysed as he/she performs the individually tailored exercise programme and a log is recorded of the time and performance level of each exercise completed. We describe a case study that illustrates how a clinician can at a later date review the athletes progress and subsequently alter the exercise programme as they see fit.
Muscle damage and repeated bout effect following blood flow restricted exercise.
Sieljacks, Peter; Matzon, Andreas; Wernbom, Mathias; Ringgaard, Steffen; Vissing, Kristian; Overgaard, Kristian
2016-03-01
Blood-flow restricted resistance exercise training (BFRE) is suggested to be effective in rehabilitation training, but more knowledge is required about its potential muscle damaging effects. Therefore, we investigated muscle-damaging effects of BFRE performed to failure and possible protective effects of previous bouts of BFRE or maximal eccentric exercise (ECC). Seventeen healthy young men were allocated into two groups completing two exercise bouts separated by 14 days. One group performed BFRE in both exercise bouts (BB). The other group performed ECC in the first and BFRE in the second bout. BFRE was performed to failure. Indicators of muscle damage were evaluated before and after exercise. The first bout in the BB group led to decrements in maximum isometric torque, and increases in muscle soreness, muscle water retention, and serum muscle protein concentrations after exercise. These changes were comparable in magnitude and time course to what was observed after first bout ECC. An attenuated response was observed in the repeated exercise bout in both groups. We conclude that unaccustomed single-bout BFRE performed to failure induces significant muscle damage. Additionally, both ECC and BFRE can precondition against muscle damage induced by a subsequent bout of BFRE.
Exercise Increases 24-h Fat Oxidation Only When It Is Performed Before Breakfast
Iwayama, Kaito; Kurihara, Reiko; Nabekura, Yoshiharu; Kawabuchi, Ryosuke; Park, Insung; Kobayashi, Masashi; Ogata, Hitomi; Kayaba, Momoko; Satoh, Makoto; Tokuyama, Kumpei
2015-01-01
Background As part of the growing lifestyle diversity in modern society, there is wide variation in the time of day individuals choose to exercise. Recent surveys in the US and Japan have reported that on weekdays, more people exercise in the evening, with fewer individuals exercising in the morning or afternoon. Exercise performed in the post-prandial state has little effect on accumulated fat oxidation over 24 h (24-h fat oxidation) when energy intake is matched to energy expenditure (energy-balanced condition). The present study explored the possibility that exercise increases 24-h fat oxidation only when performed in a post-absorptive state, i.e. before breakfast. Methods Indirect calorimetry using a metabolic chamber was performed in 10 young, non-obese men over 24 h. Subjects remained sedentary (control) or performed 60-min exercise before breakfast (morning), after lunch (afternoon), or after dinner (evening) at 50% of VO2max. All trials were designed to be energy balanced over 24 h. Time course of energy and substrate balance relative to the start of calorimetry were estimated from the differences between input (meal consumption) and output (oxidation). Findings Fat oxidation over 24 h was increased only when exercise was performed before breakfast (control, 456 ± 61; morning, 717 ± 64; afternoon, 446 ± 57; and evening, 432 ± 44 kcal/day). Fat oxidation over 24 h was negatively correlated with the magnitude of the transient deficit in energy and carbohydrate. Interpretation Under energy-balanced conditions, 24-h fat oxidation was increased by exercise only when performed before breakfast. Transient carbohydrate deficits, i.e., glycogen depletion, observed after morning exercise may have contributed to increased 24-h fat oxidation. PMID:26844280
Tanaka, Daichi; Tsukamoto, Hayato; Suga, Tadashi; Takenaka, Saki; Hamaoka, Takafumi; Hashimoto, Takeshi; Isaka, Tadao
2018-05-26
Acute aerobic exercise improves inhibitory control (IC). This improvement is often associated with increases in perceived exertion during exercise. However, listening to music during aerobic exercise mitigates an exercise-induced increase in perceived exertion. Thus, it is hypothesized that such effects of music may interfere with exercise-induced improvements in IC. To test this hypothesis, we examined the effect of music on post-exercise IC improvements that were induced by moderate-intensity exercise. Fifteen healthy young men performed cycle ergometer exercise with music or non-music. The exercise was performed using a moderate-intensity of 60% of VO 2 peak for 30 min. The music condition was performed while listening to self-selected music. The non-music condition involved no music. To evaluate IC, the Stroop task was administered before exercise, immediately after exercise, and during the 30-min post-exercise recovery period. The rate of perceived exertion immediately before moderate-intensity exercise completed was significantly lower in music condition than in non-music condition. The IC significantly improved immediately after exercise and during the post-exercise recovery period compared to before exercise in both music and non-music conditions. The post-exercise IC improvements did not significantly differ between the two conditions. These findings indicate that self-selected music-induced mitigation of the increase in perceived exertion during moderate-intensity exercise dose not interfere with exercise-induced improvements in IC. Therefore, we suggest that listening to music may be a beneficial strategy in mitigating the increase in perceived exertion during aerobic exercise without decreasing the positive effects on IC. Copyright © 2018 Elsevier Inc. All rights reserved.
Barbosa, Luis F; Denadai, Benedito S; Greco, Camila C
2016-01-01
Slow component of oxygen uptake (VO 2 SC) kinetics and maximal oxygen uptake (VO 2 max) attainment seem to influence endurance performance during constant-work rate exercise (CWR) performed within the severe intensity domain. In this study, it was hypothesized that delaying the attainment of VO 2 max by reducing the rates at which VO 2 increases with time (VO 2 SC kinetics) would improve the endurance performance during severe-intensity intermittent exercise performed with different work:recovery duration and recovery type in active individuals. After the estimation of the parameters of the VO 2 SC kinetics during CWR exercise, 18 males were divided into two groups (Passive and Active recovery) and performed at different days, two intermittent exercises to exhaustion (at 95% IVO 2 max, with work: recovery ratio of 2:1) with the duration of the repetitions calculated from the onset of the exercise to the beginning of the VO 2 SC (Short) or to the half duration of the VO 2 SC (Long). The active recovery was performed at 50% IVO 2 max. The endurance performance during intermittent exercises for the Passive (Short = 1523 ± 411; Long = 984 ± 260 s) and Active (Short = 902 ± 239; Long = 886 ± 254 s) groups was improved compared with CWR condition (Passive = 540 ± 116; Active = 489 ± 84 s). For Passive group, the endurance performance was significantly higher for Short than Long condition. However, no significant difference between Short and Long conditions was found for Active group. Additionally, the endurance performance during Short condition was higher for Passive than Active group. The VO 2 SC kinetics was significantly increased for CWR (Passive = 0.16 ± 0.04; Active = 0.16 ± 0.04 L.min -2 ) compared with Short (Passive = 0.01 ± 0.01; Active = 0.03 ± 0.04 L.min -2 ) and Long (Passive = 0.02 ± 0.01; Active = 0.01 ± 0.01 L.min -2 ) intermittent exercise conditions. No significant difference was found among the intermittent exercises. It can be concluded that the endurance performance is negatively influenced by active recovery only during shorter high-intensity intermittent exercise. Moreover, the improvement in endurance performance seems not be explained by differences in the VO 2 SC kinetics, since its values were similar among all intermittent exercise conditions.
Sossdorf, Maik; Fischer, Jacqueline; Meyer, Stefan; Dahlke, Katja; Wissuwa, Bianka; Seidel, Carolin; Schrepper, Andrea; Bockmeyer, Clemens L; Lupp, Amelie; Neugebauer, Sophie; Schmerler, Diana; Rödel, Jürgen; Claus, Ralf A; Otto, Gordon P
2013-10-01
High physical activity levels are associated with wide-ranging health benefits, disease prevention, and longevity. In the present study, we examined the impact of regular physical exercise on the severity of organ injury and survival probability, as well as characteristics of the systemic immune and metabolic response during severe polymicrobial sepsis. Animal study. University laboratory. Male C57BL/6N mice. Mice were trained for 6 weeks by treadmill and voluntary wheel running or housed normally. Polymicrobial sepsis in mice was induced by injection of fecal slurry. Subsequently, mice were randomized into the following groups: healthy controls, 6 hours postsepsis, and 24 hours postsepsis. Blood and organ samples were collected and investigated by measuring clinical chemistry variables, cytokines, plasma metabolites, and bacterial clearance. Organ morphology and damage were characterized by histological staining. Physical exercise improved survival and the ability of bacterial clearance in blood and organs. The release of pro- and anti-inflammatory cytokines, including interleukin-6 and interleukin-10, was diminished in trained compared to untrained mice during sepsis. The sepsis-associated acute kidney tubular damage was less pronounced in pretrained animals. By metabolic profiling and regression analysis, we detected lysophosphatidylcholine 14:0, tryptophan, as well as pimelylcarnitine linked with levels of neutrophil gelatinase-associated lipocalin representing acute tubular injury (corrected R=0.910; p<0.001). We identified plasma lysophosphatidylcholine 16:0, lysophosphatidylcholine 17:0, and lysophosphatidylcholine 18:0 as significant metabolites discriminating between trained and untrained mice during sepsis. Regular physical exercise reduces sepsis-associated acute kidney injury and death. As a specific mechanism of exercise-induced adaptation, we identified various lysophosphatidylcholines that might function as surrogate for improved outcome in sepsis.
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.
Engberg, Elina; Liira, Helena; Kukkonen-Harjula, Katriina; From, Svetlana; Kautiainen, Hannu; Pitkälä, Kaisu; Tikkanen, Heikki O
2017-06-01
Few community-based lifestyle interventions have examined subjective well-being. We examined the effects of health counseling and exercise training on self-rated health (SRH), self-rated well-being (SRW) and depressive symptoms in middle-aged men at increased risk for cardiovascular disease (CVD) in a randomized controlled trial. Men (N.=168) with at least two CVD risk factors engaging in leisure-time physical activity less than three times/week were randomized into: A) a group receiving single-session health counseling; B) a group receiving single-session health counseling and three months of weekly structured group exercise training; or C) a control group. We assessed SRH and SRW using visual analogue scales and depressive symptoms using a brief depression screener (the Patient Health Questionnaire-2, PHQ-2). Generalized estimating equation (GEE) models showed that, after 3 and 12 months, SRH (P=0.024) and SRW (P=0.014) improved across all groups. We found no differences between the groups (group by time effect, P=0.44 and P=0.80). The proportion of men with PHQ-2 scores ≥3 (positive depression screen) decreased in groups A (from 27% to 13%) and B (from 34% to 18%), but increased among controls (from 26% to 31%) (group by time effect, P=0.078). We found improvements in SRH and SRW, with a diminishing proportion of men screening positive for depression one year after a single health counseling session and a three-month exercise-training program. We detected, however, no statistically significant differences when comparing men who received health counseling or health counseling combined with exercise training to controls.
Effects of voluntary exercise on structure and function of cortical microvasculature.
Dorr, Adrienne; Thomason, Lynsie Am; Koletar, Margaret M; Joo, Illsung L; Steinman, Joe; Cahill, Lindsay S; Sled, John G; Stefanovic, Bojana
2017-03-01
Aerobic activity has been shown highly beneficial to brain health, yet much uncertainty still surrounds the effects of exercise on the functioning of cerebral microvasculature. This study used two-photon fluorescence microscopy to examine cerebral hemodynamic alterations as well as accompanying geometric changes in the cortical microvascular network following five weeks of voluntary exercise in transgenic mice endogenously expressing tdTomato in vascular endothelial cells to allow visualization of microvessels irrespective of their perfusion levels. We found a diminished microvascular response to a hypercapnic challenge (10% FiCO 2 ) in running mice when compared to that in nonrunning controls despite commensurate increases in transcutaneous CO 2 tension. The flow increase to hypercapnia in runners was 70% lower than that in nonrunners (p = 0.0070) and the runners' arteriolar red blood cell speed changed by only half the amount seen in nonrunners (p = 0.0085). No changes were seen in resting hemodynamics or in the systemic physiological parameters measured. Although a few unperfused new vessels were observed on visual inspection, running did not produce significant morphological differences in the microvascular morphometric parameters, quantified following semiautomated tracking of the microvascular networks. We propose that voluntary running led to increased cortical microvascular efficiency and desensitization to CO 2 elevation.
BIOCHEMICAL ANALYSIS AND BONE REMODELING IN RESPONSE TO OOPHORECTOMY AND AQUATIC TRAINING
SOUZA, HELENA RIBEIRO; GIROL, ANA PAULA; SCHIAVETO, ADRIANA PAULA SANCHEZ; GEROMEL, MAIRTO ROBERIS; IYOMASA, MELINA MIZUSAKI; ARRUDA, MAURÍCIO FERRAZ DE
2016-01-01
ABSTRACT Objective: To investigate whether swimming could prevent bone loss and could be indicated to assist in treatment of osteoporosis. Methods: Female rats were divided into 4 groups (n=6), two of them were oophorectomized. Animals from two groups, one oophorectomized and another not oophorectomized, underwent aquatic training for eight weeks. After training, the animals were sacrificed and their blood was collected for calcium and alkaline phosphatase serum dosage; the femur was removed and subjected to radiological and histological densitometry analysis to assess bone loss and osteoclast counting on femoral head and neck. Results: Increase in serum calcium was not observed. There was an increasing activity of alkaline phosphatase in the oophorectomized groups. The radiographs suggest that there was a greater bone mass density in the trained groups. Concerning histology, the trained groups had better tissue structural organization than the sedentary groups. In the oophorectomized and sedentary group, higher presence of osteoclasts was observed a. Conclusion: Exercise and oophorectomy did not promote changes in serum calcium levels. The decrease of sex steroids caused by oophorectomy was responsible for severe bone loss, but swimming exercise was able to reduce this loss. Oophorectomy promoted the proliferation of osteoclasts and the exercise proved to be able to diminish it. Level of Evidence I, Experimental Study. PMID:28149187
Mukaimoto, Takahiro; Ohno, Makoto
2012-01-01
The purpose of this study was to examine oxygen consumption (VO(2)) during and after a single bout of low-intensity resistance exercise with slow movement. Eleven healthy men performed the following three types of circuit resistance exercise on separate days: (1) low-intensity resistance exercise with slow movement: 50% of one-repetition maximum (1-RM) and 4 s each of lifting and lowering phases; (2) high-intensity resistance exercise with normal movement: 80% of 1-RM and 1 s each of lifting and lowering phases; and (3) low-intensity resistance exercise with normal movement: 50% of 1-RM and 1 s each of lifting and lowering phases. These three resistance exercise trials were performed for three sets in a circuit pattern with four exercises, and the participants performed each set until exhaustion. Oxygen consumption was monitored continuously during exercise and for 180 min after exercise. Average VO(2) throughout the exercise session was significantly higher with high- and low-intensity resistance exercise with normal movement than with low-intensity resistance exercise with slow movement (P < 0.05); however, total VO(2) was significantly greater in low-intensity resistance exercise with slow movement than in the other trials. In contrast, there were no significant differences in the total excess post-exercise oxygen consumption among the three exercise trials. The results of this study suggest that low-intensity resistance exercise with slow movement induces much greater energy expenditure than resistance exercise with normal movement of high or low intensity, and is followed by the same total excess post-exercise oxygen consumption for 180 min after exercise.
Exercise, cognition, and the adolescent brain.
Herting, Megan M; Chu, Xiaofang
2017-12-01
Few adolescents engage in the recommended levels of physical activity, and daily exercise levels tend to drastically decrease throughout adolescence. Beyond physical health benefits, regular exercise may also have important implications for the teenage brain and cognitive and academic capabilities. This narrative review examines how physical activity and aerobic exercise relate to school performance, cognition, and brain structure and function. A number of studies have found that habitual exercise and physical activity are associated with academic performance, cognitive function, brain structure, and brain activity in adolescents. We also discuss how additional intervention studies that examine a wide range of neurological and cognitive outcomes are necessary, as well as characterizing the type, frequency, and dose of exercise and identifying individual differences that contribute to how exercise may benefit the teen brain. Routine exercise relates to adolescent brain structure and function as well as cognitive performance. Together, these studies suggest that physical activity and aerobic exercise may be important factors for optimal adolescent brain development. © 2017 Wiley Periodicals, Inc.
Spildooren, Joke; Speetjens, Ite; Abrahams, Johan; Feys, Peter; Timmermans, Annick
2018-04-28
Motivation towards an exercise program is higher in a small group setting in comparison to individual therapy. Due to attentional problems, group exercises are difficult for people with Alzheimer disease (AD). This study evaluates the feasibility of a music-supported video-based group exercise program in older adults suffering from AD. Five participants with moderate AD were recruited from a nursing home. A progressive physical exercise program using a video-based training with musical accompaniment was performed and digitally recorded to investigate the adherence and performed accuracy of the exercises. The overall participation during the exercises was 84.1%. The quality of the performance was for all exercises above the cut-off scores. A music-supported video-based group exercise program is feasible in persons with AD. The participants were motivated and the expectations towards the program increased over time. Music seemed an important factor for attention in participants with AD.
Effects of Pilates Exercise on Salivary Secretory Immunoglobulin A Levels in Older Women.
Hwang, Yoonyoung; Park, Jonghoon; Lim, Kiwon
2016-07-01
We examined the effects of a Pilates exercise program on the mucosal immune function in older women. The study population comprised 12 older women who were divided into a Pilates group (PG, n = 6) and a control group (CG, n = 6). Saliva samples were obtained from both groups before and after the experimental period for salivary secretory immunoglobulin A level measurement. In addition, acute high-intensity exercises were performed before and after the three-month Pilates exercise program. After three months, salivary flow was significantly higher in the PG than in the CG. After the acute high-intensity exercises were performed following the three-month Pilates exercise program, the salivary flow rate was significantly higher at all time points. The S-IgA secretion rate significantly increased 30 min after acute high-intensity exercise performed following the three-month Pilates exercise program. This study suggests that regular participation in a moderate-intensity Pilates exercise program can increase salivary flow rate and S-IgA secretion in older women.
Cell phone use diminishes self-awareness of the adverse effects of cell phone use on driving.
DOT National Transportation Integrated Search
2017-03-01
Multitasking may diminish the self-awareness of performance that is often essential for self-regulation : and self-knowledge. Participants in an experiment drove on a simulator while talking or not talking on a : cell phone. The errors they made whil...
Hashim, Hairul A; Freddy, Golok; Rosmatunisah, Ali
2012-09-01
The current study was undertaken to examine the associations between self-determination, exercise habit, anxiety, depression, stress, and academic achievement among adolescents aged 13 and 14 years in eastern Malaysia. The sample consisted of 750 secondary school students (mean age = 13.4 years, SD = 0.49). Participants completed self-report measures of exercise behavioral regulation, negative affect, and exercise habit strength. Midyear exam results were used as an indicator of academic performance. Structural equation modeling was used to analyze the data. The results of structural equation modeling revealed a close model fit for the hypothesized model, which indicates that higher levels of self-determination were positively associated with habituated exercise behavior. In turn, exercise habit strength fostered academic achievement and buffered the debilitative effect of stress, depression, and anxiety on student academic performance. The analysis of model invariance revealed a nonsignificant difference between male and female subjects. The findings support the notion that habituated exercise fosters academic performance. In addition, we found that habituated exercise buffers the combined effects of stress, anxiety and depression on academic performance. The finding also supports the roles of self-determination in promoting exercise habituation.
Design and Evaluation of an Interactive Exercise Coaching System for Older Adults: Lessons Learned
Ofli, Ferda; Kurillo, Gregorij; Obdržálek, Štěpán; Bajcsy, Ruzena; Jimison, Holly; Pavel, Misha
2016-01-01
Although the positive effects of exercise on the well-being and quality of independent living for older adults are well-accepted, many elderly individuals lack access to exercise facilities, or the skills and motivation to perform exercise at home. To provide a more engaging environment that promotes physical activity, various fitness applications have been proposed. Many of the available products, however, are geared toward a younger population and are not appropriate or engaging for an older population. To address these issues, we developed an automated interactive exercise coaching system using the Microsoft Kinect. The coaching system guides users through a series of video exercises, tracks and measures their movements, provides real-time feedback, and records their performance over time. Our system consists of exercises to improve balance, flexibility, strength, and endurance, with the aim of reducing fall risk and improving performance of daily activities. In this paper, we report on the development of the exercise system, discuss the results of our recent field pilot study with six independently-living elderly individuals, and highlight the lessons learned relating to the in-home system setup, user tracking, feedback, and exercise performance evaluation. PMID:25594988
Neuromotor control in chronic obstructive pulmonary disease.
Mantilla, Carlos B; Sieck, Gary C
2013-05-01
Neuromotor control of skeletal muscles, including respiratory muscles, is ultimately dependent on the structure and function of the motor units (motoneurons and the muscle fibers they innervate) comprising the muscle. In most muscles, considerable diversity of contractile and fatigue properties exists across motor units, allowing a range of motor behaviors. In diseases such as chronic obstructive pulmonary disease (COPD), there may be disproportional primary (disease related) or secondary effects (related to treatment or other concomitant factors) on the size and contractility of specific muscle fiber types that would influence the relative contribution of different motor units. For example, with COPD there is a disproportionate atrophy of type IIx and/or IIb fibers that comprise more fatigable motor units. Thus fatigue resistance may appear to improve, while overall motor performance (e.g., 6-min walk test) and endurance (e.g., reduced aerobic exercise capacity) are diminished. There are many coexisting factors that might also influence motor performance. For example, in COPD patients, there may be concomitant hypoxia and/or hypercapnia, physical inactivity and unloading of muscles, and corticosteroid treatment, all of which may disproportionately affect specific muscle fiber types, thereby influencing neuromotor control. Future studies should address how plasticity in motor units can be harnessed to mitigate the functional impact of COPD-induced changes.
Shimano, Tomoko; Kraemer, William J; Spiering, Barry A; Volek, Jeff S; Hatfield, Disa L; Silvestre, Ricardo; Vingren, Jakob L; Fragala, Maren S; Maresh, Carl M; Fleck, Steven J; Newton, Robert U; Spreuwenberg, Luuk P B; Häkkinen, Keijo
2006-11-01
Resistance exercise intensity is commonly prescribed as a percent of 1 repetition maximum (1RM). However, the relationship between percent 1RM and the number of repetitions allowed remains poorly studied, especially using free weight exercises. The purpose of this study was to determine the maximal number of repetitions that trained (T) and untrained (UT) men can perform during free weight exercises at various percentages of 1RM. Eight T and 8 UT men were tested for 1RM strength. Then, subjects performed 1 set to failure at 60, 80, and 90% of 1RM in the back squat, bench press, and arm curl in a randomized, balanced design. There was a significant (p < 0.05) intensity x exercise interaction. More repetitions were performed during the back squat than the bench press or arm curl at 60% 1RM for T and UT. At 80 and 90% 1RM, there were significant differences between the back squat and other exercises; however, differences were much less pronounced. No differences in number of repetitions performed at a given exercise intensity were noted between T and UT (except during bench press at 90% 1RM). In conclusion, the number of repetitions performed at a given percent of 1RM is influenced by the amount of muscle mass used during the exercise, as more repetitions can be performed during the back squat than either the bench press or arm curl. Training status of the individual has a minimal impact on the number of repetitions performed at relative exercise intensity.
Marshall, Paul W M; Desai, Imtiaz
2010-06-01
Although there is now some evidence examining the use of a Swiss ball during core stability and resistance exercises, this has commonly been performed using basic or isometric exercises. There is currently no evidence examining more advanced Swiss ball exercises. The purpose of this study was to determine whether or not muscle activity measured during advanced Swiss ball exercises was at an approximate intensity recommended for strength or endurance training in advanced, or novice individuals. After a familiarization session, 14 recreationally active subjects performed 6 different "advanced" Swiss ball exercises in a randomized order. The primary dependent variables in this study were the activity levels collected from anterior deltoid, pectoralis major, rectus abdominis (RA), external obliques, lumbar erector spinae, vastus lateralis (VL), and biceps femoris using surface electromyography. All signals were normalized to maximal voluntary isometric contractions performed before testing for each muscle. The results of this study showed that the Swiss ball roll elicited muscle activity in triceps brachii (72.5+/-32.4%) and VL (83.6+/-44.2%) commensurate with the intensity recommended for strength exercises in advanced trainers. Rectus abdominis activity was greatest during the bridge exercise (61.3+/-28.5%, p
Applying theory of planned behavior to predict exercise maintenance in sarcopenic elderly
Ahmad, Mohamad Hasnan; Shahar, Suzana; Teng, Nur Islami Mohd Fahmi; Manaf, Zahara Abdul; Sakian, Noor Ibrahim Mohd; Omar, Baharudin
2014-01-01
This study aimed to determine the factors associated with exercise behavior based on the theory of planned behavior (TPB) among the sarcopenic elderly people in Cheras, Kuala Lumpur. A total of 65 subjects with mean ages of 67.5±5.2 (men) and 66.1±5.1 (women) years participated in this study. Subjects were divided into two groups: 1) exercise group (n=34; 25 men, nine women); and 2) the control group (n=31; 22 men, nine women). Structural equation modeling, based on TPB components, was applied to determine specific factors that most contribute to and predict actual behavior toward exercise. Based on the TPB’s model, attitude (β=0.60) and perceived behavioral control (β=0.24) were the major predictors of intention to exercise among men at the baseline. Among women, the subjective norm (β=0.82) was the major predictor of intention to perform the exercise at the baseline. After 12 weeks, attitude (men’s, β=0.68; women’s, β=0.24) and subjective norm (men’s, β=0.12; women’s, β=0.87) were the predictors of the intention to perform the exercise. “Feels healthier with exercise” was the specific factor to improve the intention to perform and to maintain exercise behavior in men (β=0.36) and women (β=0.49). “Not motivated to perform exercise” was the main barrier among men’s intention to exercise. The intention to perform the exercise was able to predict actual behavior regarding exercise at the baseline and at 12 weeks of an intervention program. As a conclusion, TPB is a useful model to determine and to predict maintenance of exercise in the sarcopenic elderly. PMID:25258524
Effect of a Cooling Kit on Physiology and Performance Following Exercise in the Heat.
Smith, Cody R; Butts, Cory L; Adams, J D; Tucker, Matthew A; Moyen, Nicole E; Ganio, Matthew S; McDermott, Brendon P
2017-06-12
Exercising in the heat leads to an increase in body temperature that can increase the risk of heat illness or cause detriments in exercise performance. To examine a phase change heat emergency kit (HEK) on thermoregulatory and perceptual responses, and subsequent exercise performance following exercise in the heat. Two randomized crossover trials which consisted of 30 minutes of exercise, 15 minutes of treatment (T 1 ), performance testing (5-10-5 pro-agility test, 1500 m run), and another 15 minutes of treatment (T 2 ) identical to T 1 . Outdoors in the heat (WBGT 31.5 ± 1.8°C, 59.0 ± 5.6% RH). Twenty-six (13 male, 13 female) individuals (20-27 y). Treatment was performed with HEK or without (CON) modality. Gastrointestinal temperature (T GI ), mean skin temperature (T SK ), thirst sensation, and muscle pain. Maximum T GI following exercise and performance was not different between trials (P > 0.05). Cooling rate was faster during T 1 CON (0.053 ± 0.049 °C/min) compared to HEK (0.043 ± 0.032°C/min; P = 0.01). T SK was lower in HEK during T 1 (P < 0.001) and T 2 (P = 0.050). T 2 thirst was lower in CON (P = 0.021). Muscle pain was lower in HEK in T 2 (P = 0.026). Performance was not altered (P > 0.05). HEK improved perception, but did not enhance cooling or performance following exercise in the heat. HEK is, therefore, not recommended to facilitate recovery, treat hyperthermia or improve performance.
Drug abusers have impaired cerebral oxygenation and cognition during exercise
Soares Rachetti, Vanessa; Quirino Alves da Silva, Weslley; Aranha Rego Cabral, Daniel; Gomes da Silva Machado, Daniel; Caldas Costa, Eduardo; Forti, Rodrigo Menezes; Mesquita, Rickson Coelho; Elsangedy, Hassan Mohamed; Hideki Okano, Alexandre; Bodnariuc Fontes, Eduardo
2017-01-01
Background Individuals with Substance Use Disorder (SUD) have lower baseline metabolic activity of the prefrontal cortex (PFC) associated with impairment of cognitive functions in decision-making and inhibitory control. Aerobic exercise has shown to improve PFC function and cognitive performance, however, its effects on SUD individuals remain unclear. Purpose To verify the cognitive performance and oxygenation of the PFC during an incremental exercise in SUD individuals. Methods Fourteen individuals under SUD treatment performed a maximum graded exercise test on a cycle ergometer with continuous measurements of oxygen consumption, PFC oxygenation, and inhibitory control (Stroop test) every two minutes of exercise at different intensities. Fifteen non-SUD individuals performed the same protocol and were used as control group. Results Exercise increased oxyhemoglobin (O2Hb) and total hemoglobin (tHb) by 9% and 7%, respectively. However, when compared to a non-SUD group, this increase was lower at high intensities (p<0.001), and the inhibitory cognitive control was lower at rest and during exercise (p<0.007). In addition, PFC hemodynamics during exercise was inversely correlated with inhibitory cognitive performance (reaction time) (r = -0.62, p = 0.001), and a lower craving perception for the specific abused substance (p = 0.0189) was reported immediately after exercise. Conclusion Despite SUD individuals having their PFC cerebral oxygenation increased during exercise, they presented lower cognition and oxygenation when compared to controls, especially at elevated intensities. These results may reinforce the role of exercise as an adjuvant treatment to improve PFC function and cognitive control in individuals with SUD. PMID:29125875
Erkmen, Nurtekin; Suveren, Sibel; Göktepe, Ahmet Salim
2012-06-01
The objective of the present study was to determine the effects of exercise continued until the anaerobic threshold on balance performance in basketball players. Twelve male basketball players (age = 20.92 ± 2.81 years, body height = 192.72 ± 7.61 cm, body mass = 88.09 ± 8.41 kg, training experience = 7.17 ± 3.10 years) volunteered to participate in this study. A Kinesthetic Ability Trainer (KAT 2000 stabilometer) was used to measure the balance performance. Balance tests consisted of static tests on dominant, nondominant and double leg stance. The Bruce Protocol was performed by means of a treadmill. The exercise protocol was terminated when the subject passed the anaerobic threshold. After the exercise protocol, balance measurements were immediately repeated. Statistical differences between pre and post-exercise for dominant, nondominant and double leg stance were determined by the paired samples t-test according to the results of the test of normality. The post-exercise balance score on the dominant leg was significantly higher than pre-exercise (t = -2.758, p < 0.05). No differences existed between pre- and post-exercise in the balance scores of the nondominant leg after the exercise protocol (t = 0.428, p > 0.05). A significant difference was found between pre and post-exercise balance scores in the double leg stance (t = -2.354, p < 0.05). The main finding of this study was that an incremental exercise continued until the anaerobic threshold decreased balance performance on the dominant leg in basketball players, but did not alter it in the nondominant leg.
Duncan, Michael J; Smith, Mike; Bryant, Elizabeth; Eyre, Emma; Cook, Kathryn; Hankey, Joanne; Tallis, Jason; Clarke, Neil; Jones, Marc V
2016-01-01
The aim of this study was to investigate if the effects of changes in physiological arousal on timing performance can be accurately predicted by the catastrophe model. Eighteen young adults (8 males, 10 females) volunteered to participate in the study following ethical approval. After familiarisation, coincidence anticipation was measured using the Bassin Anticipation Timer under four incremental exercise conditions: Increasing exercise intensity and low cognitive anxiety, increasing exercise intensity and high cognitive anxiety, decreasing exercise intensity and low cognitive anxiety and decreasing exercise intensity and high cognitive anxiety. Incremental exercise was performed on a treadmill at intensities of 30%, 50%, 70% and 90% heart rate reserve (HRR) respectively. Ratings of cognitive anxiety were taken at each intensity using the Mental Readiness Form 3 (MRF3) followed by performance of coincidence anticipation trials at speeds of 3 and 8 mph. Results indicated significant condition × intensity interactions for absolute error (AE; p = .0001) and MRF cognitive anxiety intensity scores (p = .05). Post hoc analysis indicated that there were no statistically significant differences in AE across exercise intensities in low-cognitive anxiety conditions. In high-cognitive anxiety conditions, timing performance AE was significantly poorer and cognitive anxiety higher at 90% HRR, compared to the other exercise intensities. There was no difference in timing responses at 90% HRR during competitive trials, irrespective of whether exercise intensity was increasing or decreasing. This study suggests that anticipation timing performance is negatively affected when physiological arousal and cognitive anxiety are high.
Minett, Geoffrey M.; Duffield, Rob
2013-01-01
Prolonged intermittent-sprint exercise (i.e., team sports) induce disturbances in skeletal muscle structure and function that are associated with reduced contractile function, a cascade of inflammatory responses, perceptual soreness, and a delayed return to optimal physical performance. In this context, recovery from exercise-induced fatigue is traditionally treated from a peripheral viewpoint, with the regeneration of muscle physiology and other peripheral factors the target of recovery strategies. The direction of this research narrative on post-exercise recovery differs to the increasing emphasis on the complex interaction between both central and peripheral factors regulating exercise intensity during exercise performance. Given the role of the central nervous system (CNS) in motor-unit recruitment during exercise, it too may have an integral role in post-exercise recovery. Indeed, this hypothesis is indirectly supported by an apparent disconnect in time-course changes in physiological and biochemical markers resultant from exercise and the ensuing recovery of exercise performance. Equally, improvements in perceptual recovery, even withstanding the physiological state of recovery, may interact with both feed-forward/feed-back mechanisms to influence subsequent efforts. Considering the research interest afforded to recovery methodologies designed to hasten the return of homeostasis within the muscle, the limited focus on contributors to post-exercise recovery from CNS origins is somewhat surprising. Based on this context, the current review aims to outline the potential contributions of the brain to performance recovery after strenuous exercise. PMID:24550837
Bischoff, Adrianne Rahde; Cunha, Fábio da Silva; Dalle Molle, Roberta; Maróstica, Paulo José Cauduro; Silveira, Patrícia Pelufo
2018-02-22
The literature suggests that a fetus will adapt to surrounding adversities by optimizing its use of energy to improve survival, ultimately leading to the programming of the individual's energy intake and expenditure. While recent reviews focused on the fetal programming of energy intake and food preferences, there is also some evidence that fetal adversity is associated with diminished physical activity levels. Therefore, we aimed to review (a) the evidence for an association between being born with intrauterine growth restriction and sedentarism over the life-course and (b) the potential benefits of physical activity over cardiometabolic risk factors for this population. PubMed, Scielo, Scopus and Embase. Most clinical studies that used objective measures found no association between intrauterine growth restriction and physical activity levels, while most studies that used self-reported questionnaires revealed such relationships, particularly leisure time physical activity. Experimental studies support the existence of fetal programming of physical activity, and show that exposure to exercise during IUGR individuals' life improves metabolic outcomes but less effect was seen on muscle architecture or function. Alterations in muscle strength and metabolism, as well as altered aerobic performance, may predispose IUGR individuals to be spontaneously less physically active, suggesting that this population may be an important target for preventive interventions. Although very heterogeneous, the different studies allow us to infer that physical activity may have beneficial effects especially for individuals that are more vulnerable to metabolic modifications such as those with IUGR. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.
Dimitrova, Julia; Hogan, Michael; Khader, Patrick; O'Hora, Denis; Kilmartin, Liam; Walsh, Jane C; Roche, Richard; Anderson-Hanley, Cay
2017-10-01
Physical exercise has been shown to improve cognitive and neural functioning in older adults. The current study compared the effects of an acute bout of physical exercise with a bout of interactive mental and physical exercise (i.e., "exergaming") on executive (Stroop) task performance and event-related potential (ERP) amplitudes in younger and older adults. Results revealed enhanced executive task performance in younger and older adults after exercise, with no differences in performance between exercise conditions. Stroop (RT) performance in older adults improved more than in younger adults from pre- to post-exercise. A significant increase in EEG amplitude from pre- to post-exercise was found at the Cz site from 320 to 700 ms post-stimulus for both younger and older adults, with older adults demonstrating a larger Stroop interference effect. While younger adults exhibited overall greater EEG amplitudes than older adults, they showed no differences between congruent and incongruent trials (i.e., minimal interference). Compared to peers with higher BMI (body mass index), older adults with lower BMI showed a greater reduction in Stroop interference effects from pre- to post-exercise. The beneficial effects of an acute bout of physical exercise on cognitive and neural functioning in younger and older adults were confirmed, with no difference between standard exercise and exergaming. Findings suggest that BMI, sometimes used as a proxy for fitness level, may modulate benefits that older adults derive from an acute bout of exercise. Findings have implications for future research that seeks to investigate unique effects of exergaming when compared to standard physical exercise.
Water and electrolytes. [in human bodies
NASA Technical Reports Server (NTRS)
Greenleaf, J. E.; Harrison, M. H.
1986-01-01
It has been found that the performance of the strongest and fittest people will deteriorate rapidly with dehydration. The present paper is concerned with the anatomy of the fluid spaces in the body, taking into account also the fluid shifts and losses during exercise and their effects on performance. Total body water is arbitrarily divided into that contained within cells (cellular) and that located outside the cells (extracellular). The anatomy of body fluid compartments is considered along with the effects of exercise on body water, fluid shifts with exercise, the consequences of sweating, dehydration and exercise, heat acclimatization and endurance training, the adverse effects of dehydration, thirst and drinking during exercise, stimuli for drinking, and water, electrolyte, and carbohydrate replacement during exercise. It is found that the deterioration of physical exercise performance due to dehydration begins when body weight decreases by about 1 percent.
Fullagar, Hugh H K; Skorski, Sabrina; Duffield, Rob; Hammes, Daniel; Coutts, Aaron J; Meyer, Tim
2015-02-01
Although its true function remains unclear, sleep is considered critical to human physiological and cognitive function. Equally, since sleep loss is a common occurrence prior to competition in athletes, this could significantly impact upon their athletic performance. Much of the previous research has reported that exercise performance is negatively affected following sleep loss; however, conflicting findings mean that the extent, influence, and mechanisms of sleep loss affecting exercise performance remain uncertain. For instance, research indicates some maximal physical efforts and gross motor performances can be maintained. In comparison, the few published studies investigating the effect of sleep loss on performance in athletes report a reduction in sport-specific performance. The effects of sleep loss on physiological responses to exercise also remain equivocal; however, it appears a reduction in sleep quality and quantity could result in an autonomic nervous system imbalance, simulating symptoms of the overtraining syndrome. Additionally, increases in pro-inflammatory cytokines following sleep loss could promote immune system dysfunction. Of further concern, numerous studies investigating the effects of sleep loss on cognitive function report slower and less accurate cognitive performance. Based on this context, this review aims to evaluate the importance and prevalence of sleep in athletes and summarises the effects of sleep loss (restriction and deprivation) on exercise performance, and physiological and cognitive responses to exercise. Given the equivocal understanding of sleep and athletic performance outcomes, further research and consideration is required to obtain a greater knowledge of the interaction between sleep and performance.
Gifford, Jayson R; Trinity, Joel D; Layec, Gwenael; Garten, Ryan S; Park, Song-Young; Rossman, Matthew J; Larsen, Steen; Dela, Flemming; Richardson, Russell S
2015-10-15
This study sought to determine if qualitative alterations in skeletal muscle mitochondrial respiration, associated with decreased mitochondrial efficiency, contribute to exercise intolerance in patients with chronic obstructive pulmonary disease (COPD). Using permeabilized muscle fibers from the vastus lateralis of 13 patients with COPD and 12 healthy controls, complex I (CI) and complex II (CII)-driven State 3 mitochondrial respiration were measured separately (State 3:CI and State 3:CII) and in combination (State 3:CI+CII). State 2 respiration was also measured. Exercise tolerance was assessed by knee extensor exercise (KE) time to fatigue. Per milligram of muscle, State 3:CI+CII and State 3:CI were reduced in COPD (P < 0.05), while State 3:CII and State 2 were not different between groups. To determine if this altered pattern of respiration represented qualitative changes in mitochondrial function, respiration states were examined as percentages of peak respiration (State 3:CI+CII), which revealed altered contributions from State 3:CI (Con 83.7 ± 3.4, COPD 72.1 ± 2.4%Peak, P < 0.05) and State 3:CII (Con 64.9 ± 3.2, COPD 79.5 ± 3.0%Peak, P < 0.05) respiration, but not State 2 respiration in COPD. Importantly, a diminished contribution of CI-driven respiration relative to the metabolically less-efficient CII-driven respiration (CI/CII) was also observed in COPD (Con 1.28 ± 0.09, COPD 0.81 ± 0.05, P < 0.05), which was related to exercise tolerance of the patients (r = 0.64, P < 0.05). Overall, this study indicates that COPD is associated with qualitative alterations in skeletal muscle mitochondria that affect the contribution of CI and CII-driven respiration, which potentially contributes to the exercise intolerance associated with this disease.
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/
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.
Ekwall, Anna; Lindberg, Asa; Magnusson, Måns
2009-01-01
Dizziness is a very common complaint. The frequency of dizziness increases with age. It affects quality of life negatively for older persons in several ways. This study intended to investigate which variables (physical activity, loneliness, health complaints, need of help for daily living and falls) differed between those with and without dizziness and also to investigate which factors affected quality of life among older persons with dizziness. An age-stratified, randomised sample of senior citizens - aged 75 or older - living in the south of Sweden (n = 4,360) answered a questionnaire concerning demographic data, social network, health complaints and diseases, feelings of loneliness, quality of life (Short Form 12), frequency of falls and activities. Dizziness was associated with an increased risk of falling. Falls in the last 3 months were reported in 31% of the subjects with dizziness compared to 15% among those without (p < 0.001). Dizziness also correlated with depression, with 42.5% feeling depressed among the elderly reporting dizziness as compared with 13.2%. Exercise, both light (i.e. go for a walk) or heavy (i.e. work in the garden), correlated with reduced risk of low quality of life among older, dizzy persons, both mental (light exercise OR 0.58; heavy OR 0.48) and physical (light OR 0.62; heavy OR 0.21). The proportion of dizzy persons doing light exercise was 75.6% versus 87.4% among the not dizzy (p < 0.001). Exercise reduces the risk of falling and the risk of being depressed, and increases quality of life. Even light exercise seems beneficial both for improving quality of life and to decrease the risk of falling, which in turn will lower the mortality rate. Older persons reporting dizziness should be encouraged and perhaps helped to exercise. If one could increase physical activity among the elderly, it would reduce the number of falls, diminish medical costs, suffering for the individual, and be of paramount medicosocial importance for society.
Antunes, Hanna Karen Moreira; Leite, Geovana Silva Fogaça; Lee, Kil Sun; Barreto, Amaury Tavares; Santos, Ronaldo Vagner Thomatieli Dos; Souza, Helton de Sá; Tufik, Sergio; de Mello, Marco Tulio
2016-03-15
The aim of this study was to identify the possible association between biochemical markers of exercise addiction and affective parameters in a sample of athletes during 2weeks of withdrawal exercise. Eighteen male runners were distributed into a control group (n=10) composed of runners without exercise addiction symptoms and an exercise addiction group (n=8) composed of runners with exercise addiction symptoms. The volunteers performed a baseline evaluation that included affective questionnaires, blood samples, body composition and an aerobic test performed at ventilatory threshold I. After the baseline evaluation, the groups started an exercise withdrawal period that was sustained for 2weeks. During exercise withdrawal, an actigraph accelerometer was used to monitor the movement index, and CK and LDH were measured in blood samples to validate the non-exercise practice. At the end of the exercise withdrawal period, a blood collection, aerobic test and mood scale was performed in the re-test. The results showed that at the end of the experimental protocol, when compared with the control group, the exercise addiction group showed an increase in depression, confusion, anger, fatigue and decreased vigor mood that improved post-exercise, along with low levels of anandamide at all time-points evaluated and a modest increase in β-endorphin post-exercise. Moreover, the exercise addiction group showed a decrease in oxygen consumption and respiratory exchange ratio after the exercise withdrawal period, which characterized a detraining phenomenon. Our data suggest that a 2-week withdrawal exercise period resulted in an increase of negative mood in exercise addiction; additionally, exercise addiction showed low levels of anandamide. Copyright © 2016 Elsevier Inc. All rights reserved.
The Academic and Psychological Benefits of Exercise in Healthy Children and Adolescents
ERIC Educational Resources Information Center
Rasmussen, Martin; Laumann, Karin
2013-01-01
This review examines the psychological benefits exercise is connected to in healthy children and adolescents. Studies on the effect of exercise on academic performance, self-esteem, emotions, and mood were examined. Academic performance is found to be maintained when normal academic classes are reduced and replaced by an increase in exercise,…
Pontifex, Matthew B; Saliba, Brian J; Raine, Lauren B; Picchietti, Daniel L; Hillman, Charles H
2013-03-01
To examine the effect of a single bout of moderate-intensity aerobic exercise on preadolescent children with attention-deficit/hyperactivity disorder (ADHD) using objective measures of attention, brain neurophysiology, and academic performance. Using a within-participants design, task performance and event-related brain potentials were assessed while participants performed an attentional-control task following a bout of exercise or seated reading during 2 separate, counterbalanced sessions. Following a single 20-minute bout of exercise, both children with ADHD and healthy match control children exhibited greater response accuracy and stimulus-related processing, with the children with ADHD also exhibiting selective enhancements in regulatory processes, compared with after a similar duration of seated reading. In addition, greater performance in the areas of reading and arithmetic were observed following exercise in both groups. These findings indicate that single bouts of moderately intense aerobic exercise may have positive implications for aspects of neurocognitive function and inhibitory control in children with ADHD. Copyright © 2013 Mosby, Inc. All rights reserved.
Factors Influencing Amount of Weekly Exercise Time in Colorectal Cancer Survivors.
Chou, Yun-Jen; Lai, Yeur-Hur; Lin, Been-Ren; Liang, Jin-Tung; Shun, Shiow-Ching
Performing regular exercise of at least 150 minutes weekly has benefits for colorectal cancer survivors. However, barriers inhibit these survivors from performing regular exercise. The aim of this study was to explore exercise behaviors and significant factors influencing weekly exercise time of more than 150 minutes in colorectal cancer survivors. A cross-sectional study design was used to recruit participants in Taiwan. Guided by the ecological model of health behavior, exercise barriers were assessed including intrapersonal, interpersonal, and environment-related barriers. A multiple logistic regression was used to explore the factors associated with the amount of weekly exercise. Among 321 survivors, 57.0% of them had weekly exercise times of more than 150 minutes. The results identified multiple levels of significant factors related to weekly exercise times including intrapersonal factors (occupational status, functional status, pain, interest in exercise, and beliefs about the importance of exercise) and exercise barriers related to environmental factors (lack of time and bad weather). No interpersonal factors were found to be significant. Colorectal cancer survivors experienced low levels of physical and psychological distress. Multiple levels of significant factors related to exercise time including intrapersonal factors as well as exercise barriers related to environmental factors should be considered. Healthcare providers should discuss with their patients how to perform exercise programs; the discussion should address multiple levels of the ecological model such as any pain problems, functional status, employment status, and time limitations, as well as community environment.
NASA Technical Reports Server (NTRS)
Thompson, William K.; Gallo, Christopher A.; Crentsil, Lawton; Lewandowski, Beth E.; Humphreys, Brad T.; DeWitt, John K.; Fincke, Renita S.; Mulugeta, Lealem
2015-01-01
The NASA Digital Astronaut Project (DAP) implements well-vetted computational models to predict and assess spaceflight health and performance risks, and to enhance countermeasure development. The DAP Musculoskeletal Modeling effort is developing computational models to inform exercise countermeasure development and to predict physical performance capabilities after a length of time in space. For example, integrated exercise device-biomechanical models can determine localized loading, which will be used as input to muscle and bone adaptation models to estimate the effectiveness of the exercise countermeasure. In addition, simulations of mission tasks can be used to estimate the astronaut's ability to perform the task after exposure to microgravity and after using various exercise countermeasures. The software package OpenSim (Stanford University, Palo Alto, CA) (Ref. 1) is being used to create the DAP biomechanical models and its built-in muscle model is the starting point for the DAP muscle model. During Exploration missions, such as those to asteroids and Mars, astronauts will be exposed to reduced gravity for extended periods. Therefore, the crew must have access to exercise countermeasures that can maintain their musculoskeletal and aerobic health. Exploration vehicles may have very limited volume and power available to accommodate such capabilities, even more so than the International Space Station (ISS). The exercise devices flown on Exploration missions must be designed to provide sufficient load during the performance of various resistance and aerobic/anaerobic exercises while meeting potential additional requirements of limited mass, volume and power. Given that it is not practical to manufacture and test (ground, analog and/or flight) all candidate devices, nor is it always possible to obtain data such as localized muscle and bone loading empirically, computational modeling can estimate the localized loading during various exercise modalities performed on a given device to help formulate exercise prescriptions and other operational considerations. With this in mind, NASA's Digital Astronaut Project (DAP) is supporting the Advanced Exercise Concepts (AEC) Project, Exercise Physiology and Countermeasures (ExPC) laboratory and NSBRI-funded researchers by developing and implementing well-validated computational models of exercises with advanced exercise device concepts. This report focuses specifically on lower-body resistance exercises performed with the Hybrid Ultimate Lifting Kit (HULK) device as a deliverable to the AEC Project.
Exercise as Countermeasure for Decrements of Performance and Mood During Long-Term Confinement
NASA Astrophysics Data System (ADS)
Schneider, Stefan; Piacentini, Maria F.; Meeusen, Romain; Brummer, Vera; Struder, Heiko K.
2008-06-01
In order to prepare for crewed exploratory missions to Moon and Mars, currently ESA is participating in two isolation studies, MARS 500 and on the antarctis station CONCORDIA. The aim of the present study is to identify exercise as a countermeasure to confinement addicted changes in mood. It is planned (1) to look at influences of exercise on the serotonergic system, which is known to have mood regulating effects and (2) to record changes in brain cortical activity due to exercise. Mood and performance tests will be carried out several times during the confinement. We hypothesize that impairments in mood due to the isolated and confined environment together with a lack of physical exercise lead to decreases in mental and perceptual motor performance whereas physical exercise linked with an activation of the serotonergic system will improve mood and therefore performance irrespectively of the environmental restrictions.
Human thermal responses during leg-only exercise in cold water.
Golden, F S; Tipton, M J
1987-10-01
1. Exercise during immersion in cold water has been reported by several authors to accelerate the rate of fall of core temperature when compared with rates seen during static immersion. The nature of the exercise performed, however, has always been whole-body in nature. 2. In the present investigation fifteen subjects performed leg exercise throughout a 40 min head-out immersion in water at 15 degrees C. The responses obtained were compared with those seen when the subjects performed an identical static immersion. 3. Aural and rectal temperatures were found to fall by greater amounts during static immersion. 4. It is concluded that 'the type of exercise performed' should be included in the list of factors which affect core temperature during cold water immersion.
Rogers, Richard; Harrison, Kimberly S; Rogstad, Jill E; LaFortune, Kathryn A; Hazelwood, Lisa L
2010-02-01
Traditionally, high levels of suggestibility have been widely assumed to be linked with diminished Miranda abilities, especially in relationship to the voluntariness of waivers. The current investigation examined suggestibility on the Gudjonsson Suggestibility Scales in a multisite study of pretrial defendants. One important finding was the inapplicability of British norms to American jurisdictions. Moreover, suggestibility appeared unrelated to Miranda comprehension, reasoning, and detainees' perceptions of police coercion. In testing rival hypotheses, defendants with high compliance had significantly lower Miranda comprehension and ability to reason about exercising Miranda rights than their counterparts with low compliance. Implications of these findings to forensic practice are examined.
Brennecke, Allan; Guimarães, Thiago M; Leone, Ricardo; Cadarci, Mauro; Mochizuki, Luiz; Simão, Roberto; Amadio, Alberto Carlos; Serrão, Júlio C
2009-10-01
The purpose of the present study was to investigate the effects of exercise order on the tonic and phasic characteristics of upper-body muscle activity during bench press exercise in trained subjects. The preexhaustion method involves working a muscle or a muscle group combining a single-joint exercise immediately followed by a multi-joint exercise (e.g., flying exercise followed by bench press exercise). Twelve subjects performed 1 set of bench press exercises with and without the preexhaustion method following 2 protocols (P1-flying before bench press; P2-bench press). Both exercises were performed at a load of 10 repetition maximum (10RM). Electromyography (EMG) sampled at 1 kHz was recorded from the pectoralis major (PM), anterior deltoid (DA), and triceps brachii (TB). Kinematic data (60 Hz) were synchronized to define upward and downward phases of exercise. No significant (p > 0.05) changes were seen in tonic control of PM and DA muscles between P1 and P2. However, TB tonic aspect of neurophysiologic behavior of motor units was significantly higher (p < 0.05) during P1. Moreover, phasic control of PM, DA, and TB muscles were not affected (p > 0.05). The kinematic pattern of movement changed as a result of muscular weakness in P1. Angular velocity of the right shoulder performed during the upward phase of the bench press exercise was significantly slower (p < 0.05) during P1. Our results suggest that the strategies set by the central nervous system to provide the performance required by the exercise are held constant throughout the exercise, but the tonic aspects of the central drive are increased so as to adapt to the progressive occurrence of the neuromuscular fatigue. Changes in tonic control as a result of the muscular weakness and fatigue can cause changes in movement techniques. These changes may be related to limited ability to control mechanical loads and mechanical energy transmission to joints and passive structures.
Cochrane, D J; Booker, H R; Mundel, T; Barnes, M J
2013-11-01
Intermittent pneumatic compression (IPC) has gained rapid popularity as a post-exercise recovery modality. Despite its widespread use and anecdotal claims for enhancing muscle recovery there is no scientific evidence to support its use. 10 healthy, active males performed a strenuous bout of eccentric exercise (3 sets of 100 repetitions) followed by IPC treatment or control performed immediately after exercise and at 24 and 48 h post-exercise. Muscular performance measurements were taken prior to exercise and 24, 48 and 72 h post-exercise and included single-leg vertical jump (VJ) and peak and average isometric [knee angle 75º] (ISO), concentric (CON) and eccentric (ECC) contractions performed at slow (30° · s⁻¹) and fast (180° · s⁻¹) velocities. Plasma creatine kinase (CK) samples were taken at pre- and post-exercise 24, 48 and 72 h. Strenuous eccentric exercise resulted in a significant decrease in peak ISO, peak and average CON (30° · s⁻¹) at 24 h compared to pre-exercise for both IPC and control, however VJ performance remained unchanged. There were no significant differences between conditions (IPC and control) or condition-time interactions for any of the contraction types (ISO, CON, ECC) or velocities (CON, ECC 30° · s⁻¹ and 180° · s⁻¹). However, CK was significantly elevated at 24 h compared to pre-exercise in both conditions (IPC and control). IPC did not attenuate muscle force loss following a bout of strenuous eccentric exercise in comparison to a control. While IPC has been used in the clinical setting to treat pathologic conditions, the parameters used to treat muscle damage following strenuous exercise in healthy participants are likely to be very different than those used to treat pathologic conditions. © Georg Thieme Verlag KG Stuttgart · New York.
Immediate effects of different types of stretching exercises on badminton jump smash.
Jang, Hwi S; Kim, Daeho; Park, Jihong
2018-01-01
Since different types of stretching exercises may alter athletic performance, we compared the effects of three types of stretching exercises on badminton jump smash. Sixteen male collegiate badminton players performed one of three different stretching exercises in a counterbalanced order on different days. Static stretching had seven typical stretches, while dynamic stretching involved nine dynamic movements, and resistance dynamic stretching was performed with weighted vests and dumbbells. Before and after each stretching exercise, subjects performed 20 trials of jump smashes. Dependent measurements were the jump heights during jump smashes, velocities of jump-smashed shuttlecocks, and drop point of jump-smashed shuttlecocks. To test the effects of each stretching exercise, we performed mixed model ANOVAs and calculated between-time effect sizes (ES). Each stretching exercise improved the jump heights during jump smashes (type main effect: F(2,75)=1.19, P=0.31; static stretching: 22.1%, P<0.01, ES=0.98; dynamic stretching: 30.1%, P<0.01, ES=1.49; resistance dynamic stretching: 17.7%, P=0.03, ES=0.98) and velocities of jump-smashed shuttlecocks (type main effect: F(2,75)=2.18, P=0.12; static stretching: 5.7%, P=0.61, ES=0.39; dynamic stretching: 3.4%, P=0.94, ES=0.28; resistance dynamic stretching: 6%, P=0.50, ES=0.66). However, there were no differences among the stretching exercises for any measurement. The drop point of jump-smashed shuttlecocks did not change (interaction: F(2,75)=0.88, P=0.42). All stretching exercises improved badminton jump smash performance, but we could not determine the best protocol. Since badminton requires high-speed movement and explosive force, we suggest performing dynamic stretching or resistance dynamic stretching.
Changes in stature following plyometric drop-jump and pendulum exercises.
Fowler, N E; Lees, A; Reilly, T
1997-12-01
The aim of this study was to compare the changes in stature following the performance of plyometric exercises using drop-jumps and a pendulum swing. Eight male participants aged 21.7 +/- 1.8 years with experience of plyometric training gave their informed consent to act as participants. Participants undertook two exercise regimens and a 15-min standing test in a random order. The exercises entailed the performance of 50 drop-jumps from a height of 0.28 m or 50 pendulum rebounds. Participants were instructed to perform maximal jumps or rebounds using a 'bounce' style. Measurements of stature were performed after a 20-min period of standing (pre-exercise), 2-min after exercise (post-exercise) and after a 20-min standing recovery (recovery). Back pain and muscle soreness were assessed using an analogue-visual scale, at each of the above times and also 24 and 36 h after the test. Peak torque during isokinetic knee extension at 1.04 rads-1 was measured immediately before and after the exercise bouts, to assess the degree of muscular fatigue. Ground/wall reaction force data were recorded using a Kistler force platform mounted in the floor for drop-jumps and vertically on the rebound wall for pendulum exercises. Drop-jumps resulted in the greatest (p < 0.05) change in stature (-2.71 +/- 0.8 mm), compared to pendulum exercises (-1.77 +/- 0.7 mm) and standing (-0.39 +/- 0.2 mm). Both exercise regimens resulted in a significant (p < 0.01) decrease in stature when compared to the standing condition. Drop-jumps resulted in significantly greater peak impact forces (p < 0.05) than pendulum exercises (drop-jumps = 3.2 +/- 0.5 x body weight, pendulum = 2.6 +/- 0.5 x body weight). The two exercise conditions both invoked a small degree of muscle soreness but there were no significant differences between conditions. Both exercise regimens resulted in a non-significant decrease in peak torque indicating a similar degree of muscular fatigue. Based on the lower shrinkage resulted and lower peak forces, it can be concluded that pendulum exercises pose a lower injury potential to the lower back than drop-jumps performed from a height of 28 cm.
Hypoglycemia and endurance exercise: dietary considerations.
Rutherford, W J
1990-01-01
Until recently, common dietary prescription for chronic hypoglycemia has been a high-protein, low-carbohydrate regimen (Airola, 1977; Danowski, 1978). Increasing evidence suggests, however, that a diet rich in complex carbohydrates may be more suitable for those involved in endurance exercise (Costill & Miller, 1980; Sherman & Costill, 1984). Although little original research has been undertaken which deals with the effects of performance-enhancing nutritional techniques on the hypoglycemic exerciser, such practices need to be examined in order to understand the mechanisms involved. Specifically, carbohydrate loading would seem to be as important, if not more so, to the hypoglycemic individual as a means of supercompensating glycogen stores prior to endurance performance. The roles of pre-exercise supplements and carbohydrate feedings during exercise in this context are less clear. Although results are mixed, increasing evidence (Snyder et al., 1983; Okano et al., 1988) suggests that carbohydrates may be consumed before exercise with beneficial effects on performance. Because of rapid gastric emptying characteristic of reactive hypoglycemia, it would appear that pre-exercise supplementation may be of particular value to the hypoglycemic exerciser. Further, recent studies (Bergstrom & Hultman, 1967; Coyle et al., 1983; Foster et al., 1986; Leatt & Jacobs, 1986; Horton, 1988) indicate that carbohydrate solutions taken during exercise are effective in maintaining serum glucose levels and improving endurance performance. Careful monitoring of nutritional factors would appear to be critical in creating a suitable dietary environment for the hypoglycemic endurance exerciser.
An acute bout of localized resistance exercise can rapidly improve inhibitory control
Tsukamoto, Hayato; Suga, Tadashi; Takenaka, Saki; Takeuchi, Tatsuya; Tanaka, Daichi; Hamaoka, Takafumi; Hashimoto, Takeshi; Isaka, Tadao
2017-01-01
The positive effect of acute resistance exercise on executive function, such as inhibitory control (IC), is poorly understood. Several previous studies have demonstrated this effect using whole-body resistance exercise. However, it remains unclear whether localized resistance exercise performed using only limited muscle groups could also acutely improve IC. Thus, the present study examined the effect of an acute bout of localized resistance exercise on IC. Twelve healthy men performed a color-word Stroop task (CWST) before and immediately after the experimental conditions, which consisted of 2 resistance exercises and a resting control (CON). Bilateral knee extension was used to create 2 resistance exercise conditions: light-intensity resistance exercise (LRE) and high-intensity resistance exercise (HRE) conditions, which were 40% and 80% of one-repetition maximum, respectively. The resistance exercise session was programmed for 6 sets with 10 repetitions per set. The CWST-measured IC was significantly improved immediately after both LRE and HRE, but it did not improve immediately after CON. However, the improved IC was significantly greater in HRE than in LRE. The present findings showed that IC could be rapidly improved by an acute bout of localized resistance exercise, especially with high-intensity. Therefore, we suggest that in addition to whole-body resistance exercise, localized resistance exercise performed using limited muscle groups may be sufficient for improving IC. PMID:28877232
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.
Frith, James; Day, Christopher P; Robinson, Lisa; Elliott, Chris; Jones, David E J; Newton, Julia L
2010-01-01
The management of non-alcoholic liver disease (NAFLD) concerns lifestyle modification and exercise; however, adherence is poor. Factors such as lack of confidence to exercise, poor understanding of the benefits of exercise, and a fear of falling all influence engagement in physical activity. To increase exercise in NAFLD it is important to understand the barriers to performing it. Three chronic liver disease cohorts were identified from the Newcastle Liver Database: NAFLD (n=230), alcoholic liver disease (ALD, n=110) and primary biliary cirrhosis (PBC, n=97). Assessment tools were completed by all subjects: Outcome Expectation for Exercise Scale (OEES, understanding the benefits of exercise, lower scores indicate greater understanding), Self-Efficacy for Exercise Scale (SEES, confidence to exercise), Falls Efficacy Scale-International (FES-I, higher scores indicate greater fear of falling). Activity was analysed from a functional perspective using the PROMIS-HAQ. Understanding the benefits of exercise was similar across each group [median OEES scores: NAFLD 2.38 (range 0.0-5.0), ALD 2.25 (0.0-5.0), PBC 2.28 (1.0-5.0), p=0.6]. In NAFLD confidence to exercise was significantly lower [median SEES score 0.0 (0.0-10.0), PBC 4.5 (0.0-10.0), p<0.001]. Fear of falling was similar in NAFLD and PBC, and greatest in ALD [22 (0-64), 22 (3-64), 30 (0-64), p=0.044]. In NAFLD, fear of falling was independently associated with increasing difficulty performing activity. NAFLD patients understand the benefits of exercise but lack confidence to perform it. Fear of falling was independently associated with more difficulty performing activity. Fear of falling and confidence are modifiable and potential targets to improve uptake and adherence for exercise intervention.
The Effect of Acute Exercise on Affect and Arousal in Inpatient Mental Health Consumers.
Stanton, Robert; Reaburn, Peter; Happell, Brenda
2016-09-01
Acute exercise performed at a self-selected intensity improves affect and may improve long-term adherence. Similarly, in people with severe depression, acute aerobic exercise performed at self-selected intensity improves affect and arousal. However, the relationship between changes in affect and arousal and perceived exercise intensity in people with mental illness has not been evaluated. Affect and arousal were assessed immediately prior to, and immediately following, a group exercise program performed at a self-selected intensity in 40 inpatient mental health consumers who received a diagnosis of anxiety or bipolar or depressive disorders. Exercise intensity was assessed immediately after exercise. Postexercise affect was significantly improved for people with bipolar and depressive disorders but not for people with anxiety disorders. For the group as a whole, results showed a significant curvilinear relationship between ratings of perceived exertion and postexercise affect. These data will inform the development and delivery of future exercise interventions for inpatient mental health consumers.
Exercise-induced muscle damage and running economy in humans.
Assumpção, Cláudio de Oliveira; Lima, Leonardo Coelho Rabello; Oliveira, Felipe Bruno Dias; Greco, Camila Coelho; Denadai, Benedito Sérgio
2013-01-01
Running economy (RE), defined as the energy demand for a given velocity of submaximal running, has been identified as a critical factor of overall distance running performance. Plyometric and resistance trainings, performed during a relatively short period of time (~15-30 days), have been successfully used to improve RE in trained athletes. However, these exercise types, particularly when they are unaccustomed activities for the individuals, may cause delayed onset muscle soreness, swelling, and reduced muscle strength. Some studies have demonstrated that exercise-induced muscle damage has a negative impact on endurance running performance. Specifically, the muscular damage induced by an acute bout of downhill running has been shown to reduce RE during subsequent moderate and high-intensity exercise (>65% VO₂max). However, strength exercise (i.e., jumps, isoinertial and isokinetic eccentric exercises) seems to impair RE only for subsequent high-intensity exercise (~90% VO₂max). Finally, a single session of resistance exercise or downhill running (i.e., repeated bout effect) attenuates changes in indirect markers of muscle damage and blunts changes in RE.
20 CFR 404.1071 - Ministers and members of religious orders.
Code of Federal Regulations, 2010 CFR
2010-04-01
... poverty, the services you perform in the exercise of your ministry or in the exercise of duties required... poverty, the services you perform in the exercise of your duties required by the order may be covered as...
Caffeinated nitric oxide-releasing lozenge improves cycling time trial performance.
Lee, J; Kim, H T; Solares, G J; Kim, K; Ding, Z; Ivy, J L
2015-02-01
Boosting nitric oxide production during exercise by various means has been found to improve exercise performance. We investigated the effects of a nitric oxide releasing lozenge with added caffeine (70 mg) on oxygen consumption during steady-state exercise and cycling time trial performance using a double-blinded randomized, crossover experimental design. 15 moderately trained cyclists (7 females and 8 males) were randomly assigned to ingest the caffeinated nitric oxide lozenge or placebo 5 min before exercise. Oxygen consumption and blood lactate were assessed at rest and at 50%, 65% and 75% maximal oxygen consumption. Exercise performance was assessed by time to complete a simulated 20.15 km cycling time-trial course. No significant treatment effects for oxygen consumption or blood lactate at rest or during steady-state exercise were observed. However, time-trial performance was improved by 2.1% (p<0.01) when participants consumed the nitric oxide lozenge (2,424±69 s) compared to placebo (2,476±78 s) and without a significant difference in rating of perceived exertion. These results suggest that acute supplementation with a caffeinated nitric oxide releasing lozenge may be a practical and effective means of improving aerobic exercise performance. © Georg Thieme Verlag KG Stuttgart · New York.
Comparison of trunk kinematics in trunk training exercises and throwing.
Stodden, David F; Campbell, Brian M; Moyer, Todd M
2008-01-01
Strength and conditioning professionals, as well as coaches, have emphasized the importance of training the trunk and the benefits it may have on sport performance and reducing the potential for injury. However, no data on the efficacy of trunk training support such claims. The purpose of this study was to examine the maximum differential trunk rotation and maximum angular velocities of the pelvis and upper torso of participants while they performed 4 trunk exercises (seated band rotations, cross-overs, medicine ball throws, and twisters) and compare these trunk exercise kinematics with the trunk kinematics demonstrated in actual throwing performance. Nine NCAA Division I baseball players participated in this study. Each participant's trunk kinematics was analyzed while he performed 5 repetitions of each exercise in both dominant and nondominant rotational directions. Results indicated maximum differentiated rotation in all 4 trunk exercises was similar to maximum differentiated rotation (approximately 50-60 degrees) demonstrated in throwing performance. Maximum angular velocities of the pelvis and upper torso in the trunk exercises were appreciably slower (approximately 50% or less) than the angular velocities demonstrated during throwing performance. Incorporating trunk training exercises that demonstrate sufficient trunk ranges of motion and velocities into a strength and conditioning program may help to increase ball velocity and/or decrease the risk injury.
Martial Art Training and Cognitive Performance in Middle-Aged Adults.
Douris, Peter; Douris, Christopher; Balder, Nicole; LaCasse, Michael; Rand, Amir; Tarapore, Freya; Zhuchkan, Aleskey; Handrakis, John
2015-09-29
Cognitive performance includes the processes of attention, memory, processing speed, and executive functioning, which typically declines with aging. Previous research has demonstrated that aerobic and resistance exercise improves cognitive performance immediately following exercise. However, there is limited research examining the effect that a cognitively complex exercise such as martial art training has on these cognitive processes. Our study compared the acute effects of 2 types of martial art training to aerobic exercise on cognitive performance in middle-aged adults. We utilized a repeated measures design with the order of the 3 exercise conditions randomly assigned and counterbalanced. Ten recreational middle-aged martial artists (mean age = 53.5 ± 8.6 years) participated in 3 treatment conditions: a typical martial art class, an atypical martial art class, and a one-hour walk at a self-selected speed. Cognitive performance was assessed by the Stroop Color and Word test. While all 3 exercise conditions improved attention and processing speed, only the 2 martial art conditions improved the highest order of cognitive performance, executive function. The effect of the 2 martial art conditions on executive function was not different. The improvement in executive function may be due to the increased cortical demand required by the more complex, coordinated motor tasks of martial art exercise compared to the more repetitive actions of walking.
Martial Art Training and Cognitive Performance in Middle-Aged Adults
Douris, Peter; Douris, Christopher; Balder, Nicole; LaCasse, Michael; Rand, Amir; Tarapore, Freya; Zhuchkan, Aleskey; Handrakis, John
2015-01-01
Cognitive performance includes the processes of attention, memory, processing speed, and executive functioning, which typically declines with aging. Previous research has demonstrated that aerobic and resistance exercise improves cognitive performance immediately following exercise. However, there is limited research examining the effect that a cognitively complex exercise such as martial art training has on these cognitive processes. Our study compared the acute effects of 2 types of martial art training to aerobic exercise on cognitive performance in middle-aged adults. We utilized a repeated measures design with the order of the 3 exercise conditions randomly assigned and counterbalanced. Ten recreational middle-aged martial artists (mean age = 53.5 ± 8.6 years) participated in 3 treatment conditions: a typical martial art class, an atypical martial art class, and a one-hour walk at a self-selected speed. Cognitive performance was assessed by the Stroop Color and Word test. While all 3 exercise conditions improved attention and processing speed, only the 2 martial art conditions improved the highest order of cognitive performance, executive function. The effect of the 2 martial art conditions on executive function was not different. The improvement in executive function may be due to the increased cortical demand required by the more complex, coordinated motor tasks of martial art exercise compared to the more repetitive actions of walking. PMID:26672872
Steinberg, Martin; Leoutsakos, Jeannie-Marie Sheppard; Podewils, Laura Jean; Lyketsos, C G
2009-07-01
To determine the feasibility and efficacy of a home-based exercise intervention program to improve the functional performance of patients with Alzheimer's Disease (AD). Twenty-seven home-dwelling patients with AD were randomized to either an exercise intervention program delivered by their caregivers or a home safety assessment control. Measures of functional performance (primary), cognition, neuropsychiatric symptoms, quality of life and caregiver burden (secondary) were obtained at baseline and at 6 and 12 weeks following randomization. For each outcome measure, intent-to-treat analyses using linear random effects models were performed. Feasibility and adverse events were also assessed. Adherence to the exercise program was good. On the primary outcomes (functional performance) patients in the exercise group demonstrated a trend for improved performance on measures of hand function and lower extremity strength. On secondary outcome measures, trends toward worse depression and lower quality of life ratings were noted. The physical exercise intervention developed for the study, delivered by caregivers to home-dwelling patients with AD, was feasible and was associated with a trend for improved functional performance in this group of frail patients. Given the limited efficacy to date of pharmacotherapies for AD, further study of exercise intervention, in a variety of care setting, is warranted.
Barriers to performing stretching exercises among Korean-Chinese female migrant workers in Korea.
Lee, Hyeonkyeong; Wilbur, JoEllen; Chae, Duckhee; Lee, Kyongeun; Lee, Meenhye
2015-01-01
The purpose of this study was to investigate the barriers to performing stretching exercise experienced by Korean-Chinese female migrant workers during a community-based 12-week stretching exercise intervention trial. Qualitative secondary data analysis was conducted using telephone counseling interview transcripts from 27 middle-aged, Korean-Chinese migrant women workers. A semistructured interview question asking barriers to performing stretching exercise was given to women who did not adhere to recommended stretching exercise. During the 12-week home-based stretching exercise intervention trial, six telephone calls were made to participants biweekly to elicit barriers to performing stretching exercise. Directed content analysis approach was utilized using three barrier categories: intrapersonal, interpersonal, and work-related environmental factors based on the ecological model. Participants experienced an average of 2.5 barriers during the study period. Intrapersonal barriers included lack of time and lack of motivation, and interpersonal barriers included no family to provide support and also a feeling resistance from coworkers. Work-related environmental barriers included frequent job changes, long working hours, lack of rest time, and unpredictable job demands. The findings highlight that migrant workers in Korea face unique work-related difficulties which present barriers to exercise. © 2014 Wiley Periodicals, Inc.
Efficacy of Carbohydrate Ingestion on CrossFit Exercise Performance
Rountree, Jaden A.; Krings, Ben M.; Peterson, Timothy J.; Thigpen, Adam G.; McAllister, Matthew J.; Holmes, Megan E.
2017-01-01
The efficacy of carbohydrate (CHO) ingestion during high-intensity strength and conditioning type exercise has yield mixed results. However, little is known about shorter duration high-intensity exercise such as CrossFit. The purpose of this study was to investigate the performance impact of CHO ingestion during high-intensity exercise sessions lasting approximately 30 min. Eight healthy males participated in a total of four trials; two familiarizations, a CHO trial, and a similarly flavored, non-caloric placebo (PLA) trial. CrossFit’s “Fight Gone Bad Five” (FGBF) workout of the day was the exercise model which incorporated five rounds of maximal repetition exercises, wall throw, box jump, sumo deadlift high pull, push press, and rowing, followed by one minute of rest. Total repetitions and calories expended were summated from each round to quantify total work (FGBF score). No difference was found for the total work between CHO (321 ± 51) or PLA (314 ± 52) trials (p = 0.38). There were also no main effects (p > 0.05) for treatment comparing exercise performance across rounds. Based on the findings of this study, it does not appear that ingestion of CHO during short duration, high-intensity CrossFit exercise will provide a beneficial performance effect.
Effect of local cooling on short-term, intense exercise.
Kwon, Young S; Robergs, Robert A; Schneider, Suzanne M
2013-07-01
The widespread belief that local cooling impairs short-term, strenuous exercise performance is controversial. Eighteen original investigations involving cooling before and intermittent cooling during short-term, intensive exercise are summarized in this review. Previous literature examining short-term intensive exercise and local cooling primarily has been limited to the effects on muscle performance immediately or within minutes following cold application. Most previous cooling studies used equal and longer than 10 minutes of pre-cooling, and found that cooling reduced strength, performance and endurance. Because short duration, high intensity exercise requires adequate warm-up to prepare for optimal performance, prolonged pre-cooling is not an effective method to prepare for this type of exercise. The literature related to the effect of acute local cooling immediately before short duration, high intensity isotonic exercise such as weight lifting is limited. However, local intermittent cooling during short-term, high intense exercise may provide possible beneficial effects; first, by pain reduction, caused by an "irritation effect" from hand thermal receptors which block pain sensation, or second, by a cooling effect, whereby stimulation of hand thermal receptors or a slight lowering of blood temperature might alter central fatigue.
The Feasibility of performing resistance exercise with acutely ill hospitalized older adults
Mallery, Laurie H; MacDonald, Elizabeth A; Hubley-Kozey, Cheryl L; Earl, Marie E; Rockwood, Kenneth; MacKnight, Chris
2003-01-01
Background For older adults, hospitalization frequently results in deterioration of mobility and function. Nevertheless, there are little data about how older adults exercise in the hospital and definitive studies are not yet available to determine what type of physical activity will prevent hospital related decline. Strengthening exercise may prevent deconditioning and Pilates exercise, which focuses on proper body mechanics and posture, may promote safety. Methods A hospital-based resistance exercise program, which incorporates principles of resistance training and Pilates exercise, was developed and administered to intervention subjects to determine whether acutely-ill older patients can perform resistance exercise while in the hospital. Exercises were designed to be reproducible and easily performed in bed. The primary outcome measures were adherence and participation. Results Thirty-nine ill patients, recently admitted to an acute care hospital, who were over age 70 [mean age of 82.0 (SD= 7.3)] and ambulatory prior to admission, were randomized to the resistance exercise group (19) or passive range of motion (ROM) group (20). For the resistance exercise group, participation was 71% (p = 0.004) and adherence was 63% (p = 0.020). Participation and adherence for ROM exercises was 96% and 95%, respectively. Conclusion Using a standardized and simple exercise regimen, selected, ill, older adults in the hospital are able to comply with resistance exercise. Further studies are needed to determine if resistance exercise can prevent or treat hospital-related deterioration in mobility and function. PMID:14531932
Westerdahl, Elisabeth; Lindmark, Birgitta; Eriksson, Tomas; Friberg, Orjan; Hedenstierna, Göran; Tenling, Arne
2005-11-01
To investigate the effects of deep-breathing exercises on pulmonary function, atelectasis, and arterial blood gas levels after coronary artery bypass graft (CABG) surgery. In a prospective, randomized trial, patients performing deep-breathing exercises (n = 48) were compared to a control group (n = 42) who performed no breathing exercises postoperatively. Patient management was similar in the groups in terms of assessment, positioning, and mobility. The patients in the deep-breathing group were instructed to perform breathing exercises hourly during daytime for the first 4 postoperative days. The exercises consisted of 30 slow, deep breaths performed with a positive expiratory pressure blow-bottle device (+ 10 cm H(2)O). Spirometric measurements, spiral CT (three transverse levels), arterial blood gas analysis, and scoring of subjective experience of the breathing exercises were performed on the fourth postoperative day. Atelectasis was only half the size in the deep-breathing group compared to the control group, amounting to 2.6 +/- 2.2% vs 4.7 +/- 5.7% (p = 0.045) at the basal level and 0.1 +/- 0.2% vs 0.3 +/- 0.5% (mean +/- SD) [p = 0.01] at the apical level. Compared to the control subjects, the patients in the deep-breathing group had a significantly smaller reduction in FVC (to 71 +/- 12%, vs 64 +/- 13% of the preoperative values; p = 0.01) and FEV(1) (to 71 +/- 11%, vs 65 +/- 13% of the preoperative values; p = 0.01). Arterial oxygen tension, carbon dioxide tension, fever, or length of ICU or hospital stay did not differ between the groups. In the deep-breathing group, 72% of the patients experienced a subjective benefit from the exercises. Patients performing deep-breathing exercises after CABG surgery had significantly smaller atelectatic areas and better pulmonary function on the fourth postoperative day compared to a control group performing no exercises.
Kresta, Julie Y; Oliver, Jonathan M; Jagim, Andrew R; Fluckey, James; Riechman, Steven; Kelly, Katherine; Meininger, Cynthia; Mertens-Talcott, Susanne U; Rasmussen, Christopher; Kreider, Richard B
2014-01-01
The purpose of this study was to examine the short-term and chronic effects of β-ALA supplementation with and without creatine monohydrate on body composition, aerobic and anaerobic exercise performance, and muscle carnosine and creatine levels in college-aged recreationally active females. Thirty-two females were randomized in a double-blind, placebo-controlled manner into one of four supplementation groups: β-ALA only (BA, n = 8), creatine only (CRE, n = 8), β-ALA and creatine combined (BAC, n = 9) and placebo (PLA, n = 7). Participants supplemented for four weeks included a loading phase for the creatine for week 1 of 0.3 g/kg of body weight and a maintenance phase for weeks 2-4 of 0.1 g/kg of body weight, with or without a continuous dose of β-ALA of 0.1 g/kg of body weight with doses rounded to the nearest 800 mg capsule providing an average of 6.1 ± 0.7 g/day of β-ALA. Participants reported for testing at baseline, day 7 and day 28. Testing sessions consisted of obtaining a resting muscle biopsy of the vastus lateralis, body composition measurements, performing a graded exercise test on the cycle ergometer for VO2peak with lactate threshold determination, and multiple Wingate anaerobic capacity tests. Although mean changes were consistent with prior studies and large effect sizes were noted, no significant differences were observed among groups in changes in muscle carnosine levels (BA 35.3 ± 45; BAC 42.5 ± 99; CRE 0.72 ± 27; PLA 13.9 ± 44%, p = 0.59). Similarly, although changes in muscle phosphagen levels after one week of supplementation were consistent with prior reports and large effect sizes were seen, no statistically significant effects were observed among groups in changes in muscle phosphagen levels and the impact of CRE supplementation appeared to diminish during the maintenance phase. Additionally, significant time × group × Wingate interactions were observed among groups for repeated sprint peak power normalized to bodyweight (p = 0.02) and rate of fatigue (p = 0.04). Results of the present study did not reveal any consistent additive benefits of BA and CRE supplementation in recreationally active women.
“Nutraceuticals” in relation to human skeletal muscle and exercise
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
Laurent, Mourot; Daline, Teffaha; Malika, Bouhaddi; Fawzi, Ounissi; Philippe, Vernochet; Benoit, Dugue; Catherine, Monpère; Jacques, Regnard
2009-04-01
Rehabilitation programs involving immersed exercises are more and more frequently used, with severe cardiac patients as well. This study investigated whether a rehabilitation program including water-based exercises has additional effects on the cardiovascular system compared with a traditional land-based training in heart disease patients. Twenty-four male stable chronic heart failure patients and 24 male coronary artery disease patients with preserved left ventricular function participated in the study. Patients took part in the rehabilitation program performing cycle endurance exercises on land. They also performed gymnastic exercises either on land (first half of the participants) or in water (second half). Resting plasma concentration of nitric oxide metabolites (nitrate and nitrite) and catecholamine were evaluated, and a symptom-limited exercise test on a cycle ergometer was performed before and after the rehabilitation program. In the groups performing water-based exercises, the plasma concentration of nitrates was significantly increased (P = 0.035 for chronic heart failure and P = 0.042 for coronary artery disease), whereas it did not significantly change in the groups performing gymnastic exercise on land. No changes in plasma catecholamine concentration occurred. In every group, the cardiorespiratory capacity of patients was significantly increased after rehabilitation. The water-based exercises seemed to effectively increase the basal level of plasma nitrates. Such changes may be related to an enhancement of endothelial function and may be of importance for the health of the patients.
Can an Inquiry Approach Improve College Student Learning in a Teaching Laboratory?
Cogan, John G.
2009-01-01
We present an inquiry-based, hands-on laboratory exercise on enzyme activity for an introductory college biology course for science majors. We measure student performance on a series of objective and subjective questions before and after completion of this exercise; we also measure performance of a similar cohort of students before and after completion of an existing, standard, “direct” exercise over the same topics. Although student performance on these questions increased significantly after completion of the inquiry exercise, it did not increase after completion of the control, standard exercise. Pressure to “cover” many complex topics as preparation for high-stakes examinations such as the Medical College Admissions Test may account for persistence of highly efficient, yet dubiously effective “cookbook” laboratory exercises in many science classes. PMID:19255136
NASA Technical Reports Server (NTRS)
Nazar, K.; Greenleaf, J. E.; Pohoska, E.; Turlejska, E.; Kaciuba-Uscilko, H.; Kozlowski, S.
1992-01-01
Physiological effects of restricted activity (RA) and subsequent retraining have been studied. Ten male mongrel dogs performed a submaximal exercise endurance test on a treadmill during kennel control, after 8 weeks of cage confinement and after eight weeks of retraining using the same treadmill protocol 1 h/d for 6 d/week. Data obtained show that RA reduces exercise endurance, the effectiveness of exercise thermoregulation, muscle glycogen stores, and the lipolytic response to exercise and to noradrenaline stimulation.
Individual Characteristics and Unit Performance: A Review of Research and Methods
1985-02-01
behavioral segments, improves performance. Simu- lation exercises , especially those employing new high-technology devices, provide surrogate...high-technology training simulation exercise MOB Military Occupational Specialty ORTT Operational Readiness Training Test-a field test REALTRAIN A...REAListic TRAINing simulation exercise SAM Surface-to-Air Missile SAT Scholastic Aptitude Test SQT Skill Qualification Test-an Army performance meas
Exercise Tolerance in Children With Early Onset Scoliosis: Growing Rod Treatment "Graduates".
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.
Jansen, Femke; Cnossen, Ingrid C; Eerenstein, Simone E J; Coupé, Veerle M H; Witte, Birgit I; van Uden-Kraan, Cornelia F; Doornaert, Patricia; Braunius, Weibel W; De Bree, Remco; Hardillo, José A U; Honings, Jimmie; Halmos, György B; Leemans, C René; Verdonck-de Leeuw, Irma M
2016-08-02
Total laryngectomy with or without adjuvant (chemo)radiation often induces speech, swallowing and neck and shoulder problems. Speech, swallowing and shoulder exercises may prevent or diminish these problems. The aim of the present paper is to describe the study, which is designed to investigate the effectiveness and cost-utility of a guided self-help exercise program built into the application "In Tune without Cords" among patients treated with total laryngectomy. Patients, up to 5 years earlier treated with total laryngectomy with or without (chemo)radiation will be recruited for participation in this study. Patients willing to participate will be randomized to the intervention or control group (1:1). Patients in the intervention group will be provided access to a guided self-help exercise program and a self-care education program built into the application "In Tune without Cords". Patients in the control group will only be provided access to the self-care education program. The primary outcome is the difference in swallowing quality (SWAL-QOL) between the intervention and control group. Secondary outcome measures address speech problems (SHI), shoulder disability (SDQ), quality of life (EORTC QLQ-C30, QLQ-H&N35 and EQ-5D), direct and indirect costs (adjusted iMCQ and iPCQ measures) and self-management (PAM). Patients will be asked to complete these outcome measures at baseline, immediately after the intervention or control period (i.e. at 3 months follow-up) and at 6 months follow-up. This randomized controlled trial will provide knowledge on the effectiveness of a guided self-help exercise program for patients treated with total laryngectomy. In addition, information on the value for money of such an exercise program will be provided. If this guided self-help program is (cost)effective for patients treated with total laryngectomy, the next step will be to implement this exercise program in current clinical practice. NTR5255 Protocol version 4 date September 2015.
Aspirin does not affect exercise performance.
Roi, G S; Garagiola, U; Verza, P; Spadari, G; Radice, D; Zecca, L; Cerretelli, P
1994-07-01
A single-blind, cross-over study was carried out to evaluate the effects of acetylsalicylic acid (ASA) on cardiorespiratory performance during exercise. Eighteen young men, 9 athletes and 9 untrained but active subjects, performed a progressive maximal exercise test on a cycle ergometer (30 watt, 3 min steps, starting at 60 watt) on three different occasions, after a single administration of plain aspirin (1000mg of ASA), chewable buffered aspirin (1000mg of ASA and 600 mg of calcium carbonate) and placebo. Continuous measurement of breath-by-breath ventilation, oxygen consumption, carbon dioxide output, respiratory frequency and heart rate was carried-out at rest and during the exercise test. Blood lactate concentration was measured just before the start of exercise and at the third minute of each step in order to detect the anaerobic threshold. The pharmacokinetics of aspirin during exercise was also investigated in ten of the eighteen participants. The analysis of all investigated variables did not show any statistically significant difference between treatments, suggesting that a single dose of 1000mg of aspirin does not affect physical performance during submaximal and maximal exercise.
Nassar, Cíntia Cristina Souza; Bondan, Eduardo Fernandes; Alouche, Sandra Regina
2009-09-01
Multiple sclerosis is a demyelinating disease of the central nervous system associated with varied levels of disability. The impact of early physiotherapeutic interventions in the disease progression is unknown. We used an experimental model of demyelination with the gliotoxic agent ethidium bromide and early aquatic exercises to evaluate the motor performance of the animals. We quantified the number of footsteps and errors during the beam walking test. The demyelinated animals walked fewer steps with a greater number of errors than the control group. The demyelinated animals that performed aquatic exercises presented a better motor performance than those that did not exercise. Therefore aquatic exercising was beneficial to the motor performance of rats in this experimental model of demyelination.
Lehnert, B E; Archuleta, D; Gurley, L R; Session, W; Behr, M J; Lehnert, N M; Stavert, D M
1995-01-01
Exercise performed after exposure to various pneumoedematogenic gases can increase the severity of pulmonary edema beyond that which occurs when exposure is followed by rest. The present study was performed to investigate the potential relationship between a preexisting breach in the lung's permeability status following exposure to an edematogenic gas (perfluoroisobutylene, PFIB) and the potentiating effects of postexposure exercise. Rats were exposed to a concentration of PFIB (100 mg/M3 for 10 min) that results in a unique postexposure latency period (approximately 8 h) prior to the occurrence of overt pulmonary edema. The study examined how exercise performed during and after the latency period affects the severity of the injurious response to this toxic gas. The initial results indicated that exercise performed during the post-PFIB exposure latency period does not potentiate the injurious response, as judged by conventional lung gravimetric and histopathological criteria, but when overt pulmonary edema was preexistent, exercise had a potentiating effect. Changes in lavageable protein were assessed as a more sensitive indicator of permeability changes that may occur during the latency period following PFIB exposure, and the study examined how exercise performed early during the latency period affects this index of pulmonary edema. The study also assessed whether PFIB-induced damage to lung cells is enhanced by exercise during the latency period by measuring lavageable lactate dehydrogenase activity. The results from these latter experiments suggest that a preexisting enhancement in lung permeability is not an absolute requirement for exercise to potentiate the pulmonary edematous response in lungs that are undergoing insidious injury, and that postexposure exercise does not enhance the cell-killing effects of PFIB as a mechanism underlying the exercise potentiating response. Conceivably, the ability of exercise to increase lavageable protein in the absence of a preexisting increase in lung permeability may be due to hyperventilation- and/or pulmonary hypertension-associated intercellular junctional changes that may occur during exercise. Additionally, it remains possible that exercise during PFIB-induced insideous lung injury results in an enhancement in the rate of transcellular transport of blood proteins onto the alveolar surface.
Biomarkers in Sports and Exercise: Tracking Health, Performance, and Recovery in Athletes
Fragala, Maren S.; Kavouras, Stavros A.; Queen, Robin M.; Pryor, John Luke; Casa, Douglas J.
2017-01-01
Abstract Lee, EC, Fragala, MS, Kavouras, SA, Queen, RM, Pryor, JL, and Casa, DJ. Biomarkers in sports and exercise: tracking health, performance, and recovery in athletes. J Strength Cond Res 31(10): 2920–2937, 2017—Biomarker discovery and validation is a critical aim of the medical and scientific community. Research into exercise and diet-related biomarkers aims to improve health, performance, and recovery in military personnel, athletes, and lay persons. Exercise physiology research has identified individual biomarkers for assessing health, performance, and recovery during exercise training. However, there are few recommendations for biomarker panels for tracking changes in individuals participating in physical activity and exercise training programs. Our approach was to review the current literature and recommend a collection of validated biomarkers in key categories of health, performance, and recovery that could be used for this purpose. We determined that a comprehensive performance set of biomarkers should include key markers of (a) nutrition and metabolic health, (b) hydration status, (c) muscle status, (d) endurance performance, (e) injury status and risk, and (f) inflammation. Our review will help coaches, clinical sport professionals, researchers, and athletes better understand how to comprehensively monitor physiologic changes, as they design training cycles that elicit maximal improvements in performance while minimizing overtraining and injury risk. PMID:28737585
Piana, N; Battistini, D; Urbani, L; Romani, G; Fatone, C; Pazzagli, C; Laghezza, L; Mazzeschi, C; De Feo, P
2013-04-01
To be successful, lifestyle intervention in obesity must take into account patients' views. The aim of the present study, conducted using a narrative-autobiographical approach, was to report on the perception of disease, food and physical exercise in a group of 80 obese patients during a structured multidisciplinary lifestyle intervention. Patients underwent lifestyle intervention, of three months' duration, structured in the following steps: 1) an initial medical examination; 2) an interview by a psychologist; 3) an assessment by a dietician, 4) a physical examination by a specialist in sports medicine; 5) an individualized program consisting of 24 sessions (two per week) of structured indoor exercise 6) eight sessions of group therapeutic education; 7) Nordic walking activity combined with walking excursions during weekends. All the narrative autobiographic texts obtained during the lifestyle intervention were submitted for content analysis; data were analysed according to the ''grounded theory'' method. According to patients' descriptions at the end of the intervention, lifestyle intervention resulted in enhanced self-efficacy and a reduction in their dependency on food and people; their fear of change was also diminished because, by undergoing intervention, they had experienced change. The findings made in the present qualitative analysis suggest that whenever multidisciplinary lifestyle intervention is planned for patients with obesity, it is of the utmost importance to tailor the approach while taking the following key aspects into account: motivation, barriers and/or facilitators in lifestyle change, patients' perceptions of obesity and relationship with food, diet and exercise. Copyright © 2011 Elsevier B.V. All rights reserved.
Mao, Tso-Yen; Fu, Li-Lan; Wang, Jong-Shyan
2011-08-01
Despite enhancing cardiopulmonary and muscular fitness, the effect of hypoxic exercise training (HE) on hemorheological regulation remains unclear. This study investigates how HE modulates erythrocyte rheological properties and further explores the underlying mechanisms in the hemorheological alterations. Twenty-four sedentary males were randomly divided into hypoxic (HE; n = 12) and normoxic (NE; n = 12) exercise training groups. The subjects were trained on 60% of maximum work rate under 15% (HE) or 21% (NE) O(2) condition for 30 min daily, 5 days weekly for 5 wk. The results demonstrated that HE 1) downregulated CD47 and CD147 expressions on erythrocytes, 2) decreased actin and spectrin contents in erythrocytes, 3) reduced erythrocyte deformability under shear flow, and 4) diminished erythrocyte volume changed by hypotonic stress. Treatment of erythrocytes with H(2)O(2) that mimicked in vivo prooxidative status resulted in the cell shrinkage, rigidity, and phosphatidylserine exposure, whereas HE enhanced the eryptotic responses to H(2)O(2). However, HE decreased the degrees of clotrimazole to blunt ionomycin-induced shrinkage, rigidity, and cytoskeleton breakdown of erythrocytes, referred to as Gardos effects. Reduced erythrocyte deformability by H(2)O(2) was inversely related to the erythrocyte Gardos effect on the rheological function. Conversely, NE intervention did not significantly change resting and exercise erythrocyte rheological properties. Therefore, we conclude that HE rather than NE reduces erythrocyte deformability and volume regulation, accompanied by an increase in the eryptotic response to oxidative stress. Simultaneously, this intervention depresses Gardos channel-modulated erythrocyte rheological functions. Results of this study provide further insight into erythrocyte senescence induced by HE.
Smith, JohnEric W.; Krings, Ben M.; Peterson, Timothy J.; Rountree, Jaden A.; Zak, Roksana B.; McAllister, Matthew J.
2017-01-01
The purpose of this study was to investigate the impact of ingesting an amino acid-electrolyte (AAE) beverage during upper body resistance exercise on transient muscle hypertrophy, exercise performance, markers of muscle damage, and recovery. Participants (n = 15) performed three sets of six repetitions—bench press, lat pull down, incline press, and seated row—followed by three sets of eight repetitions at 75% of the estimated 1 repetition maximum—triceps kickback, hammer curl, triceps push down, and preacher curl—with 90 s of rest between sets. The final set of the push down/preacher curl was performed to failure. Prior to and immediately post-exercise, as well as 24, 48, and 72 h post exercise, cross-sectional muscle thickness was measured. Blood samples were collected prior to exercise, as well as 24, 48, and 72 h post-exercise for serum creatine kinase (CK) analysis. No treatment effect was found for muscle cross-sectional area, repetitions to failure, or serum CK. A main effect (p < 0.001) was observed in the change in serum CK levels in the days following the resistance exercise session. The findings of this study suggest that the acute ingestion of a AAE beverage does not alter acute muscle thickness, performance, perceived soreness and weakness, or markers of muscle damage.
Chronic effect of static stretching on strength performance and basal serum IGF-1 levels.
Borges Bastos, Carmen L; Miranda, Humberto; Vale, Rodrigo Gomes de Souza; Portal, Maria de Nazaré; Gomes, M Thiago; Novaes, Jefferson da Silva; Winchester, Jason B
2013-09-01
Improving the process of how physical performance is enhanced is one of the main topics evaluated by physiologists. This process often involves athletes and nonathletic populations. The purpose of this study was to assess the chronic response to 10 weeks of static stretching exercises carried out before and during a strength training program for 8 exercises on an 8 repetition maximum (8RM) test performance, and basal serum insulinlike growth factor (IGF-1) levels. Thirty recreationally trained volunteers were randomly assigned to 1 of 3 training groups: (a) SBST (performed a warm-up with a static stretching protocol before each strength training session); (b) SDST (before each training set, a static stretching exercise was performed); and (c) OST (entire session was performed without any type of stretching exercise). Strength and IGF-1 levels were collected at the beginning (pretest) and end (posttest) of the entire experimental procedure. All the exercises showed a significant increase in muscle strength for the OST group. However, the results revealed a significant increase in the muscle strength for only a few exercises in the SBST (LP, LE) and SDST (LP) experimental conditions. Significant statistical differences were found between SBST and SDST for all the exercises in the OST experimental condition. Furthermore, the IGF-1 expression showed no significant differences in the intragroup analysis. However, the OST group showed higher values (p < 0.05) in the posttest when compared with those of the other groups (increased significantly only in the OST experimental condition). It has been concluded that, although all the groups showed an increase in muscular strength, the strength training performed without any type of stretching exercise, regardless of whether the stretching is performed before or during the lifting session, can more effectively increase muscle strength and basal serum IGF-1 levels. It was concluded that strength training, with or without the use of stretching exercises, increased muscular strength in the studied groups, and can induce an increase in IGF-1 levels.
DOT National Transportation Integrated Search
1982-05-01
Twelve healthy young men were evaluated in each of four experimental conditions involving the possible combinations of two exercise conditions given prior to performance testing (1 h of heavy exercise vs. no exercise) and two altitude conditions (gro...
Chaouachi, Mehdi; Granacher, Urs; Makhlouf, Issam; Hammami, Raouf; Behm, David G; Chaouachi, Anis
2017-03-01
The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players (13.9 ± 0.3 years) participated in an 8-week training program that either alternated individual balance (e.g., exercises on unstable surfaces) and plyometric (e.g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately >30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence.
Kovács, E; Sztruhár Jónásné, I; Karóczi, C K; Korpos, A; Gondos, T
2013-10-01
Exercise programs have important role in prevention of falls, but to date, there are conflicting findings about the effects of exercise programs on balance, functional performance and fall risk among cognitively impaired older adults. AIM. To investigate the effects of a multimodal exercise program on static and dynamic balance, and risk of falls in older adults with mild or moderate cognitive impairment. A randomized controlled study. A long-term care institute. Cognitively impaired individuals aged over 60 years. Eighty-six participants were randomized to an exercise group providing multimodal exercise program for 12 months or a control group which did not participate in any exercise program. The Performance Oriented Mobility Assessment scale, Timed Up and Go test, and incidence of falls were measured at baseline, at 6 months and at 12 months. There was a significant improvement in balance-related items of Performance Oriented Mobility Assessment scale in the exercise group both at 6 month and 12 month (P<0.0001, P=0.002; respectively). There was no statistically significant increase in gait-related items of Performance Oriented Mobility Assessment scale after the first 6-month treatment period (P=0.210), but in the second 6-month treatment period the POMA-G score improved significantly (P=0.001). There was no significant difference between groups regarding falls. Our results confirmed that a 12-month multimodal exercise program can improve the balance in cognitively impaired older adults. Based on our results, the multimodal exercise program may be a promising fall prevention exercise program for older adults with mild or moderate cognitive impairment improving static balance but it is supposed that more emphasis should be put on walking component of exercise program and environmental fall risk assessment.
Do Glucose and Caffeine Nasal Sprays Influence Exercise or Cognitive Performance?
De Pauw, Kevin; Roelands, Bart; Van Cutsem, Jeroen; Decroix, Lieselot; Valente, Angelica; Taehee, Kim; Lettan, Robert B; Carrillo, Andres E; Meeusen, Romain
2017-10-01
Nasal spray (NAS) containing caffeine (CAF) or glucose (GLUC) activates sensory(motor) cortices. To investigate the influence of CAF or GLUC NAS on exercise and cognitive performance. Eleven male subjects (age 22 ± 2 y) performed a maximal cycle test and 2 familiarization and 3 experimental trials. Each trial included a 30-s Wingate test and a 30-min time-trial (TT) performance test interspersed by 15 min of rest. Before and after each exercise test a Stroop task was conducted. Placebo NAS with or without CAF or GLUC was provided before each exercise session and at each completed 25% of the TT. Exercise-performance, physiological, and cognitive measures were obtained. Magnitude-based inferences determined the likelihood that NAS solutions would be beneficial, trivial, or negative to exercise-performance measures based on the smallest worthwhile effect. Physiological and cognitive measures were analyzed using (non)parametric tests (P < .05). GLUC NAS substantially increased the average power output during the TT (very likely beneficial: 98%). No further worthwhile exercise-performance enhancements were found for both substances. In addition, no significant differences in physiological and cognitive measures were observed. In line with mouth rinsing, GLUC was shown to substantially enhance endurance performance, probably due to the activation of the olfactory pathway and/or extra-oral sweet-taste receptors. GLUC NAS enhances endurance performance, which indicates a novel administration route. The higher activity in sensory brain cortices probably elicited the ergogenic effect. However, no further physiological and cognitive changes occurred, indicating that higher doses of substrates might be required.
Tanaka, Ryo; Ozawa, Junya; Kito, Nobuhiro; Moriyama, Hideki
2013-12-01
We performed a systematic review and meta-analysis of randomized controlled trials to investigate the differences in the efficacies between strengthening and aerobic exercises for pain relief in people with knee osteoarthritis. This search was applied to Medline, Cochrane Central Register of Controlled Trials, the Physiotherapy Evidence Database, and the Cumulative Index to Nursing and Allied Health Literature. All literature published from each source's earliest date to March 2013 was included. Trials comparing the effects of exercise intervention with those of either non-intervention or psycho-educational intervention were collected. Meta-analysis was performed for trials in which therapeutic exercise was carried out with more than three sessions per week up to eight weeks, for pain in people with knee osteoarthritis. All trials were categorised into three subgroups (non-weight-bearing strengthening exercise, weight-bearing strengthening exercise, and aerobic exercise). Subgroup analyses were also performed. Data from eight studies were integrated. Overall effect of exercise was significant with a large effect size (standardised mean difference (SMD): -0.94; 95% confidence interval -1.31 to -0.57). Subgroup analyses showed a larger SMD for non-weight-bearing strengthening exercise (-1.42 [-2.09 to -0.75]) compared with weight-bearing strengthening exercise (-0.70 [-1.05 to -0.35]), and aerobic exercise (-0.45 [-0.77 to -0.13]). Muscle strengthening exercises with or without weight-bearing and aerobic exercises are effective for pain relief in people with knee osteoarthritis. In particular, for pain relief by short-term exercise intervention, the most effective exercise among the three types is non-weight-bearing strengthening exercise.
Lack of effect of exercise time of day on acute energy intake in healthy men.
O'Donoghue K, J M; Fournier, Paul A; Guelfi, Kym J
2010-08-01
Although the manipulation of exercise and dietary intake to achieve successful weight loss has been extensively studied, it is unclear how the time of day that exercise is performed may affect subsequent energy intake. The purpose of the current study was to investigate the effect of an acute bout of exercise performed in the morning compared with an equivalent bout of exercise performed in the afternoon on short-term energy intake. Nine healthy male participants completed 3 trials: morning exercise (AM), afternoon exercise (PM), or control (no exercise; CON) in a randomized counterbalanced design. Exercise consisted of 45 min of treadmill running at 75% VO(2peak). Energy intake was assessed over a 26-hr period with the participants eating ad libitum from a standard assortment of food items of known quantity and composition. There was no significant difference in overall energy intake (M ± SD; CON 23,505 ± 6,938 kJ, AM 24,957 ± 5,607 kJ, PM 24,560 ± 5,988 kJ; p = .590) or macronutrient preferences during the 26-hr period examined between trials. Likewise, no differences in energy intake or macronutrient preferences were observed at any of the specific individual meal periods examined (i.e., breakfast, lunch, dinner) between trials. These results suggest that the time of day that exercise is performed does not significantly affect short-term energy intake in healthy men.
Duffield, Rob; Portus, Marc
2007-01-01
Objective To compare the effects of three types of full‐body compression garments (Skins, Adidas and Under Armour) on repeat‐sprint and throwing performance in cricket players. Methods Following familiarisation, 10 male cricket players performed four randomised exercise sessions (3 garments and a control). Each session involved a 30 min repeat‐sprint exercise protocol comprising 20 m sprints every minute, separated by submaximal exercise. Throwing tests included a pre‐exercise and a postexercise maximal distance test and accuracy throwing tests. During each session, measures of heart rate, skin temperature, change in body mass, rate of perceived exertion and perceived muscle soreness were recorded. Capillary blood samples were analysed before and after exercise for lactate, pH, O2 saturation and O2 partial pressure, and 24 h after exercise for creatine kinase (CK). Ratings of perceived muscle soreness were also obtained 24 h after exercise. Results No significant differences (p>0.05) were evident in repeat‐sprint performance (10 m, 20 m time or total submaximal distance covered) or throwing performance (maximum distance or accuracy). No significant differences (p>0.05) were observed in heart rate, body mass change or blood measures during exercise. Significant differences (p<0.05) were observed by way of higher mean skin temperature, lower 24 h postexercise CK values and lower 24 h postexercise ratings of muscle soreness when wearing compression garments. Analysis between respective brands of compression garments revealed no statistical differences (p>0.05). Conclusions No benefit was noted when wearing compression garments for repeat‐sprint or throwing performance; however, the use of the garments as a recovery tool, when worn after exercise, may be beneficial to reduce postexercise trauma and perceived muscle soreness. PMID:17341589
Michishita, Ryoma; Matsuda, Takuro; Kawakami, Shotaro; Tanaka, Satoshi; Kiyonaga, Akira; Tanaka, Hiroaki; Morito, Natsumi; Higaki, Yasuki
2017-11-06
This retrospective study evaluated the influence of the joint impact of habitual exercise and glycemic control on the incidence of chronic kidney disease (CKD) during a 6-year follow-up period in middle-aged and older males. The study population included 303 males without a history of cardiovascular disease, stroke, renal dysfunction, or dialysis treatment. Their lifestyle behaviors regarding exercise and physical activity were evaluated using a standardized self-administered questionnaire. The participants were divided into four categories according to the performance or non-performance of habitual exercise and the presence or absence of hyperglycemia. After 6 years, 32 subjects (10.6%) developed CKD (estimated glomerular filtration rate < 60 ml/min/1.73 m 2 and/or proteinuria). The cumulative incidence of CKD was significantly higher among subjects who did not perform habitual exercise and hyperglycemic subjects (log-rank test: p < 0.05, respectively). According to a Cox proportional hazards model, the hazard ratio (HR) for the incidence of CKD in subjects with a normal glucose tolerance (NGT) who did not perform habitual exercise (HR = 2.82, 95% confidence of interval (CI) = 1.07-7.36, p = 0.034) and that in hyperglycemic subjects who did not perform habitual exercise (HR = 5.89, 95% CI = 1.87-16.63, p = 0.003) were significantly higher in comparison to the subjects with a NGT who performed habitual exercise. These results suggest that the habitual exercise and good glycemic control and their combination were associated with the incidence of CKD.
Duffield, Rob; Portus, Marc
2007-07-01
To compare the effects of three types of full-body compression garments (Skins, Adidas and Under Armour) on repeat-sprint and throwing performance in cricket players. Following familiarisation, 10 male cricket players performed four randomised exercise sessions (3 garments and a control). Each session involved a 30 min repeat-sprint exercise protocol comprising 20 m sprints every minute, separated by submaximal exercise. Throwing tests included a pre-exercise and a postexercise maximal distance test and accuracy throwing tests. During each session, measures of heart rate, skin temperature, change in body mass, rate of perceived exertion and perceived muscle soreness were recorded. Capillary blood samples were analysed before and after exercise for lactate, pH, O(2) saturation and O(2) partial pressure, and 24 h after exercise for creatine kinase (CK). Ratings of perceived muscle soreness were also obtained 24 h after exercise. No significant differences (p>0.05) were evident in repeat-sprint performance (10 m, 20 m time or total submaximal distance covered) or throwing performance (maximum distance or accuracy). No significant differences (p>0.05) were observed in heart rate, body mass change or blood measures during exercise. Significant differences (p<0.05) were observed by way of higher mean skin temperature, lower 24 h postexercise CK values and lower 24 h postexercise ratings of muscle soreness when wearing compression garments. Analysis between respective brands of compression garments revealed no statistical differences (p>0.05). No benefit was noted when wearing compression garments for repeat-sprint or throwing performance; however, the use of the garments as a recovery tool, when worn after exercise, may be beneficial to reduce postexercise trauma and perceived muscle soreness.
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.
Farias, Déborah de Araújo; Willardson, Jeffrey M; Paz, Gabriel A; Bezerra, Ewertton de S; Miranda, Humberto
2017-07-01
Farias, DdA, Willardson, JM, Paz, GA, Bezerra, EdS, and Miranda, H. Maximal strength performance and muscle activation for the bench press and triceps extension exercises adopting dumbbell, barbell and machine modalities over multiple sets. J Strength Cond Res 31(7): 1879-1887, 2017-The purpose of this study was to investigate muscle activation, total repetitions, and training volume for 3 bench press (BP) exercise modes (Smith machine [SMBP], barbell [BBP], and dumbbell [DBP]) that were followed by a triceps extension (TE) exercise. Nineteen trained men performed 3 testing protocols in random order, which included: (P1) SMBP + TE; (P2) BBP + TE; and (P3) DBP + TE. Each protocol involved 4 sets with a 10-repetition maximum (RM) load, immediately followed by a TE exercise that was also performed for 4 sets with a 10RM load. A 2-minute rest interval was adopted between sets and exercises. Surface electromyographic activity was assessed for the pectoralis major (PM), anterior deltoid (AD), biceps brachii (BB), and triceps brachii (TB). The results indicated that significantly higher total repetitions were achieved for the DBP (31.2 ± 3.2) vs. the BBP (27.8 ± 4.8). For the TE, significantly greater volume was achieved when this exercise was performed after the BBP (1,204.4 ± 249.4 kg) and DBP (1,216.8 ± 287.5 kg) vs. the SMBP (1,097.5 ± 193 kg). The DBP elicited significantly greater PM activity vs. the BBP. The SMBP elicited significantly greater AD activity vs. the BBP and DBP. During the different BP modes, the SMBP and BBP elicited significantly greater TB activity vs. the DBP. However, the DBP elicited significantly greater BB activity vs. the SMBP and BBP, respectively. During the succeeding TE exercise, significantly greater activity of the TB was observed when this exercise was performed after the BBP vs. the SMBP and DBP. Therefore, it seems that the variation in BP modes does influence both repetition performance and muscle activation patterns during the TE when these exercises are performed in succession.
Liu, Chiung-ju; Xu, Huiping; Keith, NiCole R; Clark, Daniel O
2017-01-01
Background Resistance exercise is effective to increase muscle strength for older adults; however, its effect on the outcome of activities of daily living is often limited. The purpose of this study was to examine whether 3-Step Workout for Life (which combines resistance exercise, functional exercise, and activities of daily living exercise) would be more beneficial than resistance exercise alone. Methods A single-blind randomized controlled trial was conducted. Fifty-two inactive, community-dwelling older adults (mean age =73 years) with muscle weakness and difficulty in activities of daily living were randomized to receive 3-Step Workout for Life or resistance exercise only. Participants in the 3-Step Workout for Life Group performed functional movements and selected activities of daily living at home in addition to resistance exercise. Participants in the Resistance Exercise Only Group performed resistance exercise only. Both groups were comparable in exercise intensity (moderate), duration (50–60 minutes each time for 10 weeks), and frequency (three times a week). Assessment of Motor and Process Skills, a standard performance test on activities of daily living, was administered at baseline, postintervention, and 6 months after intervention completion. Results At postintervention, the 3-Step Workout for Life Group showed improvement on the outcome measure (mean change from baseline =0.29, P=0.02), but the improvement was not greater than the Resistance Exercise Only Group (group mean difference =0.24, P=0.13). However, the Resistance Exercise Only Group showed a significant decline (mean change from baseline =−0.25, P=0.01) 6 months after the intervention completion. Meanwhile, the superior effect of 3-Step Workout for Life was observed (group mean difference =0.37, P<0.01). Conclusion Compared to resistance exercise alone, 3-Step Workout for Life improves the performance of activities of daily living and attenuates the disablement process in older adults. PMID:28769559
Functional training improves club head speed and functional fitness in older golfers.
Thompson, Christian J; Cobb, Karen Myers; Blackwell, John
2007-02-01
Functional training programs have been used in a variety of rehabilitation settings with documented success. Based on that success, the concept of functional training has gained popularity in applied fitness settings to enhance sport performance. However, there has been little or no research studying the efficacy of functional training programs on the improvement of sport performance or functional fitness. Thus, it was the purpose of this study to determine the effect of a progressive functional training program on club head speed and functional fitness in older male golfers. Eighteen male golfers (age: 70.7 +/- 9.1 [SD] years) were randomly assigned to an exercise (N = 11) or control (N = 7) group. The exercise group participated in an 8-week progressive functional training program including flexibility exercises, core stability exercises, balance exercises, and resistance exercises. Pre- and postmeasurements included club head speed of a driver by radar (exercise and Control) and Fullerton Senior Fitness Test measurements (exercise only). One-way analysis of covariance was performed on club head speed measurements using pretest measurements as the covariate. Paired t-tests were performed to analyze Senior Fitness Test variables. After the intervention, maximal club head speed increased in the exercise group (127.3 +/- 13.4 to 133.6 +/- 14.2 km x hr(-1)) compared with the control group (134.5 +/- 14.6 to 133.3 +/- 11.2 km x hr(-1); p < 0.05). Additionally, improvements (p < 0.05) were detected for most Senior Fitness Test variables in the exercise group. In summary, this functional training program resulted in significant improvements in club head speed and several components of functional fitness. Future research should continue to examine the effect of functional training programs on sport performance and functional fitness in older adults.
Christensen, Peter M.; Bangsbo, Jens
2016-01-01
Athletes in intense endurance sports (e.g., 4000-m track cycling) often perform maximally (~4 min) twice a day due to qualifying and finals being placed on the same day. The purpose of the present study was to evaluate repeated performance on the same day in a competitive setting (part A) and the influence from prior intense exercise on subsequent performance and physiological response to moderate and maximal exercise with and without the use of cold water immersion (CWI) in recovery (part B). In part A, performance times during eight World championships for male track cyclists were extracted from the qualifying and final races in 4000-m individual pursuit. In part B, twelve trained cyclists with an average (±SD) ⩒O2-peak of 67 ± 5 mL/min/kg performed a protocol mimicking a qualifying race (QUAL) followed 3 h later by a performance test (PT) with each exercise period encompassing intense exercise for ~4 min preceded by an identical warm-up period in both a control setting (CON) and using cold water immersion in recovery (CWI; 15 min at 15°C). Performance was lowered (P < 0.001) from qualification to finals (259 ± 3 vs. 261 ± 3 s) for the track cyclists during World championships in part A. In part B, mean power in PT was not different in CWI relative to CON (406 ± 43 vs. 405 ± 38 W). Peak ⩒O2 (5.04 ± 0.50 vs. 5.00 ± 0.49 L/min) and blood lactate (13 ± 3 vs. 14 ± 3 mmol/L) did not differ between QUAL and PT and cycling economy and potassium handling was not impaired by prior intense exercise. In conclusion, performance is reduced with repeated maximal exercise in world-class track cyclists during 4000-m individual pursuit lasting ~4 min, however prior intense exercise do not appear to impair peak ⩒O2, peak lactate, cycling economy, or potassium handling in trained cyclists and CWI in recovery does not improve subsequent performance. PMID:27445857
Neural Contributions to Muscle Fatigue: From the Brain to the Muscle and Back Again
Taylor, Janet L.; Amann, Markus; Duchateau, Jacques; Meeusen, Romain; Rice, Charles L.
2016-01-01
During exercise, there is a progressive reduction in the ability to produce muscle forces. Processes within the nervous system, as well as within the muscles contribute to this fatigue. In addition to impaired function of the motor system, sensations associated with fatigue, and impairment of homeostasis can contribute to impairment of performance during exercise. This review discusses some of the neural changes that accompany exercise and the development of fatigue. The role of brain monoaminergic neurotransmitter systems in whole-body endurance performance is discussed, particularly with regard to exercise in hot environments. Next, fatigue-related alterations in the neuromuscular pathway are discussed in terms of changes in motor unit firing, motoneuron excitability and motor cortical excitability. These changes have mostly been investigated during single-limb isometric contractions. Finally, the small-diameter muscle afferents that increase firing with exercise and fatigue are discussed. These afferents have roles in cardiovascular and respiratory responses to exercise, and in impairment of exercise performance through interaction with the motor pathway, as well as providing sensations of muscle discomfort. Thus, changes at all levels of the nervous system including the brain, spinal cord, motor output, sensory input and autonomic function occur during exercise and fatigue. The mix of influences and the importance of their contribution varies with the type of exercise being performed. PMID:27003703
Yanagisawa, O; Otsuka, S; Fukubayashi, T
2014-02-01
To evaluate the effects of cooling between exercise sessions on intramuscular water movement and muscle performance, the lower extremities of nine untrained men were assigned to either a cooling protocol (20-min water immersion, 15 °C) or a noncooling protocol. Each subject performed two exercise sessions involving maximal concentric knee extension and flexion (three repetitions, 60°/s; followed by 50 repetitions, 180°/s). The peak torque at 60°/s and total work, mean power, and decrease rate of torque value at 180°/s were evaluated. Axial magnetic resonance diffusion-weighted images of the mid-thigh were obtained before and after each exercise session. Apparent diffusion coefficient (ADC) values for the quadriceps and hamstrings were calculated for evaluating intramuscular water movement. Both groups exhibited significantly increased ADC values for the quadriceps and hamstrings after each exercise session. These ADC values returned to the pre-exercise level after water immersion. No significant difference was observed in muscle performance from first exercise session to the next in either group, except for increased total work and mean power in knee flexion in the cooled group. Cooling intervention between exercise sessions decreased exercise-induced elevation of intramuscular water movement and had some beneficial effects on muscle endurance of knee flexors, but not knee extensors. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
West, Daniel W. D.; Abou Sawan, Sidney; Mazzulla, Michael; Williamson, Eric; Moore, Daniel R.
2017-01-01
No study has concurrently measured changes in free-living whole body protein metabolism and exercise performance during recovery from an acute bout of resistance exercise. We aimed to determine if whey protein ingestion enhances whole body net protein balance and recovery of exercise performance during overnight (10 h) and 24 h recovery after whole body resistance exercise in trained men. In a double-blind crossover design, 12 trained men (76 ± 8 kg, 24 ± 4 years old, 14% ± 5% body fat; means ± standard deviation (SD)) performed resistance exercise in the evening prior to consuming either 25 g of whey protein (PRO; MuscleTech 100% Whey) or an energy-matched placebo (CHO) immediately post-exercise (0 h), and again the following morning (~10 h of recovery). A third randomized trial, completed by the same participants, involving no exercise and no supplement served as a rested control trial (Rest). Participants ingested [15N]glycine to determine whole body protein kinetics and net protein balance over 10 and 24 h of recovery. Performance was assessed pre-exercise and at 0, 10, and 24 h of recovery using a battery of tests. Net protein balance tended to improve in PRO (P = 0.064; effect size (ES) = 0.61, PRO vs. CHO) during overnight recovery. Over 24 h, net balance was enhanced in PRO (P = 0.036) but not in CHO (P = 0.84; ES = 0.69, PRO vs. CHO), which was mediated primarily by a reduction in protein breakdown (PRO < CHO; P < 0.01. Exercise decreased repetitions to failure (REP), maximal strength (MVC), peak and mean power, and countermovement jump performance (CMJ) at 0 h (all P < 0.05 vs. Pre). At 10 h, there were small-to-moderate effects for enhanced recovery of the MVC (ES = 0.56), mean power (ES = 0.49), and CMJ variables (ES: 0.27–0.49) in PRO. At 24 h, protein supplementation improved MVC (ES = 0.76), REP (ES = 0.44), and peak power (ES = 0.55). In conclusion, whey protein supplementation enhances whole body anabolism, and may improve acute recovery of exercise performance after a strenuous bout of resistance exercise. PMID:28696380
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.
Kang, Taewook; Lee, Jaeseok; Seo, Junghoon; Han, Dongwook
2017-04-01
[Purpose] The purpose of this research is to investigate the effect of the method of bridge exercise on the change of rectus abdominis muscle and the muscle activity of paraspinal muscles while doing treadmill walking with high heels. [Subjects and Methods] The subjects of this research are healthy female students consisting of 10 persons performing bridge exercises in a supine group, 10 persons performing bridge exercises in a prone group, and 10 persons in a control group while in S university in Busan. Bridge exercise in supine position is performed in hook lying position. Bridge exercise in prone position is plank exercise in prostrate position. To measure the strength of rectus abdominis muscle, maintaining times of the posture was used. To measure the muscle activity of paraspinal muscles, EMG (4D-MT & EMD-11, Relive, Korea) was used. [Results] The strength of rectus abdominis muscle of both bridge exercises in the supine group and bridge exercises in the prone group increases significantly after exercise. The muscle activity of paraspinal muscle such as thoracic parts and lumbar parts in bridge exercises in the prone group decreases statistically while walking on a treadmill with high heels. Muscle activity of thoracic parts paraspinal muscle and bridge exercises in the supine group decreased significantly. [Conclusion] According to this study, we noticed that bridge exercise in a prone position is desirable for women who prefer wearing high heels as a back pain prevention exercise method.
Zaitsu, Kosuke; Nishimura, Yuki; Matsuguma, Hiroyuki; Higuchi, Shigekazu
2015-10-01
We examined the effects of an exergame intervention on exercise performance, as well as the influence of players' personality traits on the effects of the intervention. In total, 16 elderly persons (>65 years old) participated in the study for 12 weeks. Participants were required to complete the Big Five Scale. We measured the number of times that the sit-to-stand exercise was performed during the interventions with and without exergames. We compared the average number of times that the sit-to-stand exercise was performed per day in each of the two conditions. The average number of times that exercise was undertaken with exergame use was greater than that without exergame use; however, no significant difference was found. The difference between the average number of times that exercise occurred with and without exergame use was positively correlated with neuroticism, negatively correlated with extraversion, and not associated with conscientiousness. The intervention comprising the use of exergames has a positive motivational influence among less extraverted elderly persons.
Matsumoto, M; Hanrath, P; Kremer, P; Tams, C; Langenstein, B A; Schlüter, M; Weiter, R; Bleifeld, W
1982-01-01
In order to evaluate left ventricular function during dynamic exercise transoesophageal M-mode recordings of the left ventricle were carried out with a newly developed transducer gastroscope system. Twelve healthy subjects performed a graded supine bicycle exercise test. Stable and good quality images of the left ventricle at rest and during exercise at different steps up to a maximum workload of 100 watts were obtained in all patients. Isotonic maximum exercise resulted in a significant increase in fractional shortening of the left ventricle, peak shortening rate, and peak lengthening rate of the left ventricular minor axis. Left ventricular end-diastolic dimension decreased significantly. With increasing workload the pressure rate product increased significantly. It is concluded that transoesophageal M-mode echocardiography is a useful method of evaluating left ventricular performance during dynamic exercise. Images PMID:7082515
Exercise for women receiving adjuvant therapy for breast cancer.
Furmaniak, Anna C; Menig, Matthias; Markes, Martina H
2016-09-21
A huge clinical research database on adjuvant cancer treatment has verified improvements in breast cancer outcomes such as recurrence and mortality rates. On the other hand, adjuvant and neoadjuvant therapy with chemotherapy and radiotherapy impacts on quality of life due to substantial short- and long-term side effects. A number of studies have evaluated the effect of exercise interventions on those side effects. This is an updated version of the original Cochrane review published in 2006. The original review identified some benefits of physical activity on physical fitness and the resulting capacity for performing activities of daily life. It also identified a lack of evidence for other outcomes, providing clear justification for an updated review. To assess the effect of aerobic or resistance exercise interventions during adjuvant treatment for breast cancer on treatment-related side effects such as physical deterioration, fatigue, diminished quality of life, depression, and cognitive dysfunction. We carried out an updated search in the Cochrane Breast Cancer Group Specialised Register (30 March 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2, 2015), MEDLINE (1966 to 30 March 2015), and EMBASE (1966 to 30 March 2015). We did not update the original searches in CINAHL (1982 to 2004), SPORTDiscus (1975 to 2004), PsycINFO (1872 to 2003), SIGLE (1880 to 2004), and ProQuest Digital Dissertations (1861 to 2004). We searched the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov for ongoing trials on 30 March 2015. We screened references in relevant reviews and published clinical trials. We included randomised controlled trials that examined aerobic or resistance exercise or both in women undergoing adjuvant treatment for breast cancer. Published and unpublished trials were eligible. Two review authors independently performed data extraction, assessed trials, and graded the methodological quality using Cochrane's 'Risk of bias' tool. Any disagreements were resolved through discussion or by consulting the third review author. We entered data into Review Manager for analysis. For outcomes assessed with a variety of instruments, we used the standardised mean difference (SMD) as a summary statistic for meta-analysis; for those assessed with the same instrument, we used the mean difference (MD). For this 2015 update we included a total of 32 studies with 2626 randomised women, 8 studies from the original search and 24 studies from the updated search. We found evidence that physical exercise during adjuvant treatment for breast cancer probably improves physical fitness (SMD 0.42, 95% confidence interval (CI) 0.25 to 0.59; 15 studies; 1310 women; moderate-quality evidence) and slightly reduces fatigue (SMD -0.28, 95% CI -0.41 to -0.16; 19 studies; 1698 women; moderate-quality evidence). Exercise may lead to little or no improvement in health-related quality of life (MD 1.10, 95% CI -5.28 to 7.48; 1 study; 68 women; low-quality evidence), a slight improvement in cancer site-specific quality of life (MD 4.24, 95% CI -1.81 to 10.29; 4 studies; 262 women; low-quality evidence), and an improvement in cognitive function (MD -11.55, 95% CI -22.06 to -1.05; 2 studies; 213 women; low-quality evidence). Exercise probably leads to little or no difference in cancer-specific quality of life (SMD 0.12, 95% CI 0.00 to 0.25; 12 studies; 1012 women; moderate-quality evidence) and little or no difference in depression (SMD -0.15, 95% CI -0.30 to 0.01; 5 studies; 674 women; moderate-quality evidence). Evidence for other outcomes ranged from low to moderate quality. Seven trials reported a very small number of adverse events. Exercise during adjuvant treatment for breast cancer can be regarded as a supportive self care intervention that probably results in less fatigue, improved physical fitness, and little or no difference in cancer-specific quality of life and depression. Exercise may also slightly improve cancer site-specific quality of life and cognitive function, while it may result in little or no difference in health-related quality of life. This review is based on trials with a considerable degree of clinical heterogeneity regarding adjuvant cancer treatments and exercise interventions. Due to the difficulty of blinding exercise trials, all included trials were at high risk for performance bias. Furthermore, the majority of trials were at high risk for detection bias, largely due to most outcomes being self reported.The findings of the updated review have enabled us to make a more precise conclusion that both aerobic and resistance exercise can be regarded as beneficial for individuals with adjuvant therapy-related side effects. Further research is required to determine the optimal type, intensity, and timing of an exercise intervention. Furthermore, long-term evaluation is required due to possible long-term side effects of adjuvant treatment.
Duncan, Michael J; Chan, Cheryl K Y; Clarke, Neil D; Cox, Martin; Smith, Mike
2017-03-01
This study examined the effects of changes in physiological and psychological arousal on badminton short-serve performance in competitive and practice climates. Twenty competitive badminton players (10 males and 10 females) volunteered to participate in the study following ethics approval. After familiarisation, badminton short-serve performance was measured at rest, mid-way through and at the end of a badminton-specific exercise protocol in two conditions; competition vs. practice. Ratings of cognitive and somatic anxiety were assessed at three time points prior to badminton short-serve performance using the Mental Readiness Form 3. Heart rate and rating of perceived exertion (RPE) were assessed during the exercise protocol. Results indicated that better short-serve performance was evident in practice compared to competition (P = .034). RPE values were significantly higher in the competition condition compared to practice (P = .007). Cognitive anxiety intensity was significantly lower post-exercise in the practice condition compared to competition (P = .001). Cognitive anxiety direction showed greater debilitation post-exercise in the competition condition compared to practice (P = .01). Somatic anxiety intensity increased from pre-, to mid- to post-exercise (P = .001) irrespective of condition. This study suggests that badminton serve performance is negatively affected when physiological arousal, via badminton-specific exercise, and cognitive anxiety, via perceived competition, are high.
From rest to stressed: endothelin-1 levels in young healthy smokers and non-smokers.
Cooke, Alexandra B; Toli, Eirini; Gomez, Yessica-Haydee; Mutter, Andrew F; Eisenberg, Mark J; Mantzoros, Christos S; Daskalopoulou, Stella S
2015-09-01
Endothelin-1 (ET-1) is a potent vasoconstrictor produced by vascular endothelial cells, and a known marker of endothelial dysfunction. However, the acute and chronic effects of smoking and nicotine gum on the ET-1 response to acute physical stress in young healthy smokers have not been investigated. Healthy smokers (n=35) and non-smokers (n=35) underwent an exercise test to exhaustion (maximal oxygen consumption) on a treadmill. Smokers were assessed a) after 12h smoking abstinence (termed chronic smoking), b) immediately after smoking one cigarette (termed acute smoking), and c) immediately after chewing nicotine gum. Blood was drawn immediately pre-exercise, and 3 minutes post-exercise. During exercise, cardiorespiratory parameters were obtained breath-by-breath using an automated metabolic cart. Plasma ET-1 levels were quantified using enzyme-linked immunosorbent-assay. The above protocol was designed to incorporate exercise as a vascular stressor to reveal changes that would not be detected at rest. Mean age was 28.6±7.2 years and body mass index (BMI) was 23.6±3.2 kg/m(2). Post-exercise ET-1 levels were significantly lower than pre-exercise levels in non-smokers (P<0.001) and smokers under all three conditions (P=0.005, P<0.001, P=0.001, respectively). There were no differences in post-exercise ET-1 levels between non-smokers and smokers under all three conditions, however the absolute and relative decrease in ET-1 levels was significantly smaller in chronic smokers compared with non-smokers (P=0.007 and P=0.004). Chronic smokers had a significantly lower exercise-induced change in tidal volume (P=0.050), fraction of expired CO2 (P=0.021), oxygen consumption (P=0.005), carbon dioxide elimination (P=0.004) and peak expiratory flow (P=0.003) compared with non-smokers. Furthermore, the decrease in ET-1 observed in non-smokers in response to exercise was significantly associated with exercise induced-changes in inspiratory time, time for a tidal volume cycle, respiratory frequency, inspired minute ventilation and peak inspiratory flow. An acute decrease of circulating ET-1 in response to acute maximal exercise in young healthy individuals was noted. Chronic smokers had a significantly diminished decrease in ET-1 compared with non-smokers, however there were no significant differences in the ET-1 response between smokers under the three smoking conditions. Smokers were not able to achieve the same exercise-induced changes in cardiorespiratory parameters as non-smokers. By incorporating exercise as a vascular stressor in our study, we have taken a novel approach to provide evidence of an altered ET-1 and cardiorespiratory response that would not otherwise be observed at rest in young active healthy smokers. Copyright © 2015 Elsevier Inc. All rights reserved.
Older persons' experiences of a home-based exercise program with behavioral change support.
Arkkukangas, Marina; Sundler, Annelie J; Söderlund, Anne; Eriksson, Staffan; Johansson, Ann-Christin
2017-12-01
It is a challenge to promote exercise among older persons. Knowledge is needed regarding the maintenance of exercise aiming at preventing falls and promoting health and well-being in older persons. This descriptive study used a qualitative inductive approach to describe older persons' experiences of a fall-preventive, home-based exercise program with support for behavioral change. Semi-structured interviews were conducted with 12 elderly persons aged 75 years or older, and a qualitative content analysis was performed. Four categories emerged: facilitators of performing exercise in everyday life, the importance of support, perceived gains from exercise, and the existential aspects of exercise. With support from physiotherapists (PTs), home-based exercise can be adapted to individual circumstances in a meaningful way. Including exercises in everyday life and daily routines could support the experience of being stronger, result in better physical functioning, and give hope for an extended active life in old age.
Evaluation of different time schedules in training with the Da Vinci simulator.
Güldner, C; Orth, A; Dworschak, P; Diogo, I; Mandapathil, M; Teymoortash, A; Walliczek-Dworschak, U
2017-10-01
This prospective study analyzed the effect of different time schedules in training on the main performance outcomes: overall score, time to complete, and economy of motion. The study was performed on the da Vinci Skills Simulator from December 2014 to April 2016. Forty robotic novices were randomized into two groups of 20 participants, which trained in the same three exercises but with different intervals between their training sessions. Each group performed training in Peg Board 1 in their first week, Match Board 2 in their second week, and Ring and Rail 2 in their third week. On their last day, Needle Targeting and Energy Dissection 2, for which no previous training had been received, were performed. Regarding the different training intervals, group 1 trained each exercise six times in a row once a week. Group 2 performed their training once a day for 5 days. Technical performance parameters were recorded by the Mimics simulator software for further analysis. In addition, the participants were asked to fill out a questionnaire concerning the robotics training. Group 2 performed significantly better compared to group 1 in the main metrics in the more advanced exercises. For the easier exercises, the training frequency did not lead to significant differences in performance outcome. A significant skills gain was seen between the first and last training sessions for all exercises in both groups. Performance in the final exercise NT was significantly better in group 2 than group 1. Regarding ED 2, no difference was found between the two groups. As the training of group 2 led to significantly better outcomes, we suggest that, especially for advanced exercises, it seems to be more favorable to perform training every day for a short period than to train once a week six times in a row.
The Limits of Exercise Physiology: From Performance to Health.
Gabriel, Brendan M; Zierath, Juleen R
2017-05-02
Many of the established positive health benefits of exercise have been documented by historical discoveries in the field of exercise physiology. These investigations often assess limits: the limits of performance, or the limits of exercise-induced health benefits. Indeed, several key findings have been informed by studying highly trained athletes, in addition to healthy or unhealthy people. Recent progress has been made in regard to skeletal muscle metabolism and personalized exercise regimes. In this perspective, we review some of the historical milestones of exercise physiology, discuss how these inform contemporary knowledge, and speculate on future questions. Copyright © 2017 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mundie, T.G.
This study was designed the effects of exercise performed on animals already injured with E. coli endotoxin. This would tell us whether exercise makes the lung injury worse. It would also tell us how much exercise performance is impaired. These studies were designed to give further insights into the underlying causes of acute lung injury. Premature termination of the study prevented completion of the research project. It appeared from the limited experimentation conducted that maximal exercise was impaired by endotoxin-induced lung injury. Conclusions regarding exacerbation of endotoxin-induced lung injury cannot be made.... Acute lung injury, Maximal exercise, Endotoxin.
Nutrition and Supplementation Considerations to Limit Endotoxemia When Exercising in the Heat
Guy, Joshua H.
2018-01-01
Exercise-induced heat production is further elevated by exercise performed in hot conditions and this can subsequently impact inflammation, and gastrointestinal (GI) health. Implementing nutrition and supplementation strategies under these conditions may support the hyperthermic response, the systemic inflammatory response, GI permeability and integrity, and exercise performance. Therefore, the aim of this brief review is to explore athletes’ inflammatory response of two key biomarkers, lipopolysaccharide (LPS), and interleukin-6 (IL-6), and provide nutrition and supplementation recommendations when exercising in hot conditions. There is emerging evidence that probiotics, glutamine, and vitamin C can preserve GI integrity, which may improve performance during exercise in the heat. Glucose rich food when consumed with water, before and during exercise in the heat, also appear to limit endotoxemia, preserve GI integrity, and reduce the incidence of GI disturbances compared with water alone. The use of non-steroidal anti-inflammatory drugs (NSAIDs) may compromise GI integrity and this may result in greater leakage of endotoxins during long duration exercise in the heat. Further work is required to elucidate the impact of nutrition and supplementation strategies, in particular the use of NSAIDs, when exercising in the heat.
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.
Nutrition and Supplementation Considerations to Limit Endotoxemia When Exercising in the Heat.
Guy, Joshua H; Vincent, Grace E
2018-02-06
Exercise-induced heat production is further elevated by exercise performed in hot conditions and this can subsequently impact inflammation, and gastrointestinal (GI) health. Implementing nutrition and supplementation strategies under these conditions may support the hyperthermic response, the systemic inflammatory response, GI permeability and integrity, and exercise performance. Therefore, the aim of this brief review is to explore athletes' inflammatory response of two key biomarkers, lipopolysaccharide (LPS), and interleukin-6 (IL-6), and provide nutrition and supplementation recommendations when exercising in hot conditions. There is emerging evidence that probiotics, glutamine, and vitamin C can preserve GI integrity, which may improve performance during exercise in the heat. Glucose rich food when consumed with water, before and during exercise in the heat, also appear to limit endotoxemia, preserve GI integrity, and reduce the incidence of GI disturbances compared with water alone. The use of non-steroidal anti-inflammatory drugs (NSAIDs) may compromise GI integrity and this may result in greater leakage of endotoxins during long duration exercise in the heat. Further work is required to elucidate the impact of nutrition and supplementation strategies, in particular the use of NSAIDs, when exercising in the heat.
Keser, Ilke; Kirdi, Nuray; Meric, Aydin; Kurne, Asli Tuncer; Karabudak, Rana
2013-01-01
This study compared trunk exercises based on the Bobath concept with routine neurorehabilitation approaches in multiple sclerosis (MS). Bobath and routine neurorehabilitation exercises groups were evaluated. MS cases were divided into two groups. Both groups joined a 3 d/wk rehabilitation program for 8 wk. The experimental group performed trunk exercises based on the Bobath concept, and the control group performed routine neurorehabilitation exercises. Additionally, both groups performed balance and coordination exercises. All patients were evaluated with the Trunk Impairment Scale (TIS), Berg Balance Scale (BBS), International Cooperative Ataxia Rating Scale (ICARS), and Multiple Sclerosis Functional Composite (MSFC) before and after the physiotherapy program. In group analysis, TIS, BBS, ICARS, and MSFC scores and strength of abdominal muscles were significantly different after treatment in both groups (p < 0.05). When the groups were compared, no significant differences were found in any parameters (p > 0.05). Although trunk exercises based on the Bobath concept are rarely applied in MS rehabilitation, the results of this study show that they are as effective as routine neurorehabilitation exercises. Therefore, trunk exercises based on the Bobath concept can be beneficial in MS rehabilitation programs.
Schneider, Stefan; Abeln, Vera; Popova, Julia; Fomina, Elena; Jacubowski, Amrei; Meeusen, Romain; Strüder, Heiko K
2013-01-01
With respect to the plans of national and internationals space agencies to send people to Mars or Moon, long-term isolation studies are performed to learn about the psycho-physiological and psycho-social limitations of such missions. From June 3rd 2010 to November 4th 2011 six participants lived under totally isolated and confined conditions in the MARS500 habitat located in Moscow. Despite the possibility to mimic the condition of space travel, this study allowed for experimental conditions under very reliable and traceable conditions. As exercise is widely discussed to have a positive impact on neuro-cognitive performance, this study aimed to test the effect of different exercise protocol (endurance/strength orientated) on brain cortical activity and cognitive performance. Brain cortical activity was recorded using a 16 channel EEG before and after exercise across the 520 days of confinement. Cognitive performance was assessed using three commercially available brain games. Following the theory of transient hypofrontality, results show a significant decrease of frontal brain cortical activity after exercise (p<.05) which was most expressed after endurance orientated protocols. Cognitive performance was improved following running sessions on an active treadmill (p<.05). Results let us assume that not exercise per se acts as a neuro-enhancer. It is more likely that a general defocusing caused by an immersion into exercise is necessary to improve cognitive performance. Copyright © 2012 Elsevier B.V. All rights reserved.
Inhaled whole exhaust and its effect on exercise performance and vascular function.
Cutrufello, Paul T; Rundell, Kenneth W; Smoliga, James M; Stylianides, Georgios A
2011-09-01
Internal combustion engines are a major source of particulate matter (PM) which has been shown to result in vasoconstriction, yet no present study to our knowledge has investigated the effect of exhaust emissions on both exercise performance and the vasculature. To examine the effect of freshly generated whole exhaust on exercise performance, pulmonary arterial pressure (PP), and flow-mediated vasodilation (FMD) of the brachial artery. Sixteen male, collegiate athletes (age: 20.8±1.28 years) were randomly assigned to submaximal exercise for 20 min followed by a 6 min maximal work accumulation exercise test in either high PM (HPM) or low PM (LPM) conditions on two consecutive days. After a 7-day washout period, subjects completed identical exercise trials in the alternate condition. HPM conditions were generated from a 4-cycle gasoline engine. The participants' PP and FMD were assessed before and after each exercise trial by tricuspid regurgitant velocity and brachial artery imaging, respectively. Total work (LPM: 108.0±14.8 kJ; HPM: 104.9±15.2 kJ, p=0.019) and FMD (LPM: 8.17±6.41%; HPM: 6.59±2.53%; p=0.034) significantly decreased in HPM while PP was significantly increased (LPM: 16.9±1.13 mmHg; HPM: 17.9±1.70 mmHg; p=0.004). A significant correlation was identified between the change in exercise performance and the change in FMD (r=0.494; p=0.026) after the first HPM trial. Exercise performance declined in HPM conditions in part due to impaired vasodilation in the peripheral vasculature.
Polyphenol supplementation: benefits for exercise performance or oxidative stress?
Myburgh, Kathryn H
2014-05-01
Supplement use among athletes is widespread, including non-traditional and biological compounds. Despite increasing research, a comprehensive and critical review on polyphenol supplementation and exercise is still lacking. This review is relevant for researchers directly involved in the topic, as well as those with a broad interest in athletic performance enhancement and sports nutrition. The purpose of this review is to present background information on groups of polyphenols and their derivatives because their differing chemical structures influence mechanisms of action; to discuss the potential of plant, fruit and vegetable-based biological supplements, high in polyphenol content, to affect exercise performance and biomarkers of oxidative stress and exercise-induced muscle damage; and to critically discuss the exercise studies and biomarkers used. Subjects in the studies reviewed were either sedentary, healthy individuals, or active, recreationally trained or well-trained athletes. Polyphenol supplementation in exercise studies included mainly extracts (multicomponent or purified), juices, infusions or an increased intake of polyphenol-rich foods. This review includes details of supplement doses and exercise test protocols. Many studies considered only the performance or one or two selected biomarkers of antioxidant capacity instead of a comprehensive choice of biomarkers to assess damage to lipids or proteins. Evidence is insufficient to make recommendations for or against the use of polyphenol supplementation (neither specific polyphenols nor specific doses) for either recreational, competitive or elite athletes. Polyphenols have multiple biological effects, and future exercise studies must be designed appropriately and specifically to determine physiological interactions between exercise and the selected supplement, rather than considering performance alone.
"Nutraceuticals" in relation to human skeletal muscle and exercise.
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.
NASA Technical Reports Server (NTRS)
Lee, Stuart M. C.; Stenger, Michael B.; Laurie, Steven S.; Ploutz-Snyder, Lori L.; Platts, Steven H.
2015-01-01
More than 60% of US astronauts participating in Mir and early International Space Station missions (greater than 5 months) were unable to complete a 10-min 80 deg head-up tilt test on landing day. This high incidence of post-spaceflight orthostatic intolerance may be related to limitations of the inflight exercise hardware that prevented high intensity training. PURPOSE: This study sought to determine if a countermeasure program that included intense lower-body resistive and rowing exercises designed to prevent cardiovascular and musculoskeletal deconditioning during 70 days of 6 deg head-down tilt bed rest (BR), a spaceflight analog, also would protect against post- BR orthostatic intolerance. METHODS: Sixteen males participated in this study and performed no exercise (Control, n=10) or performed an intense supine exercise protocol with resistive and aerobic components (Exercise, n=6). On 3 days/week, exercise subjects performed lower body resistive exercise and a 30-min continuous bout of rowing (greater than or equal to 75% max heart rate). On 3 other days/week, subjects performed only high-intensity, interval-style rowing. Orthostatic intolerance was assessed using a 15-min 80 deg head-up tilt test performed 2 days (BR-2) before and on the last day of BR (BR70). Plasma volume was measured using a carbon monoxide rebreathing technique on BR-3 and before rising on the first recovery day (BR+0). RESULTS: Following 70 days of BR, tilt tolerance time decreased significantly in both the Control (BR-2: 15.0 +/- 0.0, BR70: 9.9 +/- 4.6 min, mean +/- SD) and Exercise (BR-2: 12.2 +/- 4.7, BR70: 4.9 +/- 1.9 min) subjects, but the decreased tilt tolerance time was not different between groups (Control: -34 +/- 31, Exercise: -56 +/- 16%). Plasma volume also decreased (Control: -0.56 +/- 0.40, Exercise: -0.48 +/- 0.33 L) from pre to post-BR, with no differences between groups (Control: -18 +/- 11%, Exerciser: -15 +/-1 0%). CONCLUSIONS: These findings confirm previous reports in shorter BR studies that the performance of an exercise countermeasure protocol by itself during BR does not prevent orthostatic intolerance or plasma volume loss. This suggests that protection against orthostatic intolerance in astronauts following long-duration spaceflight will require an additional intervention, such as periodic orthostatic stress, fluid repletion, and/or lower-body compression garments.
Lee, M K; Park, S Y; Choi, G-S
2018-05-01
The purpose of this study was to examine the association of support from family and friends for adoption of healthy eating habits and performing exercise with improvements of self-leadership in patients with colorectal cancer (CRC). This cross-sectional study examined 251 patients with CRC who received primary curative surgery in South Korea. Demographic and clinical information, receipt of social support for adoption of healthy eating habits and performing exercise and self-leadership were collected. Greater participation by family and the use of rewards for performance of exercise were associated with greater behavioural awareness and volition, greater task motivation and constructive cognition of self-leadership in patients. Patients exercising with friends had greater task motivation in self-leadership. The use of rewards by family was associated with performing and maintaining exercise programme for more than 6 months, and family encouragement to adopt healthy eating habits was associated with excellent quality of diet. Family support for exercising and adopting healthy eating habits had more wide-ranging benefits in self-leadership than support from friends; however, support from each group improved self-leadership. Support from family was valuable for increasing the actual performance of exercise and for helping patients with cancer to adopt healthy diets. © 2018 John Wiley & Sons Ltd.
Effects of an acute bout of exercise on memory in 6th grade children.
Etnier, Jennifer; Labban, Jeffrey D; Piepmeier, Aaron; Davis, Matthew E; Henning, David A
2014-08-01
Research supports the positive effects of exercise on cognitive performance by children. However, a limited number of studies have explored the effects specifically on memory. The purpose of this study was to compare the effects of an acute bout of exercise on learning, short-term memory, and long-term memory in a sample of children. Children were randomly assigned to an exercise condition or to a no-treatment control condition and then performed repeated trials on an auditory verbal learning task. In the exercise condition, participants performed the PACER task, an aerobic fitness assessment, in their physical education class before performing the memory task. In the control condition, participants performed the memory task at the beginning of their physical education class. Results showed that participants in the exercise condition demonstrated significantly better learning of the word lists and significantly better recall of the words after a brief delay. There were not significant differences in recognition of the words after an approximately 24-hr delay. These results provide evidence in a school setting that an acute bout of exercise provides benefits for verbal learning and long-term memory. Future research should be designed to identify the extent to which these findings translate to academic measures.
Wang, Ching-Yi; Yeh, Chih-Jung; Wang, Chia-Wei; Wang, Chun-Feng; Lin, Yen-Ling
2011-03-01
To examine the effect of regular ongoing exercise lifestyle on mental and physical health in a group of independent community-dwelling Taiwanese older adults over a 2-year period. 197 older adults (mean age 72.5 years; 106 men and 91 women) who were independent in walking, instrumental and basic activities of daily living completed the baseline and a 2-year follow-up assessment. Older adults regularly performing exercises during the 2-year study period were grouped into regular exercise group; otherwise in the irregular exercise group. Baseline and follow-up assessments included a face-to-face interview and a battery of performance tests. The regular exercise group showed significantly less depression (P = 0.03) and tended to regress less on the performance tests (P = 0.025-0.410) across 2 years compared to the irregular exercise group. Regular exercise is important for maintaining or even improving mental and functional health, even for independent community-dwelling older adults. © 2010 The Authors. Australasian Journal on Ageing © 2010 ACOTA.
Optimal technique for deep breathing exercises after cardiac surgery.
Westerdahl, E
2015-06-01
Cardiac surgery patients often develop a restrictive pulmonary impairment and gas exchange abnormalities in the early postoperative period. Chest physiotherapy is routinely prescribed in order to reduce or prevent these complications. Besides early mobilization, positioning and shoulder girdle exercises, various breathing exercises have been implemented as a major component of postoperative care. A variety of deep breathing maneuvres are recommended to the spontaneously breathing patient to reduce atelectasis and to improve lung function in the early postoperative period. Different breathing exercises are recommended in different parts of the world, and there is no consensus about the most effective breathing technique after cardiac surgery. Arbitrary instructions are given, and recommendations on performance and duration vary between hospitals. Deep breathing exercises are a major part of this therapy, but scientific evidence for the efficacy has been lacking until recently, and there is a lack of trials describing how postoperative breathing exercises actually should be performed. The purpose of this review is to provide a brief overview of postoperative breathing exercises for patients undergoing cardiac surgery via sternotomy, and to discuss and suggest an optimal technique for the performance of deep breathing exercises.
Exercising attention within the classroom.
Hill, Liam; Williams, Justin H G; Aucott, Lorna; Milne, June; Thomson, Jenny; Greig, Jessie; Munro, Val; Mon-Williams, Mark
2010-10-01
to investigate whether increased physical exercise during the school day influenced subsequent cognitive performance in the classroom. a randomized, crossover-design trial (two weeks in duration) was conducted in six mainstream primary schools (1224 children aged 8-11y). No data on sex was available. Children received a teacher-directed, classroom-based programme of physical exercise, delivered approximately 30 minutes after lunch for 15 minutes during one week and no exercise programme during the other (order counterbalanced across participants). At the end of each school day, they completed one of five psychometric tests (paced serial addition, size ordering, listening span, digit-span backwards, and digit-symbol encoding), so that each test was delivered once after exercise and once after no exercise. general linear modelling analysis demonstrated a significant interaction between intervention and counterbalance group (p<0.001), showing that exercise benefitted cognitive performance. Post-hoc analysis revealed that benefits occurred in participants who received the exercise intervention in the second but not the first week of the experiment and were also moderated by type of test and age group. physical exercise benefits cognitive performance within the classroom. The degree of benefit depends on the context of testing and participants' characteristics. This has implications for the role that is attributed to physical exercise within the school curriculum.
Experimental Effects of Acute Exercise on Prospective Memory and False Memory.
Green, David; Loprinzi, Paul D
2018-01-01
Research demonstrates that acute exercise can enhance retrospective episodic memory performance. However, limited research has examined the effects of acute exercise on prospective memory, and no studies have examined the effects of exercise on false memory performance. This study examined the potential effects of acute exercise on prospective memory and false memory performance. A between-group randomized controlled trial was employed, with participants (college students; M age = 20 years) randomized into an exercise group (15-minute acute bout of treadmill walking; N = 25) or a control group (15 minutes of sitting; N = 26). Prospective memory was assessed from two laboratory and two naturalistic assessments outside the lab. False memory was assessed using a word-list trial. There were no statistically significant differences in prospective memory based on group allocation (F Group×Time = 1.17; P = 0.32; η 2 = 0.06). However, the control group recalled more false words and had a higher rate of false memory recognition (F Group×Time = 3.15; P = 0.01; η 2 = 0.26). These findings indicate that acute moderate-intensity aerobic exercise is not associated with prospective memory performance but provides some suggestive evidence that acute exercise may reduce the rate of false memories.
Calé-Benzoor, Maya; Maenhout, Annelies; Arnon, Michal; Tenenbaum, Gershon; Werrin, Mia; Cools, Ann
2017-07-01
The purpose of the study was to evaluate performance quality of shoulder plyometric exercises, and examine the relationship to scapular muscle activation during an intense exercise bout. Observational study. University laboratory. 32 healthy university students (male/female: 14/18) volunteers. Subjects performed 10 plyometric exercises. Surface EMG of upper (UT), middle (MT) and lower (LT) trapezius and serratus anterior (SA) was registered. A quality assessment questionnaire was administered at the beginning and end of the exercise bout. Muscle activation at the beginning and end was evaluated by t-test. Mixed repeated measures ANOVA was conducted to test the effects of criterion-quality, time, muscles, exercises, and their interactions. Increased EMG activation was noted in 34/40 cases, (21/40 significant (p < 0.05) changes). Quality assessment revealed a decline in the ability to maintain initial position (43% of subjects), failure to keep a consistent and symmetrical arc of motion (62% of subjects), and performance with trick movements (48% of subjects). Inability to keep a consistent arc of motion was significant in 4 exercises. The novel questionnaire may aid quality assessment during plyometric exercises. Ability to keep a consistent arc of motion was the most sensitive marker of decline of performance quality. Copyright © 2017 Elsevier Ltd. All rights reserved.
Arkkukangas, Marina; Söderlund, Anne; Eriksson, Staffan; Johansson, Ann-Christin
2017-02-27
In Western countries, falls and fall-related injuries are a well-known threat to health in the aging population. Studies indicate that regular exercise improves strength and balance and can therefore decrease the incidence of falls and fall-related injuries. The challenge, however, is to provide exercise programs that are safe, effective, and attractive to the older population. The aim of this study was to investigate the short-term effect of a home-based exercise program with or without motivational interviewing (MI) compared with standard care on physical performance, fall self-efficacy, balance, activity level, handgrip strength, adherence to the exercise, and fall frequency. A total of 175 older adults participated in this randomized controlled study. They were randomly allocated for the Otago Exercise Program (OEP) (n = 61), OEP combined with MI (n = 58), or a control group (n = 56). The participants' mean age was 83 years. The recruitment period was from October 2012 to May 2015. Measurements of physical performance, fall self-efficacy, balance, activity level, handgrip strength, adherence to the exercise, and fall frequency were done before and 12 weeks after randomization. A total of 161 participants were followed up, and there were no significant differences between groups after a period of 12 weeks of regular exercise. Within the OEP + MI group, physical performance, fall self-efficacy, physical activity level, and handgrip strength improved significantly; likewise, improved physical performance and fall self-efficacy were found in the control group. A corresponding difference did not occur in the OEP group. Adherence to the exercise was generally high in both exercise groups. In the short-term perspective, there were no benefits of an exercise program with or without MI regarding physical performance, fall self-efficacy, activity level, handgrip strength, adherence to the exercise, and fall frequency in comparison to a control group. However, some small effects occurred within the OEP + MI group, indicating that there may be some possible value in behavioral change support combined with exercise in older adults that requires further evaluation in both short- and long-term studies.
De Marchi, Thiago; Leal Junior, Ernesto Cesar Pinto; Bortoli, Celiana; Tomazoni, Shaiane Silva; Lopes-Martins, Rodrigo Alvaro Brandão; Salvador, Mirian
2012-01-01
The aim of this work was to evaluate the effects of low-level laser therapy (LLLT) on exercise performance, oxidative stress, and muscle status in humans. A randomized double-blind placebo-controlled crossover trial was performed with 22 untrained male volunteers. LLLT (810 nm, 200 mW, 30 J in each site, 30 s of irradiation in each site) using a multi-diode cluster (with five spots - 6 J from each spot) at 12 sites of each lower limb (six in quadriceps, four in hamstrings, and two in gastrocnemius) was performed 5 min before a standardized progressive-intensity running protocol on a motor-drive treadmill until exhaustion. We analyzed exercise performance (VO(2 max), time to exhaustion, aerobic threshold and anaerobic threshold), levels of oxidative damage to lipids and proteins, the activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), and the markers of muscle damage creatine kinase (CK) and lactate dehydrogenase (LDH). Compared to placebo, active LLLT significantly increased exercise performance (VO(2 max) p = 0.01; time to exhaustion, p = 0.04) without changing the aerobic and anaerobic thresholds. LLLT also decreased post-exercise lipid (p = 0.0001) and protein (p = 0.0230) damages, as well as the activities of SOD (p = 0.0034), CK (p = 0.0001) and LDH (p = 0.0001) enzymes. LLLT application was not able to modulate CAT activity. The use of LLLT before progressive-intensity running exercise increases exercise performance, decreases exercise-induced oxidative stress and muscle damage, suggesting that the modulation of the redox system by LLLT could be related to the delay in skeletal muscle fatigue observed after the use of LLLT.
Towards a cognitive resource limitations model of diminished expression in schizotypy.
Cohen, Alex S; Morrison, Sean C; Brown, Laura A; Minor, Kyle S
2012-02-01
Diminished expression of speech is a pernicious feature of both schizophrenia and schizotypy--defined as the personality organization reflecting a putative genetic schizophrenia liability. As yet, the mechanism underlying diminished expression is unclear. We tested the hypothesis that diminished expression reflects a cognitive resource issue--that is, as cognitive resources are depleted, expression becomes diminished in individuals with psychometrically defined schizotypy. Acoustic analysis of natural speech was procured during experimentally manipulated baseline and high cognitive-load dual tasks and examined in 38 individuals with psychometrically defined schizotypy and 34 controls. For both groups, expression significantly decreased as a function of increased task demands, although there were no group differences in expression or magnitude of change across baseline to high cognitive-load conditions. Participants with self-reported constricted affect showed significant reductions in expression under high-load versus baseline speaking conditions relative to other schizotypal and control participants. Moreover, psychometrically defined schizotypal participants with poor cognitive performance on the high-load task, suggestive of depleted cognitive resources, also showed expressivity reductions compared with other participants. These findings suggest that diminished expression occurs as a function of limited cognitive resources in psychometrically defined schizotypy. PsycINFO Database Record (c) 2012 APA, all rights reserved.
Muscle activity in upper and lower rectus abdominus during abdominal exercises.
Sarti, M A; Monfort, M; Fuster, M A; Villaplana, L A
1996-12-01
To compare the intensity of the upper versus lower rectus abdominis (RA) muscle activity provoked by each of two different abdominal exercises and to contrast the intensity of contraction elicited by two different abdominal exercises on each RA muscle portion. Nonrandomized control trial. Kinesiology laboratory in a university medicine faculty. Convenience sample of 33 healthy volunteers. Subjects who had practiced endurance or strength training activities (1.5 hours 3 days a week for 3 years) and those who had not accomplished that criterion comprised a high and a low physical activity group, respectively. Each of these two groups was divided by the ability to perform the exercises into two subgroups: correct and incorrect performers (cp, ic). Average surface iEMG was compared between upper and lower RA and on each muscle portion performing curl-up (CU) and posterior pelvic tilt (PT) exercises. The coefficient of variation, a two-way analysis of variance, and the t test were calculated. The upper RA showed significantly greater activity during performance of CU exercise by the cp subgroups of both high (t = 2.14302, 95%) and low (t = 2.35875, 95%) activity groups. Only the cp subgroup of the high activity group showed that PT was significantly more strenuous than CU exercise on lower RA (t = -2.06467, 95%). Among correct performers, CU produces greater activity on upper RA. For persons who have a high level of activity, PT is more strenuous than CU on lower RA. Among incorrect performers, either exercise indistinctly activates the muscle portions.
Effect of different warm-up procedures on the performance of resistance training exercises.
Ribeiro, Alex S; Romanzini, Marcelo; Schoenfeld, Brad J; Souza, Mariana F; Avelar, Ademar; Cyrino, Edilson S
2014-08-01
Warm-up has been shown to mediate numerous acute physiological alterations that have been purported to confer beneficial effects on performance. This study investigated the acute effects of different warm-up procedures on resistance training performance. Employing a randomized, counterbalanced crossover design, 15 men performed 3 exercises (4 sets of bench press, squat, and arm curl at 80% of 1RM) to failure in 4 conditions (control, specific, aerobic, and combined). Outcome measures included the sum of repetitions and a fatigue index measuring the decline between sets. There was no significant difference for the sum of repetitions or for fatigue index among conditions for the 3 exercises. Performance in the resistance training exercises was not influenced by warm-up.
Bruggers, Carol S; Baranowski, Sabrina; Beseris, Mathew; Leonard, Rachel; Long, Derek; Schulte, Elizabeth; Shorter, Ashton; Stigner, Rowan; Mason, Clinton C; Bedrov, Alisa; Pascual, Ian; Bulaj, Grzegorz
2018-01-01
Medical advances continue to improve morbidity and mortality of serious pediatric diseases, including cancer, driving research addressing diminished physical and psychological quality of life in children with these chronic conditions. Empowerment enhances resilience and positively influences health, disease, and therapy understanding. We describe the development and usability assessment of a prototype Empower Stars! mobile video game grounded in behavioral and exercise theories with the purpose of coupling physical exercise with empowerment over disease in children with cancer. Academic faculty, health-care providers, and community video game developers collaborated in this project. The iPadAir was selected as a delivery platform for its accelerometer and gyroscope features facilitating exercise design. Unity multiplatform technology provided animation and audiovisual features for immediate player feedback. Javascript, C#, Photoshop, Flash, and SketchUp were used for coding, creating graphical assets, Sprite sheets, and printing files, respectively. 3D-printed handles and case backing were used to adapt the iPad for physical exercise. Game usability, engagement, and enjoyment were assessed via a multilevel study of children undergoing cancer chemotherapy, their parents, and pediatric cancer health-care providers. Feedback crucial for ongoing game development was analyzed. A prototype Empower Stars! mobile video game was developed for children 7-14 years old with cancer. Active, sedentary, educational, and empowerment-centered elements intermix for 20 min of exercise within a 30 min "one-day treatment" gameplay session involving superheroes, space exploration, metaphorical cancer challenges, life restoration on a barren planet, and innumerable star rewards. No player "dies." Usability assessment data analyses showed widespread enthusiasm for integrating exercise with empowerment over cancer and the game itself. Favorite elements included collecting star rewards and planet terraforming. Traveling in space and the Healthy Food Choice game were least liked. The need for improved gameplay instructions was expressed by all groups. The usability study provided essential feedback for converting the prototype into alpha version of Empower Stars! Adapting exercise empowerment-promoting video game technology to mobile platforms facilitates usability and widespread dissemination for children with cancer. We discuss broader therapeutic applicability in diverse chronic pediatric diseases, including obesity, asthma, cystic fibrosis, diabetes, and juvenile idiopathic arthritis.
Guevara-Aguirre, Jaime; Procel, Patricio; Guevara, Carolina; Guevara-Aguirre, Marco; Rosado, Verónica; Teran, Enrique
2016-06-01
In the present pandemics of obesity and insulin resistant diabetes mellitus (DM), the specific contribution of etiological factors such as shifts in nutritional and exercise patterns, genetic and hormonal, is subject of ongoing research. Among the hormonal factors implicated, we selected obesity-driven insulin resistance for further evaluation. It is known that growth hormone (GH) has profound effects on carbohydrate metabolism. In consequence, we compared the effects of the lack of the counter-regulatory effects of GH, in a group of subjects with GH receptor deficiency (GHRD) due to a mutated GH receptor vs. that of their normal relatives. It was found that, despite their obesity, subjects with GHRD, have diminished incidence of diabetes, lower glucose and insulin concentrations, and lower values of indexes indicative of insulin resistance such as HOMA-IR. The GHRD subjects were also capable of appropriately handling glucose or mixed meal loads despite diminished insulin secretion. These observations allow us to suggest that the association of obesity with increased risk for diabetes appears to be dependent on intact growth hormone signaling. Copyright © 2015 Elsevier Ltd. All rights reserved.
Pilot Biofeedback Training in the Cognitive Awareness Training Study (CATS)
NASA Technical Reports Server (NTRS)
Uenking, M.
2000-01-01
One of the ongoing problems that pilots face today is a diminished state of awareness such as boredom, sleepiness, or fatigue during cruise conditions that could result in various pilot errors. This study utilized a cognitive training exercise to sharpen the pilot's awareness during simulated flight thereby providing them with a means to overcome these diminished states of awareness. This study utilizes psychophysiological methods in an attempt to assess a pilot's state of awareness more directly. In turn, the pilots will be able to train themselves to recognize these states of awareness and be more mentally sharp during mundane tasks such as those experienced in cruise conditions. The use of these measurement tools may be beneficial for researchers working within the NASA Aviation Safety Program. This paper will provide the reader with some background information concerning the motivation for the study, a brief description of the experimental setup and design matrix, the dependent and independent variables that were employed, and some preliminary findings based on some of the subjective and objective data that was collected. These preliminary findings are of part of an ongoing study being conducted at the NASA Langley Research Center in Hampton, Virginia.
Blondheim, David S; Yosef, Avigail; Marmor, Alon T
2004-12-01
Patients with ischaemic heart disease have to perform exercise tests repeatedly. It is not clear if a small meal eaten before the test might influence it and if the meal's composition is important. We performed a double blind, randomised, crossover study on 20 volunteers with documented ischaemic heart disease known to have positive exercise tests. Each had three symptom limited exercise tests done one hour after a 200 ml meal, rich in either fat, carbohydrate or protein. Each postprandial test was compared to a fasting exercise test performed just before the meal. Postprandial blood pressure, time to angina and to peak exercise and double product at onset of ST-depression were not significantly altered by any of the meals. Heart rate was slightly increased only after the fat meal. The nutritional composition of a small meal eaten an hour before an exercise test has no clinically important impact on the results of the test in patients with stable angina pectoris.
Acute coordinative exercise improves attentional performance in adolescents.
Budde, Henning; Voelcker-Rehage, Claudia; Pietrabyk-Kendziorra, Sascha; Ribeiro, Pedro; Tidow, Günter
2008-08-22
Teachers complain about growing concentration deficits and reduced attention in adolescents. Exercise has been shown to positively affect cognitive performance. Due to the neuronal connection between the cerebellum and the frontal cortex, we hypothesized that cognitive performance might be influenced by bilateral coordinative exercise (CE) and that its effect on cognition might be already visible after short bouts of exercise. One hundred and fifteen healthy adolescents aged 13-16 years of an elite performance school were randomly assigned to an experimental and a control group and tested using the d2-test, a test of attention and concentration. Both groups performed the d2-test after a regular school lesson (pre-test), after 10 min of coordinative exercise and of a normal sport lesson (NSL, control group), respectively (post-test). Exercise was controlled for heart rate (HR). CE and NSL enhanced the d2-test performance from pre- to post-test significantly. ANOVA revealed a significant group (CE, NSL) by performance interaction in the d2-test indicating a higher improvement of CE as compared to NSL. HR was not significantly different between the groups. CE was more effective in completing the concentration and attention task. With the HR being the same in both groups we assume that the coordinative character of the exercise might be responsible for the significant differences. CE might lead to a pre-activation of parts of the brain which are also responsible for mediating functions like attention. Thus, our results support the request for more acute CE in schools, even in elite performance schools.
Candia-Luján, Ramón; De Paz Fernández, José Antonio; Costa Moreira, Osvaldo
2014-10-05
In recent years, antioxidant supplements have become popular to counter the effects of free radicals and muscle damage symptoms, including delayed onset muscle soreness (DOMS). To conduct a systematic review in different databases to determine the effects of antioxidant supplements on DOMS. We conducted a search in databases; Cochrane, Pubmed, Scopus and SportDiscus and Web of Science (WOS). The words and acronyms used were; Delayed onset muscle soreness, exercise induced muscle damage, DOMS, EIMD, antioxidant and oxidative stress. 54 articles were identified of which 48 were retreived, all in English, 17 related to vitamin C and E, supplements polyphenolic correspond to fourteen, eleven other antioxidant supplements and six to commercial supplements, all of them used to diminish the DOMS and other variables. Both vitamins and commercial supplements have low effectiveness in reducing DOMS, while polyphenols and other antioxidant supplements show moderate to good effectiveness in combating DOMS. However, most of the studies have effectiveness in reducing other symptoms of muscle damage besides helping in the post-exercise recovery. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
Alterations in protein metabolism during space flight and inactivity
NASA Technical Reports Server (NTRS)
Ferrando, Arny A.; Paddon-Jones, Doug; Wolfe, Robert R.
2002-01-01
Space flight and the accompanying diminished muscular activity lead to a loss of body nitrogen and muscle function. These losses may affect crew capabilities and health in long-duration missions. Space flight alters protein metabolism such that the body is unable to maintain protein synthetic rates. A concomitant hypocaloric intake and altered anabolic/catabolic hormonal profiles may contribute to or exacerbate this problem. The inactivity associated with bedrest also reduces muscle and whole-body protein synthesis. For this reason, bedrest provides a good model for the investigation of potential exercise and nutritional countermeasures to restore muscle protein synthesis. We have demonstrated that minimal resistance exercise preserves muscle protein synthesis throughout bedrest. In addition, ongoing work indicates that an essential amino acid and carbohydrate supplement may ameliorate the loss of lean body mass and muscle strength associated with 28 d of bedrest. The investigation of inactivity-induced alterations in protein metabolism, during space flight or prolonged bedrest, is applicable to clinical populations and, in a more general sense, to the problems associated with the decreased activity that occur with aging.
Effects of intervals between jumps or bouts on osteogenic response to loading.
Umemura, Yoshihisa; Sogo, Naota; Honda, Akiko
2002-10-01
Prolonged loading repetitions can diminish the mechanosensitivity of bones, and increased intervals between loading might restore sensitivity. This study was designed to investigate the effects of intervals between loadings or bouts on osteogenic response. Forty female Fisher 344 rats aged 5 wk were divided into a control group and three exercise groups: 20 jumps in a single bout with a 3-s (S3) or 30-s (S30) jump interval, or 20 jumps in 2 bouts (10 x 2) separated by a 6-h interval with a 3-s jump interval (D3). After 8 wk of training, the bone masses per body weight of the femur and tibia were significantly greater in the three exercise groups than in the control group, and these values were also greater in S30 than in S3, although they were at the same level in D3 and S3. These data suggest that a longer interval (30 s) between individual loading had more effective anabolic effects on bone than a shorter interval (3 s).
Biomarkers in Sports and Exercise: Tracking Health, Performance, and Recovery in Athletes.
Lee, Elaine C; Fragala, Maren S; Kavouras, Stavros A; Queen, Robin M; Pryor, John Luke; Casa, Douglas J
2017-10-01
Biomarker discovery and validation is a critical aim of the medical and scientific community. Research into exercise and diet-related biomarkers aims to improve health, performance, and recovery in military personnel, athletes, and lay persons. Exercise physiology research has identified individual biomarkers for assessing health, performance, and recovery during exercise training. However, there are few recommendations for biomarker panels for tracking changes in individuals participating in physical activity and exercise training programs. Our approach was to review the current literature and recommend a collection of validated biomarkers in key categories of health, performance, and recovery that could be used for this purpose. We determined that a comprehensive performance set of biomarkers should include key markers of (a) nutrition and metabolic health, (b) hydration status, (c) muscle status, (d) endurance performance, (e) injury status and risk, and (f) inflammation. Our review will help coaches, clinical sport professionals, researchers, and athletes better understand how to comprehensively monitor physiologic changes, as they design training cycles that elicit maximal improvements in performance while minimizing overtraining and injury risk.
Dutke, Stephan; Jaitner, Thomas; Berse, Timo; Barenberg, Jonathan
2014-02-01
Research on effects of acute physical exercise on performance in a concurrent cognitive task has generated equivocal evidence. Processing efficiency theory predicts that concurrent physical exercise can increase resource requirements for sustaining cognitive performance even when the level of performance is unaffected. This hypothesis was tested in a dual-task experiment. Sixty young adults worked on a primary auditory attention task and a secondary interval production task while cycling on a bicycle ergometer. Physical load (cycling) and cognitive load of the primary task were manipulated. Neither physical nor cognitive load affected primary task performance, but both factors interacted on secondary task performance. Sustaining primary task performance under increased physical and/or cognitive load increased resource consumption as indicated by decreased secondary task performance. Results demonstrated that physical exercise effects on cognition might be underestimated when only single task performance is the focus.
Transient myocardial tissue and function changes during a marathon in less fit marathon runners.
Gaudreault, Valerie; Tizon-Marcos, Helena; Poirier, Paul; Pibarot, Philippe; Gilbert, Philippe; Amyot, Marc; Rodés-Cabau, Josep; Després, Jean-Pierre; Bertrand, Olivier; Larose, Eric
2013-10-01
Although regular physical activity improves health, strenuous exercise might transiently increase cardiac risk. Training and fitness might provide protection. We prospectively studied 20 recreational marathon runners without known cardiovascular disease or symptoms: at peak training before, immediately after, and 3 months after a 42.2-km marathon. Changes in global/segmental myocardial function, edema, resting perfusion, and fibrosis were measured. At peak training, runners exercised 8.1 ± 2.3 hours and 62 ± 18 km per week with mean maximal oxygen consumption (VO2max) of 53.2 ± 8.3 mL/kg/min. In response to the marathon, global left ventricular and right ventricular ejection fraction decreased in half of the runners; these runners had poorer peak training distance, training time, and fitness level. Change in global left ventricular ejection fraction was associated with VO2max. Overall, 36% of segments developed edema, 53% decreased function, and 59% decreased perfusion. Significant agreement was observed between segment decreasing function, decreasing perfusion, and developing edema. Myocardial changes were reversible at 3 months. Completing a marathon leads to localized myocardial edema, diminished perfusion, and decreased function occurring more extensively in less trained and fit runners. Although reversible, these changes might contribute to the transient increase in cardiac risk reported during sustained vigorous exercise. Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
Human cloning and embryo research: the 2003 John J. Conley Lecture on medical ethics.
George, Robert P
2004-01-01
The author, a member of the U.S. President's Council on Bioethics, discusses ethical issues raised by human cloning, whether for purposes of bringing babies to birth or for research purposes. He first argues that every cloned human embryo is a new, distinct, and enduring organism, belonging to the species Homo sapiens, and directing its own development toward maturity. He then distinguishes between two types of capacities belonging to individual organisms belonging to this species, an immediately exerciseable capacity and a basic natural capacity that develops over time. He argues that it is the second type of capacity that is the ground for full moral respect, and that this capacity (and its concomitant degree of respect) belongs to cloned human embryos no less than to adult human beings. He then considers and rejects counter-arguments to his position, including the suggestion that the capacity of embryos is equivalent to the capacity of somatic cells, that full human rights are afforded only to human organisms with functioning brains, that the possibility of twinning diminishes the moral status of embryos, that the fact that people do not typically mourn the loss of early embryos implies that they have a diminished moral status, that the fact that early spontaneous abortions occur frequently diminishes the moral status of embryos, and that his arguments depend upon a concept of ensoulment. He concludes that if the moral status of cloned human embryos is equivalent to that of adults, then public policy should be based upon this assumption.
Castro-Sepulveda, Mauricio; Johannsen, Neil; Astudillo, Sebastián; Jorquera, Carlos; Álvarez, Cristian; Zbinden-Foncea, Hermann; Ramírez-Campillo, Rodrigo
2016-06-07
Fluid and electrolyte status have a significant impact on physical performance and health. Pre-exercise recommendations cite the possibility of consuming beverages with high amounts of sodium. In this sense, non-alcoholic beer can be considered an effective pre-exercise hydration beverage. This double-blind, randomized study aimed to compare the effect of beer, non-alcoholic beer and water consumption before exercise on fluid and electrolyte homeostasis. Seven male soccer players performed 45 min of treadmill running at 65% of the maximal heart rate, 45 min after ingesting 0.7 L of water (W), beer (AB) or non-alcoholic beer (NAB). Body mass, plasma Na⁺ and K⁺ concentrations and urine specific gravity (USG) were assessed before fluid consumption and after exercise. After exercise, body mass decreased (p < 0.05) in W (-1.1%), AB (-1.0%) and NAB (-1.0%). In the last minutes of exercise, plasma Na⁺ was reduced (p < 0.05) in W (-3.9%) and AB (-3.7%), plasma K⁺ was increased (p < 0.05) in AB (8.5%), and USG was reduced in W (-0.9%) and NAB (-1.0%). Collectively, these results suggest that non-alcoholic beer before exercise could help maintain electrolyte homeostasis during exercise. Alcoholic beer intake reduced plasma Na⁺ and increased plasma K⁺ during exercise, which may negatively affect health and physical performance, and finally, the consumption of water before exercise could induce decreases of Na⁺ in plasma during exercise.
Kane, Irene; Robertson, Robert J; Fertman, Carl I; Nagle, Elizabeth F; McConnaha, Wendell R; Rabin, Bruce S
2013-10-01
Self-efficacy and enjoyment were examined among 34 middle school children (M age = 12.5 yr.) performing the Progressive Aerobic Cardiovascular Endurance Run (PACER). Exercise self-efficacy (running) and physical activity enjoyment were measured after viewing a video illustrating the PACER, and subsequently following a PACER test. Significantly greater pre- than post-exercise self-efficacy was reported; enjoyment scores did not differ. Ratings of self-efficacy were higher before exercise than after, but enjoyment scores were not significantly different. A significant correlation was found between post-exercise self-efficacy and enjoyment, but not between pre-exercise self-efficacy and enjoyment. Although positive correlations were found between PACER laps and pre-/post-exercise self-efficacy, correlations with ratings of enjoyment were not significant. Exercise self-efficacy was associated with children's beliefs about the task-specific PACER aerobic exercise; however, exercise enjoyment was stable. Children's self-efficacy and enjoyment beliefs should be considered when developing interventional strategies to promote aerobic exercise participation.
IMMEDIATE EFFECTS OF DEEP TRUNK MUSCLE TRAINING ON SWIMMING START PERFORMANCE.
Iizuka, Satoshi; Imai, Atsushi; Koizumi, Keisuke; Okuno, Keisuke; Kaneoka, Koji
2016-12-01
In recent years, deep trunk muscle training has been adopted in various sports, including swimming. This is performed both in everyday training and as part of the warm-up routine before competitive races. It is suggested that trunk stabilization exercises are effective in preventing injury, and aid in improving performance. However, conclusive evidence of the same is yet to be obtained. The time of start phase of swimming is a factor that can significantly influence competition performance in a swimming race. If trunk stabilization exercises can provide instantaneous trunk stability, it is expected that they will lead to performance improvements in the start phase of swimming. The purpose of this study was to investigate the immediate effect of trunk stabilization exercises on the start phase in swimming. Intervention study. Nine elite male swimmers (mean age 20.2 ± 1.0 years; height 174.4 ± 3.5 cm; weight 68.9 ± 4.1 kg) performed the swimming start movement. The measurement variables studied included flying distance, and the time and velocity of subjects at hands' entry and on reaching five meters. Measurements were taken in trials immediately before and after the trunk stabilization exercises. A comparison between pre- and post-exercise measurements was assessed. The time to reach five meters (T 5m ) decreased significantly after trunk stabilization exercises, by 0.019 s (p = 0.02). Velocity at entry (V entry ) did not demonstrate significant change, while velocity at five meters (V 5m ) increased significantly after the exercises (p = 0.023). In addition, the speed reduction rate calculated from V entry and V 5m significantly decreased by 5.17% after the intervention (p = 0.036). Trunk stabilization exercises may help reduce the time from start to five meters in the start phase in swimming. The results support the hypothesis that these exercises may improve swimming performance. Level 3b.
Palazzo, Clémence; Klinger, Evelyne; Dorner, Véronique; Kadri, Abdelmajid; Thierry, Olivier; Boumenir, Yasmine; Martin, William; Poiraudeau, Serge; Ville, Isabelle
2016-04-01
To assess views of patients with chronic low back pain (cLBP) concerning barriers to home-based exercise program adherence and to record expectations regarding new technologies. Qualitative study based on semi-structured interviews. A heterogeneous sample of 29 patients who performed a home-based exercise program for cLBP learned during supervised physiotherapy sessions in a tertiary care hospital. Patients were interviewed at home by the same trained interviewer. Interviews combined a funnel-shaped structure and an itinerary method. Barriers to adherence related to the exercise program (number, effectiveness, complexity and burden of exercises), the healthcare journey (breakdown between supervised sessions and home exercise, lack of follow-up and difficulties in contacting care providers), patient representations (illness and exercise perception, despondency, depression and lack of motivation), and the environment (attitudes of others, difficulties in planning exercise practice). Adherence could be enhanced by increasing the attractiveness of exercise programs, improving patient performance (following a model or providing feedback), and the feeling of being supported by care providers and other patients. Regarding new technologies, relatively younger patients favored visual and dynamic support that provided an enjoyable and challenging environment and feedback on their performance. Relatively older patients favored the possibility of being guided when doing exercises. Whatever the tool proposed, patients expected its use to be learned during a supervised session and performance regularly checked by care providers; they expected adherence to be discussed with care providers. For patients with cLBP, adherence to home-based exercise programs could be facilitated by increasing the attractiveness of the programs, improving patient performance and favoring a feeling of being supported. New technologies meet these challenges and seem attractive to patients but are not a substitute for the human relationship between patients and care providers. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Thomson, Rebecca L; Bellenger, Clint R; Howe, Peter R C; Karavirta, Laura; Buckley, Jonathan D
2016-03-01
The recovery of heart rate (HRR) after exercise is a potential indicator of fitness which has been shown to respond to changes in training. This study investigated the within-individual association between HRR and exercise performance following three different training loads. 11 male cyclists/triathletes were tested after two weeks of light training, two weeks of heavy training and two days of rest. Exercise performance was measured using a 5-min maximal cycling time-trial. HRR was measured over 60s during supine recovery. Exercise performance decreased 2.2±2.5% following heavy training compared with post-light training (p=0.01), and then increased 4.0±4.2% following rest (p=0.004). Most HRR indices indicated a more rapid recovery of heart rate (HR) following heavy training, and reverted to post light training levels following two days of rest. HRR indices did not differ between post-light training and after the rest period (p>0.6). There were inverse within-subject relationships between indices of HRR and performance (r=-0.6, p≤0.004). Peak HR decreased 3.2±5.1bpm following heavy training (p=0.06) and significantly increased 4.9±4.3bpm following recovery (p=0.004). There was a moderate within-subject relationship between peak HR and exercise performance (r=0.7, p≤0.001). Controlling for peak HR reduced the relationships between HRR and performance (r=-0.4-0.5, p<0.05). This study demonstrated that HRR tracks short-term changes in exercise performance within-individuals, such that increases in HRR are associated with poorer exercise performance following heavy training. Peak HR can be compromised under conditions of fatigue, and needs to be taken into account in HRR analyses. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Chaouachi, Mehdi; Granacher, Urs; Makhlouf, Issam; Hammami, Raouf; Behm, David G; Chaouachi, Anis
2017-01-01
The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players (13.9 ± 0.3 years) participated in an 8-week training program that either alternated individual balance (e.g., exercises on unstable surfaces) and plyometric (e.g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately >30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence. Key points The combination of balance and plyometric exercises can induce significant and substantial training improvements in muscle strength, power, speed, agility, and balance with adolescent youth athletes The within training session sequence of balance and plyometric exercises does not substantially affect these training improvements. PMID:28344461
Contribution of hamstring fatigue to quadriceps inhibition following lumbar extension exercise.
Hart, Joseph M; Kerrigan, D Casey; Fritz, Julie M; Saliba, Ethan N; Gansneder, Bruce; Ingersoll, Christopher D
2006-01-01
The purpose of this study was to determine the contribution of hamstrings and quadriceps fatigue to quadriceps inhibition following lumbar extension exercise. Regression models were calculated consisting of the outcome variable: quadriceps inhibition and predictor variables: change in EMG median frequency in the quadriceps and hamstrings during lumbar fatiguing exercise. Twenty-five subjects with a history of low back pain were matched by gender, height and mass to 25 healthy controls. Subjects performed two sets of fatiguing isometric lumbar extension exercise until mild (set 1) and moderate (set 2) fatigue of the lumbar paraspinals. Quadriceps and hamstring EMG median frequency were measured while subjects performed fatiguing exercise. A burst of electrical stimuli was superimposed while subjects performed an isometric maximal quadriceps contraction to estimate quadriceps inhibition after each exercise set. Results indicate the change in hamstring median frequency explained variance in quadriceps inhibition following the exercise sets in the history of low back pain group only. Change in quadriceps median frequency explained variance in quadriceps inhibition following the first exercise set in the control group only. In conclusion, persons with a history of low back pain whose quadriceps become inhibited following lumbar paraspinal exercise may be adapting to the fatigue by using their hamstring muscles more than controls. Key PointsA neuromuscular relationship between the lumbar paraspinals and quadriceps while performing lumbar extension exercise may be influenced by hamstring muscle fatigue.QI following lumbar extension exercise in persons with a history of LBP group may involve significant contribution from the hamstring muscle group.More hamstring muscle contribution may be a necessary adaptation in the history of LBP group due to weaker and more fatigable lumbar extensors.
Baeßler, Kaven; Junginger, Bärbel
2017-07-01
The aims of physiotherapy in stress incontinent women are to improve pelvic floor function and the continence mechanism including bladder neck support and urethral closure pressure. In Germany, traditional conservative treatment often includes gymnastic exercises with unclear effects on the bladder neck. The aim of this study was to sonographically assess bladder neck movements during selected exercises. Fifteen healthy, continent women without previous vaginal births, who were able to voluntarily contract their pelvic floor muscels performed the shoulder bridge, the abdominal press, tiptoe and the Pilates clam exercises. The first set was performed without any additional instructions. During the second set directions were given to activate the pelvic floor before beginning each exercise and to maintain the contraction throughout the exercise. Bladder neck movement was measured on perineal ultrasound using a validated method with the pubic symphysis as a reference point. The median age of participants was 32 years, median BMI was 23. Eight women were nulliparous and seven had given birth to 1 - 2 children via caesarean section. When exercises were performed without voluntary pelvic floor contraction the bladder neck descended on average between 2.3 and 4.4 mm, and with pelvic floor contraction prior to the exercise only between 0.5 and 2.1 mm (p > 0.05 except for abdominal press p = 0.007). The Pilates clam exercise and toe stand stabilised the bladder neck most effectively. Bladder neck descent often occurs during pelvic floor gymnastic exercises as traditionally performed in Germany, and a voluntary pelvic floor contraction during the exercises does not necessarily prevent this.
Park, Hun-Young; Kim, Jisu; Park, Miyoung; Chung, Nana; Lim, Kiwon
2018-03-30
The purpose of our study was to determine the effectiveness of carbohydrate loading by additional carbohydrate supplements for 7 days after prolonged interval exercise on exercise performance and energy metabolism during submaximal exercise in team-sports athletes. Twenty male team-sports athletes (14 soccer and 6 rugby players) volunteered to participate in the study and were equally divided into the experimental group (EXP, n=10) performing additional carbohydrate supplementation for 7 days after prolonged interval exercise until blood glucose level reaches 50 mg/dL or less and the control group (CON, n=10). Then, maximal oxygen consumption (VO2max) and minute ventilation (VE), oxygen consumption (VO2), carbon dioxide excretion (VCO2), respiratory exchange ratio (RER), blood glucose level, and blood lactate level were measured in all team-sports players during submaximal exercise corresponding to 70% VO2max before and after intervention. There was no significant interaction in all parameters, but team-sports players in the EXP presented more improved VO2max (CON vs EXP = vs 5.3% vs 6.3%), VE (CON vs EXP = vs 3.8% vs 6.6%), VO2 (CON vs EXP = vs 8.5% vs 9.9%), VCO2 (CON vs EXP = vs 2.8% vs 4.0%), blood glucose level (CON vs EXP = vs -12.9% vs -7.6%), and blood lactate level (CON vs EXP = -18.2% vs -25%) compared to those in the CON. These findings showed that additional carbohydrate supplementation conducted in our study is not effective in exercise performance and energy metabolism during submaximal exercise. ©2018 The Korean Society for Exercise Nutrition.
Passion and Pacing in Endurance Performance
Schiphof-Godart, Lieke; Hettinga, Florentina J.
2017-01-01
Endurance sports are booming, with sports passionates of varying skills and expertise battering city streets and back roads on their weekly or daily exercise rounds. The investments required for performing in endurance exercise are nevertheless considerable, and passion for their sport might explain the efforts endurance athletes are willing to make. Passion may be defined as a strong motivational force and as such might be related to the neurophysiological basis underlying the drive to exercise. A complex relationship between the brain and other systems is responsible for athletes' exercise behavior and thus performance in sports. We anticipate important consequences of athletes' short term choices, for example concerning risk taking actions, on long term outcomes, such as injuries, overtraining and burnout. We propose to consider athletes' type of passion, in combination with neurophysiological parameters, as an explanatory factor inunderstanding the apparent disparity in the regulation of exercise intensity during endurance sports. Previous research has demonstrated that athletes can be passionate toward their sport in either a harmonious or an obsessive way. Although both lead to considerable investments and therefore often to successful performances, obsessive passion may affect athlete well-being and performance on the long run, due to the corresponding inflexible exercise behavior. In this perspective we will thus examine the influence of passion in sport on athletes' short term and long term decision-making and exercise behavior, in particular related to the regulation of exercise intensity, and discuss the expected long term effects of both types of passion for sport. PMID:28265245
Passion and Pacing in Endurance Performance.
Schiphof-Godart, Lieke; Hettinga, Florentina J
2017-01-01
Endurance sports are booming, with sports passionates of varying skills and expertise battering city streets and back roads on their weekly or daily exercise rounds. The investments required for performing in endurance exercise are nevertheless considerable, and passion for their sport might explain the efforts endurance athletes are willing to make. Passion may be defined as a strong motivational force and as such might be related to the neurophysiological basis underlying the drive to exercise. A complex relationship between the brain and other systems is responsible for athletes' exercise behavior and thus performance in sports. We anticipate important consequences of athletes' short term choices, for example concerning risk taking actions, on long term outcomes, such as injuries, overtraining and burnout. We propose to consider athletes' type of passion, in combination with neurophysiological parameters, as an explanatory factor inunderstanding the apparent disparity in the regulation of exercise intensity during endurance sports. Previous research has demonstrated that athletes can be passionate toward their sport in either a harmonious or an obsessive way. Although both lead to considerable investments and therefore often to successful performances, obsessive passion may affect athlete well-being and performance on the long run, due to the corresponding inflexible exercise behavior. In this perspective we will thus examine the influence of passion in sport on athletes' short term and long term decision-making and exercise behavior, in particular related to the regulation of exercise intensity, and discuss the expected long term effects of both types of passion for sport.
Mental Fatigue and Physical and Cognitive Performance During a 2-Bout Exercise Test.
Vrijkotte, Susan; Meeusen, Romain; Vandervaeren, Cloe; Buyse, Luk; Cutsem, Jeroen van; Pattyn, Nathalie; Roelands, Bart
2018-04-01
The 2-bout exercise protocol has been developed to diagnose nonfunctional overreaching and the "overtraining syndrome." It consists of 2 maximal exercise bouts separated by 4 hours. Mental fatigue negatively influences performance, but the effects of its occurrence during the 2-bout exercise protocol have never been investigated. The aim of this study was to examine whether mental fatigue (induced during the rest period) influences physical and cognitive performance during/after the second exercise bout of the 2-bout exercise protocol. Nine healthy, well-trained male cyclists participated in a single-blind, randomized, placebo-controlled crossover study. The intervention consisted of either 1.5-hour rest (control) or performing a computer-based Stroop task to induce mental fatigue. Cognitive (Eriksen Flanker task), physiological (lactate, maximum heart rate, and maximum wattage), and subjective data (mental fatigue-visual analog scale, Profile of Mood States, and rating of perceived exertion) were gathered. Ratings of fatigue, tension, and mental fatigue were affected in the mental fatigue condition (P < .05). Neither physiological nor cognitive differences were found between conditions. Ratings of mental fatigue were already affected after the first maximum exercise test (P < .05). Neither physical nor cognitive performance was affected by mental fatigue, but subjective ratings did reveal significant differences. It is recommended to exclude mentally challenging tasks during the 2-bout exercise protocol rest period to ascertain unaffected subjective test results. This study should be repeated in athletes diagnosed with nonfunctional overreaching/overtraining syndrome.
Brophy-Williams, Ned; Landers, Grant; Wallman, Karen
2011-01-01
The purpose of the study was to determine the effects of cold water immersion (CWI) performed immediately or 3 h after a high intensity interval exercise session (HIIS) on next-day exercise performance. Eight male athletes performed three HIIS at 90%VO2max velocity followed by either a passive recovery (CON), CWI performed immediately post-exercise (CWI(0)) or CWI performed 3 h post-exercise (CWI(3)). Recovery trials were performed in a counter balanced manner. Participants then returned 24 h later and completed a muscle soreness and a totally quality recovery perception (TQRP) questionnaire, which was then followed by the Yoyo Intermittent Recovery Test [level 1] (YRT). Venous blood samples were collected pre-HIIS and pre-YRT to determine C-Reactive Protein (CRP) levels. Significantly more shuttles were performed during the YRT following CWI(0) compared to the CON trial (p=0.017, ES = 0. 8), while differences between the CWI(3) and the CON trials approached significance (p = 0.058, ES = 0.5). Performance on the YRT between the CWI(0) and CWI(3) trials were similar (p = 0.147, ES = 0. 3). Qualitative analyses demonstrated a 98% and 92% likely beneficial effect of CWI(0) and CWI(3) on next day performance, compared to CON, respectively, while CWI(0) resulted in a 79% likely benefit when compared to CWI(3). CRP values were significantly lower pre-YRT, compared to baseline, following CWI(0) (p = 0.0.36) and CWI(3) (p = 0.045), but were similar for CON (p = 0.157). Muscle soreness scores were similar between trials (p = 1.10), while TQRP scores were significantly lower for CON compared to CWI(0) (p = 0.002 ) and CWI(3) (p = 0.024). Immediate CWI resulted in superior next-day YRT performance compared to CON, while delayed (3 h) CWI was also likely to be beneficial. Qualitative analyses suggested that CWI(0) resulted in better performance than CWI(3). These results are important for athletes who do not have immediate access to CWI following exercise. Key pointsPerformance of cold water immersion as a recovery procedure following exercise is better than performing no recovery procedureAthletes, coaches and sport trainers should implement cold water immersion post-exercise irrespective of the time of administration.Where possible, cold water immersion should be performed immediately post-exercise to gain maximal recovery benefits.
Ihsan, Mohammed; Watson, Greig; Abbiss, Chris R
2016-08-01
Intense training results in numerous physiological perturbations such as muscle damage, hyperthermia, dehydration and glycogen depletion. Insufficient/untimely restoration of these physiological alterations might result in sub-optimal performance during subsequent training sessions, while chronic imbalance between training stress and recovery might lead to overreaching or overtraining syndrome. The use of post-exercise cold water immersion (CWI) is gaining considerable popularity among athletes to minimize fatigue and accelerate post-exercise recovery. CWI, through its primary ability to decrease tissue temperature and blood flow, is purported to facilitate recovery by ameliorating hyperthermia and subsequent alterations to the central nervous system (CNS), reducing cardiovascular strain, removing accumulated muscle metabolic by-products, attenuating exercise-induced muscle damage (EIMD) and improving autonomic nervous system function. The current review aims to provide a comprehensive and detailed examination of the mechanisms underpinning acute and longer term recovery of exercise performance following post-exercise CWI. Understanding the mechanisms will aid practitioners in the application and optimisation of CWI strategies to suit specific recovery needs and consequently improve athletic performance. Much of the literature indicates that the dominant mechanism by which CWI facilitates short term recovery is via ameliorating hyperthermia and consequently CNS mediated fatigue and by reducing cardiovascular strain. In contrast, there is limited evidence to support that CWI might improve acute recovery by facilitating the removal of muscle metabolites. CWI has been shown to augment parasympathetic reactivation following exercise. While CWI-mediated parasympathetic reactivation seems detrimental to high-intensity exercise performance when performed shortly after, it has been shown to be associated with improved longer term physiological recovery and day to day training performances. The efficacy of CWI for attenuating the secondary effects of EIMD seems dependent on the mode of exercise utilised. For instance, CWI application seems to demonstrate limited recovery benefits when EIMD was induced by single-joint eccentrically biased contractions. In contrast, CWI seems more effective in ameliorating effects of EIMD induced by whole body prolonged endurance/intermittent based exercise modalities.
[Physical activity diminishes aging-related decline of physical and cognitive performance].
Apor, Péter; Babai, László
2014-05-25
Aging-related decline of muscle force, walking speed, locomotor coordination, aerobic capacity and endurance exert prognostic impact on life expectancy. Proper use of training may diminish the aging process and it may improve the quality of life of elderly persons. This paper provides a brief summary on the impact of training on aging-related decline of physical and cognitive functions.
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.
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
Cell-phone use diminishes self-awareness of impaired driving.
Sanbonmatsu, David M; Strayer, David L; Biondi, Francesco; Behrends, Arwen A; Moore, Shannon M
2016-04-01
Multitasking diminishes the self-awareness of performance that is often essential for self-regulation and self-knowledge. Participants drove in a simulator while either talking or not talking on a hands-free cell phone. Following previous research, participants who talked on a cell phone made more serious driving errors than control participants who did not use a phone while driving. Control participants' assessments of the safeness of their driving and general ability to drive safely while distracted were negatively correlated with the actual number of errors made when they were driving. By contrast, cell-phone participants' assessments of the safeness of their driving and confidence in their driving abilities were uncorrelated with their actual errors. Thus, talking on a cell phone not only diminished the safeness of participants' driving, it diminished their awareness of the safeness of their driving.
Antonialli, Fernanda Colella; De Marchi, Thiago; Tomazoni, Shaiane Silva; Vanin, Adriane Aver; dos Santos Grandinetti, Vanessa; de Paiva, Paulo Roberto Vicente; Pinto, Henrique Dantas; Miranda, Eduardo Foschini; de Tarso Camillo de Carvalho, Paulo; Leal-Junior, Ernesto Cesar Pinto
2014-11-01
Recent studies with phototherapy have shown positive results in enhancement of performance and improvement of recovery when applied before exercise. However, several factors still remain unknown such as therapeutic windows, optimal treatment parameters, and effects of combination of different light sources (laser and LEDs). The aim of this study was to evaluate the effects of phototherapy with the combination of different light sources on skeletal muscle performance and post-exercise recovery, and to establish the optimal energy dose. A randomized, double-blinded, placebo-controlled trial with participation of 40 male healthy untrained volunteers was performed. A single phototherapy intervention was performed immediately after pre-exercise (baseline) maximum voluntary contraction (MVC) with a cluster of 12 diodes (4 of 905 nm lasers-0.3125 mW each, 4 of 875 nm LEDs-17.5 mW each, and 4 of 670 nm LEDs-15 mW each- manufactured by Multi Radiance Medical™) and dose of 10, 30, and 50 J or placebo in six sites of quadriceps. MVC, delayed onset muscle soreness (DOMS), and creatine kinase (CK) activity were analyzed. Assessments were performed before, 1 min, 1, 24, 48, 72, and 96 h after eccentric exercise protocol employed to induce fatigue. Phototherapy increased (p < 0.05) MVC was compared to placebo from immediately after to 96 h after exercise with 10 or 30 J doses (better results with 30 J dose). DOMS was significantly decreased compared to placebo (p < 0.05) with 30 J dose from 24 to 96 h after exercise, and with 50 J dose from immediately after to 96 h after exercise. CK activity was significantly decreased (p < 0.05) compared to placebo with all phototherapy doses from 1 to 96 h after exercise (except for 50 J dose at 96 h). Pre-exercise phototherapy with combination of low-level laser and LEDs, mainly with 30 J dose, significantly increases performance, decreases DOMS, and improves biochemical marker related to skeletal muscle damage.
Baeßler, Kaven; Junginger, Bärbel
2017-01-01
Background The aims of physiotherapy in stress incontinent women are to improve pelvic floor function and the continence mechanism including bladder neck support and urethral closure pressure. In Germany, traditional conservative treatment often includes gymnastic exercises with unclear effects on the bladder neck. The aim of this study was to sonographically assess bladder neck movements during selected exercises. Methods Fifteen healthy, continent women without previous vaginal births, who were able to voluntarily contract their pelvic floor muscels performed the shoulder bridge, the abdominal press, tiptoe and the Pilates clam exercises. The first set was performed without any additional instructions. During the second set directions were given to activate the pelvic floor before beginning each exercise and to maintain the contraction throughout the exercise. Bladder neck movement was measured on perineal ultrasound using a validated method with the pubic symphysis as a reference point. Results The median age of participants was 32 years, median BMI was 23. Eight women were nulliparous and seven had given birth to 1 – 2 children via caesarean section. When exercises were performed without voluntary pelvic floor contraction the bladder neck descended on average between 2.3 and 4.4 mm, and with pelvic floor contraction prior to the exercise only between 0.5 and 2.1 mm (p > 0.05 except for abdominal press p = 0.007). The Pilates clam exercise and toe stand stabilised the bladder neck most effectively. Discussion Bladder neck descent often occurs during pelvic floor gymnastic exercises as traditionally performed in Germany, and a voluntary pelvic floor contraction during the exercises does not necessarily prevent this. PMID:28757655
Skrip, Megan M; Seeram, Navindra P; Yuan, Tao; Ma, Hang; McWilliams, Scott R
2016-09-01
Physiological challenges during one part of the annual cycle can carry over and affect performance at a subsequent phase, and antioxidants could be one mediator of trade-offs between phases. We performed a controlled experiment with zebra finches to examine how songbirds use nutrition to manage trade-offs in antioxidant allocation between endurance flight and subsequent reproduction. Our treatment groups included (1) a non-supplemented, non-exercised group (control group) fed a standard diet with no exercise beyond that experienced during normal activity in an aviary; (2) a supplemented non-exercised group fed a water- and lipid-soluble antioxidant-supplemented diet with no exercise; (3) a non-supplemented exercised group fed a standard diet and trained to perform daily endurance flight for 6 weeks; and (4) a supplemented exercised group fed an antioxidant-supplemented diet and trained to perform daily flight for 6 weeks. After flight training, birds were paired within treatment groups for breeding. We analyzed eggs for lutein and vitamin E concentrations and the plasma of parents throughout the experiment for non-enzymatic antioxidant capacity and oxidative damage. Exercised birds had higher oxidative damage levels than non-exercised birds after flight training, despite supplementation with dietary antioxidants. Supplementation with water-soluble antioxidants decreased the deposition of lipid-soluble antioxidants into eggs and decreased yolk size. Flight exercise also lowered deposition of lutein, but not vitamin E, to eggs. These findings have important implications for future studies of wild birds during migration and other oxidative challenges. © 2016. Published by The Company of Biologists Ltd.
NASA Exercise Physiology and Countermeasures Project Overview
NASA Technical Reports Server (NTRS)
Loerch, Linda; Ploutz-Snyder, Lori
2009-01-01
Efficient exercise countermeasures are necessary to offset or minimize spaceflight-induced deconditioning and to maximize crew performance of mission tasks. These countermeasure protocols should use the fewest crew and vehicle resources. NASA s Exercise Physiology and Countermeasures (ExPC) Project works to identify, collect, interpret, and summarize evidence that results in effective exercise countermeasure protocols which protect crew health and performance during International Space Station (ISS) and future exploration-class missions. The ExPC and NASA s Human Research Program are sponsoring multiple studies to evaluate and improve the efficacy of spaceflight exercise countermeasures. First, the Project will measure maximal aerobic capacity (VO2max) during cycle ergometry before, during, and after ISS missions. Second, the Project is sponsoring an evaluation of a new prototype harness that offers improved comfort and increased loading during treadmill operations. Third, the Functional Tasks Test protocol will map performance of anticipated lunar mission tasks with physiologic systems before and after short and long-duration spaceflight, to target system contributions and the tailoring of exercise protocols to maximize performance. In addition to these studies that are actively enrolling crewmember participants, the ExPC is planning new studies that include an evaluation of a higher-intensity/lower-volume exercise countermeasure protocol aboard the ISS using the Advanced Resistive Exercise Device and second-generation treadmill, studies that evaluate bone loading during spaceflight exercise, and ground-based studies that focus on fitness for duty standards required to complete lunar mission tasks and for which exercise protocols need to protect. Summaries of these current and future studies and strategies will be provided to international colleagues for knowledge sharing and possible collaboration.
Artificial gravity exposure impairs exercise-related neurophysiological benefits.
Vogt, Tobias; Abeln, Vera; Strüder, Heiko K; Schneider, Stefan
2014-01-17
Artificial gravity (AG) exposure is suggested to counteract health deconditioning, theoretically complementing exercise during space habitations. Exercise-benefits on mental health are well documented (i.e. well-being, enhanced executive functions). Although AG is coherent for the integrity of fundamental physiological systems, the effects of its exposure on neurophysiological processes related to cognitive performance are poorly understood and therefore characterize the primary aim of this study. 16 healthy males participated in two randomly assigned sessions, AG and exercise (30minute each). Participants were exposed to AG at continuous +2Gz in a short-arm human centrifuge and performed moderate exercise (cycling ergometer). Using 64 active electrodes, resting EEG was recorded before (pre), immediately after (post), and 15min after (post15) each session. Alpha (7.5-12.5Hz) and beta frequencies (12.5-35.0Hz) were exported for analysis. Cognitive performance and mood states were assessed before and after each session. Cognitive performance improved after exercise (p<0.05), but not after AG. This was reflected by typical EEG patterns after exercise, however not after AG. Frontal alpha (post p<0.01, post15 p<0.001) and beta activity (post15 p<0.001) increased after AG compared to a decrease in frontal alpha (post15 p<0.05) and beta activity (post p<0.01) after exercise. Relaxed cortical states were indicated after exercise, but were less apparent after AG. Changes in mood states failed significance after both sessions. Summarized, the benefits to mental health, recorded after exercise, were absent after AG, indicating that AG might cause neurocognitive deconditioning. © 2013.
Choi, Kyuju; Bak, Jongwoo; Cho, Minkwon; Chung, Yijung
2016-09-01
[Purpose] This study investigated the changes in the muscle activities of the trunk and lower limbs of healthy adults during a one-legged bridge exercise using a sling, and with the addition of hip abduction. [Subjects and Methods] Twenty-seven healthy individuals participated in this study (14 males and 13 females). The participants were instructed to perform the bridge exercises under five different conditions. Trunk and lower limb muscle activation of the erector spinae (ES), external oblique (EO), gluteus maximus (GM), and biceps femoris (BF) was measured using surface electromyography. Data analysis was performed using the mean scores of three trials performed under each condition. [Results] There was a significant increase in bilateral EO and contralateral GM with the one-legged bridge compared with the one-legged bridge with sling exercise. Muscle activation of the ipsilateral GM and BF was significantly less during the one-legged bridge exercise compared to the one-legged bridge with sling exercise, and was significantly greater during the one-legged bridge with hip abduction compared to the one-legged bridge exercise. The muscle activation of the contralateral GM and BF was significantly greater with the one-legged bridge with hip abduction compared to the general bridge exercise. [Conclusion] With the one-legged bridge with hip abduction, the ipsilateral EO, GM and BF muscle activities were significantly greater than those of the one-legged bridge exercise. The muscle activation of all trunk and contralateral lower extremity muscles increased with the bridge with sling exercises compared with general bridge exercises.
NASA Astrophysics Data System (ADS)
Xia, Belle Selene; Liitiäinen, Elia
2017-11-01
The benefits of using online exercises have been analysed in terms of distance learning, automatic assessment and self-regulated learning. In this study, we have not found a direct proportional relationship between student performance in the course exercises that use online technologies and the exam grades. We see that the average submission rate to these online exercises is not positively correlated with the exercise points. Yet, our results confirm that doing exercises along supports student learning and skill accumulation equipping them with the knowledge of programming. While the student performance in programming courses is affected by factors such as prior background in programming, cognitive skills and the quality of teaching, completing the course exercises via learning-by-doing is an indispensable part of teaching. Based on the student feedback from the course survey, the students are highly satisfied with using online technologies as part of learning.
The Elite Athlete and Strenuous Exercise in Pregnancy.
Pivarnik, James M; Szymanski, Linda M; Conway, Michelle R
2016-09-01
Highly trained women continue to exercise during pregnancy, but there is little information available to guide them, and their health care providers, in how to maximize performance without jeopardizing the maternal-fetal unit. Available evidence focusing on average women who perform regular vigorous exercise suggests that this activity is helpful in preventing several maladies of pregnancy, with little to no evidence of harm. However, some studies have shown that there may be a limit to how intense an elite performer should exercise during pregnancy. Health care providers should monitor these women athletes carefully, to build trust and understanding.
Lundin-Olsson, Lillemor; Skelton, Dawn A.; Lundman, Berit; Rosendahl, Erik
2017-01-01
The objective of the study was to describe the views and experiences of participation in a high-intensity functional exercise (HIFE) program among older people with dementia in nursing homes. The study design was a qualitative interview study with 21 participants (15 women), aged 74–96, and with a Mini-Mental State Examination score of 10–23 at study start. The HIFE-program comprises exercises performed in functional weight-bearing positions and including movements used in everyday tasks. The exercise was individually designed, supervised in small groups in the nursing homes and performed during four months. Interviews were performed directly after exercise sessions and field notes about the sessions were recorded. Qualitative content analysis was used for analyses. The analysis revealed four themes: Exercise is challenging but achievable; Exercise gives pleasure and strength; Exercise evokes body memories; and Togetherness gives comfort, joy, and encouragement. The intense and tailored exercise, adapted to each participant, was perceived as challenging but achievable, and gave pleasure and improvements in mental and bodily strength. Memories of previous physical activities aroused and participants rediscovered bodily capabilities. Importance of individualized and supervised exercise in small groups was emphasized and created feelings of encouragement, safety, and coherence. The findings from the interviews reinforces the positive meaning of intense exercise to older people with moderate to severe dementia in nursing homes. The participants were able to safely adhere to and understand the necessity of the exercise. Providers of exercise should consider the aspects valued by participants, e.g. supervision, individualization, small groups, encouragement, and that exercise involved joy and rediscovery of body competencies. PMID:29149198
Lindelöf, Nina; Lundin-Olsson, Lillemor; Skelton, Dawn A; Lundman, Berit; Rosendahl, Erik
2017-01-01
The objective of the study was to describe the views and experiences of participation in a high-intensity functional exercise (HIFE) program among older people with dementia in nursing homes. The study design was a qualitative interview study with 21 participants (15 women), aged 74-96, and with a Mini-Mental State Examination score of 10-23 at study start. The HIFE-program comprises exercises performed in functional weight-bearing positions and including movements used in everyday tasks. The exercise was individually designed, supervised in small groups in the nursing homes and performed during four months. Interviews were performed directly after exercise sessions and field notes about the sessions were recorded. Qualitative content analysis was used for analyses. The analysis revealed four themes: Exercise is challenging but achievable; Exercise gives pleasure and strength; Exercise evokes body memories; and Togetherness gives comfort, joy, and encouragement. The intense and tailored exercise, adapted to each participant, was perceived as challenging but achievable, and gave pleasure and improvements in mental and bodily strength. Memories of previous physical activities aroused and participants rediscovered bodily capabilities. Importance of individualized and supervised exercise in small groups was emphasized and created feelings of encouragement, safety, and coherence. The findings from the interviews reinforces the positive meaning of intense exercise to older people with moderate to severe dementia in nursing homes. The participants were able to safely adhere to and understand the necessity of the exercise. Providers of exercise should consider the aspects valued by participants, e.g. supervision, individualization, small groups, encouragement, and that exercise involved joy and rediscovery of body competencies.
Cunha, Felipe A; Midgley, Adrian W; McNaughton, Lars R; Farinatti, Paulo T V
2016-02-01
The purpose of this study was to investigate excess postexercise oxygen consumption (EPOC) induced by isocaloric bouts of continuous and intermittent running and cycling exercise. This was a counterbalanced randomized cross-over study. Ten healthy men, aged 23-34yr, performed six bouts of exercise: (a) two maximal cardiopulmonary exercise tests for running and cycling to determine exercise modality-specific peak oxygen uptake (VO2peak); and (b) four isocaloric exercise bouts (two continuous bouts expending 400kcal and two intermittent bouts split into 2×200kcal) performed at 75% of the running and cycling oxygen uptake reserve. Exercise bouts were separated by 72h and performed in a randomized, counter-balanced order. The VO2 was monitored for 60-min postexercise and for 60-min during a control non-exercise day. The VO2 was significantly greater in all exercise conditions compared to the control session (P<0.001). The combined magnitude of the EPOC from the two intermittent bouts was significantly greater than that of the continuous cycling (mean difference=3.5L, P=0.001) and running (mean difference=6.4L, P<0.001). The exercise modality had a significant effect on net EPOC, where running elicited a higher net EPOC than cycling (mean difference=2.2L, P<0.001). Intermittent exercise increased the EPOC compared to a continuous exercise bout of equivalent energy expenditure. Furthermore, the magnitude of EPOC was influenced by exercise modality, with the greatest EPOC occurring with isocaloric exercise involving larger muscle mass (i.e., treadmill running vs. cycling). Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Kim, Yu-Ri; Yoo, Won-Gyu
2016-01-01
[Purpose] The purpose of this study was to investigate activities of the hip extensors and erector spinae during bridging exercise by using instruments with a laser pointer on the pelvic belt. [Subjects] Twelve subjects (age, 23 to 33 years) with non-specific low back pain volunteered for this study. [Methods] Subjects performed bridging exercises with and without trajectory exercises by using a laser pointer fixed to a pelvic strap. The erector spinae, gluteus maximus and hamstring activities with and without trajectory exercises using a laser pointer were recorded on using electromyography. [Results] Compared to the without laser pointer group, the group that underwent bridging with trajectory exercises using a laser pointer had significantly higher gluteus maximus activity and significantly lower erector spinae activity. Significantly higher gluteus maximus/erector spinae activity ratios were observed when performing trajectory exercises using a laser pointer during bridging exercises. [Conclusion] This result suggests that trajectory exercises using a laser pointer during a bridging exercise would be effective for improving gluteus maximus activity.
Kim, Jaeyuong; Park, Yunjin; Seo, Yonggon; Kang, Gyumin; Park, Sangseo; Cho, Hyeyoung; Moon, Hyunghoon; Kim, Myungki; Yu, Jaeho
2016-01-01
[Purpose] The purpose of this study was to investigate the effects of whole-body vibration exercise (WBVE) on isokinetic muscular function of the knee and jump performance depending on different squatting positions. [Subjects] The subjects were 12 healthy adult men who did not exercise regularly between the ages of 27 and 34. [Methods] WBVE was performed with high squat position (SP), middle SP, and low SP. Before and after the intervention, isokinetic muscular function of the knees and jump performance were measured. [Results] Knee flexion peak torque at 60°/s and total work at 180°/s were significantly increased after implementing WBVE. Jump height also significantly increased after completing the exercise at all positions in comparison with the pre-exercise programs. [Conclusion] The results of this study suggest that SP during WBVE is an important factor stimulating positive effects on muscular function. PMID:26957749
2012-01-01
The use of herbs as ergogenic aids in exercise and sport is not novel. Ginseng, caffeine, ma huang (also called 'Chinese ephedra'), ephedrine and a combination of both caffeine and ephedrine are the most popular herbs used in exercise and sports. It is believed that these herbs have an ergogenic effect and thus help to improve physical performance. Numerous studies have been conducted to investigate the effects of these herbs on exercise performance. Recently, researchers have also investigated the effects of Eurycoma longifolia Jack on endurance cycling and running performance. These investigators have reported no significant improvement in either cycling or running endurance after supplementation with this herb. As the number of studies in this area is still small, more studies should be conducted to evaluate and substantiate the effects of this herb on sports and exercise performance. For instance, future research on any herbs should take the following factors into consideration: dosage, supplementation period and a larger sample size. PMID:22738233
Lemos, Sandro; Figueiredo, Tiago; Marques, Silvio; Leite, Thalita; Cardozo, Diogo; Willardson, Jeffrey M; Simão, Roberto
2018-01-01
This study compared the effect of a strength training session performed at different exercise orders and rest intervals on blood pressure and heart rate variability (HRV). Fifteen trained men performed different upper body exercise sequences [large to small muscle mass (SEQA) and small to large muscle mass (SEQB)] in randomized order with rest intervals between sets and exercises of 40 or 90 seconds. Fifteen repetition maximum loads were tested to control the training intensity and the total volume load. The results showed, significant reductions for systolic blood pressure (SBP) for all sequences compared to baseline and, post-exercise: SEQA90 at 20, 30, 40, 50 and 60 minutes; SEQA40 and SEQB40 at 20 minutes and SEQB90 at 10, 20, 30, 40, 50 and 60 minutes. For diastolic blood pressure (DBP), significant reductions were found for three sequences compared to baseline and, post-exercise: SEQA90 and SEQA40 at 50 and 60 minutes; SEQB40 at 10, 30 and 60 minutes. For HRV, there were significant differences in frequency domain for all sequences compared to baseline. In conclusion, when performing upper body strength training sessions, it is suggested that 90 second rest intervals between sets and exercises promotes a post-exercise hypotensive response in SBP. The 40 second rest interval between sets and exercises was associated with greater cardiac stress, and might be contraindicated when working with individuals that exhibit symptoms of cardiovascular disease.
Factors affecting dance exercise performance in students at a special needs school.
Ito, Yukiko; Hiramoto, Izumi; Kodama, Hideya
2017-09-01
In Japan, dance exercise has been introduced as a compulsory element of health and physical education, but there is a considerable discrepancy in the levels of performance among students with intellectual disability (ID) at special needs schools. The aim of this study was therefore to identify the factors affecting the performance of dance exercise in students with ID. A 4 month dance exercise program was implemented for junior high school students at a special needs school, and the performance of 32 students at 22 sessions was assessed quantitatively according to calorie use during exercise and performance proficiency score. The measures were compared according to gender, age, body mass index, diagnosis, and development quotient (DQ) score. Performance in many students improved with repetition and reached the highest attainment level at around the third month. Male gender and older age had a significant positive impact on calorie use, whereas diagnosis of Down syndrome and higher DQ score had a significant positive impact on proficiency score. Four students with poor performance were all female students with autism. This study provides some possible explanations for differences in the levels of dance performance among students with ID. © 2017 Japan Pediatric Society.
A defence of medical paternalism: maximising patients' autonomy.
Komrad, M S
1983-01-01
All illness represents a state of diminished autonomy and therefore the doctor-patient relationship necessarily and justifiably involves a degree of medical paternalism argues the author, an American medical student. In a broad-ranging paper he discusses the concepts of autonomy and paternalism in the context of the doctor-patient relationship. Given the necessary diminution of autonomy which illness inflicts, a limited form of medical paternalism, aimed at restoring or maximising the patient's autonomy is entirely acceptable, and indeed fundamental to the relationship he argues. However, the exercise of this paternalism should be flexible and related to the current 'level of autonomy' of the patient himself. An editorial in this issue comments briefly on this paper. PMID:6834402
Park, J H; Brown, R L; Park, C R; Cohn, M; Chance, B
1988-01-01
The purpose of this study was to investigate whether genetically determined properties of muscle metabolism contribute to the exceptional physical endurance of world-class distance runners. ATP, phosphocreatine, inorganic phosphate, and pH were quantitatively determined by 31P nuclear magnetic resonance spectroscopy in the wrist flexor muscles of elite long-distance runners and sedentary control subjects. These muscles had not been exposed to any specific program of exercise training in either group of subjects. The "untrained" muscles were examined at rest, during two cycles of three grades of exercise, and in recovery. The flexor muscles of the athletes had higher concentrations of phosphocreatine and ATP than did those of the control subjects at rest and during exercise. The athletes' muscles possessed a higher capacity for generation of ATP by oxidative metabolism than did control subjects' muscles according to the following criteria: (i) high force output, 60% of maximum voluntary contraction, was more easily reached and better maintained in both exercise cycles; (ii) the ratio of inorganic phosphate to phosphocreatine rose less during exercise and recovered faster in the postexercise period; (iii) there was no loss of adenine nucleotides or total phosphate from the athletes' muscles but significant losses from the control subjects' muscles; and (iv) the pH decreased no more than 0.1 unit in the athletes' muscles during exercise, attesting to a relatively slow glycolysis and/or a rapid oxidation of lactate. In the muscles of the control subjects, on the other hand, the pH decreased nearly 0.4 unit early in the first exercise cycle, indicating a relatively fast glycolysis and/or slower oxidation of lactate. In the second exercise cycle, the pH returned to near normal in the control subjects' muscles, reflecting diminished lactate formation because of glycogen depletion and lactate washout by the high blood flow induced by exercise. By the end of the exercise program, the maximum voluntary contractile force for the control subjects had declined to less than 60% of the initial value. This decline could be explained best by exhaustion of the glycolytic contribution to muscle contraction. Therefore, the residual maximum strength provided a measure of the oxidative capacity to support contraction, as is discussed. In conclusion, we suggest that a greater oxidative capacity relative to glycolytic capacity for support of contraction in untrained muscle of world-class runners reflects a genetic endowment for physical endurance. Additional systemic effects of training cannot be completely excluded. 31P magnetic resonance spectroscopy provides a noninvasive method for assessing this endowment. PMID:3194388
2012-01-01
Background Sport drinks are ubiquitous within the recreational and competitive fitness and sporting world. Most are manufactured and artificially flavored carbohydrate-electrolyte beverages. Recently, attention has been given to coconut water, a natural alternative to manufactured sport drinks, with initial evidence indicating efficacy with regard to maintaining hydration. We compared coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. Methods Following a 60-minute bout of dehydrating treadmill exercise, 12 exercise-trained men (26.6 ± 5.7 yrs) received bottled water (BW), pure coconut water (VitaCoco®: CW), coconut water from concentrate (CWC), or a carbohydrate-electrolyte sport drink (SD) [a fluid amount based on body mass loss during the dehydrating exercise] on four occasions (separated by at least 5 days) in a random order, single blind (subject and not investigators), cross-over design. Hydration status (body mass, fluid retention, plasma osmolality, urine specific gravity) and performance (treadmill time to exhaustion; assessed after rehydration) were determined during the recovery period. Subjective measures of thirst, bloatedness, refreshed, stomach upset, and tiredness were also determined using a 5-point visual analog scale. Results Subjects lost approximately 1.7 kg (~2% of body mass) during the dehydrating exercise and regained this amount in a relatively similar manner following consumption of all conditions. No differences were noted between coconut water (CW or CWC) and SD for any measures of fluid retention (p > 0.05). Regarding exercise performance, no significant difference (p > 0.05) was noted between BW (11.9 ± 5.9 min), CW (12.3 ± 5.8 min), CWC (11.9 ± 6.0 min), and SD (12.8 ± 4.9 min). In general, subjects reported feeling more bloated and experienced greater stomach upset with the CW and CWC conditions. Conclusion All tested beverages are capable of promoting rehydration and supporting subsequent exercise. Little difference is noted between the four tested conditions with regard to markers of hydration or exercise performance in a sample of young, healthy men. Additional study inclusive of a more demanding dehydration protocol, as well as a time trial test as the measure of exercise performance, may more specifically determine the efficacy of these beverages on enhancing hydration and performance following dehydrating exercise. PMID:22257640
Hall, Eric E; Petruzzello, Steven J; Ekkekakis, Panteleimon; Miller, Paul C; Bixby, Walter R
2014-09-01
Performance in fitness tests could depend on factors beyond the bioenergetic and skeletomuscular systems, such as individual differences in preference for and tolerance of different levels of exercise-induced somatosensory stimulation. Although such individual-difference variables could play a role in exercise testing and prescription, they have been understudied. The purpose of these studies was to examine the relationships of self-reported preference for and tolerance of exercise intensity with performance in fitness tests. Participants in study I were 516 men and women volunteers from a campus community, and participants in study II were 42 men recruit firefighters undergoing a 6-week training program. Both the Preference and Tolerance scores exhibited significant relationships with performance in several fitness tests and with body composition and physical activity participation. Preference and Tolerance did not change after the training program in study II, despite improvements in objective and perceived fitness, supporting their conceptualization as dispositional traits. Preference and Tolerance scores could be useful not only in ameliorating the current understanding of the determinants of physical performance, but also in personalizing exercise prescriptions and, thus, delivering exercise experiences that are more pleasant, tolerable, and sustainable.
Marmeleira, José F; Godinho, Mário B; Fernandes, Orlando M
2009-01-01
The purpose of this study was to investigate the effects of participation in an exercise program on several abilities associated with driving performance in older adults. Thirty-two subjects were randomly assigned to either an exercise group (60-81 years, n=16) or a control group (60-82 years, n=16). The exercise program was planned to stress perceptive, cognitive, and physical abilities. It lasted 12 weeks with a periodicity of three sessions of 60 min per week. Assessments were conducted before and after the intervention on behavioral speed (in single- and dual-task conditions), visual attention, psychomotor performance, speed perception (time-to-contact), and executive functioning. Significant positive effects were found at 12-week follow-up resulting from participation in the exercise program. Behavioral speed improvements were found in reaction time, movement time, and response time (both in single- and dual-task conditions); visual attention improvements took place in speed processing and divided attention; psychomotor performance improvements occurred in lower limb mobility. These results showed that exercise is capable of enhancing several abilities relevant for driving performance and safety in older adults and, therefore, should be promoted.
Crowther, Robert G; Leicht, Anthony S; Spinks, Warwick L; Sangla, Kunwarjit; Quigley, Frank; Golledge, Jonathan
2012-01-01
The purpose of this study was to examine the effects of a 6-month exercise program on submaximal walking economy in individuals with peripheral arterial disease and intermittent claudication (PAD-IC). Participants (n = 16) were randomly allocated to either a control PAD-IC group (CPAD-IC, n = 6) which received standard medical therapy, or a treatment PAD-IC group (TPAD-IC; n = 10) which took part in a supervised exercise program. During a graded treadmill test, physiological responses, including oxygen consumption, were assessed to calculate walking economy during submaximal and maximal walking performance. Differences between groups at baseline and post-intervention were analyzed via Kruskal-Wallis tests. At baseline, CPAD-IC and TPAD-IC groups demonstrated similar walking performance and physiological responses. Postintervention, TPAD-IC patients demonstrated significantly lower oxygen consumption during the graded exercise test, and greater maximal walking performance compared to CPAD-IC. These preliminary results indicate that 6 months of regular exercise improves both submaximal walking economy and maximal walking performance, without significant changes in maximal walking economy. Enhanced walking economy may contribute to physiological efficiency, which in turn may improve walking performance as demonstrated by PAD-IC patients following regular exercise programs.
49 CFR 1.3 - Exercise of authority.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 1 2013-10-01 2013-10-01 false Exercise of authority. 1.3 Section 1.3... § 1.3 Exercise of authority. (a) In exercising powers and performing duties delegated by this part or..., the Assistant Secretaries, the Inspector General, and the Administrators exercise the powers and...
49 CFR 1.3 - Exercise of authority.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 1 2014-10-01 2014-10-01 false Exercise of authority. 1.3 Section 1.3... § 1.3 Exercise of authority. (a) In exercising powers and performing duties delegated by this part or..., the Assistant Secretaries, the Inspector General, and the Administrators exercise the powers and...
49 CFR 1.3 - Exercise of authority.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 1 2012-10-01 2012-10-01 false Exercise of authority. 1.3 Section 1.3... § 1.3 Exercise of authority. (a) In exercising powers and performing duties delegated by this part or..., the Assistant Secretaries, the Inspector General, and the Administrators exercise the powers and...
The Effects of ’Jet-Lag’ on Exercise Performance,
1983-05-11
The Effects of "Jet-Lag" on Exercise Performance ’ 6. PERFORMING ORG. REPORT NUMBER ~E AUTHOR(a) 6. CONTRACT OR GRANT NUMBER(&) James A. Vogel, Ph.D. 0... PERFORMING ORGANIZATION NAME AND ADDRESS SO. PROGRAM ELEMENT. PROJECT. TASK UAryResearch Isite of Ernetal AREA & WORK UNIT NUMBERS Medicine, Natick...entered In Block 20, If different from JU 7 193 IS. SUPPLEMENTARY NOTES To be published in Medicine Science in Sports and Exercise as a Symposium III
Govender, Roganie; Smith, Christina H; Taylor, Stuart A; Barratt, Helen; Gardner, Benjamin
2017-01-10
Dysphagia is a significant side-effect following treatment for head and neck cancers, yet poor adherence to swallowing exercises is frequently reported in intervention studies. Behaviour change techniques (BCTs) can be used to improve adherence, but no review to date has described the techniques or indicated which may be more associated with improved swallowing outcomes. A systematic review was conducted to identify behavioural strategies in swallowing interventions, and to explore any relationships between these strategies and intervention effects. Randomised and quasi-randomised studies of head and neck cancer patients were included. Behavioural interventions to improve swallowing were eligible provided a valid measure of swallowing function was reported. A validated and comprehensive list of 93 discrete BCTs was used to code interventions. Analysis was conducted via a structured synthesis approach. Fifteen studies (8 randomised) were included, and 20 different BCTs were each identified in at least one intervention. The BCTs identified in almost all interventions were: instruction on how to perform the behavior, setting behavioural goals and action planning. The BCTs that occurred more frequently in effective interventions, were: practical social support, behavioural practice, self-monitoring of behaviour and credible source for example a skilled clinician delivering the intervention. The presence of identical BCTs in comparator groups may diminish effects. Swallowing interventions feature multiple components that may potentially impact outcomes. This review maps the behavioural components of reported interventions and provides a method to consistently describe these components going forward. Future work may seek to test the most effective BCTs, to inform optimisation of swallowing interventions.
2014-01-01
Background The prevalence and consequences of musculoskeletal pain is considerable among healthcare workers, allegedly due to high physical work demands of healthcare work. Previous investigations have shown promising results of physical exercise for relieving pain among different occupational groups, but the question remains whether such physical exercise should be performed at the workplace or conducted as home-based exercise. Performing physical exercise at the workplace together with colleagues may be more motivating for some employees and thus increase adherence. On the other hand, physical exercise performed during working hours at the workplace may be costly for the employers in terms of time spend. Thus, it seems relevant to compare the efficacy of workplace- versus home-based training on musculoskeletal pain. This study is intended to investigate the effect of workplace-based versus home-based physical exercise on musculoskeletal pain among healthcare workers. Methods/Design This study was designed as a cluster randomized controlled trial performed at 3 hospitals in Copenhagen, Denmark. Clusters are hospital departments and hospital units. Cluster randomization was chosen to increase adherence and avoid contamination between interventions. Two hundred healthcare workers from 18 departments located at three different hospitals is allocated to 10 weeks of 1) workplace based physical exercise performed during working hours (using kettlebells, elastic bands and exercise balls) for 5 × 10 minutes per week and up to 5 group-based coaching sessions, or 2) home based physical exercise performed during leisure time (using elastic bands and body weight exercises) for 5 × 10 minutes per week. Both intervention groups will also receive ergonomic instructions on patient handling and use of lifting aides etc. Inclusion criteria are female healthcare workers working at a hospital. Average pain intensity (VAS scale 0-10) of the back, neck and shoulder (primary outcome) and physical exertion during work, social capital and work ability (secondary outcomes) is assessed at baseline and 10-week follow-up. Further, postural balance and mechanical muscle function is assessed during clinical examination at baseline and follow-up. Discussion This cluster randomized trial will investigate the change in self-rated average pain intensity in the back, neck and shoulder after either 10 weeks of physical exercise at the workplace or at home. Trial registration ClinicalTrials.gov (NCT01921764). PMID:24708570
Jakobsen, Markus D; Sundstrup, Emil; Brandt, Mikkel; Kristensen, Anne Zoëga; Jay, Kenneth; Stelter, Reinhard; Lavendt, Ebbe; Aagaard, Per; Andersen, Lars L
2014-04-07
The prevalence and consequences of musculoskeletal pain is considerable among healthcare workers, allegedly due to high physical work demands of healthcare work. Previous investigations have shown promising results of physical exercise for relieving pain among different occupational groups, but the question remains whether such physical exercise should be performed at the workplace or conducted as home-based exercise. Performing physical exercise at the workplace together with colleagues may be more motivating for some employees and thus increase adherence. On the other hand, physical exercise performed during working hours at the workplace may be costly for the employers in terms of time spend. Thus, it seems relevant to compare the efficacy of workplace- versus home-based training on musculoskeletal pain. This study is intended to investigate the effect of workplace-based versus home-based physical exercise on musculoskeletal pain among healthcare workers. This study was designed as a cluster randomized controlled trial performed at 3 hospitals in Copenhagen, Denmark. Clusters are hospital departments and hospital units. Cluster randomization was chosen to increase adherence and avoid contamination between interventions. Two hundred healthcare workers from 18 departments located at three different hospitals is allocated to 10 weeks of 1) workplace based physical exercise performed during working hours (using kettlebells, elastic bands and exercise balls) for 5 × 10 minutes per week and up to 5 group-based coaching sessions, or 2) home based physical exercise performed during leisure time (using elastic bands and body weight exercises) for 5 × 10 minutes per week. Both intervention groups will also receive ergonomic instructions on patient handling and use of lifting aides etc. Inclusion criteria are female healthcare workers working at a hospital. Average pain intensity (VAS scale 0-10) of the back, neck and shoulder (primary outcome) and physical exertion during work, social capital and work ability (secondary outcomes) is assessed at baseline and 10-week follow-up. Further, postural balance and mechanical muscle function is assessed during clinical examination at baseline and follow-up. This cluster randomized trial will investigate the change in self-rated average pain intensity in the back, neck and shoulder after either 10 weeks of physical exercise at the workplace or at home. ClinicalTrials.gov (NCT01921764).
Caritá, Renato Aparecido Corrêa; Greco, Camila Coelho; Denadai, Benedito Sérgio
2014-01-01
The purpose of this study was to determine both the independent and additive effects of prior heavy-intensity exercise and pacing strategies on the VO2 kinetics and performance during high-intensity exercise. Fourteen endurance cyclists (VO2max = 62.8±8.5 mL.kg−1.min−1) volunteered to participate in the present study with the following protocols: 1) incremental test to determine lactate threshold and VO2max; 2) four maximal constant-load tests to estimate critical power; 3) six bouts of exercise, using a fast-start (FS), even-start (ES) or slow-start (SS) pacing strategy, with and without a preceding heavy-intensity exercise session (i.e., 90% critical power). In all conditions, the subjects completed an all-out sprint during the final 60 s of the test as a measure of the performance. For the control condition, the mean response time was significantly shorter (p<0.001) for FS (27±4 s) than for ES (32±5 s) and SS (32±6 s). After the prior exercise, the mean response time was not significantly different among the paced conditions (FS = 24±5 s; ES = 25±5 s; SS = 26±5 s). The end-sprint performance (i.e., mean power output) was only improved (∼3.2%, p<0.01) by prior exercise. Thus, in trained endurance cyclists, an FS pacing strategy does not magnify the positive effects of priming exercise on the overall VO2 kinetics and short-term high-intensity performance. PMID:24740278
Men exhibit greater fatigue resistance than women in alternated bench press and leg press exercises.
Monteiro, Estêvão R; Steele, James; Novaes, Jefferson S; Brown, Amanda F; Cavanaugh, Mark T; Vingren, Jakob L; Behm, David G
2017-11-17
The purpose of this study was to evaluate the influence of sex, exercise order, and rest interval on neuromuscular fatigue resistance for an alternated strength training sequence of bench press (BP) and leg press (LP) exercises. Twelve women and 16 men, both recreationally trained, performed four sessions in a random order: 1) BP followed by LP with three-minutes rest (BP+LP with rest), 2) LP followed by BP with three-minutes rest (LP+BP with rest), 3) BP followed by LP without rest interval (BP+LP no rest), and 4) LP followed by BP without rest interval (LP+BP no rest). Participants performed four sets with 100% of 10RM load to concentric failure with the goal of completing the maximum number of repetitions in both exercises. The fatigue index was analyzed from the first and last sets of each exercise bout. A main effect for sex showed that women exhibited 25.5% (p=0.001) and 24.5% (p=0.001) greater BP and LP fatigue than men respectively when performing 10RM. Men exhibited greater BP (p<0.0001; 34.1%) and LP (p<0.0001; 30.5%) fatigue resistance when a rest period was provided. Men did not show an exercise order effect for BP fatigue and exhibited greater (p=0.0003; 14.5%) LP fatigue resistance when BP was performed first. The present study demonstrated the greater fatigue resistance of men when performing 10RM BP and LP exercises. Since men tend to experience less fatigue with the second exercise in the exercise pairing, women's training programs should be adjusted to ensure they do not parallel men's resistance training programs.
The Effect of Krill Oil Supplementation on Exercise Performance and Markers of Immune Function
Da Boit, Mariasole; Mastalurova, Ina; Brazaite, Goda; McGovern, Niall; Thompson, Keith; Gray, Stuart Robert
2015-01-01
Background Krill oil is a rich source of the long-chain n-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which may alter immune function after exercise. The aim of the study was to determine the effects of krill oil supplementation on post exercise immune function and performance. Methods Nineteen males and 18 females (age: 25.8 ± 5.3 years; mean ± S.D.) were randomly assigned to 2 g/day of krill oil (n = 18) or placebo (n = 19) supplementation for 6 weeks. A maximal incremental exercise test and cycling time trial (time to complete set amount of work) were performed pre-supplementation with the time trial repeated post-supplementation. Blood samples collected pre- and post- supplementation at rest, and immediately, 1 and 3h post-exercise. Plasma IL-6 and thiobarbituric acid reactive substances (TBARS) concentrations and, erythrocyte fatty acid composition were measured. Natural killer (NK) cell cytotoxic activity and peripheral blood mononuclear cell (PBMC) IL-2, IL-4, IL-10, IL-17 and IFNγ production were also measured. Results No effects of gender were noted for any variable. PBMC IL-2 and NK cell cytotoxic activity were greater (P < 0.05) 3h post exercise in the krill oil compared to the control group. Plasma IL-6 and TBARS, PBMC IL-4, IL-10, IL-17 and IFNγ production, along with performance and physiological measures during exercise, were not different between groups. Conclusion Six weeks of krill oil supplementation can increase PBMC IL-2 production and NK cell cytotoxic activity 3h post-exercise in both healthy young males and females. Krill oil does not modify exercise performance. PMID:26407095
Brown, A K; Liu-Ambrose, T; Tate, R; Lord, S R
2009-08-01
To determine the effect of a general group-based exercise programme on cognitive performance and mood among seniors without dementia living in retirement villages. Randomised controlled trial. Four intermediate care and four self-care retirement village sites in Sydney, Australia. 154 seniors (19 men, 135 women; age range 62 to 95 years), who were residents of intermediate care and self-care retirement facilities. Participants were randomised to one of three experimental groups: (1) a general group-based exercise (GE) programme composed of resistance training and balance training exercises; (2) a flexibility exercise and relaxation technique (FR) programme; or (3) no-exercise control (NEC). The intervention groups (GE and FR) participated in 1-hour exercise classes twice a week for a total period of 6 months. Using standard neuropsychological tests, we assessed cognitive performance at baseline and at 6-month re-test in three domains: (1) fluid intelligence; (2) visual, verbal and working memory; and (3) executive functioning. We also assessed mood using the Geriatric Depression Scale (GDS) and the Positive and Negative Affect Schedule (PANAS). The GE programme significantly improved cognitive performance of fluid intelligence compared with FR or NEC. There were also significant improvements in the positive PANAS scale within both the GE and FR groups and an indication that the two exercise programmes reduced depression in those with initially high GDS scores. Our GE programme significantly improved cognitive performance of fluid intelligence in seniors residing in retirement villages compared with our FR programme and the NEC group. Furthermore, both group-based exercise programmes were beneficial for certain aspects of mood within the 6-month intervention period.
Electromyographic analyses of muscle pre-activation induced by single joint exercise.
Júnior, Valdinar A R; Bottaro, Martim; Pereira, Maria C C; Andrade, Marcelino M; P Júnior, Paulo R W; Carmo, Jake C
2010-01-01
To investigate whether performing a low-intensity, single-joint exercises for knee extensors was an efficient strategy for increasing the number of motor units recruited in the vastus lateralis muscle during a subsequent multi-joint exercises. Nine healthy male participants (23.33+/-3.46 yrs) underwent bouts of exercise in which knee extension and 45 degrees , and leg press exercises were performed in sequence. In the low-intensity bout (R30), 15 unilateral knee extensions were performed, followed by 15 repetitions of the leg presses at 30% and 60% of one maximum repetition load (1-MR), respectively. In the high-intensity bout (R60), the same sequence was performed, but the applied load was 60% of 1-MR for both exercises. A single set of 15 repetitions of the leg press at 60% of 1-MR was performed as a control exercise (CR). The surface electromyographic signals of the vastus lateralis muscle were recorded by means of a linear electrode array. The root mean square (RMS) values were determined for each repetition of the leg press, and linear regressions were calculated from these results. The slopes of the straight lines obtained were then normalized using the linear coefficients of the regression equations and compared using one-way ANOVAs for repeated measures. The slopes observed in the CR were significantly lower than those in the R30 and R60 (p<0.05). The results indicated that the recruitment of motor units was more effective when a single-joint exercise preceded the multi-joint exercise. Article registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) under the number ACTRN12609000413224.
Lin, Tzu-Wei; Chen, Shean-Jen; Huang, Tung-Yi; Chang, Chia-Yuan; Chuang, Jih-Ing; Wu, Fong-Sen; Kuo, Yu-Min; Jen, Chauying J
2012-01-01
Different exercise paradigms show differential effects on various forms of memory. We hypothesize that the differential effects of exercises on memory performance are caused by different neuroplasticity changes in relevant brain regions in response to different exercise trainings. We examined the effects of treadmill running (TR) and wheel running (WR) on the Pavlovian fear conditioning task that assesses learning and memory performance associated with the amygdala (cued conditioning) and both the amygdala and hippocampus (contextual conditioning). The skeletal muscle citrate synthase activity, an indicator of aerobic capacity, was elevated in rats received 4 w of TR, but not WR. While both TR and WR elevated the contextual conditional response, only TR facilitated the cued conditional response. Using a single-neuron labeling technique, we found that while both TR and MR enlarged the dendritic field and increased the spine density in hippocampal CA3 neurons, only TR showed these effects in basolateral amygdalar neurons. Moreover, both types of exercise upregulated synaptic proteins (i.e., TrkB and SNAP-25) in the hippocampus; however only TR showed similar effects in the amygdala. Injection of K252a, a TrkB kinase inhibitor, in the dorsal hippocampus or basolateral amygdala abolished the exercise-facilitated contextual or cued fear learning and memory performance, respectively, regardless of the types of exercise. In summary, our results supported that different types of exercise affect the performance of learning and memory via BDNF-TrkB signaling and neuroplasticity in specific brain regions. The brain region-specific neuronal adaptations are possibly induced by various levels of intensity/stress elicited by different types of exercise. Copyright © 2011 Elsevier Inc. All rights reserved.
Cardiorespiratory deconditioning with static and dynamic leg exercise during bed rest.
Stremel, R W; Convertino, V A; Bernauer, E M; Greenleaf, J E
1976-12-01
Bed rest deconditioning was assessed in seven healthy men (19-22 yr) following three 14-day periods of controlled activity during recumbency by measuring submaximal and maximal oxygen uptake (VO2), ventilation (VE), heart rate, and plasma volume. Exercise regimens were performed in the supine position and included a) two 30-min periods daily of intermittent static exercise at 21% of maximal leg extension force, and b) two 30-min periods of dynamic bicycle ergometer exercise daily at 68% of VO2max. No prescribed exercise was performed during the third bed rest period. Compared with their respective pre-bed rest control values, VO2max decreased (P less than 0.05) under all exercise conditions; -12.3% with no exercise, -9.2% with dynamic exercise, but only -4.8% with static exercise. Maximal heart rate was increased by 3.3% to 4.9% (P less than 0.05) under the three exercise conditions, while plasma volume decreased (P less than 0.05) -15.1% with no exercise and -10.1% with static, but only -7.8% (NS) with dynamic exercise. Since neither the static nor dynamic exercise training regimes minimized the changes in all the variables studied, some combination of these two types of exercise may be necessary for maximum protection from the effects of the bed deconditioning.
Role of beta-alanine supplementation on muscle carnosine and exercise performance.
Artioli, Guilherme Giannini; Gualano, Bruno; Smith, Abbie; Stout, Jeffrey; Lancha, Antonio Herbert
2010-06-01
In this narrative review, we present and discuss the current knowledge available on carnosine and beta-alanine metabolism as well as the effects of beta-alanine supplementation on exercise performance. Intramuscular acidosis has been attributed to be one of the main causes of fatigue during intense exercise. Carnosine has been shown to play a significant role in muscle pH regulation. Carnosine is synthesized in skeletal muscle from the amino acids l-histidine and beta-alanine. The rate-limiting factor of carnosine synthesis is beta-alanine availability. Supplementation with beta-alanine has been shown to increase muscle carnosine content and therefore total muscle buffer capacity, with the potential to elicit improvements in physical performance during high-intensity exercise. Studies on beta-alanine supplementation and exercise performance have demonstrated improvements in performance during multiple bouts of high-intensity exercise and in single bouts of exercise lasting more than 60 s. Similarly, beta-alanine supplementation has been shown to delay the onset of neuromuscular fatigue. Although beta-alanine does not improve maximal strength or VO2max, some aspects of endurance performance, such as anaerobic threshold and time to exhaustion, can be enhanced. Symptoms of paresthesia may be observed if a single dose higher than 800 mg is ingested. The symptoms, however, are transient and related to the increase in plasma concentration. They can be prevented by using controlled release capsules and smaller dosing strategies. No important side effect was related to the use of this amino acid so far. In conclusion, beta-alanine supplementation seems to be a safe nutritional strategy capable of improving high-intensity anaerobic performance.
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.
Aerobic Exercise During Encoding Impairs Hippocampus-Dependent Memory.
Soga, Keishi; Kamijo, Keita; Masaki, Hiroaki
2017-08-01
We investigated how aerobic exercise during encoding affects hippocampus-dependent memory through a source memory task that assessed hippocampus-independent familiarity and hippocampus-dependent recollection processes. Using a within-participants design, young adult participants performed a memory-encoding task while performing a cycling exercise or being seated. The subsequent retrieval phase was conducted while sitting on a chair. We assessed behavioral and event-related brain potential measures of familiarity and recollection processes during the retrieval phase. Results indicated that source accuracy was lower for encoding with exercise than for encoding in the resting condition. Event-related brain potential measures indicated that the parietal old/new effect, which has been linked to recollection processing, was observed in the exercise condition, whereas it was absent in the rest condition, which is indicative of exercise-induced hippocampal activation. These findings suggest that aerobic exercise during encoding impairs hippocampus-dependent memory, which may be attributed to inefficient source encoding during aerobic exercise.
Ozcelik, Oguz; Ozkan, Yusuf; Algul, Sermin; Colak, Ramis
2015-01-01
The aim of this study was to determine and compare the effects of weight loss achieved through orlistat therapy alone or a combination of orlistat and an aerobic exercise training program on aerobic fitness and body composition in obese females. Twenty-eight obese patients were randomly assigned to receive 12-week treatment with hypocaloric diet-orlistat or diet-orlistat-exercise. Each participant performed an incremental ramp exercise test every 4 weeks to measure aerobic fitness. Fourteen participants performed continuous exercise (approximately 45 minutes per session) at a work rate corresponding to the anaerobic threshold three times per week. A decrease in the fat mass to body weight ratio of 3.8% (P=0.006) was observed at the end of the 12 weeks in the orlistat group, while a decrease of 9.5% (P=0.001) was seen in the orlistat-exercise group. Maximal exercise capacity increased by 46.5% in the orlistat-exercise group and by 19.5% in the orlistat group. While orlistat therapy resulted in an improvement in body composition and aerobic fitness at the end of the 12-week period, its combination with exercise training provided improvements in the same parameters within the first 4 weeks of the study. These additional beneficial effects of combining aerobic exercise with orlistat therapy are important with regards to obesity-associated risk factors.
An Analysis of Muscle Activities of Healthy Women during Pilates Exercises in a Prone Position.
Kim, Bo-In; Jung, Ju-Hyeon; Shim, Jemyung; Kwon, Hae-Yeon; Kim, Haroo
2014-01-01
[Purpose] This study analyzed the activities of the back and hip muscles during Pilates exercises conducted in a prone position. [Subjects] The subjects were 18 healthy women volunteers who had practiced at a Pilates center for more than three months. [Methods] The subjects performed three Pilates exercises. To examine muscle activity during the exercises, 8-channel surface electromyography (Noraxon USA, Inc., Scottsdale, AZ) was used. The surface electrodes were attached to the bilateral latissimus dorsi muscle, multifidus muscle, gluteus maximus, and semitendinous muscle. Three Pilates back exercises were compared: (1) double leg kick (DLK), (2) swimming (SW), and (3) leg beat (LB). Electrical muscle activation was normalized to maximal voluntary isometric contraction. Repeated measures analysis of variance was performed to assess the differences in activation levels among the exercises. [Results] The activity of the multifidus muscle was significantly high for the SW (52.3±11.0, 50.9±9.8) and LB exercises(51.8±12.8, 48.3±13.9) and the activity of the semitendinosus muscle was higher for the LB exercise (49.2±8.7, 52.9±9.3) than for the DLK and SW exercises. [Conclusion] These results may provide basic material for when Pilates exercises are performed in a prone position and may be useful information on clinical Pilates for rehabilitation programs.
The Effects of Acute Exercise on Memory and Brain-Derived Neurotrophic Factor (BDNF).
Etnier, Jennifer L; Wideman, Laurie; Labban, Jeffrey D; Piepmeier, Aaron T; Pendleton, Daniel M; Dvorak, Kelly K; Becofsky, Katie
2016-08-01
Acute exercise benefits cognition, and some evidence suggests that brain-derived neurotrophic factor (BDNF) plays a role in this effect. The purpose of this study was to explore the dose-response relationship between exercise intensity, memory, and BDNF. Young adults completed 3 exercise sessions at different intensities relative to ventilator threshold (Vt) (VO 2max , Vt - 20%, Vt + 20%). For each session, participants exercised for approximately 30 min. Following exercise, they performed the Rey Auditory Verbal Learning Test (RAVLT) to assess short-term memory, learning, and long-term memory recall. Twenty-four hours later, they completed the RAVLT recognition trial, which provided another measure of long-term memory. Blood was drawn before exercise, immediately postexercise, and after the 30-min recall test. Results indicated that long-term memory as assessed after the 24-hr delay differed as a function of exercise intensity with the largest benefits observed following maximal intensity exercise. BDNF data showed a significant increase in response to exercise; however, there were no differences relative to exercise intensity and there were no significant associations between BDNF and memory. Future research is warranted so that we can better understand how to use exercise to benefit cognitive performance.
Pettersson, Henrik; Faager, Gun; Westerdahl, Elisabeth
2015-09-01
Breathing exercises after cardiac surgery are often performed in a sitting position. It is unknown whether oxygenation would be better in the standing position. The aim of this study was to evaluate oxygenation and subjective breathing ability during sitting vs standing performance of deep breathing exercises on the second day after cardiac surgery. Patients undergoing coronary artery bypass grafting (n = 189) were randomized to sitting (controls) or standing. Both groups performed 3 × 10 deep breaths with a positive expiratory pressure device. Peripheral oxygen saturation was measured before, directly after, and 15 min after the intervention. Subjective breathing ability, blood pressure, heart rate, and pain were assessed. Oxygenation improved significantly in the standing group compared with controls directly after the breathing exercises (p < 0.001) and after 15 min rest (p = 0.027). The standing group reported better deep breathing ability compared with controls (p = 0.004). A slightly increased heart rate was found in the standing group (p = 0.047). After cardiac surgery, breathing exercises with positive expiratory pressure, performed in a standing position, significantly improved oxygenation and subjective breathing ability compared with sitting performance. Performance of breathing exercises in the standing position is feasible and could be a valuable treatment for patients with postoperative hypoxaemia.
Chan, Ding-Cheng; Chang, Chirn-Bin; Han, Der-Sheng; Hong, Cian-Hui; Hwang, Jawl-Shan; Tsai, Keh-Sung; Yang, Rong-Sen
2017-10-26
The deterioration of the musculoskeletal system imposes significant impact on physical activity. Exercise is an important strategy which minimizes these changes. It is not clear which type of exercise provides better improvement on low physical performance, low muscle mass and low strength of sarcopenia. We aim to develop an integrated care (IC) model and compare its relative efficacy in limb fat free mass, muscle strength, and physical performance with low extremities exercise (LEE) in community dwelling older adults with high risk of fractures (Fracture Risk Assessment Tool (FRAX ® )) ≧3% for hip fracture, ≧20% for major osteoporotic fracture or 1-min osteoporosis risk test (≧1 point) or fall (≧2 falls in previous year). Patients were assigned randomized to participate in either IC or LEE group (n = 55 each) for 3 months. All participants received education including home-based exercise. The IC group consisted of different modalities of exercise while the LEE group performed machine-based low extremities exercise. Fat free mass, muscle strength, and physical performance were measured at their baseline and 3-months follow-up. Mean age was 73.8 ± 7 years with 69.1% women. Entire cohort demonstrated significant increment in fat free mass, muscle strength (4 indicators) and physical performance (3 indicators). However, between group differences were not significant. With regular supervise exercise; both groups are equally effective in decreasing fat mass and increasing physical performance, muscle mass and strength. However, the IC group required fewer resources and thus more financially feasible in a community setting. Copyright © 2017. Published by Elsevier B.V.
Morris, David M; Huot, Joshua R; Jetton, Adam M; Collier, Scott R; Utter, Alan C
2015-10-01
Dehydration has been shown to hinder performance of sustained exercise in the heat. Consuming fluids before exercise can result in hyperhydration, delay the onset of dehydration during exercise and improve exercise performance. However, humans normally drink only in response to thirst, which does not result in hyperhydration. Thirst and voluntary fluid consumption have been shown to increase following oral ingestion or infusion of sodium into the bloodstream. We measured the effects of acute sodium ingestion on voluntary water consumption and retention during a 2-hr hydration period before exercise. Subjects then performed a 60-min submaximal dehydration ride (DR) followed immediately by a 200 kJ performance time trial (PTT) in a warm (30 °C) environment. Water consumption and retention during the hydration period was greater following sodium ingestion (1380 ± 580 mL consumed, 821 ± 367 ml retained) compared with placebo (815 ± 483 ml consumed, 244 ± 402 mL retained) and no treatment (782 ± 454 ml consumed, 148 ± 289 mL retained). Dehydration levels following the DR were significantly less after sodium ingestion (0.7 ± 0.6%) compared with placebo (1.3 ± 0.7%) and no treatment (1.6 ± 0.4%). Time to complete the PTT was significantly less following sodium consumption (773 ± 158 s) compared with placebo (851 ± 156 s) and no treatment (872 ± 190 s). These results suggest that voluntary hyperhydration can be induced by acute consumption of sodium and has a favorable effect on hydration status and performance during subsequent exercise in the heat.
Bieuzen, François; Pournot, Hervé; Roulland, Rémy; Hausswirth, Christophe
2012-01-01
Electric muscle stimulation has been suggested to enhance recovery after exhaustive exercise by inducing an increase in blood flow to the stimulated area. Previous studies have failed to support this hypothesis. We hypothesized that the lack of effect shown in previous studies could be attributed to the technique or device used. To investigate the effectiveness of a recovery intervention using an electric blood-flow stimulator on anaerobic performance and muscle damage in professional soccer players after intermittent, exhaustive exercise. Randomized controlled clinical trial. National Institute of Sport, Expertise, and Performance (INSEP). Twenty-six healthy professional male soccer players. The athletes performed an intermittent fatiguing exercise followed by a 1-hour recovery period, either passive or using an electric blood-flow stimulator (VEINOPLUS). Participants were randomly assigned to a group before the experiment started. Performances during a 30-second all-out exercise test, maximal vertical countermovement jump, and maximal voluntary contraction of the knee extensor muscles were measured at rest, immediately after the exercise, and 1 hour and 24 hours later. Muscle enzymes indicating muscle damage (creatine kinase, lactate dehydrogenase) and hematologic profiles were analyzed before and 1 hour and 24 hours after the intermittent fatigue exercise. The electric-stimulation group had better 30-second all-out performances at 1 hour after exercise (P = .03) in comparison with the passive-recovery group. However, no differences were observed in muscle damage markers, maximal vertical countermovement jump, or maximal voluntary contraction between groups (P > .05). Compared with passive recovery, electric stimulation using this blood-flow stimulator improved anaerobic performance at 1 hour postintervention. No changes in muscle damage markers or maximal voluntary contraction were detected. These responses may be considered beneficial for athletes engaged in sports with successive rounds interspersed with short, passive recovery periods.
Intensive exercise training suppresses testosterone during bed rest
NASA Technical Reports Server (NTRS)
Wade, C. E.; Stanford, K. I.; Stein, T. P.; Greenleaf, J. E.
2005-01-01
Spaceflight and prolonged bed rest (BR) alter plasma hormone levels inconsistently. This may be due, in part, to prescription of heavy exercise as a countermeasure for ameliorating the adverse effects of disuse. The initial project was to assess exercise programs to maintain aerobic performance and leg strength during BR. The present study evaluates the effect of BR and the performance of the prescribed exercise countermeasures on plasma steroid levels. In a 30-day BR study of male subjects, the efficacy of isotonic (ITE, n = 7) or isokinetic exercise (IKE, n = 7) training was evaluated in contrast to no exercise (n = 5). These exercise countermeasures protected aerobic performance and leg strength successfully. BR alone (no-exercise group) did not change steroidogenesis, as assessed by the plasma concentrations of cortisol, progesterone, aldosterone, and free (FT) and total testosterone (TT). In the exercise groups, both FT and TT were decreased (P < 0.05): FT during IKE from 24 +/- 1.7 to 18 +/- 2.0 pg/ml and during ITE from 21 +/- 1.5 to 18 +/- 1 pg/ml, and TT during IKE from 748 +/- 68 to 534 +/- 46 ng/dl and during ITE from 565 +/- 36 to 496 +/- 38 ng/dl. The effect of intensive exercise countermeasures on plasma testosterone was not associated with indexes of overtraining. The reduction in plasma testosterone associated with both the IKE and ITE countermeasures during BR supports our hypothesis that intensive exercise countermeasures may, in part, contribute to changes in plasma steroid concentrations during spaceflight.
Demura, Shinichi; Morishita, Koji; Yamada, Takayoshi; Yamaji, Shunsuke; Komatsu, Miho
2011-11-01
L-Ornithine plays an important role in ammonia metabolism via the urea cycle. This study aimed to examine the effect of L-ornithine hydrochloride ingestion on ammonia metabolism and performance after intermittent maximal anaerobic cycle ergometer exercise. Ten healthy young adults (age, 23.8 ± 3.9 year; height, 172.3 ± 5.5 cm; body mass, 67.7 ± 6.1 kg) with regular training experience ingested L-ornithine hydrochloride (0.1 g/kg, body mass) or placebo after 30 s of maximal cycling exercise. Five sets of the same maximal cycling exercise were conducted 60 min after ingestion, and maximal cycling exercise was conducted after a 15 min rest. The intensity of cycling exercise was based on each subject's body mass (0.74 N kg(-1)). Work volume (watt), peak rpm (rpm) before and after intermittent maximal ergometer exercise and the following serum parameters were measured before ingestion, immediately after exercise and 15 min after exercise: ornithine, ammonia, urea, lactic acid and glutamate. Peak rpm was significantly greater with L-ornithine hydrochloride ingestion than with placebo ingestion. Serum ornithine level was significantly greater with L-ornithine hydrochloride ingestion than with placebo ingestion immediately and 15 min after intermittent maximal cycle ergometer exercise. In conclusion, although maximal anaerobic performance may be improved by L-ornithine hydrochloride ingestion before intermittent maximal anaerobic cycle ergometer exercise, the above may not depend on increase of ammonia metabolism with L-ornithine hydrochloride.
The 'sensory tolerance limit': A hypothetical construct determining exercise performance?
Hureau, Thomas J; Romer, Lee M; Amann, Markus
2018-02-01
Neuromuscular fatigue compromises exercise performance and is determined by central and peripheral mechanisms. Interactions between the two components of fatigue can occur via neural pathways, including feedback and feedforward processes. This brief review discusses the influence of feedback and feedforward mechanisms on exercise limitation. In terms of feedback mechanisms, particular attention is given to group III/IV sensory neurons which link limb muscle with the central nervous system. Central corollary discharge, a copy of the neural drive from the brain to the working muscles, provides a signal from the motor system to sensory systems and is considered a feedforward mechanism that might influence fatigue and consequently exercise performance. We highlight findings from studies supporting the existence of a 'critical threshold of peripheral fatigue', a previously proposed hypothesis based on the idea that a negative feedback loop operates to protect the exercising limb muscle from severe threats to homeostasis during whole-body exercise. While the threshold theory remains to be disproven within a given task, it is not generalisable across different exercise modalities. The 'sensory tolerance limit', a more theoretical concept, may address this issue and explain exercise tolerance in more global terms and across exercise modalities. The 'sensory tolerance limit' can be viewed as a negative feedback loop which accounts for the sum of all feedback (locomotor muscles, respiratory muscles, organs, and muscles not directly involved in exercise) and feedforward signals processed within the central nervous system with the purpose of regulating the intensity of exercise to ensure that voluntary activity remains tolerable.
Pasquini, Guido; Vannetti, Federica; Molino-Lova, Raffaele
2015-05-01
During maximal incremental exercise, the ability to work in the anaerobic condition, expressed by the respiratory exchange ratio, is associated with physical performance. Further, peak respiratory exchange ratio is regarded as the best non-invasive measure of a patient's actual exercise effort. This study examined whether ability to work in the anaerobic condition is also associated with physical performance in submaximal constant work rate exercise. A total of 75 older patients (51 men, 24 women), mean age 71.1 years (standard deviation 6.7 years), who had recently undergone cardiac surgery, performed cardiopulmonary exercise testing in a 6-min walk test before and after rehabilitation. The distance walked, steady-state oxygen uptake, carbon dioxide output and respiratory exchange ratio increased significantly after rehabilitation (p < 0.001 for all). In multivariable models predicting the distance walked before and after rehabilitation, higher steady-state respiratory exchange ratio was independently associated with longer distance (p < 0.001 for both). In older patients receiving post-acute cardiac rehabilitation the ability to work in the anaerobic condition is associated with physical performance in submaximal constant work rate exercises. Thus the steady-state respiratory exchange ratio might be regarded as a measure of the patient's actual exercise effort. This information may prove useful in customizing exercise prescription and assessing the effects of rehabilitation.
Effects of high intensity exercise on isoelectric profiles and SDS-PAGE mobility of erythropoietin.
Voss, S; Lüdke, A; Romberg, S; Schänzer, E; Flenker, U; deMarees, M; Achtzehn, S; Mester, J; Schänzer, W
2010-06-01
Exercise induced proteinuria is a common phenomenon in high performance sports. Based on the appearance of so called "effort urines" in routine doping analysis the purpose of this study was to investigate the influence of exercise induced proteinuria on IEF profiles and SDS-PAGE relative mobility values (rMVs) of endogenous human erythropoietin (EPO). Twenty healthy subjects performed cycle-ergometer exercise until exhaustion. VO (2)max, blood lactate, urinary proteins and urinary creatinine were analysed to evaluate the exercise performance and proteinuria. IEF and SDS-PAGE analyses were performed to test for differences in electrophoretic behaviour of the endogenous EPO before and after exercise. All subjects showed increased levels of protein/creatinine ratio after performance (8.8+/-5.2-26.1+/-14.4). IEF analysis demonstrated an elevation of the relative amount of basic band areas (13.9+/-11.3-36.4+/-12.6). Using SDS-PAGE analysis we observed a decrease in rMVs after exercise and no shift in direction of the recombinant human EPO (rhEPO) region (0.543+/-0.013-0.535+/-0.012). Following identification criteria of the World Anti Doping Agency (WADA) all samples were negative. The implementation of the SDS-PAGE method represents a good solution to distinguish between results influenced by so called effort urines and results of rhEPO abuse. Thus this method can be used to confirm adverse analytical findings.
Not only cardiovascular, but also coordinative exercise increases hippocampal volume in older adults
Niemann, Claudia; Godde, Ben; Voelcker-Rehage, Claudia
2014-01-01
Cardiovascular activity has been shown to be positively associated with gray and white matter volume of, amongst others, frontal and temporal brain regions in older adults. This is particularly true for the hippocampus, a brain structure that plays an important role in learning and memory, and whose decline has been related to the development of Alzheimer’s disease. In the current study, we were interested in whether not only cardiovascular activity but also other types of physical activity, i.e., coordination training, were also positively associated with the volume of the hippocampus in older adults. For this purpose we first collected cross-sectional data on “metabolic fitness” (cardiovascular fitness and muscular strength) and “motor fitness” (e.g., balance, movement speed, fine coordination). Second, we performed a 12-month randomized controlled trial. Results revealed that motor fitness but not metabolic fitness was associated with hippocampal volume. After the 12-month intervention period, both, cardiovascular and coordination training led to increases in hippocampal volume. Our findings suggest that a high motor fitness level as well as different types of physical activity were beneficial to diminish age-related hippocampal volume shrinkage or even increase hippocampal volume. PMID:25165446
Does power indicate capacity? 30-s Wingate anaerobic test vs. maximal accumulated O2 deficit.
Minahan, C; Chia, M; Inbar, O
2007-10-01
The purpose of this study was to evaluate the relationship between anaerobic power and capacity. Seven men and seven women performed a 30-s Wingate Anaerobic Test on a cycle ergometer to determine peak power, mean power, and the fatigue index. Subjects also cycled at a work rate predicted to elicit 120 % of peak oxygen uptake to exhaustion to determine the maximal accumulated O (2) deficit. Peak power and the maximal accumulated O (2) deficit were significantly correlated (r = 0.782, p = 0.001). However, when the absolute difference in exercise values between groups (men and women) was held constant using a partial correlation, the relationship diminished (r = 0.531, p = 0.062). In contrast, we observed a significant correlation between fatigue index and the maximal accumulated O (2) deficit when controlling for gender (r = - 0.597, p = 0.024) and the relationship remained significant when values were expressed relative to active muscle mass. A higher anaerobic power does not indicate a greater anaerobic capacity. Furthermore, we suggest that the ability to maintain power output during a 30-s cycle sprint is related to anaerobic capacity.
How Does Exercise Benefit Performance on Cognitive Tests in Primary-School Pupils?
ERIC Educational Resources Information Center
Hill, Liam J. B.; Williams, Justin H. G.; Aucott, Lorna; Thomson, Jenny; Mon-Williams, Mark
2011-01-01
Aim: We have previously demonstrated improved cognitive performance after a classroom-based exercise regime. In this study, we examined the reproducibility of this effect in a more socio-economically diverse sample and also investigated whether cognitive benefits of exercise were moderated by body mass index (BMI) or symptoms of…
Effects of prior warm-up regime on severe-intensity cycling performance.
Burnley, Mark; Doust, Jonathan H; Jones, Andrew M
2005-05-01
The purpose of the present study was to determine the effect of three different warm-up regimes on cycling work output during a 7-min performance trial. After habituation to the experimental methods, 12 well-trained cyclists completed a series of 7-min performance trials, involving 2 min of constant-work rate exercise at approximately 90% VO2max and a further 5 min during which subjects attempted to maximize power output. This trial was performed without prior intervention and 10 min after bouts of moderate, heavy, or sprint exercise in a random order. Pulmonary gas exchange was measured breath by breath during all performance trials. At the onset of the performance trial, baseline blood [lactate] was significantly elevated after heavy and sprint but not moderate exercise (mean +/- SD: control, 1.0 +/- 0.3 mM; moderate, 1.0 +/- 0.2 mM; heavy, 3.0 +/- 1.1 mM; sprint, 5.9 +/- 1.5 mM). All three interventions significantly increased the amplitude of the primary VO2 response (control, 2.59 +/- 0.28 L x min(-1); moderate, 2.69 +/- 0.27 L x min(-1); heavy, 2.78 +/- 0.26 L x min(-1); sprint, 2.78 +/- 0.30 L x min(-1)). Mean power output was significantly increased by prior moderate and heavy exercise but not significantly reduced after sprint exercise (control, 330 +/- 42 W; moderate, 338 +/- 39 W; heavy, 339 +/- 42 W; sprint, 324 +/- 45 W). These data indicate that priming exercise performed in the moderate- and heavy-intensity domains can improve severe-intensity cycling performance by ~2-3%, the latter condition doing so despite a mild lactacidosis being present at exercise onset.
Casa, Douglas J.
1999-01-01
Objective: To acquaint athletic trainers with the numerous interrelated components that must be considered when assisting athletes who exercise in hot environments. Useful guidelines to maximize performance and minimize detrimental health consequences are presented. Data Sources: The databases MEDLINE and SPORT Discus were searched from 1980 to 1999, with the terms. “body cooling,” “dehydration,” “exercise,” “heat illnesses,” “heat,” “fluid replacement,” “acclimatization,” “hydration,” “rehydration,” “performance,” and “intravenous,” among others. Data Synthesis: This paper provides an in-depth look at issues regarding physiologic and performance considerations related to rehydration, strategies to maximize rehydration, modes of rehydration, health consequences of exercise in the heat, heat acclimatization, body cooling techniques, and practice and competition modifications. Conclusions/Recommendations: Athletic trainers have a responsibility to ensure that athletes who exercise in hot environments are prepared to do so in an optimal manner and to act properly to avoid the potentially harmful heat illnesses that can result from exercise in the heat. PMID:16558573