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Sample records for inspiratory muscle strength

  1. Diagnostic methods to assess inspiratory and expiratory muscle strength*

    PubMed Central

    Caruso, Pedro; de Albuquerque, André Luis Pereira; Santana, Pauliane Vieira; Cardenas, Leticia Zumpano; Ferreira, Jeferson George; Prina, Elena; Trevizan, Patrícia Fernandes; Pereira, Mayra Caleffi; Iamonti, Vinicius; Pletsch, Renata; Macchione, Marcelo Ceneviva; Carvalho, Carlos Roberto Ribeiro

    2015-01-01

    Impairment of (inspiratory and expiratory) respiratory muscles is a common clinical finding, not only in patients with neuromuscular disease but also in patients with primary disease of the lung parenchyma or airways. Although such impairment is common, its recognition is usually delayed because its signs and symptoms are nonspecific and late. This delayed recognition, or even the lack thereof, occurs because the diagnostic tests used in the assessment of respiratory muscle strength are not widely known and available. There are various methods of assessing respiratory muscle strength during the inspiratory and expiratory phases. These methods are divided into two categories: volitional tests (which require patient understanding and cooperation); and non-volitional tests. Volitional tests, such as those that measure maximal inspiratory and expiratory pressures, are the most commonly used because they are readily available. Non-volitional tests depend on magnetic stimulation of the phrenic nerve accompanied by the measurement of inspiratory mouth pressure, inspiratory esophageal pressure, or inspiratory transdiaphragmatic pressure. Another method that has come to be widely used is ultrasound imaging of the diaphragm. We believe that pulmonologists involved in the care of patients with respiratory diseases should be familiar with the tests used in order to assess respiratory muscle function.Therefore, the aim of the present article is to describe the advantages, disadvantages, procedures, and clinical applicability of the main tests used in the assessment of respiratory muscle strength. PMID:25972965

  2. Determinants of inspiratory muscle strength in healthy humans.

    PubMed

    Brown, Peter I; Johnson, Michael A; Sharpe, Graham R

    2014-06-01

    We investigated (1) the relationship between the baseline and inspiratory muscle training (IMT) induced increase in maximal inspiratory pressure (P(I,max)) and (2) the relative contributions of the inspiratory chest wall muscles and the diaphragm (P(oes)/P(di)) to P(I,max) prior to and following-IMT. Experiment 1: P(I,max) was assessed during a Müeller manoeuvre before and after 4-wk IMT (n=30). Experiment 2: P(I,max) and the relative contribution of the inspiratory chest wall muscles to the diaphragm (P(oes)/P(di)) were assessed during a Müeller manoeuvre before and after 4-wk IMT (n=20). Experiment 1: P(I,max) increased 19% (P<0.01) post-IMT and was correlated with baseline P(I,max) (r=-0.373, P<0.05). Experiment 2: baseline P(I,max) was correlated with P(oe)/P(di) (r=0.582, P<0.05) and after IMT PI,max increased 22% and Poe/Pdi increased 5% (P<0.05). In conclusion, baseline P(I,max) and the contribution of the chest wall inspiratory muscles relative to the diaphragm affect, in part, baseline and IMT-induced P(I,max). Great care should be taken when designing future IMT studies to ensure parity in the between-subject baseline P(I,max). PMID:24598814

  3. Pre-operative inspiratory muscle training preserves postoperative inspiratory muscle strength following major abdominal surgery – a randomised pilot study

    PubMed Central

    Kulkarni, SR; Fletcher, E; McConnell, AK; Poskitt, KR; Whyman, MR

    2010-01-01

    INTRODUCTION The aim of this pilot study was to assess the effect of pre-operative inspiratory muscle training (IMT) on respiratory variables in patients undergoing major abdominal surgery. PATIENTS AND METHODS Respiratory muscle strength (maximum inspiratory [MIP] and expiratory [MEP] mouth pressure) and pulmonary functions were measured at least 2 weeks before surgery in 80 patients awaiting major abdominal surgery. Patients were then allocated randomly to one of four groups (Group A, control; Group B, deep breathing exercises; Group C, incentive spirometry; Group D, specific IMT). Patients in groups B, C and D were asked to train twice daily, each session lasting 15 min, for at least 2 weeks up to the day before surgery. Outcome measurements were made immediately pre-operatively and postop-eratively. RESULTS In groups A, B and C, MIP did not increase from baseline to pre-operative assessments. In group D, MIP increased from 51.5 cmH2O (median) pre-training to 68.5 cmH2O (median) post-training pre-operatively (P < 0.01). Postoperatively, groups A, B and C showed a fall in MIP from baseline (P < 0.01, P < 0.01) and P = 0.06, respectively). No such significant reduction in postoperative MIP was seen in group D (P = 0.36). CONCLUSIONS Pre-operative specific IMT improves MIP pre-operatively and preserves it postoperatively. Further studies are required to establish if this is associated with reduced pulmonary complications. PMID:20663275

  4. [Evaluation of the inspiratory muscle strength using the nasal pressure of the sniff].

    PubMed

    Fitting, J W; Héritier, F; Uldry, C

    1996-10-01

    The measurement of oesophageal pressure during maximal sniffs (Poes sniff) is useful to assess inspiratory muscle strength. The aim of this study was to develop a noninvasive test of inspiratory muscle strength based on the sniff manoeuvre. The sniff nasal inspiratory pressure (SNIP) was measured through a plug occluding one nostril during sniffs performed through the contralateral nostril. In 10 normal subjects and in 12 patients with neuromuscular or skeletal disorders, the SNIP reliably reflected the Poes sniff. Nasal mucosa congestion was induced in four normal subjects by nebulization of increasing doses of histamine. The SNIP accurately reflected Poes sniff when nasal congestion was moderate, but failed to do so when congestion was severe. Reference values of SNIP were established in a group of 160 healthy subjects aged 20-80 years. For both men and women, SNIP was negatively correlated with age, and was similar in the sitting and in the supine positions. SNIP was higher than maximal inspiratory pressure (P1 max) in most subjects, but the wide limits of agreement showed that these two methods are not interchangeable but complementary. The SNIP represents a useful noninvasive test of inspiratory muscle strength. PMID:8999474

  5. [The effects of pulmonary rehabilitation combined with inspiratory muscle training on pulmonary function and inspiratory muscle strength in elderly patients with chronic obstructive pulmonary disease].

    PubMed

    Sudo, E; Ohga, E; Matsuse, T; Teramoto, S; Nagase, T; Katayama, H; Takizawa, H; Tanaka, M; Kikuchi, N; Kakurai, S; Fukuchi, Y; Ouchi, Y

    1997-11-01

    It has been suggested that pulmonary rehabilitation compined with inspiratory muscle training (IMT) might improve pulmonary function and respiratory muscle strength in elderly patients with chronic obstructive pulmonary disease (COPD). To test this hypothesis, inspiratory muscle strength (PImax), expiratory muscle strength (PEmax) and resting pulmonary function were measured in 13 elderly patients with COPD (aged 70.3 +/- 2.7 years). Inspiratory muscle training (IMT) was performed for 15 min twice a day, using a pressure threshold device, for a total of 12 weeks. The inspiratory threshold was set at 15% of maximal inspiratory pressure (PImax) for each individual. Pulmonary rehabilitation was performed for 12-h sessions over a 12-week period. Patients with COPD were assigned randomly to two groups: pulmonary rehabilitation combined with IMT (group A) (n = 7), and conventional pulmonary rehabilitation only (group B) (n = 6). Functional residual capacity (FRC) decreased significantly from 4.3 +/- 0.4 L at baseline to 3.9 +/- 0.4 L after rehabilitation (p < 0.01), Vp significantly increased from 4.6 +/- 0.8 L/sec at baseline to 5.1 +/- 0.7 L/sec after rehabilitation (p < 0.05) and the PImax increased significantly from 51.5 +/- 5.4 cmH2O at baseline to 80.9 +/- 7.0 cmH2O after rehabilitation (p < 0.02) in group A. However, these variables did not change in group B. There was no improvement in the 10-minutes walking distance of group A, but there was a significant increase in that of group B. It can be concluded that pulmonary rehabilitation combined with IMT improves pulmonary function and inspiratory muscle strength in elderly patients with COPD. PMID:9483953

  6. Inspiratory muscle training: integrative review.

    PubMed

    Padula, Cynthia A; Yeaw, Evelyn

    2006-01-01

    This article provides a critical review of inspiratory muscle training (IMT) in chronic obstructive pulmonary disease (COPD). Although extensive research on IMT has accumulated, its benefits have been debated, primarily because of methodological limitations of studies. Using relevant key words, multiple databases were searched from 1966. Selected studies used PImax (maximal inspiratory pressure) as an outcome variable. Overall, research demonstrated that a standard protocol of 30% or higher for a duration of 20 to 30 minutes per day for 10 to 12 weeks improves dyspnea and inspiratory strength and endurance with either inspiratory resistive or inspiratory threshold training. Regardless of method, IMT protocols for people with COPD and inspiratory muscle weakness and dyspnea are generally safe, feasible, and effective. Patient selectivity and study of subgroups are recommended. PMID:17190116

  7. Inspiratory muscle strength training improves weaning outcome in failure to wean patients: a randomized trial

    PubMed Central

    2011-01-01

    Introduction Most patients are readily liberated from mechanical ventilation (MV) support, however, 10% - 15% of patients experience failure to wean (FTW). FTW patients account for approximately 40% of all MV days and have significantly worse clinical outcomes. MV induced inspiratory muscle weakness has been implicated as a contributor to FTW and recent work has documented inspiratory muscle weakness in humans supported with MV. Methods We conducted a single center, single-blind, randomized controlled trial to test whether inspiratory muscle strength training (IMST) would improve weaning outcome in FTW patients. Of 129 patients evaluated for participation, 69 were enrolled and studied. 35 subjects were randomly assigned to the IMST condition and 34 to the SHAM treatment. IMST was performed with a threshold inspiratory device, set at the highest pressure tolerated and progressed daily. SHAM training provided a constant, low inspiratory pressure load. Subjects completed 4 sets of 6-10 training breaths, 5 days per week. Subjects also performed progressively longer breathing trials daily per protocol. The weaning criterion was 72 consecutive hours without MV support. Subjects were blinded to group assignment, and were treated until weaned or 28 days. Results Groups were comparable on demographic and clinical variables at baseline. The IMST and SHAM groups respectively received 41.9 ± 25.5 vs. 47.3 ± 33.0 days of MV support prior to starting intervention, P = 0.36. The IMST and SHAM groups participated in 9.7 ± 4.0 and 11.0 ± 4.8 training sessions, respectively, P = 0.09. The SHAM group's pre to post-training maximal inspiratory pressure (MIP) change was not significant (-43.5 ± 17.8 vs. -45.1 ± 19.5 cm H2O, P = 0.39), while the IMST group's MIP increased (-44.4 ± 18.4 vs. -54.1 ± 17.8 cm H2O, P < 0.0001). There were no adverse events observed during IMST or SHAM treatments. Twenty-five of 35 IMST subjects weaned (71%, 95% confidence interval (CI) = 55% to 84

  8. Immediate effect of manual therapy on respiratory functions and inspiratory muscle strength in patients with COPD

    PubMed Central

    Yilmaz Yelvar, Gul Deniz; Çirak, Yasemin; Demir, Yasemin Parlak; Dalkilinç, Murat; Bozkurt, Bülent

    2016-01-01

    Objective The objective of this study was to investigate the immediate effect of manual therapy (MT) on respiratory functions and inspiratory muscle strength in patients with COPD. Participants and methods Thirty patients with severe COPD (eight females and 22 males; mean age 62.4±6.8 years) referred to pulmonary physiotherapy were included in this study. The patients participated in a single session of MT to measure the short-term effects. The lung function was measured using a portable spirometer. An electronic pressure transducer was used to measure respiratory muscle strength. Heart rate, breathing frequency, and oxygen saturation were measured with a pulse oximeter. For fatigue and dyspnea perception, the modified Borg rating of perceived exertion scale was used. All measurements were taken before and immediately after the first MT session. The ease-of-breathing visual analog scale was used for rating patients’ symptoms subjectively during the MT session. Results There was a significant improvement in the forced expiratory volume in the first second, forced vital capacity, and vital capacity values (P<0.05). The maximal inspiratory pressure and maximal expiratory pressure values increased significantly after MT, compared to the pre-MT session (P<0.05). There was a significant decrease in heart rate, respiratory rate (P<0.05), and dyspnea and fatigue perception (P<0.05). Conclusion A single MT session immediately improved pulmonary function, inspiratory muscle strength, and oxygen saturation and reduced dyspnea, fatigue, and heart and respiratory rates in patients with severe COPD. MT should be added to pulmonary rehabilitation treatment as a new alternative that is fast acting and motivating in patients with COPD. PMID:27382271

  9. Inspiratory muscle training in Morquio's syndrome: a case study.

    PubMed

    Savci, Sema; Ozturk, Melda; Inal-Ince, Deniz; Gultekin, Zuhal; Arikan, Hulya; Sivri, H Serap Kalkanoglu

    2006-12-01

    We reported a case of MPS IV A presented with dyspnea on exertion and respiratory muscle weakness. The patient underwent inspiratory muscle training (IMT) using threshold loading for 18 weeks. After 6 weeks of initial IMT, aerobic exercise training consisting of walking was added to the treatment program. Inspiratory muscle strength increased 70%, and 6-minute walk test (6MWT) distance increased to 47 m. With the inclusion of aerobic exercise training, additional increases in inspiratory muscle strength (7%) and 6MWT distance (26.5 m) were obtained. Exertional dyspnea improved from severe to slight after 6 weeks of IMT, and to very slight after additional 12 weeks of combined aerobic training and IMT. Health-related quality of life improved especially in social function, emotional function, vitality, and physical role. In conclusion, inspiratory muscles can be trained with the improvement of muscle strength in a patient with Morquio's syndrome. PMID:16998925

  10. Effects of Inspiratory and Expiratory Muscle Training in Normal Subjects

    PubMed Central

    Kurosawa, Hajime; Kohzuki, Masahiro

    2005-01-01

    The present study aimed to clarify the effects of inspiratory muscle training (IMT) and expiratory muscle training (EMT) on ventilatory muscle strength, pulmonary function and responses during exercise testing. Young healthy women were randomly assigned to 3 groups: IMT (n=16); EMT (n=16); or untrained normal controls (NC, n=8). Subjects in the IMT and EMT groups trained for 15 minutes twice daily over 2 weeks at loads of 30% maximal inspiratory and expiratory muscle strength, respectively. Ventilatory muscle strength (maximal inspiratory and expiratory muscle strength; PImax and PEmax, respectively), pulmonary function and progressive exercise testing was performed. Both PImax and PEmax increased in the IMT group, and PEmax increased in the EMT group. Neither trained group demonstrated any change in pulmonary function or peak values during exercise testing. In the IMT group, exercise-induced increases in heart rate, oxygen uptake (VO2/kg) and rating of perceived exertion (RPE) decreased with training, as did increases in VO2/kg and RPE in the EMT group. The increased ventilatory muscle strength in both IMT and EMT groups might improve ventilatory efficacy during exercise, and increased inspiratory muscle strength might facilitate oxygen delivery through improved circulatory responses. PMID:25792941

  11. Inspiratory muscle training in patients with chronic obstructive pulmonary disease: structural adaptation and physiologic outcomes.

    PubMed

    Ramirez-Sarmiento, Alba; Orozco-Levi, Mauricio; Guell, Rosa; Barreiro, Esther; Hernandez, Nuria; Mota, Susana; Sangenis, Merce; Broquetas, Joan M; Casan, Pere; Gea, Joaquim

    2002-12-01

    The present study was aimed at evaluating the effects of a specific inspiratory muscle training protocol on the structure of inspiratory muscles in patients with chronic obstructive pulmonary disease. Fourteen patients (males, FEV1, 24 +/- 7% predicted) were randomized to either inspiratory muscle or sham training groups. Supervised breathing using a threshold inspiratory device was performed 30 minutes per day, five times a week, for 5 consecutive weeks. The inspiratory training group was subjected to inspiratory loading equivalent to 40 to 50% of their maximal inspiratory pressure. Biopsies from external intercostal muscles and vastus lateralis (control muscle) were taken before and after the training period. Muscle samples were processed for morphometric analyses using monoclonal antibodies against myosin heavy chain isoforms I and II. Increases in both the strength and endurance of the inspiratory muscles were observed in the inspiratory training group. This improvement was associated with increases in the proportion of type I fibers (by approximately 38%, p < 0.05) and in the size of type II fibers (by approximately 21%, p < 0.05) in the external intercostal muscles. No changes were observed in the control muscle. The study demonstrates that inspiratory training induces a specific functional improvement of the inspiratory muscles and adaptive changes in the structure of external intercostal muscles. PMID:12406842

  12. The effect of exercise training with an additional inspiratory load on inspiratory muscle fatigue and time-trial performance.

    PubMed

    McEntire, Serina J; Smith, Joshua R; Ferguson, Christine S; Brown, Kelly R; Kurti, Stephanie P; Harms, Craig A

    2016-08-01

    The purpose was to determine the effect of moderate-intensity exercise training (ET) on inspiratory muscle fatigue (IMF) and if an additional inspiratory load during ET (ET+IL) would further improve inspiratory muscle strength, IMF, and time-trial performance. 15 subjects were randomly divided to ET (n=8) and ET+IL groups (n=7). All subjects completed six weeks of exercise training three days/week at ∼70%V̇O2peak for 30min. The ET+IL group breathed through an inspiratory muscle trainer (15% PImax) during exercise. 5-mile, and 30-min time-trials were performed pre-training, weeks three and six. Inspiratory muscle strength increased (p<0.05) for both groups to a similar (p>0.05) extent. ET and ET+IL groups improved (p<0.05) 5-mile time-trial performance (∼10% and ∼18%) and the ET+IL group was significantly faster than ET at week 6. ET and ET+IL groups experienced less (p<0.05) IMF compared to pre-training following the 5-mile time-trial. In conclusion, these data suggest ET leads to less IMF, ET+IL improves inspiratory muscle strength and IMF, but not different than ET alone. PMID:27195511

  13. Effects of inspiratory muscle training on resistance to fatigue of respiratory muscles during exhaustive exercise.

    PubMed

    Segizbaeva, M O; Timofeev, N N; Donina, Zh A; Kur'yanovich, E N; Aleksandrova, N P

    2015-01-01

    The aim of this study was to assess the effect of inspiratory muscle training (IMT) on resistance to fatigue of the diaphragm (D), parasternal (PS), sternocleidomastoid (SCM) and scalene (SC) muscles in healthy humans during exhaustive exercise. Daily inspiratory muscle strength training was performed for 3 weeks in 10 male subjects (at a pressure threshold load of 60% of maximal inspiratory pressure (MIP) for the first week, 70% of MIP for the second week, and 80% of MIP for the third week). Before and after training, subjects performed an incremental cycle test to exhaustion. Maximal inspiratory pressure and EMG-analysis served as indices of inspiratory muscle fatigue assessment. The before-to-after exercise decreases in MIP and centroid frequency (fc) of the EMG (D, PS, SCM, and SC) power spectrum (P<0.05) were observed in all subjects before the IMT intervention. Such changes were absent after the IMT. The study found that in healthy subjects, IMT results in significant increase in MIP (+18%), a delay of inspiratory muscle fatigue during exhaustive exercise, and a significant improvement in maximal work performance. We conclude that the IMT elicits resistance to the development of inspiratory muscles fatigue during high-intensity exercise. PMID:25248344

  14. Inspiratory muscle training in the patient with neuromuscular disease.

    PubMed

    McCool, F D; Tzelepis, G E

    1995-11-01

    Pulmonary complications due to respiratory muscle dysfunction are commonly a source of morbidity and mortality in patients with neuromuscular diseases. This review discusses the adverse effects of respiratory muscle weakness on pulmonary mechanics and examines the role that inspiratory muscle training may play in reversing pulmonary dysfunction in these individuals. In asymptomatic persons, it is well established that the inspiratory muscles can be trained to increase both force and endurance. In patients with neuromuscular diseases, the effects of training protocols on force and endurance are more controversial. This article reviews seven studies that have evaluated respiratory muscle training in a total of 75 patients with varied neuromuscular disorders. Training regimens included breathing through inspiratory resistive loads and isocapnic hyperpnea. Despite methodologic differences among studies, investigators have generally shown that the inspiratory muscles are similar to other skeletal muscle groups in that they can be trained for both force and endurance in these patients. The training-related improvements in inspiratory muscle performance are more pronounced in patients who are less severely affected by their disease. In those patients who have disease to the extent that they are already retaining carbon dioxide, there is little change in force or endurance with training. In these individuals, the inspiratory muscles may already be working at a level sufficiently severe to provide a training stimulus with each breath. No adverse effects of inspiratory muscle training were reported. Inspiratory muscle training can improve force and endurance in patients with neuromuscular weakness.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7480122

  15. High-intensity inspiratory muscle training in COPD.

    PubMed

    Hill, K; Jenkins, S C; Philippe, D L; Cecins, N; Shepherd, K L; Green, D J; Hillman, D R; Eastwood, P R

    2006-06-01

    The aim of the present study was to investigate the effects of an interval-based high-intensity inspiratory muscle training (H-IMT) programme on inspiratory muscle function, exercise capacity, dyspnoea and health-related quality of life (QoL) in subjects with chronic obstructive pulmonary disease. A double-blind randomised controlled trial was performed. Sixteen subjects (11 males, mean forced expiratory volume in one second (FEV(1)) 37.4+/-12.5%) underwent H-IMT performed at the highest tolerable inspiratory threshold load (increasing to 101% of baseline maximum inspiratory pressure). Seventeen subjects (11 males, mean FEV(1 )36.5+/-11.5%) underwent sham inspiratory muscle training (S-IMT) at 10% of maximum inspiratory pressure. Training took place three times a week for 8 weeks and was fully supervised. Pre- and post-training measurements of lung function, maximum inspiratory pressure, maximum threshold pressure, exercise capacity, dyspnoea and QoL (Chronic Respiratory Disease Questionnaire; CRDQ) were obtained. H-IMT increased maximum inspiratory pressure by 29%, maximum threshold pressure by 56%, 6-min walk distance by 27 m, and improved dyspnoea and fatigue (CRDQ) by 1.4 and 0.9 points per item, respectively. These changes were significantly greater than any seen following S-IMT. In conclusion, high-intensity inspiratory muscle training improves inspiratory muscle function in subjects with moderate-to-severe chronic obstructive pulmonary disease, yielding meaningful reductions in dyspnoea and fatigue. PMID:16772388

  16. Acute effects of inspiratory muscle warm-up on pulmonary function in healthy subjects.

    PubMed

    Özdal, Mustafa

    2016-06-15

    The acute effects of inspiratory muscle warm-up on pulmonary functions were examined in 26 healthy male subjects using the pulmonary function test (PFT) in three different trials. The control trial (CON) did not involve inspiratory muscle warm-up, while the placebo (IMWp) and experimental (IMW) trials involved inspiratory muscle warm-up. There were no significant changes between the IMWp and CON trials (p>0.05). All the PFT measurements, including slow vital capacity, inspiratory vital capacity, forced vital capacity, forced expiratory volume in one second, maximal voluntary ventilation, and maximal inspiratory pressure were significantly increased by 3.55%, 12.52%, 5.00%, 2.75%, 2.66%, and 7.03% respectively, in the subjects in the IMW trial than those in the CON trial (p<0.05). These results show that inspiratory muscle warm-up improved the pulmonary functions. The mechanisms responsible for these improvements are probably associated with the concomitant increase in the inspiratory muscle strength, and the cooperation of the upper thorax, neck, and respiratory muscles, and increased level of reactive O2 species in muscle tissue, and potentially improvement of muscle O2 delivery-to-utilization. However, further investigation is required to determine the precise mechanisms responsible from among these candidates. PMID:26903486

  17. The influence of inspiratory muscle work history and specific inspiratory muscle training upon human limb muscle fatigue

    PubMed Central

    McConnell, Alison K; Lomax, Michelle

    2006-01-01

    The purpose of this study was to assess the influence of the work history of the inspiratory muscles upon the fatigue characteristics of the plantar flexors (PF). We hypothesized that under conditions where the inspiratory muscle metaboreflex has been elicited, PF fatigue would be hastened due to peripheral vasoconstriction. Eight volunteers undertook seven test conditions, two of which followed 4 week of inspiratory muscle training (IMT). The inspiratory metaboreflex was induced by inspiring against a calibrated flow resistor. We measured torque and EMG during isometric PF exercise at 85% of maximal voluntary contraction (MVC) torque. Supramaximal twitches were superimposed upon MVC efforts at 1 min intervals (MVCTI); twitch interpolation assessed the level of central activation. PF was terminated (Tlim) when MVCTI was <50% of baseline MVC. PF Tlim was significantly shorter than control (9.93 ± 1.95 min) in the presence of a leg cuff inflated to 140 mmHg (4.89 ± 1.78 min; P = 0.006), as well as when PF was preceded immediately by fatiguing inspiratory muscle work (6.28 ± 2.24 min; P = 0.009). Resting the inspiratory muscles for 30 min restored the PF Tlim to control. After 4 weeks, IMT, inspiratory muscle work at the same absolute intensity did not influence PF Tlim, but Tlim was significantly shorter at the same relative intensity. The data are the first to provide evidence that the inspiratory muscle metaboreflex accelerates the rate of calf fatigue during PF, and that IMT attenuates this effect. PMID:16973699

  18. Inspiratory muscle training to enhance recovery from mechanical ventilation: a randomised trial

    PubMed Central

    Bissett, Bernie M; Leditschke, I Anne; Neeman, Teresa; Boots, Robert; Paratz, Jennifer

    2016-01-01

    Background In patients who have been mechanically ventilated, inspiratory muscles remain weak and fatigable following ventilatory weaning, which may contribute to dyspnoea and limited functional recovery. Inspiratory muscle training may improve inspiratory muscle strength and endurance following weaning, potentially improving dyspnoea and quality of life in this patient group. Methods We conducted a randomised trial with assessor-blinding and intention-to-treat analysis. Following 48 hours of successful weaning, 70 participants (mechanically ventilated ≥7 days) were randomised to receive inspiratory muscle training once daily 5 days/week for 2 weeks in addition to usual care, or usual care (control). Primary endpoints were inspiratory muscle strength and fatigue resistance index (FRI) 2 weeks following enrolment. Secondary endpoints included dyspnoea, physical function and quality of life, post-intensive care length of stay and in-hospital mortality. Results 34 participants were randomly allocated to the training group and 36 to control. The training group demonstrated greater improvements in inspiratory strength (training: 17%, control: 6%, mean difference: 11%, p=0.02). There were no statistically significant differences in FRI (0.03 vs 0.02, p=0.81), physical function (0.25 vs 0.25, p=0.97) or dyspnoea (−0.5 vs 0.2, p=0.22). Improvement in quality of life was greater in the training group (14% vs 2%, mean difference 12%, p=0.03). In-hospital mortality was higher in the training group (4 vs 0, 12% vs 0%, p=0.051). Conclusions Inspiratory muscle training following successful weaning increases inspiratory muscle strength and quality of life, but we cannot confidently rule out an associated increased risk of in-hospital mortality. Trial registration number ACTRN12610001089022, results. PMID:27257003

  19. Preoperative Ambulatory Inspiratory Muscle Training in Patients Undergoing Esophagectomy. A Pilot Study

    PubMed Central

    Agrelli, Taciana Freitas; de Carvalho Ramos, Marisa; Guglielminetti, Rachel; Silva, Alex Augusto; Crema, Eduardo

    2012-01-01

    A major decline in pulmonary function is observed on the first day after upper abdominal surgery. This decline can reduce vital and inspiratory capacity and can culminate in restrictive lung diseases that cause atelectasis, reduced diaphragm movement, and respiratory insufficiency. The objective of this study was to evaluate the efficacy of preoperative ambulatory respiratory muscle training in patients undergoing esophagectomy. The sample consisted of 20 adult patients (14 men [70%] and 6 women [30%]) with a diagnosis of advanced chagasic megaesophagus. A significant increase in maximum inspiratory pressure was observed after inspiratory muscle training when compared with baseline values (from −55.059 ± 18.359 to −76.286 ± 16.786). Preoperative ambulatory inspiratory muscle training was effective in increasing respiratory muscle strength in patients undergoing esophagectomy and contributed to the prevention of postoperative complications. PMID:23113846

  20. Preoperative ambulatory inspiratory muscle training in patients undergoing esophagectomy. A pilot study.

    PubMed

    Agrelli, Taciana Freitas; de Carvalho Ramos, Marisa; Guglielminetti, Rachel; Silva, Alex Augusto; Crema, Eduardo

    2012-01-01

    A major decline in pulmonary function is observed on the first day after upper abdominal surgery. This decline can reduce vital and inspiratory capacity and can culminate in restrictive lung diseases that cause atelectasis, reduced diaphragm movement, and respiratory insufficiency. The objective of this study was to evaluate the efficacy of preoperative ambulatory respiratory muscle training in patients undergoing esophagectomy. The sample consisted of 20 adult patients (14 men [70%] and 6 women [30%]) with a diagnosis of advanced chagasic megaesophagus. A significant increase in maximum inspiratory pressure was observed after inspiratory muscle training when compared with baseline values (from -55.059 ± 18.359 to -76.286 ± 16.786). Preoperative ambulatory inspiratory muscle training was effective in increasing respiratory muscle strength in patients undergoing esophagectomy and contributed to the prevention of postoperative complications. PMID:23113846

  1. [Inspiratory muscle training in patients with chronic obstructive pulmonary disease].

    PubMed

    Lisboa, C; Borzone, G; Cruz, E

    1998-05-01

    We analyze the effect of inspiratory muscle training (IMT) in patients with chronic obstructive pulmonary disease (COPD), with special emphasis on its effects on inspiratory muscle function and clinical outcomes. We reviewed only randomized, controlled studies that have either controlled both the load and the breathing pattern when using resistive training or have employed a threshold trainer in which the load is independent of the pattern of breathing, since methodological aspects may explain inconsistent results in the literature. In these circumstances, most of the studies demonstrated positive effects on inspiratory muscle function. Clinical effects were seldom evaluated; limited available data showed a reduction in dyspnea that was related to an increase in maximal inspiratory pressures (PIMax). When exercise capacity was evaluated through the distance the patients were able to walk in 6 or 12 minutes, most studies demonstrated a significant increase. Other reported positive effects were improvement in nocturnal SaO2, inspiratory muscle power output and maximal inspiratory flow rate. Based in this review, a recommended training regime appears to be an intermediate load (30-40% PIMax) using a threshold device for 30 minutes daily for at least 5 weeks. Although in the literature the criteria for selecting patients are not always well defined, we consider IMT as a helpful procedure for pulmonar rehabilitation in those patients with a moderately severe inspiratory muscle dysfunction presenting dyspnea during daily living activities despite optimal therapy. PMID:9731440

  2. Relative activity of respiratory muscles during prescribed inspiratory muscle training in healthy people

    PubMed Central

    Jung, Ju-hyeon; Kim, Nan-soo

    2016-01-01

    [Purpose] This study aimed to determine the effects of different intensities of inspiratory muscle training on the relative respiratory muscle activity in healthy adults. [Subjects and Methods] Thirteen healthy male volunteers were instructed to perform inspiratory muscle training (0%, 40%, 60%, and 80% maximal inspiratory pressure) on the basis of their individual intensities. The inspiratory muscle training was performed in random order of intensities. Surface electromyography data were collected from the right-side diaphragm, external intercostal, and sternocleidomastoid, and pulmonary functions (forced expiratory volume in 1 s, forced vital capacity, and their ratio; peak expiratory flow; and maximal inspiratory pressure) were measured. [Results] Comparison of the relative activity of the diaphragm showed significant differences between the 60% and 80% maximal inspiratory pressure intensities and baseline during inspiratory muscle training. Furthermore, significant differences were found in sternocleidomastoid relative activity between the 60% and 80% maximal inspiratory pressure intensities and baseline during inspiratory muscle training. [Conclusion] During inspiratory muscle training in the clinic, the patients were assisted (verbally or through feedback) by therapists to avoid overactivation of their accessory muscles (sternocleidomastoid). This study recommends that inspiratory muscle training be performed at an accurate and appropriate intensity through the practice of proper deep breathing. PMID:27134409

  3. Effect of inspiratory muscle training with an intermediate load on inspiratory power output in COPD.

    PubMed

    Villafranca, C; Borzone, G; Leiva, A; Lisboa, C

    1998-01-01

    There is very little information about the effect of inspiratory muscle training on inspiratory flow (V'I) and thus on power output (PO) in patients with chronic obstructive pulmonary disease (COPD). In this study we aimed to evaluate the changes induced by training on the determinants of PO. Thirty one patients with severe COPD were randomly divided into: Group 1, trained with 30% maximal inspiratory pressure (PI,max); Group 2, with 10% PI,max; and Group 3 also trained with 30% PI,max, but the breathing pattern was evaluated while performing the training manoeuvres along inspiratory muscle training (IMT). All groups used a threshold device for 10 weeks. The PO for each of the loads during an incremental threshold test was evaluated prior to and after training. Maximal PO (POmax) increased in all groups, but the increment was higher in groups trained with 30% PI,max (p<0.005), mainly due to an increase in V'I. Group 3 showed a progressive increase in V'I (p<0.001) during the training manoeuvres in spite of an increase in load along IMT. In addition, the load after IMT was overcome with a shorter inspiratory time (tI) (p<0.02), a smaller tI/total duration of the respiratory cycle (t(tot)), (p<0.001) with no change in tidal volume or t(tot). The increment in POmax in this group correlated with the V'I generated while training (r=0.85; p<0.0001). We conclude that in patients with chronic obstructive pulmonary disease, the use of an intermediate threshold load for training improves power output mainly by increasing inspiratory flow, an effect consistent with an increase in shortening velocity of inspiratory muscles. PMID:9543266

  4. Inspiratory muscle training in adults with chronic obstructive pulmonary disease: an update of a systematic review.

    PubMed

    Geddes, E Lynne; O'Brien, Kelly; Reid, W Darlene; Brooks, Dina; Crowe, Jean

    2008-12-01

    The purpose was to update an original systematic review to determine the effect of inspiratory muscle training (IMT) on inspiratory muscle strength and endurance, exercise capacity, dyspnea and quality of life for adults with chronic obstructive pulmonary disease (COPD). The original MEDLINE and CINAHL search to August 2003 was updated to January 2007 and EMBASE was searched from inception to January 2007. Randomized controlled trials, published in English, with adults with stable COPD, comparing IMT to sham IMT or no intervention, low versus high intensity IMT, and different modes of IMT were included. Nineteen of 274 articles in the original search met the inclusion criteria. The updated search revealed 17 additional articles; 6 met the inclusion criteria, all of which compared targeted, threshold or normocapneic hyperventilation IMT to sham IMT. An update of the sub-group analysis comparing IMT versus sham IMT was performed with 10 studies from original review and 6 from the update. Sixteen meta-analyses are reported. Results demonstrated significant improvements in inspiratory muscle strength (PI(max), PI(max) % predicted, peak inspiratory flow rate), inspiratory muscle endurance (RMET, inspiratory threshold loading, MVV), exercise capacity (Ve(max), Borg Score for Respiratory Effort, 6MWT), Transitional Dyspnea Index (focal score, functional impairment, magnitude of task, magnitude of effort), and the Chronic Respiratory Disease Questionnaire (quality of life). Results suggest that targeted, threshold or normocapneic hyperventilation IMT significantly increases inspiratory muscle strength and endurance, improves outcomes of exercise capacity and one measure of quality of life, and decreases dyspnea for adults with stable COPD. PMID:18708282

  5. Prophylactic inspiratory muscle training in patients undergoing coronary artery bypass graft.

    PubMed

    Weiner, P; Zeidan, F; Zamir, D; Pelled, B; Waizman, J; Beckerman, M; Weiner, M

    1998-05-01

    Pulmonary complications after cardiac surgery are a leading cause of postoperative morbidity and mortality. Respiratory muscle weakness may contribute to the postoperative pulmonary abnormalities. We hypothesized that: (1) there is a decrease in inspiratory muscle strength (PImax at residual volume) and endurance (Pmpeak/PImax) following coronary artery bypass graft (CABG); (2) this weakness is associated with reduced pulmonary function tests (PFTs), impaired gas exchange, and a higher rate of pulmonary complications; and (3) prophylactic inspiratory muscle training (IMT) can prevent those changes. Eighty-four candidates for CABG, with ages ranging from 33 to 82 years, were evaluated prior to operation and randomized into two groups: 42 patients underwent IMT using a threshold trainer for 30 min/day for 2 weeks, 1 month before operation (group A); 42 patients served as a control group and underwent sham training (group B). There was a significant decrease in respiratory muscle function, PFTs, and gas exchange in the control group following CABG, whereas these parameters remained similar to those before entering the study in the training group. The differences between the groups were statistically significant. In addition 11 (26%) patients in the control group but only 2 (5%) in the training group needed postsurgical mechanical ventilation longer than 24 hours, CABGs have a significant deteriorating effect on inspiratory muscle function, PFTs, and arterial blood gases. The decrease in these parameters can be prevented by prophylactic inspiratory muscle training, which may also prevent postsurgical pulmonary complications. PMID:9564282

  6. Recruitment of some respiratory muscles during three maximal inspiratory manoeuvres.

    PubMed Central

    Nava, S; Ambrosino, N; Crotti, P; Fracchia, C; Rampulla, C

    1993-01-01

    BACKGROUND--A study was undertaken to determine the level of recruitment of the muscles used in the generation of respiratory muscle force, and to ascertain whether maximal diaphragmatic force and maximal inspiratory muscle force need to be measured by separate tests. The level of activity of three inspiratory muscles and one expiratory muscle during three maximal respiratory manoeuvres was studied: (1) maximal inspiration against a closed airway (Muller manoeuvre or maximal inspiratory pressure (MIP)); (2) maximal inspired manoeuvre followed by a maximal expiratory effort (combined manoeuvre); and (3) maximal inspiratory sniff through the nose (sniff manoeuvre). METHODS--All the manoeuvres were performed from functional residual capacity. The gastric (PGA) and oesophageal (POES) pressures and their difference, transdiaphragmatic pressure (PDI), and the integrated EMG activity of the diaphragm (EDI), the sternomastoid (ESTR), the intercostal parasternals (ERIC), and the rectus abdominis muscles (ERA) were recorded. RESULTS--Mean (SD) PDI values for the Muller, combined, and sniff manoeuvres were: 127.6 (19.4), 162.7 (22.2), and 136.6 (24.8) cm H2O, respectively. The pattern of rib cage muscle recruitment (POES/PDI) was similar for the Muller and sniff manoeuvres (88% and 80% respectively), and was 58% in the combined manoeuvre, confirming data previously reported in the literature. Peak EDI amplitude was greater during the sniff manoeuvre in all subjects (100%) than during the combined (88.1%) and Muller (61.1%) manoeuvres. ESTR and EIC were more active in the Muller and the sniff manoeuvres. The contribution of the expiratory muscle (ERA) to the three manoeuvres was 100% in the combined, 26.1% for the sniff, and 11.5% for the Muller manoeuvre. CONCLUSIONS--Each of these three manoeuvres results in different mechanisms of inspiratory and expiratory muscle activation and the intrathoracic and intra-abdominal pressures generated are a reflection of the interaction

  7. Activity of latissimus dorsi muscle during inspiratory threshold loads.

    PubMed

    Orozco-Levi, M; Gea, J; Monells, J; Aran, X; Aguar, M C; Broquetas, J M

    1995-03-01

    The ability of the latissimus dorsi muscle (LD) to participate as an accessory inspiratory muscle has been the subject of controversy. Electromyographic (EGM) activity of LD was evaluated in 11 healthy subjects (aged 30 +/- 2 yrs; forced expiratory volume in one second (FEV1) 106 +/- 5% predicted; maximal inspiratory pressure (Pmax), 120 +/- 6 cmH2O) under different breathing conditions. The ipsilateral biceps brachii was chosen as the control muscle. The EMG was recorded from surface electrodes, but needle electrodes were also used for LD evaluation in a subset of three subjects. The EMG signal from both muscles was recorded simultaneously, rectified and integrated, with subtraction of the electrocardiographic signal. Situations evaluated were: 1) maximal voluntary contraction (MVC); 2) apnoea; and 3) breathing under progressive inspiratory threshold loads (20-100% Pmax, at 20% intervals). A close relationship was evident between LD recordings from surface and needle electrodes (r = 0.975). Activity of LD at baseline was 1.8 +/- 0.4% MVC, and showed a phasic increase during inspiration under loads. This change had a linear tendency and was significant for loads corresponding to 40, 60, 80 and 100% of Pmax when compared to the control muscle. At this latter level, LD activity was equivalent to 32 +/- 5% MVC (range 11-61%), whereas mean activity of the control muscle was less than 7.5% MVC.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7789491

  8. Inspiratory muscle training in adults with chronic obstructive pulmonary disease: a systematic review.

    PubMed

    Geddes, E Lynne; Reid, W Darlene; Crowe, Jean; O'Brien, Kelly; Brooks, Dina

    2005-11-01

    The purpose of this study was to conduct a systematic review to determine the effect of inspiratory muscle training (IMT) on inspiratory muscle strength and endurance, exercise capacity, dyspnea and quality of life for adults with chronic obstructive pulmonary disease (COPD). A systematic review of the literature was conducted according the Cochrane Collaboration protocol using Medline and CINAHL. Nineteen of 274 extracted articles met the inclusion criteria and addressed comparisons of interest which included: IMT versus sham; IMT versus no intervention; low- versus high-intensity IMT; and two different modes of IMT. Thirteen meta-analyses were reported. Results indicate that targeted resistive or threshold IMT was associated with significant improvements in some outcomes of inspiratory muscle strength (PI(max) (cm H2O)) and endurance (Inspiratory Threshold Loading (kPa)), exercise capacity (Borg Scale for Respiratory Effort (modified Borg scale), Work Rate maximum (Watts)), and dyspnea (Transition Dyspnea Index), whereas IMT without a target or not using threshold training did not show improvement in these variables. There was no conclusive evidence regarding quality of life measures. IMT is effective for adults with COPD when using threshold or targeted devices that control or provide a target for training intensity. PMID:15894478

  9. Systematic Review of Inspiratory Muscle Training After Cerebrovascular Accident.

    PubMed

    Martín-Valero, Rocío; De La Casa Almeida, Maria; Casuso-Holgado, Maria Jesus; Heredia-Madrazo, Alfonso

    2015-11-01

    This systematic review examines levels of evidence and recommendation grades of various therapeutic interventions of inspiratory muscle training in people who have had a stroke. Benefits from different levels of force and resistance in respiratory muscles are shown in this population. This review was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) directives and was completed in November 2014. The search limits were studies published in English between 2004 and 2014. Relevant studies were searched for in MEDLINE, PEDro, OAIster, Scopus, PsycINFO, Web of Knowledge, CINAHL, SPORTDiscus, DOAJ, Cochrane, Embase, Academic Search Complete, Fuente Académica, and MedicLatina. Initially, 20 articles were identified. After analyzing all primary documents, 14 studies were excluded. Only 6 studies were relevant to this review. Three different types of interventions were found (maximum inspiratory training, controlled training, and nonintervention) in 3 different groups. One specific study compared 3 inspiratory muscle training groups with a group of breathing exercises (diaphragmatic exercises with pursed lips) and a control group. Future long-term studies with larger sample sizes are needed. It is necessary to apply respiratory muscle training as a service of the national health system and to consider its inclusion in the conventional neurological program. PMID:26493591

  10. Cycle ergometer and inspiratory muscle training in chronic obstructive pulmonary disease.

    PubMed

    Larson, J L; Covey, M K; Wirtz, S E; Berry, J K; Alex, C G; Langbein, W E; Edwards, L

    1999-08-01

    In patients with chronic obstructive pulmonary disease (COPD) the intensity of aerobic training is limited by dyspnea. Improving strength of the inspiratory muscles could enhance aerobic exercise training by reducing exercise-related dyspnea. We examined effects of home-based inspiratory muscle training (IMT) and cycle ergometry training (CET) in 53 patients with moderate to severe COPD (FEV(1)% pred, 50 +/- 17 [mean +/- SD]). Patients were randomly assigned to 4 mo of training in one of four groups: IMT, CET, CET + IMT, or health education (ED). Patients were encouraged to train to the limits of their dyspnea. Inspiratory muscle strength and endurance increased in IMT and CET + IMT groups compared with CET and ED groups (p < 0. 01). Peak oxygen uptake increased and heart rate, minute ventilation, dyspnea, and leg fatigue decreased at submaximal work rates in the CET and CET + IMT groups compared with the IMT and ED groups (p < 0. 01). There were no differences between the CET and CET + IMT groups. Home-based CET produced a physiological training effect and reduced exercise-related symptoms while IMT increased respiratory muscle strength and endurance. The combination of CET and IMT did not produce additional benefits in exercise performance and exercise-related symptoms. This is the first study to demonstrate a physiological training effect with home-based exercise training. PMID:10430720

  11. Inspiratory Muscle Training in Patients with Heart Failure: A Systematic Review

    PubMed Central

    Lin, Suh-Jen; McElfresh, Jessica; Hall, Benjamin; Bloom, Rachel; Farrell, Kellie

    2012-01-01

    Purpose The purpose of this review was to assess the quality of evidence on inspiratory muscle training (IMT) in patients with heart failure and to provide an overview on subject selection, training protocols, and outcome achieved with IMT. Methods Literature search was first performed via the PubMed database, and additional references were identified from the Scopus citation index. Articles of the review type and of clinical trials published in English were included. Quality of the articles was assessed using Sackett's levels of evidence and rigor of methodology was assessed using PEDro (Physiotherapy Evidence Database) criteria for randomized controlled trials and the Downs & Black tool for cohort studies. Results Twelve articles of clinical trials were included. Typical training protocols involved daily training with intensity greater than 30% of maximal inspiratory pressure (PImax), duration of 20 to 30 minutes (continuous or incremental) and using a pressure threshold muscle trainer. The effect sizes of PImax, walk test distance, and dyspnea were moderate to large across these studies. Effects on quality of life scores were inconsistent. Conclusion Inspiratory muscle training is beneficial for improving respiratory muscle strength, functional capacity, and dyspnea in patients with stable heart failure and respiratory muscle weakness. PMID:22993500

  12. Inspiratory muscle training for patients with chronic obstructive pulmonary disease: a practical guide for clinicians.

    PubMed

    Hill, Kylie; Cecins, Nola M; Eastwood, Peter R; Jenkins, Sue C

    2010-09-01

    Reduced inspiratory muscle strength is common in people with chronic obstructive pulmonary disease (COPD) and is associated with dyspnea and decreased exercise capacity. Most studies of inspiratory muscle training (IMT) in COPD have demonstrated increased inspiratory muscle strength. Many have also shown improvements in dyspnea and exercise capacity. However, a persisting challenge when translating and applying the findings of these studies in clinical practice is the disparity in training loads, modalities, and outcomes measures used in the different studies. This commentary summarizes our clinical and research experience with a threshold IMT device with the aim of providing clinicians interested in prescribing IMT in this population with practical recommendations regarding patient selection, assessment, and implementation of training. We propose using an interval-based high-intensity threshold IMT program for people who are unable to participate fully in whole-body exercise training because of comorbidities such as severe musculoskeletal problems. Initial training loads equivalent to at least 30% of a person's maximum inspiratory pressure (PImax) are required for all people undertaking IMT. Supervision, which includes monitoring of oxygen saturation throughout the first training session, is recommended, and patients are warned to expect transient delayed-onset muscle soreness, a consequence of muscle adaptation to an unaccustomed activity. We recommend training be undertaken 3 times a week for 8 weeks, with loads progressively increased as symptoms permit. It is prudent to exclude people at risk of pneumothorax or spontaneous rib fracture. Evaluation of IMT should include measures of PImax, dyspnea, health-related quality of life, and exercise capacity. PMID:20801269

  13. Tonic activity in inspiratory muscles during continuous negative airway pressure.

    PubMed

    Meessen, N E; van der Grinten, C P; Folgering, H T; Luijendijk, S C

    1993-05-01

    We studied tonic inspiratory activity (TIA) induced by continuous negative airway pressure (CNAP) in anaesthetized, spontaneously breathing cats. TIA in the diaphragm and parasternal intercostal muscles (ICM) was quantified in response to tracheal pressure (PTR) = -0.3 to -1.2 kPa. To differentiate between reflexes from rapidly adapting receptors (RARs), slowly adapting receptors (SARs) and C-fiber endings different temperatures of the vagus nerves (TVG) were used between 4 and 37 degrees C. At PTR = -1.2 kPa mean TIA values were 41% and 62% of peak inspiratory EMG activity of control breaths for the diaphragm and ICM, respectively. After vagotomy and for TVG < 6 degrees C CNAP did not induce TIA anymore. Changes in inspiratory and expiratory time during vagal cooling down to 4 degrees C confirmed the selective block of conductance in vagal afferents of the three types of lung receptors. We conclude that CNAP-induced TIA results from stimulation of RARs. Our data strongly indicate that stimulation of SARs suppresses TIA, whereas C-fiber endings are not involved in TIA at all. The results suggest that part of the hyperinflation in bronchial asthma may be caused by TIA in response to mechanical stimulation of RARs. PMID:8327788

  14. The effect of inspiratory muscle fatigue on breathing pattern and ventilatory response to CO2.

    PubMed Central

    Mador, M J; Tobin, M J

    1992-01-01

    1. The effects of inducing inspiratory muscle fatigue on the subsequent breathing pattern were examined during resting unstimulated breathing and during CO2 rebreathing. In addition, we examined whether induction of inspiratory muscle fatigue alters CO2 responsiveness. 2. Global inspiratory muscle fatigue and diaphragmatic fatigue were achieved by having subjects breathe against an inspiratory resistive load while generating a predetermined fraction of either their maximal mouth pressure or maximal transdiaphragmatic pressure until they were unable to generate the target pressure. 3. Induction of inspiratory muscle fatigue had no effect on the subsequent breathing pattern during either unstimulated breathing or during CO2 rebreathing. 4. Following induction of inspiratory muscle fatigue, the slope of the ventilatory response to CO2 was significantly decreased from 18.8 +/- 3.3 during control to 13.8 +/- 2.1 l min-1 (% end-tidal CO2 concentration)-1 with fatigue (P < 0.02). PMID:1484352

  15. Effect of inspiratory muscle work on peripheral fatigue of locomotor muscles in healthy humans

    PubMed Central

    Romer, Lee M; Lovering, Andrew T; Haverkamp, Hans C; Pegelow, David F; Dempsey, Jerome A

    2006-01-01

    The work of breathing required during maximal exercise compromises blood flow to limb locomotor muscles and reduces exercise performance. We asked if force output of the inspiratory muscles affected exercise-induced peripheral fatigue of locomotor muscles. Eight male cyclists exercised at ≥ 90% peak O2 uptake to exhaustion (CTRL). On a separate occasion, subjects exercised for the same duration and power output as CTRL (13.2 ± 0.9 min, 292 W), but force output of the inspiratory muscles was reduced (−56% versus CTRL) using a proportional assist ventilator (PAV). Subjects also exercised to exhaustion (7.9 ± 0.6 min, 292 W) while force output of the inspiratory muscles was increased (+80% versus CTRL) via inspiratory resistive loads (IRLs), and again for the same duration and power output with breathing unimpeded (IRL-CTRL). Quadriceps twitch force (Qtw), in response to supramaximal paired magnetic stimuli of the femoral nerve (1–100 Hz), was assessed pre- and at 2.5 through to 70 min postexercise. Immediately after CTRL exercise, Qtw was reduced −28 ± 5% below pre-exercise baseline and this reduction was attenuated following PAV exercise (−20 ± 5%; P < 0.05). Conversely, increasing the force output of the inspiratory muscles (IRL) exacerbated exercise-induced quadriceps muscle fatigue (Qtw=−12 ± 8% IRL-CTRL versus −20 ± 7% IRL; P < 0.05). Repeat studies between days showed that the effects of exercise per se, and of superimposed inspiratory muscle loading on quadriceps fatigue were highly reproducible. In conclusion, peripheral fatigue of locomotor muscles resulting from high-intensity sustained exercise is, in part, due to the accompanying high levels of respiratory muscle work. PMID:16373384

  16. Inspiratory muscle training reduces blood lactate concentration during volitional hyperpnoea.

    PubMed

    Brown, Peter I; Sharpe, Graham R; Johnson, Michael A

    2008-09-01

    Although reduced blood lactate concentrations ([lac(-)](B)) have been observed during whole-body exercise following inspiratory muscle training (IMT), it remains unknown whether the inspiratory muscles are the source of at least part of this reduction. To investigate this, we tested the hypothesis that IMT would attenuate the increase in [lac(-)](B) caused by mimicking, at rest, the breathing pattern observed during high-intensity exercise. Twenty-two physically active males were matched for 85% maximal exercise minute ventilation (.V(E) max) and divided equally into an IMT or a control group. Prior to and following a 6 week intervention, participants performed 10 min of volitional hyperpnoea at the breathing pattern commensurate with 85% .V(E) max. The IMT group performed 6 weeks of pressure-threshold IMT; the control group performed no IMT. Maximal inspiratory mouth pressure increased (mean +/- SD) 31 +/- 22% following IMT and was unchanged in the control group. Prior to the intervention in the control group, [lac(-)](B) increased from 0.76 +/- 0.24 mmol L(-1) at rest to 1.50 +/- 0.60 mmol L(-1) (P < 0.05) following 10 min volitional hyperpnoea. In the IMT group, [lac(-)](B) increased from 0.85 +/- 0.40 mmol L(-1) at rest to 2.02 +/- 0.85 mmol L(-1) following 10 min volitional hyperpnoea (P < 0.05). After 6 weeks, increases in [lac(-)](B) during volitional hyperpnoea were unchanged in the control group. Conversely, following IMT the increase in [lac(-)](B) during volitional hyperpnoea was reduced by 17 +/- 37% and 25 +/- 34% following 8 and 10 min, respectively (P < 0.05). In conclusion, increases in [lac(-)](B) during volitional hyperpnoea at 85% .V(E) max were attenuated following IMT. These findings suggest that the inspiratory muscles were the source of at least part of this reduction, and provide a possible explanation for some of the IMT-mediated reductions in [lac(-)](B), often observed during whole-body exercise. PMID:18560878

  17. The effect of progressive high-intensity inspiratory muscle training and fixed high-intensity inspiratory muscle training on the asymmetry of diaphragm thickness in stroke patients

    PubMed Central

    Jung, Ju-hyeon; Kim, Nan-soo

    2015-01-01

    [Purpose] This study investigated the effects of progressive load and fixed load high-intensity inspiratory muscle training on the asymmetry of diaphragm thickness in stroke patients. [Subjects] Twenty-one stroke patients were assigned to one of three groups: progressive load high-intensity inspiratory muscle training (n = 8), fixed load high-intensity inspiratory muscle training (n = 6), and controls (n = 7). [Methods] The progressive load and fixed load high-intensity inspiratory muscle training participants undertook an exercise program for 20 minutes, three times weekly, for 6 weeks. After each session, diaphragm thickness was measured using ultrasonography. The diaphragm asymmetry ratio and diaphragm thickening ratio were standardized using a formula. [Results] After intervention, the diaphragm asymmetry ratio significantly differed among the three groups, and the diaphragm asymmetry ratio significantly increased in the control group. A significant increase was identified in the diaphragm thickening ratio within the progressive load and fixed load high-intensity inspiratory muscle training groups. [Conclusion] Progressive load and fixed load high-intensity inspiratory muscle training decreased the asymmetry of diaphragm thickness in stroke patients; this effect, in turn, increased the diaphragm thickening ratio in stroke patients. The two interventions examined here should be selectively applied to individuals in the clinical field. PMID:26644689

  18. Effects of inspiratory muscle training on exercise responses in Paralympic athletes with cervical spinal cord injury.

    PubMed

    West, C R; Taylor, B J; Campbell, I G; Romer, L M

    2014-10-01

    We asked whether specific inspiratory muscle training (IMT) improves respiratory structure and function and peak exercise responses in highly trained athletes with cervical spinal cord injury (SCI). Ten Paralympic wheelchair rugby players with motor-complete SCI (C5-C7) were paired by functional classification then randomly assigned to an IMT or placebo group. Diaphragm thickness (B-mode ultrasonography), respiratory function [spirometry and maximum static inspiratory (PI ,max ) and expiratory (PE ,max ) pressures], chronic activity-related dyspnea (Baseline and Transition Dyspnea Indices), and physiological responses to incremental arm-crank exercise were assessed before and after 6 weeks of pressure threshold IMT or sham bronchodilator treatment. Compared to placebo, the IMT group showed significant increases in diaphragm thickness (P = 0.001) and PI ,max (P = 0.016). There was a significant increase in tidal volume at peak exercise in IMT vs placebo (P = 0.048) and a strong trend toward an increase in peak work rate (P = 0.081, partial eta-squared = 0.33) and peak oxygen uptake (P = 0.077, partial eta-squared = 0.34). No other indices changed post-intervention. In conclusion, IMT resulted in significant diaphragmatic hypertrophy and increased inspiratory muscle strength in highly trained athletes with cervical SCI. The strong trend, with large observed effect, toward an increase in peak aerobic performance suggests IMT may provide a useful adjunct to training in this population. PMID:23530708

  19. Inspiratory muscle training improves 100 and 200 m swimming performance.

    PubMed

    Kilding, Andrew E; Brown, Sarah; McConnell, Alison K

    2010-02-01

    Inspiratory muscle training (IMT) has been shown to improve time trial performance in competitive athletes across a range of sports. Surprisingly, however, the effect of specific IMT on surface swimming performance remains un-investigated. Similarly, it is not known whether any ergogenic influence of IMT upon swimming performance is confined to specific race distances. To determine the influence of IMT upon swimming performance over 3 competitive distances, 16 competitive club-level swimmers were assigned at random to either an experimental (pressure threshold IMT) or sham IMT placebo control group. Participants performed a series of physiological and performance tests, before and following 6 weeks of IMT, including (1) an incremental swim test to the limit of tolerance to determine lactate, heart rate and perceived exertion responses; (2) standard measures of lung function (forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow) and maximal inspiratory pressure (MIP); and (3) 100, 200 and 400 m swim time trials. Training utilised a hand-held pressure threshold device and consisted of 30 repetitions, twice per day. Relative to control, the IMT group showed the following percentage changes in swim times: 100 m, -1.70% (90% confidence limits, +/-1.4%), 200 m, -1.5% (+/-1.0), and 400 m, 0.6% (+/-1.2). Large effects were observed for MIP and rates of perceived exertion. In conclusion, 6 weeks of IMT has a small positive effect on swimming performance in club-level trained swimmers in events shorter than 400 m. PMID:19841931

  20. Respiratory Muscle Activity During Simultaneous Stationary Cycling and Inspiratory Muscle Training.

    PubMed

    Hellyer, Nathan J; Folsom, Ian A; Gaz, Dan V; Kakuk, Alynn C; Mack, Jessica L; Ver Mulm, Jacyln A

    2015-12-01

    Inspiratory muscle training (IMT) strengthens the muscles of respiration, improves breathing efficiency, and increases fitness. The IMT is generally performed independently of aerobic exercise; however, it is not clear whether there is added benefit of performing the IMT while simultaneously performing aerobic exercise in terms of activating and strengthening inspiratory muscles. The purpose of our study was to determine the effect of IMT on respiratory muscle electromyography (EMG) activity during stationary cycling in the upright and drops postures as compared with that when the IMT was performed alone. Diaphragm and sternocleidomastoid EMG activity was measured under different resting and cycling postures, with and without the use of the IMT at 40% maximal inspiratory pressure (n = 10; mean age 37). Cycling in an upright posture while simultaneously performing the IMT resulted in a significantly greater diaphragm EMG activity than while performing the IMT at rest in upright or drops postures (p ≤ 0.05). Cycling in drops postures while performing the IMT had a significantly greater diaphragm EMG activity than when performing the IMT at rest in either upright or drops postures (p ≤ 0.05). Sternocleidomastoid muscle activity increased with both cycling and IMT, although posture had little effect. These results support our hypothesis in that the IMT while cycling increases respiratory EMG activity to a significantly greater extent than when performing the IMT solely at rest, suggesting that the combination of IMT and cycling may provide an additive training effect. PMID:26584054

  1. The Role of Inspiratory Muscle Training in Sickle Cell Anemia Related Pulmonary Damage due to Recurrent Acute Chest Syndrome Attacks

    PubMed Central

    Camcıoğlu, Burcu; Boşnak-Güçlü, Meral; Karadallı, Müşerrefe Nur; Akı, Şahika Zeynep; Türköz-Sucak, Gülsan

    2015-01-01

    Background. The sickling of red blood cells causes a constellation of musculoskeletal, cardiovascular, and pulmonary manifestations. A 32-year-old gentleman with sickle cell anemia (SCA) had been suffering from recurrent acute chest syndrome (ACS). Aim. To examine the effects of inspiratory muscle training (IMT) on pulmonary functions, respiratory and peripheral muscle strength, functional exercise capacity, and quality of life in this patient with SCA. Methods. Functional exercise capacity was evaluated using six-minute walk test, respiratory muscle strength using mouth pressure device, hand grip strength using hand-held dynamometer, pain using Visual Analogue Scale, fatigue using Fatigue Severity Scale, dyspnea using Modified Medical Research Council Scale, and health related quality of life using European Organization for Research and Treatment of Cancer QOL measurement. Results. A significant improvement has been demonstrated in respiratory muscle strength, functional exercise capacity, pain, fatigue, dyspnea, and quality of life. There was no admission to emergency department due to acute chest syndrome in the following 12 months after commencing regular erythrocytapheresis. Conclusion. This is the first report demonstrating the beneficial effects of inspiratory muscle training on functional exercise capacity, respiratory muscle strength, pain, fatigue, dyspnea, and quality of life in a patient with recurrent ACS. PMID:26060589

  2. The Role of Inspiratory Muscle Training in Sickle Cell Anemia Related Pulmonary Damage due to Recurrent Acute Chest Syndrome Attacks.

    PubMed

    Camcıoğlu, Burcu; Boşnak-Güçlü, Meral; Karadallı, Müşerrefe Nur; Akı, Şahika Zeynep; Türköz-Sucak, Gülsan

    2015-01-01

    Background. The sickling of red blood cells causes a constellation of musculoskeletal, cardiovascular, and pulmonary manifestations. A 32-year-old gentleman with sickle cell anemia (SCA) had been suffering from recurrent acute chest syndrome (ACS). Aim. To examine the effects of inspiratory muscle training (IMT) on pulmonary functions, respiratory and peripheral muscle strength, functional exercise capacity, and quality of life in this patient with SCA. Methods. Functional exercise capacity was evaluated using six-minute walk test, respiratory muscle strength using mouth pressure device, hand grip strength using hand-held dynamometer, pain using Visual Analogue Scale, fatigue using Fatigue Severity Scale, dyspnea using Modified Medical Research Council Scale, and health related quality of life using European Organization for Research and Treatment of Cancer QOL measurement. Results. A significant improvement has been demonstrated in respiratory muscle strength, functional exercise capacity, pain, fatigue, dyspnea, and quality of life. There was no admission to emergency department due to acute chest syndrome in the following 12 months after commencing regular erythrocytapheresis. Conclusion. This is the first report demonstrating the beneficial effects of inspiratory muscle training on functional exercise capacity, respiratory muscle strength, pain, fatigue, dyspnea, and quality of life in a patient with recurrent ACS. PMID:26060589

  3. Inspiratory muscle training with threshold or incentive spirometry: Which is the most effective?

    PubMed

    Paiva, Dulciane Nunes; Assmann, Laíse Bender; Bordin, Diogo Fanfa; Gass, Ricardo; Jost, Renan Trevisan; Bernardo-Filho, Mario; França, Rodrigo Alves; Cardoso, Dannuey Machado

    2015-01-01

    Inspiratory muscular training (IMT) increases the respiratory muscle strength, however, there is no data demonstrating its superiority over the incentive spirometry (IS) in doing so. Values of muscle strength after IMT (Threshold IMT(®)) and by the IS (Voldyne(®)) in healthy females was compared. Subjects (n=40) were randomly divided into control group (CG, n=14), IS group (ISG, n=13) and threshold group (TG, n=13). PImax was measured before (pre-IMT), at 15 and 30 days of IMT. There was an increase in PImax of the TG at 15 days (p<0.001) and 30 days of IMT (p<0.001). The same occurred with the ISG, which increased the PImax at 15 days (p<0.001) and 30 days of training (p<0.001). After 30 days of IMT, the TG presented a PImax which was significantly higher than ISG and the CG (p=0.045 and p<0.001, respectively). It can be concluded that IMT by threshold was more effective in increasing muscle strength than the Voldyne. PMID:25926370

  4. Assessment of respiratory muscle function and strength.

    PubMed Central

    Syabbalo, N.

    1998-01-01

    Measurement of respiratory muscle strength is useful in order to detect respiratory muscle weakness and to quantify its severity. In patients with severe respiratory muscle weakness, vital capacity is reduced but is a non-specific and relatively insensitive measure. Conventionally, inspiratory and expiratory muscle strength has been assessed by maximal inspiratory and expiratory mouth pressures sustained for 1 s (PImax and PEmax) during maximal static manoeuvre against a closed shutter. However, PImax and PEmax are volitional tests, and are poorly reproducible with an average coefficient of variation of 25%. The sniff manoeuvre is natural and probably easier to perform. Sniff pressure, and sniff transdiaphragmatic pressure are more reproducible and useful measure of diaphragmatic strength. Nevertheless, the sniff manoeuvre is also volition-dependent, and submaximal efforts are most likely to occur in patients who are ill or breathless. Non-volitional tests include measurements of twitch oesophageal, gastric and transdiaphragmatic pressure during bilateral electrical and magnetic phrenic nerve stimulation. Electrical phrenic nerve stimulation is technically difficult and is also uncomfortable and painful. Magnetic phrenic nerve stimulation is less painful and transdiaphragmatic pressure is reproducible in normal subjects. It is a relatively easy test that has the potential to become a widely adopted method for the assessment of diaphragm strength. The development of a technique to measure diaphragmatic sound (phonomyogram) during magnetic phrenic nerve stimulation opens the way for noninvasive assessment of diaphragmatic function. PMID:9683973

  5. Effects of a 10-Week Inspiratory Muscle Training Program on Lower-Extremity Mobility in People with Multiple Sclerosis

    PubMed Central

    Fry, Donna

    2011-01-01

    Pulmonary muscle weakness is common in ambulatory people with multiple sclerosis (MS) and may lead to deficits in mobility function. The purpose of this study was to examine the effect of a 10-week home-based exercise program using an inspiratory muscle threshold trainer (IMT) on the results of four lower-extremity physical performance tests in people with MS. The study design was a two-group (experimental-control), pretest-posttest study. Outcome measures consisted of pulmonary function measures including maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and maximal voluntary ventilation (MVV), and the following lower-extremity physical performance measures: the 6-Minute Walk (6MW) distance, gait velocity (GV), the Sit-to-Stand Test (SST), the Functional Stair Test (FST), and a balance test (BAL). A total of 46 ambulatory participants (Expanded Disability Status Scale [EDSS] score, 2.0–6.5) with MS were randomly assigned to an intervention group (mean EDSS score, 4.1) that received 10 weeks of home-based inspiratory muscle training or a nontreatment control group (mean EDSS score, 3.2). Of the original 46 participants, 20 intervention group participants and 19 control group participants completed the study. Compared with the control group, the intervention group made significantly greater gains in inspiratory muscle strength (P = .003) and timed balance scores (P = .008). A nonsignificant improvement in 6MW distance (P = .086) was also noted in the IMT-trained group as compared with the control group. This is the first study directly linking improvement in respiratory function to improvement in physical performance function in people with mild-to-moderate disability due to MS. PMID:24453703

  6. Comparison of incremental and constant load tests of inspiratory muscle endurance in COPD.

    PubMed

    Hill, K; Jenkins, S C; Philippe, D L; Shepherd, K L; Hillman, D R; Eastwood, P R

    2007-09-01

    The aim of the present study was to determine the relative value of incremental and constant load tests in detecting changes in inspiratory muscle endurance following high-intensity inspiratory muscle training (H-IMT) in chronic obstructive pulmonary disease. In total, 16 subjects (11 males; forced expiratory volume in one second (FEV(1)) 37.4+/-12.5%) underwent H-IMT. In addition, 17 subjects (11 males; FEV(1) 36.5+/-11.5%) underwent sham inspiratory muscle training (S-IMT). Training took place three times a week for 8 weeks. Baseline and post-training measurements were obtained of maximum threshold pressure sustained during an incremental load test (P(th,max)) and time breathing against a constant load (t(lim)). Breathing pattern was unconstrained. H-IMT increased P(th,max) and t(lim) relative to baseline and to any change seen following S-IMT. The effect size for P(th,max) was greater than for t(lim). Post-training tests were accompanied by changes in breathing pattern, including decreased duty cycle, which may have served to decrease inspiratory work and thereby contribute to the increase in P(th,max) and t(lim) in both groups. When assessing inspiratory muscle function in chronic obstructive pulmonary disease via tests in which the pattern of breathing is unconstrained, the current authors recommend incremental load tests be used in preference to constant load tests. However, to attribute changes in these tests to improvements in inspiratory muscle endurance, breathing pattern should be controlled. PMID:17504795

  7. Forced respiration during the deeper water immersion causes the greater inspiratory muscle fatigue in healthy young men

    PubMed Central

    Yamashina, Yoshihiro; Yokoyama, Hisayo; Naghavi, Nooshin; Hirasawa, Yoshikazu; Takeda, Ryosuke; Ota, Akemi; Imai, Daiki; Miyagawa, Toshiaki; Okazaki, Kazunobu

    2016-01-01

    [Purpose] The purpose of the present study was to evaluate the effect of water immersion at different water depths on respiratory function and the effect of inspiratory load breathing (ILB) during water immersion at different water depths on respiratory muscle strength evaluated by maximum inspiratory and expiratory pressures (PImax and PEmax, respectively). [Subjects] Eight healthy men participated randomly in three trials. [Methods] All sessions were conducted with the participants in a sitting position immersed in a water bath. We evaluated respiratory function, PImax and PEmax during submersion at three different levels of water depth (umbilicus; 4th-rib; or clavicle, CL) and after subsequent 15-min ILB. [Results] Decreases in vital capacity and expiratory reserve volume from baseline by water immersion were significantly greater in the CL trial than those in the other trials. In the CL trial, PImax was immediately reduced after ILB compared to that at baseline, and the reduction was significantly greater than those in the other trials. PEmax was not affected by ILB in any of the trials. [Conclusion] Forced respiration during deeper water immersion caused greater inspiratory muscle fatigue in healthy young men. PMID:27064401

  8. Forced respiration during the deeper water immersion causes the greater inspiratory muscle fatigue in healthy young men.

    PubMed

    Yamashina, Yoshihiro; Yokoyama, Hisayo; Naghavi, Nooshin; Hirasawa, Yoshikazu; Takeda, Ryosuke; Ota, Akemi; Imai, Daiki; Miyagawa, Toshiaki; Okazaki, Kazunobu

    2016-01-01

    [Purpose] The purpose of the present study was to evaluate the effect of water immersion at different water depths on respiratory function and the effect of inspiratory load breathing (ILB) during water immersion at different water depths on respiratory muscle strength evaluated by maximum inspiratory and expiratory pressures (PImax and PEmax, respectively). [Subjects] Eight healthy men participated randomly in three trials. [Methods] All sessions were conducted with the participants in a sitting position immersed in a water bath. We evaluated respiratory function, PImax and PEmax during submersion at three different levels of water depth (umbilicus; 4th-rib; or clavicle, CL) and after subsequent 15-min ILB. [Results] Decreases in vital capacity and expiratory reserve volume from baseline by water immersion were significantly greater in the CL trial than those in the other trials. In the CL trial, PImax was immediately reduced after ILB compared to that at baseline, and the reduction was significantly greater than those in the other trials. PEmax was not affected by ILB in any of the trials. [Conclusion] Forced respiration during deeper water immersion caused greater inspiratory muscle fatigue in healthy young men. PMID:27064401

  9. 'Functional' inspiratory and core muscle training enhances running performance and economy.

    PubMed

    Tong, Tomas K; McConnell, Alison K; Lin, Hua; Nie, Jinlei; Zhang, Haifeng; Wang, Jiayuan

    2014-08-26

    We compared the effects of two 6-week high-intensity interval training interventions. Under the control condition (CON), only interval training was undertaken, whilst under the intervention condition (ICT), interval training sessions were followed immediately by core training, which was combined with simultaneous inspiratory muscle training - 'functional' IMT. Sixteen recreational runners were allocated to either ICT or CON groups. Prior to the intervention phase, both groups undertook a 4-week programme of 'foundation' IMT to control for the known ergogenic effect of IMT [30 inspiratory efforts at 50% maximal static inspiratory pressure (P0) per set, 2 sets.d, 6 d.wk]. The subsequent 6-week interval running training phase, consisted of 3-4 sessions.wk. In addition, the ICT group undertook four inspiratory-loaded core exercises [10 repetitions.set, 2 sets.d, inspiratory load set at 50% post-IMT P0] immediately after each interval training session. The CON group received neither core training nor functional IMT. Following the intervention phase, global inspiratory and core muscle functions increased in both groups (P<0.05), as evidenced by P0 and a sport-specific endurance plank test performance (SEPT), respectively. Compared to CON, the ICT group showed larger improvements in SEPT, running economy at the speed of the OBLA, and 1-hr running performance (3.04% vs 1.57%, P<0.05). The changes in these variables were inter-individually correlated (r≥0.57, n=16, P<0.05). Such findings suggest that the addition of inspiratory-loaded core conditioning into a high-intensity interval training program augments the influence of the interval program upon endurance running performance, and that this may be underpinned by an improvement in running economy. PMID:25162653

  10. Training the inspiratory muscles improves running performance when carrying a 25 kg thoracic load in a backpack.

    PubMed

    Faghy, Mark A; Brown, Peter I

    2016-08-01

    Load carriage (LC) exercise in physically demanding occupations is typically characterised by periods of low-intensity steady-state exercise and short duration, high-intensity exercise while carrying an external mass in a backpack; this form of exercise is also known as LC exercise. This induces inspiratory muscle fatigue and reduces whole-body performance. Accordingly we investigated the effect of inspiratory muscle training (IMT, 50% maximal inspiratory muscle pressure (PImax) twice daily for six week) upon running time-trial performance with thoracic LC. Nineteen healthy males formed a pressure threshold IMT (n = 10) or placebo control group (PLA; n = 9) and performed 60 min LC exercise (6.5 km h(-1)) followed by a 2.4 km running time trial (LCTT) either side of a double-blind six week intervention. Prior to the intervention, PImax was reduced relative to baseline, post-LC and post-LCTT in both groups (pooled data: 13 ± 7% and 16 ± 8%, respectively, p < .05) and similar changes were observed post-PLA. Post-IMT only, resting PImax increased +31% (p < .05) and relative to pre-IMT was greater post-LC (+19%) and post-LCTT (+18%, p < .05), however, the relative reduction in PImax at each time point was unchanged (13 ± 11% and 17 ± 9%, respectively, p > .05). In IMT only, heart rate and perceptual responses were reduced post-LC (p < .05). Time-trial performance was unchanged post-PLA and improved 8 ± 4% after IMT (p < .05). In summary, when wearing a 25 kg backpack, IMT attenuated the cardiovascular and perceptual responses to steady-state exercise and improved high-intensity time-trial performance which we attribute in part to reduced relative work intensity of the inspiratory muscles due to improved inspiratory muscle strength. These findings have real-world implications for occupational contexts. PMID:26274785

  11. Impact of a Behavioral-Based Intervention on Inspiratory Muscle Training Prescription by a Multidisciplinary Team

    ERIC Educational Resources Information Center

    Simms, Alanna M.; Li, Linda C.; Geddes, E. Lynne; Brooks, Dina; Hoens, Alison M.; Reid, W. Darlene

    2012-01-01

    Introduction: Our goal was to compare behavioral- and information-based interventions aimed at increasing prescription of inspiratory muscle training (IMT) for people with chronic obstructive pulmonary disease (COPD) by interdisciplinary teams during pulmonary rehabilitation (PR). Methods: Six hospital PR programs were randomly assigned to a…

  12. [Measurement of the reserve function of inspiratory muscle and its clinical significance].

    PubMed

    Xiao, X; Luo, Y; Chen, W; Yuan, Y; He, T; Zeng, J

    1995-06-01

    The principles of measuring inspiratory muscle tension-time index (TTim) and the ratio of the works of inspiration over the maximal works of inspiration (Wi/Wi(max)) were investigated and their formulae were deduced, i.e. TTim = (Pi x Ti)/(MIP x Ttot) and Wi/Wi(max) = (Pi x VT)/(MIP x IC). The importance of the inspiratory pressure and the maximal inspiratory pressure (MIP) measured at function residual capacity (FRC) level was emphasized. Both TTim and Wi/Wi(max) were measured in 35 normal subjects and 89 patients with chronic obstructive pulmonary disease (COPD). The results showed that normal value of TTim was 0.0253 +/- 0.0055 which corresponds to the normal value of the diaphragm tension-time index (TTdi = 0.02-0.03) reported by Bellemare. Patients with COPD had a mean TTim much higher than that of normals (P < 0.01). The works of inspiration (Wi) in patients with COPD increased, while the maximal works of inspiration (Wi(max)) declined, so Wi/Wi(max) became significantly greater than that of normals (P < 0.01). The results also showed that there was a linear relationship between Pi/Pimax and TTim or Wi/Wimax (r = 0.7891, 0.9738, 0.6459, 0.9327, P < 0.01). Therefore, we suggest that both TTim and Wi/Wimax can be used as clinical indices to reflect the reserve function of inspiratory muscles. PMID:7490035

  13. Target-flow inspiratory muscle training: breathing patterns and metabolic costs.

    PubMed

    Dekhuijzen, P N; Hopman, M T; Binkhorst, R A; Folgering, H T

    1991-01-01

    In target-flow inspiratory muscle training (TF-IMT), the generated inspiratory mouth pressure and the duration of the inspiration and expiration are standardized to given an adequate training stimulus to the inspiratory muscles. The acute effects of TF-IMT on the efficiency of breathing were studied in a group of 12 COPD patients with a ventilatory limitation of their exercise capacity (mean age 58, mean FEV1 46.2% of predicted) and in 15 normal subjects (mean age 30). Also, the effect of a 10 week period of TF-IMT on the maximal inspiratory mouth pressure (PImax) in the COPD patients was measured. After an unloaded baseline period, the subjects started to inspire through a target-flow device during 15 min, followed by a recovery phase of 5 min. During TF-IMT minute ventilation (VE) decreased only in the COPD group. The ventilatory equivalent for O2 (VE/VO2) and the dead space to tidal volume ratio (VD/VT) decreased in both groups. During recovery, VE, VE/VO2 and VD/VT remained below baseline values in the COPD group, but not in the control group. PCO2 and lactate concentrations did not change during TF-IMT. After the 10 week training period, PImax [means) (SD] increased from 5.7(2.2) to 8.2(2.7) kPa (p less than 0.05). The results indicate that with standardized TF-IMT, the inspiratory muscles can be trained effectively in COPD patients with a ventilatory limitation. The persistence of the decrease in VE, VE/VO2 and VD/VT after a training session may be an additional beneficial effect of TF-IMT. PMID:1783476

  14. Effects of inspiratory muscle training on exercise capacity and spontaneous physical activity in elderly subjects: a randomized controlled pilot trial.

    PubMed

    Aznar-Lain, S; Webster, A L; Cañete, S; San Juan, A F; López Mojares, L M; Pérez, M; Lucia, A; Chicharro, J L

    2007-12-01

    Inspiratory muscle training (IMT) has been shown to improve exercise capacity in diseased populations. We chose to examine the effects of eight weeks of IMT on exercise capacity and spontaneous physical activity in elderly individuals. Eighteen moderately active elderly subjects (68.1 +/- 6.8 years [mean +/- SD]; range 58 - 78 years) were randomly assigned to either an experimental group (n = 9) or a control group (n = 9) in a double-blind manner. All subjects underwent inspiratory muscle testing, treadmill exercise testing and a four-day measurement period of spontaneous physical activity (using accelerometry) both pre- and post-intervention. The experimental group underwent eight weeks of incremental IMT using a pressure threshold device, while the control group underwent sham training using identical devices. After IMT training, inspiratory muscle strength (mean + 21.5 cm H (2)O; 95 % CI: 9.3, 33.7; p = 0.002), V.O (2peak) (+ 2.8 ml x min (-1) x kg (-1); 95 % CI: 0.5, 5.2; p = 0.022), time to exhaustion during a fixed workload treadmill test (+ 7.1 min; 95 % CI: 1.8, 2.4; p = 0.013) and time engaged in moderate-to-vigorous physical activity (+ 59 min; 95 % CI: 15, 78; p = 0.008) improved. Except for a decline in moderate-to-vigorous physical activity, no significant changes were seen in the control group. Therefore, IMT may be a useful technique for positively influencing exercise capacity and physical activity in elderly individuals. PMID:17534784

  15. Effects of Exercise Training and Inspiratory Muscle Training in Spinal Cord Injury: A Systematic Review

    PubMed Central

    Sheel, A. William; Reid, Wendy Darlene; Townson, Andrea F; Ayas, Najib T; Konnyu, Kristin J

    2008-01-01

    Objective: To provide a systematic review of the studies assessing exercise training and inspiratory muscle training (IMT) in individuals for the improved respiratory function of patients with spinal cord injury (SCI). Methods: Thirteen studies (5 exercise training, 8 IMT) were identified. Articles were scored for their methodological quality using the Physiotherapy Evidence Database scores and Downs and Black tools for randomized and nonrandomized studies, respectively. Conclusions were based on the most rigorously executed studies using Sackett's levels of evidence. Results: Study comparison was compromised by diverse research designs; small sample sizes; and heterogeneity of studied populations, protocols, and outcome measures. Based on current literature, there is level 2 evidence supporting exercise training as an intervention to improve respiratory strength and endurance and level 4 evidence to support exercise training as an intervention that might improve resting and exercising respiratory function in people with SCI. There is level 4 evidence to support IMT as an intervention that might decrease dyspnea and improve respiratory function in people with SCI. Conclusions: There are insufficient data to strongly support the use of exercise training or IMT for improved respiratory function in people with SCI. There is some evidence of efficacy of both regimens; however, the evidence is not of the best possible quality. PMID:19086707

  16. Inspiratory muscle performance in endurance-trained elderly males during incremental exercise.

    PubMed

    Chlif, Mehdi; Keochkerian, David; Temfemo, Abdou; Choquet, Dominique; Ahmaidi, Said

    2016-07-01

    The aim of this study was to compare the inspiratory muscle performance during an incremental exercise of twelve fit old endurance-trained athletes (OT) with that of fit young athletes (YT) and healthy age-matched controls (OC). The tension-time index (TT0.1) was determined according to the equation TT0.1=P0.1/PImax×ti/ttot, where P0.1 is the mouth occlusion pressure, PImax the maximal inspiratory pressure and ti/ttot the duty cycle. For a given VCO2, OT group displayed P0.1, P0.1/PImax ratio, TT0.1 and effective impedance of the respiratory muscle values which were lower than OC group and higher than YT group. At maximal exercise, P0.1/PImax ratio and TT0.1 was still lower in the OT group than OC group and higher than YT group. This study showed lower inspiratory muscle performance attested by a higher (TT0.1) during exercise in the OT group than YT group, but appeared to be less marked in elderly men having performed lifelong endurance training compared with sedentary elderly subjects. PMID:26994757

  17. Maximal inspiratory mouth pressure in Japanese elite male athletes.

    PubMed

    Ohya, Toshiyuki; Hagiwara, Masahiro; Chino, Kentaro; Suzuki, Yasuhiro

    2016-08-01

    Maximal inspiratory mouth pressure (MIP) is a common measurement of inspiratory muscle strength, which is often used in a variety of exercises to evaluate the effects of inspiratory muscle training. An understanding of elite athletes' MIP characteristics is needed to guide sport-specific inspiratory muscle training programs. The purpose of this study was to investigate and better understand the MIP characteristics of elite athletes from a variety of sports. A total of 301 Japanese elite male athletes participated in this study. MIP was assessed using a portable autospirometer with a handheld mouth pressure meter. Athletes with higher body mass tended to have stronger MIP values, in absolute terms. In relative terms, however, athletes who regularly experienced exercise-induced inspiratory muscle fatigue tended to have stronger MIP values. Our findings suggest that athletes could benefit from prescribed, sport-specific, inspiratory muscle training or warm-ups. PMID:27181330

  18. Inspiratory muscle training during pulmonary rehabilitation in chronic obstructive pulmonary disease: A randomized trial.

    PubMed

    Beaumont, M; Mialon, P; Le Ber-Moy, C; Lochon, C; Péran, L; Pichon, R; Gut-Gobert, C; Leroyer, C; Morelot-Panzini, C; Couturaud, F

    2015-11-01

    Although recommended by international guidelines, the benefit of inspiratory muscle training (IMT) in addition to rehabilitation remains uncertain. The objective was to demonstrate the effectiveness of IMT on dyspnea using Borg scale and multidimensional dyspnea profile questionnaire at the end of a 6-minute walk test (6MWT) in patients with chronic obstructive pulmonary disease (COPD) with preserved average maximum inspiratory pressure (PImax) of 85 cm H2O (95% of predicted (pred.) value) and admitted for a rehabilitation program in a dedicated center. In a randomized trial, comparing IMT versus no IMT in 32 COPD patients without inspiratory muscle weakness (PImax >60 cm H2O) who were admitted for pulmonary rehabilitation (PR) for 3 weeks, we evaluated the effect of IMT on dyspnea, using both Borg scale and multidimensional dyspnea profile (MDP) at the end of the 6MWT, and on functional parameters included inspiratory muscle function (PImax) and 6MWT. All testings were performed at the start and the end of PR. In unadjusted analysis, IMT was not found to be associated with an improvement of either dyspnea or PImax. After adjustment on confounders (initial Borg score) and variables of interaction (forced expiratory volume in 1 second (FEV1)), we found a trend toward an improvement of "dyspnea sensory intensity", items from MDP and a significant improvement on the variation in the 2 items of MDP ("tight or constricted" and "breathing a lot"). In the subgroup of patients with FEV1 < 50% pred., 5 items of MDP were significantly improved, whereas no benefit was observed in patients with FEV1 > 50% pred. IMT did not significantly improve dyspnea or functional parameter in COPD patients with PImax > 60 cm H2O. However, in the subgroup of patients with FEV1 < 50% pred., MDP was significantly improved. PMID:26170421

  19. Inspiratory muscle training in chronic airflow limitation: comparison of two different training loads with a threshold device.

    PubMed

    Lisboa, C; Muñoz, V; Beroiza, T; Leiva, A; Cruz, E

    1994-07-01

    The usefulness of inspiratory muscle training (IMT) in chronic airflow limitation (CAL) patients is a controversial issue, mainly due to differences in the training load. To further evaluate this aspect, we studied the effect of the magnitude of the load using a threshold pressure trainer. Ten CAL patients (5 males, 5 females) 67 +/- 2 yrs (mean +/- SEM) and forced expiratory volume in one second (FEV1) 36 +/- 2% pred, were trained for 30 min a day using a load of 30% of their maximal inspiratory mouth pressure (PImax) (Group 1). Another 10 CAL patients (5 males, 5 females), 73 +/- 2 yrs and FEV1 37 +/- 2% pred), were trained using only 12% of their PImax (Group 2). Training was assessed by PImax, inspiratory muscle power output (IMPO), sustainable inspiratory pressure (SIP), maximal inspiratory flow rate (VImax), pattern of breathing during loaded breathing, Mahler's dyspnoea score, and the 6 min walking distance (6MWD). After 5 weeks of training, Group 1 exhibited significant increments in: PImax (34 +/- 11%); IMPO (92 +/- 16%); SIP (36 +/- 9%); and VImax (34 +/- 13%). Dyspnoea was also reduced, and the 6MWD increased by 48 +/- 22 m. We observed no significant changes in Group 2. During loaded breathing, Group 1 showed a significant increment in tidal volume (VT) and mean inspiratory flow (VT/TI), and a reduction in inspiratory time (TI). In Group 2, VT and VT/TI also increased significantly, but the breathing frequency increased with a reduction of expiratory time.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7925905

  20. Inspiratory muscle training compared with other rehabilitation interventions in adults with chronic obstructive pulmonary disease: a systematic literature review and meta-analysis.

    PubMed

    Crowe, Jean; Reid, W Darlene; Geddes, E Lynne; O'Brien, Kelly; Brooks, Dina

    2005-09-01

    The purpose of this systematic review was to determine the effect of inspiratory muscle training (IMT) (alone or combined with exercise and/or pulmonary rehabilitation) compared to other rehabilitation interventions such as: exercise, education, other breathing techniques or exercise and/or pulmonary rehabilitation among adults with chronic obstructive pulmonary disease (COPD). A systematic review of the literature on IMT and COPD was conducted according to the Cochrane Collaboration protocol. Inclusion criteria for the review included randomized controlled trials, published in English, comparing IMT or combined IMT and exercise/pulmonary rehabilitation with other rehabilitation interventions such as general exercise, education, other breathing techniques or exercise/pulmonary rehabilitation among adults with COPD. 274 articles were retrieved, and 16 met the inclusion criteria. Seven meta-analyses were performed that compared targeted or threshold IMT to exercise (n = 3) or to education (n = 4). Results showed significant improvements in inspiratory muscle strength and endurance, and in the dyspnea scale on a quality of life measure, for participants in the IMT versus education group. In other instances where meta-analyses could not be performed, a qualitative review was performed. IMT results in improved inspiratory muscle strength and endurance compared to education. Further trials are required to investigate the effect of IMT (or combined IMT) compared to other rehabilitation inventions for outcomes such as dyspnea, exercise tolerance, and quality of life. PMID:17146997

  1. [Effect of methylphenidatum on inspiratory muscles function in patients with chronic obstructive pulmonary disease and its mechanism].

    PubMed

    Wang, Y; Luo, Y; Chen, W; Yuan, Y; He, T; Zeng, J

    1997-03-01

    To have a better understanding of the effect of methylphenidatum on inspiratory muscles function, we studied the respiratory force parameters of 70 patients with chronic obstructive pulmonary disease by intravenous infusion methylphenidatum in a randomized controlled clinical trial. The indices of respiratory force parameter included maximal inspiratory mouth pressure (MIP), maximal midinspiratory flow (MMIF), forced inspiratory capacity (FIC), maximal works of inspiration (Wimax) and airway occlusion pressure (P0.1), etc. Aminophylline and Nikethamidi were chosen as controls. The results showed that MIP, MMIF, FIC, Wimax, P0.1 and minute ventilation (Vr) were significantly increased after administration of methylphenidatum and aminophylline. There were no significant differences in MIP, MMIF, FIC and Wimax after administration of Nikethamidi, but P0.1 was significantly increased and the increase was higher than that after administration of methylphenidatum and aminophylline groups. We conclude that methylphenidatum can significantly improve the function of inspiratory muscles as aminophylline can do. PMID:10684069

  2. The value of multiple tests of respiratory muscle strength

    PubMed Central

    Steier, Joerg; Kaul, Sunny; Seymour, John; Jolley, Caroline; Rafferty, Gerrard; Man, William; Luo, Yuan M; Roughton, Michael; Polkey, Michael I; Moxham, John

    2007-01-01

    Background Respiratory muscle weakness is an important clinical problem. Tests of varying complexity and invasiveness are available to assess respiratory muscle strength. The relative precision of different tests in the detection of weakness is less clear, as is the value of multiple tests. Methods The respiratory muscle function tests of clinical referrals who had multiple tests assessed in our laboratories over a 6‐year period were analysed. Thresholds for weakness for each test were determined from published and in‐house laboratory data. The patients were divided into three groups: those who had all relevant measurements of global inspiratory muscle strength (group A, n = 182), those with full assessment of diaphragm strength (group B, n = 264) and those for whom expiratory muscle strength was fully evaluated (group C, n = 60). The diagnostic outcome of each inspiratory, diaphragm and expiratory muscle test, both singly and in combination, was studied and the impact of using more than one test to detect weakness was calculated. Results The clinical referrals were primarily for the evaluation of neuromuscular diseases and dyspnoea of unknown cause. A low maximal inspiratory mouth pressure (Pimax) was recorded in 40.1% of referrals in group A, while a low sniff nasal pressure (Sniff Pnasal) was recorded in 41.8% and a low sniff oesophageal pressure (Sniff Poes) in 37.9%. When assessing inspiratory strength with the combination of all three tests, 29.6% of patients had weakness. Using the two non‐invasive tests (Pimax and Sniff Pnasal) in combination, a similar result was obtained (low in 32.4%). Combining Sniff Pdi (low in 68.2%) and Twitch Pdi (low in 67.4%) reduced the diagnoses of patients with diaphragm weakness to 55.3% in group B. 38.3% of the patients in group C had expiratory muscle weakness as measured by maximum expiratory pressure (Pemax) compared with 36.7% when weakness was diagnosed by cough gastric pressure (Pgas), and 28.3% when

  3. Inspiratory muscle performance relative to the anaerobic threshold in patients with COPD.

    PubMed

    Wanke, T; Formanek, D; Lahrmann, H; Merkle, M; Rauscher, H; Zwick, H

    1993-09-01

    Rehabilitation programmes in chronic obstructive pulmonary disease (COPD) require exercise training above the anaerobic threshold. However, not all COPD patients develop metabolic acidosis during exercise. The hypothesis of this study was that non-exercise variables, characterizing the mechanical load on the inspiratory muscles during breathing at rest, can be used to reliably predict which patients with COPD are not able to develop metabolic acidosis during exercise. Thirty participants with COPD performed a symptom-limited cycle ergometer test. The oesophageal pressure/time index (PTIoes: the product of pressure magnitude and duration), the mean rate of pressure development during inspiration (Poes/TI), and the mean airway resistance (Raw)/maximal oesophageal pressure (Poesmax) ratio served as indices for the mechanical load on the inspiratory muscles. The oxygen uptake (VO2) at which plasma standard bicarbonate was seen to decrease from its baseline value was taken as the anaerboic threshold (AT). Mean Raw was significantly higher in those patients in whom the AT could not be detected. No other lung function parameters measured at rest allowed the accurate selection of those patients who did or did not develop exercise metabolic acidosis. On the other hand, Raw/Poesmax, PTIoes and Poes/TI were significantly different in the two patient groups. Additionally, whereas in the patient group with identifiable AT exercise hyperpnoea produced a non-linear increase of Poes/TI with respect to PTIoes above the AT, in the patient group without identifiable AT there was a linear relationship between Poes/TI and PTIoes throughout exercise. We conclude that the determination of inspiratory muscle load indices at rest may be useful in pulmonary rehabilitation programmes, for identifying those patients with COPD who do not develop exercise induced metabolic acidosis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8224135

  4. Pulmonary Rehabilitation Using Modified Threshold Inspiratory Muscle Trainer (IMT) in Patients with Tetraplegia.

    PubMed

    Yasar, Funda; Tasci, Canturk; Savci, Sema; Tozkoparan, Ergun; Deniz, Omer; Balkan, Arzu; Bilgic, Hayati

    2012-01-01

    It is aimed to present the usefulness of inspiratory muscle trainer (IMT) in treatment of a 20-year-old male patient with diaphragmatic paralysis and tetraplegia due to spinal cord injury (SCI), and supporting effect of IMT in recovering from respiratory failure by rendering his diaphragm functions. The treatment was applied through the tracheostomy cannula by a modified IMT device. After applying IMT for three weeks, it was observed that the diaphragm recovered its functions in electromyography (EMG) test. As a result, in this study, we present a case where a patient could live without any respiratory device for the rest of his life with the help of modified IMT. PMID:22536264

  5. Effects of Abdominal Stimulation during Inspiratory Muscle Training on Respiratory Function of Chronic Stroke Patients

    PubMed Central

    Jung, Ju-hyeon; Shim, Je-myung; Kwon, Hae-yeon; Kim, Ha-roo; Kim, Bo-in

    2014-01-01

    [Purpose] The purpose of the present study was to verify a new method for improving respiratory functions by applying both abdominal stimulation and inspiratory muscle training (IMT) to train the inspiratory muscle and the expiratory muscle simultaneously, to improve the efficiency of IMT of chronic stroke patients. [Subjects] Eighteen stroke patients were randomly assigned to an experimental group (n = 9) and a control group (n = 9). [Methods] The experimental group was administered IMT with abdominal stimulation, and the control group was administered only IMT. During the intervention period, the experimental group and control group received training 20 min/day, 3 times/wk, for 4 weeks. To examine the lung functions of the subjects, FVC, FEV1, PEF, and FEF25–75 were measured using an electronic spirometer. The diaphragm thickness ratio was calculated from measurements made with a 7.5-MHz linear probe ultrasonic imaging system. [Result] The experimental group and the control group showed significant increases in diaphragm thickness ratio on the paretic side, but not on the non-paretic side. With regard to lung function, the experimental group showed significant increases in FEV1, PEF, and FEF25–75. The changes between before and after the intervention in the two groups were compared with each other, and the results showed significant differences in FEV1 and PEF. [Conclusion] The present study identified that IMT accompanied by abdominal stimulation improved the pulmonary function of chronic stroke patients. PMID:24567679

  6. Protocol: inspiratory muscle training for promoting recovery and outcomes in ventilated patients (IMPROVe): a randomised controlled trial

    PubMed Central

    Leditschke, I Anne; Paratz, Jennifer D; Boots, Robert J

    2012-01-01

    Introduction Inspiratory muscle weakness is a known consequence of mechanical ventilation and a potential contributor to difficulty in weaning from ventilatory support. Inspiratory muscle training (IMT) reduces the weaning period and increases the likelihood of successful weaning in some patients. However, it is not known how this training affects the residual inspiratory muscle fatigability following successful weaning nor patients' quality of life or functional outcomes. Methods and analysis This dual centre study includes two concurrent randomised controlled trials of IMT in adult patients who are either currently ventilator-dependent (>7 days) (n=70) or have been recently weaned from mechanical ventilation (>7 days) in the past week (n=70). Subjects will be stable, alert and able to actively participate and provide consent. There will be concealed allocation to either treatment (IMT) or usual physiotherapy (including deep breathing exercises without a resistance device). Primary outcomes are inspiratory muscle fatigue resistance and maximum inspiratory pressures. Secondary outcomes are quality of life (Short Form-36v2, EQ-5D), functional status (Acute Care Index of Function), rate of perceived exertion (Borg Scale), intensive care length of stay (days), post intensive care length of stay (days), rate of reintubation (%) and duration of ventilation (days). Ethics and dissemination Ethics approval has been obtained from relevant institutions, and results will be published with a view to influencing physiotherapy practice in the management of long-term ventilator-dependent patients to accelerate weaning and optimise rehabilitation outcomes. Trial registration number ACTRN12610001089022. PMID:22389363

  7. Effects of a 10-week inspiratory muscle training program on lower-extremity mobility in people with multiple sclerosis: a randomized controlled trial.

    PubMed

    Pfalzer, Lucinda; Fry, Donna

    2011-01-01

    Pulmonary muscle weakness is common in ambulatory people with multiple sclerosis (MS) and may lead to deficits in mobility function. The purpose of this study was to examine the effect of a 10-week home-based exercise program using an inspiratory muscle threshold trainer (IMT) on the results of four lower-extremity physical performance tests in people with MS. The study design was a two-group (experimental-control), pretest-posttest study. Outcome measures consisted of pulmonary function measures including maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and maximal voluntary ventilation (MVV), and the following lower-extremity physical performance measures: the 6-Minute Walk (6MW) distance, gait velocity (GV), the Sit-to-Stand Test (SST), the Functional Stair Test (FST), and a balance test (BAL). A total of 46 ambulatory participants (Expanded Disability Status Scale [EDSS] score, 2.0-6.5) with MS were randomly assigned to an intervention group (mean EDSS score, 4.1) that received 10 weeks of home-based inspiratory muscle training or a nontreatment control group (mean EDSS score, 3.2). Of the original 46 participants, 20 intervention group participants and 19 control group participants completed the study. Compared with the control group, the intervention group made significantly greater gains in inspiratory muscle strength (P = .003) and timed balance scores (P = .008). A nonsignificant improvement in 6MW distance (P = .086) was also noted in the IMT-trained group as compared with the control group. This is the first study directly linking improvement in respiratory function to improvement in physical performance function in people with mild-to-moderate disability due to MS. PMID:24453703

  8. Evaluation of the THRESHOLD trainer for inspiratory muscle endurance training: comparison with the weighted plunger method.

    PubMed

    Johnson, P H; Cowley, A J; Kinnear, W J

    1996-12-01

    Inspiratory muscle training (IMT) has been shown to enhance exercise performance. The weighted plunger (WP) system of inspiratory threshold loading is the most commonly used method of IMT, but is expensive and cumbersome. We have evaluated a commercially available portable spring-loaded IMT device, the THRESHOLD trainer. The WP and THRESHOLD trainer devices were evaluated with their opening pressures set, in random order, at 10, 20, 30 and 40 cmH2O. Using an airpump, pressure at the valve inlet was recorded at the point at which the valve opened, and at airflow rates of 20, 40, 60, 80 and 100 L.min-1. Ten THRESHOLD trainers were then compared using the same opening pressures and airflow rates. Finally, 10 patients with stable chronic heart failure (CHF) inspired, in random order, through the WP and THRESHOLD trainer for 4 min each. The pressure-time product (PTP) was calculated for each 4 min period, to compare the work performed on inspiring through each device. The mean measured opening pressures for the WP set at 10, 20, 30 and 40 cmH2O, were 9.0, 19.3, 27.9 and 39.2 cmH2O, respectively, and there was little change over the range of flow tested. Corresponding values for the THRESHOLD trainer were 7.5, 16.9, 26.2 and 39.1 cmH2O, with the pressure being closer to the set pressure as flow increased to that seen in clinical practice. The 10 different trainers tested performed very similarly to one another. Work performed (as measured by PTP) on inspiring through the WP and THRESHOLD trainer was not significantly different. Although less accurate than the weighted plunger, the THRESHOLD trainer is an inexpensive device of consistent quality. In a clinical setting it would be a satisfactory option for inspiratory muscle training in most patients, but less so in patients with very low inspiratory flow rates. PMID:8980985

  9. In normal subjects bracing impairs the function of the inspiratory muscles.

    PubMed

    Prandi, E; Couture, J; Bellemare, F

    1999-05-01

    Normal subjects can increase their capacity to sustain hyperpnoea by bracing their arms on fixed objects, a procedure which is also known to reduce dyspnoea in patients with chronic obstructive pulmonary disease (COPD). In the present study, it was tested whether bracing per se could improve the function of the diaphragm. The effect of bracing on diaphragm function was studied in six normal subjects by recording changes in oesophageal (delta Poes) and transdiaphragmatic (delta Pdi) pressure during inspiratory capacity (IC) manoeuvres in the seated and upright postures, and in the seated posture, also during bilateral phrenic nerve stimulation (BPNS) at functional residual capacity (FRC). The pattern of ribcage motion and deformation associated with bracing and with diaphragm contraction was also evaluated using inductance plethysmography and magnetometers. Bracing increased FRC by >300 mL and reduced IC by approximately 200 mL, in both postures. Delta Pdi during BPNS decreased on average by 15% indicating an impaired diaphragmatic function. The ribcage was deformed with bracing and was more distortable during BPNS. In conclusion, in normal subjects, bracing impairs the function of the inspiratory muscles and reduces ribcage stability. These negative effects cannot explain the improved capacity to sustain hyperpnoea when the arms are braced. PMID:10414407

  10. [Clinical effects of inspiratory muscle training in patients with chronic airflow limitation].

    PubMed

    Lisboa, C; Villafranca, C; Pertuzé, J; Leiva, A; Repetto, P

    1995-09-01

    The clinical role of inspiratory muscle training (IMT) in chronic obstructive pulmonary disease (COPD) has not been established, because data on its clinical effect is scarce and controversial. To further investigate these aspects we studied 20 COPD patients (FEV1 37 +/- 3% P) who were randomly and double blindly trained for 30 minutes a day during 10 weeks using a threshold inspiratory trainer with either 30% (group 1) or 10% (group 2) of PIMax as a training load. The training load was crossed after each patient completed 10 weeks of training. Effects were assessed through changes in PIMax, dyspnea through the transition dyspnea index (ITD) and the respiratory effort with Borg's score. Walking capacity was measured with the six minutes walking distance test (6WD) and depression symptoms with Beck's score. Daily life activities were also assessed. Results showed that after 10 weeks of IMT, PIMax increased in both groups (p < 0.05), dyspnea improved in group 1 as compared to group 2 (p < 0.04), 6WD increased significantly in patients of group 1, who also complained of less dyspnea (p < 0.05). Depression scores fell significantly in group 2. Daily activities improved more in group 1. After the crossover patients in group 1 disclosed a significant deterioration in PIMax whereas group 2 disclosed significant improvements in PIMax, dyspnea and 6WD. We conclude that IMT using a threshold device with 30% PIMax is a useful procedure for the treatment of severe COPD patients. PMID:8728734

  11. Effect of Simulated Microgravity and Lunar Gravity on Human Inspiratory Muscle Function: 'Selena-T' 2015 Study.

    PubMed

    Segizbaeva, M O; Aleksandrova, N P; Donina, Z A; Baranova, E V; Katuntsev, V P; Tarasenkov, G G; Baranov, V M

    2016-01-01

    As a part of the multi-disciplinary "SELENA-T"-2015 Bed Rest Study, we investigated the pattern of inspiratory muscles fatigue in 22 healthy male subjects during incremental exercise test to exhaustion before and after 21 days of hypokinesia evoked by bed rest. Hypokinesia consisted of head-down bed rest (HDBR) at a minus 6° angle, simulating microgravity present on orbiting spacecraft, in 10 subjects. The remaining 12 subjects spent the first 5 days of hypokinesia in HDBR position and the subsequent 16 days in head-up bed rest (HUBR) at a plus 9.6° angle, as a presumed analog of lunar gravity that is six times less than Earth's gravity. Maximal inspiratory pressure (MIP) and electromyograms (EMG) of the diaphragm (D), parasternal (PS), sternocleidomastoid (SCM), and scalene (S) muscles served as indices of inspiratory muscle function. Before both HDBR and HUBR, exercise decreased MIP and centroid frequency (fc) of EMG (D, PS, SCM, and S) power spectrum (p < 0.05). After 3 weeks of HDBR, but not HUBR, inspiratory muscles fatigue was more expressed compared with control (p < 0.05). We conclude that HDBR lowers inspiratory muscles resistance to fatigue during high-intensity exercise while HUBR has no such effect. These changes may limit maximal ventilation and may contribute to exercise intolerance observed after prolonged simulated microgravity. The physiological mechanisms of respiratory muscle dysfunction after HDBR consist primarily of postural effects, and are not due only to hypokinesia. PMID:27241510

  12. Diaphragmatic amplitude and accessory inspiratory muscle activity in nasal and mouth-breathing adults: a cross-sectional study.

    PubMed

    Trevisan, Maria Elaine; Boufleur, Jalusa; Soares, Juliana Corrêa; Haygert, Carlos Jesus Pereira; Ries, Lilian Gerdi Kittel; Corrêa, Eliane Castilhos Rodrigues

    2015-06-01

    The purpose of this study was to evaluate the electromyographic activity of the accessory inspiratory muscles and the diaphragmatic amplitude (DA) in nasal and mouth-breathing adults. The study evaluated 38 mouth-breathing (MB group) and 38 nasal-breathing (NB group) adults, from 18 to 30years old and both sexes. Surface electromyography (sEMG) was used to evaluate the amplitude and symmetry (POC%) of the sternocleidomastoid (SCM) and upper trapezius (UT) muscles at rest, during nasal slow inspiration at Lung Total Capacity (LTC) and, during rapid and abrupt inspiration: Sniff, Peak Nasal Inspiratory Flow (PNIF) and Maximum Inspiratory Pressure (MIP). M-mode ultrasonography assessed the right diaphragm muscle amplitude in three different nasal inspirations: at tidal volume (TV), Sniff and inspiration at LTC. The SCM activity was significantly lower in the MB group during Sniff, PNIF (p<0.01, Mann-Whitney test) and MIP (p<0.01, t-test). The groups did not differ during rest and inspiration at LTC, regarding sEMG amplitude and POC%. DA was significantly lower in the MB group at TV (p<0.01, Mann-Whitney) and TLC (p=0.03, t-test). Mouth breathing reflected on lower recruitment of the accessory inspiratory muscles during fast inspiration and lower diaphragmatic amplitude, compared to nasal breathing. PMID:25900327

  13. The effect of inspiratory muscle training upon maximum lactate steady-state and blood lactate concentration.

    PubMed

    McConnell, Alison K; Sharpe, Graham R

    2005-06-01

    Several studies have reported that improvements in endurance performance following respiratory muscle training (RMT) are associated with a decrease in blood lactate concentration ([Lac](B)). The present study examined whether pressure threshold inspiratory muscle training (IMT) elicits an increase in the cycling power output corresponding to the maximum lactate steady state (MLSS). Using a double-blind, placebo-controlled design, 12 healthy, non-endurance-trained male participants were assigned in equal numbers to an experimental (IMT) or sham training control (placebo) group. Cycling power output at MLSS was initially identified using a lactate minimum protocol followed by a series of constant power output rides (2.5% increments) of 29.5 min duration; MLSS was reassessed following six weeks of IMT or sham IMT. Maximum inspiratory mouth pressure increased significantly (26%) in the IMT group, but remained unchanged in the placebo group. The cycling power output corresponding to MLSS remained unchanged in both groups after the intervention. After IMT, [Lac](B) decreased significantly at MLSS power in the IMT group [-1.17 (1.01) mmol l(-1) after 29.5 min of cycling; mean (SD)], but remained unchanged in the placebo group [+0.37 (1.66) mmol l(-1)]. These data support previous observations that IMT results in a decrease in [Lac](B )at a given intensity of exercise. That such a decrease in [Lac](B) was not associated with a substantial (>2.5%) increase in MLSS power is a new finding suggesting that RMT-induced increases in exercise tolerance and reductions in [Lac](B) are not ascribable to a substantial increase in the 'lactate threshold'. PMID:15765241

  14. The influence of inspiratory and expiratory muscle training upon rowing performance.

    PubMed

    Griffiths, Lisa A; McConnell, Alison K

    2007-03-01

    We investigated the effect of 4 week of inspiratory (IMT) or expiratory muscle training (EMT), as well as the effect of a subsequent 6 week period of combined IMT/EMT on rowing performance in club-level oarsmen. Seventeen male rowers were allocated to either an IMT (n = 10) or EMT (n = 7) group. The groups underwent a 4 week IMT or EMT program; after interim testing, both groups subsequently performed a 6 week program of combined IMT/EMT. Exercise performance and physiological responses to exercise were measured at 4 and 10 week during an incremental rowing ergometer 'step-test' and a 6 min all-out (6MAO) effort. Pressure threshold respiratory muscle training was undertaken at the 30 repetition maximum load (approximately 50% of the peak inspiratory and expiratory mouth pressure, P (Imax) or P (Emax), respectively). P (Imax) increased during the IMT phase of the training in the IMT group (26%, P < 0.001) and was accompanied by an improvement in mean power during the 6MAO (2.7%, P = 0.015). Despite an increase in P (Emax) by the end of the intervention (31%, P = 0.03), the EMT group showed no significant changes in any performance parameters during either the 'step-test' or 6MAO. There were no significant changes in breathing pattern or the metabolic response to the 6MAO test in either group, but the IMT group showed a small decrease in HR (2-5%, P = 0.001). We conclude that there were no significant additional changes following combined IMT/EMT. IMT improved rowing performance, but EMT and subsequent combined IMT/EMT did not. PMID:17186299

  15. Airway occlusion pressure and diaphragm global electromyogram analysis for evaluation of inspiratory muscle drive and neuromechanical coupling in cattle.

    PubMed

    Desmecht, D J; Linden, A S; Rollin, F A; Lekeux, P M

    1994-06-01

    Although healthy and diseased bovine respiratory tracts have been intensively studied during the last years, to the authors' knowledge, there have been no attempts to objectively examine the inspiratory drive from the brain to the nerves and muscles and its transformation in pressure. Such technique would be useful in assessing the possibility of altered ventilatory drive or inspiratory muscle fatigue in the context of an animal with ventilatory failure. The relation among ventilation, airway opening occlusion pressure generated 100 milliseconds after onset of inspiration (Pawo100ms) and 6 indexes describing diaphragmatic electromyographic activity (EMGdi) recorded via implanted fishhooks was evaluated during free and impeded CO2 rebreathing in 6 young bulls. The best significant linear correlations (r > 0.8) with inspiratory center afferent stimulation, as judged by end-tidal CO2 concentration in expired air, were found for Pawo100ms, peak moving time average or variance EMGdi, and mean integrated EMGdi, whatever had been the respiratory impedance. However, with an inspiratory load, Pawo100ms responses systematically had greater increase for a given change in the driving EMGdi, implying dependence of the former not only on neural input, but also on configurational factors that determine inspiratory muscle excitation-pressure generation couplings. The reproducibility of EMGdi absolute values and changes was satisfactory up to 10 hours, but could not be repeated from one day to the other. It was concluded that, provided the constancy of the electrical coupling of the recording system to the tissue being studied is ensured, specific EMGdi and Pawo100ms values correlate reliably with amount of CO2 during free and loaded breathing.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7944009

  16. The 400- and 800-m Track Running Induces Inspiratory Muscle Fatigue in Trained Female Middle-Distance Runners.

    PubMed

    Ohya, Toshiyuki; Yamanaka, Ryo; Hagiwara, Masahiro; Oriishi, Marie; Suzuki, Yasuhiro

    2016-05-01

    Inspiratory muscle fatigue (IMF) may limit exercise performance. A few studies have reported that IMF occurs after short-duration swimming exercise, but whether short-duration running can induce IMF remains unclear. Intra-abdominal pressure is increased during running through diaphragmatic activation to stabilize the spine during movements of the upper limbs. This occurs along with the increased inspiratory muscle effort associated with increased respirations during exercise; thus, we hypothesized that short-duration running exercise would induce IMF. To test this hypothesis, we measured maximal inspiratory pressure (MIP) before and after 400- and 800-m track running sessions. Eight female middle-distance (400, 800 m) runners performed a 400- and 800-m running test. Maximal inspiratory pressure was measured before and after each test using a portable autospirometer. The mean MIPs were significantly lower after running than before running; values obtained were 107 ± 25 vs. 97 ± 27 cmH2O (p = 0.01, effect size [ES] = 0.65) and 108 ± 26 vs. 92 ± 27 cmH2O (p = 0.01, ES = 0.74) before vs. after the 400- and 800-m tests, respectively. The mean MIP after the 800-m test was significantly lower than after the 400-m test (p = 0.04, ES = 0.48). There was no correlation between IMF value and running time (r = 0.53 and r = -0.28 for either the 400- and 800-m tests, respectively; p > 0.05). In conclusion, IMF occurs after short-duration running exercise. Coaches could consider prescribing inspiratory muscle training or warm-up in an effort to reduce the inevitable IMF associated with maximal effort running. PMID:26422611

  17. Sniff and Muller manoeuvres to measure diaphragmatic muscle strength.

    PubMed

    Prigent, Hélène; Orlikowski, David; Fermanian, Christophe; Lejaille, Michèle; Falaize, Line; Louis, Alain; Fauroux, Brigitte; Lofaso, Frédéric

    2008-12-01

    We hypothesized that peak values of oesophageal (Poes) and transdiaphragmatic pressure (Pdi) swings during a maximal sniff manoeuvre and a maximal static inspiratory manoeuvre (Muller manoeuvre) are comparable or give complementary information for assessing diaphragmatic and global inspiratory muscle strength. We studied 98 patients with suspected diaphragmatic dysfunction. Poes and Pdi swings were measured during maximal sniff manoeuvres (sniff), maximal Muller manoeuvres (max), and cervical magnetic phrenic nerve stimulation (cervical Tw). Eighty eight patients were able to perform both volitional manoeuvres. Among them, mean Poes sniff was significantly higher than mean Poes max (48.7+/-28.7 cm H(2)O vs. 42.9+/-27.4 cm H(2)O, p<0.05) and mean Pdi sniff was higher than mean Pdi max (49.2+/-35.1cm H(2)O vs. 42.9+/-33.3 cm H(2)O, respectively, p=0.05). Cervical Pdi Tw correlated better with Pdi sniff (p<0.0001, r=0.62) than with Pdi max (p<0.0001, r=0.44). Poes and Pdi swings were greatest during the sniff manoeuvre in 42 patients (48%) and during the Muller manoeuvre in 29 patients (33%). Among the 17 remaining patients, nine had the greatest Poes swing during a maximal sniff manoeuvre and the greatest Pdi swing during a maximal static inspiratory manoeuvre; the opposite occurred in the other eight patients. The combination of Muller manoeuvre and sniff manoeuvre increased the diagnosis of normal diaphragmatic strength from 18 patients (20%) to 21 patients (24%), and the additional analysis of cervical Pdi Tw further increased the diagnosis of normal diaphragmatic strength to 27 patients (31%). In conclusion, though sniff manoeuvre gave significantly higher values than Muller manoeuvre, both volitional manoeuvres and cervical Pdi Tw are complementary and should be used in combination to evaluate diaphragmatic muscle strength. PMID:18708281

  18. The Pilates Method increases respiratory muscle strength and performance as well as abdominal muscle thickness.

    PubMed

    Giacomini, Mateus Beltrame; da Silva, Antônio Marcos Vargas; Weber, Laura Menezes; Monteiro, Mariane Borba

    2016-04-01

    The aim of this study was to verify the effects of the Pilates Method (PM) training program on the thickness of the abdominal wall muscles, respiratory muscle strength and performance, and lung function. This uncontrolled clinical trial involved 16 sedentary women who were assessed before and after eight weeks of PM training. The thickness of the transversus abdominis (TrA), internal oblique (IO) and external oblique (EO) muscles was assessed. The respiratory muscle strength was assessed by measuring the maximum inspiratory (MIP) and expiratory (MEP) pressure. The lung function and respiratory muscle performance were assessed by spirometry. An increase was found in MIP (p = 0.001), MEP (p = 0.031), maximum voluntary ventilation (p = 0.020) and the TrA (p < 0.001), IO (p = 0.002) and EO (p < 0.001) thickness after the PM program. No alterations in lung function were found. These findings suggest that the PM program promotes abdominal wall muscle hypertrophy and an increase in respiratory muscle strength and performance, preventing weakness in abdominal muscles and dysfunction in ventilatory mechanics, which could favor the appearance of illnesses. PMID:27210841

  19. Medicinal clays improve the endurance of loaded inspiratory muscles in COPD: a randomized clinical trial of nonpharmacological treatment

    PubMed Central

    Baldi, Simonetta; Pinna, Gian Domenico; Bruschi, Claudio; Caldara, Fabrizio; Maestri, Roberto; Dacosto, Elena; Rezzani, Antonella; Popovich, Ermanno; Bellinzona, Ezio; Crotti, Paola; Montemartini, Silvia; Fracchia, Claudio

    2015-01-01

    Background Inspiratory resistive breathing (IRB) challenges affect respiratory muscle endurance in healthy individuals, which is considered to be an interleukin 6 (IL-6)–dependent mechanism. Whether nonpharmacological thermal therapies promote the endurance of loaded inspiratory muscles in chronic obstructive pulmonary disease (COPD) is unclear. The objectives of this study were to compare the effects of two thermal interventions on endurance time (ET) and plasma IL-6 concentration following an IRB challenge. Methods This study was a randomized, parallel-group, unblinded clinical trial in a single-center setting. Forty-two patients (aged 42–76 years) suffering from mild to severe COPD participated in this study. Both groups completed 12 sessions of the mud bath therapy (MBT) (n=22) or leisure thermal activity (LTA) (n=19) in a thermal spa center in Italy. Pre- and postintervention spirometry, maximum inspiratory pressure, and plasma mediators were obtained and ET and endurance oxygen expenditure (VO2Endur) were measured following IRB challenge at 40% of maximum inspiratory pressure. Results There was no difference in ΔIL-6 between the intervention groups. But, IRB challenge increased cytokine IL-6 plasma levels systematically. The effect size was small. A statistically significant treatment by IRB challenge effect existed in ET, which significantly increased in the MBT group (P=0.003). In analysis of covariance treatment by IRB challenge analysis with LnVO2Endur as the dependent variable, ΔIL-6 after intervention predicted LnVO2Endur in the MBT group, but not in the LTA group. Adverse events occurred in two individuals in the MBT group, but they were mainly transient. One patient in the LTA group dropped out. Conclusion MBT model improves ET upon a moderate IRB challenge, indicating the occurrence of a training effect. The LnVO2Endur/ΔIL-6 suggests a physiologic adaptive mechanism in respiratory muscles of COPD patients allocated to treatment. Both thermal

  20. Inspiratory muscle training enhances pulmonary O(2) uptake kinetics and high-intensity exercise tolerance in humans.

    PubMed

    Bailey, Stephen J; Romer, Lee M; Kelly, James; Wilkerson, Daryl P; DiMenna, Fred J; Jones, Andrew M

    2010-08-01

    Fatigue of the respiratory muscles during intense exercise might compromise leg blood flow, thereby constraining oxygen uptake (Vo(2)) and limiting exercise tolerance. We tested the hypothesis that inspiratory muscle training (IMT) would reduce inspiratory muscle fatigue, speed Vo(2) kinetics and enhance exercise tolerance. Sixteen recreationally active subjects (mean + or - SD, age 22 + or - 4 yr) were randomly assigned to receive 4 wk of either pressure threshold IMT [30 breaths twice daily at approximately 50% of maximum inspiratory pressure (MIP)] or sham treatment (60 breaths once daily at approximately 15% of MIP). The subjects completed moderate-, severe- and maximal-intensity "step" exercise transitions on a cycle ergometer before (Pre) and after (Post) the 4-wk intervention period for determination of Vo(2) kinetics and exercise tolerance. There were no significant changes in the physiological variables of interest after Sham. After IMT, baseline MIP was significantly increased (Pre vs. Post: 155 + or - 22 vs. 181 + or - 21 cmH(2)O; P < 0.001), and the degree of inspiratory muscle fatigue was reduced after severe- and maximal-intensity exercise. During severe exercise, the Vo(2) slow component was reduced (Pre vs. Post: 0.60 + or - 0.20 vs. 0.53 + or - 0.24 l/min; P < 0.05) and exercise tolerance was enhanced (Pre vs. Post: 765 + or - 249 vs. 1,061 + or - 304 s; P < 0.01). Similarly, during maximal exercise, the Vo(2) slow component was reduced (Pre vs. Post: 0.28 + or - 0.14 vs. 0.18 + or - 0.07 l/min; P < 0.05) and exercise tolerance was enhanced (Pre vs. Post: 177 + or - 24 vs. 208 + or - 37 s; P < 0.01). Four weeks of IMT, which reduced inspiratory muscle fatigue, resulted in a reduced Vo(2) slow-component amplitude and an improved exercise tolerance during severe- and maximal-intensity exercise. The results indicate that the enhanced exercise tolerance observed after IMT might be related, at least in part, to improved Vo(2) dynamics, presumably as a

  1. Relationship Between Respiratory Muscle Strength and Conventional Sarcopenic Indices in Young Adults: A Preliminary Study

    PubMed Central

    Ro, Hee Joon; Lee, Sang Yoon; Seo, Kyung Mook; Kang, Si Hyun; Suh, Hoon Chang

    2015-01-01

    Objective To investigate the relationships between respiratory muscle strength and conventional sarcopenic indices such as skeletal muscle mass and limb muscle strength. Methods Eighty-nine young adult volunteers who had no history of medical or musculoskeletal disease were enrolled. Skeletal muscle mass was measured by bioelectrical impedance analysis and expressed as a skeletal muscle mass index (SMI). Upper and lower limb muscle strength were evaluated by hand grip strength (HGS) and isometric knee extensor muscle strength, respectively. Peak expiratory flow (PEF), maximal inspiratory pressure (MIP), and maximal expiratory pressure (MEP) were evaluated using a spirometer to demonstrate respiratory muscle strength. The relationships between respiratory muscle strength and sarcopenic indices were investigated using Pearson correlation coefficients and multiple linear regression analysis adjusted by age, height, and body mass index. Results MIP showed positive correlations with SMI (r=0.457 in men, r=0.646 in women; both p<0.01). MIP also correlated with knee extensor strength (p<0.01 in both sexes) and HGS (p<0.05 in men, p<0.01 in women). However, PEF and MEP had no significant correlations with these sarcopenic variables. In multivariate regression analysis, MIP was the only independent factor related to SMI (p<0.01). Conclusion Among the respiratory muscle strength variables, MIP was the only value associated with skeletal muscle mass. PMID:26798601

  2. Extubation process in bed-ridden elderly intensive care patients receiving inspiratory muscle training: a randomized clinical trial

    PubMed Central

    Cader, Samária Ali; de Souza Vale, Rodrigo Gomes; Zamora, Victor Emmanuel; Costa, Claudia Henrique; Dantas, Estélio Henrique Martin

    2012-01-01

    Background The purpose of this study was to evaluate the extubation process in bed-ridden elderly intensive care patients receiving inspiratory muscle training (IMT) and identify predictors of successful weaning. Methods Twenty-eight elderly intubated patients in an intensive care unit were randomly assigned to an experimental group (n = 14) that received conventional physiotherapy plus IMT with a Threshold IMT® device or to a control group (n = 14) that received only conventional physiotherapy. The experimental protocol for muscle training consisted of an initial load of 30% maximum inspiratory pressure, which was increased by 10% daily. The training was administered for 5 minutes, twice daily, 7 days a week, with supplemental oxygen from the beginning of weaning until extubation. Successful extubation was defined by the ventilation time measurement with noninvasive positive pressure. A vacuum manometer was used for measurement of maximum inspiratory pressure, and the patients’ Tobin index values were measured using a ventilometer. Results The maximum inspiratory pressure increased significantly (by 7 cm H2O, 95% confidence interval [CI] 4–10), and the Tobin index decreased significantly (by 16 breaths/ min/L, 95% CI −26 to 6) in the experimental group compared with the control group. The Chi-squared distribution did not indicate a significant difference in weaning success between the groups (χ2 = 1.47; P = 0.20). However, a comparison of noninvasive positive pressure time dependence indicated a significantly lower value for the experimental group (P = 0.0001; 95% CI 13.08–18.06). The receiver-operating characteristic curve showed an area beneath the curve of 0.877 ± 0.06 for the Tobin index and 0.845 ± 0.07 for maximum inspiratory pressure. Conclusion The IMT intervention significantly increased maximum inspiratory pressure and significantly reduced the Tobin index; both measures are considered to be good extubation indices. IMT was associated with a

  3. Respiratory muscle strength in asthmatic children

    PubMed Central

    Marcelino, Alessandra Maria Farias Cavalcante; da Cunha, Daniele Andrade; da Cunha, Renata Andrade; da Silva, Hilton Justino

    2012-01-01

    Summary Introduction: Changes in the respiratory system of asthmatics are also due to the mechanical disadvantage caused by the increased airway resistance. Objective: The study aims to evaluate the respiratory muscle strength and nutritional status of asthmatic children. Method: This is a prospective descriptive and transversal study with 50 children aged 7 to 12 years, who were placed into 2 groups, asthmatic and non-asthmatic. Respiratory muscle strength was evaluated on the basis of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). The nutritional status was evaluated by measuring the anthropometric data, including height, weight, and body mass index (BMI). The findings were subjected to analysis of variance, chi-square, and Student's t test, and p-values < 0.05 was considered statistically significant. Results: In our comparisons, we observed statistically significantly lower values for age, weight, and height in asthmatic patients: 8.52 ± 1.49 years, 30.62 ± 7.66 kg, and 129.85 ± 10.24 cm, respectively, vs. non-asthmatic children(9.79 ± 1.51 years, 39.92 ± 16.57 kg, and 139.04 ± 11.62 cm, respectively). There was no significant increase in MIP and MEP between the groups: MIP was -84.96 ± 27.52 cmH2O for the asthmatic group and -88.56 ± 26.50 cmH2O for the non-asthmatic group, and MEP was 64.48 ± 19.23 cmH2O for asthmatic children and +66.72 ± 16.56 cmH2O for non-asthmatics. Conclusion: There was no statistically significant difference between groups, but we observed that MIP and MEP were slightly higher in the non-asthmatic group than in the asthmatic group. PMID:25991978

  4. Preoperative inspiratory muscle training to prevent postoperative pulmonary complications in patients undergoing esophageal resection (PREPARE study): study protocol for a randomized controlled trial

    PubMed Central

    2014-01-01

    Background Esophageal resection is associated with a high incidence of postoperative pneumonia. Respiratory complications account for almost half of the readmissions to the critical care unit. Postoperative complications can result in prolonged hospital stay and consequently increase healthcare costs. In cardiac surgery a preoperative inspiratory muscle training program has shown to prevent postoperative pneumonia and reduce length of hospital stay. While in some surgical centers inspiratory muscle training is already used in the preoperative phase in patients undergoing esophageal resection, the added value of this intervention on the reduction of pulmonary complications has not yet been investigated in large surgical populations other than cardiac surgery in a randomized and controlled study design. Methods/Design The effect of a preoperative inspiratory muscle training program on the incidence of postoperative pneumonia in patients undergoing esophageal resection will be studied in a single blind multicenter randomized controlled trial (the PREPARE study). In total 248 patients (age >18 years) undergoing esophageal resection for esophageal cancer will be included in this study. They are randomized to either usual care or usual care with an additional inspiratory muscle training intervention according to a high-intensity protocol which is performed with a tapered flow resistive inspiratory loading device. Patients have to complete 30 dynamic inspiratory efforts twice daily for 7 days a week until surgery with a minimum of 2 weeks. The starting training load will be aimed to be 60% of maximal inspiratory pressure and will be increased based on the rate of perceived exertion. The main study endpoint is the incidence of postoperative pneumonia. Secondary objectives are to evaluate the effect of preoperative inspiratory muscle training on length of hospital stay, duration of mechanical ventilation, incidence of other postoperative (pulmonary) complications

  5. The effect of home-based inspiratory muscle training on exercise capacity, exertional dyspnea and pulmonary function in COPD patients

    PubMed Central

    Bavarsad, Maryam Bakhshandeh; Shariati, Abdolali; Eidani, Esmaeil; Latifi, Mahmud

    2015-01-01

    Background: Chronic obstructive pulmonary disease (COPD) is currently the fourth cause of mortality worldwide. Patients with COPD experience periods of dyspnea, fatigue, and disability, which impact on their life. The objective of this study was to investigate the effect of short-term inspiratory muscle training on exercise capacity, exertional dyspnea, and pulmonary lung function. Materials and Methods: A randomized, controlled trial was performed. Thirty patients (27 males, 3 females) with mild to very severe COPD were randomly assigned to a training group (group T) or to a control group (group C). Patients in group T received training for 8 weeks (15 min/day for 6 days/week) with flow-volumetric inspiratory exerciser named (Respivol). Each patient was assessed before and after 8 weeks of training for the following clinical parameters: exercise capacity by 6-min walking test (6MWT), exertional dyspnea by Borg scale, and pulmonary lung function by spirometry. Patients used training together with medical treatment. The data were analyzed using paired t-test and independent t-test. Results: Results showed statistically significant increase in 6MWT at the end of the training from 445.6 ± 22.99 to 491.06 ± 17.67 meters? (P < 0.001) and statistically significant decrease in dyspnea from 3.76 ± 0.64 to 1.13 ± 0.36 (P = 0.0001) in the training group but not in the control group. The values for exercise capacity and dyspnea improved after 8 weeks in group T in comparison with group C (P = 0.001 and P = 0.0001, respectively). No changes were observed in any measure of pulmonary function in both groups. Conclusions: Short-term inspiratory muscle training has beneficial effects on exercise capacity and exertional dyspnea in COPD patients. PMID:26457101

  6. Inspiratory muscle fatigue affects latissimus dorsi but not pectoralis major activity during arms only front crawl sprinting.

    PubMed

    Lomax, Mitch; Tasker, Louise; Bostanci, Ozgur

    2014-08-01

    The purpose of this study was to determine whether inspiratory muscle fatigue (IMF) affects the muscle activity of the latissimus dorsi and pectoralis major during maximal arms only front crawl swimming. Eight collegiate swimmers were recruited to perform 2 maximal 20-second arms only front crawl sprints in a swimming flume. Both sprints were performed on the same day, and IMF was induced 30 minutes after the first (control) sprint. Maximal inspiratory and expiratory mouth pressures (PImax and PEmax, respectively) were measured before and after each sprint. The median frequency (MDF) of the electromyographic signal burst was recorded from the latissimus dorsi and pectoralis major during each 20-second sprint along with stroke rate and breathing frequency. Median frequency was assessed in absolute units (Hz) and then referenced to the start of the control sprint for normalization. After IMF inducement, stroke rate increased from 56 ± 4 to 59 ± 5 cycles per minute, and latissimus dorsi MDF fell from 67 ± 11 Hz at the start of the sprint to 61 ± 9 Hz at the end. No change was observed in the MDF of the latissimus dorsi during the control sprint. Conversely, the MDF of the pectoralis major shifted to lower frequencies during both sprints but was unaffected by IMF. As the latter induced fatigue in the latissimus dorsi, which was not otherwise apparent during maximal arms only control sprinting, the presence of IMF affects the activity of the latissimus dorsi during front crawl sprinting. PMID:24402450

  7. Asymmetry of Muscle Strength in Elite Athletes

    ERIC Educational Resources Information Center

    Drid, Patrik; Drapsin, Miodrag; Trivic, Tatjana; Lukac, Damir; Obadov, Slavko; Milosevic, Zoran

    2009-01-01

    "Study aim": To determine muscle strength variables in elite judoists and wrestlers since thigh muscle strength and bilaterally balanced flexor-to-extensor ratio minimise injury risk and are desirable for achieving sport successes. "Material and methods": Judoists, wrestlers and untrained subjects, 10 each, were subjected to isokinetic strength…

  8. Inspiratory muscle training improves cycling time-trial performance and anaerobic work capacity but not critical power.

    PubMed

    Johnson, Michael A; Sharpe, Graham R; Brown, Peter I

    2007-12-01

    We examined whether inspiratory muscle training (IMT) improved cycling time-trial performance and changed the relationship between limit work (W (lim)) and limit time (T (lim)), which is described by the parameters critical power (CP) and anaerobic work capacity (AWC). Eighteen male cyclists were assigned to either a pressure-threshold IMT or sham hypoxic-training placebo (PLC) group. Prior to and following a 6 week intervention subjects completed a 25-km cycling time-trial and three constant-power tests to establish the W (lim)-T (lim) relationship. Constant-power tests were prescribed to elicit exercise intolerance within 3-10 (Ex1), 10-20 (Ex2), and 20-30 (Ex3) min. Maximal inspiratory mouth pressure increased by (mean +/- SD) 17.1 +/- 12.2% following IMT (P < 0.01) and was accompanied by a 2.66 +/- 2.51% improvement in 25-km time-trial performance (P < 0.05); there were no changes following PLC. Constant-power cycling endurance was unchanged following PLC, as was CP (pre vs. post: 249 +/- 32 vs. 250 +/- 32 W) and AWC (30.7 +/- 12.7 vs. 30.1 +/- 12.5 kJ). Following IMT Ex1 and Ex3 cycling endurance improved by 18.3 +/- 15.1 and 15.3 +/- 19.1% (P < 0.05), respectively, CP was unchanged (264 +/- 62 vs. 263 +/- 61 W), but AWC increased from 24.8 +/- 5.6 to 29.0 +/- 8.4 kJ (P < 0.05). In conclusion, these data provide novel evidence that improvements in constant-power and cycling time-trial performance following IMT in cyclists may be explained, in part, by an increase in AWC. PMID:17874123

  9. Impact of backpack type on respiratory muscle strength and lung function in children.

    PubMed

    Vieira, Ana Christina; Ribeiro, Fernando

    2015-01-01

    We examine the influence of backpack type on lung function and respiratory muscle strength in children. Thirty-seven children were assessed for lung function and inspiratory and expiratory muscle strength under four randomly determined conditions: unloaded erect standing and three conditions carrying 15% of the child's body weight. In these three conditions, children carried the weight on a backpack with bilateral shoulder straps carried over both shoulders, on a backpack with bilateral shoulder straps carried over one shoulder and on a backpack with a mono shoulder strap. Significantly lower forced vital capacity, forced expiratory volume in one second and maximal expiratory pressure were observed when children carried a backpack with a mono shoulder strap compared to the unloaded standing position. In conclusion, the restrictive effect and the decrease in expiratory muscle strength were more pronounced for the backpack with a mono shoulder strap, suggesting that a double strap backpack is preferable to a mono shoulder strap backpack. Practitioner summary: There is little known about the effect of schoolbags on respiratory muscle function. We investigated the influence of backpack type on lung function and respiratory muscle strength. A backpack with a mono shoulder strap created a restrictive effect and a decrease in strength, suggesting that a double strap backpack is preferable to a mono shoulder strap backpack. PMID:25584722

  10. Sniff nasal inspiratory pressure in patients with chronic obstructive pulmonary disease.

    PubMed

    Uldry, C; Janssens, J P; de Muralt, B; Fitting, J W

    1997-06-01

    In subjects with normal lung mechanics, inspiratory muscle strength can be reliably and easily assessed by the sniff nasal inspiratory pressure (SNIP), which is the pressure measured in an occluded nostril during a maximal sniff performed through the contralateral nostril. The aim of this study was to assess the validity of the SNIP in patients with chronic obstructive pulmonary disease (COPD), where pressure transmission from alveoli to upper airways is likely to be dampened. Twenty eight patients with COPD were studied (mean forced expiratory volume in one second (FEV1) = 36% of predicted). The SNIP and the sniff oesophageal pressure (sniff Poes) were measured simultaneously during maximal sniffs, and were compared to the maximal inspiratory pressure obtained against an occlusion (MIP). All measurements were performed from functional residual capacity in the sitting position. The ratio SNIP/sniff Poes was 0.80, and did not correlate with the degree of airflow limitation. The ratio MIP/sniff Poes was 0.87, and the ratio SNIP/MIP was 0.97. Inspiratory muscle weakness, as defined by a low sniff Poes, was present in 17 of the 28 patients. A false diagnosis of weakness was made in eight patients when MIP was considered alone, in four when SNIP was considered alone, and in only three patients when MIP and SNIP were combined. We conclude that both the sniff nasal inspiratory pressure and the maximal inspiratory pressure moderately underestimate sniff oesophageal pressure in chronic obstructive pulmonary disease. Although suboptimal in this condition, the sniff nasal inspiratory pressure appears useful to complement the maximal inspiratory pressure for assessing inspiratory muscle strength in patients with chronic obstructive pulmonary disease. PMID:9192931

  11. Importance and challenges of measuring intrinsic foot muscle strength

    PubMed Central

    2012-01-01

    Background Intrinsic foot muscle weakness has been implicated in a range of foot deformities and disorders. However, to establish a relationship between intrinsic muscle weakness and foot pathology, an objective measure of intrinsic muscle strength is needed. The aim of this review was to provide an overview of the anatomy and role of intrinsic foot muscles, implications of intrinsic weakness and evaluate the different methods used to measure intrinsic foot muscle strength. Method Literature was sourced from database searches of MEDLINE, PubMed, SCOPUS, Cochrane Library, PEDro and CINAHL up to June 2012. Results There is no widely accepted method of measuring intrinsic foot muscle strength. Methods to estimate toe flexor muscle strength include the paper grip test, plantar pressure, toe dynamometry, and the intrinsic positive test. Hand-held dynamometry has excellent interrater and intrarater reliability and limits toe curling, which is an action hypothesised to activate extrinsic toe flexor muscles. However, it is unclear whether any method can actually isolate intrinsic muscle strength. Also most methods measure only toe flexor strength and other actions such as toe extension and abduction have not been adequately assessed. Indirect methods to investigate intrinsic muscle structure and performance include CT, ultrasonography, MRI, EMG, and muscle biopsy. Indirect methods often discriminate between intrinsic and extrinsic muscles, but lack the ability to measure muscle force. Conclusions There are many challenges to accurately measure intrinsic muscle strength in isolation. Most studies have measured toe flexor strength as a surrogate measure of intrinsic muscle strength. Hand-held dynamometry appears to be a promising method of estimating intrinsic muscle strength. However, the contribution of extrinsic muscles cannot be excluded from toe flexor strength measurement. Future research should clarify the relative contribution of intrinsic and extrinsic muscles

  12. Respiratory muscle strength test: is it realistic in young children?

    PubMed Central

    Heinzmann-Filho, João Paulo; Donadio, Márcio Vinícius Fagundes

    2015-01-01

    Objective: To determine the success rate of the manovacuometry test in children between 4 and 12 years of age. Methods: Cross-sectional study involving children and adolescents from 4 to 12 years of age, enrolled in three basic education schools. All subjects had the anthropometric and respiratory muscle strength (maximum inspiratory pressure and maximum expiratory pressure) data measured. Students whose parents did not authorize participation or who did not want to undergo the test were excluded. The test was considered successful when the subject reached acceptability (no air leaks) and reproducibility (variation <10% between the two major maneuvers) criteria established by guidelines. Failure was defined when subjects did not meet the above criteria. Data were expressed as mean and standard deviation and the categorical variables in absolute and relative frequency. The comparison between proportions was performed using the chi-square test. Results: We included 196 children and adolescents, mean age of 8.4±2.5 years, 53.1% female. The success rate of the manovacuometry test in children and adolescents evaluated was 92.3%. When comparing the differences between the success rates of preschool children with those children and adolescents of school age, there was a significantly lower success rate in the pre-school (85.1%) group compared to the school group (94.6%) (p=0.032). However, no significant differences (p=0.575) were found when gender comparisons were performed. Conclusions: The manovacuometry test showed a high success rate in both preschool and school population assessed. Furthermore, the rate of success appears to be related to aging. PMID:26137867

  13. Autism Severity and Muscle Strength: A Correlation Analysis

    ERIC Educational Resources Information Center

    Kern, Janet K.; Geier, David A.; Adams, James B.; Troutman, Melissa R.; Davis, Georgia; King, Paul G.; Young, John L.; Geier, Mark R.

    2011-01-01

    The current study examined the relationship between muscle strength, as measured by hand grip strength, and autism severity, as measured by the Childhood Autism Rating Scale (CARS). Thirty-seven (37) children with a diagnosis of autism spectrum disorder (ASD) were evaluated using the CARS and then tested for hand muscle strength using a hand grip…

  14. Oxygen uptake kinetics and maximal aerobic power are unaffected by inspiratory muscle training in healthy subjects where time to exhaustion is extended.

    PubMed

    Edwards, A M; Cooke, C B

    2004-10-01

    The aim of this study was to determine whether 4 weeks of inspiratory muscle training (IMT) would be accompanied by alteration in cardiopulmonary fitness as assessed through moderate intensity oxygen uptake (V(.)O(2)) kinetics and maximal aerobic power (V(.)O(2max)). Eighteen healthy males agreed to participate in the study [training group (Tra) n=10, control group (Con) n=8]. Measurements of spirometry and maximal static inspiratory mouth pressure ( PI(max)) were taken pre- and post-training in addition to: (1) an incremental test to volitional exhaustion, (2) three square-wave transitions from walking to running at a moderate intensity (80% ventilatory threshold) and (3) a maximal aerobic constant-load running test to volitional fatigue for the determination of time to exhaustion ( T(lim)). Training was performed using an inspiratory muscle trainer (Powerbreathe). There were no significant differences in spirometry either between the two groups or when comparing the post- to pre-training results within each group. Mean PI(max) increased significantly in Tra ( P<0.01) and showed a trend for improvement ( P<0.08) in Con. Post-training T(lim) was significantly extended in both Tra [232.4 (22.8) s and 242.8 (20.1) s] ( P<0.01) and Con [224.5 (19.6) and 233.5 (12.7) s] ( P<0.05). Post-training T(lim) was significantly extended in Tra compared to Con ( P<0.05). In conclusion, the most plausible explanation for the stability in V(.)O(2) kinetics and V(.)O(2max) following IMT is that it is due to insufficient whole-body stress to elicit either central or peripheral cardiopulmonary adaptation. The extension of post-training T(lim) suggests that IMT might be useful as a stratagem for producing greater volumes of endurance work at high ventilatory loads, which in turn could improve cardiopulmonary fitness. PMID:15322855

  15. Differences in muscle strength after ACL reconstruction do not influence cardiorespiratory responses to isometabolic exercise

    PubMed Central

    Andrade, Marília S.; Lira, Claudio A. B.; Vancini, Rodrigo L.; Nakamoto, Fernanda P.; Cohen, Moisés; Silva, Antonio C.

    2014-01-01

    Objectives To investigate whether the muscle strength decrease that follows anterior cruciate ligament (ACL) reconstruction would lead to different cardiorespiratory adjustments during dynamic exercise. Method Eighteen active male subjects were submitted to isokinetic evaluation of knee flexor and extensor muscles four months after ACL surgery. Thigh circumference was also measured and an incremental unilateral cardiopulmonary exercise test was performed separately for both involved and uninvolved lower limbs in order to compare heart rate, oxygen consumption, minute ventilation, and ventilatory pattern (breath rate, tidal volume, inspiratory time, expiratory time, tidal volume/inspiratory time) at three different workloads (moderate, anaerobic threshold, and maximal). Results There was a significant difference between isokinetic extensor peak torque measured in the involved (116.5±29.1 Nm) and uninvolved (220.8±40.4 Nm) limbs, p=0.000. Isokinetic flexor peak torque was also lower in the involved limb than in the uninvolved limb (107.8±15.4 and 132.5±26.3 Nm, p=0.004, respectively). Lower values were also found in involved thigh circumference as compared with uninvolved limb (46.9±4.3 and 48.5±3.9 cm, p=0.005, respectively). No differences were found between the lower limbs in any of the variables of the incremental cardiopulmonary tests at all exercise intensities. Conclusions Our findings indicate that, four months after ACL surgery, there is a significant deficit in isokinetic strength in the involved limb, but these differences in muscle strength requirement do not produce differences in the cardiorespiratory adjustments to exercise. Based on the hypotheses from the literature which explain the differences in the physiological responses to exercise for different muscle masses, we can deduce that, after 4 months of a rehabilitation program after an ACL reconstruction, individuals probably do not present differences in muscle oxidative and peripheral

  16. Effects of muscle extension strength exercise on trunk muscle strength and stability of patients with lumbar herniated nucleus pulposus.

    PubMed

    Jeon, Kyoungkyu; Kim, Taeyoung; Lee, Sang-Ho

    2016-05-01

    [Purpose] The purpose of this study was to provide the data for constructing an integrated exercise program to help restore muscle strength and stability through extension strength exercise in adult females with lumbar disc herniation. [Subjects and Methods] An 8-week exercise program for lumbar muscle extension strength and stabilization was performed by 26 females older than 20 with lumbar disc herniation findings. [Results] Significant differences were found in lumbar extension muscle strength at every angle of lumbar flexion after participation in the 8-week stabilization exercise program; but there was no significant difference in the weight distribution index. [Conclusion] An integrated exercise program aiming to strengthen lumbar spine muscles, reduce pain and stabilize the trunk can help to maintain muscle strength and balance. In addition, improvement in extension strength is expected to be helpful in daily life by securing the range of joint motion and improving the strength and stability. PMID:27313342

  17. Effects of muscle extension strength exercise on trunk muscle strength and stability of patients with lumbar herniated nucleus pulposus

    PubMed Central

    Jeon, Kyoungkyu; Kim, Taeyoung; Lee, Sang-Ho

    2016-01-01

    [Purpose] The purpose of this study was to provide the data for constructing an integrated exercise program to help restore muscle strength and stability through extension strength exercise in adult females with lumbar disc herniation. [Subjects and Methods] An 8-week exercise program for lumbar muscle extension strength and stabilization was performed by 26 females older than 20 with lumbar disc herniation findings. [Results] Significant differences were found in lumbar extension muscle strength at every angle of lumbar flexion after participation in the 8-week stabilization exercise program; but there was no significant difference in the weight distribution index. [Conclusion] An integrated exercise program aiming to strengthen lumbar spine muscles, reduce pain and stabilize the trunk can help to maintain muscle strength and balance. In addition, improvement in extension strength is expected to be helpful in daily life by securing the range of joint motion and improving the strength and stability. PMID:27313342

  18. Vital capacity, respiratory muscle strength, and pulmonary gas exchange during long-duration exposure to microgravity.

    PubMed

    Prisk, G Kim; Fine, Janelle M; Cooper, Trevor K; West, John B

    2006-08-01

    Extended exposure to microgravity (microG) is known to reduce strength in weight-bearing muscles and was also reported to reduce respiratory muscle strength. Short- duration exposure to microG reduces vital capacity (VC), a surrogate measure for respiratory muscle strength, for the first few days, with little change in O2 uptake, ventilation, or end-tidal partial pressures. Accordingly we measured VC, maximum inspiratory and expiratory pressures, and indexes of pulmonary gas exchange in 10 normal subjects (9 men, 1 woman, 39-52 yr) who lived on the International Space Station for 130-196 days in a normoxic, normobaric atmosphere. Subjects were studied four times in the standing and supine postures preflight at sea level at 1 G, approximately monthly in microG, and multiple times postflight. VC in microG was essentially unchanged compared with preflight standing [5.28 +/- 0.08 liters (mean +/- SE), n = 187; 5.24 +/- 0.09, n = 117, respectively; P = 0.03] and considerably greater than that measured supine in 1G (4.96 +/- 0.10, n = 114, P < 0.001). There was a trend for VC to decrease after the first 2 mo of microG, but there were no changes postflight. Maximum respiratory pressures in microG were generally intermediate to those standing and supine in 1G, and importantly they showed no decrease with time spent in microG. O2 uptake and CO2 production were reduced (approximately 12%) in extended microG, but inhomogeneity in the lung was not different compared with short-duration exposure to microG. The results show that VC is essentially unchanged and respiratory muscle strength is maintained during extended exposure to microG, and metabolic rate is reduced. PMID:16601306

  19. Objective Evaluation of Muscle Strength in Infants with Hypotonia and Muscle Weakness

    ERIC Educational Resources Information Center

    Reus, Linda; van Vlimmeren, Leo A.; Staal, J. Bart; Janssen, Anjo J. W. M.; Otten, Barto J.; Pelzer, Ben J.; Nijhuis-van der Sanden, Maria W. G.

    2013-01-01

    The clinical evaluation of an infant with motor delay, muscle weakness, and/or hypotonia would improve considerably if muscle strength could be measured objectively and normal reference values were available. The authors developed a method to measure muscle strength in infants and tested 81 typically developing infants, 6-36 months of age, and 17…

  20. Comparative effects of plasma exchange and pyridostigmine on respiratory muscle strength and breathing pattern in patients with myasthenia gravis.

    PubMed Central

    Goti, P.; Spinelli, A.; Marconi, G.; Duranti, R.; Gigliotti, F.; Pizzi, A.; Scano, G.

    1995-01-01

    BACKGROUND--Pyridostigmine, an acetylcholinesterase antagonist, is useful in improving respiratory function in patients with myasthenia gravis. More recently, plasma exchange has been employed in myasthenia gravis because it acts presumably by removal of circulating antibodies against acetylcholine receptors. Surprisingly, comparative data on the effects of pyridostigmine and plasma exchange on lung volumes, respiratory muscle strength, and ventilatory control system in patients with myasthenia gravis are lacking. METHODS--Nine consecutive patients with grade IIb myasthenia gravis were studied under control conditions and after a therapeutic dose of pyridostigmine. In a second study the patients were re-evaluated a few days after a cycle of plasma exchange, before taking pyridostigmine. In each subject pulmonary volumes, inspiratory (MIP) and expiratory (MEP) muscle force, and respiratory muscle strength, calculated as average MIP and MEP as percentages of their predicted values, were measured. The ventilatory control system was evaluated in terms of volume (tidal volume, VT) and time (inspiratory time, TI, and total time, TTOT) components of the respiratory cycle. Mean inspiratory flow (VT/TI)--that is, the "driving"--and TI/TTOT--that is, the "timing"--components of ventilation were also measured. RESULTS--In each patient treatment relieved weakness and tiredness, and dyspnoea grade was reduced with plasma exchange. Following treatment, vital capacity (VC) increased on average by 9.7% with pyridostigmine and by 14% with plasma exchange, and MIP increased by 18% and 26%, respectively. In addition, with plasma exchange but not with pyridostigmine forced expiratory volume in one second (FEV1) increased by 16% and MEP increased by 24.5%, while functional residual capacity (FRC) decreased a little (6.8%). The change in respiratory muscle strength was related to change in VC (r2 = 0.48). With plasma exchange, VT increased by 18.6% and VT/TI increased by 13.5%, while

  1. Knee muscle strength in multiple sclerosis: relationship with gait characteristics

    PubMed Central

    Güner, Senem; Hagharı, Sema; Inanıcı, Fatma; Alsancak, Serap; Aytekın, Gokhan

    2015-01-01

    [Purpose] To investigate the relationship between isokinetic knee muscle strength and kinematic, kinetic and spatiotemporal gait parameters of patients with multiple sclerosis (MS). [Subjects and Methods] Twenty-nine MS patients (mean age 31.5±6.5) were investigated in this study. The isokinetic knee muscle strength and gait parameters of MS patients with moderate and severe disability, as determined by the expanded disability status scale (EDSS): EDSS=1–4.5 (n=22, moderate disability) and EDSS>4.5 (n=7, severe disability) were measured. [Results] Isokinetic knee muscle strength, kinematic, kinetic and spatiotemporal gait parameters differed between moderate (EDSS=1–4.5, n=22) and severe disability (EDSS>4.5, n=7). The correlation between each of gait speed, stride length, total range of knee joint movement and the four strength parameters (minimum and maximum quadriceps and hamstring muscle strengths) were significant for the MS group as a whole. Within subgroups, the correlation between minimum hamstring strength and total range of knee movement was significant only in group EDSS>4.5; minimum hamstring correlated with peak knee extensor moment in group EDSS=1–4.5, but at a reduced level of significance. [Conclusion] The present study revealed significant correlations between gait characteristics and isokinetic strength parameters of the quadriceps and hamstring muscles. Our study suggests that rehabilitation protocols for MS patients should include a critical strength training programme particularly for the hamstring and quadriceps muscles. PMID:25931736

  2. Arginylation of myosin heavy chain regulates skeletal muscle strength

    PubMed Central

    Cornachione, Anabelle S.; Leite, Felipe S.; Wang, Junling; Leu, Nicolae A.; Kalganov, Albert; Volgin, Denys; Han, Xuemei; Xu, Tao; Cheng, Yu-Shu; Yates, John R. R.; Rassier, Dilson E.; Kashina, Anna

    2014-01-01

    Protein arginylation is a post-translational modification with an emerging global role in the regulation of actin cytoskeleton. To test the role of arginylation in the skeletal muscle, we generated a mouse model with Ate1 knockout driven by skeletal muscle-specific creatine kinase (Ckmm) promoter. Such Ckmm-Ate1 mice were viable and outwardly normal, however their skeletal muscle strength was significantly reduced compared to the control. Mass spectrometry of the isolated skeletal myofibrils showed a limited set of proteins arginylated on specific sites, including myosin heavy chain. Atomic force microscopy measurements of the contractile strength in individual myofibrils and isolated myosin filaments from these mice showed a significant reduction of contractile forces, which, in the case of the myosin filaments could be fully rescued by re-arginylation with purified Ate1. Our results demonstrate that arginylation regulates force production in the muscle and exerts a direct effect on muscle strength through arginylation of myosin. PMID:25017061

  3. [Development of Muscle Strength Evaluating System Based on Mobile Platform].

    PubMed

    Xu, Xiulin; Yao, Xiaoming; Xu, Xijiao; Hu, Xiaohui

    2015-08-01

    The development of muscle strength evaluating system based on Android system was developed in this research. The system consists of a lower unit and an intelligent mobile terminal. The pressure sensor of the lower unit was used to collect muscle strength parameters. And the parameters were sent to the Android device through the wireless Bluetooth serial port. Then the Android device would send the parameters to the doctor monitored platform through the Internet. The system realized analyzing the muscle strength parameters and real-time displaying them. After it ran on the Android mobile phones, it showed an effective result which proved that the system combined with mobile platform could make more convenient for the patients to assess their own muscle strength. It also provided reliable data references for doctors to know the patients' rehabilitation condition and to make the next rehabilitation plan. PMID:26710452

  4. Hormone Therapy and Skeletal Muscle Strength: A Meta-Analysis

    PubMed Central

    Greising, Sarah M.; Baltgalvis, Kristen A.; Warren, Gordon L.

    2009-01-01

    Background Our objective was to perform a systematic review and meta-analysis of the research literature that compared muscle strength in postmenopausal women who were and were not on estrogen-based hormone therapy (HT). Methods Twenty-three relevant studies were found. Effect sizes (ESs) were calculated as the standardized mean difference, and meta-analyses were completed using a random effects model. Results HT was found to result in a small beneficial effect on muscle strength in postmenopausal women (overall ES = 0.23; p = .003) that equated to an ∼5% greater strength for women on HT. Among the 23 studies, various muscle groups were assessed for strength, and those that benefitted the most were the thumb adductors (ES = 1.14; p < .001). Ten studies that compared muscle strength in rodents that were and were not estradiol deficient were also analyzed. The ES for absolute strength was moderate but not statistically significant (ES = 0.44; p = .12), whereas estradiol had a large effect on strength normalized to muscle size (ES = 0.66; p = .03). Conclusion Overall, estrogen-based treatments were found to beneficially affect strength. PMID:19561145

  5. Development of a Theory-Based Intervention to Increase Prescription of Inspiratory Muscle Training by Health Professionals in the Management of People with Chronic Obstructive Pulmonary Disease

    PubMed Central

    Li, Linda C.; Reid, W. Darlene

    2011-01-01

    ABSTRACT Purpose: The purpose of this paper is twofold: (1) to provide an overview of the literature on barriers to evidence-based practice (EBP) and the effectiveness of implementation interventions in health care; and (2) to outline the development of an implementation intervention for improving the prescription of inspiratory muscle training (IMT) by physical therapists and other health professionals for people with chronic obstructive pulmonary disease (COPD). Summary of Key Points: Individuals, organizations, and the research itself present barriers to EBP in physical therapy. Despite the evidence supporting the use of IMT, this treatment continues to be under-used in managing COPD. Current health services research shows that traditional information-based approaches to implementation, such as didactic lectures, do not adequately address the challenges health professionals face when trying to make changes in practice. We propose the development of a theory-based intervention to improve health professionals' use of IMT in the management of COPD. It is postulated that a behavioural intervention, based on the theory of planned behaviour (TPB), may be more effective than an information-based strategy in increasing the prescription of IMT by health professionals. Conclusion: TPB may be used to understand the antecedents of health professionals' behaviour and to guide the development of implementation interventions. Further research is needed to evaluate the effectiveness of this proposed intervention in the management of people with COPD. PMID:22654237

  6. Examination of Strength Training and Detraining Effects in Expiratory Muscles

    ERIC Educational Resources Information Center

    Baker, Susan; Davenport, Paul; Sapienza, Christine

    2005-01-01

    Purpose: The purpose of this study was to determine strength gains following expiratory muscle strength training (EMST) and to determine detraining effects when the training stimulus is removed. Method: Thirty-two healthy participants were enrolled in an EMST program. Sixteen participants trained for 4 weeks (Group 1) and 16 participants trained…

  7. Muscle Strength And Golf Performance: A Critical Review

    PubMed Central

    Torres-Ronda, Lorena; Sánchez-Medina, Luis; González-Badillo, Juan J.

    2011-01-01

    Golf has become an increasingly popular sport and a growing body of research trying to identify its main physical requirements is being published. The aim of this review was twofold: first, to examine the existing scientific literature regarding strength training and golf in healthy, non-injured, subjects; and second, to reach conclusions that could provide information on how to design more effective strength training programs to improve golf performance as well as directions for future research. Studies which analyzed the relationship between muscle strength, swing performance variables (club head speed, driving distance, ball speed) and skill (handicap, score) were reviewed. Changes in swing performance following different strength training programs were also investigated. Finally, a critical analysis about the methodologies used was carried out. The results of the reviewed studies seem to indicate that: 1) a positive relationship exists between handicap and swing performance (even though few studies have investigated this issue); 2) there is a positive correlation between skill (handicap and/or score) and muscle strength; and 3) there is a relationship between driving distance, swing speed, ball speed and muscle strength. Results suggest that training leg-hip and trunk power as well as grip strength is especially relevant for golf performance improvement. Studies that analyzed variations in swing performance following resistance-only training programs are scarce, thus it is difficult to prove whether the observed improvements are attributable to changes in strength levels. Many of the studies reviewed presented some methodological errors in their design and not all strength assessment protocols seemed appropriate. Further studies should determine muscle strength needs in relation to final swing performance, using well designed experiments and strict isoinertial assessment protocols which adequately relate to specific golf motion, age and skill level. More

  8. Muscle strength and golf performance: a critical review.

    PubMed

    Torres-Ronda, Lorena; Sánchez-Medina, Luis; González-Badillo, Juan J

    2011-01-01

    Golf has become an increasingly popular sport and a growing body of research trying to identify its main physical requirements is being published. The aim of this review was twofold: first, to examine the existing scientific literature regarding strength training and golf in healthy, non-injured, subjects; and second, to reach conclusions that could provide information on how to design more effective strength training programs to improve golf performance as well as directions for future research. Studies which analyzed the relationship between muscle strength, swing performance variables (club head speed, driving distance, ball speed) and skill (handicap, score) were reviewed. Changes in swing performance following different strength training programs were also investigated. Finally, a critical analysis about the methodologies used was carried out. The results of the reviewed studies seem to indicate that: 1) a positive relationship exists between handicap and swing performance (even though few studies have investigated this issue); 2) there is a positive correlation between skill (handicap and/or score) and muscle strength; and 3) there is a relationship between driving distance, swing speed, ball speed and muscle strength. Results suggest that training leg-hip and trunk power as well as grip strength is especially relevant for golf performance improvement. Studies that analyzed variations in swing performance following resistance-only training programs are scarce, thus it is difficult to prove whether the observed improvements are attributable to changes in strength levels. Many of the studies reviewed presented some methodological errors in their design and not all strength assessment protocols seemed appropriate. Further studies should determine muscle strength needs in relation to final swing performance, using well designed experiments and strict isoinertial assessment protocols which adequately relate to specific golf motion, age and skill level. More

  9. Abdominal muscle and quadriceps strength in chronic obstructive pulmonary disease

    PubMed Central

    Man, W; Hopkinson, N; Harraf, F; Nikoletou, D; Polkey, M; Moxham, J

    2005-01-01

    Background: Quadriceps muscle weakness is common in chronic obstructive pulmonary disease (COPD) but is not observed in a small hand muscle (adductor pollicis). Although this could be explained by reduced activity in the quadriceps, the observation could also be explained by anatomical location of the muscle or fibre type composition. However, the abdominal muscles are of a similar anatomical and fibre type distribution to the quadriceps, although they remain active in COPD. Cough gastric pressure is a recently described technique that assesses abdominal muscle (and hence expiratory muscle) strength more accurately than traditional techniques. A study was undertaken to test the hypothesis that more severe weakness exists in the quadriceps than in the abdominal muscles of patients with COPD compared with healthy elderly controls. Methods: Maximum cough gastric pressure and quadriceps isometric strength were measured in 43 patients with stable COPD and 25 healthy elderly volunteers matched for anthropometric variables. Results: Despite a significant reduction in mean quadriceps strength (29.9 kg v 41.2 kg; 95% CI –17.9 to –4.6; p = 0.001), cough gastric pressure was preserved in patients with COPD (227.3 cm H2O v 204.8 cm H2O; 95% CI –5.4 to 50.6; p = 0.11). Conclusions: Abdominal muscle strength is preserved in stable COPD outpatients in the presence of quadriceps weakness. This suggests that anatomical location and fibre type cannot explain quadriceps weakness in COPD. By inference, we conclude that disuse and consequent deconditioning are important factors in the development of quadriceps muscle weakness in COPD patients, or that activity protects the abdominal muscles from possible systemic myopathic processes. PMID:15923239

  10. Evaluation of Respiratory Muscle Strength in Mouth Breathers: Clinical Evidences

    PubMed Central

    Andrade da Cunha, Renata; Andrade da Cunha, Daniele; Assis, Roberta Borba; Bezerra, Luciana Ângelo; Justino da Silva, Hilton

    2013-01-01

    Introduction The child who chronically breathes through the mouth may develop a weakness of the respiratory muscles. Researchers and clinical are seeking for methods of instrumental evaluation to gather complementary data to clinical evaluations. With this in mind, it is important to evaluate breathing muscles in the child with Mouth Breathing. Objective To develop a review to investigate studies that used evaluation methods of respiratory muscle strength in mouth breathers. Data Synthesis  The authors were unanimous in relation to manovacuometry method as a way to evaluate respiratory pressures in Mouth Breathing children. Two of them performed with an analog manovacuometer and the other one, digital. The studies were not evaluated with regard to the method efficacy neither the used instruments. Conclusion There are few studies evaluating respiratory muscle strength in Mouth Breathing people through manovacuometry and the low methodological rigor of the analyzed studies hindered a reliable result to support or refuse the use of this technique. PMID:25992108

  11. Lower limb muscle strength is associated with functional performance and quality of life in patients with systemic sclerosis

    PubMed Central

    Lima, Tatiana R. L.; Guimarães, Fernando S.; Carvalho, Mara N.; Sousa, Thaís L. M.; Menezes, Sara L. S.; Lopes, Agnaldo J.

    2015-01-01

    Background: Complaints of peripheral muscle weakness are quite common in patients with systemic sclerosis (SSc). It is likely that the muscle impairments may reduce the patients' exercise performance, which in turn may decrease their functional capacity and exert a direct impact on their quality of life. Objectives: To assess the peripheral and respiratory muscle strength in individuals with SSc and to investigate their correlation with the 6-min walk distance (6MWD) and quality of life measurements. Moreover, we aimed to characterize their nutritional status, pulmonary function, functional capacity, and quality of life compared to the controls. Method: The present cross-sectional study included 20 patients with SSc and 20 control subjects. All of the participants were subjected to isometric dynamometry, surface electromyography, bioelectrical impedance analysis, pulmonary function testing, and the 6-min walk test. Patients with SSc also responded to the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and the Health Assessment Questionnaire Disability Index (HAQ-DI). Results: The individuals with SSc exhibited a reduction in quadriceps strength (p=0.0001), increased quadriceps fatigability (p=0.034), impaired pulmonary function, and a reduced 6MWD (p=0.0001) compared to the controls. Quadriceps strength was significantly correlated with the 6MWD (Rho=0.719; p=0.0004) and the HAQ-DI (Rho=-0.622; p=0.003). We also found significant correlations between quadriceps fatigability and maximal inspiratory (Rho=0.684; p=0.0009) and maximal expiratory (Rho=0.472; p=0.035) pressure. Conclusions: Patients with SSc exhibited reduced respiratory muscle and quadriceps strength and an increase in its fatigability. In these individuals, there was a relationship between quadriceps strength, functional capacity, and quality of life. PMID:25789555

  12. Thigh Muscle Strength in Senior Athletes and Healthy Controls

    PubMed Central

    McCrory, Jean L; Salacinski, Amanda J; Hunt, Sarah E; Greenspan, Susan L

    2016-01-01

    Exercise is commonly recommended to counteract aging-related muscle weakness. While numerous exercise intervention studies on the elderly have been performed, few have included elite senior athletes, such as those who participate in the National Senior Games. The extent to which participation in highly competitive exercise affects muscle strength is unknown, as well as the extent to which such participation mitigates any aging-related strength losses. The purpose of this study was to examine isometric thigh muscle strength in selected athletes of the National Senior Games and healthy noncompetitive controls of similar age, as well as to investigate strength changes with aging in both groups. In all, 95 athletes of the Games and 72 healthy controls participated. Of the senior athletes, 43 were runners, 12 cyclists, and 40 swimmers. Three trials of isometric knee flexion and extension strength were collected using a load cell affixed to a custom-designed chair. Strength data were normalized to dual-energy x-ray absorptiometry-obtained lean mass of the leg. A 3-factor multivariate analysis of variance (group × gender × age group) was performed, which included both the extension and flexion variables ([alpha] = 0.05). Athletes exhibited 38% more extension strength and 66% more flexion strength than the controls (p < 0.001). Strength did not decrease with advancing age in either the athletes or the controls (p = 0.345). In conclusion, senior athletes who participate in highly competitive exercise have greater strength than healthy aged-matched individuals who do not. Neither group displayed the expected strength losses with aging. Our subject cohorts, however, were not typical of those over age 65 years because individuals with existing health conditions were excluded from the study. PMID:19972628

  13. Muscle strength and endurance following lowerlimb suspension in man

    NASA Technical Reports Server (NTRS)

    Tesch, Per A.; Berg, Hans E.; Haggmark, Tom; Ohlsen, Hans; Dudley, Gary A.

    1991-01-01

    The effect of lower-limb suspension on the muscle strength and muscle endurance was investigated in six men subjected to four weeks of unilateral unloading of a lower limb (using of a harness attached to a modified shoe), followed by seven weeks of weight-bearing recovery. Results showed a decrease in the cross-sectional area (CSA) of the thigh muscle and in the average peak torque (APT) during three bouts of 30 concentric knee extensions. While the the thigh muscle CSA returned to normal after seven weeks of recovery, the APT recovery was still reduced by 11 percent, suggesting that muscle metabolic function was severely affected by unloading and was not restored by ambulation.

  14. Reference Range of Respiratory Muscle Strength and Its Clinical Application in Amyotrophic Lateral Sclerosis: A Single-Center Study

    PubMed Central

    Park, Kee Hong; Kim, Rock Bum; Yang, Jiwon; Oh, Jung-Hwan; Park, Su-Yeon; Kim, Dong-Gun; Shin, Je-Young

    2016-01-01

    Background and Purpose Evaluating respiratory function is important in neuromuscular diseases. This study explored the reference ranges of the maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP) in healthy adults, and applied them to amyotrophic lateral sclerosis (ALS) patients. Methods MIP, MEP, and SNIP were measured in 67 healthy volunteers aged from 21 to 82 years. Reference ranges were evaluated by multivariate regression analysis using the generalized additive modeling of location, scale, and shape method. Thirty-six ALS patients were reviewed retrospectively, and abnormal values of MIP, MEP, and SNIP were determined according to the reference ranges. Results MIP, MEP, and SNIP were abnormal in 57.1%, 51.4%, and 25.7% of the ALS patients, respectively. MIP and SNIP were significantly correlated with the degree of restrictive pattern and respiratory symptoms. The ALS Functional Rating Scale-Revised score was correlated with SNIP. Conclusions This study has provided the reference range of respiratory muscle strength in healthy adults. This range is suitable for evaluating respiratory function in ALS patients. PMID:27449914

  15. Assessment of respiratory muscle strength in children according to the classification of body mass index

    PubMed Central

    da Rosa, George Jung; Schivinski, Camila Isabel S.

    2014-01-01

    OBJECTIVE: To assess and compare the respiratory muscle strength among eutrophic, overweight and obese school children, as well as to identify anthropometric and respiratory variables related to the results. METHODS: Cross-sectional survey with healthy schoolchildren aged 7-9 years old, divided into three groups: Normal weight, Overweight and Obese. The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was applied. The body mass index (BMI) was evaluated, as well as the forced expiratory volume in one second (FEV1) with a portable digital device. The maximal inspiratory and expiratory pressures (MIP and MEP) were measured by a digital manometer. Comparisons between the groups were made by Kruskal-Wallis test. Spearman's correlation coefficient was used to analyze the correlations among the variables. RESULTS: MIP of eutrophic school children was higher than MIP found in overweight (p=0.043) and obese (p=0.013) children. MIP was correlated with BMI percentile and weight classification (r=-0.214 and r=-0.256) and MEP was correlated with height (r=0.328). Both pressures showed strong correlation with each other in all analyses (r≥0.773), and less correlation with FEV1 (MIP - r=0.362 and MEP - r=0.494). FEV1 correlated with MEP in all groups (r: 0.429 - 0.569) and with MIP in Obese Group (r=0.565). Age was correlated with FEV1 (r=0.578), MIP (r=0.281) and MEP (r=0.328). CONCLUSIONS: Overweight and obese children showed lower MIP values, compared to eutrophic ones. The findings point to the influence of anthropometric variables on respiratory muscle strength in children. PMID:25119758

  16. Daily acute intermittent hypoxia elicits functional recovery of diaphragm and inspiratory intercostal muscle activity after acute cervical spinal injury

    PubMed Central

    Navarrete-Opazo, A.; Vinit, S; Dougherty, B.J.; Mitchell, G.S.

    2015-01-01

    A major cause of mortality after spinal cord injury is respiratory failure. In normal rats, acute intermittent hypoxia (AIH) induces respiratory motor plasticity, expressed as diaphragm (Dia) and second external intercostal (T2 EIC) long-term facilitation (LTF). Dia (not T2 EIC) LTF is enhanced by systemic adenosine 2A (A2a) receptor inhibition in normal rats. We investigated the respective contributions of Dia and T2 EIC to daily AIH-induced functional recovery of breathing capacity with/without A2a receptor antagonist (KW6002, i.p.) following C2 hemisection (C2HS). Rats received daily AIH (dAIH: 10, 5-min episodes, 10.5% O2; 5-min normoxic intervals; 7 successive days beginning 7 days post-C2HS) or daily normoxia (dNx) with/without KW6002, followed by weekly (reminder) presentations for 8 weeks. Ventilation and EMGs from bilateral diaphragm and T2 EIC muscles were measured with room air breathing (21% O2) and maximum chemoreceptor stimulation (MCS: 7% CO2, 10.5% O2). dAIH increased tidal volume (Vt) in C2HS rats breathing room air (dAIH + vehicle: 0.47 ± 0.02, dNx + vehicle: 0.40 ± 0.01ml/100 g; p<0.05) and MCS (dAIH + vehicle: 0.83 ± 0.01, dNx + vehicle: 0.73 ± 0.01ml/100g; p<0.001); KW6002 had no significant effect. dAIH enhanced contralateral (uninjured) diaphragm EMG activity, an effect attenuated by KW6002, during room air breathing and MCS (p<0.05). Although dAIH enhanced contralateral T2 EIC EMG activity during room air breathing, KW6002 had no effect. dAIH had no statistically significant effects on diaphragm or T2 EIC EMG activity ipsilateral to injury. Thus, two weeks post-C2HS: 1) dAIH enhances breathing capacity by effects on contralateral diaphragm and T2 EIC activity; and 2) dAIH-induced recovery is A2a dependent in diaphragm, but not T2 EIC. Daily AIH may be a useful in promoting functional recovery of breathing capacity after cervical spinal injury, but A2a receptor antagonists (eg. caffeine) may undermine its effectiveness shortly after

  17. Age at spinal cord injury determines muscle strength

    PubMed Central

    Thomas, Christine K.; Grumbles, Robert M.

    2014-01-01

    As individuals with spinal cord injury (SCI) age they report noticeable deficits in muscle strength, endurance and functional capacity when performing everyday tasks. These changes begin at ~45 years. Here we present a cross-sectional analysis of paralyzed thenar muscle and motor unit contractile properties in two datasets obtained from different subjects who sustained a cervical SCI at different ages (≤46 years) in relation to data from uninjured age-matched individuals. First, completely paralyzed thenar muscles were weaker when C6 SCI occurred at an older age. Muscles were also significantly weaker if the injury was closer to the thenar motor pools (C6 vs. C4). More muscles were strong (>50% uninjured) in those injured at a younger (≤25 years) vs. young age (>25 years), irrespective of SCI level. There was a reduction in motor unit numbers in all muscles tested. In each C6 SCI, only ~30 units survived vs. 144 units in uninjured subjects. Since intact axons only sprout 4–6 fold, the limits for muscle reinnervation have largely been met in these young individuals. Thus, any further reduction in motor unit numbers with time after these injuries will likely result in chronic denervation, and may explain the late-onset muscle weakness routinely described by people with SCI. In a second dataset, paralyzed thenar motor units were more fatigable than uninjured units. This gap widened with age and will reduce functional reserve. Force declines were not due to electromyographic decrements in either group so the site of failure was beyond excitation of the muscle membrane. Together, these results suggest that age at SCI is an important determinant of long-term muscle strength, and fatigability, both of which influence functional capacity. PMID:24478643

  18. Myotonometry as a Surrogate Measure of Muscle Strength

    NASA Technical Reports Server (NTRS)

    Ang, B. S.; Feeback, D. L.; Leonard, C. T.; Sykes, J.; Kruger, E.; Clarke, M. S. F.

    2007-01-01

    Space flight-induced muscle atrophy/neuromuscular degradation and the consequent decrements in crew-member performance are of increasing concern as mission duration lengthens, and planetary exploration after extended space flight is planned. Pre- to post-flight strength measures have demonstrated that specific countermeasures, such as resistive exercise, are effective at countering microgravity-induced muscle atrophy and preventing decrements in muscle strength. However, in-flight assessment/monitoring of exercise countermeasure effectiveness will be essential during exploration class missions due to their duration. The ability to modify an exercise countermeasure prescription based on such real-time information will allow each individual crew member to perform the optimal amount and type of exercise countermeasure to maintain performance. In addition, such measures can be used to determine if a crew member is physically capable of performing a particular mission-related task during exploration class missions. The challenges faced in acquiring such data are those common to all space operations, namely the requirement for light-weight, low power, mechanically reliable technologies that make valid measurements in microgravity, in this case of muscle strength/neuromuscular function. Here we describe a simple, light-weight, low power, non-invasive device, known as the Myotonometer, that measures tissue stiffness as an indirect measure of muscle contractile state and muscle force production. Repeat myotonometer measurements made at the same location on the surface of the rectis femoris muscle (as determined using a 3D locator device, SEM plus or minus 0.34 mm) were shown to be reproducible over time at both maximal voluntary contraction (MVC) and at rest in a total of 17 sedentary subjects assessed three times over a period of seven days. In addition, graded voluntary isometric force production (i.e. 20%, 40%, 60%, 80% & 100% of MVC) during knee extension was shown to

  19. Levator plate upward lift and levator muscle strength

    PubMed Central

    Rostaminia, Ghazaleh; Peck, Jennifer; Quiroz, Lieschen; Shobeiri, S. Abbas

    2016-01-01

    Objective The aim of study was to compare digital palpation with the levator plate lift measured by endovaginal and transperineal dynamic ultrasound. Methods Dynamic transperineal and endovaginal ultrasound were performed as part of multicompartmental pelvic floor functional assessment. Patients were instructed to perform Kegels while a probe captured the video clip of the levator plate movement at rest and during contraction in 2D mid-sagittal posterior view. We measured the distance between the levator plate and the probe on endovaginal ultrasound as well as the distance between the levator plate and the gothic arch of the pubis in transperineal ultrasound. The change in diameter (lift) and a levator plate lift ratio (lift / rest) x 100) were calculated. Pelvic floor muscle strength was assessed by digital palpation and divided into functional and non-functional groups using the Modified Oxford Scale (MOS). Mean differences in levator plate upward lifts were compared by MOS score using student t-tests and analysis of variance (ANOVA). Results 74 women were available for analysis. The mean age was 55 (SD±11.9). When measured by vaginal dynamic ultrasound, mean values of the lift and lift/rest ratio increased with increasing MOS score (ANOVA p=0.09 and p=0.04, respectively). When MOS scores were categorized to represent non-functional (MOS 0-1) and functional (MOS 2-5) muscle strength groups, the mean values of the lift (3.2 mm vs. 4.6 mm, p=0.03) and lift/rest ratio (13% vs 20%, p=0.01) were significantly higher in women with functional muscle strength. All patients with ≥ 30% lift detected by vaginal ultrasound had functional muscle strength. Conclusions Greater levator plate lift ratio detected by dynamic endovaginal ultrasound was associated with higher muscle strength as determined by MOS. This novel measurement can be incorporated into ultrasound evaluation of the levator ani function. PMID:26333568

  20. Effect of expiratory muscle strength training on elderly cough function.

    PubMed

    Kim, Jaeock; Davenport, Paul; Sapienza, Christine

    2009-01-01

    Age-related loss of muscle strength, known as sarcopenia, in the expiratory muscles, along with reductions in lung elastic recoil and chest wall compliance decreases the intrathoacic airway pressure as well as expiratory flow rates and velocity, greatly impacting an elderly person's ability to generate the forces essential for cough. This study examined the effects of a 4-week expiratory muscle strength training (EMST) program on maximum expiratory pressure (MEP) and cough function in 18 healthy but sedentary elderly adults. MEP significantly increased after the EMST program from 77.14+/-20.20 to 110.83+/-26.11cmH(2)O. Parameters measured during reflexive coughs produced by capsaicin challenge, indicated that compression phase duration significantly decreased (from 0.35+/-0.19 to 0.16+/-0.17s), peak expiratory flow rate decreased (from 4.98+/-2.18 to 8.00+/-3.05l/s) and post-peak plateau integral amplitude significantly increased (from 3.49+/-2.46 to 6.83+/-4.16l/ss) with the EMST program. EMST seems to be an effective program to increase the expiratory muscle strength in the sedentary elderly, which contribute to an enhanced cough function. PMID:18457885

  1. Kinesthetic imagery training of forceful muscle contractions increases brain signal and muscle strength.

    PubMed

    Yao, Wan X; Ranganathan, Vinoth K; Allexandre, Didier; Siemionow, Vlodek; Yue, Guang H

    2013-01-01

    The purpose of this study was to compare the effect of training using internal imagery (IMI; also known as kinesthetic imagery or first person imagery) with that of external imagery (EMI; also known as third-person visual imagery) of strong muscle contractions on voluntary muscle strengthening. Eighteen young, healthy subjects were randomly assigned to one of three groups (6 in each group): internal motor imagery (IMI), external motor imagery (EMI), or a no-practice control (CTRL) group. Training lasted for 6 weeks (~15 min/day, 5 days/week). The participants' right arm elbow-flexion strength, muscle electrical activity, and movement-related cortical potential (MRCP) were evaluated before and after training. Only the IMI group showed significant strength gained (10.8%) while the EMI (4.8%) and CTRL (-3.3%) groups did not. Only the IMI group showed a significant elevation in MRCP on scalp locations over both the primary motor (M1) and supplementary motor cortices (EMI group over M1 only) and this increase was significantly greater than that of EMI and CTRL groups. These results suggest that training by IMI of forceful muscle contractions was effective in improving voluntary muscle strength without physical exercise. We suggest that the IMI training likely strengthened brain-to-muscle (BTM) command that may have improved motor unit recruitment and activation, and led to greater muscle output. Training by IMI of forceful muscle contractions may change the activity level of cortical motor control network, which may translate into greater descending command to the target muscle and increase its strength. PMID:24133427

  2. Correlation between muscle electrophysiology and strength after fibular nerve injury.

    PubMed

    Won, Yu Hui; Kim, Kang-Won; Choi, Jun Tak; Ko, Myoung-Hwan; Park, Sung-Hee; Seo, Jeong-Hwan

    2016-08-01

    Muscle strength measurement is important when evaluating the degree of impairment in patients with nerve injury. However, accurate and objective evaluation may be difficult in patients with severe pain or those who intentionally try to avoid full exertion. We investigated the usefulness of the affected-to-unaffected side electrophysiological parameter ratios as a measure of objective ankle dorsiflexion (ADF) strength in patients with unilateral fibular nerve injury (FNI). ADF strength was measured in patients with FNI via handheld dynamometer and manual muscle test (MMT). Fibular nerve compound muscle action potential (CMAP) amplitude and latency and ADF strength of the affected side were presented as ratios to the corresponding measurements of the unaffected side. We analysed the correlation of the CMAP ratio with the ADF strength ratio using a dynamometer and compared the CMAP ratios according to MMT grade. Fifty-two patients with FNI were enrolled. The mean CMAP latency ratio did not differ between MMT groups (p = 0.573). The CMAP amplitude ratio proportionally increased with the quantified ADF strength ratio via dynamometer increase (ρ = 0.790; p < 0.001), but the CMAP latency ratio and the quantified ADF strength ratio did not significantly correlate (ρ = 0.052; p = 0.713). The average CMAP amplitude ratio significantly differed between MMT groups (p < 0.001), and post hoc tests showed significant differences in all paired comparisons except of Fair and Good grades (p = 0.064). Electrophysiological parameter ratio, such as the affected-to-unaffected side CMAP amplitude ratio, might be sensitive parameters for ADF power estimation after FNI. PMID:27142447

  3. Bone mineral density, muscle strength, and recreational exercise in men

    NASA Technical Reports Server (NTRS)

    Snow-Harter, C.; Whalen, R.; Myburgh, K.; Arnaud, S.; Marcus, R.

    1992-01-01

    Muscle strength has been shown to predict bone mineral density (BMD) in women. We examined this relationship in 50 healthy men who ranged in age from 28 to 51 years (average 38.3 years). BMD of the lumbar spine, proximal femur, whole body, and tibia were measured by dual-energy x-ray absorptiometry (Hologic QDR 1000W). Dynamic strength using one repetition maximum was assessed for the biceps, quadriceps, and back extensors and for the hip abductors, adductors, and flexors. Isometric grip strength was measured by dynamometry. Daily walking mileage was assessed by 9 week stepmeter records and kinematic analysis of video filming. Subjects were designated as exercisers and nonexercisers. Exercisers participated in recreational exercise at least two times each week. The results demonstrated that BMD at all sites correlated with back and biceps strength (p < 0.01 to p = 0.0001). Body weight correlated with tibia and whole-body BMD (p < 0.001); age negatively correlated with Ward's triangle BMD (p < 0.01). In stepwise multiple regressions, back strength was the only independent predictor of spine and femoral neck density (R2 = 0.27). Further, back strength was the most robust predictor of BMD at the trochanter, Ward's triangle, whole body, and tibia, although biceps strength, age, body weight, and leg strength contributed significantly to BMD at these skeletal sites, accounting for 35-52% of the variance in BMD. Exercisers and nonexercisers were similar for walking (3.97 versus 3.94 miles/day), age (37.8 versus 38.5) years, and weight (80.0 versus 77.7 kg). However, BMD and muscle strength were significantly greater in exercises than in nonexercisers.(ABSTRACT TRUNCATED AT 250 WORDS).

  4. Muscle Strength and Flexibility without and with Visual Impairments Judoka's

    ERIC Educational Resources Information Center

    Karakoc, Onder

    2016-01-01

    The aim of this study was to examine muscle strength and flexibility of judoka with and without visual impairments. A total of 32 male national judoka volunteered to participate in this study. There were 20 male judoka without visual impairments (mean ± SD; age: 19.20 ± 5.76 years, body weight: 66.45 ± 11.09 kg, height: 169.60 ± 7.98 cm, sport…

  5. Effects of whole-body vibration after eccentric exercise on muscle soreness and muscle strength recovery

    PubMed Central

    Timon, Rafael; Tejero, Javier; Brazo-Sayavera, Javier; Crespo, Carmen; Olcina, Guillermo

    2016-01-01

    [Purpose] The aim of this study was to investigate whether or not a single whole-body vibration treatment after eccentric exercise can reduce muscle soreness and enhance muscle recovery. [Subjects and Methods] Twenty untrained participants were randomly assigned to two groups: a vibration group (n=10) and control group (n=10). Participants performed eccentric quadriceps training of 4 sets of 5 repetitions at 120% 1RM, with 4 min rest between sets. After that, the vibration group received 3 sets of 1 min whole body vibration (12 Hz, 4 mm) with 30 s of passive recovery between sets. Serum creatine kinase, blood urea nitrogen, muscle soreness (visual analog scale) and muscle strength (peak isometric torque) were assessed. [Results] Creatine kinase was lower in the vibration group than in the control group at 24 h (200.2 ± 8.2 vs. 300.5 ± 26.1 U/L) and at 48 h (175.2 ± 12.5 vs. 285.2 ± 19.7 U/L) post-exercise. Muscle soreness decreased in vibration group compared to control group at 48 h post-exercise (34.1 ± 11.4 vs. 65.2 ± 13.2 mm). [Conclusion] Single whole-body vibration treatment after eccentric exercise reduced delayed onset muscle soreness but it did not affect muscle strength recovery. PMID:27390415

  6. Effects of whole-body vibration after eccentric exercise on muscle soreness and muscle strength recovery.

    PubMed

    Timon, Rafael; Tejero, Javier; Brazo-Sayavera, Javier; Crespo, Carmen; Olcina, Guillermo

    2016-06-01

    [Purpose] The aim of this study was to investigate whether or not a single whole-body vibration treatment after eccentric exercise can reduce muscle soreness and enhance muscle recovery. [Subjects and Methods] Twenty untrained participants were randomly assigned to two groups: a vibration group (n=10) and control group (n=10). Participants performed eccentric quadriceps training of 4 sets of 5 repetitions at 120% 1RM, with 4 min rest between sets. After that, the vibration group received 3 sets of 1 min whole body vibration (12 Hz, 4 mm) with 30 s of passive recovery between sets. Serum creatine kinase, blood urea nitrogen, muscle soreness (visual analog scale) and muscle strength (peak isometric torque) were assessed. [Results] Creatine kinase was lower in the vibration group than in the control group at 24 h (200.2 ± 8.2 vs. 300.5 ± 26.1 U/L) and at 48 h (175.2 ± 12.5 vs. 285.2 ± 19.7 U/L) post-exercise. Muscle soreness decreased in vibration group compared to control group at 48 h post-exercise (34.1 ± 11.4 vs. 65.2 ± 13.2 mm). [Conclusion] Single whole-body vibration treatment after eccentric exercise reduced delayed onset muscle soreness but it did not affect muscle strength recovery. PMID:27390415

  7. Measurements of muscle strength and performance in children with normal and diseased muscle.

    PubMed Central

    Hosking, J P; Bhat, U S; Dubowitz, V; Edwards, R H

    1976-01-01

    A study has been made of two simple means of measuring muscle power in children with normal and diseased muscle. In one the length of time that the leg and the head could be held at 45 degrees above the horizontal was measured with the child supine. In the second, measurements were made of the isometric strength of six muscle groups with the newly developed Hammersmith Myometer. In the timed performance tests only 5 (8%) of a group of 61 children known to have muscle disease achieved the minimum expected values for their ages. Myometer readings of the isometric power of the children with muscle disease also have values which were below those of a comparable group of normal children. The reproducibility of muscle strength measurements in young children has been shown to be good, whereas the timed performance tests, though able to differentiate normal children from children with muscle disease, did not show sufficient reporducibility for this test to be recommended for sequential measurements. Images FIG. 1 PMID:1015849

  8. A comparison of respiratory and peripheral muscle strength, functional exercise capacity, activities of daily living and physical fitness in patients with cystic fibrosis and healthy subjects.

    PubMed

    Arikan, Hulya; Yatar, İlker; Calik-Kutukcu, Ebru; Aribas, Zeynep; Saglam, Melda; Vardar-Yagli, Naciye; Savci, Sema; Inal-Ince, Deniz; Ozcelik, Ugur; Kiper, Nural

    2015-01-01

    There are limited reports that compare muscle strength, functional exercise capacity, activities of daily living (ADL) and parameters of physical fitness of cystic fibrosis (CF) patients with healthy peers in the literature. The purpose of this study was to assess and compare respiratory and peripheral muscle strength, functional exercise capacity, ADL and physical fitness in patients with CF and healthy subjects. Nineteen patients with CF (mean forced expiratory volume in one second-FEV1: 86.56±18.36%) and 20 healthy subjects were included in this study. Respiratory (maximal inspiratory pressure-MIP and maximal expiratory pressure-MEP) and peripheral muscle strength (quadriceps, shoulder abductors and hand grip strength) were evaluated. Functional exercise capacity was determined with 6min walk test (6MWT). ADL was assessed with Glittre ADL test and physical fitness was assessed with Munich fitness test (MFT). There were not any statistically significant difference in MIP, %MIP, MEP and %MEP values between two groups (p>0.05). %Peripheral muscle strength (% quadriceps and shoulder abductors strength), 6MWT distance and %6MWT distance were significantly lower in patients with CF than those of healthy subjects (p<0.05). Glittre ADL-test time was significantly longer in patients with CF than healthy subjects (p<0.05). According to Munich fitness test, the number of bouncing a ball, hanging score, distance of standing vertical jumping and standing vertical jumping score were significantly lower in patients with CF than those of healthy subjects (p<0.05). Peripheral muscle strength, functional exercise capacity, ADL performance and speed, coordination, endurance and power components of physical fitness are adversely affected in mild-severe patients with CF compared to healthy peers. Evaluations must be done in comprehensive manner in patients with CF with all stages. PMID:26241869

  9. Prevalence of reduced muscle strength in older U.S. adults: United States, 2011-2012.

    PubMed

    Looker, Anne C; Wang, Chia-Yih

    2015-01-01

    Five percent of adults aged 60 and over had weak muscle strength and 13% had intermediate muscle strength, as defined by the new FNIH criteria. Weak muscle strength is clinically relevant because it is associated with slow gait speed, an important mobility impairment. It is also linked to an increased risk of death. The prevalence of reduced muscle strength increased with age and was higher in non-Hispanic Asian and Hispanic persons than in non-Hispanic white or non-Hispanic black persons. Decreasing muscle strength was linked with increased difficulty in rising from an armless chair, which is another important type of mobility impairment. PMID:25633238

  10. Associations of Sarcopenia and Sarcopenic Obesity With Metabolic Syndrome Considering Both Muscle Mass and Muscle Strength

    PubMed Central

    2016-01-01

    Objectives: We investigated the associations of sarcopenia-defined both in terms of muscle mass and muscle strength-and sarcopenic obesity with metabolic syndrome. Methods: Secondary data pertaining to 309 subjects (85 men and 224 women) were collected from participants in exercise programs at a health center in a suburban area. Muscle mass was measured using bioelectrical impedance analysis, and muscle strength was measured via handgrip strength. Sarcopenia based on muscle mass alone was defined as a weight-adjusted skeletal muscle mass index more than two standard deviations below the mean of a sex-specific young reference group (class II sarcopenia). Two cut-off values for low handgrip strength were used: the first criteria were <26 kg for men and <18 kg for women, and the second criteria were the lowest quintile of handgrip strength among the study subjects. Sarcopenic obesity was defined as the combination of class II sarcopenia and being in the two highest quintiles of total body fat percentage among the subjects. The associations of sarcopenia and sarcopenic obesity with metabolic syndrome were evaluated using logistic regression models. Results: The age-adjusted risk ratios (RRs) of metabolic syndrome being compared in people with or without sarcopenia defined in terms of muscle mass were 1.25 (95% confidence interval [CI], 1.06 to 1.47, p=0.008) in men and 1.12 (95% CI, 1.06 to 1.19, p<0.001) in women, which were found to be statistically significant relationships. The RRs of metabolic syndrome being compared in people with or without sarcopenic obesity were 1.31 in men (95% CI, 1.10 to 1.56, p=0.003) and 1.17 in women (95% CI, 1.10 to 1.25, p<0.001), which were likewise found to be statistically significant relationships. Conclusions: The associations of sarcopenia defined in terms of muscle mass and sarcopenic obesity with metabolic syndrome were statistically significant in both men and women. Therefore, sarcopenia and sarcopenic obesity must be

  11. Vitamin D and skeletal muscle strength and endurance in COPD.

    PubMed

    Jackson, Abigail S; Shrikrishna, Dinesh; Kelly, Julia L; Kemp, Samuel V; Hart, Nicholas; Moxham, John; Polkey, Michael I; Kemp, Paul; Hopkinson, Nicholas S

    2013-02-01

    It is not known whether vitamin D levels make a significant contribution to muscle dysfunction in chronic obstructive pulmonary disease (COPD). In 104 COPD patients (mean±sd forced expiratory volume in 1 s 44±22 % predicted) and 100 age- and sex-matched controls, serum 25-hydroxyvitamin D (25(OH)D), 1,25-dihydroxyvitamin D (1,25(OH)(2)D) and parathyroid hormone (PTH) levels were measured and related to quadriceps strength and endurance. In a subset of 26 patients and 13 controls, quadriceps biopsy was performed and mRNA expression of myogenic regulatory factors (mrf) and fibre-specific myosin heavy chains (MHC) was determined. COPD patients were weaker and less physically active than controls. 25(OH)D levels were similar in both groups (48.5±25.5 nmol·L(-1) COPD versus 55.4±28.3 nmol·L(-1) control, p=0.07) but PTH levels were significantly higher in patients (5.2±2.3 pmol·mL(-1) versus 4.4±2.0 pmol·L(-1), p=0.01). 1,25(OH)D was significantly correlated with strength in controls, but not in COPD patients and not with quadriceps endurance assessed using repetitive magnetic stimulation in COPD (n=35) or control (n=35) subjects. In controls, but not COPD patients, muscle biopsy analysis showed a negative relationship between 25(OH)D and MHCIIa expression (r(2)=0.5, p=0.01) and a positive relationship between mrf4 and MHCIIa expression (r(2)=0.5, p=0.009), and myogenic regulatory factor myf5 and MHCI expression (r(2)=0.72, p=0.004). In contrast with healthy controls, muscle strength is not associated with vitamin D levels in COPD, which may represent vitamin D resistance. PMID:22556020

  12. The impact of obesity on skeletal muscle strength and structure through adolescence to old age.

    PubMed

    Tomlinson, D J; Erskine, R M; Morse, C I; Winwood, K; Onambélé-Pearson, Gladys

    2016-06-01

    Obesity is associated with functional limitations in muscle performance and increased likelihood of developing a functional disability such as mobility, strength, postural and dynamic balance limitations. The consensus is that obese individuals, regardless of age, have a greater absolute maximum muscle strength compared to non-obese persons, suggesting that increased adiposity acts as a chronic overload stimulus on the antigravity muscles (e.g., quadriceps and calf), thus increasing muscle size and strength. However, when maximum muscular strength is normalised to body mass, obese individuals appear weaker. This relative weakness may be caused by reduced mobility, neural adaptations and changes in muscle morphology. Discrepancies in the literature remain for maximal strength normalised to muscle mass (muscle quality) and can potentially be explained through accounting for the measurement protocol contributing to muscle strength capacity that need to be explored in more depth such as antagonist muscle co-activation, muscle architecture, a criterion valid measurement of muscle size and an accurate measurement of physical activity levels. Current evidence demonstrating the effect of obesity on muscle quality is limited. These factors not being recorded in some of the existing literature suggest a potential underestimation of muscle force either in terms of absolute force production or relative to muscle mass; thus the true effect of obesity upon skeletal muscle size, structure and function, including any interactions with ageing effects, remains to be elucidated. PMID:26667010

  13. Factors affecting isokinetic muscle strength before and after anterior cruciate ligament reconstruction.

    PubMed

    Yüksel, Halil Yalçin; Erkan, Serkan; Uzun, Macit

    2011-06-01

    The purpose of this study was to evaluate the factors affecting muscle strength of ACL-deficient knees before and after ACL reconstruction. The study included 122 male patients who underwent primary ACL reconstruction with a bone-patellar tendon-bone autograft. Preoperative loss and change in muscle strength in both extensor and flexor muscle groups after ACL reconstruction were calculated separately at 60 degrees/sec and 180 degrees/sec angular velocities. We evaluated the effect of surgical delay on the preoperative deficit and on its change after surgery. Muscle strength change after ACL reconstruction was also evaluated in relation to patient compliance to treatment. The longer the delay of ACL reconstruction the more the muscle strength deficit of flexor and extensor muscles increased. In the ACL deficient knees with high strength deficit, improvement in muscle strength was higher after ACL reconstruction for both muscle groups. When delay of ACL reconstruction was short and the patient was compliant to treatment, flexor muscle strength recovery was early. Shortening the delay to reconstruction had a positive influence on muscle strength after ACL reconstruction when preoperative muscle strength deficit was high. PMID:21846002

  14. Traditional versus functional strength training: effects on muscle strength and power in the elderly.

    PubMed

    Lohne-Seiler, Hilde; Torstveit, Monica K; Anderssen, Sigmund A

    2013-01-01

    The aim was to determine whether strength training with machines vs. functional strength training at 80% of one-repetition maximum improves muscle strength and power among the elderly. Sixty-three subjects (69.9 ± 4.1 yr) were randomized to a high-power strength group (HPSG), a functional strength group (FSG), or a nonrandomized control group (CG). Data were collected using a force platform and linear encoder. The training dose was 2 times/wk, 3 sets × 8 reps, for 11 wk. There were no differences in effect between HPSG and FSG concerning sit-to-stand power, box-lift power, and bench-press maximum force. Leg-press maximum force improved in HPSG (19.8%) and FSG (19.7%) compared with CG (4.3%; p = .026). Bench-press power improved in HPSG (25.1%) compared with FSG (0.5%, p = .02) and CG (2%, p = .04). Except for bench-press power there were no differences in the effect of the training interventions on functional power and maximal body strength. PMID:22832419

  15. Influence of noninvasive ventilation by BiPAP on exercise tolerance and respiratory muscle strength in chronic obstructive pulmonary disease patients (COPD).

    PubMed

    Costa, Dirceu; Toledo, Andreza; Silva, Audrey Borghi E; Sampaio, Luciana Maria Malosá

    2006-01-01

    This study aimed to assess the effect of BiPAP, by nasal mask, on exercise tolerance and respiratory muscle strength in patients with a clinical and spirometric diagnosis of moderate/severe COPD (FEV1 < 60% of predicted). Ten patients of 59.4+/-8.9 years old, with FEV1/FVC <70% of predicted level, were treated with 30 minutes of BiPAP (IPAP:10 and 15 cmH2O; EPAP:4 cmH2O), three days per week, during two months. Before and after the treatment, spirometry, inspiratory (MIP) and expiratory (MEP) muscle strength and the distance walked in six minutes (6MWT) were measured. We observed a significant increase (Wilcoxon, p<0.05) in the mean values of MIP (from -55+/-17 to -77+/-19, respectively), MEP (from 75+/-20 to 109+/-36, respectively) and walking distance (from 349+/-67 to 448+/-75). Based on these results, we concluded that BiPAP improves respiratory muscle strength and exercise tolerance in these COPD patients. PMID:16926994

  16. Ankle muscle strength discriminates fallers from non-fallers

    PubMed Central

    Cattagni, Thomas; Scaglioni, Gil; Laroche, Davy; Van Hoecke, Jacques; Gremeaux, Vincent; Martin, Alain

    2014-01-01

    It is well known that center of pressure (CoP) displacement correlates negatively with the maximal isometric torque (MIT) of ankle muscles. This relationship has never been investigated in elderly fallers (EF). The purpose of this study was thus to analyze the relationship between the MIT of ankle muscles and CoP displacement in upright stance in a sample aged between 18 and 90 years old that included EF. The aim was to identify a threshold of torque below which balance is compromised. The MIT of Plantar flexors (PFs) and dorsal flexors (DFs) and CoP were measured in 90 volunteers: 21 healthy young adults (YA) (age: 24.1 ± 5.0), 12 healthy middle-aged adults (MAA) (age: 50.2 ± 4.5), 27 healthy elderly non-fallers (ENF) (age: 75.5 ± 7.0) and 30 EF (age: 78.8 ± 6.7). The MIT of PF and DF were summed to obtain the overall maximal ankle muscle strength. Body weight and height were used to normalize MIT (nMIT) and CoP (nCoP), respectively. nCoP correlated negatively with nMIT. 90% of EF generated an nMIT <3.1 N·m·kg−1, whereas 85% of non-fallers generated an nMIT >3.1 N·m·kg−1. The relationship between nMIT and nCoP implies that ankle muscle weakness contributes to increased postural instability and the risk of falling. We observed that below the threshold of 3.1 N·m·kg−1, postural stability was dramatically diminished and balance was compromised. Our results suggest that measuring ankle torque could be used in routine clinical practice to identify potential fallers. PMID:25566068

  17. Respiratory muscle strength effect on linear and nonlinear heart rate variability parameters in COPD patients

    PubMed Central

    Goulart, Cássia Da Luz; Simon, Julio Cristiano; Schneiders, Paloma De Borba; San Martin, Elisabete Antunes; Cabiddu, Ramona; Borghi-Silva, Audrey; Trimer, Renata; da Silva, Andréa Lúcia Gonçalves

    2016-01-01

    Introduction Chronic obstructive pulmonary disease (COPD) is recognized as a multisystemic inflammatory disease associated with extrapulmonary comorbidities, including respiratory muscle weakness and cardiovascular and cardiac autonomic regulation disorders. We investigated whether alterations in respiratory muscle strength (RMS) would affect cardiac autonomic modulation in COPD patients. Methods This study was a cross-sectional study done in ten COPD patients affected by moderate to very severe disease. The heart rate variability (HRV) signal was recorded using a Polar cardiofrequencimeter at rest in the sitting position (10 minutes) and during a respiratory sinus arrhythmia maneuver (RSA-M; 4 minutes). Linear analysis in the time and frequency domains and nonlinear analysis were performed on the recorded signals. RMS was assessed using a digital manometer, which provided the maximum inspiratory pressure (PImax) and the maximum expiratory pressure (PEmax). Results During the RSA-M, patients presented an HRV power increase in the low-frequency band (LFnu) (46.9±23.7 vs 75.8±27.2; P=0.01) and a decrease in the high-frequency band (HFnu) (52.8±23.5 vs 24.0±27.0; P=0.01) when compared to the resting condition. Significant associations were found between RMS and HRV spectral indices: PImax and LFnu (r=−0.74; P=0.01); PImax and HFnu (r=0.74; P=0.01); PEmax and LFnu (r=−0.66; P=0.01); PEmax and HFnu (r=0.66; P=0.03); between PEmax and sample entropy (r=0.83; P<0.01) and between PEmax and approximate entropy (r=0.74; P=0.01). Using a linear regression model, we found that PImax explained 44% of LFnu behavior during the RSA-M. Conclusion COPD patients with impaired RMS presented altered cardiac autonomic control, characterized by marked sympathetic modulation and a reduced parasympathetic response; reduced HRV complexity was observed during the RSA-M. PMID:27555757

  18. Electrical Muscle Stimulation: An Effective Form of Exercise and Early Mobilization to Preserve Muscle Strength in Critically Ill Patients

    PubMed Central

    Karatzanos, Eleftherios; Gerovasili, Vasiliki; Zervakis, Dimitrios; Tripodaki, Elli-Sophia; Apostolou, Kleovoulos; Vasileiadis, Ioannis; Papadopoulos, Emmanouil; Mitsiou, Georgios; Tsimpouki, Dimitra; Routsi, Christina; Nanas, Serafim

    2012-01-01

    Purpose. This is a secondary analysis of previously published data to investigate the effects of electrical muscle stimulation (EMS) on strength of various muscle groups in critically ill patients. Methods. One hundred forty-two consecutive patients, with APACHE II score ≥ 13, were randomly assigned to the EMS or the control group. EMS sessions were applied daily on vastus lateralis, vastus medialis, and peroneus longus of both lower extremities. Various muscle groups were evaluated with the Medical Research Council (MRC) scale for muscle strength. Handgrip strength assessment was also employed. Results. Twenty four patients in the EMS group and 28 patients in the control group were finally evaluated. EMS patients achieved higher MRC scores than controls (P ≤ 0.05) in wrist flexion, hip flexion, knee extension, and ankle dorsiflexion. Collectively, the EMS group performed higher (P < 0.01) in the legs and overall. Handgrip strength correlated (P ≤ 0.01) with the upper and lower extremities' muscle strength and the overall MRC scores. Conclusions. EMS has beneficial effects on the strength of critically ill patients mainly affecting muscle groups stimulated, while it may also affect muscle groups not involved presenting itself as a potential effective means of muscle strength preservation and early mobilization in this patient population. PMID:22545212

  19. Inspiratory High Frequency Airway Oscillation Attenuates Resistive Loaded Dyspnea and Modulates Respiratory Function in Young Healthy Individuals

    PubMed Central

    Morris, Theresa; Sumners, David Paul; Green, David Andrew

    2014-01-01

    Direct chest-wall percussion can reduce breathlessness in Chronic Obstructive Pulmonary Disease and respiratory function may be improved, in health and disease, by respiratory muscle training (RMT). We tested whether high-frequency airway oscillation (HFAO), a novel form of airflow oscillation generation can modulate induced dyspnoea and respiratory strength and/or patterns following 5 weeks of HFAO training (n = 20) compared to a SHAM-RMT (conventional flow-resistive RMT) device (n = 15) in healthy volunteers (13 males; aged 20–36 yrs). HFAO causes oscillations with peak-to-peak amplitude of 1 cm H2O, whereas the SHAM-RMT device was identical but created no pressure oscillation. Respiratory function, dyspnoea and ventilation during 3 minutes of spontaneous resting ventilation, 1 minute of maximal voluntary hyperventilation and 1 minute breathing against a moderate inspiratory resistance, were compared PRE and POST 5-weeks of training (2×30 breaths at 70% peak flow, 5 days a week). Training significantly reduced NRS dyspnoea scores during resistive loaded ventilation, both in the HFAO (p = 0.003) and SHAM-RMT (p = 0.005) groups. Maximum inspiratory static pressure (cm H2O) was significantly increased by HFAO training (vs. PRE; p<0.001). Maximum inspiratory dynamic pressure was increased by training in both the HFAO (vs. PRE; p<0.001) and SHAM-RMT (vs. PRE; p = 0.021) groups. Peak inspiratory flow rate (L.s−1) achieved during the maximum inspiratory dynamic pressure manoeuvre increased significantly POST (vs. PRE; p = 0.001) in the HFAO group only. HFAO reduced inspiratory resistive loading–induced dyspnoea and augments static and dynamic maximal respiratory manoeuvre performance in excess of flow-resistive IMT (SHAM-RMT) in healthy individuals without the respiratory discomfort associated with RMT. PMID:24651392

  20. Physical activity compensates for increased mortality risk among older people with poor muscle strength.

    PubMed

    Portegijs, E; Rantanen, T; Sipilä, S; Laukkanen, P; Heikkinen, E

    2007-10-01

    The aim of the study was to determine whether habitual physical activity can compensate for the increased mortality risk among older people with poor muscle strength. Mortality was followed up for 10 years after laboratory examination in 558 community dwelling 75- and 80-year-old men and women. Maximal isometric strength of five muscle groups was measured and tertile cut-off points were used to categorize participants. Participants, who reported moderate physical activity for at least 4 h a week, were categorized as physically active and the others as sedentary. High muscle strength and physical activity both protected from mortality, but their effect was not additive. Within each muscle strength tertile, physically active people had a lower mortality risk than sedentary people, the effect being most pronounced among those with lower strength in all muscle groups. A high level of physical activity may thus compensate for the increased mortality associated with low muscle strength. PMID:17166169

  1. Muscle Size Not Density Predicts Variance in Muscle Strength and Neuromuscular Performance in Healthy Adult Men and Women.

    PubMed

    Weeks, Benjamin K; Gerrits, Tom A J; Horan, Sean A; Beck, Belinda R

    2016-06-01

    Weeks, BK, Gerrits, TAJ, Horan, SA, and Beck, BR. Muscle size not density predicts variance in muscle strength and neuromuscular performance in healthy adult men and women. J Strength Cond Res 30(6): 1577-1584, 2016-The purpose of this study was to determine the relationships between peripheral quantitative computed tomography (pQCT)-derived measures of muscle area and density and markers of muscle strength and performance in men and women. Fifty-two apparently healthy adults (26 men, 26 women; age 33.8 ± 12.0 years) volunteered to participate. Dual-energy x-ray absorptiometry (XR-800; Norland Medical Systems, Inc., Trumbull, CT, USA) was used to determine whole body and regional lean and fat tissue mass, whereas pQCT (XCT-3000; Stratec, Pforzheim, Germany) was used to determine muscle cross-sectional area (MCSA) and muscle density of the leg, thigh, and forearm. Ankle plantar flexor and knee extensor strengths were examined using isokinetic dynamometry, and grip strength was examined with dynamometry. Impulse generated during a maximal vertical jump was used as an index of neuromuscular performance. Thigh, forearm, and leg MCSA strongly predicted variance in knee extensor (R = 0.77, p < 0.001) and grip strength (R = 0.77, p < 0.001) and weakly predicted variance in ankle plantar flexor strength (R = 0.20, p < 0.001), respectively, whereas muscle density was only a weak predictor of variance in knee extensor strength (R = 0.18, p < 0.001). Thigh and leg MCSA accounted for 79 and 69% of the variance in impulse generated from a maximal vertical jump (p < 0.001), whereas thigh muscle density predicted only 18% of the variance (p < 0.002). In conclusion, we found that pQCT-derived muscle area is more strongly related to strength and neuromuscular performance than muscle density in adult men and women. PMID:26473521

  2. A NEW CLINICAL MUSCLE FUNCTION TEST FOR ASSESSMENT OF HIP EXTERNAL ROTATION STRENGTH: AUGUSTSSON STRENGTH TEST

    PubMed Central

    2016-01-01

    ABSTRACT Introduction Dynamic clinical tests of hip strength applicable on patients, non–athletes and athletes alike, are lacking. The aim of this study was therefore to develop and evaluate the reliability of a dynamic muscle function test of hip external rotation strength, using a novel device. A second aim was to determine if gender differences exist in absolute and relative hip strength using the new test. Methods Fifty–three healthy sport science students (34 women and 19 men) were tested for hip external rotation strength using a device that consisted of a strap connected in series with an elastic resistance band loop, and a measuring tape connected in parallel with the elastic resistance band. The test was carried out with the subject side lying, positioned in 45 ° of hip flexion and the knees flexed to 90 ° with the device firmly fastened proximally across the knees. The subject then exerted maximal concentric hip external rotation force against the device thereby extending the elastic resistance band. The displacement achieved by the subject was documented by the tape measure and the corresponding force production was calculated. Both right and left hip strength was measured. Fifteen of the subjects were tested on repeated occasions to evaluate test–retest reliability. Results No significant test–retest differences were observed. Intra–class correlation coefficients ranged 0.93–0.94 and coefficients of variation 2.76–4.60%. In absolute values, men were significantly stronger in hip external rotation than women (right side 13.2 vs 11.0 kg, p = 0.001, left side 13.2 vs 11.5 kg, p = 0.002). There were no significant differences in hip external rotation strength normalized for body weight (BW) between men and women (right side 0.17 kg/BW vs 0.17 kg/BW, p = 0.675, left side 0.17 kg/BW vs 0.18 kg/BW, p = 0.156). Conclusions The new muscle function test showed high reliability and thus could be useful for measuring dynamic hip

  3. Effects of Growth Hormone Administration on Muscle Strength in Men over 50 Years Old

    PubMed Central

    Tavares, A. B. W.; Micmacher, E.; Biesek, S.; Assumpção, R.; Redorat, R.; Veloso, U.; Vaisman, M.; Farinatti, P. T. V.; Conceição, F.

    2013-01-01

    Growth hormone (GH) use has been speculated to improve physical capacity in subjects without GH deficiency (GHD) through stimulation of collagen synthesis in the tendon and skeletal muscle, which leads to better exercise training and increased muscle strength. In this context, the use of GH in healthy elderly should be an option for increasing muscle strength. Our aim was to evaluate the effect of GH therapy on muscle strength in healthy men over 50 years old. Fourteen healthy men aged 50–70 years were evaluated at baseline for body composition and muscle strength (evaluated by leg press and bench press exercises, which focus primarily on quadriceps—lower body part and pectoralis major—upper body part—muscles, resp.). Subjects were randomised into 2 groups: GH therapy (7 subjects) and placebo (7 subjects) and reevaluated after 6 months of therapy. Thirteen subjects completed the study (6 subjects in the placebo group and 7 subjects in the GH group). Subjects of both groups were not different at baseline. After 6 months of therapy, muscle strength in the bench press responsive muscles did not increase in both groups and showed a statistically significant increase in the leg press responsive muscles in the GH group. Our study demonstrated an increase in muscle strength in the lower body part after GH therapy in healthy men. This finding must be considered and tested in frail older populations, whose physical incapacity is primarily caused by proximal muscle weakness. The trial was registered with NCT01853566. PMID:24382963

  4. Strength Training for the Intrinsic Flexor Muscles of the Foot: Effects on Muscle Strength, the Foot Arch, and Dynamic Parameters Before and After the Training

    PubMed Central

    Hashimoto, Takayuki; Sakuraba, Keishoku

    2014-01-01

    [Purpose] The purpose of the present study was to verify the effects of intrinsic foot flexor strength training. [Subjects] The subjects were 12 healthy males without motor system disease. [Methods] A training method that involved flexion of all toe interphalangeal and metatarsophalangeal joints against a 3-kg load was implemented and was performed for 200 repetitions once per day, three times per week, for a period of eight weeks. [Results] Significant changes were observed for intrinsic foot flexor strength scores, foot arches, vertical jumping, 1-legged long jumping, and 50-m dash time. [Conclusion] This muscle strength training method significantly improved muscle strength scores, foot arch shape, and movement performance. PMID:24707086

  5. Impact on nutrition on muscle strength and performance in older adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Muscle strength plays an important role in determining risk for falls, which result in fractures and other injuries. While bone loss has long been recognized as an inevitable consequence of aging, sarcopenia-the gradual loss of skeletal muscle mass and strength that occurs with advancing age-has rec...

  6. Impact of nutrition on muscle mass, strength, and performance in older adults.

    PubMed

    Mithal, A; Bonjour, J-P; Boonen, S; Burckhardt, P; Degens, H; El Hajj Fuleihan, G; Josse, R; Lips, P; Morales Torres, J; Rizzoli, R; Yoshimura, N; Wahl, D A; Cooper, C; Dawson-Hughes, B

    2013-05-01

    Muscle strength plays an important role in determining risk for falls, which result in fractures and other injuries. While bone loss has long been recognized as an inevitable consequence of aging, sarcopenia-the gradual loss of skeletal muscle mass and strength that occurs with advancing age-has recently received increased attention. A review of the literature was undertaken to identify nutritional factors that contribute to loss of muscle mass. The role of protein, acid-base balance, vitamin D/calcium, and other minor nutrients like B vitamins was reviewed. Muscle wasting is a multifactorial process involving intrinsic and extrinsic alterations. A loss of fast twitch fibers, glycation of proteins, and insulin resistance may play an important role in the loss of muscle strength and development of sarcopenia. Protein intake plays an integral part in muscle health and an intake of 1.0-1.2 g/kg of body weight per day is probably optimal for older adults. There is a moderate [corrected] relationship between vitamin D status and muscle strength. Chronic ingestion of acid-producing diets appears to have a negative impact on muscle performance, and decreases in vitamin B12 and folic acid intake may also impair muscle function through their action on homocysteine. An adequate nutritional intake and an optimal dietary acid-base balance are important elements of any strategy to preserve muscle mass and strength during aging. PMID:23247327

  7. Serial Changes of Quadriceps and Hamstring Muscle Strength Following Total Knee Arthroplasty: A Meta-Analysis

    PubMed Central

    Ahn, Hyeong-Sik; Lee, Dae-Hee

    2016-01-01

    This meta-analysis was performed to analyze serial changes in thigh muscles, including quadriceps and hamstring muscles, from before to one year after total knee arthroplasty (TKA). All studies sequentially comparing isokinetic quadriceps and hamstring muscle strengths between the TKA side and the contralateral uninjured limb were included in this meta-analysis. Five studies with 7 cohorts were included in this meta-analysis. The mean differences in the strengths of quadriceps and hamstring muscles between the TKA and uninjured sides were greatest three months after surgery (26.8 N∙m, 12.8 N∙m, P<0.001), but were similar to preoperative level at six months (18.4 N∙m, 7.4 N∙m P<0.001) and were maintained for up to one year (15.9 N∙m, 4.1 N∙m P<0.001). The pooled mean differences in changes in quadriceps and hamstring strengths relative to preoperative levels were 9.2 N∙m and 4.9 N∙m, respectively, three months postoperatively (P = 0.041), but were no longer significant after six months and one year. During the year after TKA, quadriceps and hamstring muscle strengths were lowest after 3 months, recovering to preoperative level after six months, but not reaching the muscle strength on the contralateral side. Relative to preoperative levels, the difference in muscle strength between the TKA and contralateral knees was only significant at three months. Because decrease of strength of the quadriceps was significantly greater than decrease in hamstring muscle strength at postoperative three months, early rehabilitation after TKA should focus on recovery of quadriceps muscle strength. PMID:26849808

  8. Relation between systemic inflammatory markers, peripheral muscle mass, and strength in limb muscles in stable COPD patients

    PubMed Central

    Ferrari, Renata; Caram, Laura MO; Faganello, Marcia M; Sanchez, Fernanda F; Tanni, Suzana E; Godoy, Irma

    2015-01-01

    The aim of this study was to investigate the association between systemic inflammatory mediators and peripheral muscle mass and strength in COPD patients. Fifty-five patients (69% male; age: 64±9 years) with mild/very severe COPD (defined as forced expiratory volume in the first second [FEV1] =54%±23%) were evaluated. We evaluated serum concentrations of IL-8, CRP, and TNF-α. Peripheral muscle mass was evaluated by computerized tomography (CT); midthigh cross-sectional muscle area (MTCSA) and midarm cross-sectional muscle area (MACSA) were obtained. Quadriceps, triceps, and biceps strength were assessed through the determination of the one-repetition maximum. The multiple regression results, adjusted for age, sex, and FEV1%, showed positive significant association between MTCSA and leg extension (0.35 [0.16, 0.55]; P=0.001), between MACSA and triceps pulley (0.45 [0.31, 0.58]; P=0.001), and between MACSA and biceps curl (0.34 [0.22, 0.47]; P=0.001). Plasma TNF-α was negatively associated with leg extension (−3.09 [−5.99, −0.18]; P=0.04) and triceps pulley (−1.31 [−2.35, −0.28]; P=0.01), while plasma CRP presented negative association with biceps curl (−0.06 [−0.11, −0.01]; P=0.02). Our results showed negative association between peripheral muscle mass (evaluated by CT) and muscle strength and that systemic inflammation has a negative influence in the strength of specific groups of muscles in individuals with stable COPD. This is the first study showing association between systemic inflammatory markers and strength in upper limb muscles. PMID:26345641

  9. Relationships between Lower Limb Muscle Strength and Locomotor Capacity in Children and Adolescents with Cerebral Palsy Who Walk Independently

    ERIC Educational Resources Information Center

    Ferland, Chantale; Lepage, Celine; Moffet, Helene; Maltais, Desiree B.

    2012-01-01

    This study aimed to quantify relationships between lower limb muscle strength and locomotor capacity for children and adolescents with cerebral palsy (CP) to identify key muscle groups for strength training. Fifty 6- to 16-year-olds with CP (Gross Motor Function Classification System level I or II) participated. Isometric muscle strength of hip…

  10. Measurement of muscle strength with handheld dynamometer in Intensive Care Unit

    PubMed Central

    Samosawala, Nidhi R.; Vaishali, K.; Kalyana, B. Chakravarthy

    2016-01-01

    Background: Intensive Care Unit (ICU) acquired weakness is a common complication in critically ill patients affecting their prognosis. The handheld dynamometry is an objective method in detecting minimum muscle strength change, which has an impact on the physical function of ICU survivors. The minimal change in the force can be measured in units of weight such as pounds or kilograms. Aim of the Study: To detect the changes in peripheral muscle strength with handheld dynamometer in the early stage of ICU stay and to observe the progression of muscle weakness. Methodology: Three upper and three lower limb muscles force measured with handheld dynamometer during ICU stay. Data were analyzed using repeated measures ANOVA to detect changes in force generated by muscle on alternate days of ICU stay. Results: There was a reduction in peripheral muscle strength from day 3 to day 5 as well from day 5 to day 7 of ICU stay (P < 0.01). The average reduction in peripheral muscle strength was 11.8% during ICU stay. Conclusion: This study showed a progressive reduction in peripheral muscle strength as measured by handheld dynamometer during early period of ICU stay. PMID:26955213

  11. Effect of trapezius muscle strength on three-dimensional scapular kinematics

    PubMed Central

    Turgut, Elif; Duzgun, Irem; Baltaci, Gul

    2016-01-01

    [Purpose] This study aimed to investigate the effect of trapezius muscle isometric strength on three-dimensional scapular kinematics in asymptomatic shoulders. [Subjects and Methods] Thirty asymptomatic subjects were included to the study. Isometric strengths of the upper, middle, and lower trapezius muscle were measured using a handheld dynamometer. Three-dimensional scapular kinematics was recorded by an electromagnetic tracking device during frontal and sagittal plane elevation. For each muscle, the cut-off value for muscle strength was determined with the upper bound of the 95% confidence interval, and Student’s t-test was used to compare the scapular kinematics between subjects with relatively weaker or stronger trapezius muscles. [Results] Shoulders with stronger upper trapezius muscles showed greater upward scapular rotation at 30°, 60°, 90°, and 120° of elevation in the frontal plane. Shoulders with stronger middle trapezius had greater scapular upward rotation at 90° of elevation in the frontal plane. Shoulders with stronger lower trapezius showed greater scapular posterior tilt at 90° of elevation in the sagittal plane. [Conclusion] This study’s findings showed that isometric strength of the trapezius muscle affects upward scapular rotation and posterior tilt in asymptomatic shoulders. Therefore, trapezius muscle strength should be assessed and potential weakness should be addressed in shoulder rehabilitation programs. PMID:27390435

  12. Relationship Between Intensity of Quadriceps Muscle Neuromuscular Electrical Stimulation and Strength Recovery After Total Knee Arthroplasty

    PubMed Central

    Balter, Jaclyn E.; Wolfe, Pamela; Eckhoff, Donald G.; Schwartz, Robert S.; Schenkman, Margaret; Kohrt, Wendy M.

    2012-01-01

    Background Neuromuscular electrical stimulation (NMES) can facilitate the recovery of quadriceps muscle strength after total knee arthroplasty (TKA), yet the optimal intensity (dosage) of NMES and its effect on strength after TKA have yet to be determined. Objective The primary objective of this study was to determine whether the intensity of NMES application was related to the recovery of quadriceps muscle strength early after TKA. A secondary objective was to quantify quadriceps muscle fatigue and activation immediately after NMES to guide decisions about the timing of NMES during rehabilitation sessions. Design This study was an observational experimental investigation. Methods Data were collected from 30 people who were 50 to 85 years of age and who received NMES after TKA. These people participated in a randomized controlled trial in which they received either standard rehabilitation or standard rehabilitation plus NMES to the quadriceps muscle to mitigate strength loss. For the NMES intervention group, NMES was applied 2 times per day at the maximal tolerable intensity for 15 contractions beginning 48 hours after surgery over the first 6 weeks after TKA. Neuromuscular electrical stimulation training intensity and quadriceps muscle strength and activation were assessed before surgery and 3.5 and 6.5 weeks after TKA. Results At 3.5 weeks, there was a significant association between NMES training intensity and a change in quadriceps muscle strength (R2=.68) and activation (R2=.22). At 6.5 weeks, NMES training intensity was related to a change in strength (R2=.25) but not to a change in activation (R2=.00). Furthermore, quadriceps muscle fatigue occurred during NMES sessions at 3.5 and 6.5 weeks, whereas quadriceps muscle activation did not change. Limitations Some participants reached the maximal stimulator output during at least 1 treatment session and might have tolerated more stimulation. Conclusions Higher NMES training intensities were associated with

  13. Description of Peripheral Muscle Strength Measurement and Correlates of Muscle Weakness in Patients Receiving Prolonged Mechanical Ventilatory Support

    PubMed Central

    Chlan, Linda L.; Tracy, Mary Fran; Guttormson, Jill; Savik, Kay

    2015-01-01

    Background Intensive Care Unit Acquired Weakness (ICUAW) is a frequent complication of critical illness due to immobility and prolonged mechanical ventilatory support. Objectives To describe daily peripheral muscle strength measurement in ventilated patients and explore relationships among factors that influence ICUAW. Methods Peripheral muscle strength of 120 ventilated ICU patients (mean age 59.8 ± 15.1; 51% female; APACHE III 61.3 ± 20.7; ICU stay 10.6 ± 8.6 days) was measured daily using a standardized hand grip dynamometry protocol. Three grip measurements for each hand were recorded in pounds-force; the mean of these three assessments was used in the analysis. Correlates of ICUAW were analyzed with mixed models to explore their relationship to grip strength (age, gender, illness severity, length of ventilatory support, medications). Results Median baseline grip strength was variable yet diminished (7.7; 0-102) with either a pattern of diminishing grip strength or maintenance of the baseline low grip strength over time. Controlling for days on protocol, female gender [β = −10.4(2.5); p = <.001], age [= −.24(.08); p = .004], and days receiving ventilatory support [= −.34(.12); p = .005] explained a significant amount of variance in grip strength over time. Conclusions Patients receiving prolonged periods of mechanical ventilatory support in this sample show marked decrements in grip strength measured by hand dynamometry, a marker for peripheral muscle strength. Hand dynamometry is a reliable method to measure muscle strength in cooperative ICU patients and can be used in future research to ultimately develop interventions to prevent ICUAW. PMID:26523017

  14. Reduced Neck Muscle Strength and Altered Muscle Mechanical Properties in Cervical Dystonia Following Botulinum Neurotoxin Injections: A Prospective Study

    PubMed Central

    Mustalampi, Sirpa; Ylinen, Jari; Korniloff, Katariina; Weir, Adam; Häkkinen, Arja

    2016-01-01

    Objective To evaluate changes in the strength and mechanical properties of neck muscles and disability in patients with cervical dystonia (CD) during a 12-week period following botulinum neurotoxin (BoNT) injections. Methods Eight patients with CD volunteered for this prospective clinical cohort study. Patients had received BoNT injections regularly in neck muscles at three-month intervals for several years. Maximal isometric neck strength was measured by a dynamometer, and the mechanical properties of the splenius capitis were evaluated using two myotonometers. Clinical assessment was performed using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) before and at 2, 4, 8, and 12 weeks after the BoNT injections. Results Mean maximal isometric neck strength at two weeks after the BoNT injections decreased by 28% in extension, 25% in rotation of the affected side and 17% in flexion. At four weeks, muscle stiffness of the affected side decreased by 17% and tension decreased by 6%. At eight weeks, the muscle elasticity on the affected side increased by 12%. At two weeks after the BoNT injections, the TWSTRS-severity and TWSTRS-total scores decreased by 4.3 and 6.4, respectively. The strength, muscle mechanical properties and TWSTRS scores returned to baseline values at 12 weeks. Conclusions Although maximal neck strength and muscle tone decreased after BoNT injections, the disability improved. The changes observed after BoNT injections were temporary and returned to pre-injection levels within twelve weeks. Despite having a possible negative effect on function and decreasing neck strength, the BoNT injections improved the patients reported disability. PMID:26828215

  15. Protein Intake and Muscle Strength in Older Persons: Does Inflammation Matter?

    PubMed Central

    Bartali, Benedetta; Frongillo, Edward A.; Stipanuk, Martha H.; Bandinelli, Stefania; Salvini, Simonetta; Palli, Domenico; Morais, Jose A.; Volpato, Stefano; Guralnik, Jack M.; Ferrucci, Luigi

    2011-01-01

    BACKGROUND/OBJECTIVES The effect of dietary protein intake on muscle strength in older persons is unknown. The objective of this study was to examine whether protein intake is associated with change in muscle strength in older persons. Because systemic inflammation has been associated with protein catabolism, we also evaluated whethera synergistic effect exists between protein intake and inflammatory markers on change in muscle strength using a longitudinal study of community-dwelling persons aged 65 years or older. DESIGN Longitudinal. SETTING The InCHIANTI Study. PARTICIPANTS Five hundred and ninety-eight persons. MEASUREMENTS Knee extension strength was measured at baseline (1998–2000) and during 3-year follow-up (2001–2003) using a hand-held dynamometer. Protein intake was assessed using a very detailed food frequency questionnaire. The inflammatory markers included in this study were C-reactive protein (CRP), Interleukin-6 (IL-6), and Tumor Necrosis Factor-α (TNF-α). RESULTS The main effect of protein intake on change in muscle strength was not significant, but we found a significant interaction between protein intake and CRP, IL-6 and TNF-α (p=0.003, p=0.049 and p=0.019, respectively), indicating thata lower protein intake was associated with a greater decline in muscle strength in persons with high levels of inflammatory markers. CONCLUSION Selectively in older persons with a pro-inflammatory state, low protein intake was associated with accelerated decline in muscle strength. These results may help to understand the factors contributing to decline in muscle strength and to identify the target population of older persons who may benefit from nutritional interventions aimed at preventing or reducing age-associated muscle impairments and its detrimental consequences. PMID:22283208

  16. The effect of hip joint muscle exercise on muscle strength and balance in the knee joint after meniscal injury.

    PubMed

    Park, Sun Ja; Kim, Young Mi; Kim, Ha Roo

    2016-04-01

    [Purpose] This study aimed to evaluate the effect of hip muscle strengthening on muscle strength and balance in the knee joint after a meniscal injury. [Subjects and Methods] This randomized control study enrolled 24 patients who had undergone arthroscopic treatment after a meniscal injury and began a rehabilitative exercise program 8 weeks after surgery. Subjects were divided into 2 groups of 12 subjects each: gluteus medius resistance exercise group and control group. This study investigated muscle strength and balance in the knee joint flexor, extensor, and abductor during an 8-week period. [Results] Measurements of knee extensor muscle strength revealed no significant difference between the control group and the experimental group. Measurements of abductor muscle strength, however, identified a significant difference between the 2 groups. The groups did not differ significantly with regard to balance measurements. [Conclusion] The results of this study suggest that this subject should be approached in light of the correlation between the hip abductor and injury to the lower extremities. PMID:27190461

  17. The effect of hip joint muscle exercise on muscle strength and balance in the knee joint after meniscal injury

    PubMed Central

    Park, Sun Ja; Kim, Young Mi; Kim, Ha Roo

    2016-01-01

    [Purpose] This study aimed to evaluate the effect of hip muscle strengthening on muscle strength and balance in the knee joint after a meniscal injury. [Subjects and Methods] This randomized control study enrolled 24 patients who had undergone arthroscopic treatment after a meniscal injury and began a rehabilitative exercise program 8 weeks after surgery. Subjects were divided into 2 groups of 12 subjects each: gluteus medius resistance exercise group and control group. This study investigated muscle strength and balance in the knee joint flexor, extensor, and abductor during an 8-week period. [Results] Measurements of knee extensor muscle strength revealed no significant difference between the control group and the experimental group. Measurements of abductor muscle strength, however, identified a significant difference between the 2 groups. The groups did not differ significantly with regard to balance measurements. [Conclusion] The results of this study suggest that this subject should be approached in light of the correlation between the hip abductor and injury to the lower extremities. PMID:27190461

  18. Strength training improves muscle quality and insulin sensitivity in older Hispanics with type 2 diabetes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hispanics have an increased risk of morbidity and mortality due to their high prevalence of diabetes. Body composition, particularly skeletal muscle, plays an important role in glycemic control and lipid metabolism. Strength training is the most effective means to increase muscle mass but limited ...

  19. Changes in the muscle strength and functional performance of healthy women with aging

    PubMed Central

    Mousavikhatir, Roghayeh

    2012-01-01

    Background Lower limbs antigravity muscles weakness and decreased functional ability have significant role in falling. The aim of this study was to find the effects of aging on muscle strength and functional ability, determining the range of decreasing strength and functional ability and relationship between them in healthy women. Methods Across-section study was performed on 101 healthy women aged 21-80 years. The participants were divided into six age groups. The maximum isometric strength of four muscle groups was measured using a hand-held dynamometer bilaterally. The functional ability was measured with functional reach (FR), timed get up and go (TGUG), single leg stance (SLS), and stairs walking (SW) tests. Results Muscle strength changes were not significant between 21-40 years of age, but decreased significantly thereafter. Also, there was a significant relationship between muscle strength and functional ability in age groups. Conclusion Both muscle strength and functional ability is reduced as a result of aging, but the decrease in functional ability can be detected earlier. PMID:23482911

  20. Effect of yoga training and detraining on respiratory muscle strength in pre-pubertal children: A randomized trial

    PubMed Central

    D'Souza, Crystal Dalia; Avadhany, Sandhya T

    2014-01-01

    Objective: To evaluate the effect of yoga on forced vital capacity (FVC), forced expiratory volume in Ist second (FEV1), peak expiratory flow rate (PEFR), FEVI/FVC ratio, and pulmonary pressures [maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP) at the end of 3 months yoga training and the detraining effect on the above parameters in 7-9-years-old school going children. Materials and Methods: A total of 100 participants were recruited from a school in Bangalore. After baseline assessments, the participants were randomly allocated to either yoga or physical activity group. Intervention was given for 3 months, and measures of pulmonary function and pulmonary pressures were determined immediately post-intervention and at 3-months follow-up. Results: Although significant increase was observed in FVC, FEV1, PEFR, FEV1/FVC, MIP, and MEP at post-intervention, there were no significant differences between the two study groups after adjusting for height and age post training . However, MIP increased significantly in both the groups post-intervention, but the yoga group performed significantly higher than the PE group. The effects of training did not fade off even after 3 months of detraining. In fact, the FVC and FEV1 continued to increase significantly. A trend of decrease was observed in PEFR, MIP, and MEP. However, the values did not regress to the baseline value. Conclusions: This study suggests that practice of yoga for a short duration (3 months) of time can significantly improve respiratory muscle strength in pediatric population. PMID:25035606

  1. The effect of strength training on muscle cellular stress in prostate cancer patients on ADT

    PubMed Central

    Thorsen, L; Kirkegaard, C; Ugelstad, I; Fosså, S D; Raastad, T

    2016-01-01

    Background Androgen deprivation therapy (ADT) for prostate cancer (PCa) is associated with several side effects, including loss of muscle mass. Muscle atrophy is associated with reduced mitochondrial function and increased muscle cellular stress that may be counteracted by strength training. Thus, the aim of this study was to investigate the effect of strength training on mitochondrial proteins and indicators of muscle cellular stress in PCa patients on ADT. Methods Men diagnosed with locally advanced PCa receiving ADT were randomised to a strength training group (STG) (n=16) or a control group (CG) (n=15) for 16 weeks. Muscle biopsies were collected pre- and post-intervention from the vastus lateralis muscle, and analysed for mitochondrial proteins (citrate synthase, cytochrome c oxidase subunit IV (COXIV), HSP60) and indicators of muscle cellular stress (heat shock protein (HSP) 70, alpha B-crystallin, HSP27, free ubiquitin, and total ubiquitinated proteins) using Western blot and ELISA. Results No significant intervention effects were observed in any of the mitochondrial proteins or indicators of muscle cellular stress. However, within-group analysis revealed that the level of HSP70 was reduced in the STG and a tendency towards a reduction in citrate synthase levels was observed in the CG. Levels of total ubiquitinated proteins were unchanged in both groups. Conclusion Although reduced HSP70 levels indicated reduced muscle cellular stress in the STG, the lack of an intervention effect precluded any clear conclusions. PMID:27169606

  2. Patterns of expiratory and inspiratory activation for thoracic motoneurones in the anaesthetized and the decerebrate rat

    PubMed Central

    de Almeida, Anoushka T R; Al-Izki, Sarah; Denton, Manuel Enríquez; Kirkwood, Peter A

    2010-01-01

    The nervous control of expiratory muscles is less well understood than that of the inspiratory muscles, particularly in the rat. The patterns of respiratory discharges in adult rats were therefore investigated for the muscles of the caudal intercostal spaces, with hypercapnia and under either anaesthesia or decerebration. With neuromuscular blockade and artificial ventilation, efferent discharges were present for both inspiration and expiration in both external and internal intercostal nerves. This was also the case for proximal internal intercostal nerve branches that innervate only internal intercostal and subcostalis muscles. If active, this region of muscle in other species is always expiratory. Here, inspiratory bursts were almost always present. The expiratory activity appeared only gradually and intermittently, when the anaesthesia was allowed to lighten or as the pre-decerebration anaesthesia wore off. The intermittent appearance is interpreted as the coupling of a slow medullary expiratory oscillator with a faster inspiratory one. The patterns of nerve discharges, in particular the inspiratory or biphasic activation of the internal and subcostalis layers, were confirmed by observations of equivalent patterns of EMG discharges in spontaneously breathing preparations, using denervation procedures to identify which muscles generated the signals. Some motor units were recruited in both inspiratory and expiratory bursts. These patterns of activity have not previously been described and have implications both for the functional role of multiple respiratory oscillators in the adult and for the mechanical actions of the muscles of the caudal intercostal spaces, including subcostalis, which is a partly bisegmental muscle. PMID:20530111

  3. The effects of kinesio taping on architecture, strength and pain of muscles in delayed onset muscle soreness of biceps brachii

    PubMed Central

    Lee, Yong Sin; Bae, Sea Hyun; Hwang, Jin Ah; Kim, Kyung Yoon

    2015-01-01

    [Purpose] This study aimed to confirm the effects of kinesio taping (KT) on muscle function and pain due to delayed onset muscle soreness (DOMS) of the biceps brachii. [Subjects and Methods] Thirty-seven subjects with induced DOMS were randomized into either Group I (control, n=19) or Group II (KT, n=18). Outcome measures were recorded before the intervention (application of KT) and at 24, 48, and 72 hours after the intervention. DOMS was induced, and muscle thickness was measured using ultrasonic radiography. Maximal voluntary isometric contraction (%MVIC) was measured via electromyography (EMG). Subjective pain was measured using a visual analogue scale (VAS). [Results] Group I exhibited a positive correlation between muscle thickness and elapsed time from intervention (24, 48, and 72 hours post induction of DOMS); they also showed a significant decrease in MVIC(%). Group II showed significant increases in muscle thickness up to the 48-hour interval post induction of DOMS, along with a significant decrease in MVIC (%). However, in contrast to Group I, Group II did not show a significant difference in muscle thickness or MVIC (%) at the 72-hour interval in comparison with the values prior to DOMS induction. [Conclusion] In adults with DOMS, activation of muscles by applying KT was found to be an effective and faster method of recovering muscle strength than rest alone. PMID:25729190

  4. The effects of kinesio taping on architecture, strength and pain of muscles in delayed onset muscle soreness of biceps brachii.

    PubMed

    Lee, Yong Sin; Bae, Sea Hyun; Hwang, Jin Ah; Kim, Kyung Yoon

    2015-02-01

    [Purpose] This study aimed to confirm the effects of kinesio taping (KT) on muscle function and pain due to delayed onset muscle soreness (DOMS) of the biceps brachii. [Subjects and Methods] Thirty-seven subjects with induced DOMS were randomized into either Group I (control, n=19) or Group II (KT, n=18). Outcome measures were recorded before the intervention (application of KT) and at 24, 48, and 72 hours after the intervention. DOMS was induced, and muscle thickness was measured using ultrasonic radiography. Maximal voluntary isometric contraction (%MVIC) was measured via electromyography (EMG). Subjective pain was measured using a visual analogue scale (VAS). [Results] Group I exhibited a positive correlation between muscle thickness and elapsed time from intervention (24, 48, and 72 hours post induction of DOMS); they also showed a significant decrease in MVIC(%). Group II showed significant increases in muscle thickness up to the 48-hour interval post induction of DOMS, along with a significant decrease in MVIC (%). However, in contrast to Group I, Group II did not show a significant difference in muscle thickness or MVIC (%) at the 72-hour interval in comparison with the values prior to DOMS induction. [Conclusion] In adults with DOMS, activation of muscles by applying KT was found to be an effective and faster method of recovering muscle strength than rest alone. PMID:25729190

  5. [Use of pulmonary rehabilitation in the treatment of decreased respiratory muscle strength].

    PubMed

    Neumannová, Kateřina

    2015-01-01

    Decreased respiratory muscle strength could lead to other health problems, which can decrease the quality of life of those patients. Ineffective expectoration and dyspnoea during physical activities and during activity of daily living are the most frequent disorders associated with decreased respiratory muscle strength. Multidisciplinary treatment including pulmonary rehabilitation programme is very important for those patients. Ventilatory muscle training (strength and endurance type of training), airway clearance techniques - active (e.g. autogenic drainage, instrumental techniques) and passive (e.g. manual thoracic compression, mechanical insufflator/exsufflator machine) and exercise training are the most frequent used techniques in these patients. Assessment of all respiratory muscles function - especially their respiratory and postural function - is important at the beginning of rehabilitation treatment. PMID:25994909

  6. Shank Muscle Strength Training Changes Foot Behaviour during a Sudden Ankle Supination

    PubMed Central

    Hagen, Marco; Lescher, Stephanie; Gerhardt, Andreas; Lahner, Matthias; Felber, Stephan; Hennig, Ewald M.

    2015-01-01

    Background The peroneal muscles are the most effective lateral stabilisers whose tension braces the ankle joint complex against excessive supination. The purpose of this study was to identify the morphological and biomechanical effects of two machine-based shank muscle training methods. Methods Twenty-two healthy male recreationally active sports students performed ten weeks of single-set high resistance strength training with 3 training sessions per week. The subjects conducted subtalar pronator/supinator muscle training (ST) with the right leg by using a custom-made apparatus; the left foot muscles were exercised with machine-based talocrural plantar and dorsiflexor training (TT). Muscle strength (MVIC), muscle volume and foot biomechanics (rearfoot motion, ground reaction forces, muscle reaction times) during a sudden ankle supination were recorded before and after the intervention. Results Compared to TT, ST resulted in significantly higher pronator (14% vs. 8%, P<0.01) and supinator MVIC (25% vs. 12%, P<0.01). During sudden foot inversions, both ST and TT resulted in reduced supination velocity (-12%; P<0.01). The muscle reaction onset time was faster after the training in peroneus longus (PL) (P<0.01). Muscle volume of PL (P<0.01) and TA (P<0.01) increased significantly after both ST and TT. Conclusion After both ST and TT, the ankle joint complex is mechanically more stabilised against sudden supinations due to the muscle volume increase of PL and TA. As the reduced supination velocities indicate, the strength training effects are already present during free-fall. According to a sudden ankle supination in standing position, both machine-based dorsiflexor and pronator strength training is recommended for enhancing the mechanical stability of the ankle. PMID:26110847

  7. Gene transcripts associated with muscle strength: a CHARGE meta-analysis of 7,781 persons.

    PubMed

    Pilling, L C; Joehanes, R; Kacprowski, T; Peters, M; Jansen, R; Karasik, D; Kiel, D P; Harries, L W; Teumer, A; Powell, J; Levy, D; Lin, H; Lunetta, K; Munson, P; Bandinelli, S; Henley, W; Hernandez, D; Singleton, A; Tanaka, T; van Grootheest, G; Hofman, A; Uitterlinden, A G; Biffar, R; Gläser, S; Homuth, G; Malsch, C; Völker, U; Penninx, B; van Meurs, J B J; Ferrucci, L; Kocher, T; Murabito, J; Melzer, D

    2016-01-01

    Lower muscle strength in midlife predicts disability and mortality in later life. Blood-borne factors, including growth differentiation factor 11 (GDF11), have been linked to muscle regeneration in animal models. We aimed to identify gene transcripts associated with muscle strength in adults. Meta-analysis of whole blood gene expression (overall 17,534 unique genes measured by microarray) and hand-grip strength in four independent cohorts (n = 7,781, ages: 20-104 yr, weighted mean = 56), adjusted for age, sex, height, weight, and leukocyte subtypes. Separate analyses were performed in subsets (older/younger than 60, men/women). Expression levels of 221 genes were associated with strength after adjustment for cofactors and for multiple statistical testing, including ALAS2 (rate-limiting enzyme in heme synthesis), PRF1 (perforin, a cytotoxic protein associated with inflammation), IGF1R, and IGF2BP2 (both insulin like growth factor related). We identified statistical enrichment for hemoglobin biosynthesis, innate immune activation, and the stress response. Ten genes were associated only in younger individuals, four in men only and one in women only. For example, PIK3R2 (a negative regulator of PI3K/AKT growth pathway) was negatively associated with muscle strength in younger (<60 yr) individuals but not older (≥ 60 yr). We also show that 115 genes (52%) have not previously been linked to muscle in NCBI PubMed abstracts. This first large-scale transcriptome study of muscle strength in human adults confirmed associations with known pathways and provides new evidence for over half of the genes identified. There may be age- and sex-specific gene expression signatures in blood for muscle strength. PMID:26487704

  8. Gene transcripts associated with muscle strength: a CHARGE meta-analysis of 7,781 persons

    PubMed Central

    Joehanes, R.; Kacprowski, T.; Peters, M.; Jansen, R.; Karasik, D.; Kiel, D. P.; Harries, L. W.; Teumer, A.; Powell, J.; Levy, D.; Lin, H.; Lunetta, K.; Munson, P.; Bandinelli, S.; Henley, W.; Hernandez, D.; Singleton, A.; Tanaka, T.; van Grootheest, G.; Hofman, A.; Uitterlinden, A. G.; Biffar, R.; Gläser, S.; Homuth, G.; Malsch, C.; Völker, U.; Penninx, B.; van Meurs, J. B. J.; Ferrucci, L.; Kocher, T.; Murabito, J.

    2015-01-01

    Lower muscle strength in midlife predicts disability and mortality in later life. Blood-borne factors, including growth differentiation factor 11 (GDF11), have been linked to muscle regeneration in animal models. We aimed to identify gene transcripts associated with muscle strength in adults. Meta-analysis of whole blood gene expression (overall 17,534 unique genes measured by microarray) and hand-grip strength in four independent cohorts (n = 7,781, ages: 20–104 yr, weighted mean = 56), adjusted for age, sex, height, weight, and leukocyte subtypes. Separate analyses were performed in subsets (older/younger than 60, men/women). Expression levels of 221 genes were associated with strength after adjustment for cofactors and for multiple statistical testing, including ALAS2 (rate-limiting enzyme in heme synthesis), PRF1 (perforin, a cytotoxic protein associated with inflammation), IGF1R, and IGF2BP2 (both insulin like growth factor related). We identified statistical enrichment for hemoglobin biosynthesis, innate immune activation, and the stress response. Ten genes were associated only in younger individuals, four in men only and one in women only. For example, PIK3R2 (a negative regulator of PI3K/AKT growth pathway) was negatively associated with muscle strength in younger (<60 yr) individuals but not older (≥60 yr). We also show that 115 genes (52%) have not previously been linked to muscle in NCBI PubMed abstracts. This first large-scale transcriptome study of muscle strength in human adults confirmed associations with known pathways and provides new evidence for over half of the genes identified. There may be age- and sex-specific gene expression signatures in blood for muscle strength. PMID:26487704

  9. Muscle pathology, limb strength, walking gait, respiratory function and neurological impairment establish disease progression in the p.N155K canine model of X-linked myotubular myopathy

    PubMed Central

    Goddard, Melissa A.; Mack, David L.; Czerniecki, Stefan M.; Kelly, Valerie E.; Snyder, Jessica M.; Grange, Robert W.; Lawlor, Michael W.; Smith, Barbara K.; Beggs, Alan H.

    2015-01-01

    Background Loss-of-function mutations in the myotubularin (MTM1) gene cause X-linked myotubular myopathy (XLMTM), a fatal, inherited pediatric disease that affects the entire skeletal musculature. Labrador retriever dogs carrying an MTM1 missense mutation exhibit strongly reduced synthesis of myotubularin, the founder member of a lipid phosphatase required for normal skeletal muscle function. The resulting canine phenotype resembles that of human patients with comparably severe mutations, and survival does not normally exceed 4 months. Methods We studied MTM1 mutant dogs (n=7) and their age-matched control littermates (n=6) between the ages of 10 and 25 weeks. Investigators blinded to the animal identities sequentially measured limb muscle pathology, fore- and hind limb strength, walking gait, respiratory function and neurological impairment. Results MTM1-mutant puppies display centrally-nucleated myofibers of reduced size and disrupted sarcotubular architecture progressing until the end of life, an average of 17 weeks. In-life measures of fore- and hind limb strength establish the rate at which XLMTM muscles weaken, and their corresponding decrease in gait velocity and stride length. Pulmonary function tests in affected dogs reveal a right-shifted relationship between peak inspiratory flow (PIF) and inspiratory time (TI); neurological assessments indicate that affected puppies as young as 10 weeks show early signs of neurological impairment (neurological severity score, NSS =8.6±0.9) with progressive decline (NSS =5.6±1.7 at 17 weeks-of-age). Conclusions Our findings document the rate of disease progression in a large animal model of XLMTM and lay a foundation for preclinical studies. PMID:26605308

  10. Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy in Resistance-Trained Men.

    PubMed

    Schoenfeld, Brad J; Pope, Zachary K; Benik, Franklin M; Hester, Garrett M; Sellers, John; Nooner, Josh L; Schnaiter, Jessica A; Bond-Williams, Katherine E; Carter, Adrian S; Ross, Corbin L; Just, Brandon L; Henselmans, Menno; Krieger, James W

    2016-07-01

    Schoenfeld, BJ, Pope, ZK, Benik, FM, Hester, GM, Sellers, J, Nooner, JL, Schnaiter, JA, Bond-Williams, KE, Carter, AS, Ross, CL, Just, BL, Henselmans, M, and Krieger, JW. Longer interset rest periods enhance muscle strength and hypertrophy in resistance-trained men. J Strength Cond Res 30(7): 1805-1812, 2016-The purpose of this study was to investigate the effects of short rest intervals normally associated with hypertrophy-type training versus long rest intervals traditionally used in strength-type training on muscular adaptations in a cohort of young, experienced lifters. Twenty-one young resistance-trained men were randomly assigned to either a group that performed a resistance training (RT) program with 1-minute rest intervals (SHORT) or a group that employed 3-minute rest intervals (LONG). All other RT variables were held constant. The study period lasted 8 weeks with subjects performing 3 total body workouts a week comprised 3 sets of 8-12 repetition maximum (RM) of 7 different exercises per session. Testing was performed prestudy and poststudy for muscle strength (1RM bench press and back squat), muscle endurance (50% 1RM bench press to failure), and muscle thickness of the elbow flexors, triceps brachii, and quadriceps femoris by ultrasound imaging. Maximal strength was significantly greater for both 1RM squat and bench press for LONG compared to SHORT. Muscle thickness was significantly greater for LONG compared to SHORT in the anterior thigh, and a trend for greater increases was noted in the triceps brachii (p = 0.06) as well. Both groups saw significant increases in local upper body muscle endurance with no significant differences noted between groups. This study provides evidence that longer rest periods promote greater increases in muscle strength and hypertrophy in young resistance-trained men. PMID:26605807

  11. Effects of strength training on muscle cellular outcomes in prostate cancer patients on androgen deprivation therapy.

    PubMed

    Nilsen, T S; Thorsen, L; Fosså, S D; Wiig, M; Kirkegaard, C; Skovlund, E; Benestad, H B; Raastad, T

    2016-09-01

    Androgen deprivation therapy (ADT) improves life expectancy in prostate cancer (PCa) patients, but is associated with adverse effects on muscle mass. Here, we investigated the effects of strength training during ADT on muscle fiber cross-sectional area (CSA) and regulators of muscle mass. PCa patients on ADT were randomized to 16 weeks of strength training (STG) (n = 12) or a control group (CG; n = 11). Muscle biopsies were obtained from m. vastus lateralis and analyzed by immunohistochemistry and western blot. Muscle fiber CSA increased with strength training (898 μm(2) , P = 0.04), with the only significant increase observed in type II fibers (1076 μm(2) , P = 0.03). There was a trend toward a difference in mean change between groups myonuclei number (0.33 nuclei/fiber, P = 0.06), with the only significant increase observed in type I fibers, which decreased the myonuclear domain size of type I fibers (P = 0.05). Satellite cell numbers and the content of androgen receptor and myostatin remained unchanged. Sixteen weeks of strength training during ADT increased type II fiber CSA and reduced myonuclear domain in type I fibers in PCa patients. The increased number of satellite cells normally seen following strength training was not observed. PMID:26282343

  12. Effects of increasing physical activity on foot structure and ankle muscle strength in adults with obesity

    PubMed Central

    Zhao, Xiaoguang; Tsujimoto, Takehiko; Kim, Bokun; Katayama, Yasutomi; Wakaba, Kyousuke; Wang, Zhennan; Tanaka, Kiyoji

    2016-01-01

    [Purpose] The purpose of this study was to examine the effects of increasing physical activity on foot structure and ankle muscle strength in adults with obesity and to verify whether the rate of change in foot structure is related to that in ankle muscle strength. [Subjects and Methods] Twenty-seven adults with obesity completed a 12-week program in which the intensity of physical activity performed was gradually increased. Physical activity was monitored using a three-axis accelerometer. Foot structure was assessed using a three-dimensional foot scanner, while ankle muscle strength was measured using a dynamometry. [Results] With the increasing physical activity, the participants’ feet became thinner (the rearfoot width, instep height, and girth decreased) and the arch became higher (the arch height index increased) and stiffer (the arch stiffness index increased); the ankle muscle strength also increased after the intervention. Additionally, the changes in the arch height index and arch stiffness index were not associated with changes in ankle muscle strength. [Conclusion] Increasing physical activity may be one possible approach to improve foot structure and function in individuals with obesity.

  13. Effects of Massage on Muscular Strength and Proprioception After Exercise-Induced Muscle Damage.

    PubMed

    Shin, Mal-Soon; Sung, Yun-Hee

    2015-08-01

    Exercise-induced muscle damage (EIMD), which is commonly associated with eccentric exercise, unaccustomed exercise, and resistance training, may lead to delayed onset muscle soreness, swelling, decreased muscle strength, and range of motion. Many researchers have evaluated various interventions to treat the signs and symptoms of EIMD. However, the effects of massage after EIMD are unclear. Here, we investigated the effect of massage on muscle strength and proprioception after EIMD. All subjects randomly were divided into an EIMD-treated control group (n = 10) and a massage-treated after EIMD experimental group (n = 11). Exercise-induced muscle damage was induced by repeated exercise. Massage treatment was provided by physiotherapist for 15 minutes. It consists of light stroking, milking, friction, and skin rolling. Lactate was evaluated by Lactate Pro analyzer in pre- and postexercise. Surface electromyography (muscle activity) and sonography (muscle thickness) were used to confirm the muscular characteristics. Proprioception was investigated by dual inclinometer. As a result, massage treatment on the gastrocnemius after EIMD increased activation of the medial gastrocnemius during contraction (p ≤ 0.05). In the lateral and medial gastrocnemius, the θs, which is the angle between muscle fibers and superficial aponeurosis, showed a significant change (p ≤ 0.05). However, there are no differences in the θd, which is the angle between muscle fibers and deep aponeurosis. We also found that proprioceptive acuity in the ankle joint was significantly greater in the massage-treated experimental group compared with that in the control group (p ≤ 0.05). These findings suggest that massage of the gastrocnemius after EIMD can improve muscle strength and proprioception by influencing the superficial layer of the gastrocnemius. PMID:25226328

  14. Inspiratory flow dynamics during phrenic nerve stimulation in awake normals during nasal breathing.

    PubMed

    Sériès, F; Demoule, A; Marc, I; Sanfaçon, C; Derenne, J P; Similowski, T

    1999-08-01

    The loss of upper airway (UA) dilators preactivation before inspiratory muscle contraction is an important determinant of the pathophysiology of obstructive sleep apnea. We hypothetized that phrenic nerve stimulation could provide a practical way to explore the effects of the dissociation between UA dilators and inspiratory muscles, and possibly to determine UA critical closing pressure during wakefulness. The pattern of inspiratory airflow was therefore studied in normal awake subjects during diaphragm twitches induced by either electrical phrenic stimulation (ES) or cervical magnetic stimulation (CMS) (n = 9) and with and without a nasal stent during ES (n = 7). End-expiratory stimulations applied during exclusive nasal breathing induced 200 to 300 ms twitch inspiratory flow. The average maximal twitch flow of flow-limited twitches was higher during CMS than ES (1.18 +/- 0.29 L. PMID:10430737

  15. Muscle strength as a predictor of onset of ADL dependence in people aged 75 years.

    PubMed

    Rantanen, Taina; Avlund, Kirsten; Suominen, Harri; Schroll, Marianne; Frändin, Kerstin; Pertti, Era

    2002-06-01

    The aim of this prospective study over 5 years was to examine maximal isometric strength of multiple muscle groups as a predictor of losing independence in activities of daily living (ADL). The participants were from the Nordic Research on Aging (NORA75). These analyses are restricted to 567 people who at baseline were independent in ADL and participated in strength tests, and who five years later participated in follow-up ADL assessments. Tests on maximal isometric strength of hand grip, elbow flexion, knee extension and trunk flexion and extension were done using adjustable dynamometers. For each muscle group tested, three equal groups were formed for men and women separately based on distributions of results. Those who reported being unable or needing help for eating, dressing, bathing, toileting, walking indoors or transferring from a bed or a chair were rated as ADL dependent. Of the 227 initially ADL independent men, 21 (9.3%) became dependent in ADL. In women, the figures were 30 (8.8%) of 340. Multiple logistic regression models were used to predict the risk of ADL dependence in groups based on strength tertiles. After confirming that the association of muscle strength and incident ADL-dependence was similar in men and women, both genders were included in the same analyses adjusted for body weight and height, gender and research locality. Gender specific cut-offs were used for strength tertiles. All the strength tests predicted ADL dependence, with those being in the lowest tertile having two to three times greater risks than those in the highest tertile of strength. Further adjustments for chronic diseases did not materially change the results. Strength tests could be used to identify people who are still independent in ADL but who are at increased risk of becoming dependent because of poor muscle strength, and who could reduce their risk by strengthening exercises. PMID:12475129

  16. The reliability of evaluation of hip muscle strength in rehabilitation robot walking training.

    PubMed

    Huang, Qiuchen; Zhou, Yue; Yu, Lili; Gu, Rui; Cui, Yao; Hu, Chunying

    2015-10-01

    [Purpose] The primary purpose of this study was to evaluate the intraclass correlation coefficient in obtaining the torque of the hip muscle strength during a robot-assisted rehabilitation treatment. [Subjects] Twenty-four patients (15 males, 9 females) with spinal cord injury participated in the study. [Methods] The subjects were asked to walk during robot-assisted rehabilitation, and the torque of the muscle strength which was measured at hip joint flexion angles of -15, -10, -5, 0, 5, 10, 15, 20, 25, and 30 degrees. [Results] The intraclass correlation coefficient of the torque of the hip muscle strength measured by the rehabilitation training robot was excellent. [Conclusion] Our results show that measurement of torque can be used as an objective assessment of treatment with RAT. PMID:26644646

  17. Weight loss may be a better approach for managing musculoskeletal conditions than increasing muscle mass and strength

    PubMed Central

    Kim, Bokun; Tsujimoto, Takehiko; So, Rina; Zhao, Xiaoguang; Suzuki, Shun; Kim, Taeho; Tanaka, Kiyoji

    2015-01-01

    To prevent or remedy musculoskeletal conditions, the relationship between obesity and the characteristics of muscle mass and strength need to be clarified. [Subjects and Methods] A total of 259 Japanese males aged 30–64 years were classified into 4 groups according to the Japanese obesity criteria. Body composition was evaluated, and handgrip strength and knee extensor strength were measured for the upper and lower extremities, respectively. Physical performance was evaluated with a jump test. [Results] Obesity was positively correlated with skeletal muscle mass index, percentage of whole-body fat, and leg muscle strength and negatively correlated with the percentage of muscle mass index, body weight-normalized handgrip strength, and knee extensor strength, and the jump test results. [Conclusion] Weight loss may be a better approach than increasing muscle mass and strength to improve musculoskeletal conditions in obese adult males. PMID:26834353

  18. LOWER ESOPHAGEAL SPHINCTER PRESSURE MEASUREMENT UNDER STANDARDIZED INSPIRATORY MANEUVEURS

    PubMed Central

    RIBEIRO, Jeany Borges e Silva; DIÓGENES, Esther Cristina Arruda Oliveira; BEZERRA, Patrícia Carvalho; COUTINHO, Tanila Aguiar Andrade; de ALMEIDA, Cícera Geórgia Félix; SOUZA, Miguel Ângelo Nobre e

    2015-01-01

    Background: Through rhythmic variations, the diaphragm influence lower esophageal sphincter (LES) pressure acting as an external sphincter. LES pressure recording is characterized by increased pressure in inspiration due to contraction of the diaphragmatic crura that involves the sphincter. Aim: To describe a method of measuring LES pressure during standardized inspiratory maneuvers with increasing loads. Methods: The study population comprised of eight healthy female volunteers (average age of 31.5 years). An esophageal high-resolution manometry and impedance system was used for measuring the LES pressure during 3-second inspiratory efforts under 12, 24 and 48 cm H2O loads (Threshold maneuvers). Results: There was a significant difference between the average maximum LES pressure and the average maximum basal LES pressure during the first (76.19±17.92 difference, p=0.0008), second (86.92±19.01 difference, p=0.0004), and third seconds of the maneuver (90.86±17.93 difference, p=0.0002), with 12, 24 and 48 cmH2O loads. Conclusion: This maneuver is a standardization of the inspiratory LES pressure and may better differentiate patients with reflux disease from healthy individuals, and may also be useful for monitoring the treatment of these patients through inspiratory muscle training. PMID:26537140

  19. Relationships of ultrasound measures of intrinsic foot muscle cross-sectional area and muscle volume with maximum toe flexor muscle strength and physical performance in young adults

    PubMed Central

    Abe, Takashi; Tayashiki, Kota; Nakatani, Miyuki; Watanabe, Hironori

    2016-01-01

    [Purpose] To investigate the relationships between toe flexor muscle strength with (TFS-5-toes) and without (TFS-4-toes) the contribution of the great toe, anatomical and physiological muscle cross-sectional areas (CSA) of intrinsic toe flexor muscle and physical performance were measured. [Subjects] Seventeen men (82% sports-active) and 17 women (47% sports-active), aged 20 to 35 years, volunteered. [Methods] Anatomical CSA was measured in two intrinsic toe flexor muscles (flexor digitorum brevis [FDB] and abductor hallucis) by ultrasound. Muscle volume and muscle length of the FDB were also estimated, and physiological CSA was calculated. [Results] Both TFS-5-toes and TFS-4-toes correlated positively with walking speed in men (r=0.584 and r=0.553, respectively) and women (r=0.748 and r=0.533, respectively). Physiological CSA of the FDB was significantly correlated with TFS-5-toes (r=0.748) and TFS-4-toes (r=0.573) in women. In men, physiological CSA of the FDB correlated positively with TFS-4-toes (r=0.536), but not with TFS-5-toes (r=0.333). [Conclusion] Our results indicate that physiological CSA of the FDB is moderately associated with TFS-4-toes while toe flexor strength correlates with walking performance. PMID:26957721

  20. Effect of Expiratory Resistive Loading in Expiratory Muscle Strength Training on Orbicularis Oris Muscle Activity

    PubMed Central

    Yanagisawa, Yukio; Matsuo, Yoshimi; Shuntoh, Hisato; Horiuchi, Noriaki

    2014-01-01

    [Purpose] The purpose of this study was to elucidate the effect of expiratory resistive loading on orbicularis oris muscle activity. [Subjects] Subjects were 23 healthy individuals (11 males, mean age 25.5±4.3 years; 12 females, mean age 25.0±3.0 years). [Methods] Surface electromyography was performed to measure the activity of the orbicularis oris muscle during maximum lip closure and resistive loading at different expiratory pressures. Measurement was performed at 10%, 30%, 50%, and 100% of maximum expiratory pressure (MEP) for all subjects. The t-test was used to compare muscle activity between maximum lip closure and 100% MEP, and analysis of variance followed by multiple comparisons was used to compare the muscle activities observed at different expiratory pressures. [Results] No significant difference in muscle activity was observed between maximum lip closure and 100% MEP. Analysis of variance with multiple comparisons revealed significant differences among the different expiratory pressures. [Conclusion] Orbicularis oris muscle activity increased with increasing expiratory resistive loading. PMID:24648644

  1. Motor effort training with low exercise intensity improves muscle strength and descending command in aging.

    PubMed

    Jiang, Changhao; Ranganathan, Vinoth K; Zhang, Junmei; Siemionow, Vlodek; Yue, Guang H

    2016-06-01

    This study explored the effect of high mental effort training (MET) and conventional strength training (CST) on increasing voluntary muscle strength and brain signal associated with producing maximal muscle force in healthy aging. Twenty-seven older adults (age: 75 ± 7.9 yr, 8 women) were assigned into 1 of 3 groups: MET group-trained with low-intensity (30% maximal voluntary contraction [MVC]) physical exercise combined with MET, CST group-trained with high-intensity muscle contractions, or control (CTRL) group-no training of any kind. MET and CST lasted for 12 weeks (5 sessions/week). The participants' elbow flexion strength of the right arm, electromyography (EMG), and motor activity-related cortical potential (MRCP) directly related to the strength production were measured before and after training. The CST group had the highest strength gain (17.6%, P <0.001), the MET group also had significant strength gain (13.8%, P <0.001), which was not statistically different from that of the CST group even though the exercise intensity for the MET group was only at 30% MVC level. The CTRL group did not have significant strength changes. Surprisingly, only the MET group demonstrated a significant augmentation in the MRCP (29.3%, P <0.001); the MRCP increase in CST group was at boarder-line significance level (12.11%, P = 0.061) and that for CTRL group was only 4.9% (P = 0.539). These results suggest that high mental effort training combined with low-intensity physical exercise is an effective method for voluntary muscle strengthening and this approach is especially beneficial for those who are physically weak and have difficulty undergoing conventional strength training. PMID:27310942

  2. Motor effort training with low exercise intensity improves muscle strength and descending command in aging

    PubMed Central

    Jiang, Changhao; Ranganathan, Vinoth K.; Zhang, Junmei; Siemionow, Vlodek; Yue, Guang H.

    2016-01-01

    Abstract This study explored the effect of high mental effort training (MET) and conventional strength training (CST) on increasing voluntary muscle strength and brain signal associated with producing maximal muscle force in healthy aging. Twenty-seven older adults (age: 75 ± 7.9 yr, 8 women) were assigned into 1 of 3 groups: MET group—trained with low-intensity (30% maximal voluntary contraction [MVC]) physical exercise combined with MET, CST group—trained with high-intensity muscle contractions, or control (CTRL) group—no training of any kind. MET and CST lasted for 12 weeks (5 sessions/week). The participants’ elbow flexion strength of the right arm, electromyography (EMG), and motor activity-related cortical potential (MRCP) directly related to the strength production were measured before and after training. The CST group had the highest strength gain (17.6%, P <0.001), the MET group also had significant strength gain (13.8%, P <0.001), which was not statistically different from that of the CST group even though the exercise intensity for the MET group was only at 30% MVC level. The CTRL group did not have significant strength changes. Surprisingly, only the MET group demonstrated a significant augmentation in the MRCP (29.3%, P <0.001); the MRCP increase in CST group was at boarder-line significance level (12.11%, P = 0.061) and that for CTRL group was only 4.9% (P = 0.539). These results suggest that high mental effort training combined with low-intensity physical exercise is an effective method for voluntary muscle strengthening and this approach is especially beneficial for those who are physically weak and have difficulty undergoing conventional strength training. PMID:27310942

  3. Comparison of pelvic floor muscle strength evaluations in nulliparous and primiparous women: a prospective study

    PubMed Central

    Gameiro, Mônica Orsi; Sousa, Vanessa Oliveira; Gameiro, Luiz Felipe; Muchailh, Rosana Carneiro; Padovani, Carlos Roberto; Amaro, João Luiz

    2011-01-01

    OBJECTIVE: This study aimed to compare the pelvic floor muscle strength of nulliparous and primiparous women. METHODS: A total of 100 women were prospectively distributed into two groups: Group 1 (G1) (n = 50) included healthy nulliparous women, and Group 2 (G2) (n = 50) included healthy primiparous women. Pelvic floor muscle strength was subjectively evaluated using transvaginal digital palpation. Pelvic floor muscle strength was objectively assessed using a portable perineometer. All of the parameters were evaluated simultaneously in G1 and were evaluated in G2 during the 20th and 36th weeks of pregnancy and 45 days after delivery. RESULTS: In G2, 14 women were excluded because they left the study before the follow-up evaluation. The median age was 23 years in G1 and 22 years in G2; there was no significant difference between the groups. The average body mass index was 21.7 kg/m2 in G1 and 25.0 kg/m2 in G2; there was a significant difference between the groups (p = 0.0004). In G2, transvaginal digital palpation evaluation showed significant impairments of pelvic floor muscle strength at the 36th week of pregnancy (p = 0.0006) and 45 days after vaginal delivery (p = 0.0001) compared to G1. Objective evaluations of pelvic floor muscle strength in G2 revealed a significant decrease 45 days after vaginal delivery compared to nulliparous patients. CONCLUSION: Pregnancy and vaginal delivery may cause weakness of the pelvic floor muscles. PMID:21915489

  4. Respiratory muscle activity and oxygenation during sleep in patients with muscle weakness.

    PubMed

    White, J E; Drinnan, M J; Smithson, A J; Griffiths, C J; Gibson, G J

    1995-05-01

    Patients with respiratory muscle weakness show nocturnal hypoventilation, with oxygen desaturation particularly during rapid eye movement (REM) sleep, but evidence in individuals with isolated bilateral diaphragmatic paresis (BDP) is conflicting. The effect of sleep on relative activity of the different respiratory muscles of such patients and, consequently, the precise mechanisms causing desaturation have not been clarified. We have studied eight patients, four with generalized muscle weakness and four with isolated BDP during nocturnal sleep with measurements including oxygen saturation and surface electromyographic (EMG) activity of various respiratory muscle groups. Nocturnal oxygenation correlated inversely with postural fall in vital capacity, an index of diaphragmatic strength. During REM sleep, hypopnoea and desaturation occurred particularly during periods of rapid eye movements (phasic REM sleep). In most subjects, such events were "central" in type and associated with marked suppression of intercostal muscle activity, but two subjects had recurrent desaturation due to "obstructive" hypopnoea and/or apnoea. Expiratory activity of the external oblique muscle was present whilst awake and during non-rapid eye movement (NREM) sleep in seven of the eight subjects in the semirecumbent posture. This probably represents an "accessory inspiratory" effect, which aids passive caudal diaphragmatic motion as the abdominal muscles relax at the onset of inspiration. Expiratory abdominal muscle activity was suppressed in phasic REM sleep, suggesting that loss of this "accessory inspiratory" effect may contribute to "central" hypopnoea. We conclude that, in patients with muscle weakness, nocturnal oxygenation correlates with diaphragmatic strength.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7656954

  5. Upper Extremity Muscle Volumes and Functional Strength After Resistance Training in Older Adults

    PubMed Central

    Daly, Melissa; Vidt, Meghan E.; Eggebeen, Joel D.; Simpson, W. Greg; Miller, Michael E.; Marsh, Anthony P.; Saul, Katherine R.

    2014-01-01

    Aging leads to a decline in strength and an associated loss of independence. The authors examined changes in muscle volume, maximum isometric joint moment, functional strength, and 1-repetition maximum (1RM) after resistance training (RT) in the upper extremity of older adults. They evaluated isometric joint moment and muscle volume as predictors of functional strength. Sixteen healthy older adults (average age 75 ± 4.3 yr) were randomized to a 6-wk upper extremity RT program or control group. The RT group increased 1RM significantly (p < .01 for all exercises). Compared with controls, randomization to RT led to greater functional pulling strength (p = .003), isometric shoulder-adduction moment (p = .041), elbow-flexor volume (p = .017), and shoulder-adductor volume (p = .009). Shoulder-muscle volumes and isometric moments were good predictors of functional strength. The authors conclude that shoulder strength is an important factor for performing functional reaching and pulling tasks and a key target for upper extremity RT interventions. PMID:22952203

  6. Respiration in man affected by TVR contractions elicited in inspiratory and expiratory intercostal muslces.

    PubMed

    Homma, I; Eklund, G; Hagbarth, K E

    1978-12-01

    Vibration-induced effects on respiration in man were studied by recording the electrical activity (EMG) from the intercostal muscles and the diaphragm. The vibration was applied in an upper thoracic region where inspiratory muscle activity prevailed or in a lower thoracic region where expiratory muscle activity prevailed. The effects were also studied by recording the movements of the thorax and the respiratory air flow. Sustained vibration in the upper region enhanced the activity of the underlying inspiratory muscles and caused an expansion of the rib cage whereas it had little or weak effects on diaphragm-activity or on expiratory intercostal muscles. Sustained vibration in the lower region enhanced the activity of the underlying expiratory muscles, often inhibited the inspiratory activity and caused a depression of the rib cage. It also tended to inhibit the diaphragm activity. It was also found that bilateral vibration, timed by the respiratory movements and alternating between upper and lower regions could aid or counteract the ventilation if it was applied respectively 'in phase' or 'out of phase' with the rhythmical contractions in the underlying muscles. The motor responses described are largely explicable in terms of tonic vibration reflexes (TVR) arising in the inspiratory and expiratory intercostal muscles underlying the vibrators. PMID:741110

  7. MMP(-2) expression in skeletal muscle after strength training.

    PubMed

    Deus, A P L; Bassi, D; Simões, R P; Oliveira, C R; Baldissera, V; Marqueti, R de Cássia; Araujo, H S S; Arena, R; Borghi-Silva, A

    2012-02-01

    The aim of this study was to assess the effects of resistance training on ladders (RTL) on MMP(-2) expression and blood lactate concentration [La-]. 30 male (3 months of age), albino rats were divided into 3 groups: sedentary control (SC, n=10), low resistance exercise training (Low-IntRT, n=10) and high-intensive exercise training (High-IntRT, n=10). Animals of High-IntRT were submitted to a progressively increasing overload in relation to body weight until exhaustion, while the Low-IntRT group performed the same exercise regimen with no external load. The program had a frequency of 3 times per week over 8 weeks. MMP(-2) expression of tibialis anterior muscle and [La-] were measured. While there was a significant increase of MMP(-2) (pro-form) in both groups, only High-IntRT significantly increased MMP(-2) in active-form (p<0.05). Both trained groups exhibited an increase in [La-] when compared to controls, however, the increase in [La-] was significantly higher in the High-IntRT compared to Low-IntRT (p<0.05). Strong correlation was found between MMP(-2) (active form) and [La-] in High-IntRT (r=0.91). RTL in using low and high-intensity exercise can serve as a model to demonstrate different responses of MMP(-2) expression in an animal model. It appears active form expression of MMP(-2) is modulated by exercise intensity. PMID:22095325

  8. Physical characteristics as predictors of quadriceps muscle isometric strength: a pilot study.

    PubMed

    Hamzat, T K

    2001-09-01

    This one-group experimental study was carried out to investigate the relationship between isometric strength of quadriceps femoris muscle group and physical characteristics of subjects namely: age; weight; and height. Prediction equations were also derived for quadriceps isometric strength from these physical characteristics. Fifty volunteer, right-legged healthy normal male subjects participated in the study. They were aged between 19 and 27 years. The subjects had no previous history of neuromuscular and skeletal injuries to the lower limbs. Their ages, height and weight were measured in years, centimeters and kilograms, respectively. Quadriceps isometric strength was measured using an adapted cable tensiometer (ACT) and recorded in kilogramforce (kgf). Pearson's product correlation co-efficient (r) was used to study the relationship between quadriceps strength and each of age, height and weight. Linear and multiple regression analyses were also carried out. The result showed a high and positive Pearson's moment correlation coefficient (r) between quadriceps isometric strength and each of weight and height. A positive but low correlation (r) was also found between age and quadriceps isometric strength. Prediction equations were also derived from the linear and regression analyses. The study concluded that there was linear relationship between the physical characteristics and quadriceps isometric strength. It was recommended that the prediction equation be employed to estimate quadriceps strength while setting muscle strengthening goals in the clinics during medical rehabilitation for patients within the age range used in this study. PMID:14510124

  9. Effects of muscle strength asymmetry between left and right on isokinetic strength of the knee and ankle joints depending on athletic performance level

    PubMed Central

    Jeon, Kyoungkyu; Chun, Sungyung; Seo, Byoungdo

    2016-01-01

    [Purpose] The aim of this study was to collect basic data on the effect of asymmetry on the muscle strength of the left and right knee and ankle joints of soccer players at varying athletic performance levels, to guide the development of improved exercise programs. [Subjects and Methods] Forty-nine soccer players at three athletic performance levels participated: 15 professional, 16 amateur, and 18 college. Knee extensor and flexor strength were measured at 60°/sec and 180°/sec, and ankle plantar flexor and dorsiflexor strength were measured at 30°/sec and at 120°/sec. Variables were analyzed by one-way ANOVA. [Results] College soccer players showed greater muscle strength at 60°/sec and 180°/sec in the knee extension muscles of both the right and the left sides, lower muscle strength at 30°/sec and 120°/sec in the dorsiflexor of the right ankle, and similar levels of asymmetry between left and right. The maximum muscle strength on the same side significantly differed in the right ankle joint, with asymmetry between left and right at 30°/sec and 120°/sec. [Conclusion] These findings suggest that muscle strength asymmetry in the ankle joint may lead to counterbalancing muscle strengthening of the knee joint to maintain the center of body mass. PMID:27190469

  10. Effects of muscle strength asymmetry between left and right on isokinetic strength of the knee and ankle joints depending on athletic performance level.

    PubMed

    Jeon, Kyoungkyu; Chun, Sungyung; Seo, Byoungdo

    2016-04-01

    [Purpose] The aim of this study was to collect basic data on the effect of asymmetry on the muscle strength of the left and right knee and ankle joints of soccer players at varying athletic performance levels, to guide the development of improved exercise programs. [Subjects and Methods] Forty-nine soccer players at three athletic performance levels participated: 15 professional, 16 amateur, and 18 college. Knee extensor and flexor strength were measured at 60°/sec and 180°/sec, and ankle plantar flexor and dorsiflexor strength were measured at 30°/sec and at 120°/sec. Variables were analyzed by one-way ANOVA. [Results] College soccer players showed greater muscle strength at 60°/sec and 180°/sec in the knee extension muscles of both the right and the left sides, lower muscle strength at 30°/sec and 120°/sec in the dorsiflexor of the right ankle, and similar levels of asymmetry between left and right. The maximum muscle strength on the same side significantly differed in the right ankle joint, with asymmetry between left and right at 30°/sec and 120°/sec. [Conclusion] These findings suggest that muscle strength asymmetry in the ankle joint may lead to counterbalancing muscle strengthening of the knee joint to maintain the center of body mass. PMID:27190469

  11. In vivo assessment of contractile strength distinguishes differential gene function in skeletal muscle of zebrafish larvae.

    PubMed

    Martin, Brit L; Gallagher, Thomas L; Rastogi, Neha; Davis, Jonathan P; Beattie, Christine E; Amacher, Sharon L; Janssen, Paul M L

    2015-10-01

    The accessible genetics and extensive skeletal musculature of the zebrafish make it a versatile and increasingly used model for studying muscle contraction. We here describe the development of an in vivo assay for measuring the contractile force of intact zebrafish at the larval stage. In addition, as proof of applicability, we have used this assay to quantify contractile strength of zebrafish larvae in a morphant model of deranged rbfox function. Average maximum tetanic (180 Hz) whole body forces produced by wild-type larvae at 2, 3, 4, and 5 days postfertilization amounted to 3.0, 7.2, 9.1, and 10.8 mN, respectively. To compare at potentially different stages of muscle development, we developed an immunohistological assay for empirically determining the cross-sectional area of larval trunk skeletal muscle to quantify muscle-specific force per cross-sectional area. At 4-5 days postfertilization, specific force amounts to ∼ 300 mN/mm(2), which is similar to fully developed adult mammalian skeletal muscle. We used these assays to measure contractile strength in zebrafish singly or doubly deficient for two rbfox paralogs, rbfox1l and rbfox2, which encode RNA-binding factors shown previously to modulate muscle function and muscle-specific splicing. We found rbfox2 morphants produce maximal tetanic forces similar to wild-type larvae, whereas rbfox1l morphants demonstrate significantly impaired function. rbfox1l/rbfox2 morphants are paralyzed, and their lack of contractile force production in our assay suggests that paralysis is a muscle-autonomous defect. These quantitative functional results allow measurement of muscle-specific phenotypes independent of neural input. PMID:26251513

  12. Effects of 5 weeks of lower limb suspension on muscle size and strength

    NASA Technical Reports Server (NTRS)

    Tesch, P. A.; Ploutz, L. L.; Dudley, G. A.

    1994-01-01

    Lack of weight-bearing, as occurs in space, appears to be associated with reductions in strength and mass of skeletal muscle. Very limited data, however, is at hand describing changes in skeletal muscle size and function following manned space missions. Our current knowledge therefore is mainly based on studies of space flown rats. It is obvious though that this information, only in part can be extrapolated to humans. A few bed rest studies have demonstrated that decreases in strength and muscle size are substantial. At this time, however, the magnitude or time course of such changes either in response to space flight or simulations of microgravity have not been defined. In the last few years we have employed a human model to simulate unloading of lower limb skeletal muscles that occurs in microgravity. This model was essentially adopted from the rat hindlimb suspension technique. The purpose of this study was to assess the magnitude of decreases in muscle strength and size as a result of five weeks of unilateral lower limb suspension.

  13. Relationships between Respiratory Muscle Strength and Daily Living Function in Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Wang, Hui-Yi; Chen, Chien-Chih; Hsiao, Shih-Fen

    2012-01-01

    Cerebral palsy (CP) is a common childhood disorder characterized by motor disability. Children with CP are at risk of developing significant respiratory problems associated with insufficient respiratory muscle strength. It is crucial to identify important factors which are associated with the limitations in daily living function in such children.…

  14. Angiotensin-II blockage, muscle strength, and exercise capacity in physically independent older adults

    PubMed Central

    Coelho, Vinícius A.; Probst, Vanessa S.; Nogari, Bruna M.; Teixeira, Denilson C.; Felcar, Josiane M.; Santos, Denis C.; Gomes, Marcus Vinícius M.; Andraus, Rodrigo A. C.; Fernandes, Karen B. P.

    2016-01-01

    [Purpose] This study aimed to assess the exercise capacity and muscle strength in elderly people using drugs for angiotensin-II blockage. [Subjects and Methods] Four hundred and seven older adults were recruited for this study. Data about comorbidities and medication use were recorded and the individuals were divided into three groups: control group- elderly people with normal exercise capacity (n=235); angiotensin-converting enzyme inhibitor group − individuals using angiotensin-converting enzyme inhibitors (n=140); and angiotensin-II receptor blocker group- patients using angiotensin-II receptor blockers (n= 32). Exercise capacity was evaluated by a 6-minute walking test and muscle strength was measured using a handgrip dynamometer. [Results] Patients from the angiotensin-converting enzyme inhibitor group (mean: 99 ± 12%) and the angiotensin-II receptor blocker group (mean: 101 ± 14%) showed higher predicted values in the 6-minute walking test than the control group patients (mean: 96 ± 10%). Patients from the angiotensin-converting enzyme inhibitor group (mean: 105 ± 19%) and the angiotensin-II receptor blocker group (mean: 105.1 ± 18.73%) showed higher predicted values of muscle strength than control group patients (mean: 98.15 ± 18.77%). [Conclusion] Older adults using angiotensin-converting enzyme inhibitors or angiotensin-II receptor blockers have better functional exercise capacity and muscle strength. PMID:27065543

  15. Influence of Body Composition on Lung Function and Respiratory Muscle Strength in Children With Obesity

    PubMed Central

    Costa Junior, Dirceu; Peixoto-Souza, Fabiana S.; Araujo, Poliane N.; Barbalho-Moulin, Marcela C.; Alves, Viviane C.; Gomes, Evelim L. F. D.; Costa, Dirceu

    2016-01-01

    Background Obesity affects lung function and respiratory muscle strength. The aim of the present study was to assess lung function and respiratory muscle strength in children with obesity and determine the influence of body composition on these variables. Methods A cross-sectional study was conducted involving 75 children (40 with obesity and 35 within the ideal weight range) aged 6 - 10 years. Body mass index, z score, waist circumference, body composition (tetrapolar bioimpedance), respiratory muscle strength and lung function (spirometry) were evaluated. Results Children with obesity exhibited larger quantities of both lean and fat mass in comparison to those in the ideal weight range. No significant differences were found between groups regarding the respective reference values for respiratory muscle strength. Male children with obesity demonstrated significantly lower lung function values (forced expiratory volume in the first second % (FEV1%) and FEV1/forced vital capacity % (FVC%) : 93.76 ± 9.78 and 92.29 ± 3.8, respectively) in comparison to males in the ideal weight range (99.87 ± 9.72 and 96.31 ± 4.82, respectively). The regression models demonstrated that the spirometric variables were influenced by all body composition variables. Conclusion Children with obesity demonstrated a reduction in lung volume and capacity. Thus, anthropometric and body composition characteristics may be predictive factors for altered lung function. PMID:26767078

  16. The Effects of a 10-Kilometer Run on Muscle Strength and Power.

    ERIC Educational Resources Information Center

    Gomez, Ana L.; Radzwich, Robert J.; Denegar, Craig R.; Volek, Jeff S.; Rubin, Martyn R.; Bush, Jill A.; Doan, Brandon K.; Wickham, Robbin B.; Mazzetti, Scott A.; Newton, Robert U.; French, Duncan N.; Hakkinen, Keijo; Ratamess, Nicholas A.; Kraemer, William J.

    2002-01-01

    Investigated recovery of maximal force and power following a 10-km race. Data collected on 10 healthy male distance runners pre-race, immediately post-race, and 48 hours later indicated that strength and power capabilities of these 10-km runners were for the most part restored 48 hours after the race. Only the hamstring muscle group was not fully…

  17. Reliability of Maximal Voluntary Muscle Strength and Power Testing in Older Men

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Maximal voluntary muscle strength (MVMS) and leg power are important measures of physical function in older adults. We hypothesized that performing these measures twice within 7-10 days would demonstrate a >5% increase due to learning and familiarization of the testing procedures. Methods...

  18. Wii balance board exercise improves balance and lower limb muscle strength of overweight young adults

    PubMed Central

    Siriphorn, Akkradate; Chamonchant, Dannaovarat

    2015-01-01

    [Purpose] The potential health benefits of the Nintendo Wii balance board exercise have been widely investigated. However, no study has been conducted to examine the benefits of Wii exercise for overweight young adults. The aim of this study was to investigate the effect of exercise performed on a Nintendo Wii balance board on the balance and lower limb muscle strength in overweight young adults. [Subjects and Methods] Within-subject repeated measures analysis was used. Sixteen young adults (aged 21.87±1.13 years, body mass index 24.15 ± 0.50 kg/m2) were recruited. All subjects performed an exercise program on a Wii balance board for 8 weeks (30 min/session, twice a week for 8 weeks). A NeuroCom Balance Master and a hand-held dynamometer were used to measure balance performance and lower limb muscle strength. [Results] According to the comparison of pre- and post-intervention measurements, the Wii balance board exercise program significantly improved the limit of stability parameters. There was also a significant increase in strength of four lower-limb muscle groups: the hip flexor, knee flexor, ankle dorsiflexor and ankle plantarflexor. [Conclusion] These findings suggest that a Wii balance board exercise program can be used to improve the balance and lower limb muscle strength of overweight young adults. PMID:25642034

  19. Wii balance board exercise improves balance and lower limb muscle strength of overweight young adults.

    PubMed

    Siriphorn, Akkradate; Chamonchant, Dannaovarat

    2015-01-01

    [Purpose] The potential health benefits of the Nintendo Wii balance board exercise have been widely investigated. However, no study has been conducted to examine the benefits of Wii exercise for overweight young adults. The aim of this study was to investigate the effect of exercise performed on a Nintendo Wii balance board on the balance and lower limb muscle strength in overweight young adults. [Subjects and Methods] Within-subject repeated measures analysis was used. Sixteen young adults (aged 21.87±1.13 years, body mass index 24.15 ± 0.50 kg/m(2)) were recruited. All subjects performed an exercise program on a Wii balance board for 8 weeks (30 min/session, twice a week for 8 weeks). A NeuroCom Balance Master and a hand-held dynamometer were used to measure balance performance and lower limb muscle strength. [Results] According to the comparison of pre- and post-intervention measurements, the Wii balance board exercise program significantly improved the limit of stability parameters. There was also a significant increase in strength of four lower-limb muscle groups: the hip flexor, knee flexor, ankle dorsiflexor and ankle plantarflexor. [Conclusion] These findings suggest that a Wii balance board exercise program can be used to improve the balance and lower limb muscle strength of overweight young adults. PMID:25642034

  20. Muscle strength and bone density in patients with different rheumatic conditions: cross-sectional study

    PubMed Central

    Cvijetić, Selma; Grazio, Simeon; Gomzi, Milica; Krapac, Ladislav; Nemčić, Tomislav; Uremović, Melita; Bobić, Jasminka

    2011-01-01

    Aim To explore the relationship between muscle strength and bone density in patients with different rheumatic diseases and to examine whether inflammatory arthritis was more harmful for muscle strength and bone loss than degenerative joint diseases. Methods The study included 361 men and women with a mean ± standard deviation age of 60.5 ± 11.4 years and different rheumatic conditions: regional syndromes, osteoarthritis of the hands, shoulders, knees, and hips, and inflammatory arthritis. Maximum voluntary back strength was measured by isometric dynamometry. Bone mineral density (BMD; g/cm2) of the lumbar spine, femoral neck, and distal radius was measured by dual-energy x-ray absorptiometry. Anthropometry and lifestyle characteristics were also assessed. Results Back strength was lowest in patients with hand and shoulder osteoarthritis (20.0 ± 17.9 kg), followed by patients with inflammatory arthritis (24.8 ± 19.2 kg). Patients with inflammatory arthritis had the lowest BMD at the mid-radius (0.650 ± 0.115 g/cm2) and femoral neck (0.873 ± 0.137 g/cm2), while patients with hand and shoulder osteoarthritis had the lowest BMD at the mid-radius (0.660 ± 0.101). In both sexes, muscle strength was significantly lower in patients who had lower BMD (T score<-1.0). Multiple regression analysis identified significant predictors of back strength to be spine BMD (P = 0.024) and body mass index (P = 0.004) in men and femoral neck BMD in women (P = 0.004). Conclusion Muscle strength decline may be connected to bone loss in patients with rheumatic conditions, especially those with inflammatory joint diseases. PMID:21495199

  1. Low muscle strength in late adolescence and Parkinson disease later in life

    PubMed Central

    Gustafsson, Helena; Aasly, Jan; Stråhle, Stefan; Nordström, Anna

    2015-01-01

    Objective: To evaluate maximal isometric muscle force at 18 years of age in relation to Parkinson disease (PD) later in life. Methods: The cohort consisted of 1,317,713 men who had their muscle strength measured during conscription (1969–1996). Associations between participants' muscle strength at conscription and PD diagnoses, also in their parents, were examined using multivariate statistical models. Results: After adjustment for confounders, the lowest compared to the highest fifth of handgrip strength (hazard ratio [HR] 1.38, 95% confidence interval [CI] 1.06–1.79), elbow flexion strength (HR 1.34, 95% CI 1.02–1.76), but not knee extension strength (HR 1.24, 95% CI 0.94–1.62) was associated with an increased risk of PD during follow-up. Furthermore, men whose parents were diagnosed with PD had reduced handgrip (fathers: mean difference [MD] −5.7 N [95% CI −7.3 to −4.0]; mothers: MD −5.0 N [95% CI −7.0 to −2.9]) and elbow flexion (fathers: MD −4.3 N [95% CI −5.7 to −2.9]; mothers: MD −3.9 N [95% CI −5.7 to −2.2]) strength, but not knee extension strength (fathers: MD −1.1 N [95% CI −2.9 to 0.8]; mothers: MD −0.7 N [95% CI −3.1 to 1.6]), than those with no such familial history. Conclusions: Maximal upper extremity voluntary muscle force was reduced in late adolescence in men diagnosed with PD 30 years later. The findings suggest the presence of subclinical motor deficits 3 decades before the clinical onset of PD. PMID:25841033

  2. Muscle strength, endurance and recovery in the post-infection fatigue syndrome.

    PubMed Central

    Lloyd, A R; Hales, J P; Gandevia, S C

    1988-01-01

    A test of muscle strength and "fatiguability" was administered to 20 normal subjects and 20 patients suffering from post-infection fatigue syndrome. Maximal isometric torque for the elbow flexors was measured before, during and after an endurance sequence of 18 maximal static contractions (10 s duration, 10 s rest interval). The maximal isometric strength was not significantly different between the patient and control groups. The relative torque produced at the end of the series of 18 static contractions did not differ significantly between patients and normal subjects. In the patients with post-infection fatigue syndrome there was impairment of the recovery of peak torque at 10 minutes after the endurance sequence (p less than 0.02). The prominent subjective complaint of muscle fatigue in patients with post-infection fatigue syndrome contrasts with the relatively normal behaviour of their muscles during a controlled test of fatigue. The syndrome may include a disordered perception of achieved force and exertion. PMID:2852211

  3. Test-retest reliability of isometric shoulder muscle strength measurement with a handheld dynamometer and belt

    PubMed Central

    Katoh, Munenori

    2015-01-01

    [Purpose] The aim of this study was to develop a method of measuring isometric shoulder joint muscle strength using a handheld dynamometer with a belt and investigate its test-retest reliability. [Subjects] The subjects comprised 40 healthy adults. [Methods] Six types of isometric shoulder muscle strength were measured twice, and reliability was assessed. [Results] The intraclass correlation coefficient (1, 1) values ranged from 0.976 to 0.902. The result of a Bland-Altman analysis showed differences in the types of errors between measurement items. [Conclusion] The relative reliability of isometric shoulder muscle measurement using a handheld dynamometer with a belt was high. However, analysis of absolute reliability revealed errors that may affect interpretation of values; therefore, it was considered that adapting the greater of two measurement values is appropriate. PMID:26180305

  4. The Effect of Stage II Posterior Tibial Tendon Dysfunction on Deep Compartment Muscle Strength: A New Strength Test

    PubMed Central

    Houck, Jeff R.; Nomides, Candace; Neville, Christopher Glenn; Flemister, Adolph Samuel

    2010-01-01

    Background The purpose of this study was to compare isometric subtalar inversion and forefoot adduction strength in subjects with Stage II posterior tibial tendon dysfunction (PTTD) to controls. Materials and Methods Twenty four subjects with Stage II PTTD and fifteen matched controls volunteered for this study. A force transducer (Model SML-200, Interface, Scottsdale, AZ) was connected with a resistance plate and oscilloscope (TDS 410A, Tektronix, Beaverton, OR) to the foot. Via the oscilloscope, subjects were given feedback on the amount of force produced and muscle activation of the anterior tibialis (AT) muscle. Subjects were instructed to maintain a plantar flexion force while performing a maximal voluntary subtalar inversion and forefoot adduction effort. A two-way ANOVA model with the factors including, side (involved/uninvolved) and group (control/PTTD) was used. Results The PTTD group on the involved side showed significantly decreased subtalar inversion and foot adduction strength (0.70 ± 0.24 N/Kg) compared to the uninvolved side (0.94 ± 0.24 N/Kg) and controls (involved side = 0.99 ± 0.24 N/Kg, uninvolved side = 0.97 ± 0.21 N/Kg). The average AT activation was between 11–17% for both groups, however, showing considerable variability in subjects with PTTD. Conclusion These data confirm a subtalar inversion and forefoot adduction strength deficit by 20% to 30% in subjects with Stage II PTTD. Although isolating the PT muscle is difficult, a test specific to subtalar inversion and forefoot adduction demonstrated the weakness in this population. PMID:18778667

  5. Skeletal muscle fat content is inversely associated with bone strength in young girls.

    PubMed

    Farr, Joshua N; Funk, Janet L; Chen, Zhao; Lisse, Jeffrey R; Blew, Robert M; Lee, Vinson R; Laudermilk, Monica; Lohman, Timothy G; Going, Scott B

    2011-09-01

    Childhood obesity is an established risk factor for metabolic disease. The influence of obesity on bone development, however, remains controversial and may depend on the pattern of regional fat deposition. Therefore, we examined the associations of regional fat compartments of the calf and thigh with weight-bearing bone parameters in girls. Data from 444 girls aged 9 to 12 years from the Jump-In: Building Better Bones study were analyzed. Peripheral quantitative computed tomography (pQCT) was used to assess bone parameters at metaphyseal and diaphyseal sites of the femur and tibia along with subcutaneous adipose tissue (SAT, mm(2) ) and muscle density (mg/cm(3) ), an index of skeletal muscle fat content. As expected, SAT was positively correlated with total-body fat mass (r = 0.87-0.89, p < .001), and muscle density was inversely correlated with total-body fat mass (r = -0.24 to -0.28, p < .001). Multiple linear regression analyses with SAT, muscle density, muscle cross-sectional area, bone length, maturity, and ethnicity as independent variables showed significant associations between muscle density and indices of bone strength at metaphyseal (β = 0.13-0.19, p < .001) and diaphyseal (β = 0.06-0.09, p < .01) regions of the femur and tibia. Associations between SAT and indices of bone strength were nonsignificant at all skeletal sites (β = 0.03-0.05, p > .05), except the distal tibia (β = 0.09, p = .03). In conclusion, skeletal muscle fat content of the calf and thigh is inversely associated with weight-bearing bone strength in young girls. PMID:21544865

  6. Strength and muscle activity of shoulder external rotation of subjects with and without scapular dyskinesis

    PubMed Central

    Uga, Daisuke; Nakazawa, Rie; Sakamoto, Masaaki

    2016-01-01

    [Purpose] This study aimed to clarify the relationship between scapular dyskinesis and shoulder external rotation strength and muscle activity. [Subjects and Methods] Both shoulders of 20 healthy males were evaluated. They were classified into 19 normal, 8 subtly abnormal, and 13 obviously abnormal shoulders using the scapular dyskinesis test. Subtly abnormal shoulders were subsequently excluded from the analysis. Shoulder external rotation strength and muscle activity (infraspinatus, serratus anterior, upper, middle, and lower trapezius) were measured in 2 positions using a handheld dynamometer and surface electromyography while sitting in a chair with shoulder 0° abduction and flexion (1st position), and while lying prone on the elbows with the shoulders elevated in the zero position (zero position). The strength ratio was calculated to quantify the change in strength between the positions (zero position / 1st position). [Results] In the obviously abnormal shoulder group, the strength in the 1st position was significantly stronger, the strength ratio was significantly smaller, and the serratus anterior in the zero position showed significantly lower activity than the normal shoulder group. [Conclusion] In shoulder external rotation in the zero position, in obviously abnormal shoulders, the serratus anterior is poorly recruited, weakening the shoulder external rotation strength. PMID:27190434

  7. Anti-myostatin antibody increases muscle mass and strength and improves insulin sensitivity in old mice

    PubMed Central

    Camporez, João-Paulo G.; Petersen, Max C.; Abudukadier, Abulizi; Moreira, Gabriela V.; Jurczak, Michael J.; Friedman, Glenn; Haqq, Christopher M.; Petersen, Kitt Falk; Shulman, Gerald I.

    2016-01-01

    Sarcopenia, or skeletal muscle atrophy, is a debilitating comorbidity of many physiological and pathophysiological processes, including normal aging. There are no approved therapies for sarcopenia, but the antihypertrophic myokine myostatin is a potential therapeutic target. Here, we show that treatment of young and old mice with an anti-myostatin antibody (ATA 842) for 4 wk increased muscle mass and muscle strength in both groups. Furthermore, ATA 842 treatment also increased insulin-stimulated whole body glucose metabolism in old mice, which could be attributed to increased insulin-stimulated skeletal muscle glucose uptake as measured by a hyperinsulinemic-euglycemic clamp. Taken together, these studies provide support for pharmacological inhibition of myostatin as a potential therapeutic approach for age-related sarcopenia and metabolic disease. PMID:26858428

  8. Effects of Training Attendance on Muscle Strength of Young Men after 11 Weeks of Resistance Training

    PubMed Central

    Gentil, Paulo; Bottaro, Martim

    2013-01-01

    Purpose Training attendance is an important variable for attaining optimal results after a resistance training (RT) program, however, the association of attendance with the gains of muscle strength is not well defined. Therefore, the purpose of the present study is to verify if attendance would affect muscle strength gains in healthy young males. Methods Ninety two young males with no previous RT experience volunteered to participate in the study. RT was performed 2 days a week for 11 weeks. One repetition maximum (1RM) in the bench press and knee extensors peak torque (PT) were measured before and after the training period. After the training period, a two step cluster analysis was used to classify the participants in accordance to training attendance, resulting in three groups, defined as high (92 to 100%), intermediate (80 to 91%) and low (60 to 79%) training attendance. Results According to the results, there were no significant correlations between strength gains and training attendance, however, when attendance groups were compared, the low training attendance group showed lower increases in 1RM bench press (8.8%) than the other two groups (17.6% and 18.0% for high and intermediate attendance, respectively). Conclusions Although there is not a direct correlation between training attendance and muscle strength gains, it is suggested that a minimum attendance of 80% is necessary to ensure optimal gains in upper body strength. PMID:23802051

  9. Association of Muscle Mass, Area, and Strength With Incident Diabetes in Older Adults: The Health ABC Study.

    PubMed

    Larsen, Britta A; Wassel, Christina L; Kritchevsky, Stephen B; Strotmeyer, Elsa S; Criqui, Michael H; Kanaya, Alka M; Fried, Linda F; Schwartz, Ann V; Harris, Tamara B; Ix, Joachim H

    2016-04-01

    The role of muscle in development of metabolic conditions is poorly understood. The authors show that, while there was no overall association between muscle mass, area, and strength and incident diabetes in older adults, more muscle at baseline was protective against incident diabetes for normal weight women. PMID:26930180

  10. Indoor mobility-related fatigue and muscle strength in nonagenarians: a prospective longitudinal study

    PubMed Central

    Ekmann, Anette; Thinggaard, Mikael; Christensen, Kaare; Avlund, Kirsten

    2014-01-01

    Background and aims Mobility-related fatigue is an important indicator of functional decline in old age, however, very little is known about fatigue in the oldest old population segment. The aim of this study was to examine the association between indoor mobility-related fatigue and muscle strength decline in nonagenarians. Methods The study is based on a prospective longitudinal study of all Danes born in 1905 and assessed in 1998, 2000 and 2003, and includes 92- to 93-year-old persons who were independent of help in basic indoor mobility at baseline (n = 1,353). Fatigue was assessed at baseline and defined as a subjective feeling of fatigue when transferring or walking indoors. The outcome measure, maximum grip strength, was measured at each measurement point. Results Grip strength declined throughout the study in participants with and without fatigue, but those reporting fatigue had significantly (P < .001) lower muscle strength during the entire study period. Longitudinal analyses indicated slightly slower decline in muscle strength among participants with fatigue compared to those without; however, observed selective dropout of participants with fatigue and poor performance at baseline needs to be considered when interpreting the results. Accordingly, participants without fatigue had significantly higher chances of being alive and having muscle strength above gender-specific median at first (RR 1.32, 95 % CI 1.07–1.58), second (RR 1.51, 1.06–1.96) and third (RR 1.39, 1.01–1.97) measurement points. Conclusions Indoor mobility-related fatigue in advanced later life should not merely be considered as an unpleasant symptom, but rather an indicator of physical impairment, and consequently declined physiological reserve. PMID:24297217

  11. Effects of Kinesio Tape application to quadriceps muscles on isokinetic muscle strength, gait, and functional parameters in patients with stroke.

    PubMed

    Ekiz, Timur; Aslan, Meryem Doğan; Özgirgin, Neşe

    2015-01-01

    The aim of this study was to evaluate the effects of Kinesio Tape (KT) application to quadriceps muscles on isokinetic muscle strength, gait, and functional parameters in patients with stroke. Twenty-four patients were allocated into KT and control groups. All patients participated in the same conventional rehabilitation program 5 times/wk for 4 wk. In addition, KT was applied to quadriceps muscles bilaterally to the patients in the KT group. Compared with baseline, peak torque levels increased significantly in both groups (all p < 0.05). However, change levels were significantly higher in the KT group than the control group at 60 degrees/second angular velocity (AV) in extension (p = 0.04) and 60 and 180 degrees/second AV in flexion (both p = 0.02) on the paretic side. Moreover, the change levels were more prominent in the KT group at 60 and 180 degrees/second AV in extension (p = 0.03 and p = 0.04, respectively) on the nonparetic side. Gait, balance, mobility, and quality of life values improved significantly in both groups (all p < 0.05), yet the change levels between the groups did not reach significance (p > 0.05). KT application to quadriceps muscles in addition to conventional exercises for 4 wk is effective on isokinetic but not functional parameters. PMID:26220179

  12. Test-retest reliability of innovated strength tests for hip muscles.

    PubMed

    Meyer, Christophe; Corten, Kristoff; Wesseling, Mariska; Peers, Koen; Simon, Jean-Pierre; Jonkers, Ilse; Desloovere, Kaat

    2013-01-01

    The burden of hip muscles weakness and its relation to other impairments has been well documented. It is therefore a pre-requisite to have a reliable method for clinical assessment of hip muscles function allowing the design and implementation of a proper strengthening program. Motor-driven dynamometry has been widely accepted as the gold-standard for lower limb muscle strength assessment but is mainly related to the knee joint. Studies focusing on the hip joint are less exhaustive and somewhat discrepant with regard to optimal participants position, consequently influencing outcome measures. Thus, we aimed to develop a standardized test setup for the assessment of hip muscles strength, i.e. flexors/extensors and abductors/adductors, with improved participant stability and to define its psychometric characteristics. Eighteen participants performed unilateral isokinetic and isometric contractions of the hip muscles in the sagittal and coronal plane at two separate occasions. Peak torque and normalized peak torque were measured for each contraction. Relative and absolute measures of reliability were calculated using the intraclass correlation coefficient and standard error of measurement, respectively. Results from this study revealed higher levels of between-day reliability of isokinetic/isometric hip abduction/flexion peak torque compared to existing literature. The least reliable measures were found for hip extension and adduction, which could be explained by a less efficient stabilization technique. Our study additionally provided a first set of reference normalized data which can be used in future research. PMID:24260550

  13. Side-Alternating Vibration Training for Balance and Ankle Muscle Strength in Untrained Women

    PubMed Central

    Spiliopoulou, Styliani I.; Amiridis, Ioannis G.; Tsigganos, Georgios; Hatzitaki, Vassilia

    2013-01-01

    Context: Side-alternating vibration (SAV) may help reduce the risk of falling by improving body balance control. Such training has been promoted as a strength-training intervention because it can increase muscle activation through an augmented excitatory input from the muscle spindles. Objective: To determine the effect of SAV training on static balance during 3 postural tasks of increasing difficulty and lower limb strength. Design: Randomized controlled clinical trial. Setting: Laboratory. Patients or Other Participants: A total of 21 healthy women were divided into training (n = 11; age = 43.35 ± 4.12 years, height = 169 ± 6.60 cm, mass = 68.33 ± 11.90 kg) and control (n = 10; age = 42.31 ± 3.73 years, height = 167 ± 4.32 cm, mass = 66.29 ± 10.74 kg) groups. Intervention(s): The training group completed a 9-week program during which participants performed 3 sessions per week of ten 15-second isometric contractions with a 30-second active rest of 3 exercises (half-squat, wide-stance squat, 1-legged half-squat) on an SAV plate (acceleration = 0.91–16.3g). The control group did not participate in any form of exercise over the 9-week period. Main Outcome Measure(s): We evaluated isokinetic and isometric strength of the knee extensors and flexors and ankle plantar flexors, dorsiflexors, and evertors. Static balance was assessed using 3 tasks of increasing difficulty (quiet bipedal stance, tandem stance, 1-legged stance). The electromyographic activity of the vastus lateralis, semitendinosus, medial gastrocnemius, tibialis anterior, and peroneus longus was recorded during postural task performance, baseline and pretraining, immediately posttraining, and 15 days posttraining. Results: After training in the training group, ankle muscle strength improved (P = .03), whereas knee muscle strength remained unaltered (P = .13). Improved ankle-evertor strength was observed at all angular velocities (P = .001). Postural sway decreased in both directions but was greater

  14. The relationship between femoral cartilage thickness and muscle strength in knee osteoarthritis.

    PubMed

    Tuna, Serpil; Balcı, Nilüfer; Özçakar, Levent

    2016-08-01

    To explore whether femoral cartilage thickness is related (and changes) with muscle strength in subjects with knee osteoarthritis (OA). Forty patients (27 F, 13 M) with knee OA-who were under quadriceps muscle strengthening program-were enrolled in the study. Isokinetic/isometric knee muscle strength measurements (at 30-60° angles and 60-180° velocity) were performed at baseline, end of the muscle strengthening program, and third month control visit using a biodex dynamometer. Femoral cartilage thicknesses (at medial/lateral condyle and intercondylar area) were measured using ultrasonography. Seventy-nine knees of 40 patients (27 F, 13 M) aged 52.03 ± 11.72 years (range, 26-71) were analyzed. Mean VAS scores on the first and third months were significantly lower than the initial values (p < 0.001, p = 0.049). Isometric peak torque and total work values at 180 °/s were significantly higher than the baseline measurements at first and third month controls (all p < 0.05). Cartilage thicknesses (at three sites) were significantly higher than the baseline measurements (all p < 0.05) on the third month but not on the first month (all p > 0.05). Femoral cartilage thicknesses were positively correlated with isometric strength values at baseline and third month. We propose that femoral cartilage thicknesses increase on the third month of strengthening therapy. Since this late-phase thickening parallels the earlier increase in muscle strength (starting, on the first month), we speculate that regeneration rather than edema might be the primary underlying cause. PMID:27091650

  15. Undercarboxylated osteocalcin, muscle strength and indices of bone health in older women.

    PubMed

    Levinger, Itamar; Scott, David; Nicholson, Geoffrey C; Stuart, Amanda L; Duque, Gustavo; McCorquodale, Thomas; Herrmann, Markus; Ebeling, Peter R; Sanders, Kerrie M

    2014-07-01

    We investigated the association between undercarboxylated osteocalcin (ucOC) and lower-limb muscle strength in women over the age of 70years. The study also aims to confirm the association between bone turnover markers and heel ultrasound measures. A post-hoc analysis using data collected as part of a randomized placebo-controlled trial of vitamin D supplementation. An immunoassay was used to quantify total OC (tOC), with hydroxyapatite pre-treatment for ucOC. We determined associations of absolute and relative (ucOC/tOC; ucOC%) measures of ucOC with lower-limb muscle strength, heel ultrasound measures of speed of sound (SOS) and broadband ultrasound attenuation (BUA), bone turnover markers (BTMs; P1NP and CTx) and the acute phase protein alpha-1-antichymotrypsin (α-ACT). ucOC%, but not absolute ucOC concentration, was positively associated with hip flexor, hip abductor and quadriceps muscle strength (all p<0.05). ucOC% was negatively associated with α-ACT (β-coefficient=-0.24, p=0.02). tOC was positively associated with both P1NP and CTx (p<0.001). For each per unit increase in tOC (μg/L) there was a corresponding lower BUA, SOS and SI (β-coefficient = -0.28; -0.23 and -0.23, respectively; all p<0.04). In conclusion, ucOC% is positively associated with muscle strength and negatively associated with α-ACT. These data support a role for ucOC in musculoskeletal interactions in humans. Whilst tOC is associated with bone health, ucOC% and ucOC may also be linked to falls and fracture risk by influencing muscle function. PMID:24662619

  16. Exercise effect on strength and range of motion of hand intrinsic muscles and joints.

    PubMed

    Less, M; Krewer, S E; Eickelberg, W W

    1977-08-01

    The intrinsic muscles of the hand are largely neglected in training, mainly because certain biomechanical principles must be applied in order for these muscles to be involved in hand exercises. Following these principles, a system of stretching and isometric exercises was developed. Twelve men exercised for four weeks, three times daily. Significant improvement in seven out of the 12 strength measurements was noted. Exercise seemed to affect just the metacarpophalangeal joints range of motion, while distal and proximal interphalangeal joints remained largely unaffected. PMID:880015

  17. Characteristics of Body Composition and Muscle Strength of North Korean Refugees during South Korean Stay

    PubMed Central

    Cho, Sun Wook; Koh, Eun Sil; Kim, Si Eun; Kim, Seok Joong

    2015-01-01

    Background The aim of this study was to investigate the changes of body composition and muscle strength of North Korean refugees (NKRs) according to their duration of stay in South Korea. Methods NKRs who volunteered and were living in South Korea, aged 20 to 75 years were recruited. Body compositions were analyzed by bioelectrical impedance analysis. Muscle strength was measured with the hand grip test. Demographic and migration information was obtained with a questionnaire. Results A total of 158 volunteers were recruited at a mean age of 48.3±11.4 years. The mean time from when they escaped from North Korea and arrived in South Korea was 5.8±4.3 years. Height, weight, and body surface area were significantly smaller in all NKRs compared to South Korean controls, except for women aged over 50 years. In females of younger ages (<50 years), NKRs with more than a 4-year stay in South Korea had a higher weight and fat mass than that of those who had a shorter stay (less than 4 years) in South Korea. All NKRs had a weaker grip strength than that of the age-matched controls from South Korea. Conclusion The NKRs showed relatively smaller physiques and weaker muscle strength than that of the South Korean controls. In younger female NKRs, shorter South Korean stay group showed small body weight and fat mass than that of longer South Korean stay group. Specific health support programs might be needed. PMID:26485471

  18. Muscle Strength, Physical Activity, and Functional Limitations in Older Adults with Central Obesity

    PubMed Central

    Germain, Cassandra M.; Batsis, John A.; Vasquez, Elizabeth; McQuoid, Douglas R.

    2016-01-01

    Background. Obesity and muscle weakness are independently associated with increased risk of physical and functional impairment in older adults. It is unknown whether physical activity (PA) and muscle strength combined provide added protection against functional impairment. This study examines the association between muscle strength, PA, and functional outcomes in older adults with central obesity. Methods. Prevalence and odds of physical (PL), ADL, and IADL limitation were calculated for 6,388 community dwelling adults aged ≥ 60 with central obesity. Individuals were stratified by sex-specific hand grip tertiles and PA. Logistic models were adjusted for age, education, comorbidities, and body-mass index and weighted. Results. Overall prevalence of PL and ADL and IADL limitations were progressively lower by grip category. Within grip categories, prevalence was lower for individuals who were active than those who were inactive. Adjusted models showed significantly lower odds of PL OR 0.42 [0.31, 0.56]; ADL OR 0.60 [0.43, 0.84], and IADL OR 0.46 [0.35, 0.61] for those in the highest grip strength category as compared to those in the lowest grip category. Conclusion. Improving grip strength in obese elders who are not able to engage in traditional exercise is important for reducing odds of physical and functional impairment. PMID:27034833

  19. Effects of Vibration Training and Detraining on Balance and Muscle Strength in Older Adults

    PubMed Central

    Marín, Pedro J.; Martín-López, Aurora; Vicente-Campos, Davinia; Angulo-Carrere, MT; García-Pastor, Teresa; Garatachea, Nuria; Chicharro, José L.

    2011-01-01

    The purpose of this study was to analyze the effects of 2 days/week versus 4 days/week of Whole Body Vibration (WBV) during eight weeks of WBV training on health-related quality of life (SF-36), balance and lower body strength, as well as short-term detraining (3 weeks) on balance and lower body strength among older adults. Thirty-four older adults were randomly assigned to a control group (Control; n = 11) or to one of the vibration training groups: WBV 2 days/week (WBV_2d; n = 11) or WBV 4 days/week (WBV_4d; n = 12). The WBV groups exercised for 8 weeks, following 3 weeks of detraining. Lower body strength increased significantly (p < 0.05) for both groups, WBV_2d and WBV_4d, after 8-week training. A significant reduction in strength was observed following 3 weeks of detraining only in WBV_2d group (p < 0.05). All variables of the SF-36 and the balance test did not change after intervention in any group. 2 days/week and 4 days/week of WBV during 8 weeks showed the same improvements on muscle strength. 3 weeks of detraining did not reverse the gains in strength made during 32 sessions of WBV. Key points 2 days and 4 days per week of WBV training during 8 weeks showed the same improvements on muscle strength. 3 weeks of detraining did not reverse the gains in strength made during 32 sessions of WBV exercise. 3 weeks of detraining did reverse the gains in strength made during 16 sessions of WBV exercise. PMID:24150633

  20. Influence of recreational activity and muscle strength on ulnar bending stiffness in men

    NASA Technical Reports Server (NTRS)

    Myburgh, K. H.; Charette, S.; Zhou, L.; Steele, C. R.; Arnaud, S.; Marcus, R.

    1993-01-01

    Bone bending stiffness (modulus of elasticity [E] x moment of inertia [I]), a measure of bone strength, is related to its mineral content (BMC) and geometry and may be influenced by exercise. We evaluated the relationship of habitual recreational exercise and muscle strength to ulnar EI, width, and BMC in 51 healthy men, 28-61 yr of age. BMC and width were measured by single photon absorptiometry and EI by mechanical resistance tissue analysis. Maximum biceps strength was determined dynamically (1-RM) and grip strength isometrically. Subjects were classified as sedentary (S) (N = 13), moderately (M) (N = 18), or highly active (H) (N = 20) and exercised 0.2 +/- 0.2; 2.2 +/- 1.3; and 6.8 +/- 2.3 h.wk-1 (P < 0.001). H had greater biceps (P < 0.0005) and grip strength (P < 0.05), ulnar BMC (P < 0.05), and ulnar EI (P = 0.01) than M or S, who were similar. Amount of activity correlated with grip and biceps strength (r = 0.47 and 0.49; P < 0.001), but not with bone measurements, whereas muscle strength correlated with both EI and BMC (r = 0.40-0.52, P < 0.005). EI also correlated significantly with both BMC and ulnar width (P < 0.0001). Ulnar width and biceps strength were the only independent predictors of EI (r2 = 0.67, P < 0.0001). We conclude that levels of physical activity sufficient to increase arm strength influence ulnar bending stiffness.

  1. Angiotensin-Converting Enzyme Genotype Affects Skeletal Muscle Strength In Elite Athletes

    PubMed Central

    Costa, Aldo Matos; Silva, António José; Garrido, Nuno; Louro, Hugo; Marinho, Daniel Almeida; Cardoso Marques, Mário; Breitenfeld, Luiza

    2009-01-01

    Previous studies have associated angiotensin-converting enzyme (ACE) D allele with variability in the skeletal muscle baseline strength, though conclusions have been inconsistent across investigations. The purpose of this study was to examine the possible association between ACE genotype and skeletal muscle baseline strength in elite male and female athletes involved in different event expertise. A group of 58 elite athletes, designated as Olympic candidates, were studied: 35 swimmers (19 males and 16 females, 18.8 ± 3.2 years) and 23 triathletes (15 males and 8 females, 18.7 ± 3.0 years). The athletes were classified as: short (≤ 200m) and middle (400m to 1500m) distance athletes, respectively. For each subject the grip strength in both hands was measure using an adjustable mechanical hand dynamometer. The maximum height in both squat jump (SJ) and counter movement jump (CMJ) were also assessed, using a trigonometric carpet (Ergojump Digitime 1000; Digitest, Jyvaskyla, Finland). DNA extraction was obtained with Chelex 100® and genotype determination by PCR-RFLP methods. Both males and females showed significantly higher right grip strength in D allele carriers compared to II homozygote’s. We found that allelic frequency differs significantly by event distance specialization in both genders (p < 0.05). In fact, sprinter D allele carriers showed the superior scores in nearly all strength measurements (p < 0.05), in both genders. Among endurance athletes, the results also demonstrated that female D allele carriers exhibited the higher performance right grip and CMJ scores (p < 0.05). In conclusion, the ACE D allele seems associated with skeletal muscle baseline strength in elite athletes, being easily identified in females. Key points DD homozygote’s and D allele carriers from both genders shows significantly higher right grip strength. Right grip strength remains significantly higher in the D allele carrier’s female endurance group. Female’s D allele

  2. Apple Pomace Extract Improves Endurance in Exercise Performance by Increasing Strength and Weight of Skeletal Muscle.

    PubMed

    Jeong, Ji-Woong; Shim, Jae-Jung; Choi, Il-Dong; Kim, Sung-Hwan; Ra, Jehyeon; Ku, Hyung Keun; Lee, Dong Eun; Kim, Tae-Youl; Jeung, Woonhee; Lee, Jung-Hee; Lee, Ki Won; Huh, Chul-Sung; Sim, Jae-Hun; Ahn, Young-Tae

    2015-12-01

    Ursolic acid is a lipophilic pentacyclic triterpenoid found in many fruits and herbs and is used in several herbal folk medicines for diabetes. In this study, we evaluated the effects of apple pomace extract (APE; ursolic acid content, 183 mg/g) on skeletal muscle atrophy. To examine APE therapeutic potential in muscle atrophy, we investigated APE effects on the expression of biomarkers associated with muscle atrophy and hypertrophy. We found that APE inhibited atrophy, while inducing hypertrophy in C2C12 myotubes by decreasing the expression of atrophy-related genes and increasing the expression of hypertrophy-associated genes. The in vivo experiments using mice fed a diet with or without APE showed that APE intake increased skeletal muscle mass, as well as grip strength and exercise capacity. In addition, APE significantly improved endurance in the mice, as evidenced by increased exhaustive running time and muscle weight, and reduced the expression of the genes involved in the development of muscle atrophy. APE also decreased the concentration of serum lactate and lactate dehydrogenase, inorganic phosphate, and creatinine, the indicators of accumulated fatigue and exercise-induced stress. These results suggest that APE may be useful as an ergogenic functional food or dietary supplement. PMID:26331671

  3. A Randomized Trial on the Effect of Bone Tissue on Vibration-induced Muscle Strength Gain and Vibration-induced Reflex Muscle Activity

    PubMed Central

    Cidem, Muharrem; Karacan, İlhan; Diraçoğlu, Demirhan; Yıldız, Aysel; Küçük, Suat Hayri; Uludağ, Murat; Gün, Kerem; Özkaya, Murat; Karamehmetoğlu, Şafak Sahir

    2014-01-01

    Background: Whole-body vibration (WBV) induces reflex muscle activity and leads to increased muscle strength. However, little is known about the physiological mechanisms underlying the effects of whole-body vibration on muscular performance. Tonic vibration reflex is the most commonly cited mechanism to explain the effects of whole-body vibration on muscular performance, although there is no conclusive evidence that tonic vibration reflex occurs. The bone myoregulation reflex is another neurological mechanism used to explain the effects of vibration on muscular performance. Bone myoregulation reflex is defined as a reflex mechanism in which osteocytes exposed to cyclic mechanical loading induce muscle activity. Aims: The aim of this study was to assess whether bone tissue affected vibration-induced reflex muscle activity and vibration-induced muscle strength gain. Study Design: A prospective, randomised, controlled, double-blind, parallel-group clinical trial. Methods: Thirty-four participants were randomised into two groups. High-magnitude whole-body vibration was applied in the exercise group, whereas low-magnitude whole-body vibration exercises were applied in the control group throughout 20 sessions. Hip bone mineral density, isokinetic muscle strength, and plasma sclerostin levels were measured. The surface electromyography data were processed to obtain the Root Mean Squares, which were normalised by maximal voluntarily contraction. Results: In the exercise group, muscle strength increased in the right and left knee flexors (23.9%, p=0.004 and 27.5%, p<0.0001, respectively). However, no significant change was observed in the knee extensor muscle strength. There was no significant change in the knee muscle strength in the control group. The vibration-induced corrected Root Mean Squares of the semitendinosus muscle was decreased by 2.8 times (p=0.005) in the exercise group, whereas there was no change in the control group. Sclerostin index was decreased by 15

  4. Quantitative muscle strength testing: a comparison of job strength requirements and actual worker strength among military technicians.

    PubMed

    Pedersen, D M; Clark, J A; Johns, R E; White, G L; Hoffman, S

    1989-01-01

    In this study the authors investigate the percentage of mismatch between job demands and worker physical capacity in Utah National Guard mechanics. This population had demonstrated a higher incidence of low back trouble than other job descriptions reviewed. The authors utilized onsite still and videotape photography and a computerized biomechanical strength prediction model to assess loads on the lumbosacral spine due to various job tasks. Job demands were then compared to the actual physical capacity of the individual workers based on static strength testing in job-related positions. A load cell on the testing apparatus entered the force generated into a computer which averaged the force of the last three seconds of a five-second lift. It was determined that as much as a 38% mismatch existed within this population for some job tasks which these workers were exposed to. Suggestions for preventing job-related low back cumulative trauma disorders are presented, including: engineering redesign, worker selection programs, work hardening, and others. PMID:2522169

  5. Multimedia-Based Therapy Model for Non-Pharmacological Stroke with Decrease Impaired Muscle Strength

    NASA Astrophysics Data System (ADS)

    Hajar Puji Sejati, Rr; Muhimmah, Izzati; Mahtarami, Affan

    2016-01-01

    Stroke patients who experience a decrease in muscle strength need to do exercises so that they can increase their muscle strength. In order to enable the patient does exercise independently the multimedia-based stroke therapy model is needed. These exercises can be done independently, with supervision of the family member at home. So, we develop prototype of the multimedia-based therapy for the family member so that they can assist patients performing exercises without attending therapy session in hospital. This model was built according to the advices from physiotherapist and a medical rehabilitation doctor. This model has been evaluated through focused group discussion by physiotherapists. And they gave positive responses to this proposed model.

  6. Behavioural changes and muscle strength in Rattus norvegicus experimentally infected with Toxocara cati and T. canis.

    PubMed

    Santos, S V; Moura, J V L; Lescano, S A Z; Castro, J M; Ribeiro, M C S A; Chieffi, P P

    2015-07-01

    Toxocara canis and Toxocara cati are nematode parasites in dogs and cats, respectively, transmitted by ingestion of embryonated eggs, transmammary and transplacental (T. canis) routes and paratenic host predation. Many parasites use mechanisms that change the behaviour of their hosts to ensure continued transmission. Several researchers have demonstrated behavioural changes in mouse models as paratenic hosts for T. canis. However, there have been no studies on behavioural changes in laboratory rats (Rattus norvegicus) experimentally infected with T. cati. This study investigated behavioural changes and muscle strength in male and female rats experimentally infected with T. cati or T. canis in acute and chronic phases of infection. Regardless of sex, rats infected with T. cati showed a greater decrease in muscle strength 42 days post infection compared to rats infected with T. canis. However, behavioural changes were only observed in female rats infected with T. canis. PMID:24725503

  7. Improved Knee Extensor Strength with Resistance Training Associates with Muscle Specific miRNAs in Older Adults

    PubMed Central

    Zhang, Tan; Birbrair, Alexander; Wang, Zhong-Min; Messi, María L.; Marsh, Anthony P.; Leng, Iris; Nicklas, Barbara J.; Delbono, Osvaldo

    2015-01-01

    Regular exercise, particularly resistance training (RT), is the only therapy known to consistently improve muscle strength and quality (force per unit of mass) in older persons, but there is considerable variability in responsiveness to training. Identifying sensitive diagnostic biomarkers of responsiveness to RT may inform the design of a more efficient exercise regimen to improve muscle strength in older adults. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression. We quantified six muscle specific miRNAs (miR-1, -133a, -133b, -206, -208b and -499) in both muscle tissue and blood plasma, and their relationship with knee extensor strength in seven older (age = 70.5 ± 2.5 years) adults before and after 5 months of RT. MiRNAs differentially responded to RT; muscle miR-133b decreased, while all plasma miRNAs tended to increase. Percent changes in knee extensor strength with RT showed strong positive correlations with percent changes in muscle miR-133a, -133b, -206 and with percent changes in plasma and plasma/muscle miR-499 ratio. Baseline level of plasma or plasma/muscle miR-499 ratio further predicts muscle response to RT, while changes in muscle miR-133a, -133b, -206 may correlate with muscle TNNT1gene alternative splicing in response to RT. Our results indicate that RT alters muscle specific miRNAs in muscle and plasma, and that these changes account for some of the variation in strength responses to RT in older adults. PMID:25560803

  8. Muscle Strength Enhancement Following Home-Based Virtual Cycling Training in Ambulatory Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Chen, Chia-Ling; Hong, Wei-Hsien; Cheng, Hsin-Yi Kathy; Liaw, Mei-Yun; Chung, Chia-Ying; Chen, Chung-Yao

    2012-01-01

    This study is the first well-designed randomized controlled trial to assess the effects of a novel home-based virtual cycling training (hVCT) program for improving muscle strength in children with spastic cerebral palsy (CP). Twenty-eight ambulatory children with spastic CP aged 6-12 years were randomly assigned to an hVCT group (n = 13) or a…

  9. Ischemic preconditioning increases muscle perfusion, oxygen uptake, and force in strength-trained athletes.

    PubMed

    Paradis-Deschênes, Pénélope; Joanisse, Denis R; Billaut, François

    2016-09-01

    Muscle ischemia and reperfusion induced by ischemic preconditioning (IPC) can improve performance in various activities. However, the underlying mechanisms are still poorly understood. The purpose of this study was to examine the effects of IPC on muscle hemodynamics and oxygen (O2) uptake during repeated maximal contractions. In a cross-over, randomized, single-blind study, 10 strength-trained men performed 5 sets of 5 maximal voluntary knee extensions of the right leg on an isokinetic dynamometer, preceded by either IPC of the right lower limb (3×5-min compression/5-min reperfusion cycles at 200 mm Hg) or sham (20 mm Hg). Changes in deoxyhemoglobin, expressed as a percentage of arterial occlusion, and total hemoglobin ([THb]) concentrations of the vastus lateralis muscle were monitored continuously by near-infrared spectroscopy. Differences between IPC and sham were analyzed using Cohen's effect size (ES) ± 90% confidence limits, and magnitude-based inferences. Compared with sham, IPC likely increased muscle blood volume at rest (↑[THb], 46.5%; ES, 0.56; 90% confidence limits for ES, -0.21, 1.32). During exercise, peak force was almost certainly higher (11.8%; ES, 0.37; 0.27, 0.47), average force was very likely higher (12.6%; ES, 0.47; 0.29, 0.66), and average muscle O2 uptake was possibly increased (15.8%; ES, 0.36; -0.07, 0.79) after IPC. In the recovery periods between contractions, IPC also increased blood volume after sets 1 (23.6%; ES, 0.30; -0.05, 0.65) and 5 (25.1%; ES, 0.32; 0.09, 0.55). Three cycles of IPC immediately increased muscle perfusion and O2 uptake, conducive to higher repeated force capacity in strength-trained athletes. This maneuver therefore appears relevant to enhancing exercise training stimulus. PMID:27574913

  10. Respiratory muscle and pulmonary function in polymyositis and other proximal myopathies.

    PubMed Central

    Braun, N M; Arora, N S; Rochester, D F

    1983-01-01

    We studied 53 patients with proximal myopathy to determine at what level of muscle weakness hypercapnic respiratory failure is likely, and which tests of pulmonary function or respiratory muscle strength would best suggest this development. Respiratory muscle strength was determined from maximal static efforts and in half the patients, both inspiratory and expiratory muscle strengths were less than 50% of normal. In the 37 patients without lung disease respiratory muscle weakness was accompanied by significant decreases in vital capacity, total lung capacity, and maximum voluntary ventilation; by significant increases in residual volume and arterial carbon dioxide tension (PaCO2); and greater likelihood of dependence on ventilators, atelectasis, and pneumonia. Hypercapnia was particularly likely when respiratory muscle strength was less than 30% of normal in uncomplicated myopathy, and when vital capacity was less than 55% of the predicted value in any patient. PMID:6412385

  11. Effects of Egg White Protein Supplementation on Muscle Strength and Serum Free Amino Acid Concentrations

    PubMed Central

    Hida, Azumi; Hasegawa, Yuko; Mekata, Yuko; Usuda, Mika; Masuda, Yasunobu; Kawano, Hitoshi; Kawano, Yukari

    2012-01-01

    The aim of this study was to evaluate the effects of egg white protein compared to carbohydrate intake prior to exercise on fat free mass (FFM), one repetition maximum (1RM) muscle strength and blood biochemistry in female athletes. Thirty healthy female collegiate athletes were recruited for this study and matched by sport type, body fat percentage and 1RM leg curl muscle strength. Participants were randomly divided into two groups: protein group (15.0 g egg white protein; 75 kcal) and carbohydrate group (17.5 g maltodextrin, 78 kcal). Supplements were administered daily at the same time in a double-blind manner prior to training during an 8-week period. Measurements were performed before and after the 8-week regimen. The mean dietary energy intake did not change throughout the study period. FFM and 1RM assessments (i.e., leg curl, leg extension, squat, and bench press) increased in both groups. Furthermore, serum urea and serum citrulline levels after the 8-week regimen increased significantly only in the protein group. Our findings indicated that compared to the carbohydrate supplement, the protein supplement was associated with some changes in protein metabolites but not with changes in body composition or muscle strength. PMID:23201768

  12. The effect of protein timing on muscle strength and hypertrophy: a meta-analysis

    PubMed Central

    2013-01-01

    Protein timing is a popular dietary strategy designed to optimize the adaptive response to exercise. The strategy involves consuming protein in and around a training session in an effort to facilitate muscular repair and remodeling, and thereby enhance post-exercise strength- and hypertrophy-related adaptations. Despite the apparent biological plausibility of the strategy, however, the effectiveness of protein timing in chronic training studies has been decidedly mixed. The purpose of this paper therefore was to conduct a multi-level meta-regression of randomized controlled trials to determine whether protein timing is a viable strategy for enhancing post-exercise muscular adaptations. The strength analysis comprised 478 subjects and 96 ESs, nested within 41 treatment or control groups and 20 studies. The hypertrophy analysis comprised 525 subjects and 132 ESs, nested with 47 treatment or control groups and 23 studies. A simple pooled analysis of protein timing without controlling for covariates showed a small to moderate effect on muscle hypertrophy with no significant effect found on muscle strength. In the full meta-regression model controlling for all covariates, however, no significant differences were found between treatment and control for strength or hypertrophy. The reduced model was not significantly different from the full model for either strength or hypertrophy. With respect to hypertrophy, total protein intake was the strongest predictor of ES magnitude. These results refute the commonly held belief that the timing of protein intake in and around a training session is critical to muscular adaptations and indicate that consuming adequate protein in combination with resistance exercise is the key factor for maximizing muscle protein accretion. PMID:24299050

  13. The power of the mind: the cortex as a critical determinant of muscle strength/weakness.

    PubMed

    Clark, Brian C; Mahato, Niladri K; Nakazawa, Masato; Law, Timothy D; Thomas, James S

    2014-12-15

    We tested the hypothesis that the nervous system, and the cortex in particular, is a critical determinant of muscle strength/weakness and that a high level of corticospinal inhibition is an important neurophysiological factor regulating force generation. A group of healthy individuals underwent 4 wk of wrist-hand immobilization to induce weakness. Another group also underwent 4 wk of immobilization, but they also performed mental imagery of strong muscle contractions 5 days/wk. Mental imagery has been shown to activate several cortical areas that are involved with actual motor behaviors, including premotor and M1 regions. A control group, who underwent no interventions, also participated in this study. Before, immediately after, and 1 wk following immobilization, we measured wrist flexor strength, voluntary activation (VA), and the cortical silent period (SP; a measure that reflect corticospinal inhibition quantified via transcranial magnetic stimulation). Immobilization decreased strength 45.1 ± 5.0%, impaired VA 23.2 ± 5.8%, and prolonged the SP 13.5 ± 2.6%. Mental imagery training, however, attenuated the loss of strength and VA by ∼50% (23.8 ± 5.6% and 12.9 ± 3.2% reductions, respectively) and eliminated prolongation of the SP (4.8 ± 2.8% reduction). Significant associations were observed between the changes in muscle strength and VA (r = 0.56) and SP (r = -0.39). These findings suggest neurological mechanisms, most likely at the cortical level, contribute significantly to disuse-induced weakness, and that regular activation of the cortical regions via imagery attenuates weakness and VA by maintaining normal levels of inhibition. PMID:25274345

  14. Vitamin D: A Review on Its Effects on Muscle Strength, the Risk of Fall, and Frailty

    PubMed Central

    Halfon, Matthieu; Phan, Olivier; Teta, Daniel

    2015-01-01

    Vitamin D is the main hormone of bone metabolism. However, the ubiquitary nature of vitamin D receptor (VDR) suggests potential for widespread effects, which has led to new research exploring the effects of vitamin D on a variety of tissues, especially in the skeletal muscle. In vitro studies have shown that the active form of vitamin D, calcitriol, acts in myocytes through genomic effects involving VDR activation in the cell nucleus to drive cellular differentiation and proliferation. A putative transmembrane receptor may be responsible for nongenomic effects leading to rapid influx of calcium within muscle cells. Hypovitaminosis D is consistently associated with decrease in muscle function and performance and increase in disability. On the contrary, vitamin D supplementation has been shown to improve muscle strength and gait in different settings, especially in elderly patients. Despite some controversies in the interpretation of meta-analysis, a reduced risk of falls has been attributed to vitamin D supplementation due to direct effects on muscle cells. Finally, a low vitamin D status is consistently associated with the frail phenotype. This is why many authorities recommend vitamin D supplementation in the frail patient. PMID:26000306

  15. Live strong and prosper: the importance of skeletal muscle strength for healthy ageing.

    PubMed

    McLeod, Michael; Breen, Leigh; Hamilton, D Lee; Philp, Andrew

    2016-06-01

    Due to improved health care, diet and infrastructure in developed countries, since 1840 life expectancy has increased by approximately 2 years per decade. Accordingly, by 2050, a quarter of Europe's population will be over 65 years, representing a 10 % rise in half a century. With this rapid rise comes an increased prevalence of diseases of ageing and associated healthcare expenditure. To address the health consequences of global ageing, research in model systems (worms, flies and mice) has indicated that reducing the rate of organ growth, via reductions in protein synthetic rates, has multi-organ health benefits that collectively lead to improvements in lifespan. In contrast, human pre-clinical, clinical and large cohort prospective studies demonstrate that ageing leads to anabolic (i.e. growth) impairments in skeletal muscle, which in turn leads to reductions in muscle mass and strength, factors directly associated with mortality rates in the elderly. As such, increasing muscle protein synthesis via exercise or protein-based nutrition maintains a strong, healthy muscle mass, which in turn leads to improved health, independence and functionality. The aim of this review is to critique current literature relating to the maintenance of muscle mass across lifespan and discuss whether maintaining or reducing protein synthesis is the most logical approach to support musculoskeletal function and by extension healthy human ageing. PMID:26791164

  16. Relationships between Isometric Muscle Strength, Gait Parameters, and Gross Motor Function Measure in Patients with Cerebral Palsy

    PubMed Central

    Shin, Hyung-Ik; Sung, Ki Hyuk; Chung, Chin Youb; Lee, Kyoung Min; Lee, Seung Yeol; Lee, In Hyeok

    2016-01-01

    Purpose This study investigated the correlation between isometric muscle strength, gross motor function, and gait parameters in patients with spastic cerebral palsy and to find which muscle groups play an important role for gait pattern in a flexed knee gait. Materials and Methods Twenty-four ambulatory patients (mean age, 10.0 years) with spastic cerebral palsy who were scheduled for single event multilevel surgery, including distal hamstring lengthening, were included. Preoperatively, peak isometric muscle strength was measured for the hip flexor, hip extensor, knee flexor, and knee extensor muscle groups using a handheld dynamometer, and three-dimensional (3D) gait analysis and gross motor function measure (GMFM) scoring were also performed. Correlations between peak isometric strength and GMFM, gait kinematics, and gait kinetics were analyzed. Results Peak isometric muscle strength of all muscle groups was not related to the GMFM score and the gross motor function classification system level. Peak isometric strength of the hip extensor and knee extensor was significantly correlated with the mean pelvic tilt (r=-0.588, p=0.003 and r=-0.436, p=0.033) and maximum pelvic obliquity (r=-0.450, p=0.031 and r=-0.419, p=0.041). There were significant correlations between peak isometric strength of the knee extensor and peak knee extensor moment in early stance (r=0.467, p=0.021) and in terminal stance (r=0.416, p=0.043). Conclusion There is no correlation between muscle strength and gross motor function. However, this study showed that muscle strength, especially of the extensor muscle group of the hip and knee joints, might play a critical role in gait by stabilizing pelvic motion and decreasing energy consumption in a flexed knee gait. PMID:26632404

  17. Lower extremity muscle function after strength or power training in older adults.

    PubMed

    Marsh, Anthony P; Miller, Michael E; Rejeski, W Jack; Hutton, Stacy L; Kritchevsky, Stephen B

    2009-10-01

    It is unclear whether strength training (ST) or power training (PT) is the more effective intervention at improving muscle strength and power and physical function in older adults. The authors compared the effects of lower extremity PT with those of ST on muscle strength and power in 45 older adults (74.8 +/- 5.7 yr) with self-reported difficulty in common daily activities. Participants were randomized to 1 of 3 treatment groups: PT, ST, or wait-list control. PT and ST trained 3 times/wk for 12 wk using knee-extension (KE) and leg-press (LP) machines at approximately 70% of 1-repetition maximum (1RM). For PT, the concentric phase of the KE and LP was completed "as fast as possible," whereas for ST the concentric phase was 2-3 s. Both PT and ST paused briefly at the midpoint of the movement and completed the eccentric phase of the movement in 2-3 s. PT and ST groups showed significant improvements in KE and LP 1RM compared with the control group. Maximum KE and LP power increased approximately twofold in PT compared with ST. At 12 wk, compared with control, maximum KE and LP power were significantly increased for the PT group but not for the ST group. In older adults with compromised function, PT leads to similar increases in strength and larger increases in power than ST. PMID:19940322

  18. Muscle Activation and Performance During Trunk Strength Testing in High-Level Female and Male Football Players.

    PubMed

    Roth, Ralf; Donath, Lars; Zahner, Lukas; Faude, Oliver

    2016-06-01

    For performance and injury prevention in sport, core strength and endurance are focused prerequisites. Therefore we evaluated characteristics of trunk muscle activation and performance during strength-endurance related trunk field tests. Strength-endurance ability, as total time to failure, and activation of trunk muscles was measured in 39 football players of the highest German female football league (Bundesliga) (N = 18, age: 20.7 y [SD 4.4]) and the highest national male under-19 league (N = 21, age: 17.9 y [0.7]) in prone plank, side plank, and dorsal position. Maximal isometric force was assessed during trunk extension and flexion, rotation, and lateral flexion to normalize EMG and to compare with the results of strength-endurance tests. For all positions of endurance strength tests, a continuous increase in normalized EMG activation was observed (P < .001). Muscle activation of the rectus abdominis and external oblique in prone plank position exceeded the maximal voluntary isometric contraction activation, with a significantly higher activation in females (P = .02). We conclude, that in the applied strength-endurance testing, the activation of trunk muscles was high, especially in females. As high trunk muscle activation can infer fatigue, limb strength can limit performance in prone and side plank position, particularly during high trunk muscle activation. PMID:26671894

  19. Effects of whole body vibration training on body composition, skeletal muscle strength, and cardiovascular health

    PubMed Central

    Park, Song-Young; Son, Won-Mok; Kwon, Oh-Sung

    2015-01-01

    Whole body vibration training (WBVT) has been used as a supplement to conventional exercise training such as resistance exercise training to improve skeletal muscle strength, specifically, in rehabilitation field. Recently, this exercise modality has been utilized by cardiovascular studies to examine whether WBVT can be a useful exercise modality to improve cardiovascular health. These studies reported that WBVT has not only beneficial effects on muscular strength but also cardiovascular health in elderly and disease population. However, its mechanism underlying the beneficial effects of WBVT in cardiovascular health has not been well documented. Therefore, this review highlighted the impacts of WBVT on cardiovascular health, and its mechanisms in conjunction with the improved muscular strength and body composition in various populations. PMID:26730378

  20. p75NTR-mediated signaling promotes the survival of myoblasts and influences muscle strength.

    PubMed

    Reddypalli, Shailaja; Roll, Kristin; Lee, Hyung-Kook; Lundell, Martha; Barea-Rodriguez, Edwin; Wheeler, Esther F

    2005-09-01

    During muscle development, the p75(NTR) is expressed transiently on myoblasts. The temporal expression pattern of the receptor raises the possibility that the receptor is influencing muscle development. To test this hypothesis, p75(NTR)-deficient mutant mice were tested for muscle strength by using a standard wire gripe strength test and were found to have significantly decreased strength relative to that of normal mice. When normal mybolasts were examined in vivo for expression of NGF receptors, p75(NTR) was detected on myoblasts but the high affinity NGF receptor, trk A, was not co-expressed with p75(NTR). In vitro, proliferating C2C12 and primary myoblasts co-expressed the p75(NTR) and MyoD, but immunofluorescent analysis of primary myoblasts and RT-PCR analysis of C2C12 mRNA revealed that myoblasts were devoid of trk A. In contrast to the cell death functions that characterize the p75(NTR) in neurons, p75(NTR)-positive primary and C2C12 myoblasts did not differentiate or undergo apoptosis in response to neurotrophins. Rather, myoblasts survived and even proliferated when grown at subconfluent densities in the presence of the neurotrophins. Furthermore, when myoblasts treated with NGF were lysed and immunoprecipitated with antibodies against phosphorylated I-kappaB and AKT, the cells contained increased levels of both phospho-proteins, both of which promote cell survival. By contrast, neurotrophin-treated myoblasts did not induce phosphorylation of Map Kinase p42/44 or p38, indicating the survival was not mediated by the trk A receptor. Taken together, the data indicate that the p75(NTR) mediates survival of myoblasts prior to differentiation and that the activity of this receptor during myogenesis is important for developing muscle. PMID:15754321

  1. CNTF 1357 G → A polymorphism and the muscle strength response to resistance training

    PubMed Central

    Walsh, Sean; Kelsey, Bethany K.; Angelopoulos, Theodore J.; Clarkson, Priscilla M.; Gordon, Paul M.; Moyna, Niall M.; Visich, Paul S.; Zoeller, Robert F.; Seip, Richard L.; Bilbie, Steve; Thompson, Paul D.; Hoffman, Eric P.; Price, Thomas B.; Devaney, Joseph M.

    2009-01-01

    The present study examined associations between the ciliary neurotrophic factor (CNTF) 1357 G → A polymorphism and the muscle strength response to a unilateral, upper arm resistance-training (RT) program among healthy, young adults. Subjects were 754 Caucasian men (40%) and women (60%) who were genotyped and performed a training program of the nondominant (trained) arm with the dominant (untrained) arm as a comparison. Peak elbow flexor strength was measured with one repetition maximum, isometric strength with maximum voluntary contraction, and bicep cross-sectional area with MRI in the trained and untrained arms before and after training. Women with the CNTF GG genotype gained more absolute isometric strength, as measured by MVC (6.5 ± 0.3 vs. 5.2 ± 0.5 kg), than carriers of the CNTF A1357 allele in the trained arm pre- to posttraining (P < 0.05). No significant associations were seen in men. Women with the CNTF GG genotype gained more absolute dynamic (1.0 ± 0.1 vs. 0.6 ± 0.1 kg) and allometric (0.022 ± 0.0 vs. 0.015 ± 0.0 kg/kg−0.67) strength, as measured by 1 RM, than carriers of the CNTF A1357 allele in the untrained arm pre- to posttraining (P < 0.05). No significant associations were seen in men. No significant associations, as measured by cross-sectional area, were seen in men or women. The CNTF 1357 G → A polymorphism explains only a small portion of the variability in the muscle strength response to training in women. PMID:19628720

  2. The effects of gluteus muscle strengthening exercise and lumbar stabilization exercise on lumbar muscle strength and balance in chronic low back pain patients

    PubMed Central

    Jeong, Ui-Cheol; Sim, Jae-Heon; Kim, Cheol-Yong; Hwang-Bo, Gak; Nam, Chan-Woo

    2015-01-01

    [Purpose] The aim of this study was to examine the effects of exercise to strengthen the muscles of the hip together with lumbar segmental stabilization exercise on the lumbar disability index, lumbar muscle strength, and balance. [Subjects and Methods] This study randomly and equally assigned 40 participants who provided written consent to participate in this study to a lumbar segmental stabilization exercise plus exercise to strengthen the muscles of the gluteus group (SMG + LES group) and a lumbar segmental stabilization exercise group. [Results] Each evaluation item showed a statistically significant effect. [Conclusion] Clinical application of exercise in this study showed that lumbar segmental stabilization exercise plus exercise to strengthen the muscles of the gluteus resulted in a greater decrease in low back pain disability index and increase in lumbar muscle strength and balance ability than lumbar segmental stabilization exercise in chronic low back pain patients receiving the exercise treatments during the same period. PMID:26834359

  3. Discharge properties and recruitment of human diaphragmatic motor units during voluntary inspiratory tasks

    PubMed Central

    Butler, J E; McKenzie, D K; Gandevia, S C

    1999-01-01

    The behaviour of inspiratory motoneurones is poorly understood in humans and even for limb muscles there are few studies of motoneurone behaviour under concentric conditions. The current study assessed the discharge properties of the human phrenic motoneurones during a range of non-isometric voluntary contractions. We recorded activity from 60 motor units in the costal diaphragm of four subjects using an intramuscular electrode while subjects performed a set of voluntary inspiratory contractions. These included a range of inspiratory efforts above and below the usual tidal range: breaths of different sizes (5-40% vital capacity, VC) at a constant inspiratory flow (5% VC s−1) and breaths of a constant size (20% VC) at different inspiratory flows (2.5-20% VC s−1). For all the voluntary tasks, motor units were recruited throughout inspiration. For the various tasks, half-way through inspiration, 61-87% of the sampled motor units had been recruited. When the inspiratory task was deliberately altered, most single motor units began their discharge at a particular volume even when the rate of contraction had altered. The initial firing frequency (median, 6.5 Hz) was consistent for tasks with a constant flow regardless of the size of the breath. However, for breaths of a constant size the initial firing frequencies increased as the inspiratory flow increased (range across tasks, 4.8-9.3 Hz). The ‘final’ firing frequency at the end of inspiration increased significantly above the initial frequency for each task (by 0.8-5.2 Hz) and was higher for those tasks with higher final lung volumes and higher inspiratory flows (range across tasks, 7.8-11.0 Hz). There was no correlation within a task between the time of recruitment and the initial or final firing frequency for each motor unit. However, for each inspiratory task, initial and final firing frequencies were positively correlated. Because the discharge of three to four units could be recorded simultaneously in a

  4. Age associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SUMMARY: This 3 year longitudinal study among older adults showed that declining muscle mass, strength, power, and physical performance are independent contributing factors to increased fear of falling, while declines of muscle mass and physical performance contribute to deterioration of quality of ...

  5. Resistance training and timed amino acid supplementation protects against the loss of muscle mass and strength with disuse

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Space flight and ground-based models of weightlessness result in loss of muscle mass and strength. Amino acid supplementation and resistance training reverse these losses but their optimal combination is not known. We examined the effect of an amino acid supplement and resistance training on muscl...

  6. How Effective Is Sun Salutation in Improving Muscle Strength, General Body Endurance and Body Composition?

    PubMed Central

    Bhutkar, Milind V.; Bhutkar, Pratima M.; Taware, Govind B.; Surdi, Anil D.

    2011-01-01

    Purpose The purpose of the present study was to evaluate effects of regular practice of sun salutation on muscle strength, general body endurance and body composition. Methods Subjects (49 male and 30 female) performed 24 cycles of sun salutation, 6 days a week for 24 weeks. Upper body muscle strength was determined by 1 repetition maximum (1RM) for bench press and shoulder press technique. Back and leg dynamometry was used to assess strength of back and leg muscles. General body endurance was evaluated by push-up and sit-up tests. Body composition was assessed by noting% body fat by using bioelectric impedance analysis. Perceived intensity of exercise by subjects was noted by Borg scale. Results Muscle strength by bench press showed significant increase in male (29.49±9.70 to 36.12±9.09 Kg, P<0.001) and female (10.5±4.42 to 13.16±4.44 Kg, P<0.001) subjects. Strength by shoulder press also increased (males; 22.96±9.57 Kg to 26.53±11.05 Kg, P<0.001, females; 6.83±2.78 to 8.83±3.87, P<0.001). Endurance by push-ups & sit-ups showed similar findings in male (19.0±9.58 to 21.98±8.98, P<0.001 and 24.92±10.41 to 29.84±12.64, P<0.001 respectively) and female (14.66±6.80 to 18.56±6.97 and 13.16±7.75 to 19.23±8.25, P<0.001 respectively) subjects. A significant decrease in body fat percent was observed only in female (27.68±5.46 to 25.76±4.72, P<0.001) but not in male subjects. BMI significantly decreased in both the groups (z=4.37, P<001 and t=5.41, P<0.001 respectively). Conclusion From our observations we conclude that sun salutation can be an ideal exercise to keep oneself in optimum level of fitness. PMID:22375247

  7. Analysis of isokinetic muscle strength for sports physiotherapy research in Korean ssireum athletes.

    PubMed

    Noh, Ji-Woong; Park, Byoung-Sun; Kim, Mee-Young; Lee, Lim-Kyu; Yang, Seung-Min; Lee, Won-Deok; Shin, Yong-Sub; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Park, Jaehong; Kim, Junghwan

    2015-10-01

    [Purpose] The purpose of the present study was to elucidate the muscle conditions such as the isokinetic muscle of Korean ssireum athletes. [Subjects and Methods] This study enrolled 25 elite ssireum athletes. We measured body composition and peak torque at an angular speed at 60°/s using an isokinetic muscle strength dynamometer. [Results] The lean body mass of the left upper limb was significantly higher than that of the right upper limb. However, the lean body mass of the left lower limb was significantly lower than that of the right lower limb. The peak torque for left elbow flexion was significantly higher than that for right elbow flexion. Conversely, the peak torque for left elbow extension was significantly lower than that for right elbow extension. Furthermore, the peak torque for the left knee was significantly lower than that for the right knee for both flexion and extension. [Conclusion] The data from this study elucidate in part the muscle conditions of Korean ssireum athletes, which can be used to establish a reference for the scientific study of sports physiotherapy. PMID:26644679

  8. Analysis of isokinetic muscle strength for sports physiotherapy research in Korean ssireum athletes

    PubMed Central

    Noh, Ji-Woong; Park, Byoung-Sun; Kim, Mee-Young; Lee, Lim-Kyu; Yang, Seung-Min; Lee, Won-Deok; Shin, Yong-Sub; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Park, Jaehong; Kim, Junghwan

    2015-01-01

    [Purpose] The purpose of the present study was to elucidate the muscle conditions such as the isokinetic muscle of Korean ssireum athletes. [Subjects and Methods] This study enrolled 25 elite ssireum athletes. We measured body composition and peak torque at an angular speed at 60°/s using an isokinetic muscle strength dynamometer. [Results] The lean body mass of the left upper limb was significantly higher than that of the right upper limb. However, the lean body mass of the left lower limb was significantly lower than that of the right lower limb. The peak torque for left elbow flexion was significantly higher than that for right elbow flexion. Conversely, the peak torque for left elbow extension was significantly lower than that for right elbow extension. Furthermore, the peak torque for the left knee was significantly lower than that for the right knee for both flexion and extension. [Conclusion] The data from this study elucidate in part the muscle conditions of Korean ssireum athletes, which can be used to establish a reference for the scientific study of sports physiotherapy. PMID:26644679

  9. Growth of specific muscle strength between 6 and 18 years in contrasting socioeconomic conditions.

    PubMed

    Henneberg, M; Brush, G; Harrison, G A

    2001-05-01

    The influence of sex, age, and socioeconomic conditions on specific grip strength of 6-18-year-old individuals was studied among 1,704 males and 1,956 females belonging to the so-called "Cape Coloured" community in the western part of South Africa. Half of the participants of both sexes came from communities in the Greater Cape Town area where living conditions are comparable to those of middle-class First World communities (high SES). The other half came from the poorest rural communities of Klein Karoo (low SES). Arm circumferences, triceps skinfold thickness, and grip strength of the right and of the left hand were greater in individuals from high SES at all ages. Females within each SES group had skinfolds thicker than males, especially at older ages, and were weaker. Specific grip strength (SS), estimated as grip strength per unit area of cross section of the fat-free arm, increased with age in each group, was greater in males, and was significantly lower in low SES groups, than in the high SES ones, especially during and after puberty. It seems that SES difference in SS will persist into adulthood. Sexual differences in SS can be attributed to hormonal differences; while the SS increase with age and the difference between SES groups find no clear explanation in current theories of muscle growth and development. Since the speed of neuromuscular reaction observed in our participants is slower among low SES individuals, it seems that the difference in neuromuscular control of strength may be responsible for our findings. Differences in muscle metabolism and hormonal regulation must also be considered. PMID:11309751

  10. Unidirectional Expiratory Valve Method to Assess Maximal Inspiratory Pressure in Individuals without Artificial Airway

    PubMed Central

    Grams, Samantha Torres; Kimoto, Karen Yumi Mota; Azevedo, Elen Moda de Oliveira; Lança, Marina; de Albuquerque, André Luis Pereira; de Brito, Christina May Moran; Yamaguti, Wellington Pereira

    2015-01-01

    Introduction Maximal Inspiratory Pressure (MIP) is considered an effective method to estimate strength of inspiratory muscles, but still leads to false positive diagnosis. Although MIP assessment with unidirectional expiratory valve method has been used in patients undergoing mechanical ventilation, no previous studies investigated the application of this method in subjects without artificial airway. Objectives This study aimed to compare the MIP values assessed by standard method (MIPsta) and by unidirectional expiratory valve method (MIPuni) in subjects with spontaneous breathing without artificial airway. MIPuni reproducibility was also evaluated. Methods This was a crossover design study, and 31 subjects performed MIPsta and MIPuni in a random order. MIPsta measured MIP maintaining negative pressure for at least one second after forceful expiration. MIPuni evaluated MIP using a unidirectional expiratory valve attached to a face mask and was conducted by two evaluators (A and B) at two moments (Tests 1 and 2) to determine interobserver and intraobserver reproducibility of MIP values. Intraclass correlation coefficient (ICC[2,1]) was used to determine intraobserver and interobserver reproducibility. Results The mean values for MIPuni were 14.3% higher (-117.3 ± 24.8 cmH2O) than the mean values for MIPsta (-102.5 ± 23.9 cmH2O) (p<0.001). Interobserver reproducibility assessment showed very high correlation for Test 1 (ICC[2,1] = 0.91), and high correlation for Test 2 (ICC[2,1] = 0.88). The assessment of the intraobserver reproducibility showed high correlation for evaluator A (ICC[2,1] = 0.86) and evaluator B (ICC[2,1] = 0.77). Conclusions MIPuni presented higher values when compared with MIPsta and proved to be reproducible in subjects with spontaneous breathing without artificial airway. PMID:26360255

  11. Intramuscular sex steroid hormones are associated with skeletal muscle strength and power in women with different hormonal status

    PubMed Central

    Pöllänen, Eija; Kangas, Reeta; Horttanainen, Mia; Niskala, Paula; Kaprio, Jaakko; Butler-Browne, Gillian; Mouly, Vincent; Sipilä, Sarianna; Kovanen, Vuokko

    2015-01-01

    Estrogen (E2)-responsive peripheral tissues, such as skeletal muscle, may suffer from hormone deficiency after menopause potentially contributing to the aging of muscle. However, recently E2 was shown to be synthesized by muscle and its systemic and intramuscular hormone levels are unequal. The objective of the study was to examine the association between intramuscular steroid hormones and muscle characteristics in premenopausal women (n = 8) and in postmenopausal monozygotic twin sister pairs (n = 16 co-twins from eight pairs) discordant for the use of E2-based hormone replacement. Isometric skeletal muscle strength was assessed by measuring knee extension strength. Explosive lower body muscle power was assessed as vertical jump height. Due to sequential nature of enzymatic conversion of biologically inactive dehydroepiandrosterone (DHEA) to testosterone (T) and subsequently to E2 or dihydrotestosterone (DHT), separate linear regression models were used to estimate the association of each hormone with muscle characteristics. Intramuscular E2, T, DHT, and DHEA proved to be significant, independent predictors of strength and power explaining 59–64% of the variation in knee extension strength and 80–83% of the variation of vertical jumping height in women (P < 0.005 for all models). The models were adjusted for age, systemic E2, and total body fat mass. The statistics used took into account the lack of statistical independence of twin sisters. Furthermore, muscle cells were shown to take up and actively synthesize hormones. Present study suggests intramuscular sex steroids to associate with strength and power regulation in female muscle providing novel insight to the field of muscle aging. PMID:25645687

  12. Supplementation with a polyphenolic blend improves post-exercise strength recovery and muscle soreness

    PubMed Central

    Herrlinger, Kelli A.; Chirouzes, Diana M.; Ceddia, Michael A.

    2015-01-01

    Background Exercise can initiate a cascade of inflammatory and oxidative stress–related events leading to delayed onset muscle soreness. Polyphenols possess antioxidant and anti-inflammatory properties. Objective The current study examined the effects of a proprietary polyphenolic blend (PB), containing catechins and theaflavins, on exercise performance and recovery following an eccentric exercise challenge. Design Male participants (18–35 years of age) received placebo or PB at a low dose (PB-L, 1,000 mg/d) or high dose (PB-H, 2,000 mg/d) for 13 weeks. During the 13th week of supplementation, participants completed an eccentric exercise (40 min downhill treadmill run) followed by a strength assessment (peak torque on isokinetic leg extensions) pre-exercise, and 24, 48, and 96 h post-exercise. Muscle soreness (subjective questionnaire), markers of muscle stress (cortisol and creatine phosphokinase [CK]), and antioxidant capacity (ferric reducing ability of plasma [FRAP]) were also assessed. Results PB-H attenuated the decrease in peak torque observed in the placebo group from pre-exercise to 48 h (p=0.012) and 96 h (p=0.003) post-exercise. At 48 h post-exercise, PB-H reduced whole body and hamstring soreness (p=0.029) versus placebo. Chronic consumption of PB improved serum FRAP (p=0.039). As expected, serum cortisol and CK increased from pre- to post-exercise in all groups; however, by 96 h, cortisol and CK levels returned to pre-exercise levels following PB supplementation. At 96 h, the change in cortisol from pre- to post-exercise was significantly greater in placebo versus PB-H (p=0.039). Conclusion These findings show that chronic consumption of PB improved antioxidant status, reduced markers of muscle stress, and promoted strength recovery post-exercise. PMID:26689317

  13. Ursolic Acid-Induced Elevation of Serum Irisin Augments Muscle Strength During Resistance Training in Men

    PubMed Central

    Bang, Hyun Seok; Seo, Dae Yun; Chung, Yong Min; Oh, Kyoung-Mo; Park, Jung Jun; Arturo, Figueroa; Jeong, Seung-Hun; Kim, Nari

    2014-01-01

    Ursolic acid (UA), a type of pentacyclic triterpenoid carboxylic acid purified from natural plants, can promote skeletal muscle development. We measured the effect of resistance training (RT) with/without UA on skeletal muscle development and related factors in men. Sixteen healthy male participants (age, 29.37±5.14 years; body mass index=27.13±2.16 kg/m2) were randomly assigned to RT (n=7) or RT with UA (RT+UA, n=9) groups. Both groups completed 8 weeks of intervention consisting of 5 sets of 26 exercises, with 10~15 repetitions at 60~80% of 1 repetition maximum and a 60~90-s rest interval between sets, performed 6 times/week. UA or placebo was orally ingested as 1 capsule 3 times/day for 8 weeks. The following factors were measured pre-and post-intervention: body composition, insulin, insulin-like growth factor-1 (IGF-1), irisin, and skeletal muscle strength. Body fat percentage was significantly decreased (p<0.001) in the RT+UA group, despite body weight, body mass index, lean body mass, glucose, and insulin levels remaining unchanged. IGF-1 and irisin were significantly increased compared with baseline levels in the RT+UA group (p<0.05). Maximal right and left extension (p<0.01), right flexion (p<0.05), and left flexion (p<0.001) were significantly increased compared with baseline levels in the RT+UA group. These findings suggest that UA-induced elevation of serum irisin may be useful as an agent for the enhancement of skeletal muscle strength during RT. PMID:25352765

  14. Low ponderal index is associated with decreased muscle strength and fatigue resistance in college-aged women

    PubMed Central

    Brutsaert, Tom D.; Tamvada, Kelli H.; Kiyamu, Melisa; White, Daniel D.; Gage, Timothy B

    2011-01-01

    Poor fetal growth is associated with decrements in muscle strength likely due to changes during myogenesis. We investigated the association of poor fetal growth with muscle strength, fatigue resistance, and the response to training in the isolated quadriceps femoris. Females (20.6 yrs) born to term but below the 10th percentile of ponderal index (PI)-for-gestational-age (LOWPI, n=14) were compared to controls (HIGHPI, n=14), before and after an 8-week training. Muscle strength was assessed as grip-strength and as the maximal isometric voluntary contraction (MVC) of the quadriceps femoris. Muscle fatigue was assessed during knee extension eercise. Body composition and the maximal oxygen consumption (VO2max) were also measured. Controlling for fat free mass (FFM), LOWPI versus HIGHPI women had ~11% lower grip-strength (P=0.023), 9–24% lower MVC values (P=0.042 pre-trained; P=0.020 post-trained), a higher rate of fatigue (pre- and post-training), and a diminished training response (P=0.016). Statistical control for FFM increased rather than decreased strength differences between PI groups. The PI was not associated with VO2max or measures of body composition. Strength and fatigue decrements strongly suggest that poor fetal growth affects the pathway of muscle force generation. This could be due to neuromotor and/or muscle morphologic changes during development e.g., fiber number, fiber type, etc. Muscle from LOWPI women may also be less responsive to training. Indirectly, results also implicate muscle as a potential mediator between poor fetal growth and adult chronic disease, given muscle’s direct role in determining insulin resistance, type II diabetes, physical activity, and so forth. PMID:21641734

  15. Pelvic floor muscle strength in primiparous women according to the delivery type: cross-sectional study 1

    PubMed Central

    Mendes, Edilaine de Paula Batista; de Oliveira, Sonia Maria Junqueira Vasconcellos; Caroci, Adriana de Souza; Francisco, Adriana Amorim; Oliveira, Sheyla Guimaraes; da Silva, Renata Luana

    2016-01-01

    ABSTRACT Objectives: to compare the pelvic floor muscle strength in primiparous women after normal birth and cesarean section, related to the socio-demographic characteristics, nutritional status, dyspareunia, urinary incontinence, perineal exercise in pregnancy, perineal condition and weight of the newborn. Methods: this was a cross-sectional study conducted after 50 - 70 postpartum days, with 24 primiparous women who underwent cesarean delivery and 72 who had a normal birth. The 9301 PeritronTM was used for analysis of muscle strength. The mean muscle strength was compared between the groups by two-way analysis of variance. Results: the pelvic floor muscle strength was 24.0 cmH2O (±16.2) and 25.4 cmH2O (±14.7) in postpartum primiparous women after normal birth and cesarean section, respectively, with no significant difference. The muscular strength was greater in postpartum women with ≥ 12 years of study (42.0 ±26.3 versus 14.6 ±7.7 cmH2O; p= 0.036) and in those who performed perineal exercises (42.6±25.4 11.8±4.9 vs. cmH2O; p = 0.010), compared to caesarean. There was no difference in muscle strength according to delivery type regarding nutritional status, dyspareunia, urinary incontinence, perineal condition or newborn weight. Conclusion: pelvic floor muscle strength does not differ between primiparous women based on the type of delivery. Postpartum women with normal births, with higher education who performed perineal exercise during pregnancy showed greater muscle strength. PMID:27533267

  16. Ageing influence in the evolution of strength and muscle mass in women with fibromyalgia: the al-Ándalus project.

    PubMed

    Latorre-Román, Pedro Ángel; Segura-Jiménez, Víctor; Aparicio, Virginia A; Santos E Campos, María Aparecida; García-Pinillos, Felipe; Herrador-Colmenero, Manuel; Álvarez-Gallardo, Inmaculada C; Delgado-Fernández, Manuel

    2015-07-01

    Fibromyalgia is associated with physical disabilities in daily activities. Moreover, patients with fibromyalgia present similar levels of functional capacity and physical condition than elderly people. The aim of this study was to analyse the evolution of strength and muscle mass in women with fibromyalgia along ageing. A total sample of 492 fibromyalgia patients and 279 healthy control women were included in the study. Participants in each group were further divided into four age subgroups: subgroup 1: 30-39 years old, subgroup 2: 40-49 years old, subgroup 3: 50-59 years old and subgroup 4: 60-69 years old. Standardized field-based fitness tests were used to assess muscle strength (30-s chair stand, handgrip strength and arm curl tests). Fibromyalgia patients did not show impairment on muscle mass along ageing, without values of skeletal muscle mass index below 6.76 kg/m(2) in any group. However, in all variables of muscle strength, the fibromyalgia group showed less strength than the healthy group (p < 0.05) for all age groups. As expected, handgrip strength test showed differences along ageing only in the fibromyalgia group (p < 0.001). Age was inversely associated with skeletal muscle mass (r = -0.155, p < 0.01) and handgrip strength (r = -0.230, p < 0.001) in the FM group. Women with fibromyalgia showed a reduction in muscle strength along ageing process, with significantly lower scores than healthy women for each age group, representing a risk of dynapenia. PMID:25617055

  17. Efficiency of muscle strength training on motor function in patients with coronary artery disease: a meta-analysis

    PubMed Central

    Yang, Yu-Jie; He, Xiao-Hua; Guo, Hai-Ying; Wang, Xue-Qiang; Zhu, Yi

    2015-01-01

    Background: Existing literature has shown that patients with coronary artery disease (CAD) can benefit greatly from the strength training; therefore, the strength training should play a more important role in cardiac rehabilitation. However, the medical community may still have conservation to apply the strength training owing to no comprehensive study so far to compare the effectiveness of the strength training to the other trainings, such as aerobic training. Objective: To evaluate the effect of strength training on motor function in patients with CAD. Methods: Published articles from the earliest date available to July 2015 were identified using electronic searches. Two reviewers selected independently relevant randomized controlled trials (RCTs) investigating exercise program with strength training versus control interventions (exercise without strength training, including aerobic training and no exercise group) for the treatment of CAD patients. We examined effects of exercise with strength training versus control interventions on peak oxygen uptake (VO2peak), duration of exercise test and muscle strength. Two reviewers extracted data independently. Results: Twenty seven trials that represented 1151 participants passed the selection criteria and were evaluated for the effects of strength training in CAD patients. For improving VO2peak [SMD (95%CI) = 0.58 (0.11, 1.06)] and muscle strength [upper limb, SMD (95% CI) =0.44 (0.34, 0.55); lower limb, SMD (95% CI) =0.33 (0.16, 0.50)], exercise program with strength training were significantly more effective than one without it. But there is no significantly difference on duration of exercise test [SMD (95%CI) = 0.17 (-0.04, 0.39)] in strength training group than in control group. Conclusions: We conclude strength training is effective in improving muscle strength and VO2peak, in CAD patients, when compared to patients with control group. Furthermore, our evaluations suggest that strength training does not compromise

  18. Effects of age and sex on neuromuscular-mechanical determinants of muscle strength.

    PubMed

    Wu, Rui; Delahunt, Eamonn; Ditroilo, Massimiliano; Lowery, Madeleine; De Vito, Giuseppe

    2016-06-01

    The aim of this study was to concurrently assess the effect of age on neuromuscular and mechanical properties in 24 young (23.6 ± 3.7 years) and 20 older (66.5 ± 3.8 years) healthy males and females. Maximal strength of knee extensors (KE) and flexors (KF), contractile rate of torque development (RTD) and neural activation of agonist-antagonist muscles (surface EMG) were examined during maximal voluntary isometric contraction (MVIC). Tissue stiffness (i.e. musculo-articular stiffness (MAS) and muscle stiffness (MS)) was examined via the free-oscillation technique, whereas muscle architecture (MA) of the vastus lateralis and subcutaneous fat were measured by ultrasonography. Males exhibited a greater age-related decline for KE (47.4 %) and KF (53.1 %) MVIC, and RTD (60.4 %) when compared to females (32.9, 42.6 and 34.0 %, respectively). Neural activation of agonist muscles during KE MVIC falls markedly with ageing; however, no age and sex effects were observed in the antagonist co-activation. MAS and MS were lower in elderly compared with young participants and in females compared with males. Regarding MA, main effects for age (young 23.0 ± 3.3 vs older 19.5 ± 2.0 mm) and sex (males 22.4 ± 3.5 vs females 20.4 ± 2.7 mm) were detected in muscle thickness. For fascicle length, there was an effect of age (young 104.6 ± 8.8 vs older 89.8 ± 10.5 mm), while for pennation angle, there was an effect of sex (males 13.3 ± 2.4 vs females 11.5 ± 1.7°). These findings suggest that both neuromuscular and mechanical declines are important contributors to the age-related loss of muscle strength/function but with some peculiar sex-related differences. PMID:27189591

  19. Effect of traditional resistance and power training using rated perceived exertion for enhancement of muscle strength, power, and functional performance.

    PubMed

    Tiggemann, Carlos Leandro; Dias, Caroline Pieta; Radaelli, Regis; Massa, Jéssica Cassales; Bortoluzzi, Rafael; Schoenell, Maira Cristina Wolf; Noll, Matias; Alberton, Cristine Lima; Kruel, Luiz Fernando Martins

    2016-04-01

    The present study compared the effects of 12 weeks of traditional resistance training and power training using rated perceived exertion (RPE) to determine training intensity on improvements in strength, muscle power, and ability to perform functional task in older women. Thirty healthy elderly women (60-75 years) were randomly assigned to traditional resistance training group (TRT; n = 15) or power training group (PT; n = 15). Participants trained twice a week for 12 weeks using six exercises. The training protocol was designed to ascertain that participants exercised at an RPE of 13-18 (on a 6-20 scale). Maximal dynamic strength, muscle power, and functional performance of lower limb muscles were assessed. Maximal dynamic strength muscle strength leg press (≈58 %) and knee extension (≈20 %) increased significantly (p < 0.001) and similarly in both groups after training. Muscle power also increased with training (≈27 %; p < 0.05), with no difference between groups. Both groups also improved their functional performance after training period (≈13 %; p < 0.001), with no difference between groups. The present study showed that TRT and PT using RPE scale to control intensity were significantly and similarly effective in improving maximal strength, muscle power, and functional performance of lower limbs in elderly women. PMID:27009295

  20. The Associations between Pain Sensitivity and Knee Muscle Strength in Healthy Volunteers: A Cross-Sectional Study

    PubMed Central

    Graven-Nielsen, Thomas; Bliddal, Henning

    2013-01-01

    Objectives. To investigate associations between muscle strength and pain sensitivity among healthy volunteers and associations between different pain sensitivity measures. Methods. Twenty-eight healthy volunteers (21 females) participated. Pressure pain thresholds (PPTs) were obtained from 1) computer-controlled pressure algometry on the vastus lateralis and deltoid muscles and on the infrapatellar fat pad and 2) computerized cuff pressure algometry applied on the lower leg. Deep-tissue pain sensitivity (intensity and duration) was assessed by hypertonic saline injections into the vastus lateralis, deltoid, and infrapatellar fat pad. Quadriceps and hamstring muscle strength was assessed isometrically at 60-degree knee flexion using a dynamometer. Associations between pain sensitivity and muscle strength were investigated using multiple regressions including age, gender, and body mass index as covariates. Results. Knee extension strength was associated with computer-controlled PPT on the vastus lateralis muscle. Computer-controlled PPTs were significantly correlated between sites (r > 0.72) and with cuff PPT (r > 0.4). Saline induced pain intensity and duration were correlated between sites (r > 0.39) and with all PPTs (r < −0.41). Conclusions. Pressure pain thresholds at the vastus lateralis are positively associated with knee extensor muscle strength. Different pain sensitivity assessment methods are generally correlated. The cuff PPT and evoked infrapatellar pain seem to reflect the general pain sensitivity. This trial is registered with ClinicalTrials.gov: NCT01351558. PMID:24167727

  1. Comparison of pulmonary function and back muscle strength according to the degree of spinal curvature of healthy adults

    PubMed Central

    You, Jae Eung; Lee, Hye Young; Kim, Kyoung

    2015-01-01

    [Purpose] Degree of curvature on the spine is known to affect respiratory function and back muscle activation. We compared pulmonary function and back muscle strength according to the degree of curvature of the spine of healthy adults. [Subjects and Methods] Twenty-three healthy volunteers were enrolled. They were divided into two groups according to the degree of curvature of the spine: the below 2° group, and the above 2° group. The degree of curvature was assessed using the Adams forward bending test and a scoliometer. A pulmonary function test (PFT) was conducted, and back muscle strength was measured. [Results] No significant differences in PFT were found between the below 2° group and the above 2° group, in terms of forced vital capacity (FVC), forced expiratory volume in one second (FEV1), ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC), or peak expiratory flow (PEF). However, back muscle strength in the below 2 group was significantly higher than that of the above 2 group. [Conclusion] Our findings indicate that the degree of curvature of the spine is associated with back muscle strength in subjects who have spinal curvature within the normal range. Therefore, evaluation and treatment of back muscle strength might be helpful for preventing the progress of curvature of the spine in adolescents with potential scoliosis. PMID:26180321

  2. Comparison of pulmonary function and back muscle strength according to the degree of spinal curvature of healthy adults.

    PubMed

    You, Jae Eung; Lee, Hye Young; Kim, Kyoung

    2015-06-01

    [Purpose] Degree of curvature on the spine is known to affect respiratory function and back muscle activation. We compared pulmonary function and back muscle strength according to the degree of curvature of the spine of healthy adults. [Subjects and Methods] Twenty-three healthy volunteers were enrolled. They were divided into two groups according to the degree of curvature of the spine: the below 2° group, and the above 2° group. The degree of curvature was assessed using the Adams forward bending test and a scoliometer. A pulmonary function test (PFT) was conducted, and back muscle strength was measured. [Results] No significant differences in PFT were found between the below 2° group and the above 2° group, in terms of forced vital capacity (FVC), forced expiratory volume in one second (FEV1), ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC), or peak expiratory flow (PEF). However, back muscle strength in the below 2 group was significantly higher than that of the above 2 group. [Conclusion] Our findings indicate that the degree of curvature of the spine is associated with back muscle strength in subjects who have spinal curvature within the normal range. Therefore, evaluation and treatment of back muscle strength might be helpful for preventing the progress of curvature of the spine in adolescents with potential scoliosis. PMID:26180321

  3. Variants of the IL-10 gene associate with muscle strength in elderly from rural Africa: a candidate gene study

    PubMed Central

    Beenakker, Karel G M; Koopman, Jacob J E; van Bodegom, David; Kuningas, Maris; Slagboom, Pieternella E; Meij, Johannes J; Maier, Andrea B; Westendorp, Rudi G J

    2014-01-01

    Recently, it has been shown that the capacity of the innate immune system to produce cytokines relates to skeletal muscle mass and strength in older persons. The interleukin-10 (IL-10) gene regulates the production capacities of IL-10 and tumour necrosis factor-α (TNF-α). In rural Ghana, IL-10 gene variants associated with different production capacities of IL-10 and TNF-α are enriched compared with Caucasian populations. In this setting, we explored the association between these gene variants and muscle strength. Among 554 Ghanaians aged 50 years and older, we determined 20 single nucleotide polymorphisms in the IL-10 gene, production capacities of IL-10 and TNF-α in whole blood upon stimulation with lipopolysaccharide (LPS) and handgrip strength as a proxy for skeletal muscle strength. We distinguished pro-inflammatory haplotypes associated with low IL-10 production capacity and anti-inflammatory haplotypes with high IL-10 production capacity. We found that distinct haplotypes of the IL-10 gene associated with handgrip strength. A pro-inflammatory haplotype with a population frequency of 43.2% was associated with higher handgrip strength (P = 0.015). An anti-inflammatory haplotype with a population frequency of 7.9% was associated with lower handgrip strength (P = 0.006). In conclusion, variants of the IL-10 gene contributing to a pro-inflammatory cytokine response associate with higher muscle strength, whereas those with anti-inflammatory response associate with lower muscle strength. Future research needs to elucidate whether these effects of variation in the IL-10 gene are exerted directly through its role in the repair of muscle tissue or indirectly through its role in the defence against infectious diseases. PMID:25040424

  4. Longitudinal decline of lower extremity muscle power in healthy and mobility-limited older adults: influence of muscle mass, strength, composition, neuromuscular activation and single fiber contractile properties

    PubMed Central

    Reid, Kieran F.; Pasha, Evan; Doros, Gheorghe; Clark, David J.; Patten, Carolynn; Phillips, Edward M.; Frontera, Walter R.; Fielding, Roger A.

    2013-01-01

    Purpose This longitudinal study examined the major physiological mechanisms that determine the age-related loss of lower extremity muscle power in two distinct groups of older humans. We hypothesized that after ~ 3 years of follow-up, mobility-limited older adults (mean age: 77.2 ± 4, n = 22, 12 females) would have significantly greater reductions in leg extensor muscle power compared to healthy older adults (74.1 ± 4, n = 26, 12 females). Methods Mid-thigh muscle size and composition were assessed using computed tomography. Neuromuscular activation was quantified using surface electromyography and vastus lateralis single muscle fibers were studied to evaluate intrinsic muscle contractile properties. Results At follow-up, the overall magnitude of muscle power loss was similar between groups: mobility-limited: −8.5% vs. healthy older: −8.8%, P > 0.8. Mobility-limited elders had significant reductions in muscle size (−3.8%, P< 0.01) and strength (−5.9%, P< 0.02), however, these parameters were preserved in healthy older (P ≥ 0.7). Neuromuscular activation declined significantly within healthy older but not in mobility-limited participants. Within both groups, the cross sectional areas of type I and type IIA muscle fibers were preserved while substantial increases in single fiber peak force ( > 30%), peak power (> 200%) and unloaded shortening velocity (>50%) were elicited at follow-up. Conclusion Different physiological mechanisms contribute to the loss of lower extremity muscle power in healthy older and mobility-limited older adults. Neuromuscular changes may be the critical early determinant of muscle power deficits with aging. In response to major whole muscle decrements, major compensatory mechanisms occur within the contractile properties of surviving single muscle fibers in an attempt to restore overall muscle power and function with advancing age. PMID:24122149

  5. Knee muscle strength at varying angular velocities and associations with gross motor function in ambulatory children with cerebral palsy.

    PubMed

    Hong, Wei-Hsien; Chen, Hseih-Ching; Shen, I-Hsuan; Chen, Chung-Yao; Chen, Chia-Ling; Chung, Chia-Ying

    2012-01-01

    The aim of this study was to evaluate the relationships of muscle strength at different angular velocities and gross motor functions in ambulatory children with cerebral palsy (CP). This study included 33 ambulatory children with spastic CP aged 6-15 years and 15 children with normal development. Children with CP were categorized into level I (n=17) or level II (n=16) according to Gross Motor Function Classification System (GMFCS) levels. All children underwent curl-up test and isokinetic tests of the knee extensor and flexor muscle. Children with CP underwent the gross motor function assessments, including the Gross Motor Function Measure (GMFM-66) and the gross motor subtests of Bruininks-Oseretsky Test of Motor Proficiency (BOTMP). The hamstring-quadriceps ratio (HQ ratio) was calculated as 100%×(isokinetic peak torque of hamstring (knee flexor)/isokinetic peak torque of quadriceps (knee extensor)). Children with GMFCS level II had lower BOTMP and GMFM-66 scores, curl-up scores, HQ ratio, and knee muscle strength, especially knee flexor, compared to those with GMFCS level I. The regression analysis showed that knee flexor torques at 60 and 90°/s are mainly related to balance (r(2)=0.167, p=0.011) and strength (r(2)=0.243, p=0.002) while knee flexor torques at 120°/s mainly contribute to running speed and agility (r(2)=0.372, p<0.001). These findings suggest that children with CP had knee strength deficits, especially knee flexor. Postural muscle (knee flexor) strength dominated gross motor function than antigravity muscle strength (knee extensor). The knee flexor strength at different angular velocities was associated with various gross motor tasks. The HQ ratio may be used as a potential biomarker to probe the therapeutic effectiveness for muscle strengthening in these children. These data may allow clinician for formulating effective muscle strengthening strategies for these children. PMID:22853889

  6. Changes in Muscle Mass, Muscle Strength and Power, but not Physical Function are Related to Testosterone Dose in Healthy Older Men

    PubMed Central

    Storer, Thomas W.; Woodhouse, Linda; Magliano, Lynne; Singh, Atam B.; Dzekov, Connie; Dzekov, Jeanne; Bhasin, Shalender

    2008-01-01

    OBJECTIVES: To examine the effect of graded doses of testosterone on physical function (PF) and muscle performance in healthy, older men. DESIGN: Randomized, double-blind, placebo controlled clinical trial. SETTING: General Clinical Research Center PARTICIPANTS: Community-dwelling healthy older men aged 60-75 yr, N=44. INTERVENTION: Monthly treatment with a gonadotropin releasing hormone agonist plus 25, 50, 125, or 300 mg/wk testosterone enanthate IM for 20 weeks. MEASUREMENTS: Skeletal muscle mass (SMM) was estimated by DEXA. Leg press strength was measured by 1-RM, leg power by Nottingham Leg Rig, and muscle fatigability by repetitions to failure in the leg press exercise. Stair climbing, 6-m and 400-m walking speed, and a timed-up-and-go (TUG) were used to assess PF. RESULTS: Significant T dose- and concentration-dependent increases were observed in SMM (P<0.001) and maximal strength (P=0.001), but not muscle fatigability. Leg power also increased dose-dependently (P=0.048). In contrast, changes in self-selected normal and fast walking speed over 6-m or 400-m, stair climbing power, and time for the TUG were not significantly related to T-dose, T-concentrations, or changes in muscle strength or power, or SMM. CONCLUSION: Testosterone administration was associated with dose-dependent increases in SMM, leg strength and power, but did not improve muscle fatigability or physical function. The observation that physical function scores did not improve linearly with strength suggests that our high functioning older men were already in the asymptotic region of the curve describing the physical function – strength relationship. PMID:18795988

  7. Comparison of knee laxity and isokinetic muscle strength in patients with a posterior cruciate ligament injury

    PubMed Central

    Jeon, Kyoungkyu

    2016-01-01

    [Purpose] The aim of this study was to compare knee laxity and isokinetic muscle strength in patients with an isolated posterior cruciate ligament injury. [Subjects and Methods] Twenty high school rugby players with a previous posterior cruciate ligament injury and abnormal findings higher than surgical grade I were included. Laxity with 132 N of pressure was measured using Kneelax 3 to assess the stability of the posterior cruciate ligament, and flexor and extensor torques were measured at 60°/sec, 180°/sec, and 240°/sec to measure the isokinetic muscle strength of the knee joint. The average and standard deviation values were extracted from all data to assess the measured data. [Results] Regarding the ipsilateral and contralateral laxity, the deviation value at the peak force and maximum manual drawer was statistically significant. The peak torque and peak torque per body weight in isokinetic measurements were significantly different only for knee extensor torque at 60°/sec, 180°/sec, and 240°/sec. [Conclusion] Return to normal activities post injury is important. Thus base data gathered by comparing patients’ ipsilateral and contralateral sides will serve as essential criteria for structuring future rehabilitation programs to facilitate functional improvements. PMID:27134367

  8. Tensile strength and dilatational elasticity of giant sarcolemmal vesicles shed from rabbit muscle.

    PubMed Central

    Nichol, J A; Hutter, O F

    1996-01-01

    1. Mechanical properties of the surface membrane of skeletal muscle were determined on sarcolemmal vesicles (mean diameter, 71 microns) shed by rabbit psoas muscle swelling in 140 mM KC1 containing collagenase. 2. Vesicles were stressed by partial aspiration into parallel bore pipettes. The isotropic membrane tension so created caused an increase in membrane area which expresses itself in an elongation of the vesicle projection into the pipette. 3. For individual vesicles, a linear relationship between membrane tension and membrane area increase was found up to the point when the vesicle burst, i.e. sarcolemmal vesicles behaved as perfectly elastic structures. 4. The maximum tension sarcolemmal vesicles could sustain before bursting was 12.4 +/- 0.2 mN m-1 (median +/- 95% confidence interval), and the corresponding fractional increase in membrane area was 0.026 +/- 0.005 (median +/- 95% confidence interval). The elastic modulus of area expansion was 490 +/- 88 mN m-1 (mean +/- S.D.). 5. In conformity with cited comparable work on red blood cells and artificial lipid vesicles, the strength and area elasticity of the skeletal muscle membrane are considered properties of the fluid lipid matrix of the membrane and of the degree to which the bilayer is perturbed by lipid-protein interaction. Images Figure 2 PMID:8735704

  9. Angular Velocity Affects Trunk Muscle Strength and EMG Activation during Isokinetic Axial Rotation

    PubMed Central

    Fan, Jian-Zhong; Liu, Xia; Ni, Guo-Xin

    2014-01-01

    Objective. To evaluate trunk muscle strength and EMG activation during isokinetic axial rotation at different angular velocities. Method. Twenty-four healthy young men performed isokinetic axial rotation in right and left directions at 30, 60, and 120 degrees per second angular velocity. Simultaneously, surface EMG was recorded on external oblique (EO), internal oblique (IO), and latissimus dorsi (LD) bilaterally. Results. In each direction, with the increase of angular velocity, peak torque decreased, whereas peak power increased. During isokinetic axial rotation, contralateral EO as well as ipsilateral IO and LD acted as primary agonists, whereas, ipsilateral EO as well as contralateral IO and LD acted as primary antagonistic muscles. For each primary agonist, the root mean square values decreased with the increase of angular velocity. Antagonist coactiviation was observed at each velocity; however, it appears to be higher with the increase of angular velocity. Conclusion. Our results suggest that velocity of rotation has great impact on the axial rotation torque and EMG activity. An inverse relationship of angular velocity was suggested with the axial rotation torque as well as root mean square value of individual trunk muscle. In addition, higher velocity is associated with higher coactivation of antagonist, leading to a decrease in torque with the increase of velocity. PMID:24804227

  10. Motor imagery muscle contraction strength influences spinal motor neuron excitability and cardiac sympathetic nerve activity

    PubMed Central

    Bunno, Yoshibumi; Suzuki, Toshiaki; Iwatsuki, Hiroyasu

    2015-01-01

    [Purpose] The aim of this study was to investigate the changes in spinal motor neuron excitability and autonomic nervous system activity during motor imagery of isometric thenar muscle activity at 10% and 50% maximal voluntary contraction (MVC). [Methods] The F-waves and low frequency/high frequency (LF/HF) ratio were recorded at rest, during motor imagery, and post-trial. For motor imagery trials, subjects were instructed to imagine thenar muscle activity at 10% and 50% MVC while holding the sensor of a pinch meter for 5 min. [Results] The F-waves and LF/HF ratio during motor imagery at 50% MVC were significantly increased compared with those at rest, whereas those during motor imagery at 10% MVC were not significantly different from those at rest. The relative values of the F/M amplitude ratio during motor imagery at 50% MVC were significantly higher than those at 10% MVC. The relative values of persistence and the LF/HF ratio during motor imagery were similar during motor imagery at the two muscle contraction strengths. [Conclusion] Motor imagery can increase the spinal motor neuron excitability and cardiac sympathetic nerve activity. Motor imagery at 50% MVC may be more effective than motor imagery at 10% MVC. PMID:26834354

  11. Strength training improves muscle aerobic capacity and glucose tolerance in elderly.

    PubMed

    Frank, P; Andersson, E; Pontén, M; Ekblom, B; Ekblom, M; Sahlin, K

    2016-07-01

    The primary aim of this study was to investigate the effect of short-term resistance training (RET) on mitochondrial protein content and glucose tolerance in elderly. Elderly women and men (age 71 ± 1, mean ± SEM) were assigned to a group performing 8 weeks of resistance training (RET, n = 12) or no training (CON, n = 9). The RET group increased in (i) knee extensor strength (concentric +11 ± 3%, eccentric +8 ± 3% and static +12 ± 3%), (ii) initial (0-30 ms) rate of force development (+52 ± 26%) and (iii) contents of proteins related to signaling of muscle protein synthesis (Akt +69 ± 20 and mammalian target of rapamycin +69 ± 32%). Muscle fiber type composition changed to a more oxidative profile in RET with increased amount of type IIa fibers (+26.9 ± 6.8%) and a trend for decreased amount of type IIx fibers (-16.4 ± 18.2%, P = 0.068). Mitochondrial proteins (OXPHOS complex II, IV, and citrate synthase) increased in RET by +30 ± 11%, +99 ± 31% and +29 ± 8%, respectively. RET resulted in improved oral glucose tolerance measured as reduced area under curve for glucose (-21 ± 26%) and reduced plasma glucose 2 h post-glucose intake (-14 ± 5%). In CON parameters were unchanged or impaired. In conclusion, short-term resistance training in elderly not only improves muscular strength, but results in robust increases in several parameters related to muscle aerobic capacity. PMID:26271931

  12. Sarcopenia, Dynapenia, and the Impact of Advancing Age on Human Skeletal Muscle Size and Strength; a Quantitative Review

    PubMed Central

    Mitchell, W. Kyle; Williams, John; Atherton, Philip; Larvin, Mike; Lund, John; Narici, Marco

    2012-01-01

    Changing demographics make it ever more important to understand the modifiable risk factors for disability and loss of independence with advancing age. For more than two decades there has been increasing interest in the role of sarcopenia, the age-related loss of muscle or lean mass, in curtailing active and healthy aging. There is now evidence to suggest that lack of strength, or dynapenia, is a more constant factor in compromised wellbeing in old age and it is apparent that the decline in muscle mass and the decline in strength can take quite different trajectories. This demands recognition of the concept of muscle quality; that is the force generating per capacity per unit cross-sectional area (CSA). An understanding of the impact of aging on skeletal muscle will require attention to both the changes in muscle size and the changes in muscle quality. The aim of this review is to present current knowledge of the decline in human muscle mass and strength with advancing age and the associated risk to health and survival and to review the underlying changes in muscle characteristics and the etiology of sarcopenia. Cross-sectional studies comparing young (18–45 years) and old (>65 years) samples show dramatic variation based on the technique used and population studied. The median of values of rate of loss reported across studies is 0.47% per year in men and 0.37% per year in women. Longitudinal studies show that in people aged 75 years, muscle mass is lost at a rate of 0.64–0.70% per year in women and 0.80–00.98% per year in men. Strength is lost more rapidly. Longitudinal studies show that at age 75 years, strength is lost at a rate of 3–4% per year in men and 2.5–3% per year in women. Studies that assessed changes in mass and strength in the same sample report a loss of strength 2–5 times faster than loss of mass. Loss of strength is a more consistent risk for disability and death than is loss of muscle mass. PMID:22934016

  13. Effects of 8 weeks' specific physical training on the rotator cuff muscle strength and technique of javelin throwers.

    PubMed

    Kim, Hyeyoung; Lee, Youngsun; Shin, Insik; Kim, Kitae; Moon, Jeheon

    2014-10-01

    [Purpose] For maximum efficiency and to prevent injury during javelin throwing, it is critical to maintain muscle balance and coordination of the rotator cuff and the glenohumeral joint. In this study, we investigated the change in the rotator cuff muscle strength, throw distance and technique of javelin throwers after they had performed a specific physical training that combined elements of weight training, function movement screen training, and core training. [Subjects] Ten javelin throwers participated in this study: six university athletes in the experimental group and four national-level athletes in the control group. [Methods] The experimental group performed 8 weeks of the specific physical training. To evaluate the effects of the training, measurements were performed before and after the training for the experimental group. Measurements comprised anthropometry, isokinetic muscle strength measurements, the function movement screen test, and movement analysis. [Results] After the specific physical training, the function movement screen score and external and internal rotator muscle strength showed statistically significant increases. Among kinematic factors, only pull distance showed improvement after training. [Conclusion] Eight weeks of specific physical training for dynamic stabilizer muscles enhanced the rotator cuff muscle strength, core stability, throw distance, and flexibility of javelin throwers. These results suggest that specific physical training can be useful for preventing shoulder injuries and improving the performance for javelin throwers. PMID:25364111

  14. Relationship between Isometric Strength of Six Lower Limb Muscle Groups and Motor Skills among Nursing Home Residents.

    PubMed

    Buckinx, F; Croisier, J L; Reginster, J Y; Petermans, J; Goffart, E; Bruyère, O

    2015-01-01

    This research aimed to assess the correlation between isometric muscle strength of the lower limb and motor skills. This is a cross sectional study performed among volunteer nursing home residents included in the SENIOR (Sample of Elderly Nursing home Individuals: an Observational Research) cohort. The present analysis focused on isometric muscle strength of 6 lower limb muscle groups (i.e. knee extensors, knee flexors, hip abductors, hip extensors, ankle flexors and ankle extensors), assessed using a validated hand-held dynamometer (i.e. the MicroFET2 device), and motor skills evaluated using the Tinetti test, the Timed Up and Go test, the Short Physical Performance Battery test (SPPB) and the walking speed. The relationship between all these parameters was tested by means of a multiple correlation, adjusted on age, sex and body mass index. 450 nursing home residents (69.8% of women) with a mean age of 83.1±9.4 years were included in this study. Our results showed a significant inverse correlation between lower limb muscle strength and the time required to perform the TUG test or gait speed, except for ankle flexors and ankle extensors. The relationship between the Tinetti test or the SPPB score, and lower limb muscle strength was significant, except for ankle flexors and ankle extensors. In conclusion, a positive association between lower limb muscle strength of the four main muscle groups and motor skills of the elderly nursing residents was found in this research. Therefore, special attention should be given to these muscle groups during rehabilitation programs. PMID:27031016

  15. Strength Training Induces Muscle Hypertrophy and Functional Gains in Black Prostate Cancer Patients Despite Androgen Deprivation Therapy

    PubMed Central

    Hurley, Ben F.

    2013-01-01

    Background. Androgen deprivation therapy (ADT) for prostate cancer (PCa) is associated with weakness, fatigue, sarcopenia, and reduced quality of life (QoL). Black men have a higher incidence and mortality from PCa than Caucasians. We hypothesized that despite ADT, strength training (ST) would increase muscle power and size, thereby improving body composition, physical function, fatigue levels, and QoL in older black men with PCa. Methods. Muscle mass, power, strength, endurance, physical function, fatigue perception, and QoL were measured in 17 black men with PCa on ADT before and after 12 weeks of ST. Within-group differences were determined using t tests and regression models. Results. ST significantly increased total body muscle mass (2.7%), thigh muscle volume (6.4%), power (17%), and strength (28%). There were significant increases in functional performance (20%), muscle endurance (110%), and QoL scores (7%) and decreases in fatigue perception (38%). Improved muscle function was associated with higher functional performance (R 2 = 0.54) and lower fatigue perception (R 2 = 0.37), and both were associated with improved QoL (R 2 = 0.45), whereas fatigue perception tended to be associated with muscle endurance (R 2 = 0.37). Conclusions. ST elicits muscle hypertrophy even in the absence of testosterone and is effective in counteracting the adverse functional consequences of ADT in older black men with PCa. These improvements are associated with reduced fatigue perception, enhanced physical performance, and improved QoL. Thus, ST may be a safe and well-tolerated therapy to prevent the loss of muscle mass, strength, and power commonly observed during ADT. PMID:23089339

  16. [The relevance of muscle strength--extensors of the knee on pain relief in elderly people with knee osteoarthritis].

    PubMed

    Slivar, Senka Rendulić; Peri, Dusan; Jukić, Igor

    2011-01-01

    The main aim of this study was to evaluate muscle strength after short-term exercise program by elderly people with knee osteoarthritis that usually non exercising and to estimate if this change have influence on decrease of the pain. This study was longitudinal experiment that involved thirty participants aged 61-80 years with clinical signs and radiographic evidence of knee OA stage Kellgren II and III. They completed individual strengthening program knee muscle stabilisator and hydrotherapy in the pool during two weeks. Muscle strength and pain was estimated pre and post experimental time. The results are analysed by SPSS programme, version 15.0 for Windows. Values demonstrated decreasing degrees of the pain and increasing of muscle strength. The pain decreased 33% in advance, final pain oposite initial estimated 2.4 degrees smaller by VAS. Muscle strength for stronger leg was (initial/final) 93.10/106.33 kg/cm2 (t-test 3.584*, p < 0.001), and for weak leg 71.93/83.37 kg/cm2 (t-test 3.118* p < 0.004). Regression analysis gave small valuables of determination coefficient (R2 of 0.014-0.081) and regression coefficient (B of 0.004-0.015) for stronger and weaker leg. Exercises produced significant increase in muscle strength and decrease in pain in OA of the knee. Hypothesis that increase of muscle quadriceps strength have influence on decrease of the pain in the knee is not confirmed. PMID:21751572

  17. Changes in Muscle Strength in U19 Soccer Players During an Annual Training Cycle

    PubMed Central

    Lehnert, Michal; Xaverová, Zuzana; De Ste Croix, Mark

    2014-01-01

    The aim of the study was to investigate the seasonal variation in isokinetic strength of the knee flexors and extensors, and conventional (H/QCONV) and functional (H/QFUNC) hamstring to quadriceps strength ratios in highly trained adolescent soccer players. The players (n=11; age 17.8±0.3) were measured at the end of the competitive season (autumn), at the beginning and the end of pre-season (winter) and during the sixth week of a new competitive season. Isokinetic peak torque (concentric and eccentric) was measured at 60°·s-1 in a sitting position with the hip flexed at 100°. The testing range of motion was set from 10 – 90° of knee flexion. The players performed a set of five maximum repetitions for both the dominant and non-dominant leg. Statistically significant differences (p<0.001) between the four seasonal measurements were noted for peak torque of the dominant leg knee flexors in concentric muscle action only. A post hoc analysis revealed a statistically significant increase in peak torque from the 1st to the 4th measurement (p<0.001; d=0.692) and from the 2nd to the 4th (p<0.01; d=0.564). The differences in the changes of peak torque of the knee flexors and extensors depending on type of muscle action and tendencies found in the H/Q ratios throughout the annual training cycle indicate that strength assessment of the knee flexors and extensors and their balance throughout the annual training cycle could be beneficial for elite male adolescent soccer players both in terms of performance and risk of injury. PMID:25414751

  18. Reducing resistance training volume during Ramadan improves muscle strength and power in football players.

    PubMed

    Rebaï, H; Chtourou, H; Zarrouk, N; Harzallah, A; Kanoun, I; Dogui, M; Souissi, N; Tabka, Z

    2014-05-01

    We aimed to examine the effect of maintaining or reducing resistance training volume during Ramadan-intermittent-fasting (RIF) on short-term maximal performances. 20 footballers (age: 18.4 ± 0.8 years; body-mass: 72.4 ± 4.1 kg; height: 183.4 ± 4.6 cm) were matched and randomly assigned to a normal-training-group (G1) or a tapering-group (G2). They were tested for muscular strength (maximal-voluntary-contraction) and power (squat-jump and counter-movement-jump) 1 month before RIF (T0), 1 week before RIF (T1), after 2 weeks of fasting (T2) and at the end of RIF (T3). From T1 to T2, subjects performed a whole-body resistance training program (8-repetitions × 4-sets with 4-min recovery in-between). During RIF, G1 maintained the same training program, while G2 performed a period of reduced training volume (3 sets/exercise; - 22%). Muscle strength and power increased significantly from T0 to T1, from T0 to T2 and from T0 to T3 in G1 and G2 and from T1 to T2 and from T1 to T3 only in G2 (p<0.05). Performance was higher in G2 than G1 during T2 (p<0.01). Moreover, the ∆-change of performance between T0 and T2 and T3 was significantly higher in G2 than G1 (p<0.05). For young soccer players, a tapering period characterized by a reduced training volume during RIF may lead to significant improvement in muscle strength and power. PMID:24048913

  19. Higher Daily Physical Activities Continue to Preserve Muscle Strength After Mid-Life, But Not Muscle Mass After Age of 75.

    PubMed

    Hwang, An-Chun; Zhan, Yu-Rui; Lee, Wei-Ju; Peng, Li-Ning; Chen, Liang-Yu; Lin, Ming-Hsien; Liu, Li-Kuo; Chen, Liang-Kung

    2016-05-01

    The objective of this study is to explore the impact of aging and daily physical activities (PA) on muscle mass and muscle strength among community-dwelling people in Taiwan.The design is a cross-sectional study. Setting is a population-based community study.One thousand eight hundred thirty-nine community-dwelling people aged 50 years and older in Taiwan participated in the study.Measurements include demographic characteristics, Charlson Comorbidity Index (CCI) for multimorbidity, mini-nutritional assessment (MNA) for nutritional evaluation, functional autonomy measurement system (SMAF) for functional capacity, Chinese version mini mental state examination (MMSE), 5-item Taiwan Geriatric Depression Scale (TGDS-5), Chinese version of International Physical Activity Questionnaire (IPAQ), height-adjusted skeletal muscle index (SMI) by dual-energy X-ray absorptiometry, handgrip strength, timed 6-m walking test for usual gait speed. Laboratory measurements include testosterone, sex-hormone binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEA-S), insulin-like growth factor-1 (IGF-1), high-sensitivity C-reactive protein (hsCRP), 25-OH vitamin D, and insulin resistance.After adjusted for age, the lowest PA tertile was associated with multimorbidity, poorer functional capacity and nutritional status, more depressive symptoms, lower SMI and lower handgrip strength, and lower free androgen index (FAI) in men. The negative association between PA and low SMI was more significant among subjects aged younger than 65 and the association decreased with older age. For subjects aged younger than 65, moderate daily PA (Q2) group had lower risk of low SMI compared with Q1 participants (OR: 0.62, 95% CI = 0.39-0.98, P = 0.040). For muscle strength, higher daily PA was associated with lower risk of low handgrip strength after age of 65 and the effect was dose-dependent. The effect was attenuated by potential confounders during age 65 to 74, while after age 75, the

  20. Higher Daily Physical Activities Continue to Preserve Muscle Strength After Mid-Life, But Not Muscle Mass After Age of 75

    PubMed Central

    Hwang, An-chun; Zhan, Yu-Rui; Lee, Wei-Ju; Peng, Li-Ning; Chen, Liang-Yu; Lin, Ming-Hsien; Liu, Li-Kuo; Chen, Liang-Kung

    2016-01-01

    Abstract The objective of this study is to explore the impact of aging and daily physical activities (PA) on muscle mass and muscle strength among community-dwelling people in Taiwan. The design is a cross-sectional study. Setting is a population-based community study. One thousand eight hundred thirty-nine community-dwelling people aged 50 years and older in Taiwan participated in the study. Measurements include demographic characteristics, Charlson Comorbidity Index (CCI) for multimorbidity, mini-nutritional assessment (MNA) for nutritional evaluation, functional autonomy measurement system (SMAF) for functional capacity, Chinese version mini mental state examination (MMSE), 5-item Taiwan Geriatric Depression Scale (TGDS-5), Chinese version of International Physical Activity Questionnaire (IPAQ), height-adjusted skeletal muscle index (SMI) by dual-energy X-ray absorptiometry, handgrip strength, timed 6-m walking test for usual gait speed. Laboratory measurements include testosterone, sex-hormone binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEA-S), insulin-like growth factor-1 (IGF-1), high-sensitivity C-reactive protein (hsCRP), 25-OH vitamin D, and insulin resistance. After adjusted for age, the lowest PA tertile was associated with multimorbidity, poorer functional capacity and nutritional status, more depressive symptoms, lower SMI and lower handgrip strength, and lower free androgen index (FAI) in men. The negative association between PA and low SMI was more significant among subjects aged younger than 65 and the association decreased with older age. For subjects aged younger than 65, moderate daily PA (Q2) group had lower risk of low SMI compared with Q1 participants (OR: 0.62, 95% CI = 0.39–0.98, P = 0.040). For muscle strength, higher daily PA was associated with lower risk of low handgrip strength after age of 65 and the effect was dose-dependent. The effect was attenuated by potential confounders during age 65 to 74, while after

  1. Decreased functional capacity and muscle strength in elderly women with metabolic syndrome

    PubMed Central

    Vieira, Denis Cesar Leite; Tibana, Ramires Alsamir; Tajra, Vitor; Nascimento, Dahan da Cunha; de Farias, Darlan Lopes; de Oliveira Silva, Alessandro; Teixeira, Tatiane Gomes; Fonseca, Romulo Maia Carlos; de Oliveira, Ricardo Jacó; Mendes, Felipe Augusto dos Santos; Martins, Wagner Rodrigues; Funghetto, Silvana Schwerz; de Oliveira Karnikowski, Margo Gomes; Navalta, James Wilfred; Prestes, Jonato

    2013-01-01

    Purpose To compare the metabolic parameters, flexibility, muscle strength, functional capacity, and lower limb muscle power of elderly women with and without the metabolic syndrome (MetS). Methods This cross-sectional study included 28 older women divided into two groups: with the MetS (n = 14; 67.3 ± 5.5 years; 67.5 ± 16.7 kg; 1.45 ± 0.35 m; 28.0 ± 7.6 kg/m2), and without the MetS (n = 14; 68.7 ± 5.3 years; 58.2 ± 9.9 kg; 1.55 ± 0.10 m; 24.3 ± 3.8 kg/m2). Body composition was evaluated by dual-energy X-ray absorptiometry and dynamic muscle strength was assessed by one-maximum repetition (1RM) tests in leg press, bench press and biceps curl exercises. Six-minute walk test, Timed Up and Go (TUG); 30-second sitting-rising; arm curl using a 2-kg dumbbell, sit-and-reach (flexibility), and vertical jump tests were performed. Results There was no difference between groups regarding age (P = 0.49), height (P = 0.46), body fat (%) (P = 0.19), systolic (P = 0.64), diastolic (P = 0.41) and mean blood pressure (P = 0.86), 30-second sitting-rising (P = 0.57), 30-s arm curl (P = 0.73), leg press 1RM (P = 0.51), bench press 1RM (P = 0.77), and biceps curl 1RM (P = 0.85). However, women without the MetS presented lower body mass (P = 0.001), body mass index (BMI) (P = 0.0001), waist circumference (P = 0.02), waist-to-height ratio (P = 0.02), fat body mass (kg) (P = 0.05), lean body mass (kg) (P = 0.02), blood glucose (P = 0.05), triglycerides (P = 0.03), Z-score for the MetS (P = 0.05), higher high-density lipoprotein-cholesterol (HDL-C) (P = 0.002), better performance on TUG (P = 0.01), flexibility (P = 0.03), six-minute walk test (P = 0.04), vertical jump (P = 0.05) and relative muscle strength for leg press (P = 0.03), bench press (P = 0.04) and biceps curl (P = 0.002) exercises as compared to women with the MetS. Conclusion Elderly women with the MetS have higher metabolic risk profile and lower functional capacity, muscle strength, lower limb power and flexibility as

  2. Klotho, a new marker for osteoporosis and muscle strength in β-thalassemia major.

    PubMed

    Baldan, Alessandro; Giusti, Andrea; Bosi, Cristina; Malaventura, Cristina; Musso, Marco; Forni, Gian Luca; Volpato, Stefano; Zuliani, Giovanni; Borgna-Pignatti, Caterina

    2015-12-01

    Aim of this study was to compare plasma levels of the secreted protein Klotho in β-thalassemia major patients and in healthy controls. Also, we examined the existence of correlations between the protein level and osteoporosis, poor muscle strength and fractures. A total of 106 patients with β-thalassemia major and 95 healthy blood donors were enrolled. Klotho level in plasma was measured by mean of an ELISA test and the hand-grip strength using a dynamometer. Intact parathyroid hormone (PTH), 25-hydroxy vitamin D (Vitamin D), serum calcium (Ca), phosphate (P), total alkaline phosphatase (ALP), ferritin, creatinine were measured by standard clinical techniques. DXA was used to measure bone mineral density (BMD) at the lumbar spine (L2-L4), femoral neck and total hip. We found that the Klotho protein concentration was lower in the blood of patients with β-thalassemia major than in healthy controls, and it was directly correlated to the hand-grip strength. In β-thalassemia major patients, the secreted Klotho was lower than in healthy controls. The preliminary investigation into the correlation between markers of osteo- and sarcopenia and Klotho demonstrated a decreased Klotho concentration in β-TM patients and a higher probability of having had fragility fractures. PMID:26460265

  3. Nasal peak inspiratory flow at altitude.

    PubMed

    Barry, P W; Mason, N P; Richalet, J P

    2002-01-01

    The present study investigated whether there are changes in nasal peak inspiratory flow (NPIF) during hypobaric hypoxia under controlled environmental conditions. During operation Everest III (COMEX '97), eight subjects ascended to a simulated altitude of 8,848 m in a hypobaric chamber. NPIF was recorded at simulated altitudes of 0 m, 5,000 m and 8,000 m. Oral peak inspiratory and expiratory flow (OPIF, OPEF) were also measured. Ambient air temperature and humidity were controlled. NPIF increased by a mean +/- SD of 16 +/- 12% from sea level to 8,000 m, whereas OPIF increased by 47 +/- 14%. NPIF rose by 0.085 +/- 0.03 L x s(-1) per kilometre of ascent (p<0.05), significantly less than the rise in OPIF and OPEF of 0.35 +/- 0.10 and 0.33 +/- 0.04 L x s(-1) per kilometre (p<0.0005). Nasal peak inspiratory flow rises with ascent to altitude. The rise in nasal peak inspiratory flow with altitude was far less than oral peak inspiratory flow and less than the predicted rise according to changes in air density. This suggests flow limitation at the nose, and occurs under controlled environmental conditions, refuting the hypothesis that nasal blockage at altitude is due to the inhalation of cold, dry air. Further work is needed to determine if nasal blockage limits activity at altitude. PMID:11843316

  4. Laryngomalacia and inspiratory obstruction in later childhood.

    PubMed Central

    Smith, G J; Cooper, D M

    1981-01-01

    Pulmonary function and symptoms were reviewed in 20 children in whom laryngomalacia had been diagnosed by direct laryngoscopy in infancy. Most children developed stridor in the first 2 weeks, but 3 children did not develop it until age 3 months. The mean duration of stridor was 4 years 2 months, with a range of 4 months to 12 years 7 months. Six children had marked posseting as infants. Airway dynamics were assessed by flow volume loops. All except one had normal expiratory flow volume curves. Inspiratory abnormalities were detected in 7 children; 6 were assessed as having variable extrathoracic inspiratory obstructions and 1 had a fixed obstruction consistent with subglottic stenosis. The mean ratios of maximal inspiratory flow at 50% of vital capacity divided by forced vital capacity in the laryngomalacia and control groups differed significantly, as did the mean ratios of maximal expiratory flow to maximal inspiratory flow at 50% of forced vital capacity. Laryngomalacia is not necessarily a benign disorder of limited duration; there may be persisting inspiratory obstruction in later childhood. PMID:7259255

  5. Effects of training using video games on the muscle strength, muscle tone, and activities of daily living of chronic stroke patients.

    PubMed

    Lee, Gyuchang

    2013-05-01

    [Purpose] The purpose of this study was to investigate the effects of training using video games played on the Xbox Kinect on the muscle strength, muscle tone, and activities of daily living of post-stroke patients. [Subjects] Fourteen stroke patients were recruited. They were randomly allocated into two groups; the experimental group (n=7) and the control group (n=7). [Methods] The experimental group performed training using video games played on the Xbox Kinect together with conventional occupational therapy for 6 weeks (1 hour/day, 3 days/week), and the control group received conventional occupational therapy only for 6 weeks (30 min/day, 3 days/week). Before and after the intervention, the participants were measured for muscle strength, muscle tone, and performance of activities of daily living. [Results] There were significant differences pre- and post-test in muscle strength of the upper extremities, except the wrist, and performance of activities of daily living in the experimental group. There were no significant differences between the two groups at post-test. [Conclusion] The training using video games played on the Xbox Kinect had a positive effect on the motor function and performance of activities of daily living. This study showed that training using video games played on the Xbox Kinect may be an effective intervention for the rehabilitation of stroke patients. PMID:24259810

  6. Semitendinosus snapping: analysis of movement, electromyographic activities, muscle strength and endurance, motor control and joint position sense

    PubMed Central

    Guney, Hande; Kaya, Defne; Yilgor, Caglar; Cilli, Murat; Aritan, Serdar; Yuksel, Inci; Doral, Mahmut Nedim

    2013-01-01

    Summary A female ballet with a history of two-years of semi-tendinosus (ST) snapping was assessed. On physical examination snapping was observed during hyperextension of the knee. Neither any history of trauma nor treatment was recalled. Magnetic resonance imaging (MRI), movement analysis, onset timing of ST and Bisceps Femoris (BF), motor control, isokinetic muscle strength and endurance, joint position sense (JPS) were assessed. The MRI findings were normal. There were abnormal oscillations observed during hyperextension of the snapping knee compared to healthy side. There were no isokinetic muscle strength nor do muscle endurance differences. The motor control and JPS deficits were greater on the snapping knee than the healthy side. ST onset timing was earlier than BF on the snapping side. Snapping of the semitendinosus tendon has an adverse affect on JPS, motor control and onset timing of the knee muscles. PMID:24367776

  7. Bone adaptation to altered loading after spinal cord injury: a study of bone and muscle strength.

    PubMed

    Rittweger, J; Gerrits, K; Altenburg, T; Reeves, N; Maganaris, C N; de Haan, A

    2006-01-01

    Bone loss from the paralysed limbs after spinal cord injury (SCI) is well documented. Under physiological conditions, bones are adapted to forces which mainly emerge from muscle pull. After spinal cord injury (SCI), muscles can no longer contract voluntarily and are merely activated during spasms. Based on the Ashworth scale, previous research has suggested that these spasms may mitigate bone losses. We therefore wished to assess muscle forces after SCI with a more direct measure and compare it to measures of bone strength. We hypothesized that the bones in SCI patients would be in relation to the loss of muscle forces. Six male patients with SCI 6.4 (SD 4.3) years earlier and 6 age-matched, able-bodied control subjects were investigated. Bone scans from the right knee were obtained by pQCT. The knee extensor muscles were electrically stimulated via the femoral nerve, isometric knee extension torque was measured and patellar tendon force was estimated. Tendon force upon electrical stimulation in the SCI group was 75% lower than in the control subjects (p<0.01). Volumetric bone mineral density of the patella and of the proximal tibia epiphysis were 50% lower in the SCI group than in the control subjects (p<0.01). Cortical area was lower by 43% in the SCI patients at the proximal tibia metaphysis, and by 33% at the distal femur metaphysis. No group differences were found in volumetric cortical density. Close curvilinear relationships were found between stress and volumetric density for the tibia epiphysis (r(2)=0.90) and for the patella (r(2)=0.91). A weaker correlation with the tendon force was found for the cortical area of the proximal tibia metaphysis (r(2)=0.63), and none for the distal femur metaphysis. These data suggest that, under steady state conditions after SCI, epiphyseal bones are well adapted to the muscular forces. For the metaphysis of the long bones, such an adaptation appears to be less evident. The reason for this remains unclear. PMID:17142949

  8. Relation of lung function, maximal inspiratory pressure, dyspnoea, and quality of life with exercise capacity in patients with chronic obstructive pulmonary disease.

    PubMed Central

    Wijkstra, P. J.; TenVergert, E. M.; van der Mark, T. W.; Postma, D. S.; Van Altena, R.; Kraan, J.; Koëter, G. H.

    1994-01-01

    BACKGROUND--Several studies have shown that both objective and subjective measurements are related to exercise capacity in patients with chronic obstructive pulmonary disease (COPD). In this study the relative contribution of lung function, maximal inspiratory pressure, dyspnoea, and quality of life to the performance in a walking distance test and a bicycle ergometer test was investigated. METHODS--Static lung volumes, forced expiratory volume in one second (FEV1), inspiratory slow vital capacity (IVC), transfer factor for carbon monoxide (TLCO) divided by the alveolar volume (TLCO/VA), static compliance (Cst), and maximal inspiratory peak pressure (PImaxPOES) were measured in 40 patients with COPD with severe airways obstruction (mean FEV1 44% predicted, mean FEV1/IVC 37% predicted). Quality of life was assessed by the Chronic Respiratory Questionnaire (CRQ) and dyspnoea by the Borg category scale. Exercise capacity was measured by both a six minute walking distance (test) and a maximal work load of the bicycle ergometer test (Wmax). RESULTS--Spirometric values and maximal inspiratory pressure were modestly correlated with both the six minute walking test and Wmax, r values ranging from 0.50 to 0.58. The TLCO was strongly correlated with the six minute walking test (r = 0.62) and with Wmax (r = 0.78). Quality of life showed no correlation with exercise capacity, while there was a correlation between dyspnoea and the six minute walking test (r = -0.41). Backward linear regression analysis selected TLCO and PImaxPOES as the most significant determinants for exercise performance. They explained 54% and 69% of the variance in the six minute walking test and Wmax, respectively. CONCLUSIONS--The results show that exercise capacity in patients with COPD with severe airways obstruction is more strongly related to inspiratory muscle strength and lung function than to dyspnoea and quality of life. The significant correlation between dyspnoea and the six minute walking test

  9. Relationships Between Lower-Body Muscle Structure and, Lower-Body Strength, Explosiveness and Eccentric Leg Stiffness in Adolescent Athletes

    PubMed Central

    Secomb, Josh L.; Nimphius, Sophia; Farley, Oliver R.L.; Lundgren, Lina E.; Tran, Tai T.; Sheppard, Jeremy M.

    2015-01-01

    The purpose of the present study was to determine whether any relationships were present between lower-body muscle structure and, lower-body strength, variables measured during a countermovement jump (CMJ) and squat jump (SJ), and eccentric leg stiffness, in adolescent athletes. Thirty junior male (n = 23) and female (n = 7) surfing athletes (14.8 ± 1.7 y; 1.63 ± 0.09 m; 54.8 ± 12.1 kg) undertook lower-body muscle structure assessment with ultrasonography and performed a; CMJ, SJ and an isometric mid-thigh pull (IMTP). In addition, eccentric leg stiffness was calculated from variables of the CMJ and IMTP. Moderate to very large relationships (r = 0.46-0.73) were identified between the thickness of the vastus lateralis (VL) and lateral gastrocnemius (LG) muscles, and VL pennation angle and; peak force (PF) in the CMJ, SJ and IMTP. Additionally, moderate to large relationships (r = 0.37-0.59) were found between eccentric leg stiffness and; VL and LG thickness, VL pennation angle, and LG fascicle length, with a large relationship (r = 0.59) also present with IMTP PF. These results suggest that greater thickness of the VL and LG were related to improved maximal dynamic and isometric strength, likely due to increased hypertrophy of the extensor muscles. Furthermore, this increased thickness was related to greater eccentric leg stiffness, as the associated enhanced lower-body strength likely allowed for greater neuromuscular activation, and hence less compliance, during a stretch-shortening cycle. Key points Greater thickness of the VL and LG muscles were significantly related to an enhanced ability to express higher levels of isometric and dynamic strength, and explosiveness in adolescent athletes. Isometric strength underpinned performance in the CMJ and SJ in these athletes. Greater lower-body isometric strength was significantly related to eccentric leg stiffness, which is potentially the result of greater neuromuscular activation in the muscle-tendon unit. PMID

  10. The effect of training during treatment with chemotherapy on muscle strength and endurance capacity: A systematic review.

    PubMed

    Van Moll, Christel C A; Schep, Goof; Vreugdenhil, Art; Savelberg, Hans H C M; Husson, Olga

    2016-05-01

    Background Treatment of cancer with chemotherapy decreases endurance capacity and muscle strength. Training during chemotherapy might prevent this. There are no clear guidelines concerning which type of training and which training dose are effective. This review aims to gain insight into the different training modalities during chemotherapy and the effects of such training to improve endurance capacity and muscle strength in order to obtain the knowledge to compose a future training program which trains cancer patients in the most effective way. Material and methods A systematic search of PubMed was carried out. In total, 809 studies of randomized controlled trials studying the effects of training during chemotherapy on endurance capacity and muscle strength were considered. Only 14 studies met all the inclusion criteria. The studies were assessed on methodological quality by using Cochrane criteria for randomized controlled trials. Results The quality of the studies was generally poor and the study populations varied considerably as the training programs were very heterogeneous. Variables of endurance capacity reported beneficial effects in 10 groups (59%). Increases due to training ranged from 8% to 31%. Endurance capacity decreased in nine of 13 control groups (69%), which ranged from 1% to 32%. Muscle strength improved significantly in 17 of 18 intervention groups (94%), ranging from 2% to 38%. Muscle strength also improved in 11 of 14 control groups (79%), but this increase was only minimal, ranging from 1.3% to 6.5%. Conclusions This review indicates that training during chemotherapy may help in preventing the decrease in muscle strength and endurance capacity. It is important to know which training intensity and duration is the most effective in training cancer patients, to provide a training program suitable for every cancer patient. Training should be based on good research and should be implemented into international guidelines and daily practice. More

  11. Resistance training inhibits the elevation of skeletal muscle derived-BDNF level concomitant with improvement of muscle strength in zucker diabetic rat

    PubMed Central

    Kim, Hee-Jae; So, Byunghun; Son, Jun Seok; Song, Han Sol; Oh, Seung Lyul; Seong, Je Kyung; Lee, Hoyoung; Song, Wook

    2015-01-01

    [Purpose] In the present study, we investigated the effects of 8 weeks of progressive resistance training on the level of skeletal muscle derived BDNF as well as glucose intolerance in Zucker diabetic rats. [Methods] Six week-old male Zucker diabetic fatty (ZDF) and Zucker lean control (ZLC) rats were randomly divided into 3 groups: sedentary ZLC (ZLC-Con), sedentary ZDF (ZDF-Con), and exercised ZDF (ZDF-Ex). Progressive resistance training using a ladder and tail weights was performed for 8 weeks (3 days/week). [Results] After 8 weeks of resistance training, substantial reduction in body weight was observed in ZDF-Ex compared to ZDF-Con. Though the skeletal muscle volume did not change, grip strength grip strength was significantly higher in ZDF-Ex compared to ZDF-Con. In the soleus, the level of BDNF was increased in ZDF-Con, but was significantly decreased (p<0.05) in ZDF-Ex, showing a training effect. Moreover, we found that there was a negative correlation (r=-0.657; p=0.004) between grip strength and BDNF level whereas there was a positive correlation (r=0.612; p=0.008) between plasma glucose level and BDNF level in skeletal muscle. [Conclusion] Based upon our results, we demonstrated that resistance training inhibited the elevation of skeletal muscle derived-BDNF expression concomitant with the improvement of muscle strength in zucker diabetic rats. In addition, muscle-derived BDNF might be a potential mediator for the preventive effect of resistance training on the progress of type 2 diabetes. PMID:27274460

  12. The effect of hip abductor exercise on muscle strength and trunk stability after an injury of the lower extremities

    PubMed Central

    Kak, Hwang-Bo; Park, Sun-Ja; Park, Byun-Joon

    2016-01-01

    [Purpose] The gluteus medius, a hip abductor, controls femoral movement and stabilizes the pelvis during lower extremity mobilization. [Subjects] This study enrolled 24 subjects into control and experimental groups. [Methods] This randomized controlled study included patients who underwent arthroscopy after meniscus injury and started a rehabilitative exercise program 8 weeks after surgery. Subjects were divided into the experimental gluteus medius resistance exercise group (n=12) and the control group (n=12). The study investigated muscle strength and balance of the flexors, extensors, and abductors of the knee for 8 weeks. [Results] Strengths of knee extensors in patients who underwent rehabilitative exercise for 8 weeks were measured. Strength of the knee extensors of the experimental and control groups increased by 40% and 31%, respectively; strength of the hip flexors of the experimental and control groups increased by 31% and 18%, respectively. Strength of the hip joint muscles showed a 40% increase in the experimental group and a 14% increase in the control group. However, there was a significant difference (18%) in muscle strength of the hip abductors between the groups. Measurements of trunk lateral flexion showed a difference within a group, but no intergroup difference was found. [Conclusion] This study investigated the effect of hip abductor exercise on muscular strength and trunk stability in patients with a meniscus injury. PMID:27134387

  13. Seropositivity for CMV and IL-6 levels are associated with grip strength and muscle size in the elderly

    PubMed Central

    2013-01-01

    Background Sarcopenia is an important cause of morbidity and mortality in older adults, with immunosenescence and inflammation being possible underlying mechanisms. We investigated the relationship between latent cytomegalovirus (CMV) infection, Interleukin 6 (IL-6) levels, muscle size and strength in a group of healthy older community-dwelling people. Methods Participants were healthy volunteers from the Lothian Birth Cohort 1936 study. Participants had IL-6 level and CMV antibody titre measured at age 70 years and grip strength and a volumetric T1-weighted MRI brain scan (allowing measurement of neck muscle cross-sectional area (CSA)) at age 73. Markers of childhood deprivation were adjusted for in the analysis due to correlations between childhood deprivation and latent CMV infection. Results 866 participants were studied; 448 men (mean age 72.48 years, sd 0.70) and 418 women (mean age 72.51 years, sd 0.72). In men, CMV seropositivity was associated with smaller neck muscle CSA (p = 0.03, partial eta squared = 0.01), even after adjustment for IL-6 levels. Neck muscle CSA was not associated with CMV seropositivity in women, or CMV antibody titre or IL-6 level in either sex. Grip strength associated negatively with IL-6 level (right grip strength p<0.00001, partial eta squared 0.032 and left grip strength p<0.00001, partial eta squared 0.027) with or without adjustment for CMV serostatus or antibody titre. CMV status and antibody titre were not significantly associated with grip strength in either hand. Conclusion These findings support the hypothesis that there is a relationship between markers of immunosenescence (i.e. CMV serostatus and IL6 level) and low muscle mass and strength and longitudinal studies in older cohorts are now required to investigate these relationships further. PMID:23938060

  14. The effect of exercise-induced muscle damage on isometric and dynamic knee extensor strength and vertical jump performance.

    PubMed

    Byrne, Christopher; Eston, Roger

    2002-05-01

    In this study, we assessed the effect of exercise-induced muscle damage on knee extensor muscle strength during isometric, concentric and eccentric actions at 1.57 rad x s(-1) and vertical jump performance under conditions of squat jump, countermovement jump and drop jump. The eight participants (5 males, 3 females) were aged 29.5+/-7.1 years (mean +/- s). These variables, together with plasma creatine kinase (CK), were measured before, 1 h after and 1, 2, 3, 4 and 7 days after a bout of muscle damaging exercise: 100 barbell squats (10 sets x 10 repetitions at 70% body mass load). Strength was reduced for 4 days (P< 0.05) but no significant differences (P> 0.05) were apparent in the magnitude or rate of recovery of strength between isometric, concentric and eccentric muscle actions. The overall decline in vertical jump performance was dependent on jump method: squat jump performance was affected to a greater extent than countermovement (91.6+/-1.1% vs 95.2+/-1.3% of pre-exercise values, P< 0.05) and drop jump (95.2+/-1.4%, P< 0.05) performance. Creatine kinase was elevated (P < 0.05) above baseline 1 h after exercise, peaked on day 1 and remained significantly elevated on days 2 and 3. Strength loss after exercise-induced muscle damage was independent of the muscle action being performed. However, the impairment of muscle function was attenuated when the stretch-shortening cycle was used in vertical jumping performance. PMID:12043831

  15. Early Neuromuscular Electrical Stimulation to Improve Quadriceps Muscle Strength After Total Knee Arthroplasty: A Randomized Controlled Trial

    PubMed Central

    Balter, Jaclyn E.; Wolfe, Pamela; Eckhoff, Donald G.; Kohrt, Wendy M.

    2012-01-01

    Background The recovery of quadriceps muscle force and function after total knee arthroplasty (TKA) is suboptimal, which predisposes patients to disability with increasing age. Objective The purpose of this investigation was to evaluate the efficacy of quadriceps muscle neuromuscular electrical stimulation (NMES), initiated 48 hours after TKA, as an adjunct to standard rehabilitation. Design This was a prospective, longitudinal randomized controlled trial. Methods Sixty-six patients, aged 50 to 85 years and planning a primary unilateral TKA, were randomly assigned to receive either standard rehabilitation (control) or standard rehabilitation plus NMES applied to the quadriceps muscle (initiated 48 hours after surgery). The NMES was applied twice per day at the maximum tolerable intensity for 15 contractions. Data for muscle strength, functional performance, and self-report measures were obtained before surgery and 3.5, 6.5, 13, 26, and 52 weeks after TKA. Results At 3.5 weeks after TKA, significant improvements with NMES were found for quadriceps and hamstring muscle strength, functional performance, and knee extension active range of motion. At 52 weeks, the differences between groups were attenuated, but improvements with NMES were still significant for quadriceps and hamstring muscle strength, functional performance, and some self-report measures. Limitations Treatment volume was not matched for both study arms; NMES was added to the standard of care treatment. Furthermore, testers were not blinded during testing, but used standardized scripts to avoid bias. Finally, some patients reached the maximum stimulator output during at least one treatment session and may have tolerated more stimulation. Conclusions The early addition of NMES effectively attenuated loss of quadriceps muscle strength and improved functional performance following TKA. The effects were most pronounced and clinically meaningful within the first month after surgery, but persisted through 1

  16. COMPETITIVE ATHLETIC PARTICIPATION, THIGH MUSCLE STRENGTH, AND BONE DENSITY IN ELITE SENIOR ATHLETES AND CONTROLS

    PubMed Central

    McCrory, Jean L.; Salacinski, Amanda J.; Hunt Sellhorst, Sarah E.; Greenspan, Susan L.

    2016-01-01

    The relationship between participation in highly competitive exercise, thigh muscle strength, and regional and total body bone mineral density (BMD) in elite senior athletes and healthy elderly controls was investigated. One hundred and four elite senior athletes (72.6±6.4yrs, 168.7±8.6cm, 72.6±13.5kg, 57M:47F) and 79 healthy controls (75.4±5.6yrs, 170.8±25.5cm, 79.5± 11.7kg, 46M:33F) participated in this cross-sectional study. Vitamin D and calcium intake were assessed via a recall survey. Isometric knee extension and flexion peak torque was measured via a custom strength measurement device. Total body and regional BMD of the hip, radius, and spine were assessed with DXA. For each BMD site assessed, multivariate linear regression analysis was performed in four steps (α=0.10) to examine the contribution of (1) age, sex, bodyweight, and calcium and vitamin D intake (2) group (elite senior athlete, control), (3) knee extension peak torque and (4) knee flexion peak torque on BMD. Sex, age, bodyweight, and calcium and vitamin D intake explained a significant amount of variance in BMD in each site. Group was not significant. Knee extension peak torque explained an additional 3.8% of the variance in hip BMD (p=0.06). Knee flexion peak torque was not correlated to BMD at any of the sites assessed. In conclusion, participation in highly competitive athletics was not related to total body or regional BMD. Age, sex, bodyweight, and vitamin D and calcium intake were significantly related to BMD at all of the sites assessed. Quadriceps strength contributed slightly to hip BMD. Our results imply that participation in highly competitive senior athletics does not have a protective effect on BMD, perhaps because of a lower bodyweight or other confounding factors. PMID:23442279

  17. [Recovery of muscle contractility after a strength training session: mechanical, neurophysiologic and biochemical approach].

    PubMed

    Michaut, A; Pousson, M; Belleville, J; Van Hoecke, J

    1998-01-01

    The purpose of this study was to observe the recovery of maximal strength immediately after a maximal eccentric strength training set. The trained female subjects (n = 8) performed 10 bouts of 10 maximal eccentric contractions of the quadriceps muscle. Each bout was separated by a 2 minutes rest period. Integrated electromyogram (iEMG) of the vastus medialis and the rectus femoris, and torque were measured before, just after, 24 and 48 hours after training session, at different knee angular velocity (-60, 0, 60, 120, and 240 degrees.s-1). Possible structural damage of the muscular cell were searched from the urinary concentration of some protein catabolism metabolites before (basal rate), 24 and 48 hours after the exercise. Maximal torque significantly fell for any angular velocity immediately after the training session: 13.6% at -60 degrees.s-1, 16.9% at 60 degrees.s-1, 7.5% at 120 degrees.s-1, 12.8% at 240 degrees.s-1 and 8.6% at 0 degree.s-1. This event was accompanied by an increase of the iEMG at the training angular speed, and by an increase of the metabolites concentration in a half part of the subjects. Strength developed during eccentric contraction showed the earliest recovery. And it even significantly overshot its initial level by 14.9% at 48 hours. A significant increase of the iEMG assessed at the eccentric velocity was then observed. In the same time, 3 of the 6 subjects showed an increase of their urinary concentration of the chosen metabolites in comparison with their initial values. This result may closely be connected with the supercompensation phenomenon, which first appears in the training mode. This phenomenon could partly be explained by the associated increase of the iEMG. PMID:9759363

  18. Acute effects of different inspiratory efforts on ventilatory pattern and chest wall compartmental distribution in elderly women.

    PubMed

    Muniz de Souza, Helga; Rocha, Taciano; Campos, Shirley Lima; Brandão, Daniella Cunha; Fink, James B; Aliverti, Andrea; de Andrade, Armele Dornelas

    2016-06-15

    It is not completely described how aging affect ventilatory kinematics and what are the mechanisms adopted by the elderly population to overcome these structural modifications. Given this, the aim was to evaluate the acute effects of different inspiratory efforts on ventilatory pattern and chest wall compartmental distribution in elderly women. Variables assessed included: tidal volume (Vt), total chest wall volume (Vcw), pulmonary rib cage (Vrcp%), abdominal rib cage (Vrca%) and abdominal compartment (Vab%) relative contributions to tidal volume. These variables were assessed during quiet breathing, maximal inspiratory pressure maneuver (MIP), and moderate inspiratory resistance (MIR; i.e., 40% of MIP). 22 young women (age: 23.9±2.5 years) and 22 elderly women (age: 68.2±5.0 years) participated to this study. It was possible to show that during quiet breathing, Vab% was predominant in elderly (p<0.001), in young, however, Vab% was similar to Vrcp% (p=0.095). During MIR, Vrcp% was predominant in young (p<0.001) and comparable to Vab% in elderly (p=0.249). When MIP was imposed, both groups presented a predominance of Vrcp%. In conclusion, there are differences in abdominal kinematics between young and elderly women during different inspiratory efforts. In elderly, during moderate inspiratory resistance, the pattern is beneficial, deep, and slow. Although, during maximal inspiratory resistance, the ventilatory pattern seems to predict imminent muscle fatigue. PMID:26900004

  19. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  20. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  1. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  2. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  3. Acute Effects of Different Methods of Stretching and Specific Warm-ups on Muscle Architecture and Strength Performance.

    PubMed

    Sá, Marcos A; Matta, Thiago T; Carneiro, Simone P; Araujo, Carolina O; Novaes, Jefferson S; Oliveira, Liliam F

    2016-08-01

    Sá, MA, Matta, TT, Carneiro, SP, Araujo, CO, Novaes, JS, and Oliveira, LF. Acute effects of different methods of stretching and specific warm-ups on muscle architecture and strength performance. J Strength Cond Res 30(8): 2324-2329, 2016-The purpose of the study was to investigate the acute effects of 2 stretching interventions, proprioceptive neuromuscular facilitation (PNF) and passive static stretching (PSS), and a specific warm-up (SW) on the strength and architecture of the vastus laterallis and biceps femoris muscles in a subsequent performance on a strength training session (STS). Musculoskeletal ultrasound images were acquired from 9 men before and immediately after stretchings or a SW, and 10 minutes after a STS. The STS consisted of the following exercises: leg extension, leg curl, leg press, and hack machine squat. The PNF resulted in lower performance for all situations. The PSS and SW improved performance for the leg press compared with the PNF and controls (CSs). For the hack machine squat, SWs resulted in higher performance than stretching conditions. The vastus lateralis muscle fascicle length (FL) increases after a STS for PNF. The biceps femoris muscle showed a higher pennation angle 10 minutes after the STS for PSS; the FL increases immediately after PSS and then decreases 10 minutes after the STS for PSS. As per our results, the SWs should be performed before STSs, whereas PNF stretching should not be prescribed because this condition impairs subsequent performance. These results may assist health professionals in prescribing resistance training. PMID:26705067

  4. Bone Mineral Density and Respiratory Muscle Strength in Male Individuals with Mental Retardation (with and without Down Syndrome)

    ERIC Educational Resources Information Center

    da Silva, Vinicius Zacarias Maldaner; Barros, Jonatas de Franca; de Azevedo, Monique; de Godoy, Jose Roberto Pimenta; Arena, Ross; Cipriano, Gerson, Jr.

    2010-01-01

    The purpose of this study was to assess the respiratory muscle strength (RMS) in individuals with mental retardation (MR), with or without Down Syndrome (DS), and its association with bone mineral density (BMD). Forty-five male individuals (15 with DS, 15 with mental retardation (MR) and 15 apparently healthy controls), aged 20-35, participated in…

  5. Increases in muscle strength and balance using a resistance training program administered via a telecommunications system in older adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: Resistance training programs have been found to improve muscle strength, physical function, and depressive symptoms in middle-aged and older adults. These programs have typically been provided in clinical facilities, health clubs, and senior centers, which may be inconvenient and/or cos...

  6. To What Extent Is Mean EMG Frequency during Gait a Reflection of Functional Muscle Strength in Children with Cerebral Palsy?

    ERIC Educational Resources Information Center

    Van Gestel, L.; Wambacq, H.; Aertbelien, E.; Meyns, P.; Bruyninckx, H.; Bar-On, L.; Molenaers, G.; De Cock, P.; Desloovere, K.

    2012-01-01

    The aim of the current paper was to analyze the potential of the mean EMG frequency, recorded during 3D gait analysis (3DGA), for the evaluation of functional muscle strength in children with cerebral palsy (CP). As walking velocity is known to also influence EMG frequency, it was investigated to which extent the mean EMG frequency is a reflection…

  7. Knee Muscle Strength at Varying Angular Velocities and Associations with Gross Motor Function in Ambulatory Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Hong, Wei-Hsien; Chen, Hseih-Ching; Shen, I-Hsuan; Chen, Chung-Yao; Chen, Chia-Ling; Chung, Chia-Ying

    2012-01-01

    The aim of this study was to evaluate the relationships of muscle strength at different angular velocities and gross motor functions in ambulatory children with cerebral palsy (CP). This study included 33 ambulatory children with spastic CP aged 6-15 years and 15 children with normal development. Children with CP were categorized into level I (n =…

  8. Review of Modelling Techniques for In Vivo Muscle Force Estimation in the Lower Extremities during Strength Training

    PubMed Central

    Schellenberg, Florian; Oberhofer, Katja; Taylor, William R.; Lorenzetti, Silvio

    2015-01-01

    Background. Knowledge of the musculoskeletal loading conditions during strength training is essential for performance monitoring, injury prevention, rehabilitation, and training design. However, measuring muscle forces during exercise performance as a primary determinant of training efficacy and safety has remained challenging. Methods. In this paper we review existing computational techniques to determine muscle forces in the lower limbs during strength exercises in vivo and discuss their potential for uptake into sports training and rehabilitation. Results. Muscle forces during exercise performance have almost exclusively been analysed using so-called forward dynamics simulations, inverse dynamics techniques, or alternative methods. Musculoskeletal models based on forward dynamics analyses have led to considerable new insights into muscular coordination, strength, and power during dynamic ballistic movement activities, resulting in, for example, improved techniques for optimal performance of the squat jump, while quasi-static inverse dynamics optimisation and EMG-driven modelling have helped to provide an understanding of low-speed exercises. Conclusion. The present review introduces the different computational techniques and outlines their advantages and disadvantages for the informed usage by nonexperts. With sufficient validation and widespread application, muscle force calculations during strength exercises in vivo are expected to provide biomechanically based evidence for clinicians and therapists to evaluate and improve training guidelines. PMID:26417378

  9. Submental sEMG and Hyoid Movement during Mendelsohn Maneuver, Effortful Swallow, and Expiratory Muscle Strength Training

    ERIC Educational Resources Information Center

    Wheeler-Hegland, Karen M.; Rosenbek, John C.; Sapienza, Christine M.

    2008-01-01

    Purpose: This study investigated the concurrent biomechanical and electromyographic properties of 2 swallow-specific tasks (effortful swallow and Mendelsohn maneuver) and 1 swallow-nonspecific (expiratory muscle strength training [EMST]) swallow therapy task in order to examine the differential effects of each on hyoid motion and associated…

  10. Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area.

    PubMed

    Lin, Fuxin; Zhao, Bing; Wu, Jun; Wang, Lijun; Jin, Zhen; Cao, Yong; Wang, Shuo

    2016-08-01

    OBJECT Case selection for the surgical treatment of arteriovenous malformations (AVMs) of the eloquent motor area remains challenging. The aim of this study was to determine the risk factors for worsened muscle strength after surgery in patients with this disorder. METHODS At their hospital the authors retrospectively studied 48 consecutive patients with AVMs involving motor cortex and/or the descending pathway. All patients had undergone preoperative functional MRI (fMRI) and diffusion tensor imaging (DTI), followed by resection. Both functional and angioarchitectural factors were analyzed with respect to the change in muscle strength. Functional factors included lesion-to-corticospinal tract distance (LCD) on DTI and lesion-to-activation area distance (LAD) and cortical reorganization on fMRI. Based on preoperative muscle strength, the changes in muscle strength at 1 week and 6 months after surgery were defined as short-term and long-term surgical outcomes, respectively. Statistical analysis was performed using the statistical package SPSS (version 20.0.0, IBM Corp.). RESULTS Twenty-one patients (43.8%) had worsened muscle strength 1 week after surgery. However, only 10 patients (20.8%) suffered from muscle strength worsening 6 months after surgery. The LCD was significantly correlated with short-term (p < 0.001) and long-term (p < 0.001) surgical outcomes. For long-term outcomes, patients in the 5 mm ≥ LCD > 0 mm (p = 0.009) and LCD > 5 mm (p < 0.001) categories were significantly associated with a lower risk of permanent motor worsening in comparison with patients in the LCD = 0 mm group. No significant difference was found between patients in the 5 mm ≥ LCD > 0 mm group and LCD > 5 mm group (p = 0.116). Nidus size was the other significant predictor of short-term (p = 0.021) and long-term (p = 0.016) outcomes. For long-term outcomes, the area under the ROC curve (AUC) was 0.728, and the cutoff point was 3.6 cm. Spetzler-Martin grade was not associated with

  11. Psychosocial correlates of cardiorespiratory fitness and muscle strength in overweight and obese post-menopausal women: a MONET study.

    PubMed

    Karelis, Antony D; Fontaine, Jonathan; Messier, Virginie; Messier, Lyne; Blanchard, Chris; Rabasa-Lhoret, Remi; Strychar, Irene

    2008-07-01

    The purpose of this study was to examine the psychosocial correlates of cardiorespiratory fitness (VO2peak) and muscle strength in overweight and obese sedentary post-menopausal women. The study population consisted of 137 non-diabetic, sedentary overweight and obese post-menopausal women (mean age 57.7 years, s = 4.8; body mass index 32.4 kg.m(-2), s = 4.6). At baseline we measured: (1) body composition using dual-energy X-ray absorptiometry; (2) visceral fat using computed tomography; (3) insulin sensitivity using the hyperinsulinaemic-euglycaemic clamp; (4) cardiorespiratory fitness; (5) muscle strength using the leg press exercise; and (6) psychosocial profile (quality of life, perceived stress, self-esteem, body-esteem, and perceived risk for developing chronic diseases) using validated questionnaires. Both VO2peak and muscle strength were significantly correlated with quality of life (r = 0.29, P < 0.01 and r = 0.30, P < 0.01, respectively), and quality of life subscales for: physical functioning (r = 0.28, P < 0.01 and r = 0.22, P < 0.05, respectively), pain (r = 0.18, P < 0.05 and r = 0.23, P < 0.05, respectively), role functioning (r = 0.20, P < 0.05 and r = 0.24, P < 0.05, respectively), and perceived risks (r = -0.24, P < 0.01 and r = -0.30, P < 0.01, respectively). In addition, VO2peak was significantly associated with positive health perceptions, greater body esteem, and less time watching television/video. Stepwise regression analysis showed that quality of life for health perceptions and for role functioning were independent predictors of VO2peak and muscle strength, respectively. In conclusion, higher VO2peak and muscle strength are associated with a favourable psychosocial profile, and the psychosocial correlates of VO2peak were different from those of muscle strength. Furthermore, psychosocial factors could be predictors of VO2peak and muscle strength in our cohort of overweight and obese sedentary post-menopausal women. PMID:18569559

  12. Assessment of Lower Limb Muscle Strength and Power Using Hand-Held and Fixed Dynamometry: A Reliability and Validity Study

    PubMed Central

    Perraton, Luke G.; Bower, Kelly J.; Adair, Brooke; Pua, Yong-Hao; Williams, Gavin P.; McGaw, Rebekah

    2015-01-01

    Introduction Hand-held dynamometry (HHD) has never previously been used to examine isometric muscle power. Rate of force development (RFD) is often used for muscle power assessment, however no consensus currently exists on the most appropriate method of calculation. The aim of this study was to examine the reliability of different algorithms for RFD calculation and to examine the intra-rater, inter-rater, and inter-device reliability of HHD as well as the concurrent validity of HHD for the assessment of isometric lower limb muscle strength and power. Methods 30 healthy young adults (age: 23±5yrs, male: 15) were assessed on two sessions. Isometric muscle strength and power were measured using peak force and RFD respectively using two HHDs (Lafayette Model-01165 and Hoggan microFET2) and a criterion-reference KinCom dynamometer. Statistical analysis of reliability and validity comprised intraclass correlation coefficients (ICC), Pearson correlations, concordance correlations, standard error of measurement, and minimal detectable change. Results Comparison of RFD methods revealed that a peak 200ms moving window algorithm provided optimal reliability results. Intra-rater, inter-rater, and inter-device reliability analysis of peak force and RFD revealed mostly good to excellent reliability (coefficients ≥ 0.70) for all muscle groups. Concurrent validity analysis showed moderate to excellent relationships between HHD and fixed dynamometry for the hip and knee (ICCs ≥ 0.70) for both peak force and RFD, with mostly poor to good results shown for the ankle muscles (ICCs = 0.31–0.79). Conclusions Hand-held dynamometry has good to excellent reliability and validity for most measures of isometric lower limb strength and power in a healthy population, particularly for proximal muscle groups. To aid implementation we have created freely available software to extract these variables from data stored on the Lafayette device. Future research should examine the reliability

  13. IMPACT OF BACK MUSCLE STRENGTH AND AGING ON LOCOMOTIVE SYNDROME IN COMMUNITY LIVING JAPANESE WOMEN

    PubMed Central

    HIRANO, KENICHI; IMAGAMA, SHIRO; HASEGAWA, YUKIHARU; WAKAO, NORIMITSU; MURAMOTO, AKIO; ISHIGURO, NAOKI

    2013-01-01

    ABSTRACT The Japanese Orthopaedic Association has proposed the term locomotive syndrome (LS) to designate a condition of individuals in high-risk groups with musculoskeletal disease who are highly likely to require nursing care. This study investigates the influence of spinal factors on LS in Japanese females. A total of 187 women >50 years old were enrolled in the study. Those answering yes to least one of the 7 categories in the self-assessment checklist for LS were defined as having LS. We evaluated lateral lumbar radiographs, sagittal parameters, sagittal balance using the spinal inclination angle (SIA) as an index, spinal range of motion (ROM) as determined with SpinalMouse®, back muscle strength (BMS), and body mass index (BMI). Age, BMI, BMS, SIA, sacral slope angle (SSA), and lumbar spinal ROM showed significant correlations with LS. Multiple logistic regression analysis indicated that an increase in age (OR 1.054, p<0.05) and a decrease in BMS (OR 0.968, p<0.01) were significantly associated with LS. Age had significant negative correlations with BMS, SSA, thoracic and lumbar spinal ROM, and it had positive correlations with BMI, SIA, and lumbar kyphosis. BMS had significant negative correlations with age, SIA, thoracic and lumbar kyphosis, and it had positive correlations with SSA, lumbar and total spinal ROM. An increase in age and a decrease in BMS may be the most important risk factors for LS in Japanese women. Back muscle strengthening and spinal ROM exercises could be useful for improving the status of an individual suffering from LS. PMID:23544268

  14. Six-minute walk test and respiratory muscle strength in patients with uncontrolled severe asthma: a pilot study*

    PubMed Central

    Pereira, Luiz Fernando Ferreira; Mancuzo, Eliane Viana; Rezende, Camila Farnese; Côrrea, Ricardo de Amorim

    2015-01-01

    OBJECTIVE: To evaluate respiratory muscle strength and six-minute walk test (6MWT) variables in patients with uncontrolled severe asthma (UCSA). METHODS: This was a cross-sectional study involving UCSA patients followed at a university hospital. The patients underwent 6MWT, spirometry, and measurements of respiratory muscle strength, as well as completing the Asthma Control Test (ACT). The Mann-Whitney test was used in order to analyze 6MWT variables, whereas the Kruskal-Wallis test was used to determine whether there was an association between the use of oral corticosteroids and respiratory muscle strength. RESULTS: We included 25 patients. Mean FEV1 was 58.8 ± 21.8% of predicted, and mean ACT score was 14.0 ± 3.9 points. No significant difference was found between the median six-minute walk distance recorded for the UCSA patients and that predicted for healthy Brazilians (512 m and 534 m, respectively; p = 0.14). During the 6MWT, there was no significant drop in SpO2. Mean MIP and MEP were normal (72.9 ± 15.2% and 67.6 ± 22.2%, respectively). Comparing the patients treated with at least four courses of oral corticosteroids per year and those treated with three or fewer, we found no significant differences in MIP (p = 0.15) or MEP (p = 0.45). CONCLUSIONS: Our findings suggest that UCSA patients are similar to normal subjects in terms of 6MWT variables and respiratory muscle strength. The use of oral corticosteroids has no apparent impact on respiratory muscle strength. PMID:26176518

  15. Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training.

    PubMed

    Roberts, Llion A; Raastad, Truls; Markworth, James F; Figueiredo, Vandre C; Egner, Ingrid M; Shield, Anthony; Cameron-Smith, David; Coombes, Jeff S; Peake, Jonathan M

    2015-09-15

    We investigated functional, morphological and molecular adaptations to strength training exercise and cold water immersion (CWI) through two separate studies. In one study, 21 physically active men strength trained for 12 weeks (2 days per week), with either 10 min of CWI or active recovery (ACT) after each training session. Strength and muscle mass increased more in the ACT group than in the CWI group (P < 0.05). Isokinetic work (19%), type II muscle fibre cross-sectional area (17%) and the number of myonuclei per fibre (26%) increased in the ACT group (all P < 0.05), but not the CWI group. In another study, nine active men performed a bout of single-leg strength exercises on separate days, followed by CWI or ACT. Muscle biopsies were collected before and 2, 24 and 48 h after exercise. The number of satellite cells expressing neural cell adhesion molecule (NCAM) (10-30%) and paired box protein (Pax7) (20-50%) increased 24-48 h after exercise with ACT. The number of NCAM(+) satellite cells increased 48 h after exercise with CWI. NCAM(+) - and Pax7(+) -positive satellite cell numbers were greater after ACT than after CWI (P < 0.05). Phosphorylation of p70S6 kinase(Thr421/Ser424) increased after exercise in both conditions but was greater after ACT (P < 0.05). These data suggest that CWI attenuates the acute changes in satellite cell numbers and activity of kinases that regulate muscle hypertrophy, which may translate to smaller long-term training gains in muscle strength and hypertrophy. The use of CWI as a regular post-exercise recovery strategy should be reconsidered. PMID:26174323

  16. Calmodulin Methyltransferase Is Required for Growth, Muscle Strength, Somatosensory Development and Brain Function.

    PubMed

    Haziza, Sitvanit; Magnani, Roberta; Lan, Dima; Keinan, Omer; Saada, Ann; Hershkovitz, Eli; Yanay, Nurit; Cohen, Yoram; Nevo, Yoram; Houtz, Robert L; Sheffield, Val C; Golan, Hava; Parvari, Ruti

    2015-08-01

    Calmodulin lysine methyl transferase (CaM KMT) is ubiquitously expressed and highly conserved from plants to vertebrates. CaM is frequently trimethylated at Lys-115, however, the role of CaM methylation in vertebrates has not been studied. CaM KMT was found to be homozygously deleted in the 2P21 deletion syndrome that includes 4 genes. These patients present with cystinuria, severe intellectual disabilities, hypotonia, mitochondrial disease and facial dysmorphism. Two siblings with deletion of three of the genes included in the 2P21 deletion syndrome presented with cystinuria, hypotonia, a mild/moderate mental retardation and a respiratory chain complex IV deficiency. To be able to attribute the functional significance of the methylation of CaM in the mouse and the contribution of CaM KMT to the clinical presentation of the 2p21deletion patients, we produced a mouse model lacking only CaM KMT with deletion borders as in the human 2p21deletion syndrome. No compensatory activity for CaM methylation was found. Impairment of complexes I and IV, and less significantly III, of the mitochondrial respiratory chain was more pronounced in the brain than in muscle. CaM KMT is essential for normal body growth and somatosensory development, as well as for the proper functioning of the adult mouse brain. Developmental delay was demonstrated for somatosensory function and for complex behavior, which involved both basal motor function and motivation. The mutant mice also had deficits in motor learning, complex coordination and learning of aversive stimuli. The mouse model contributes to the evaluation of the role of methylated CaM. CaM methylation appears to have a role in growth, muscle strength, somatosensory development and brain function. The current study has clinical implications for human patients. Patients presenting slow growth and muscle weakness that could result from a mitochondrial impairment and mental retardation should be considered for sequence analysis of the Ca

  17. Calmodulin Methyltransferase Is Required for Growth, Muscle Strength, Somatosensory Development and Brain Function

    PubMed Central

    Haziza, Sitvanit; Magnani, Roberta; Lan, Dima; Keinan, Omer; Saada, Ann; Hershkovitz, Eli; Yanay, Nurit; Cohen, Yoram; Nevo, Yoram; Houtz, Robert L.; Sheffield, Val C.; Golan, Hava; Parvari, Ruti

    2015-01-01

    Calmodulin lysine methyl transferase (CaM KMT) is ubiquitously expressed and highly conserved from plants to vertebrates. CaM is frequently trimethylated at Lys-115, however, the role of CaM methylation in vertebrates has not been studied. CaM KMT was found to be homozygously deleted in the 2P21 deletion syndrome that includes 4 genes. These patients present with cystinuria, severe intellectual disabilities, hypotonia, mitochondrial disease and facial dysmorphism. Two siblings with deletion of three of the genes included in the 2P21 deletion syndrome presented with cystinuria, hypotonia, a mild/moderate mental retardation and a respiratory chain complex IV deficiency. To be able to attribute the functional significance of the methylation of CaM in the mouse and the contribution of CaM KMT to the clinical presentation of the 2p21deletion patients, we produced a mouse model lacking only CaM KMT with deletion borders as in the human 2p21deletion syndrome. No compensatory activity for CaM methylation was found. Impairment of complexes I and IV, and less significantly III, of the mitochondrial respiratory chain was more pronounced in the brain than in muscle. CaM KMT is essential for normal body growth and somatosensory development, as well as for the proper functioning of the adult mouse brain. Developmental delay was demonstrated for somatosensory function and for complex behavior, which involved both basal motor function and motivation. The mutant mice also had deficits in motor learning, complex coordination and learning of aversive stimuli. The mouse model contributes to the evaluation of the role of methylated CaM. CaM methylation appears to have a role in growth, muscle strength, somatosensory development and brain function. The current study has clinical implications for human patients. Patients presenting slow growth and muscle weakness that could result from a mitochondrial impairment and mental retardation should be considered for sequence analysis of the Ca

  18. Changes in muscle strength and pain in response to surgical repair of posterior abdominal wall disruption followed by rehabilitation

    PubMed Central

    Hemingway, A; Herrington, L; Blower, A

    2003-01-01

    Background: Posterior abdominal wall deficiency (PAWD) is a tear in the external oblique aponeurosis or the conjoint tendon causing a posterior wall defect at the medial end of the inguinal canal. It is often known as sportsman's hernia and is believed to be caused by repetitive stress. Objective: To assess lower limb and abdominal muscle strength of patients with PAWD before intervention compared with matched controls; to evaluate any changes following surgical repair and rehabilitation. Methods: Sixteen subjects were assessed using a questionnaire, isokinetic testing of the lower limb strength, and pressure biofeedback testing of the abdominals. After surgery and a six week rehabilitation programme, the subjects were re-evaluated. A control group were assessed using the same procedure. Results: Quadriceps and hamstrings strength was not affected by this condition. A deficit hip muscle strength was found on the affected limb before surgery, which was significant for the hip flexors (p = 0.05). Before surgery, 87% of the patients compared with 20% of the controls failed the abdominal obliques test. Both the injured and non-injured sides had improved significantly in strength after surgery and rehabilitation. The strength of the abdominal obliques showed the most significant improvement over the course of the rehabilitation programme. Conclusions: Lower limb muscle strength may have been reduced as the result of disuse atrophy or pain inhibition. Abdominal oblique strength was deficient in the injured patients and this compromises rotational control of the pelvis. More sensitive investigations (such as electromyography) are needed to assess the link between abdominal oblique function and groin injury. PMID:12547744

  19. Glucocorticoid Receptor (NR3C1) Variants Associate with the Muscle Strength and Size Response to Resistance Training

    PubMed Central

    Ash, Garrett I.; Kostek, Matthew A.; Lee, Harold; Angelopoulos, Theodore J.; Gordon, Paul M.; Moyna, Niall M.; Visich, Paul S.; Zoeller, Robert F.; Price, Thomas B.; Devaney, Joseph M.; Gordish-Dressman, Heather; Thompson, Paul D.; Hoffman, Eric P.; Pescatello, Linda S.

    2016-01-01

    Glucocorticoid receptor (NR3C1) polymorphisms associate with obesity, muscle strength, and cortisol sensitivity. We examined associations among four NR3C1 polymorphisms and the muscle response to resistance training (RT). European-American adults (n = 602, 23.8±0.4yr) completed a 12 week unilateral arm RT program. Maximum voluntary contraction (MVC) assessed isometric strength (kg) and MRI assessed biceps size (cm2) pre- and post-resistance training. Subjects were genotyped for NR3C1 -2722G>A, -1887G>A, -1017T>C, and +363A>G. Men carrying the -2722G allele gained less relative MVC (17.3±1.2vs33.5±6.1%) (p = 0.010) than AA homozygotes; men with -1887GG gained greater relative MVC than A allele carriers (19.6±1.4vs13.2±2.3%) (p = 0.016). Women carrying the -1017T allele gained greater relative size (18.7±0.5vs16.1±0.9%) (p = 0.016) than CC homozygotes. We found sex-specific NR3C1 associations with the muscle strength and size response to RT. Future studies should investigate whether these associations are partially explained by cortisol’s actions in muscle tissue as they interact with sex differences in cortisol production. PMID:26821164

  20. Glucocorticoid Receptor (NR3C1) Variants Associate with the Muscle Strength and Size Response to Resistance Training.

    PubMed

    Ash, Garrett I; Kostek, Matthew A; Lee, Harold; Angelopoulos, Theodore J; Clarkson, Priscilla M; Gordon, Paul M; Moyna, Niall M; Visich, Paul S; Zoeller, Robert F; Price, Thomas B; Devaney, Joseph M; Gordish-Dressman, Heather; Thompson, Paul D; Hoffman, Eric P; Pescatello, Linda S

    2016-01-01

    Glucocorticoid receptor (NR3C1) polymorphisms associate with obesity, muscle strength, and cortisol sensitivity. We examined associations among four NR3C1 polymorphisms and the muscle response to resistance training (RT). European-American adults (n = 602, 23.8±0.4yr) completed a 12 week unilateral arm RT program. Maximum voluntary contraction (MVC) assessed isometric strength (kg) and MRI assessed biceps size (cm2) pre- and post-resistance training. Subjects were genotyped for NR3C1 -2722G>A, -1887G>A, -1017T>C, and +363A>G. Men carrying the -2722G allele gained less relative MVC (17.3±1.2vs33.5±6.1%) (p = 0.010) than AA homozygotes; men with -1887GG gained greater relative MVC than A allele carriers (19.6±1.4vs13.2±2.3%) (p = 0.016). Women carrying the -1017T allele gained greater relative size (18.7±0.5vs16.1±0.9%) (p = 0.016) than CC homozygotes. We found sex-specific NR3C1 associations with the muscle strength and size response to RT. Future studies should investigate whether these associations are partially explained by cortisol's actions in muscle tissue as they interact with sex differences in cortisol production. PMID:26821164

  1. Contribution of abdominal muscle strength to various activities of daily living of stroke patients with mild paralysis

    PubMed Central

    Fujita, Takaaki; Sato, Atsushi; Togashi, Yui; Kasahara, Ryuichi; Ohashi, Takuro; Yamamoto, Yuichi

    2015-01-01

    [Purpose] The trunk muscles frequently become weak after stroke, thus impacting overall activities of daily living. However, activities of daily living items closely related with trunk strength remain unclear. This study aimed to clarify the influence of trunk muscle weakness on activities of daily living items. [Subjects] The subjects were 24 stroke patients who fulfilled the following inclusion criteria: first stroke and the absence of severe paralysis, marked cognitive function deterioration, unilateral spatial neglect or apathy. [Methods] According to abdominal strength, the 24 patients were divided into a nonweakness group and a weakness group. For the assessment, we used the stroke impairment assessment set, the Berg balance scale, a simple test for evaluating hand function, grip strength, and functional independence measure scale scores and the results were compared between the groups. [Results] The Berg balance scale score and scores for dressing, toilet use, transfer to bed, and walk items of the functional independence measure were significantly lower in the weakness group than in the nonweakness group. [Conclusion] Our results suggest that weakness of the abdominal muscles adversely impacts the balance of patients with mild stroke as well as their ability to dress, use a toilet, transfer, and walk. Trunk training, including abdominal muscle exercises, can effectively improve the performance of these activities of daily living items. PMID:25931737

  2. Evaluation of perineal muscle strength in the first trimester of pregnancy 1

    PubMed Central

    Caroci, Adriana de Souza; Riesco, Maria Luiza Gonzalez; Rocha, Bianca Moraes Camargo; Ventura, Letícia de Jesus; Oliveira, Sheyla Guimarães

    2014-01-01

    OBJECTIVES: to analyze the Pelvic Floor Muscle Strength (PFMS) of pregnant women with one or more vaginal or cesarean deliveries; to compare the PFMS of these with pregnant women with the PFMS of primiparous women. METHODS: cross-sectional study with women up to 12 weeks pregnant, performed in Itapecerica da Serra, São Paulo state, from December 2012 to May 2013. The sample consisted of 110 pregnant women with one or more vaginal deliveries or cesarean sections and 110 primigravidae. The PFMS was evaluated by perineometry (Peritron(tm)) and vaginal digital palpation (modified Oxford scale). RESULTS: the average PFMS in pregnant women with a history of vaginal delivery or cesarean section was 33.4 (SD=21.2) cmH2O. From the Oxford scale, 75.4% of the pregnant women with previous vaginal or cesarean deliveries presented grade ≤ 2, and 5.5% grade ≥ 4; among the primiparae, 39.9% presented grade ≤ 2, and 50.9% grade ≥ 4, with a statistically significant difference (p<0.001). From the perineometry, there was no statistically significant difference between the PFMS and age, type of delivery, parity, body mass index, and genitourinary tract symptoms, however, there was a statistically significant difference between the pregnant women with and without a history of episiotomy (p=0.04). In the palpation, none of the variables showed a statistically significant difference. CONCLUSION: pregnancy and childbirth can reduce the PFMS. PMID:25591083

  3. Different Levels of Eccentric Resistance during Eight Weeks of Training Affect Muscle Strength and Lean Tissue Mass

    NASA Technical Reports Server (NTRS)

    English, K. L.; Loehr, J. A.; Lee, S. M. C.; Laughlin, M. S.; Hagan, R. D.

    2008-01-01

    Coupling concentric and eccentric muscle contractions appears to be important in the development of muscle strength and hypertrophy. The interim Resistive Exercise Device (iRED) currently used aboard the International Space Station does not seem to be as effective as free weight training in ambulatory subjects and has not completely protected against muscular deconditioning due to space flight. The lack of protection during space flight could be caused by iRED's proportionally lower eccentric resistance (60-70%) compared to concentric resistance. PURPOSE: To determine the effects of 8 wks of lower body resistive exercise training using five levels of eccentric resistance on muscle strength and lean tissue mass. METHODS: Forty untrained males (34.9 +/- 7 yrs, 80.9 +/- 9.8 kg, 178.2 +/- 7.1 cm; mean +/- SD) completed three 1-repetition maximum (1-RM) strength tests for both the supine leg press (LP) and supine heel raise (HR) prior to training; subjects were matched for LP strength and randomly assigned to one of five training groups. Concentric load (% 1-RM) was constant across groups during training, but each group trained with different levels of eccentric load (0%, 33%, 66%, 100%, or 138% of concentric). Subjects trained 3 d / wk for 8 wks using a periodized program for LP and HR based on percentages of the highest pre-training 1-RM. LP and HR 1-RM and leg lean mass (LLM; assessed by DEXA) were measured pre- and post-training. A two-way ANOVA was used to analyze all dependent measures. Tukey's post hoc tests were used to test significant main effects. Within group pre- to post-training changes were compared using paired t-tests with a Bonferroni adjustment. Statistical significance was set a priori at p 0.05. All data are expressed as mean +/- SE. RESULTS: LP 1-RM strength increased significantly in all groups pre- to post-training. The 138% group increase (20.1 +/- 3.7%) was significantly greater than the 0% (7.9 +/- 2.8%), 33% (7.7 +/- 4.6%), and 66% (7.5 +/- 4

  4. Lower values of handgrip strength and adductor pollicis muscle thickness are associated with hepatic encephalopathy manifestations in cirrhotic patients.

    PubMed

    Augusti, L; Franzoni, L C; Santos, L A A; Lima, T B; Ietsugu, M V; Koga, K H; Moriguchi, S M; Betting, L E; Caramori, C A; Silva, G F; Romeiro, F G

    2016-08-01

    Hepatic encephalopathy (HE) is a late complication of liver cirrhosis and is clearly associated with poor outcomes. Chronic liver insufficiency leads to progressive muscle wasting, impairing ammonia metabolism and thus increasing the risk for HE. Given the association between lean mass and adductor pollicis muscle thickness (APMT), it has been used to predict outcome and complications in many conditions, but not yet in cirrhotic patients. Therefore, this article aimed to study the association between HE manifestations and measures related to muscle mass and strength. This cross-sectional study included 54 cirrhotic outpatients with HE varying from subclinical to grade II according to the West-Haven criteria, who were submitted to neuropsychometric tests, electroencephalogram, brain Single Photon Emission Computed Tomography (SPECT), anthropometric measurements, handgrip strength (HGS) and dual energy X-ray absorptiometry exam (DXA). Multiple logistic regression analysis was performed to investigate the association between body composition measures and HE grade. Analysis of the area under the receiver operator characteristic (AUROC) curve revealed the values related to neurological manifestations (HE grades I and II). Reductions in APMT and HGS were associated with higher HE grades, suggesting a big impact caused by the loss of muscle mass and function on HE severity. The link between HE manifestations and anthropometric measures, namely APMT and HGS, point to a significant relation concerning skeletal muscles and the neurological impairment in this population. PMID:27131802

  5. Short-term low-intensity blood flow restricted interval training improves both aerobic fitness and muscle strength.

    PubMed

    de Oliveira, M F M; Caputo, F; Corvino, R B; Denadai, B S

    2016-09-01

    The present study aimed to analyze and compare the effects of four different interval-training protocols on aerobic fitness and muscle strength. Thirty-seven subjects (23.8 ± 4 years; 171.7 ± 9.5 cm; 70 ± 11 kg) were assigned to one of four groups: low-intensity interval training with (BFR, n = 10) or without (LOW, n = 7) blood flow restriction, high-intensity interval training (HIT, n = 10), and combined HIT and BFR (BFR + HIT, n = 10, every session performed 50% as BFR and 50% as HIT). Before and after 4 weeks training (3 days a week), the maximal oxygen uptake (VO2max ), maximal power output (Pmax ), onset blood lactate accumulation (OBLA), and muscle strength were measured for all subjects. All training groups were able to improve OBLA (BFR, 16%; HIT, 25%; HIT + BFR, 22%; LOW, 6%), with no difference between groups. However, VO2max and Pmax improved only for BFR (6%, 12%), HIT (9%, 15%) and HIT + BFR (6%, 11%), with no difference between groups. Muscle strength gains were only observed after BFR training (11%). This study demonstrates the advantage of short-term low-intensity interval BFR training as the single mode of training able to simultaneously improve aerobic fitness and muscular strength. PMID:26369387

  6. Effects of concurrent strength and endurance training on genes related to myostatin signaling pathway and muscle fiber responses.

    PubMed

    de Souza, Eduardo O; Tricoli, Valmor; Aoki, Marcelo S; Roschel, Hamilton; Brum, Patrícia C; Bacurau, Aline V N; Silva-Batista, Carla; Wilson, Jacob M; Neves, Manoel; Soares, Antonio G; Ugrinowitsch, Carlos

    2014-11-01

    Concurrent training (CT) seems to impair training-induced muscle hypertrophy. This study compared the effects of CT, strength training (ST) and interval training (IT) on the muscle fiber cross-sectional area (CSA) response, and on the expression of selected genes involved in the myostatin (MSTN) signaling mRNA levels. Thirty-seven physically active men were randomly divided into 4 groups: CT (n = 11), ST (n = 11), IT (n = 8), and control group (C) (n = 7) and underwent an 8-week training period. Vastus lateralis biopsy muscle samples were obtained at baseline and 48 hours after the last training session. Muscle fiber CSA, selected genes expression, and maximum dynamic ST (1 repetition maximum) were evaluated before and after training. Type IIa and type I muscle fiber CSA increased from pre- to posttest only in the ST group (17.08 and 17.9%, respectively). The SMAD-7 gene expression significantly increased at the posttest in the ST (53.9%) and CT groups (39.3%). The MSTN and its regulatory genes ActIIb, FLST-3, FOXO-3a, and GASP-1 mRNA levels remained unchanged across time and groups. One repetition maximum increased from pre- to posttest in both the ST and CT groups (ST = 18.5%; CT = 17.6%). Our findings are suggestive that MSTN and their regulatory genes at transcript level cannot differentiate muscle fiber CSA responses between CT and ST regimens in humans. PMID:24832980

  7. The effect of a combined strength and proprioceptive training on muscle strength and postural balance in boys with intellectual disability: An exploratory study.

    PubMed

    Kachouri, Hiba; Borji, Rihab; Baccouch, Rym; Laatar, Rabeb; Rebai, Haithem; Sahli, Sonia

    2016-01-01

    The aim of our study was to investigate the effect of a combined strength and proprioception training (CSPT) program on muscle strength and postural balance in children with intellectual disability (ID). The maximum voluntary contraction (MVC) and postural parameters (CoPVm, CoPLX, CoPLY) of 20 children with ID were recorded before and after 8 weeks of a CSPT program. The participants were divided into two groups: an experimental group who attended a CSPT program and a control group who continued with daily activities. In the trained group, the MVC increased significantly (p<0.001) after the training period and the postural parameters decreased significantly in Double-Leg Stance (DLS) and One-Leg Stance (OLS) during the firm surface condition as well as in the DLS during the foam surface condition; in both eyes open (EO) and eyes closed (EC) conditions. A CSPT program improves postural balance in children with ID could be due to the enhancement in muscle strength and proprioceptive input integration. PMID:26994823

  8. The Effect of a 12-Week Omega-3 Supplementation on Body Composition, Muscle Strength and Physical Performance in Elderly Individuals with Decreased Muscle Mass.

    PubMed

    Krzymińska-Siemaszko, Roma; Czepulis, Natasza; Lewandowicz, Marta; Zasadzka, Ewa; Suwalska, Aleksandra; Witowski, Janusz; Wieczorowska-Tobis, Katarzyna

    2015-09-01

    The aim of the study was to assess the effect of a polyunsaturated omega-3 fatty acids (PUFA) supplementation on the parameters of body composition, muscle strength and physical performance in elderly people with decreased muscle mass (DMM). Fifty three elderly people with an ALM index (the ratio of appendicular lean mass to squared height) either below (-2SD: low muscle mass-LMM) or between (-1SD and -2SD: the risk of LMM-rLMM) the ALM index for the young Polish reference population were randomly assigned to PUFA-treated groups (LMM-PUFA, rLMM-PUFA) or control groups (LMM-control, rLMM-control). PUFA-treated groups received capsules containing 1.3 g of PUFA and 10 mg of vitamin E, while the control groups received 11 mg of vitamin E daily for 12 weeks. Body composition (BIA analysis), muscle strength (hand grip measured with dynamometer) and physical performance (Timed Up and Go test-TUG) were assessed before and after supplementation. No statistically significant differences were observed either in muscle mass or in the hand grip and TUG in any group. The post-pre difference (mean ± SD) in ALM index was as follows (kg/m²): LMM-PUFA: 0.00 ± 0.30, rLMM-PUFA: 0.00 ± 0.22, LMM-control: 0.03 ± 0.36, rLMM-control: -0.03 ± 0.20. In our study, a 12 week supplementation of PUFA did not affect the evaluated parameters in elderly individuals with DMM. PMID:26343698

  9. Serotonin and Histamine Therapy Increases Tetanic Forces of Myoblasts, Reduces Muscle Injury, and Improves Grip Strength Performance of Dmdmdx Mice

    PubMed Central

    Lins, Jeremy; Lambert, Kristyn; Lazauski, Joan; Spaulding, James; McMichael, John

    2015-01-01

    Duchenne muscular dystrophy (DMD) is a recessive X-linked fatal disorder caused by a mutation in the dystrophin gene. Although several therapeutic approaches have been studied, none has led to substantial long-term effects in patients. The aim of this study was to test a serotonin and histamine (S&H) combination on human skeletal myoblasts and Dmdmdx mice for its effects on muscle strength and injury. Normal human bioartificial muscles (BAMs) were treated, and muscle tetanic forces and muscle injury tests were performed using the MyoForce Analysis System. Dmdmdx mice, the murine model of DMD, were administered serotonin, histamine, or S&H combination twice daily for 6 weeks, and functional performance tests were conducted once a week. The S&H combination treatment caused significant increases in tetanic forces at all time points and concentrations tested as compared to the saline controls. Dose response of the BAMs to the treatment demonstrated a significant increase in force generation at all concentrations compared to the controls after 3 to 4 days of drug treatment. The highest 3 concentrations had a significant effect on lowering contractile-induced injury as measured by a reduction in the release of adenylate kinase. Histamine-only and S&H treatments improved grip strength of Dmdmdx mice, whereas serotonin-only treatment resulted in no significant improvement in muscle strength. The results of this study indicate that S&H therapy might be a promising new strategy for muscular dystrophies and that the mechanism should be further investigated. PMID:26740813

  10. Insulin signaling in skeletal muscle of HIV-infected patients in response to endurance and strength training

    PubMed Central

    Broholm, Christa; Mathur, Neha; Hvid, Thine; Grøndahl, Thomas Sahl; Frøsig, Christian; Pedersen, Bente Klarlund; Lindegaard, Birgitte

    2013-01-01

    Human immunodeficiency virus (HIV)-infected patients with lipodystrophy have decreased insulin-stimulated glucose uptake. Both endurance and resistance training improve insulin-stimulated glucose uptake in skeletal muscle of HIV-infected patients, but the mechanisms are unknown. This study aims to identify the molecular pathways involved in the beneficial effects of training on insulin-stimulated glucose uptake in skeletal muscle of HIV-infected patients. Eighteen sedentary male HIV-infected patients underwent a 16 week supervised training intervention, either resistance or strength training. Euglycemic–hyperinsulinemic clamps with muscle biopsies were performed before and after the training interventions. Fifteen age- and body mass index (BMI)-matched HIV-negative men served as a sedentary baseline group. Phosphorylation and total protein expression of insulin signaling molecules as well as glycogen synthase (GS) activity were analyzed in skeletal muscle biopsies in relation to insulin stimulation before and after training. HIV-infected patients had reduced basal and insulin-stimulated GS activity (%fractional velocity, [FV]) as well as impaired insulin-stimulated Aktthr308 phosphorylation. Despite improving insulin-stimulated glucose uptake, neither endurance nor strength training changed the phosphorylation status of insulin signaling proteins or affected GS activity. However; endurance training markedly increased the total Akt protein expression, and both training modalities increased hexokinase II (HKII) protein. HIV-infected patients with lipodystrophy have decreased insulin-stimulated glucose uptake in skeletal muscle and defects in insulin-stimulated phosphorylation of Aktthr308. Endurance and strength training increase insulin-stimulated glucose uptake in these patients, and the muscular training adaptation is associated with improved capacity for phosphorylation of glucose by HKII, rather than changes in markers of insulin signaling to glucose uptake or

  11. Quantitative muscle strength assessment in duchenne muscular dystrophy: longitudinal study and correlation with functional measures

    PubMed Central

    2012-01-01

    Background The aim of this study was to perform a longitudinal assessment using Quantitative Muscle Testing (QMT) in a cohort of ambulant boys affected by Duchenne muscular dystrophy (DMD) and to correlate the results of QMT with functional measures. This study is to date the most thorough long-term evaluation of QMT in a cohort of DMD patients correlated with other measures, such as the North Star Ambulatory Assessment (NSAA) or thee 6-min walk test (6MWT). Methods This is a single centre, prospective, non-randomised, study assessing QMT using the Kin Com® 125 machine in a study cohort of 28 ambulant DMD boys, aged 5 to 12 years. This cohort was assessed longitudinally over a 12 months period of time with 3 monthly assessments for QMT and with assessment of functional abilities, using the NSAA and the 6MWT at baseline and at 12 months only. QMT was also used in a control group of 13 healthy age-matched boys examined at baseline and at 12 months. Results There was an increase in QMT over 12 months in boys below the age of 7.5 years while in boys above the age of 7.5 years, QMT showed a significant decrease. All the average one-year changes were significantly different than those experienced by healthy controls. We also found a good correlation between quantitative tests and the other measures that was more obvious in the stronger children. Conclusion Our longitudinal data using QMT in a cohort of DMD patients suggest that this could be used as an additional tool to monitor changes, providing additional information on segmental strength. PMID:22974002

  12. The individual and combined influence of ACE and ACTN3 genotypes on muscle phenotypes before and after strength training.

    PubMed

    Erskine, R M; Williams, A G; Jones, D A; Stewart, C E; Degens, H

    2014-08-01

    Alternative measures of muscle size, strength, and power to those used in previous studies could help resolve the controversy surrounding associations between polymorphisms of the angiotensin-I converting enzyme (ACE) and α-actinin-3 (ACTN3) genes and skeletal muscle phenotypes, and the responses to resistance training (RT). To this end, we measured quadriceps femoris muscle volume (Vm), physiological cross-sectional area (PCSA), maximum isometric force (Ft), specific force (Ft per unit PCSA), maximum isoinertial strength (1-RM), and maximum power (Wmax ; n = 40) before and after 9-week knee extension RT in 51 previously untrained young men, who were genotyped for the ACE I/D and ACTN3 R577X polymorphisms. ACTN3 R-allele carriers had greater Vm, 1-RM, and Wmax than XX homozygotes at baseline (all P < 0.05), but responses to RT were independent of ACTN3 genotype (all P > 0.05). Muscle phenotypes were independent of ACE genotype before (all P > 0.05) and after RT (all P > 0.01). However, people with the "optimal" ACE+ACTN3 genotype combination had greater baseline 1-RM and Wmax compared to those with the "suboptimal" profile (both P < 0.0125). We show for the first time that the ACTN3 R577X polymorphism is associated with human Vm and (independently and in combination with the ACE I/D polymorphism) influences 1-RM and Wmax. PMID:23384112

  13. Yacht type and crew-specific differences in anthropometric, aerobic capacity, and muscle strength parameters among international Olympic class sailors.

    PubMed

    Bojsen-Møller, Jens; Larsson, Benny; Magnusson, S Peter; Aagaard, Per

    2007-08-01

    Physical fitness and muscular strength are important performance factors for Olympic class sailors, but the physical demands vary greatly between yacht classes, and limited information is available regarding the physical demands for the different crew positions. In the present paper, strength and aerobic capacity data from elite Olympic sailors are presented and compared with previous findings. Furthermore, a system for classification of Olympic class sailors is suggested. Peak aerobic capacity (peak oxygen uptake, VO(2peak)) and maximal isometric and isokinetic muscle strength of the knee extensors and flexors were assessed, together with the hamstring/quadriceps strength ratio (H/Q ratio). Peak aerobic capacity (ml O(2) . min(-1) . kg(-2/3)) was as follows: males - static hikers (n = 5) 215, s = 7; dynamic hikers (n = 8) 252, s = 17; trapezing helmsmen (n = 6) 234, s = 15; trapezing crew (n = 10) 239, s = 16; females - dynamic hikers (n = 6) 194, s = 16; trapezing crew (n = 2) 200, s = 13. Strength data for hikers, presented as peak moments (normalized to body weight) obtained during eccentric, isometric, and concentric contraction (Nm . kg(-1)) respectively were as follows: males - quadriceps: 3.66 (s = 0.68), 3.97 (s = 0.66), 1.82 (s = 0.34); hamstrings: 1.93 (s = 0.22), 1.38 (s = 0.41), 1.05 (s = 0.21); females - quadriceps: 3.84 (s = 0.71), 3.81 (s = 0.58), 1.60 (s = 0.28); hamstrings: 1.75 (s = 0.23), 1.10 (s = 0.16), 0.84 (s = 0.13). The peak moment based H/Q ratios for slow eccentric and concentric contractions were 0.42 (s = 0.11) and 0.39 (s = 0.04) for males and 0.43 (s = 0.06) and 0.39 (s = 0.04) for females respectively. Elite Olympic class sailors demonstrated high VO(2peak) values comparable to those observed in other non-endurance sports. The strength data revealed very high quadriceps strength for hikers, which is likely a result of the high muscle forces encountered during sailing, and a low H/Q ratio. To ensure optimal knee joint stabilization

  14. Feasibility of resistance training in adult McArdle patients: clinical outcomes and muscle strength and mass benefits

    PubMed Central

    Santalla, Alfredo; Munguía-Izquierdo, Diego; Brea-Alejo, Lidia; Pagola-Aldazábal, Itziar; Díez-Bermejo, Jorge; Fleck, Steven J.; Ara, Ignacio; Lucia, Alejandro

    2014-01-01

    We analyzed the effects of a 4-month resistance (weight lifting) training program followed by a 2-month detraining period in 7 adult McArdle patients (5 female) on: muscle mass (assessed by DXA), strength, serum creatine kinase (CK) activity and clinical severity. Adherence to training was ≥84% in all patients and no major contraindication or side effect was noted during the training or strength assessment sessions. The training program had a significant impact on total and lower extremities’ lean mass (P < 0.05 for the time effect), with mean values increasing with training by +855 g (95% confidence interval (CI): 30, 1679) and +547 g (95%CI: 116, 978), respectively, and significantly decreasing with detraining. Body fat showed no significant changes over the study period. Bench press and half-squat performance, expressed as the highest value of average muscle power (W) or force (N) in the concentric-repetition phase of both tests showed a consistent increase over the 4-month training period, and decreased with detraining. Yet muscle strength and power detraining values were significantly higher than pre-training values, indicating that a training effect was still present after detraining. Importantly, all the participants, with no exception, showed a clear gain in muscle strength after the 4-month training period, e.g., bench press: +52 W (95% CI: 13, 91); half-squat: +173 W (95% CI: 96, 251). No significant time effect (P > 0.05) was noted for baseline or post strength assessment values of serum CK activity, which remained essentially within the range reported in our laboratory for McArdle patients. All the patients changed to a lower severity class with training, such that none of them were in the highest disease severity class (3) after the intervention and, as such, they did not have fixed muscle weakness after training. Clinical improvements were retained, in all but one patient, after detraining, such that after detraining all patients were classed as

  15. Deer Antler Extract Improves Fatigue Effect through Altering the Expression of Genes Related to Muscle Strength in Skeletal Muscle of Mice

    PubMed Central

    Hsiang, Chien-Yun; Lin, Yung-Chang; Ho, Tin-Yun

    2014-01-01

    Deer antler is a well-known traditional Chinese medicine used in Asian countries for the tonic and the improvement of aging symptoms. The present study was designed to investigate the antifatigue effect and mechanism of Formosan sambar deer tip antler extract (FSDTAE). The swimming times to exhaustion of mice administered FSDTAE (8.2 mg/day) for 28 days were apparently longer than those of the vehicle-treated mice in forced swim test. However, the indicators of fatigue, such as the reduction in glucose level and the increases in blood urea nitrogen and lactic acid levels, were not significantly inhibited by FSDTAE. Therefore, microarray analysis was further used to examine the anti-fatigue mechanism of FSDTAE. We selected genes with fold changes >2 or <−2 in skeletal muscle for pathway analysis. FSDTAE-affected genes were involved in 9 different signaling pathways, such as GnRH signaling pathway and insulin signaling pathway. All of the significantly expressed genes were classified into 8 different categories by their functions. The most enriched category was muscular system, and 6 upregulated genes, such as troponin I, troponin T1, cysteine and glycine-rich protein 2, myosin heavy polypeptide 7, tropomyosin 2, and myomesin family member 3, were responsible for the development and contraction of muscle. Real-time PCR analysis indicated that FSDTAE increased troponins mRNA expression in skeletal muscle. In conclusion, our findings suggested that FSDTAE might increase the muscle strength through the upregulation of genes responsible for muscle contraction and consequently exhibited the anti-fatigue effect in mice. PMID:24701242

  16. Functional Capacity, Respiratory Muscle Strength, and Oxygen Consumption Predict Mortality in Patients with Cirrhosis

    PubMed Central

    Telles da Rosa, Luis Henrique; Garcia, Eduardo; Marroni, Cláudio Augusto

    2016-01-01

    Introduction. Liver diseases influence musculoskeletal functions and may negatively affect the exercise capacity of patients with cirrhosis. Aim. To test the relationship between the six-minute walk test (6MWT), maximal inspiratory pressure (MIP), and exercise capacity (VO2peak) measures and the survival rate of patients with cirrhosis. Methods. This prospective cohort study consisted of 86 patients diagnosed with cirrhosis with the following aetiology: hepatitis C virus (HCV), hepatitis B virus (HBV), and/or alcoholic cirrhosis (AC). All patients were followed up for three years and submitted to the 6MWT, pressure measurements with a compound gauge, and an exercise test (VO2peak). Results. The survival analysis showed that the individuals who covered a distance shorter than 410 m during the 6MWT had a survival rate of 55% compared with a rate of 97% for the individuals who walked more than 410 m (p = 0.0001). Individuals with MIPs below −70 cmH2O had a survival rate of 62% compared with a rate of 93% for those with MIPs above −70 cmH2O (p = 0.0001). The patients with values below 17 mL/kg had a survival rate of 55% compared with a rate of 94% for those with values above 17 mL/kg (p = 0.0001). Conclusion. The 6MWT distance, MIP, and oxygen consumption are predictors of mortality in patients with cirrhosis. PMID:27559536

  17. Functional Capacity, Respiratory Muscle Strength, and Oxygen Consumption Predict Mortality in Patients with Cirrhosis.

    PubMed

    Faustini Pereira, José Leonardo; Galant, Lucas Homercher; Rossi, Danusa; Telles da Rosa, Luis Henrique; Garcia, Eduardo; de Mello Brandão, Ajácio Bandeira; Marroni, Cláudio Augusto

    2016-01-01

    Introduction. Liver diseases influence musculoskeletal functions and may negatively affect the exercise capacity of patients with cirrhosis. Aim. To test the relationship between the six-minute walk test (6MWT), maximal inspiratory pressure (MIP), and exercise capacity (VO2peak) measures and the survival rate of patients with cirrhosis. Methods. This prospective cohort study consisted of 86 patients diagnosed with cirrhosis with the following aetiology: hepatitis C virus (HCV), hepatitis B virus (HBV), and/or alcoholic cirrhosis (AC). All patients were followed up for three years and submitted to the 6MWT, pressure measurements with a compound gauge, and an exercise test (VO2peak). Results. The survival analysis showed that the individuals who covered a distance shorter than 410 m during the 6MWT had a survival rate of 55% compared with a rate of 97% for the individuals who walked more than 410 m (p = 0.0001). Individuals with MIPs below -70 cmH2O had a survival rate of 62% compared with a rate of 93% for those with MIPs above -70 cmH2O (p = 0.0001). The patients with values below 17 mL/kg had a survival rate of 55% compared with a rate of 94% for those with values above 17 mL/kg (p = 0.0001). Conclusion. The 6MWT distance, MIP, and oxygen consumption are predictors of mortality in patients with cirrhosis. PMID:27559536

  18. Motor Imagery Training on Muscle Strength and Gait Performance in Ambulant Stroke Subjects-A Randomized Clinical Trial

    PubMed Central

    Chakrapani, M.; Kedambadi, Rakshith

    2016-01-01

    Introduction The ultimate goal of physiotherapy in stroke rehabilitation is focused towards physical independence and to restore their functional ability during activities of daily living (ADLs). Motor imagery (MI) is an active process during which a specific action is reproduced within working memory without any actual movements. MI training enhances motor learning, neural reorganization and cortical activation in stroke. The efficacy of MI training involving lower extremity mobility tasks need to be assessed. Aim To evaluate the effects of combining motor imagery with physical practice in paretic Lower Extremity Muscles Strength and Gait Performance in Ambulant Stroke subjects. Materials and Methods A Randomized Clinical Trial was conducted in Department of Physical Therapy, Tertiary Care Hospitals, Mangalore, India which includes 40 hemi paretic subjects (>3 months post-stroke) who were ambulant with good imagery ability in both KVIQ-20 ≥ 60 and Time dependent MI screening test were recruited and randomly allocated into task-oriented training group (n=20) and task-oriented training group plus MI group (n=20). Subjects in both groups underwent task orientated training for lower extremity 45-60 minutes, 4 days per week for 3 weeks. In addition, the experimental group received 30 minutes of audio-based lower extremity mobility tasks for MI practice. Isometric muscle strength of Hip, Knee and Ankle using a hand-held dynamometer and self-selected 10 m gait speed were assessed before and after 3 weeks of intervention. Results Both the groups had found a significant change for all the outcome measures following 3 weeks of interventions with p <.05. The experimental group had shown a significant improvement in paretic hip muscles (both flexors and extensors), knee extensors and ankle dorsiflexors and gait speed compare to control group with p < .05 between group analyses. Conclusion Additional task specific MI training improves paretic muscle strength and gait

  19. Multicomponent training program with weight-bearing exercises elicits favorable bone density, muscle strength, and balance adaptations in older women.

    PubMed

    Marques, Elisa A; Mota, Jorge; Machado, Leandro; Sousa, Filipa; Coelho, Margarida; Moreira, Pedro; Carvalho, Joana

    2011-02-01

    Physical exercise is advised as a preventive and therapeutic strategy against aging-induced bone weakness. In this study we examined the effects of 8-month multicomponent training with weight-bearing exercises on different risk factors of falling, including muscle strength, balance, agility, and bone mineral density (BMD) in older women. Participants were randomly assigned to either an exercise-training group (ET, n = 30) or a control group (CON, n = 30). Twenty-seven subjects in the ET group and 22 in the CON group completed the study. Training was performed twice a week and was designed to load bones with intermittent and multidirectional compressive forces and to improve physical function. Outcome measures included lumbar spine and proximal femoral BMD (by dual X-ray absorptiometry), muscle strength, balance, handgrip strength, walking performance, fat mass, and anthropometric data. Potential confounding variables included dietary intake, accelerometer-based physical activity, and molecularly defined lactase nonpersistence. After 8 months, the ET group decreased percent fat mass and improved handgrip strength, postural sway, strength on knee flexion at 180°/s, and BMD at the femoral neck (+2.8%). Both groups decreased waist circumference and improved dynamic balance, chair stand performance, strength on knee extension for the right leg at 180°/s, and knee flexion for both legs at 60°/s. No associations were found between lactase nonpersistence and BMD changes. Data suggest that 8 months of moderate-impact weight-bearing and multicomponent exercises reduces the potential risk factors for falls and related fractures in older women. PMID:21113584

  20. Effects of strength, endurance and combined training on muscle strength, walking speed and dynamic balance in aging men.

    PubMed

    Holviala, J; Kraemer, W J; Sillanpää, E; Karppinen, H; Avela, J; Kauhanen, A; Häkkinen, A; Häkkinen, K

    2012-04-01

    The aim of this study was to examine effects of 21-week twice weekly strength (ST), endurance (ET) and combined (ST + ET 2 + 2 times a week) (SET) training on neuromuscular, endurance and walking performances as well as balance. 108 healthy men (56.3 ± 9.9 years) were divided into three training (ST; n = 30, ET; n = 26, SET; n = 31) groups and controls (C n = 21). Dynamic 1RM and explosive leg presses (1RMleg, 50%1RMleg), peak oxygen uptake using a bicycle ergometer (VO(2peak)), 10 m loaded walking time (10WALK) and dynamic balance distance (DYND) were measured. Significant increases were observed in maximal 1RMleg of 21% in ST (p < 0.001) and 22% in SET (p < 0.001) and in explosive 50%1RMleg of 7.5% in ST (p = 0.005) and 10.2% in SET (p < 0.001). VO(2peak) increased by 12.5% in ET (p = 0.001) and 9.8% in SET (p < 0.001). Significant decreases occurred in 10WALK in ST (p < 0.001) and SET (p = 0.003) and also in DYND of -10.3% in ST (p = 0.002) and -8% in SET (p = 0.028). The changes in C remained minor in all variables. In conclusion, ST and SET training produced significant improvements in maximal and explosive strength, walking speed and balance without any interference effect in SET. Significant but moderate relationships were observed between strength and dynamic balance and walking speed, while no corresponding correlations were found in the ET group. PMID:21796409

  1. L-carnitine as an ergogenic aid for patients with chronic obstructive pulmonary disease submitted to whole-body and respiratory muscle training programs.

    PubMed

    Borghi-Silva, A; Baldissera, V; Sampaio, L M M; Pires-DiLorenzo, V A; Jamami, M; Demonte, A; Marchini, J S; Costa, D

    2006-04-01

    The effects of adding L-carnitine to a whole-body and respiratory training program were determined in moderate-to-severe chronic obstructive pulmonary disease (COPD) patients. Sixteen COPD patients (66 +/- 7 years) were randomly assigned to L-carnitine (CG) or placebo group (PG) that received either L-carnitine or saline solution (2 g/day, orally) for 6 weeks (forced expiratory volume on first second was 38 +/- 16 and 36 +/- 12%, respectively). Both groups participated in three weekly 30-min treadmill and threshold inspiratory muscle training sessions, with 3 sets of 10 loaded inspirations (40%) at maximal inspiratory pressure. Nutritional status, exercise tolerance on a treadmill and six-minute walking test, blood lactate, heart rate, blood pressure, and respiratory muscle strength were determined as baseline and on day 42. Maximal capacity in the incremental exercise test was significantly improved in both groups (P < 0.05). Blood lactate, blood pressure, oxygen saturation, and heart rate at identical exercise levels were lower in CG after training (P < 0.05). Inspiratory muscle strength and walking test tolerance were significantly improved in both groups, but the gains of CG were significantly higher than those of PG (40 +/- 14 vs 14 +/- 5 cmH2O, and 87 +/- 30 vs 34 +/- 29 m, respectively; P < 0.05). Blood lactate concentration was significantly lower in CG than in PG (1.6 +/- 0.7 vs 2.3 +/- 0.7 mM, P < 0.05). The present data suggest that carnitine can improve exercise tolerance and inspiratory muscle strength in COPD patients, as well as reduce lactate production. PMID:16612469

  2. Comparison Between Strength of Muscles Rotating the Knee in Healthy Individuals and Patients one Year after an ACL Reconstruction

    PubMed Central

    Popieluch, Marcın; Śmigıelski, Robert; Straszewski, Darıusz; Plenzler, Marcın; Stanıszewski, Mıchał

    2014-01-01

    Objectives: In this study we have made an attempt to establish torque value of the muscles rotating the knee of patients who had ruptured their ACLs during an amateur football practise on an artificial turf. In this study we presented biomechanical research on torques of muscles responsible for internal and external rotation of the lower leg. We presented a method whereby it is possible to measure the muscle strength before and after the ACL rupture but also during the process of rehabilitation and after its finish. The available literature on measurements of torque of the knee is quite extensive though it mainly describes torques of muscles flexing and extending the joint. In Polish literature there is scarcity of studies focused on torques of muscles rotating the knee. In foreign literature there is an increasing emphasis on the role of lower leg rotation, as the element greatly impacting, for instance, the position of the foot. Methods: The study presents results of 22 patients and 50 healthy individuals (not practising any particular sport regularly) being the control group. All patients had their ACLs reconstructed using the double-bundle technique. The material for the graft was obtained from the hamstrings. The aim was to measure the maximal torque of the muscles responsible for external and internal rotation of the knee (lower leg in a static state using a special device). The device allowed measurement of the torque of muscles rotating the lower leg in its axis by stabilizing the ankle with special emphasis on foot mounting (stabilization of footwear). The special device was connected to a PC with CPS/HMF software. The software enabled observation and recording of increase in the value of the torque until it reached its maximum. The measurements were taken in two knee positions: 30 degrees and 90 degrees flexion. Results: The result were analyzed statistically, means and SDs were calculated. Only right-legged subjects were included in the analysis. The

  3. Effect of Dietary Patterns on Muscle Strength and Physical Performance in the Very Old: Findings from the Newcastle 85+ Study

    PubMed Central

    Granic, Antoneta; Jagger, Carol; Davies, Karen; Adamson, Ashley; Kirkwood, Thomas; Hill, Tom R.; Siervo, Mario; Mathers, John C.; Sayer, Avan Aihie

    2016-01-01

    Background Healthy diet has been associated with better muscle strength and physical performance in cross-sectional studies of older adults but the effect of dietary patterns (DP) on subsequent decline, particularly in the very old (aged 85+), has not been determined. Objective We investigated the association between previously established DP and decline in muscle strength and physical performance in the very old. Design 791 participants (61.8% women) from the Newcastle 85+ Study were followed-up for change in hand grip strength (HGS) and Timed Up-and Go (TUG) test over 5 years (four waves 1.5 years apart). Mixed models were used to determine the effects of DP on muscle strength and physical performance in the entire cohort and separately by sex. Results Previously we have established three DP that varied in intake of red meats, potato, gravy and butter and differed with key health and social factors. HGS declined linearly by 1.59 kgF in men and 1.08 kgF in women (both p<0.001), and TUG slowed by 0.13 log10-transformed seconds (log10-s) in men and 0.11 log10-s in women per wave after adjusting for important covariates (both p<0.001), and also showed a nonlinear change (p<0.001). Men in DP1 (‘High Red Meat’) had worse overall HGS (β = -1.70, p = 0.05), but men in DP3 (‘High Butter’) had a steeper decline (β = -0.63, p = 0.05) than men in DP2 (‘Low Meat’). Men in DP1 and women in DP3 also had overall slower TUG than those in DP2 (β = 0.08, p = 0.001 and β = 0.06, p = 0.01, respectively), but similar rate of decline after adjusting for sociodemographic, lifestyle, health, and functioning factors. The results for HGS and TUG were not affected by participants’ cognitive status. Conclusions DP high in red meats, potato and gravy (DP1), or butter (DP3) may adversely affect muscle strength and physical performance in later life, independently of important covariates and cognitive status. PMID:26934360

  4. Inspiratory flow and intrapulmonary gas distribution

    SciTech Connect

    Rehder, K.; Knopp, T.J.; Brusasco, V.; Didier, E.P.

    1981-01-01

    The effect of flow of inspired gas on intrapulmonary gas distribution was examined by analysis of regional pulmonary /sup 133/Xe clearances and of total pulmonary /sup 133/Xe clearance measured at the mouth after equilibration of the lungs with /sup 133/Xe. Five awake healthy volunteers (24 to 40 yr of age) and another 5 healthy, anesthetized-paralyzed volunteers (26 to 28 yr of age) were studied while they were in the right lateral decubitus position. The awake subjects were studied at 3 inspiratory flows (0.4, 0.7, and 1.0 L/s) and the anesthetized-paralyzed subjects at 4 inspiratory flows (0.2, 0.5, 1.1, and 1.6 L/s). Interregional differences in /sup 133/Xe clearances along the vertical axis were significantly less during anesthesia-paralysis and mechanical ventilation than during spontaneous breathing in the awake state. No differences in the regional or total pulmonary /sup 133/Xe clearances were detected at these different flows in either of the two states, i.e., the difference between the awake and anesthetized-paralyzed states persisted.

  5. Mobility and Muscle Strength Together are More Strongly Correlated with Falls in Suburb-Dwelling Older Chinese

    PubMed Central

    Wang, Xiuyang; Ma, Yixuan; Wang, Jiazhong; Han, Peipei; Dong, Renwei; Kang, Li; Zhang, Wen; Shen, Suxing; Wang, Jing; Li, Dongfang; Zhou, Maoran; Wang, Liancheng; Niu, Kaijun; Guo, Qi

    2016-01-01

    Falls are common in older adults and result in adverse outcomes. Impaired mobility and poor muscle strength have been consistently identified as the main contributors to falls. We choose three easy-to-perform tests (i.e. Timed Up and Go test (TUGT), walking speed (WS) and grip strength (GS)) in order to assess mobility and muscle strength to further define their relationship with falls. This study is cross-sectional, consisting of 1092 residents over 60-year-old; 589 were female. 204 (18.68%) participants reported falling at least once in the past year. It was found that, of the three tests evaluated independently, a TUGT < 9.1750 s had the strongest association with fewer falls. When evaluating these tests as pairs, the combination of a TUGT < 9.1750 s and a WS < 0.9963 m/s was the best protective indicator of falls after adjusting for age, sex and other variables. When evaluating all three tests in conjunction with each other, the combination of a TUGT < 9.1750 s, a WS < 0.9963 m/s, and a GS > 0.3816 was most correlated with less possibility of falls. The combination of a better TUGT performance, a stronger GS, and a slower WS is the most strongly correlated with less possibility of falls. PMID:27146721

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

    PubMed Central

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

    2015-01-01

    Objective To investigate the associations of exercise capacity and muscle strength in late adolescence with risk of vascular disease and arrhythmia. Design Cohort study. Setting General population in Sweden. Participants 1.1 million men who participated in mandatory military conscription between 1 August 1972 and 31 December 1995, at a median age of 18.2 years. Participants were followed until 31 December 2010. Main outcomes Associations between exercise capacity and muscle strength with risk of vascular disease and subgroups (ischaemic heart disease, heart failure, stroke, and cardiovascular death) and risk of arrhythmia and subgroups (atrial fibrillation or flutter, bradyarrhythmia, supraventricular tachycardia, and ventricular arrhythmia or sudden cardiac death). Maximum exercise capacity was estimated by the ergometer bicycle test, and muscle strength was measured as handgrip strength by a hand dynamometer. High exercise capacity or muscle strength was deemed as above the median level. Results During a median follow-up of 26.3 years, 26 088 vascular disease events and 17 312 arrhythmia events were recorded. Exercise capacity was inversely associated with risk of vascular disease and its subgroups. Muscle strength was also inversely associated with vascular disease risk, driven by associations of higher muscle strength with lower risk of heart failure and cardiovascular death. Exercise capacity had a U shaped association with risk of arrhythmia, driven by a direct association with risk of atrial fibrillation and a U shaped association with bradyarrhythmia. Higher muscle strength was associated with lower risk of arrhythmia (specifically, lower risk of bradyarrhythmia and ventricular arrhythmia). The combination of high exercise capacity and high muscle strength was associated with a hazard ratio of 0.67 (95% confidence interval 0.65 to 0.70) for vascular events and 0.92 (0.88 to 0.97) for arrhythmia compared with the combination of low exercise capacity and

  7. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Inspiratory airway pressure meter. 868.1780 Section 868.1780 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  8. Analysis of three different equations for predicting quadriceps femoris muscle strength in patients with COPD *

    PubMed Central

    Nellessen, Aline Gonçalves; Donária, Leila; Hernandes, Nidia Aparecida; Pitta, Fabio

    2015-01-01

    Abstract Objective: To compare equations for predicting peak quadriceps femoris (QF) muscle force; to determine the agreement among the equations in identifying QF muscle weakness in COPD patients; and to assess the differences in characteristics among the groups of patients classified as having or not having QF muscle weakness by each equation. Methods: Fifty-six COPD patients underwent assessment of peak QF muscle force by dynamometry (maximal voluntary isometric contraction of knee extension). Predicted values were calculated with three equations: an age-height-weight-gender equation (Eq-AHWG); an age-weight-gender equation (Eq-AWG); and an age-fat-free mass-gender equation (Eq-AFFMG). Results: Comparison of the percentage of predicted values obtained with the three equations showed that the Eq-AHWG gave higher values than did the Eq-AWG and Eq-AFFMG, with no difference between the last two. The Eq-AHWG showed moderate agreement with the Eq-AWG and Eq-AFFMG, whereas the last two also showed moderate, albeit lower, agreement with each other. In the sample as a whole, QF muscle weakness (< 80% of predicted) was identified by the Eq-AHWG, Eq-AWG, and Eq-AFFMG in 59%, 68%, and 70% of the patients, respectively (p > 0.05). Age, fat-free mass, and body mass index are characteristics that differentiate between patients with and without QF muscle weakness. Conclusions: The three equations were statistically equivalent in classifying COPD patients as having or not having QF muscle weakness. However, the Eq-AHWG gave higher peak force values than did the Eq-AWG and the Eq-AFFMG, as well as showing greater agreement with the other equations. PMID:26398750

  9. Effect of physiotherapy on the strength of tibial internal rotator muscles in males after anterior cruciate ligament reconstruction (ACLR)

    PubMed Central

    Czamara, Andrzej; Szuba, Łukasz; Krzemińska, Aleksandra; Tomaszewski, Wiesław; Wilk-Frańczuk, Magdalena

    2011-01-01

    Summary Background The goal of this study was to evaluate the effect of physiotherapy on the strength of muscles responsible for tibial internal rotation (IR) in male patients after anterior cruciate ligament reconstruction (ACLR) using autografts of the semitendinosus and gracilis muscles (STGR). Material/Methods Fifty-nine males were examined. The first group consisted of 19 patients subjected to 4-stage physiotherapy following ACLR. The second group consisted of 20 males without knee injuries. The third group consisted of 20 males who had not undergone systematic physiotherapy within the last 12 months following lower limb injuries. Moments of maximal strength (MMS), isometric torque (IT), and peak torque (PT) were measured under static and isokinetic conditions using the Humac Norm System. In the first group, IT measurements were performed during the 13th and 21st week of physiotherapy, while PT measurements were performed during the 16th and 21st weeks of physiotherapy following ACLR. In the control groups (II and III) the measurements were performed once. Results In the first group, the IT (13 weeks) and PT (16 weeks) values of internal tibial rotator muscles, obtained from the operated extremities were significantly lower than the values obtained from the uninvolved knees and the control group results. During the 21st week of physiotherapy, the results obtained for IT and PT in patients after ACLR were similar to the values obtained from the uninvolved knees and the results of the second group subjects. Conclusions The 21-week physiotherapy in ACLR patients favorably affected the PT values of tibial rotator muscles of the operated knees. In the third group, the IT values did not indicate a complete improvement after 12 months without systematic physiotherapy. PMID:21873950

  10. Wnt7a stimulates myogenic stem cell motility and engraftment resulting in improved muscle strength.

    PubMed

    Bentzinger, C Florian; von Maltzahn, Julia; Dumont, Nicolas A; Stark, Danny A; Wang, Yu Xin; Nhan, Kevin; Frenette, Jérôme; Cornelison, D D W; Rudnicki, Michael A

    2014-04-14

    Wnt7a/Fzd7 signaling stimulates skeletal muscle growth and repair by inducing the symmetric expansion of satellite stem cells through the planar cell polarity pathway and by activating the Akt/mTOR growth pathway in muscle fibers. Here we describe a third level of activity where Wnt7a/Fzd7 increases the polarity and directional migration of mouse satellite cells and human myogenic progenitors through activation of Dvl2 and the small GTPase Rac1. Importantly, these effects can be exploited to potentiate the outcome of myogenic cell transplantation into dystrophic muscles. We observed that a short Wnt7a treatment markedly stimulated tissue dispersal and engraftment, leading to significantly improved muscle function. Moreover, myofibers at distal sites that fused with Wnt7a-treated cells were hypertrophic, suggesting that the transplanted cells deliver activated Wnt7a/Fzd7 signaling complexes to recipient myofibers. Taken together, we describe a viable and effective ex vivo cell modulation process that profoundly enhances the efficacy of stem cell therapy for skeletal muscle. PMID:24711502

  11. Wnt7a stimulates myogenic stem cell motility and engraftment resulting in improved muscle strength

    PubMed Central

    Bentzinger, C. Florian; von Maltzahn, Julia; Dumont, Nicolas A.; Stark, Danny A.; Wang, Yu Xin; Nhan, Kevin; Frenette, Jérôme; Cornelison, DDW

    2014-01-01

    Wnt7a/Fzd7 signaling stimulates skeletal muscle growth and repair by inducing the symmetric expansion of satellite stem cells through the planar cell polarity pathway and by activating the Akt/mTOR growth pathway in muscle fibers. Here we describe a third level of activity where Wnt7a/Fzd7 increases the polarity and directional migration of mouse satellite cells and human myogenic progenitors through activation of Dvl2 and the small GTPase Rac1. Importantly, these effects can be exploited to potentiate the outcome of myogenic cell transplantation into dystrophic muscles. We observed that a short Wnt7a treatment markedly stimulated tissue dispersal and engraftment, leading to significantly improved muscle function. Moreover, myofibers at distal sites that fused with Wnt7a-treated cells were hypertrophic, suggesting that the transplanted cells deliver activated Wnt7a/Fzd7 signaling complexes to recipient myofibers. Taken together, we describe a viable and effective ex vivo cell modulation process that profoundly enhances the efficacy of stem cell therapy for skeletal muscle. PMID:24711502

  12. The relationship of birthweight, muscle size at birth and postnatal growth to grip strength in 9 year-old Indian children: findings from the Mysore Parthenon Study

    PubMed Central

    Barr, James G; Veena, Sargoor R; Kiran, K N; Wills, Andrew K; Winder, Nicola R; Kehoe, Sarah; Fall, Caroline HD; Sayer, Avan A; Krishnaveni, Ghattu V

    2012-01-01

    Fetal development may permanently affect muscle function. Indian newborns have a low mean birthweight, predominantly due to low lean tissue and muscle mass. We aimed to examine the relationship of birthweight, and arm muscle area (AMA) at birth and post-natal growth to hand-grip strength in Indian children. Grip strength was measured in 574 children aged 9 years, who had detailed anthropometry at birth and every 6-12 months post-natally. Mean (standard deviation (SD)) birthweight was 2863 (446) g. At 9 years, the children were short (mean height SD −0.6) and light (mean weight SD −1.1) compared with the World Health Organization growth reference. Mean (SD) grip strength was 12.7 (2.2) kg (boys) and 11.0 (2.0) kg (girls). Weight, length and AMA at birth, but not skinfold measurements at birth, were positively related to 9-year grip strength (β=0.40 kg per standard deviation increase in birthweight, p<0.001; and β=0.41 kg per standard deviation increase in AMA, p<0.001). Grip strength was positively related to 9-year height, body mass index and AMA and to gains in these measurements from birth to 2 years, 2-5 years and 5-9 years (p<0.001 for all). The associations between birth size and grip strength were attenuated but remained statistically significant for AMA after adjusting for 9-year size. We conclude that larger overall size and muscle mass at birth are associated with greater muscle strength in childhood, and that this is mediated mainly through greater post-natal size. Poorer muscle development in utero is associated with reduced childhood muscle strength. PMID:23750316

  13. Effect of the vibration board on the strength of ankle dorsal and plantar flexor muscles: a preliminary randomized controlled study.

    PubMed

    Costantino, Cosimo; Pogliacomi, Francesco; Soncini, Giovanni

    2006-04-01

    Aim of this preliminary work is to study the effects of the vibration board on the strength of dorsal and plantar flexor muscles of the ankle through a randomized and controlled observation. Sixteen sedentary right-handed females, ranged from 20 to 30 years of age, were selected; they were not affected by previous ankle sprains and were divided into two randomized groups. The study group followed a vibration board training in the orthostatic position with a 60 degrees flexion of the knee in order to direct its mechanical impulses to the inferior limbs. Each patient of the study group performed daily, for 2 weeks, 10 repetitions that lasted 1 minute each (25 hertz of frequency). The control group followed a training protocol including 10 daily sessions for 2 weeks. Each session included 3 series of 10 repetitions of flexi-extension of the foot versus an opposite resistance of an elastic band, 60 centimetres long, that was stretched till 100 cm. Both groups were tested before and after these training programmes by Biodex isokinetic dynamometer in order to quantify the strength of the plantar and dorsal flexor muscles of the dominant ankle. Peak torque, power and total work of the dorsal and plantar flexor muscles were assessed. A power test at an angular velocity of 60 degrees/sec for five repetitions and a resistance test at an angular velocity of 180 degrees/sec. for 20 repetitions were performed. After the final isokinetic test, the results were submitted to a statistic evaluation (T test of Student) in order to analyze any possible significant differences (p < 0.05) among the initial and final values before and after the treatment. The results of the study group compared to the control group showed a significant increase in the power of the dorsal flexor muscles at an angular velocity of 60 degrees/sec and in the peak torque, power and total work of the plantar flexor muscles at an angular velocity of 60 degrees/sec and 180 degrees/sec. We conclude that the use

  14. Effects of humeral head compression taping on the isokinetic strength of the shoulder external rotator muscle in patients with rotator cuff tendinitis

    PubMed Central

    Kim, Moon-Hwan; Oh, Jae-Seop

    2015-01-01

    [Purpose] The purpose of this study was to examine the effects of humeral head compression taping (HHCT) on the strength of the shoulder external rotator muscle in patients with rotator cuff tendinitis. [Subjects and Methods] Twenty patients with rotator cuff tendinitis were recruited. The shoulder external rotator strength was measured using a Biodex isokinetic dynamometer system. A paired t-test was performed to evaluate within-group differences in the strength of the shoulder external rotator muscle. [Results] Significantly higher shoulder external rotator peak torque and peak torque per body weight were found in the HHCT condition than in the no-taping condition. [Conclusion] HHCT may effectively increase the shoulder external rotator muscle strength in patients with rotator cuff tendinitis. PMID:25642053

  15. Is repetition failure critical for the development of muscle hypertrophy and strength?

    PubMed

    Sampson, J A; Groeller, H

    2016-04-01

    This investigation sought to determine the effect of resistance training to failure on functional, structural and neural elbow flexor muscle adaptation. Twenty-eight males completed a 4-week familiarization period and were then counterbalanced on the basis of responsiveness across; non-failure rapid shortening (RS; rapid concentric, 2 s eccentric), non-failure stretch-shortening (SSC; rapid concentric, rapid eccentric), and failure control (C, 2 s concentric, 2 s eccentric), for a 12-week unilateral elbow flexor resistance training regimen, 3 × week using 85% of one repetition maximum (1RM). 1RM, maximal voluntary contraction (MVC), muscle cross-sectional area (CSA), and muscle activation (EMGRMS ) of the agonist, antagonist, and stabilizer muscles were assessed before and after the 12-week training period. The average number of repetitions per set was significantly lower in RS 4.2 [confidence interval (CI): 4.2, 4.3] and SSC 4.2 (CI: 4.2, 4.3) compared with C 6.1 (CI: 5.8, 6.4). A significant increase in 1RM (30.5%), MVC (13.3%), CSA (11.4%), and agonist EMGRMS (22.1%) was observed; however, no between-group differences were detected. In contrast, antagonist EMGRMS increased significantly in SSC (40.5%) and C (23.3%), but decreased in RS (13.5%). Similar adaptations across the three resistance training regimen suggest repetition failure is not critical to elicit significant neural and structural changes to skeletal muscle. PMID:25809472

  16. Effects of Pilates mat exercises on muscle strength and on pulmonary function in patients with cystic fibrosis*

    PubMed Central

    Franco, Caroline Buarque; Ribeiro, Antonio Fernando; Morcillo, André Moreno; Zambon, Mariana Porto; Almeida, Marina Buarque; Rozov, Tatiana

    2014-01-01

    OBJECTIVE: To analyze the effects of Pilates mat exercises in patients with cystic fibrosis (CF). METHODS: This was a clinical trial involving 19 CF patients recruited from either the CF Outpatient Clinic of the State University at Campinas Hospital de Clínicas or the Children's Institute of the University of São Paulo School of Medicine Hospital das Clínicas. All of the patients performed Pilates mat exercises for four months (one 60-min session per week). The variables studied (before and after the intervention) were respiratory muscle strength, MIP, MEP, FVC, and FEV1. RESULTS: After the intervention, MIP was significantly higher in the male patients (p = 0.017), as were MIP and MEP in the female patients (p = 0.005 and p = 0.007, respectively). There were no significant differences between the pre- and post-intervention values of FVC or FEV1, neither in the sample as a whole nor among the patients of either gender. CONCLUSIONS: Our results show that Pilates mat exercises have beneficial effects on respiratory muscle strength in CF patients. PMID:25410840

  17. Evaluation of muscle strength and motor abilities in children with type II and III spinal muscle atrophy treated with valproic acid

    PubMed Central

    2011-01-01

    Background Spinal muscular atrophy (SMA) is an autosomal recessive disorder that affects the motoneurons of the spinal anterior horn, resulting in hypotonia and muscle weakness. The disease is caused by deletion or mutation in the telomeric copy of SMN gene (SMN1) and clinical severity is in part determined by the copy number of the centromeric copy of the SMN gene (SMN2). The SMN2 mRNA lacks exon 7, resulting in a production of lower amounts of the full-length SMN protein. Knowledge of the molecular mechanism of diseases has led to the discovery of drugs capable of increasing SMN protein level through activation of SMN2 gene. One of these drugs is the valproic acid (VPA), a histone deacetylase inhibitor. Methods Twenty-two patients with type II and III SMA, aged between 2 and 18 years, were treated with VPA and were evaluated five times during a one-year period using the Manual Muscle Test (Medical Research Council scale-MRC), the Hammersmith Functional Motor Scale (HFMS), and the Barthel Index. Results After 12 months of therapy, the patients did not gain muscle strength. The group of children with SMA type II presented a significant gain in HFMS scores during the treatment. This improvement was not observed in the group of type III patients. The analysis of the HFMS scores during the treatment period in the groups of patients younger and older than 6 years of age did not show any significant result. There was an improvement of the daily activities at the end of the VPA treatment period. Conclusion Treatment of SMA patients with VPA may be a potential alternative to alleviate the progression of the disease. Trial Registration ClinicalTrials.gov: NCT01033331 PMID:21435220

  18. Efficacy of phosphatidic acid ingestion on lean body mass, muscle thickness and strength gains in resistance-trained men

    PubMed Central

    2012-01-01

    Background Phosphatidic acid (PA) has been reported to activate the mammalian target of rapamycin (mTOR) signaling pathway and is thought to enhance the anabolic effects of resistance training. The purpose of this pilot study was to examine if oral phosphatidic acid administration can enhance strength, muscle thickness and lean tissue accruement during an 8-week resistance training program. Methods Sixteen resistance-trained men were randomly assigned to a group that either consumed 750 mg of PA (n = 7, 23.1 ± 4.4 y; 176.7 ± 6.7 cm; 86.5 ± 21.2 kg) or a placebo (PL, n = 9, 22.5 ± 2.0 y; 179.8 ± 5.4 cm; 89.4 ± 13.6 kg) group. During each testing session subjects were assessed for strength (one repetition maximum [1-RM] bench press and squat) and body composition. Muscle thickness and pennation angle were also measured in the vastus lateralis of the subject’s dominant leg. Results Subjects ingesting PA demonstrated a 12.7% increase in squat strength and a 2.6% increase in LBM, while subjects consuming PL showed a 9.3% improvement in squat strength and a 0.1% change in LBM. Although parametric analysis was unable to demonstrate significant differences, magnitude based inferences indicated that the Δ change in 1-RM squat showed a likely benefit from PA on increasing lower body strength and a very likely benefit for increasing lean body mass (LBM). Conclusions Results of this study suggest that a combination of a daily 750 mg PA ingestion, combined with a 4-day per week resistance training program for 8-weeks appears to have a likely benefit on strength improvement, and a very likely benefit on lean tissue accruement in young, resistance trained individuals. PMID:23035701

  19. Effects of the lower extremities muscle activation during muscular strength training on an unstable platform with magneto-rheological dampers

    NASA Astrophysics Data System (ADS)

    Piao, YongJun; Choi, YounJung; Kim, JungJa; Kwan, TaeKyu; Kim, Nam-Gyun

    2009-03-01

    Adequate postural balance depends on the spatial and temporal integration of vestibular, visual, and somatosensory information. Especially, the musculoskeletal function (range of joint, flexibility of spine, muscular strength) is essential in maintaining the postural balance. Muscular strength training methods include the use of commercialized devices and repeatable resistance training tools (rubber band, ball, etc). These training systems cost high price and can't control of intensity. Thus we suggest a new training system which can adjust training intensity and indicate the center of pressure of a subject while the training was passively controlled by applying controlled electric current to the Magneto- Rheological damper. And we performed experimental studies on the muscular activities in the lower extremities during maintaining, moving and pushing exercises on an unstable platform with Magneto rheological dampers. A subject executed the maintaining, moving and pushing exercises which were displayed in a monitor. The electromyographic signals of the eight muscles in lower extremities were recorded and analyzed in the time and frequency domain: the muscles of interest were rectus femoris, biceps femoris, tensor fasciae latae, vastus lateralis, vastus medialis, gastrocnemius, tibialis anterior, and soleus. The experimental results showed the difference of muscular activities at the four moving exercises and the nine maintaining exercises. The rate of the increase in the muscular activities was affected by the condition of the unstable platform with MR dampers for the maintaining and moving exercises. The experimental results suggested the choice of different maintaining and moving exercises could selectively train different muscles with varying intensity. Furthermore, the findings also suggested the training using this system can improve the ability of postural balance.

  20. An electromyographic study of strength and upper extremity muscle activity in simulated meat cutting tasks.

    PubMed

    Grant, K A; Habes, D J

    1997-04-01

    Meat cutting has long been associated with a high incidence rate of upper extremity musculoskeletal disorders. This study examined upper extremity muscle activities and force exertion capabilities to identify postures which have potential for causing overexertion injuries. Fifteen subjects exerted force against a handle in postures similar to those observed in the meatpacking industry. Exertion level, direction of exertion, handle height, reach distance and grip type were varied. Activity in the posterior deltoid, biceps brachii, triceps brachii, extensor digitorum and flexor digitorum superficialis was monitored via surface electromyography (EMG). The ratio of normalized EMG activity to force produced during the exertion was computed for each muscle under each condition. The results showed that handle position had a significant effect on force exertion capability and the EMG/force ratio in all muscles. Force exertion capability was maximized, and the EMG/force ratio was generally minimized when participants pulled downward on a handle positioned at full arm's reach above the shoulder. For vertical cuts, force decreased and muscle activity generally increased as the handle height was lowered. For horizontal cuts, the full reach distance tended to allow greater force exertion with lower EMG/force ratios. The stab grip also tended to be associated with higher forces and lower EMG/force ratios than the slice grip. This study supports the premise that musculoskeletal stresses in meatpacking tasks can be altered through tool and workstation redesign. The data provided herein may be useful in selecting design modifications that reduce biomechanical stress on the upper extremities. PMID:9414348

  1. Relationships between power and strength of the upper and lower limb muscles and throwing velocity in male handball players.

    PubMed

    Chelly, Mohamed Souhaiel; Hermassi, Souhail; Shephard, Roy J

    2010-06-01

    This study aimed to investigate relationships between peak power (PP) as measured by upper limb (PPUL) and lower limb (PPLL) force-velocity tests, maximal upper limb force assessed by 1 repetition maximum bench press (1RMBP), and pullover (1RMPO) exercises, estimates of local muscle volume and 3-step running handball throwing velocity (T3-Steps). Fourteen male handball players volunteered for the investigation (age: 19.6+/-0.6 years; body mass: 86.7+/-12.9 kg; and height 1.87+/-0.07 m). Lower and upper limb force-velocity tests were performed on appropriately modified forms of a Monark cycle ergometer, with measurement of PPUL and PPLL, and the corresponding respective maximal forces (F0UL and F0LL) and velocities (V0UL and V0LL). T3-Steps was assessed using a radar Stalker ATS system. Muscle volumes of the upper and lower limbs were estimated with a standard anthropometric kit. T3-Steps was closely related to absolute PPUL and to F0UL (r=0.69, p<0.01 for both relationships). T3-Steps was also moderately related to 1RMBP and 1RMPO (r=0.56, p<0.05; r=0.55, p<0.05 respectively), and to PPLL and F0LL (r=0.56, p<0.05; r=0.62, p<0.05, respectively). When PPLL was expressed per unit of limb muscle volume, the relationship with T3-Steps disappeared. This suggests the importance of muscle volume to performance in throwing events. Force-velocity data may prove useful in regulating conditioning and rehabilitation programs for handball players. Our results also highlight the contribution of both the lower and the upper limbs to handball throwing velocity, suggesting the need for coaches to include upper and lower limb strength and power programs when improving the throwing velocity of handball players. PMID:20508448

  2. Assessment of the effect of pelvic floor exercises on pelvic floor muscle strength using ultrasonography in patients with urinary incontinence: a prospective randomized controlled trial.

    PubMed

    Tosun, Ozge Celiker; Solmaz, Ulas; Ekin, Atalay; Tosun, Gokhan; Gezer, Cenk; Ergenoglu, Ahmet Mete; Yeniel, Ahmet Ozgur; Mat, Emre; Malkoc, Mehtap; Askar, Niyazi

    2016-01-01

    [Purpose] The aim of this study was to evaluate whether the effect of pelvic floor exercises on pelvic floor muscle strength could be detected via ultrasonography in patients with urinary incontinence. [Subjects and Methods] Of 282 incontinent patients, 116 participated in the study and were randomly divided into a pelvic floor muscle training (n=65) group or control group (n=51). The pelvic floor muscle training group was given pelvic floor exercise training for 12 weeks. Both groups were evaluated at the beginning of the study and after 12 weeks. Abdominal ultrasonography measurements in transverse and longitudinal planes, the PERFECT scheme, perineometric evaluation, the stop test, the stress test, and the pad test were used to assess pelvic floor muscle strength in all cases. [Results] After training, the PERFECT, perineometry and transabdominal ultrasonography measurements were found to be significantly improved, and the stop test and pad test results were significantly decreased in the pelvic floor muscle training group, whereas no difference was observed in the control group. There was a positive correlation between the PERFECT force measurement scale and ultrasonography force measurement scale before and after the intervention in the control and pelvic floor muscle training groups (r=0.632 and r=0.642, respectively). [Conclusion] Ultrasonography can be used as a noninvasive method to identify the change in pelvic floor muscle strength with exercise training. PMID:27065519

  3. Assessment of the effect of pelvic floor exercises on pelvic floor muscle strength using ultrasonography in patients with urinary incontinence: a prospective randomized controlled trial

    PubMed Central

    Tosun, Ozge Celiker; Solmaz, Ulas; Ekin, Atalay; Tosun, Gokhan; Gezer, Cenk; Ergenoglu, Ahmet Mete; Yeniel, Ahmet Ozgur; Mat, Emre; Malkoc, Mehtap; Askar, Niyazi

    2016-01-01

    [Purpose] The aim of this study was to evaluate whether the effect of pelvic floor exercises on pelvic floor muscle strength could be detected via ultrasonography in patients with urinary incontinence. [Subjects and Methods] Of 282 incontinent patients, 116 participated in the study and were randomly divided into a pelvic floor muscle training (n=65) group or control group (n=51). The pelvic floor muscle training group was given pelvic floor exercise training for 12 weeks. Both groups were evaluated at the beginning of the study and after 12 weeks. Abdominal ultrasonography measurements in transverse and longitudinal planes, the PERFECT scheme, perineometric evaluation, the stop test, the stress test, and the pad test were used to assess pelvic floor muscle strength in all cases. [Results] After training, the PERFECT, perineometry and transabdominal ultrasonography measurements were found to be significantly improved, and the stop test and pad test results were significantly decreased in the pelvic floor muscle training group, whereas no difference was observed in the control group. There was a positive correlation between the PERFECT force measurement scale and ultrasonography force measurement scale before and after the intervention in the control and pelvic floor muscle training groups (r=0.632 and r=0.642, respectively). [Conclusion] Ultrasonography can be used as a noninvasive method to identify the change in pelvic floor muscle strength with exercise training. PMID:27065519

  4. Tibialis Anterior muscle coherence during controlled voluntary activation in patients with spinal cord injury: diagnostic potential for muscle strength, gait and spasticity

    PubMed Central

    2014-01-01

    inversely with 40-60 Hz. Conclusion Analysis of intramuscular 15-30 Hz TA coherence during isometric activation at 100% of MVT is related to muscle strength and gait function following incomplete SCI. In contrast several spasticity symptoms correlated negatively with 10-16 Hz and 40-60 Hz TA coherence during isometric activation at 100% MVT. Validation of the diagnostic potential of TA coherence estimation as a reliable and comprehensive measure of muscle strength, gait and spasticity should facilitate SCI neurorehabilation. PMID:24594207

  5. The Effects of Multiple-Joint Isokinetic Resistance Training on Maximal Isokinetic and Dynamic Muscle Strength and Local Muscular Endurance

    PubMed Central

    Ratamess, Nicholas A.; Beller, Noah A.; Gonzalez, Adam M.; Spatz, Gregory E.; Hoffman, Jay R.; Ross, Ryan E.; Faigenbaum, Avery D.; Kang, Jie

    2016-01-01

    The transfer of training effects of multiple-joint isokinetic resistance training to dynamic exercise performance remain poorly understood. Thus, the purpose of the present study was to investigate the magnitude of isokinetic and dynamic one repetition-maximum (1RM) strength and local muscular endurance increases after 6 weeks of multiple-joint isokinetic resistance training. Seventeen women were randomly assigned to either an isokinetic resistance training group (IRT) or a non-exercising control group (CTL). The IRT group underwent 6 weeks of training (2 days per week) consisting of 5 sets of 6-10 repetitions at 75-85% of subjects’ peak strength for the isokinetic chest press and seated row exercises at an average linear velocity of 0.15 m s-1 [3-sec concentric (CON) and 3-sec eccentric (ECC) phases]. Peak CON and ECC force during the chest press and row, 1RM bench press and bent-over row, and maximum number of modified push-ups were assessed pre and post training. A 2 x 2 analysis of variance with repeated measures and Tukey’s post hoc tests were used for data analysis. The results showed that 1RM bench press (from 38.6 ± 6.7 to 43.0 ± 5.9 kg), 1RM bent-over row (from 40.4 ± 7.7 to 45.5 ± 7.5 kg), and the maximal number of modified push-ups (from 39.5 ± 13.6 to 55.3 ± 13.1 repetitions) increased significantly only in the IRT group. Peak isokinetic CON and ECC force in the chest press and row significantly increased in the IRT group. No differences were shown in the CTL group for any measure. These data indicate 6 weeks of multiple-joint isokinetic resistance training increases dynamic muscle strength and local muscular endurance performance in addition to specific isokinetic strength gains in women. Key points Multiple-joint isokinetic resistance training increases dynamic maximal muscular strength, local muscular endurance, and maximal isokinetic strength in women. Multiple-joint isokinetic resistance training increased 1RM strength in the bench press

  6. Acute and chronic responses of the upper airway to inspiratory loading in healthy awake humans: an MRI study.

    PubMed

    How, Stephen C; McConnell, Alison K; Taylor, Bryan J; Romer, Lee M

    2007-08-01

    We assessed upper airway responses to acute and chronic inspiratory loading. In Experiment I, 11 healthy subjects underwent T(2)-weighted magnetic resonance imaging (MRI) of upper airway dilator muscles (genioglossus and geniohyoid) before and up to 10 min after a single bout of pressure threshold inspiratory muscle training (IMT) at 60% maximal inspiratory mouth pressure (MIP). T(2) values for genioglossus and geniohyoid were increased versus control (p<0.001), suggesting that these airway dilator muscles are activated in response to acute IMT. In Experiment II, nine subjects underwent 2D-Flash sequence MRI of the upper airway during quiet breathing and while performing single inspirations against resistive loads (10%, 30% and 50% MIP); this procedure was repeated after 6 weeks of IMT. Lateral narrowing of the upper airway occurred at all loads, whilst anteroposterior narrowing occurred at the level of the laryngopharynx at loads > or =30% MIP. Changes in upper airway morphology and narrowing after IMT were undetectable using MRI. PMID:17341450

  7. Proposal of Method for Control of Muscle Activation Level for Limbs during Motion and Application of this Method in Strength Training

    NASA Astrophysics Data System (ADS)

    Komada, Satoshi; Murakami, Yosuke; Hirai, Junji

    With an increase in the number of elderly people in our society, the need for equipments that ensure activities of daily living and that can be used in strength training for reducing the need for nursing care is increasing. In this paper, we propose a method for controlling the level of muscle activation for a particular muscle group without EMG sensors; the force exerted by the tips of the limbs during motion is used to control the level of muscle activation. The method is based on a musculoskeletal model for limbs called functionally different effective muscles of three antagonistic pairs of six muscles in 2D space. Hill's equation is incorporated in the method to consider force-velocity characteristics of muscles. EMG measurement results for two muscles under isokinetic contraction in the lower limbs of a subject show that difference between the achieved activation level and the desired activation level is less than the error of the output force distribution. Moreover, the control method is applied to strength training. A manipulator that can facilitate the isokinetic contraction with more than the desired activation level for a specific muscle group is developed.

  8. Caffeine-induced increase in voluntary activation and strength of the quadriceps muscle during isometric, concentric and eccentric contractions.

    PubMed

    Behrens, Martin; Mau-Moeller, Anett; Weippert, Matthias; Fuhrmann, Josefin; Wegner, Katharina; Skripitz, Ralf; Bader, Rainer; Bruhn, Sven

    2015-01-01

    This study investigated effects of caffeine ingestion (8 mg/kg) on maximum voluntary torque (MVT) and voluntary activation of the quadriceps during isometric, concentric and eccentric contractions. Fourteen subjects ingested caffeine and placebo in a randomized, controlled, counterbalanced, double-blind crossover design. Neuromuscular tests were performed before and 1 h after oral caffeine and placebo intake. MVTs were measured and the interpolated twitch technique was applied during isometric, concentric and eccentric contractions to assess voluntary activation. Furthermore, normalized root mean square of the EMG signal was calculated and evoked spinal reflex responses (H-reflex evoked at rest and during weak isometric voluntary contraction) as well as twitch torques were analyzed. Caffeine increased MVT by 26.4 N m (95%CI: 9.3-43.5 N m, P = 0.004), 22.5 N m (95%CI: 3.1-42.0 N m, P = 0.025) and 22.5 N m (95%CI: 2.2-42.7 N m, P = 0.032) for isometric, concentric and eccentric contractions. Strength enhancements were associated with increases in voluntary activation. Explosive voluntary strength and voluntary activation at the onset of contraction were significantly increased following caffeine ingestion. Changes in spinal reflex responses and at the muscle level were not observed. Data suggest that caffeine ingestion induced an acute increase in voluntary activation that was responsible for the increased strength regardless of the contraction mode. PMID:25969895

  9. Evaluation of Proximal Joint Kinematics and Muscle Strength Following ACL Reconstruction Surgery in Female Athletes

    PubMed Central

    Noehren, Brian; Abraham, Autumn; Curry, Melisa; Johnson, Darren; Ireland, Mary Lloyd

    2015-01-01

    Background\\Purpose Despite the intense focus on outcomes following an anterior cruciate ligament (ACL) reconstruction, it is not yet known whether unresolved abnormal hip and trunk neuromuscular control exists. The purpose of this study was to compare trunk and hip kinematics during running, hip abductor and external rotator strength, and trunk control between females who had undergone an ACL reconstruction and healthy control participants. Methods We compared 20 ACL reconstructed females to 20 healthy individuals, measuring abduction and external rotation strength, a trunk control test, and performed an instrumented gait evaluation during running. Comparisons between groups were made for non-sagittal peak hip angles, forward trunk lean, trunk ipsilateral lean at initial contact, trunk control and hip abduction and external rotation strength. Results We found no significant differences in hip abduction (p = 0.25), hip external rotation strength (p = 0.63), peak hip adduction (p = 0.11) or hip internal rotation angle (p = 0.47). The ACL group did have a significantly greater ipsilateral trunk lean (p = 0.028), forward lean (p = 0.004), and had higher errors on the trunk stability test (p = 0.007). Conclusion We found significant differences in trunk control, suggesting further attention should be devoted to this component of rehabilitation. PMID:25044305

  10. Effects of Strength Training on Muscle Development in Prepubescent, Pubescent, and Postpubescent Males.

    ERIC Educational Resources Information Center

    Pfeiffer, Ronald D.; Francis, Rulon S.

    1986-01-01

    Thirty-three males from ages 8 to 21 years participated in a nine-week resistive exercise program to test the hypothesis that pubescent males respond better to strength training than older or younger males do. Results are discussed. (Author/MT)

  11. Strength exercise improves muscle mass and hepatic insulin sensitivity in obese youth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Data on the metabolic effects of resistance exercise (strength training) in adolescents are limited. The objective of this study was to determine whether a controlled resistance exercise program without dietary intervention or weight loss reduces body fat accumulation, increases lean body mass, and ...

  12. Effect of Transcutaneous Electrical Nerve Stimulation, Cold, and a Combination Treatment on Pain, Decreased Range of Motion, and Strength Loss Associated with Delayed Onset Muscle Soreness

    PubMed Central

    Denegar, Craig R.; Perrin, David H.

    1992-01-01

    Athletic trainers have a variety of therapeutic agents at their disposal to treat musculoskeletal pain, but little objective evidence exists of the efficacy of the modalities they use. In this study, delayed onset muscle soreness (DOMS) served as a model for musculoskeletal injury in order to: (1) compare the changes in perceived pain, elbow extension range of motion, and strength loss in subjects experiencing DOMS in the elbow flexor muscle group following a single treatment with either transcutaneous electrical nerve stimulation (TENS), cold, a combination of TENS and cold, sham TENS, or 20 minutes of rest; (2) compare the effects of combining static stretching with these treatments; and (3) determine if decreased pain is accompanied by a restoration of strength. DOMS was induced in the non-dominant elbow flexor muscle group in 40 females (age = 22.0 ± 4.3 yr) with repeated eccentric contractions. Forty-eight hours following exercise, all subjects presented with pain, decreased elbow extension range of motion, and decreased strength consistent with DOMS. Subjects were randomly assigned to 20-minute treatments followed by static stretching. Cold, TENS, and the combined treatment resulted in significant decreases in perceived pain. Treatments with cold resulted in a significant increase in elbow extension range of motion. Static stretching also significantly reduced perceived pain. Only small, nonsignificant changes in muscle strength were observed following treatment or stretching, regardless of the treatment group. These results suggest that the muscle weakness associated with DOMS is not the result of inhibition caused by pain. The results suggest that these modalities are effective in treating the pain and muscle spasm associated with DOMS, and that decreased pain may not be an accurate indicator of the recovery of muscle strength. PMID:16558162

  13. The Influence of Oral L-Glutamine Supplementation on Muscle Strength Recovery and Soreness Following Unilateral Knee Extension Eccentric Exercise.

    PubMed

    Legault, Zachary; Bagnall, Nicholas; Kimmerly, Derek S

    2015-10-01

    The study aimed to examine the effects that L-glutamine supplementation has on quadriceps muscle strength and soreness ratings following eccentric exercise. It was hypothesized that glutamine ingestion would quicken the recovery rate of peak force production and decrease muscle soreness ratings over a 72-hr recovery period. Sixteen healthy participants (8♀/8♂; 22 ± 4 years) volunteered in a double-blind, randomized, placebo-controlled crossover study. Supplement conditions consisted of isoenergetic placebo (maltodextrin, 0.6 g·kg-1·day-1) and L-glutamine (0.3 g·kg-1·day-1 + 0.3 g·kg-1·day-1 maltodextrin) ingestion once per day over 72 hr. Knee extensor peak torque at 0°, 30°, and 180° per second and muscle soreness were measured before, immediately following, 24, 48, and 72 hr posteccentric exercise. Eccentric exercise consisted of 8 sets (10 repetitions/set) of unilateral knee extension at 125% maximum concentric force with 2-min rest intervals. L-glutamine resulted in greater relative peak torque at 180°/sec both immediately after (71 ± 8% vs. 66 ± 9%), and 72 hr (91 ± 8% vs. 86 ± 7%) postexercise (all, p < .01). In men, L-glutamine produced greater (p < .01) peak torques at 30°/ sec postexercise. Men also produced greater normalized peak torques at 30°/sec (Nm/kg) in the L-glutamine condition than women (all, p < .05). In the entire sample, L-glutamine resulted in lower soreness ratings at 24 (2.8 ± 1.2 vs. 3.4 ± 1.2), 48 (2.6 ± 1.4 vs. 3.9 ± 1.2), and 72 (1.7 ± 1.2 vs. 2.9 ± 1.3) hr postexercise (p < .01). The L-glutamine supplementation resulted in faster recovery of peak torque and diminished muscle soreness following eccentric exercise. The effect of L-glutamine on muscle force recovery may be greater in men than women. PMID:25811544

  14. Estimation of muscle strength during motion recognition using multichannel surface EMG signals.

    PubMed

    Nagata, Kentaro; Nakano, Takemi; Magatani, Kazushige; Yamada, Masafumi

    2008-01-01

    The use of kinesiological electromyography is established as an evaluation tool for various kinds of applied research, and surface electromyogram (SEMG) has been widely used as a control source for human interfaces such as in a myoelectric prosthetic hand (we call them 'SEMG interfaces'). It is desirable to be able to control the SEMG interfaces with the same feeling as body movement. The existing SEMG interface mainly focuses on how to achieve accurate recognition of the intended movement. However, detecting muscular strength and reduced number of electrodes are also an important factor in controlling them. Therefore, our objective in this study is the development of and the estimation method for muscular strength that maintains the accuracy of hand motion recognition to reflect the result of measured power in a controlled object. Although the muscular strength can be evaluated by various methods, in this study a grasp force index was applied to evaluate the muscular strength. In order to achieve our objective, we directed our attention to measuring all valuable information for SEMG. This work proposes an application method of two simple linear models, and the selection method of an optimal electrode configuration to use them effectively. Our system required four SEMG measurement electrodes in which locations differed for every subject depending on the individual's characteristics, and those were selected from a 96ch multi electrode using the Monte Carlo method. From the experimental results, the performance in six normal subjects indicated that the recognition rate of four motions were perfect and the grasp force estimated result fit well with the actual measurement result. PMID:19162665

  15. Effect of unilateral exercise on spinal and pelvic deformities, and isokinetic trunk muscle strength

    PubMed Central

    Jeon, Kyoungkyu; Kim, Soonyoung

    2016-01-01

    [Purpose] The purpose of this study was to collect basic data regarding the prevention of spinal and pelvic deformities by investigating the spinal shape and muscular function characteristics of imbalance reduction and functional improvement following asymmetric activities. [Subjects and Methods] The subjects were 14 archery athletes who mostly perform unilateral motion with spinal and pelvic pain, and 19 healthy subjects. All the participants were evaluated using spinal structure analysis and for 60°/sec isokinetic muscular strength of the trunk. [Results] Between the two groups, there were significant differences in the interaction effect of trunk inclination deformities, and flexor and extensor 60°/sec isokinetic muscular strength of the trunk. Also, the main effects of gender comparison showed significant differences in the trunk inclination deformities, pelvic rotation deformities, lordosis angles, and flexor and extensor 60 ˚/sec isokinetic muscular strengths of the trunk. [Conclusion] The basic data obtained in this study can be used to help develop a strategic exercise program for improving unilateral movement and malalignment of the spine and pelvis. PMID:27134369

  16. Stroboscopic and acoustic measures of inspiratory phonation.

    PubMed

    Kelly, C L; Fisher, K V

    1999-09-01

    Inspiratory phonation (IP) is the production of voice as air is taken into the lungs. Although IP is promoted as a laryngeal assessment and voice treatment technique, it has been described quantitatively in very few speakers. This study quantified changes in laryngeal adduction, fundamental frequency, and intensity during IP relative to expiratory phonation (EP). We hypothesized that IP would increase laryngeal abduction and fundamental frequency. The experiment was a within-subjects, repeated measures design with each subject serving as her own control. Participants were 10 females (ages 19-50 years) who underwent simultaneous transoral videostrobolaryngoscopy and acoustic voice recording. We found that membranous vocal fold contact decreased significantly during IP relative to EP, while the trends for change of ventricular fold squeeze during IP varied across individuals. Vocal fundamental frequency increased significantly during IP relative to EP, but intensity did not vary consistently across conditions. Without teaching or coaching, changes that occurred during IP did not carry over to EP produced immediately following IP within the same respiratory cycle. PMID:10498055

  17. Association of Quadriceps Muscle Fat With Isometric Strength Measurements in Healthy Males Using Chemical Shift Encoding-Based Water-Fat Magnetic Resonance Imaging

    PubMed Central

    Baum, Thomas; Inhuber, Stephanie; Dieckmeyer, Michael; Cordes, Christian; Ruschke, Stefan; Klupp, Elisabeth; Jungmann, Pia M.; Farlock, Rosanna; Eggers, Holger; Kooijman, Hendrik; Rummeny, Ernst J.; Schwirtz, Ansgar; Kirschke, Jan S.; Karampinos, Dimitrios C.

    2016-01-01

    Abstract Magnetic resonance–based assessment of quadriceps muscle fat has been proposed as surrogate marker in sarcopenia, osteoarthritis, and neuromuscular disorders. We presently investigated the association of quadriceps muscle fat with isometric strength measurements in healthy males using chemical shift encoding-based water-fat magnetic resonance imaging. Intermuscular adipose tissue fraction and intramuscular proton density fat fraction correlated significantly (P < 0.05) with isometric strength (up to r = −0.83 and −0.87, respectively). Reproducibility of intermuscular adipose tissue fraction and intramuscular proton density fat fraction was 1.5% and 5.7%, respectively. PMID:26953765

  18. Age-associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life

    PubMed Central

    Trombetti, A.; Reid, K. F.; Hars, M.; Herrmann, F. R.; Pasha, E.; Phillips, E. M.; Fielding, R. A.

    2016-01-01

    Summary This 3-year longitudinal study among older adults showed that declining muscle mass, strength, power, and physical performance are independent contributing factors to increased fear of falling, while declines of muscle mass and physical performance contribute to deterioration of quality of life. Our findings reinforce the importance of preserving muscle health with advancing age. Introduction The age-associated loss of skeletal muscle quantity and function are critical determinants of independent physical functioning in later life. Longitudinal studies investigating how decrements in muscle components of sarcopenia impact fear of falling (FoF) and quality of life (QoL) in older adults are lacking. Methods Twenty-six healthy older subjects (age, 74.1±3.7; Short Physical Performance Battery (SPPB) score ≥10) and 22 mobility-limited older subjects (age, 77.2±4.4; SPPB score ≥9) underwent evaluations of lower extremity muscle size and composition by computed tomography, strength and power, and physical performance at baseline and after 3-year follow-up. The Falls Efficacy Scale (FES) and Short Form-36 questionnaire (SF-36) were also administered at both timepoints to assess FoF and QoL, respectively. Results At 3-year follow-up, muscle cross-sectional area (CSA) (p<0.013) and power decreased (p<0.001), while intermuscular fat infiltration increased (p<0.001). These decrements were accompanied with a longer time to complete 400 m by 22±46 s (p<0.002). Using linear mixed-effects regression models, declines of muscle CSA, strength and power, and SPPB score were associated with increased FES score (p<0.05 for each model). Reduced physical component summary score of SF-36 over follow-up was independently associated with decreased SPPB score (p<0.020), muscle CSA (p<0.046), and increased 400 m walk time (p<0.003). Conclusions In older adults with and without mobility limitations, declining muscle mass, strength, power, and physical performance contribute

  19. High ionic strength and low pH detain activated skinned rabbit skeletal muscle crossbridges in a low force state.

    PubMed

    Seow, C Y; Ford, L E

    1993-04-01

    The effects of varying pH and ionic strength on the force-velocity relations and tension transients of skinned rabbit skeletal muscle were studied at 1-2 degrees C. Both decreasing pH from 7.35 to 6.35 and raising ionic strength from 125 to 360 mM reduced isometric force by about half and decreased sarcomere stiffness by about one-fourth, so that the stiffness/force ratio was increased by half. Lowering pH also decreased maximum shortening velocity by approximately 29%, while increasing ionic strength had little effect on velocity. These effects on velocity were correlated with asymmetrical effects on stiffness. The increase in the stiffness/force ratio with both interventions was manifest as a greater relative force change associated with a sarcomere length step. This force difference persisted for a variable time after the step. At the high ionic strength the force difference was long-lasting after stretches but relaxed quickly after releases, suggesting that the structures responsible would not impose much resistance to steady-state shortening. The opposite was found in the low pH experiments. The force difference relaxed quickly after stretches but persisted for a long time after releases. Furthermore, this force difference reached a constant value of approximately 8% of isometric force with intermediate sizes of release, and was not increased with larger releases. This value was almost identical to the value of an internal load that would be sufficient to account for the reduction in maximum velocity seen at the low pH. The results are interpreted as showing that both low pH and high ionic strength inhibit the movement of crossbridges into the force-generating parts of their cycle after they have attached to the actin filaments, with very few other effects on the cycle. The two interventions are different, however, in that detained bridges can be detached readily by shortening when the detention is caused by high ionic strength but not when it is caused by low

  20. Effects of Five-Week Resistance Training in Hypoxia on Hormones and Muscle Strength.

    PubMed

    Yan, Bing; Lai, Xiangxun; Yi, Longyan; Wang, Yang; Hu, Yang

    2016-01-01

    The effects of different levels of systemic hypoxia on hormonal responses, strength, and body composition to 5-week resistance training were investigated. Twenty-five male subjects were randomly assigned into 3 experimental groups that performed 10 sessions (2 sessions per week) of barbell back squat (10 repetitions, 5 sets, 70% 1 repetition maximum [RM]) under normoxia (NR, FiO2 = 21%) and hypoxia (HL, FiO2 = 16%; HH, FiO2 = 12.6%). Serum growth hormone (GH), testosterone (T), and cortisol (C) concentrations were measured before (Pre) and at 0 (T-0), 15 (T-15), 30 (T-30) minutes after exercise in the first and last training sessions. One repetition maximum, isometric knee extension, isometric leg press (LP), and body composition were evaluated before and after the protocol. In the first session, GH of HH (p < 0.01) and HL (p < 0.01) was higher than NR at T-0. In the last session, only GH of HH was higher than NR at T-0 (p ≤ 0.05); meanwhile, T/C ratio of HH was higher than NR at Pre (p < 0.01), T-0 (p < 0.01), and T-15 (p ≤ 0.05). Following the training protocol, HH showed greater (p ≤ 0.05) improvement of isometric LP strength compared with NR; lean body mass was increased in the hypoxia groups only. Moderate-intensity resistance training performed in severe hypoxia (FiO2 = 12.6%) induced greater GH responses and isometric strength gains in LP than that in NR. FiO2 of 12.6% was recommended when performing the moderate-intensity resistance training under systemic hypoxia. PMID:26691409

  1. Effect of Tai-chi exercise on lower limb muscle strength, bone mineral density and balance function of elderly women

    PubMed Central

    Song, Qing-Hua; Zhang, Quan-Hai; Xu, Rong-Mei; Ma, Ming; Zhao, Xin-Ping; Shen, Guo-Qing; Guo, Yan-Hua; Wang, Yi

    2014-01-01

    Abstract: To study the effect of Tai-chi exercise on lower limb muscle strength, bone mineral density and balance function of elderly female, 105 urban elderly women, who do insufficient exercise in daily life, are selected as the subject and randomly divided into an observation group (Tai Chi Group), a control group I (Dance Group) and a control group II (Walking Group). Each group is consists of 35 women. Among them, the women in the observation group do Tai-chi exercise once a day, while the women in the control group I dance once a day and in the control group II stick to brisk walking once a day. All women in the three groups do the above said exercises for 40 minutes and the exercise intensity is controlled to be medium. At the time of selection and after 4, 8 and 12 months upon their exercises, respectively detect and compare the lower limb skeletal muscle mass, lower limb muscle strength, bone mineral density and balance function of the subject. Results: At the time of selection, the general information of the subjects in the three groups show no significant difference (P > 0.05); however, after 4 months’ exercise, most of the study indexes in the control group I and group II are improved significantly (P < 0.05), while most of the study indexes in the observation group show no significant difference (P > 0.05) in comparison with those at the time of selection and their general improvement effect is slightly lower than that in the control group; after 8 months, relevant study indexes of the subjects in the three groups are significantly improved (P < 0.05) in comparison with those at the time of selection, especially, the effect in the observation group is more obvious and is better than that of the control group II (P < 0.05). 12 months later, the effect of the observation group is improved significantly from day to day when comparing to theose in the control group I and group II (P < 0.05 or P < 0.01). Conclusion: Compared with the senile dance and

  2. COMPARATIVE ANALYSIS ON MUSCLE STRENGTH AMONG PATIENTS WHO UNDERWENT ARTHROSCOPIC TENOTOMY OF THE LONG HEAD OF THE BICEPS IN RELATION TO ESTHETIC DEFORMITY

    PubMed Central

    Almeida, Alexandre; Valin, Márcio Rangel; de Almeida, Nayvaldo Couto; Roveda, Gilberto; Agostini, Ana Paula

    2015-01-01

    Objective: To determine whether there was any discrepancy in elbow flexion strength among patients with and without evident clinical deformity resulting from arthroscopic tenotomy on the long head of the biceps. Method: A group of 120 patients who underwent this procedure were evaluated. After applying the exclusion criteria, 89 patients remained in the analysis. Eighteen months after the operation (median), the elbow flexion strength was measured in newtons using a digital dynamometer. Three consecutive measurements were made and the average was used. The dominant and non-dominant sides were compared. Sex, age and mean elbow flexion strength in the operated and contralateral arms of patients with and without apparent clinical deformity were evaluated. Results: The median elbow flexion strength among the patients with evident clinical deformity was 17.78 N for the dominant arm and 20.87 N for the non-dominant arm. The difference was 2.51 N. In the group without evident clinical deformity, the difference was 2.14 N. The median muscle strength in the operated arm was 17.26 N, while the median was 20.06 N in the non-operated arm, thus suggesting that there was a significant loss of muscle strength (p = 0.005). The difference in muscle strength loss between the patients with and without evident deformity was not considered statistically significant (p = 0.977). Conclusion: The patients who underwent arthroscopic tenotomy on the long head of the biceps with or without apparent clinical deformity from distal migration presented similar elbow flexion muscle strength. PMID:27047871

  3. Resistance training and timed essential amino acids protect against the loss of muscle mass and strength during 28 days of bed rest and energy deficit

    PubMed Central

    Brooks, Naomi; Cloutier, Gregory J.; Cadena, Samuel M.; Layne, Jennifer E.; Nelsen, Carol A.; Freed, Alicia M.; Roubenoff, Ronenn; Castaneda-Sceppa, Carmen

    2008-01-01

    Spaceflight and bed rest (BR) result in losses of muscle mass and strength. Resistance training (RT) and amino acid (AA) supplementation are potential countermeasures to minimize these losses. However, it is unknown if timing of supplementation with exercise can optimize benefits, particularly with energy deficit. We examined the effect of these countermeasures on body composition, strength, and insulin levels in 31 men (ages 31–55 yr) during BR (28 days) followed by active recovery (14 days). Subjects were randomly assigned to essential AA supplementation (AA group, n = 7); RT with AA given 3 h after training (RT group, n = 12); or RT with AA given 5 min before training (AART group, n = 12). Energy intake was reduced by 8 ± 6%. Midthigh muscle area declined with BR for the AA > RT > AART groups: −11%, −3%, −4% (P = 0.05). Similarly, greatest losses in lower body muscle strength were seen in the AA group (−22%). These were attenuated in the exercising groups [RT (−8%) and AART (−6%; P < 0.05)]. Fat mass and midthigh intramuscular fat increased after BR in the AA group (+3% and +14%, respectively), and decreased in the RT (−5% and −4%) and AART groups (−1 and −5%; P = 0.05). Muscle mass and strength returned toward baseline after recovery, but the AA group showed the lowest regains. Combined resistance training with AA supplementation pre- or postexercise attenuated the losses in muscle mass and strength by approximately two-thirds compared with AA supplement alone during BR and energy deficit. These data support the efficacy of combined AA and RT as a countermeasure against muscle wasting due to low gravity. PMID:18483167

  4. Low level laser therapy associated with a strength training program on muscle performance in elderly women: a randomized double blind control study.

    PubMed

    Toma, Renata Luri; Vassão, Patrícia Gabrielli; Assis, Livia; Antunes, Hanna Karen Moreira; Renno, Ana Claudia Muniz

    2016-08-01

    The aging process leads to a gradual loss of muscle mass and muscle performance, leading to a higher functional dependence. Within this context, many studies have demonstrated the benefits of a combination of physical exercise and low level laser therapy (LLLT) as an intervention that enhances muscle performance in young people and athletes. The aim of this study was to evaluate the effects of combination of LLLT and strength training on muscle performance in elderly women. For this, a hundred elderly women were screened, and 48 met all inclusion criteria to participate in this double-blind placebo-controlled trial. Volunteers were divided in three groups: control (CG = 15), strength training associated with placebo LLLT (TG = 17), and strength training associated with active LLLT (808 nm, 100 mW, 7 J) (TLG = 16). The strength training consisted of knee flexion-extension performed with 80 % of 1-repetition maximum (1-RM) during 8 weeks. Several outcomes related to muscle performance were analyzed through the 6-min walk test (6-MWT), isokinetic dynamometry, surface electromyography (SEMG), lactate concentration, and 1-RM. The results revealed that a higher work (p = 0.0162), peak torque (p = 0.0309), and power (p = 0.0223) were observed in TLG compared to CG. Furthermore, both trained groups increased the 1-RM load (TG vs CG: p = 0.0067 and TLG vs CG: p < 0.0001) and decreased the lactate concentration in the third minute after isokinetic protocol (CG vs TLG: p = 0.0289 and CG vs TG: p = 0.0085). No difference in 6-MWT and in fatigue levels were observed among the groups. The present findings suggested that LLLT in combination with strength training was able to improve muscle performance in elderly people. PMID:27250715

  5. Intrarater reliabilities of shoulder joint horizontal adductor muscle strength measurements using a handheld dynamometer for geriatric and stroke patients

    PubMed Central

    Hirano, Masahiro; Katoh, Munenori; Kawaguchi, Saori; Uemura, Tomomi

    2016-01-01

    [Purpose] This study aimed to verify the appropriate number of measurements and the intrarater reliabilities of shoulder joint horizontal adductor muscle strength measurements using a handheld dynamometer (HHD) for geriatric and stroke patients. [Subjects and Methods] The subjects were 40 inpatients, who were divided into two groups: 20 stroke patients in the stroke group (SG), and 20 geriatric patients in the no-stroke group (N-SG). Measurements were performed three times using an HHD with a belt. The reliability was verified using Bland-Altman analysis and the intraclass correlation coefficient (ICC). [Results] ICC (1, 1) was >0.9. A systematic bias was not observed between the first and second measurement values except for the right side in N-SG. A systematic bias between the maximum value obtained during the first and second measurements and third measurement value was observed on the left side in N-SG, and on the non-paralyzed side in SG: the third measurement values were small in both cases. [Conclusion] Intrarater reliabilities were high for shoulder horizontal adductor strength measurements using an HHD with a belt for geriatric and stroke patients. Taking the systematic bias into consideration, these findings suggest that the required number of measurements is two. PMID:26957727

  6. Age-associated differences in triceps surae muscle composition and strength – an MRI-based cross-sectional comparison of contractile, adipose and connective tissue

    PubMed Central

    2014-01-01

    Background In human skeletal muscles, the aging process causes a decrease of contractile and a concomitant increase of intramuscular adipose (IMAT) and connective (IMCT) tissues. The accumulation of non-contractile tissues may contribute to the significant loss of intrinsic muscle strength typically observed at older age but their in vivo quantification is challenging. The purpose of this study was to establish MR imaging-based methods to quantify the relative amounts of IMCT, IMAT and contractile tissues in young and older human cohorts, and investigate their roles in determining age-associated changes in skeletal muscle strength. Methods Five young (31.6 ± 7.0 yrs) and five older (83.4 ± 3.2 yrs) Japanese women were subject to a detailed MR imaging protocol, including Fast Gradient Echo, Quantitative Fat/Water (IDEAL) and Ultra-short Echo Time (UTE) sequences, to determine contractile muscle tissue and IMAT within the entire Triceps Surae complex, and IMCT within both heads of the Gastrocnemius muscle. Specific force was calculated as the ratio of isometric plantarflexor force and the physiological cross-sectional area of the Triceps Surae complex. Results In the older cohort, total Triceps Surae volume was smaller by 17.5%, while the relative amounts of Triceps Surae IMAT and Gastrocnemius IMCT were larger by 55.1% and 48.9%, respectively. Differences of 38.6% and 42.1% in plantarflexor force and specific force were observed. After subtraction of IMAT and IMCT from total muscle volume, differences in intrinsic strength decreased to 29.6%. Conclusions Our data establishes that aging causes significant changes in skeletal muscle composition, with marked increases in non-contractile tissues. Such quantification of the remodeling process is likely to be of functional and clinical importance in elucidating the causes of the disproportionate age-associated decrease of force compared to that of muscle volume. PMID:24939372

  7. Bone density in young women is associated with body weight and muscle strength but not dietary intakes.

    PubMed

    Henderson, N K; Price, R I; Cole, J H; Gutteridge, D H; Bhagat, C I

    1995-03-01

    Potential determinants of bone mineral density (BMD) were studied cross-sectionally in 115 healthy, sexually mature Caucasian women aged 18 years. Bone mineral density (Hologic QDR1000W) of the lumbar spine, proximal femur (five sites), and distal tibia and fibula; fasting blood and urine calcium biochemistry; serum sex hormone levels (follicular phase); nutrient intakes; aerobic fitness; trunk muscle strength; and habitual activity levels were measured. The effects of heredity were considered by measuring the BMD of 107 of the subjects' mothers. Simple and stepwise regression analysis were used to identify significant determinants of BMD at each of the regions studied. The analysis indicated that significant bivariate correlations exist between BMD at all sites and body weight (r = 0.23-0.47, p < or = 0.01), lean body weight (r = 0.34-0.46), trunk strength (r = 0.27-0.47), physical activity score (r = 0.20-0.25), and aerobic fitness (r = 0.29-0.45). Dietary calcium intake correlated significantly with BMD at the trochanter site only (r = 0.19), and none of the biochemical or hormonal indices measured correlated consistently with BMD at any site. Significant correlations between the BMD of mothers and daughters ranged from r = 0.43 at lumbar spine to r = 0.34 at the intertrochanteric site. Paired t-tests showed the daughters had significantly (p < 0.03) lower BMD than their mothers at the lumbar spine (98 +/- 12% [mean +/- SD]) and significantly higher (p < 0.002) BMD at the femoral neck, trochanter, and total hip sites (110 +/- 16%, 108 +/- 17%, 103 +/- 14%, respectively). When stepwise regression analysis included weight-corrected strength of the trunk flexor muscles (Corr Flex), weight-corrected aerobic fitness (Corr VO2max), physical activity score, and body weight, body weight was the only significant determinant of BMD at all sites. Corr Flex made significant contributions at all sites except the femoral neck, while Corr VO2max made additional contribution at

  8. Short-Term Unilateral Resistance Training Results in Cross Education of Strength Without Changes in Muscle Size, Activation, or Endocrine Response.

    PubMed

    Beyer, Kyle S; Fukuda, David H; Boone, Carleigh H; Wells, Adam J; Townsend, Jeremy R; Jajtner, Adam R; Gonzalez, Adam M; Fragala, Maren S; Hoffman, Jay R; Stout, Jeffrey R

    2016-05-01

    Beyer, KS, Fukuda, DH, Boone, CH, Wells, AJ, Townsend, JR, Jajtner, AR, Gonzalez, AM, Fragala, MS, Hoffman, JR, and Stout, JR. Short-term unilateral resistance training results in cross education of strength without changes in muscle size, activation, or endocrine response. J Strength Cond Res 30(5): 1213-1223, 2016-The purpose of this study was to assess the cross education of strength and changes in the underlying mechanisms (muscle size, activation, and hormonal response) after a 4-week unilateral resistance training (URT) program. A group of 9 untrained men completed a 4-week URT program on the dominant leg (DOM), whereas cross education was measured in the nondominant leg (NON); and were compared with a control group (n = 8, CON). Unilateral isometric force (PKF), leg press (LP) and leg extension (LE) strength, muscle size (by ultrasonography) and activation (by electromyography) of the rectus femoris and vastus lateralis, and the hormonal response (testosterone, growth hormone, insulin, and insulin-like growth factor-1) were tested pretraining and posttraining. Group × time interactions were present for PKF, LP, LE, and muscle size in DOM and for LP in NON. In all interactions, the URT group improved significantly better than CON. There was a significant acute hormonal response to URT, but no chronic adaptation after the 4-week training program. Four weeks of URT resulted in an increase in strength and size of the trained musculature, and cross education of strength in the untrained musculature, which may occur without detectable changes in muscle size, activation, or the acute hormonal response. PMID:26466136

  9. Caffeine-induced increase in voluntary activation and strength of the quadriceps muscle during isometric, concentric and eccentric contractions

    PubMed Central

    Behrens, Martin; Mau-Moeller, Anett; Weippert, Matthias; Fuhrmann, Josefin; Wegner, Katharina; Skripitz, Ralf; Bader, Rainer; Bruhn, Sven

    2015-01-01

    This study investigated effects of caffeine ingestion (8 mg/kg) on maximum voluntary torque (MVT) and voluntary activation of the quadriceps during isometric, concentric and eccentric contractions. Fourteen subjects ingested caffeine and placebo in a randomized, controlled, counterbalanced, double-blind crossover design. Neuromuscular tests were performed before and 1 h after oral caffeine and placebo intake. MVTs were measured and the interpolated twitch technique was applied during isometric, concentric and eccentric contractions to assess voluntary activation. Furthermore, normalized root mean square of the EMG signal was calculated and evoked spinal reflex responses (H-reflex evoked at rest and during weak isometric voluntary contraction) as well as twitch torques were analyzed. Caffeine increased MVT by 26.4 N m (95%CI: 9.3-43.5 N m, P = 0.004), 22.5 N m (95%CI: 3.1-42.0 N m, P = 0.025) and 22.5 N m (95%CI: 2.2-42.7 N m, P = 0.032) for isometric, concentric and eccentric contractions. Strength enhancements were associated with increases in voluntary activation. Explosive voluntary strength and voluntary activation at the onset of contraction were significantly increased following caffeine ingestion. Changes in spinal reflex responses and at the muscle level were not observed. Data suggest that caffeine ingestion induced an acute increase in voluntary activation that was responsible for the increased strength regardless of the contraction mode. PMID:25969895

  10. Gap junctions and inhibitory synapses modulate inspiratory motoneuron synchronization.

    PubMed

    Bou-Flores, C; Berger, A J

    2001-04-01

    Interneuronal electrical coupling via gap junctions and chemical synaptic inhibitory transmission are known to have roles in the generation and synchronization of activity in neuronal networks. Uncertainty exists regarding the roles of these two modes of interneuronal communication in the central respiratory rhythm-generating system. To assess their roles, we performed studies on both the neonatal mouse medullary slice and en bloc brain stem-spinal cord preparations where rhythmic inspiratory motor activity can readily be recorded from both hypoglossal and phrenic nerve roots. The rhythmic inspiratory activity observed had two temporal characteristics: the basic respiratory frequency occurring on a long time scale and the synchronous neuronal discharge within the inspiratory burst occurring on a short time scale. In both preparations, we observed that bath application of gap-junction blockers, including 18 alpha-glycyrrhetinic acid, 18 beta-glycyrrhetinic acid, and carbenoxolone, all caused a reduction in respiratory frequency. In contrast, peak integrated phrenic and hypoglossal inspiratory activity was not significantly changed by gap-junction blockade. On a short-time-scale, gap-junction blockade increased the degree of synchronization within an inspiratory burst observed in both nerves. In contrast, opposite results were observed with blockade of GABA(A) and glycine receptors. We found that respiratory frequency increased with receptor blockade, and simultaneous blockade of both receptors consistently resulted in a reduction in short-time-scale synchronized activity observed in phrenic and hypoglossal inspiratory bursts. These results support the concept that the central respiratory system has two components: a rhythm generator responsible for the production of respiratory cycle timing and an inspiratory pattern generator that is involved in short-time-scale synchronization. In the neonatal rodent, properties of both components can be regulated by interneuronal

  11. The Lack of CuZnSOD Leads to Impaired Neurotransmitter Release, Neuromuscular Junction Destabilization and Reduced Muscle Strength in Mice

    PubMed Central

    Walsh, Michael E.; Liu, Yuhong; Zhang, Yiqiang; Jaramillo, Carlos A.; Macleod, Gregory T.; Van Remmen, Holly

    2014-01-01

    Elevated reactive oxygen species (ROS) production and ROS-dependent protein damage is a common observation in the pathogenesis of many muscle wasting disorders, including sarcopenia. However, the contribution of elevated ROS levels to –a breakdown in neuromuscular communication and muscle atrophy remains unknown. In this study, we examined a copper zinc superoxide dismutase [CuZnSOD (Sod1)] knockout mouse (Sod1−/−), a mouse model of elevated oxidative stress that exhibits accelerated loss of muscle mass, which recapitulates many phenotypes of sarcopenia as early as 5 months of age. We found that young adult Sod1−/− mice display a considerable reduction in hind limb skeletal muscle mass and strength when compared to age-matched wild-type mice. These changes are accompanied by gross alterations in neuromuscular junction (NMJ) morphology, including reduced occupancy of the motor endplates by axons, terminal sprouting and axon thinning and irregular swelling. Surprisingly however, the average density of acetylcholine receptors in endplates is preserved. Using in vivo electromyography and ex vivo electrophysiological studies of hind limb muscles in Sod1−/− mice, we found that motor axons innervating the extensor digitorum longus (EDL) and gastrocnemius muscles release fewer synaptic vesicles upon nerve stimulation. Recordings from individually identified EDL NMJs show that reductions in neurotransmitter release are apparent in the Sod1−/− mice even when endplates are close to fully innervated. However, electrophysiological properties, such as input resistance, resting membrane potential and spontaneous neurotransmitter release kinetics (but not frequency) are similar between EDL muscles of Sod1−/− and wild-type mice. Administration of the potassium channel blocker 3,4-diaminopyridine, which broadens the presynaptic action potential, improves both neurotransmitter release and muscle strength. Together, these results suggest that ROS-associated motor

  12. Effect of previous strength training episode and retraining on facilitation of skeletal muscle hypertrophy and contractile properties after long-term detraining in rats

    PubMed Central

    Lee, Sukho; Hong, Kwang-Seok; Kim, Kijeong

    2016-01-01

    In the present study, we investigated the effects of previous strength training and retraining following long-term cessation of exercise on muscle mass and contractile properties. Female Sprague-Dawley rats (n=24) aged eight weeks were randomly assigned one of the four groups: control (CON), detraining (DT), training (TR), and retraining (RT). The training regimen consisted of climbing ladder 5×3 sets, once every third day for eight weeks with weight attached to the tail. The weight carried during each training session was initially 50% of body weight and progressively increased by 10% per session. The rats in DT were detained for 20 weeks followed by eight weeks strength training. The rats in the both TR and RT groups underwent eight weeks training. DT was age matched new training group while RT was retraining group after 20 weeks of detraining. Soleus, gastrocnemius, tibialis anterior, and flexor hallucis longus (FHL) muscles were harvested in order to measure the weight, and in situ contractile properties of FHL were measured including specific twitch tension (Spt) and specific tetanic tension (Spo). TR showed significant increase in muscle mass compared to CON (P<0.05). DT and RT showed significant increase in muscle mass when compared to all other groups (P<0.05). There was no statistical difference in Spt and Spo among the groups. The present study showed that previous strength training facilitates retraining-induced muscle hypertrophy following long-term cessation of exercise. PMID:27162768

  13. Effect of previous strength training episode and retraining on facilitation of skeletal muscle hypertrophy and contractile properties after long-term detraining in rats.

    PubMed

    Lee, Sukho; Hong, Kwang-Seok; Kim, Kijeong

    2016-04-01

    In the present study, we investigated the effects of previous strength training and retraining following long-term cessation of exercise on muscle mass and contractile properties. Female Sprague-Dawley rats (n=24) aged eight weeks were randomly assigned one of the four groups: control (CON), detraining (DT), training (TR), and retraining (RT). The training regimen consisted of climbing ladder 5×3 sets, once every third day for eight weeks with weight attached to the tail. The weight carried during each training session was initially 50% of body weight and progressively increased by 10% per session. The rats in DT were detained for 20 weeks followed by eight weeks strength training. The rats in the both TR and RT groups underwent eight weeks training. DT was age matched new training group while RT was retraining group after 20 weeks of detraining. Soleus, gastrocnemius, tibialis anterior, and flexor hallucis longus (FHL) muscles were harvested in order to measure the weight, and in situ contractile properties of FHL were measured including specific twitch tension (Spt) and specific tetanic tension (Spo). TR showed significant increase in muscle mass compared to CON (P<0.05). DT and RT showed significant increase in muscle mass when compared to all other groups (P<0.05). There was no statistical difference in Spt and Spo among the groups. The present study showed that previous strength training facilitates retraining-induced muscle hypertrophy following long-term cessation of exercise. PMID:27162768

  14. Efficacy of kinesio tape application on pain and muscle strength in patients with myofascial pain syndrome: a placebo-controlled trial

    PubMed Central

    Öztürk, Gülcan; Külcü, Duygu Geler; Mesci, Nilgün; Şilte, Ayşe Duygu; Aydog, Ece

    2016-01-01

    [Purpose] The purpose of this study was to determine the short- and mid-term effects of Kinesio taping on the trapezius muscle in individuals with myofascial pain syndrome. [Subjects and Methods] Thirty-seven patients with active upper trapezius myofascial trigger points were randomly divided to 2 groups: group 1 received Kinesio taping for the upper trapezius muscle, and group 2 received a sham Kinesio taping application. Neck pain (Visual Analog Scale and pressure algometry) and trapezius muscle strength data were collected at baseline, immediately after Kinesio taping application, and at one month follow-up. [Results] The mean changes in Visual Analog Scale scores were significantly different between groups at T2 and T1, with less pain in group 1. The mean changes in algometry scores were significantly different between groups at T3 compared with T2 in favor of group 1. The mean changes in trapezius muscle strength were significantly different between the groups at T2 compared with T1 in favor of group 1. [Conclusion] Patients with myofascial pain syndrome receiving an application of Kinesio taping exhibited statistically significant improvements in pain and upper trapezius muscle strength. PMID:27190430

  15. Efficacy of kinesio tape application on pain and muscle strength in patients with myofascial pain syndrome: a placebo-controlled trial.

    PubMed

    Öztürk, Gülcan; Külcü, Duygu Geler; Mesci, Nilgün; Şilte, Ayşe Duygu; Aydog, Ece

    2016-04-01

    [Purpose] The purpose of this study was to determine the short- and mid-term effects of Kinesio taping on the trapezius muscle in individuals with myofascial pain syndrome. [Subjects and Methods] Thirty-seven patients with active upper trapezius myofascial trigger points were randomly divided to 2 groups: group 1 received Kinesio taping for the upper trapezius muscle, and group 2 received a sham Kinesio taping application. Neck pain (Visual Analog Scale and pressure algometry) and trapezius muscle strength data were collected at baseline, immediately after Kinesio taping application, and at one month follow-up. [Results] The mean changes in Visual Analog Scale scores were significantly different between groups at T2 and T1, with less pain in group 1. The mean changes in algometry scores were significantly different between groups at T3 compared with T2 in favor of group 1. The mean changes in trapezius muscle strength were significantly different between the groups at T2 compared with T1 in favor of group 1. [Conclusion] Patients with myofascial pain syndrome receiving an application of Kinesio taping exhibited statistically significant improvements in pain and upper trapezius muscle strength. PMID:27190430

  16. Resistance training and timed essential amino acids protect against the loss of muscle mass and strength during 28 days of bed rest and energy deficit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Space flight and bed rest (BR) result in losses of muscle mass and strength. Resistance training (RT) and amino acid (AA) supplementation are potential countermeasures to minimize these losses. However, it is unknown if timing of supplementation with exercise can optimize benefits, particularly with...

  17. Efficacy of whey protein supplementation on resistance exercise-induced changes in muscle strength, lean mass, and function in mobility-limited older adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whey protein supplementation may augment resistance exercise-induced increases in muscle strength and mass. Further studies are required to determine whether this effect extends to functionally compromised older adults. The objectives of the study were to compare the effects of whey protein concent...

  18. Influence of body composition, muscle strength, diet and physical activity on total body and forearm bone mass in Chinese adolescent girls.

    PubMed

    Foo, Leng Huat; Zhang, Qian; Zhu, Kun; Ma, Guansheng; Greenfield, Heather; Fraser, David R

    2007-12-01

    The aim of the present study was to determine association between body composition, muscle strength, diet and physical exercise with bone mineral content (BMC) and bone area (BA) in 283 Chinese adolescent girls aged 15 years in Beijing, China. Body composition, pubertal stage, physical activity and dietary intakes were assessed using standard validated protocols. Total body and forearm bone, lean body mass (LBM) and fat body mass (FBM) were determined by dual X-ray absorptiometry. Multivariate linear regression analyses were carried out to examine the predictors of BMC and BA, after controlling for potential confounders. The subjects had a mean age of 15.0 (sd 0.9) years and 99.6 % of them had reached menarche. Multivariate analyses showed that LBM, FBM, handgrip muscle strength and milk intake were significant independent determinants of BMC and BA of the total body and/or forearm sites. LBM was found to be a stronger independent determinant than FBM of BMC and BA, whereas handgrip muscle strength was only found as significant determinant of BMC and BA at the forearm sites than in total body BMC and BA. Further, total physical activity level had a significant positive association with handgrip and LBM. This suggested that greater muscle strength and higher LBM may reflect higher levels of physical activity. Therefore, continuous healthy lifestyle practices such as adequate intake of milk and continuous participation in physical activity should be encouraged throughout adolescence to optimise bone growth during this period. PMID:17640423

  19. Effects of combined open kinetic chain and closed kinetic chain training using pulley exercise machines on muscle strength and angiogenesis factors

    PubMed Central

    Jang, Ki Soeng; Kang, Sunghwun; Woo, Sang Heon; Bae, Ju Yong; Shin, Ki Ok

    2016-01-01

    [Purpose] This study investigated the effects of combined open kinetic chain and closed kinetic chain training using pulley exercise machines on muscle strength, anaerobic power, and blood levels of angiogenesis factors. [Subjects and Methods] Twenty male university students were equally divided between control and pulley training groups. The pulley-training group underwent 8 weeks of combined training. Open kinetic chain training consisted of 2 sets of 10 repetitions at 60% of one repetition maximum; closed kinetic chain training consisted of 2 sets of 10 repetitions of resistance exercise using the subject’s own body weight. Isokinetic strength (trunk and knee), anaerobic power, vascular endothelial growth factor, angiopoietin-1, angiopoietin-2, and follistatin were analyzed. [Results] After 8 weeks, flexor and extensor muscle strength significantly increased in the trunk and knee; average and peak power also increased significantly. Angiopoietin 1 increased 25% in the control group and 48% in the pulley training group; vascular endothelial growth factor and follistatin increased significantly in the pulley-training group after 8 weeks. [Conclusion] Eight weeks of combined training using pulley exercise machines effectively increased biochemical factors related to muscle growth, as well as muscle strength in the trunk and knees. PMID:27134393

  20. Differential Effect of Taekwondo Training on Knee Muscle Strength and Reactive and Static Balance Control in Children with Developmental Coordination Disorder: A Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Fong, Shirley S. M.; Chung, Joanne W. Y.; Chow, Lina P. Y.; Ma, Ada W. W.; Tsang, William W. N.

    2013-01-01

    This randomized controlled trial aimed to investigate the effect of short-term intensive TKD training on the isokinetic knee muscle strength and reactive and static balance control of children with developmental coordination disorder (DCD). Among the 44 children with DCD (mean age: 7.6 plus or minus 1.3 years) recruited, 21 were randomly assigned…

  1. Muscle strength and BMI as predictors of major mobility disability in the lifestyle interventions and independence for elders pilot (LIFE-P)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Muscle weakness and obesity are two significant threats to mobility facing the increasing number of older adults. To date, there are no studies that have examined the association of strength and body mass index (BMI) on event rates on a widely used performance measure of major mobility disability. T...

  2. Is quadriceps muscle strength a determinant of the physical function of the elderly?

    PubMed Central

    Altubasi, Ibrahim Mustafa

    2015-01-01

    [Purpose] To determine the relationships of the quadriceps rate of torque development and the time to peak torque with the physical function of the elderly. [Subjects and Methods] Twenty-one subjects participated in this study. Quadriceps strength was measured using isometric and isokinetic torque tests. Time to peak torque and rate of torque development were calculated from the torque time curve of the isokinetic and isometric torque tests, respectively. Physical activities were measured using 4 physical activity tests. Pearson correlation coefficients were used to examine the relationships among the variables. [Results] The time to peak torque showed significant correlations with all measures of physical activity tests. Rate of torque development showed significant correlation with the timed stair-climbing test. Isometric and isokinetic torques had no significant correlations with any of the physical activity tests. [Conclusion] Time to maximum torque and the rate of torque development might be more important than peak torque in determining the physical function of the elderly. PMID:26644638

  3. Implications of movement-related cortical potential for understanding neural adaptations in muscle strength tasks

    PubMed Central

    2014-01-01

    This systematic review aims to provide information about the implications of the movement-related cortical potential (MRCP) in acute and chronic responses to the counter resistance training. The structuring of the methods of this study followed the proposals of the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses). It was performed an electronically search in Pubmed/Medline and ISI Web of Knowledge data bases, from 1987 to 2013, besides the manual search in the selected references. The following terms were used: Bereitschaftspotential, MRCP, strength and force. The logical operator “AND” was used to combine descriptors and terms used to search publications. At the end, 11 studies attended all the eligibility criteria and the results demonstrated that the behavior of MRCP is altered because of different factors such as: force level, rate of force development, fatigue induced by exercise, and the specific phase of muscular action, leading to an increase in the amplitude in eccentric actions compared to concentric actions, in acute effects. The long-term adaptations demonstrated that the counter resistance training provokes an attenuation in the amplitude in areas related to the movement, which may be caused by neural adaptation occurred in the motor cortex. PMID:24602228

  4. Implications of movement-related cortical potential for understanding neural adaptations in muscle strength tasks.

    PubMed

    Lattari, Eduardo; Arias-Carrión, Oscar; Monteiro-Junior, Renato Sobral; Mello Portugal, Eduardo Matta; Paes, Flávia; Menéndez-González, Manuel; Silva, Adriana Cardoso; Nardi, Antonio Egidio; Machado, Sergio

    2014-01-01

    This systematic review aims to provide information about the implications of the movement-related cortical potential (MRCP) in acute and chronic responses to the counter resistance training. The structuring of the methods of this study followed the proposals of the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses). It was performed an electronically search in Pubmed/Medline and ISI Web of Knowledge data bases, from 1987 to 2013, besides the manual search in the selected references. The following terms were used: Bereitschaftspotential, MRCP, strength and force. The logical operator "AND" was used to combine descriptors and terms used to search publications. At the end, 11 studies attended all the eligibility criteria and the results demonstrated that the behavior of MRCP is altered because of different factors such as: force level, rate of force development, fatigue induced by exercise, and the specific phase of muscular action, leading to an increase in the amplitude in eccentric actions compared to concentric actions, in acute effects. The long-term adaptations demonstrated that the counter resistance training provokes an attenuation in the amplitude in areas related to the movement, which may be caused by neural adaptation occurred in the motor cortex. PMID:24602228

  5. Effects of diaphragmatic control on the assessment of sniff nasal inspiratory pressure and maximum relaxation rate

    PubMed Central

    Benício, Kadja; Dias, Fernando A. L.; Gualdi, Lucien P.; Aliverti, Andrea; Resqueti, Vanessa R.; Fregonezi, Guilherme A. F.

    2015-01-01

    OBJECTIVE: To assess the influence of diaphragmatic activation control (diaphC) on Sniff Nasal-Inspiratory Pressure (SNIP) and Maximum Relaxation Rate of inspiratory muscles (MRR) in healthy subjects. METHOD: Twenty subjects (9 male; age: 23 (SD=2.9) years; BMI: 23.8 (SD=3) kg/m2; FEV1/FVC: 0.9 (SD=0.1)] performed 5 sniff maneuvers in two different moments: with or without instruction on diaphC. Before the first maneuver, a brief explanation was given to the subjects on how to perform the sniff test. For sniff test with diaphC, subjects were instructed to perform intense diaphragm activation. The best SNIP and MRR values were used for analysis. MRR was calculated as the ratio of first derivative of pressure over time (dP/dtmax) and were normalized by dividing it by peak pressure (SNIP) from the same maneuver. RESULTS: SNIP values were significantly different in maneuvers with and without diaphC [without diaphC: -100 (SD=27.1) cmH2O/ with diaphC: -72.8 (SD=22.3) cmH2O; p<0.0001], normalized MRR values were not statistically different [without diaphC: -9.7 (SD=2.6); with diaphC: -8.9 (SD=1.5); p=0.19]. Without diaphC, 40% of the sample did not reach the appropriate sniff criteria found in the literature. CONCLUSION: Diaphragmatic control performed during SNIP test influences obtained inspiratory pressure, being lower when diaphC is performed. However, there was no influence on normalized MRR. PMID:26578254

  6. Daily Overfeeding from Protein and/or Carbohydrate Supplementation for Eight Weeks in Conjunction with Resistance Training Does not Improve Body Composition and Muscle Strength or Increase Markers Indicative of Muscle Protein Synthesis and Myogenesis in Resistance-Trained Males

    PubMed Central

    Spillane, Mike; Willoughby, Darryn S.

    2016-01-01

    This study determined the effects of heavy resistance training and daily overfeeding with carbohydrate and/or protein on blood and skeletal muscle markers of protein synthesis (MPS), myogenesis, body composition, and muscle performance. Twenty one resistance-trained males were randomly assigned to either a protein + carbohydrate [HPC (n = 11)] or a carbohydrate [HC (n = 10)] supplement group in a double-blind fashion. Body composition and muscle performance were assessed, and venous blood samples and muscle biopsies were obtained before and after eight weeks of resistance training and supplementation. Data were analyzed by two-way ANOVA (p ≤ 0.05). Total body mass, body water, and fat mass were significantly increased in both groups in response to resistance training, but not supplementation (p < 0.05); however, lean mass was not significantly increased in either group (p = 0.068). Upper- (p = 0.024) and lower-body (p = 0.001) muscle strength and myosin heavy chain (MHC) 1 (p = 0.039) and MHC 2A (p = 0.027) were also significantly increased with resistance training. Serum IGF-1, GH, and HGF were not significantly affected (p > 0.05). Muscle total DNA, total protein, and c-Met were not significantly affected (p > 0.05). In conjunction with resistance training, the peri-exercise and daily overfeeding of protein and/or carbohydrate did not preferentially improve body composition, muscle performance, and markers indicative of MPS and myogenic activation. Key points In response to 56 days of heavy resistance training and HC or HPC supplementation, similar increases in muscle mass and strength in both groups occurred; however, the increases were not different between supplement groups. The supplementation of HPC had no preferential effect on augmenting serum IGF-1 GH, or HGF. The supplementation of HPC had no preferential effect on augmenting increases in total muscle protein content or the myogenic markers, total DNA and muscle cMet content. In response to 56 days of

  7. Daily Overfeeding from Protein and/or Carbohydrate Supplementation for Eight Weeks in Conjunction with Resistance Training Does not Improve Body Composition and Muscle Strength or Increase Markers Indicative of Muscle Protein Synthesis and Myogenesis in Resistance-Trained Males.

    PubMed

    Spillane, Mike; Willoughby, Darryn S

    2016-03-01

    This study determined the effects of heavy resistance training and daily overfeeding with carbohydrate and/or protein on blood and skeletal muscle markers of protein synthesis (MPS), myogenesis, body composition, and muscle performance. Twenty one resistance-trained males were randomly assigned to either a protein + carbohydrate [HPC (n = 11)] or a carbohydrate [HC (n = 10)] supplement group in a double-blind fashion. Body composition and muscle performance were assessed, and venous blood samples and muscle biopsies were obtained before and after eight weeks of resistance training and supplementation. Data were analyzed by two-way ANOVA (p ≤ 0.05). Total body mass, body water, and fat mass were significantly increased in both groups in response to resistance training, but not supplementation (p < 0.05); however, lean mass was not significantly increased in either group (p = 0.068). Upper- (p = 0.024) and lower-body (p = 0.001) muscle strength and myosin heavy chain (MHC) 1 (p = 0.039) and MHC 2A (p = 0.027) were also significantly increased with resistance training. Serum IGF-1, GH, and HGF were not significantly affected (p > 0.05). Muscle total DNA, total protein, and c-Met were not significantly affected (p > 0.05). In conjunction with resistance training, the peri-exercise and daily overfeeding of protein and/or carbohydrate did not preferentially improve body composition, muscle performance, and markers indicative of MPS and myogenic activation. Key pointsIn response to 56 days of heavy resistance training and HC or HPC supplementation, similar increases in muscle mass and strength in both groups occurred; however, the increases were not different between supplement groups.The supplementation of HPC had no preferential effect on augmenting serum IGF-1 GH, or HGF.The supplementation of HPC had no preferential effect on augmenting increases in total muscle protein content or the myogenic markers, total DNA and muscle cMet content.In response to 56 days of a

  8. Interplay among the changes of muscle strength, cross-sectional area and maximal explosive power: theory and facts.

    PubMed

    Zamparo, P; Minetti, A E; di Prampero, P E

    2002-12-01

    A model has recently been proposed to predict the changes of mechanical power (W) during a maximal explosive effort (such as a standing high jump off both feet) following an adaptation (e.g. training/de-training). The model is based on the assumption that, all other things being equal (ceteris paribus), the predicted changes in W depend on the measured changes of muscle force (F) or cross-sectional area (CSA) only. It follows that, if the measured changes in W are not equal to those predicted by the model, factors other than a change in F (or CSA) must be responsible for this difference. The model does not allow the determination of factors specifically involved in the adaptation process but it helps in discriminating whether an adaptation has taken place at a local level (when the observed changes in F would be attributed to factors other than the observed changes in CSA, e.g. co-contractions, fibre type modifications...), or at a central level (when the observed changes in W would be attributed to other factors than the observed changes in F, e.g. co-ordination of multiple joints and muscle groups...), or in both regions. In this paper the model has been applied to data reported in the literature on disuse (BR, bed rest), de-conditioning (SF, space flight), strength training (ST) and de-training (DT). The results of these calculations have confirmed previous observations on the determinants of the adaptation process and further suggest: (1) that training for one specific motor task (e.g. ST) could affect the performance of a second task (e.g. a maximal explosive jump) but that, as soon as the trained motor task is terminated (DT), this ability is re-gained; and (2) that neuromuscular impairment in disuse (BR) is closer to de-training than to the de-conditioning brought about by weightlessness (SF). PMID:12458362

  9. The one repetition maximum test and the sit-to-stand test in the assessment of a specific pulmonary rehabilitation program on peripheral muscle strength in COPD patients

    PubMed Central

    Zanini, Andrea; Aiello, Marina; Cherubino, Francesca; Zampogna, Elisabetta; Azzola, Andrea; Chetta, Alfredo; Spanevello, Antonio

    2015-01-01

    Background Individuals with COPD may present reduced peripheral muscle strength, leading to impaired mobility. Comprehensive pulmonary rehabilitation (PR) should include strength training, in particular to lower limbs. Furthermore, simple tools for the assessment of peripheral muscle performance are required. Objectives To assess the peripheral muscle performance of COPD patients by the sit-to-stand test (STST), as compared to the one-repetition maximum (1-RM), considered as the gold standard for assessing muscle strength in non-laboratory situations, and to evaluate the responsiveness of STST to a PR program. Methods Sixty moderate-to-severe COPD inpatients were randomly included into either the specific strength training group or into the usual PR program group. Patients were assessed on a 30-second STST and 1-minute STST, 1-RM, and 6-minute walking test (6MWT), before and after PR. Bland–Altman plots were used to evaluate the agreement between 1-RM and STST. Results The two groups were not different at baseline. In all patients, 1-RM was significantly related to the 30-second STST (r=0.48, P<0.001) and to 1-minute STST (r=0.36, P=0.005). The 30-second STST was better tolerated in terms of the perceived fatigue (P=0.002) and less time consuming (P<0.001) test. In the specific strength training group significant improvements were observed in the 30-second STST (P<0.001), 1-minute STST (P=0.005), 1-RM (P<0.001), and in the 6MWT (P=0.001). In the usual PR program group, significant improvement was observed in the 30-second STST (P=0.042) and in the 6MWT (P=0.001). Conclusion Our study shows that in stable moderate-to-severe inpatients with COPD, STST is a valid and reliable tool to assess peripheral muscle performance of lower limbs, and is sensitive to a specific PR program. PMID:26648705

  10. Independent and Combined Association of Muscle Strength and Cardiorespiratory Fitness in Youth With Insulin Resistance and β-Cell Function in Young Adulthood

    PubMed Central

    Grøntved, Anders; Ried-Larsen, Mathias; Ekelund, Ulf; Froberg, Karsten; Brage, Søren; Andersen, Lars B.

    2013-01-01

    OBJECTIVE To examine the independent and combined association of isometric muscle strength of the abdomen and back and cardiorespiratory fitness (CRF) in youth with indices of glucose metabolism in young adulthood among boys and girls from the European Youth Heart Study. RESEARCH DESIGN AND METHODS We used data from a population-based prospective cohort study among youth followed up for up to 12 years (n = 317). In youth, maximal voluntary contractions during isometric back extension and abdominal flexion were determined using a strain-gauge dynamometer and CRF was obtained from a maximal cycle ergometer test. Insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR]) and β-cell function (homeostasis model assessment of β-cell function [HOMA-B]) were estimated from fasting serum insulin and glucose that were obtained in youth and at follow-up in young adulthood. RESULTS For each 1-SD difference in isometric muscle strength (0.16 N/kg) in youth, fasting insulin, HOMA-IR, and HOMA-B in young adulthood changed by −11.3% (95% CI −17.0 to −5.2), −12.2% (−18.2 to −5.7), and −8.9% (−14.4 to −3.0), respectively, in young adulthood after adjustment for CRF and personal lifestyle and demographic factors. Results for CRF were very similar in magnitude, and the magnitude of associations for both exposures was unchanged with additional adjustment for general or abdominal adiposity in youth. Combined associations of muscle strength and CRF with fasting insulin, HOMA-IR, and HOMA-B were additive, and adolescents in the highest sex-specific tertile for both isometric muscle strength and CRF had the lowest levels of these glucose metabolism outcomes. CONCLUSIONS Increasing muscle strength and CRF should be targets in youth primordial prevention strategies of insulin resistance and β-cell dysfunction. PMID:23579180

  11. Knee Muscles Isokinetic Evaluation after a Six-Month Regular Combined Swim and Dry-Land Strength Training Period in Adolescent Competitive Swimmers

    PubMed Central

    Dalamitros, Athanasios A.; Manou, Vasiliki; Christoulas, Kosmas; Kellis, Spiros

    2015-01-01

    Previous studies demonstrated significant increases in the shoulder internal rotators’ peak torque values and unilateral muscular imbalances of the shoulder rotators after a competitive swim period. However, there are no similar data concerning the knee muscles. The purpose of the current study was to examine the effects of a six-month training period on knee flexor and extensor peak torque values, examine a possible bilateral strength deficit and evaluate the unilateral strength balance in competitive swimmers. Eleven male adolescent swimmers (age: 14.82 ± 0.45 years) were tested for concentric knee extension and flexion peak torque (60°/s) with an isokinetic dynamometer, before and after a regular combined swim and dry-land strength training period. A trend towards greater improvements in the knee extensor compared to flexor muscles peak torque was observed. Furthermore, the bilateral strength deficit remained almost unchanged, whereas unilateral strength imbalance was increased for both limbs. However, all results were non-significant (p > 0.05). According to the data presented, a six-month regular combined swim and dry-land strength training period caused non-significant alterations for all the parameters evaluated during isokinetic testing. This study highlights the fact that competitive adolescent swimmers demonstrated unilateral knee strength imbalances throughout a long period of their yearly training macrocycle. PMID:26839619

  12. Knee Muscles Isokinetic Evaluation after a Six-Month Regular Combined Swim and Dry-Land Strength Training Period in Adolescent Competitive Swimmers.

    PubMed

    Dalamitros, Athanasios A; Manou, Vasiliki; Christoulas, Kosmas; Kellis, Spiros

    2015-12-22

    Previous studies demonstrated significant increases in the shoulder internal rotators' peak torque values and unilateral muscular imbalances of the shoulder rotators after a competitive swim period. However, there are no similar data concerning the knee muscles. The purpose of the current study was to examine the effects of a six-month training period on knee flexor and extensor peak torque values, examine a possible bilateral strength deficit and evaluate the unilateral strength balance in competitive swimmers. Eleven male adolescent swimmers (age: 14.82 ± 0.45 years) were tested for concentric knee extension and flexion peak torque (60°/s) with an isokinetic dynamometer, before and after a regular combined swim and dry-land strength training period. A trend towards greater improvements in the knee extensor compared to flexor muscles peak torque was observed. Furthermore, the bilateral strength deficit remained almost unchanged, whereas unilateral strength imbalance was increased for both limbs. However, all results were non-significant (p > 0.05). According to the data presented, a six-month regular combined swim and dry-land strength training period caused non-significant alterations for all the parameters evaluated during isokinetic testing. This study highlights the fact that competitive adolescent swimmers demonstrated unilateral knee strength imbalances throughout a long period of their yearly training macrocycle. PMID:26839619

  13. The effects of training by virtual reality or gym ball on pelvic floor muscle strength in postmenopausal women: a randomized controlled trial

    PubMed Central

    Martinho, Natalia M.; Silva, Valéria R.; Marques, Joseane; Carvalho, Leonardo C.; Iunes, Denise H.; Botelho, Simone

    2016-01-01

    ABSTRACT Objective To evaluate the effectiveness of abdominopelvic training by virtual reality compared to pelvic floor muscle training (PFMT) using a gym ball (a previously tested and efficient protocol) on postmenopausal women’s pelvic floor muscle (PFM) strength. Method A randomized controlled trial was conducted with 60 postmenopausal women, randomly allocated into two groups: Abdominopelvic training by virtual reality – APT_VR (n=30) and PFMT using a gym ball – PFMT_GB (n=30). Both types of training were supervised by the same physical therapist, during 10 sessions each, for 30 minutes. The participants’ PFM strength was evaluated by digital palpation and vaginal dynamometry, considering three different parameters: maximum strength, average strength and endurance. An intention-to-treat approach was used to analyze the participants according to original groups. Results No significant between-group differences were observed in most analyzed parameters. The outcome endurance was higher in the APT_VR group (p=0.003; effect size=0.89; mean difference=1.37; 95% CI=0.46 to 2.28). Conclusion Both protocols have improved the overall PFM strength, suggesting that both are equally beneficial and can be used in clinical practice. Muscle endurance was higher in patients who trained using virtual reality. PMID:27437716

  14. Effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by parkinson’s disease

    PubMed Central

    Byeon, Haewon

    2016-01-01

    [Purpose] This study aimed to investigate the effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by Parkinson’s disease. [Subjects and Methods] The subjects of this study were 18 patients who received simultaneous application of postural techniques and expiratory muscle strength training and 15 patients who received expiratory muscle strength training only. Postural techniques were conducted in the order of chin tucking, head rotation, head tilting, bending head back, and lying down, while expiratory muscle strength training was conducted at a resistance level of about 70% of the maximal expiratory pressure. Swallowing recovery was assessed by using the Functional Dysphagia Scale based on videofluoroscopic studies. [Results] The mean value obtained in the videofluoroscopic studies for both groups decreased after the treatment. In the postural techniques plus expiratory muscle strength training group, the decrease was significantly greater than that in the expiratory muscle strength training-only group. [Conclusion] The results imply that simultaneous performance of postural techniques and expiratory muscle strength training is more effective than expiratory muscle strength training alone when applied in the swallowing rehabilitation for patients with dysphagia caused by Parkinson’s disease. PMID:27390429

  15. Reduced force of diaphragm muscle fibers in patients with chronic thromboembolic pulmonary hypertension.

    PubMed

    Manders, Emmy; Bonta, Peter I; Kloek, Jaap J; Symersky, Petr; Bogaard, Harm-Jan; Hooijman, Pleuni E; Jasper, Jeff R; Malik, Fady I; Stienen, Ger J M; Vonk-Noordegraaf, Anton; de Man, Frances S; Ottenheijm, Coen A C

    2016-07-01

    Patients with pulmonary hypertension (PH) suffer from inspiratory muscle weakness. However, the pathophysiology of inspiratory muscle dysfunction in PH is unknown. We hypothesized that weakness of the diaphragm, the main inspiratory muscle, is an important contributor to inspiratory muscle dysfunction in PH patients. Our objective was to combine ex vivo diaphragm muscle fiber contractility measurements with measures of in vivo inspiratory muscle function in chronic thromboembolic pulmonary hypertension (CTEPH) patients. To assess diaphragm muscle contractility, function was studied in vivo by maximum inspiratory pressure (MIP) and ex vivo in diaphragm biopsies of the same CTEPH patients (N = 13) obtained during pulmonary endarterectomy. Patients undergoing elective lung surgery served as controls (N = 15). Muscle fiber cross-sectional area (CSA) was determined in cryosections and contractility in permeabilized muscle fibers. Diaphragm muscle fiber CSA was not significantly different between control and CTEPH patients in both slow-twitch and fast-twitch fibers. Maximal force-generating capacity was significantly lower in slow-twitch muscle fibers of CTEPH patients, whereas no difference was observed in fast-twitch muscle fibers. The maximal force of diaphragm muscle fibers correlated significantly with MIP. The calcium sensitivity of force generation was significantly reduced in fast-twitch muscle fibers of CTEPH patients, resulting in a ∼40% reduction of submaximal force generation. The fast skeletal troponin activator CK-2066260 (5 μM) restored submaximal force generation to levels exceeding those observed in control subjects. In conclusion, diaphragm muscle fiber contractility is hampered in CTEPH patients and contributes to the reduced function of the inspiratory muscles in CTEPH patients. PMID:27190061

  16. Dietary protein intake is associated with better physical function and muscle strength among elderly women.

    PubMed

    Isanejad, Masoud; Mursu, Jaakko; Sirola, Joonas; Kröger, Heikki; Rikkonen, Toni; Tuppurainen, Marjo; Erkkilä, Arja T

    2016-04-14

    Dietary protein intake might be beneficial to physical function (PF) in the elderly. We examined the cross-sectional and prospective associations of protein intake of g/kg body weight (BW), fat mass (FM) and lean mass (LM) with PF in 554 women aged 65·3-71·6 years belonging to the Osteoporosis Risk Factor and Prevention Fracture Prevention Study. Participants filled a questionnaire on lifestyle factors and 3-d food record in 2002. Body composition was measured by dual-energy X-ray absorptiometry, and PF measures were performed at baseline and at 3-year follow-up. Sarcopaenia was defined using European Working Group on Sarcopenia in Older People criteria. At the baseline, women with higher protein intake (≥ 1·2 g/kg BW) had better performance in hand-grip strength/body mass (GS/BM) (P=0·001), knee extension/BM (P=0·003), one-leg stance (P=0·047), chair rise (P=0·043), squat (P=0·019), squat to the ground (P=0·001), faster walking speed for 10 m (P=0·005) and higher short physical performance battery score (P=0·004) compared with those with moderate and lower intakes (0·81-1·19 and ≤ 0·8 g/kg BW, respectively). In follow-up results, higher protein intake was associated with less decline in GS/BM, one-leg stance and tandem walk for 6 m over 3 years. Overall, results were no longer significant after controlling for FM. Associations were detected between protein intake and PF in non-sarcopaenic women but not in sarcopaenic women, except for change of GS (P=0·037). Further, FM but not LM was negatively associated with PF measures (P<0·050). This study suggests that higher protein intake and lower FM might be positively associated with PF in elderly women. PMID:26857389

  17. Knee muscle strength correlates with joint cartilage T2 relaxation time in young participants with risk factors for osteoarthritis.

    PubMed

    Macías-Hernández, Salvador Israel; Miranda-Duarte, Antonio; Ramírez-Mora, Isabel; Cortés-González, Socorro; Morones-Alba, Juan Daniel; Olascoaga-Gómez, Andrea; Coronado-Zarco, Roberto; Soria-Bastida, María de Los Angeles; Nava-Bringas, Tania Inés; Cruz-Medina, Eva

    2016-08-01

    The objective of this study is to correlate T2 relaxation time (T2RT), measured by magnetic resonance imaging (MRI) with quadriceps and hamstring strength in young participants with risk factors for knee osteoarthritis (OA). A descriptive cross-sectional study was conducted with participants between 20 and 40 years of age, without diagnosis of knee OA. Their T2 relaxation time was measured through MRI, and their muscle strength (MS) was measured with an isokinetic dynamometer. Seventy-one participants were recruited, with an average age of 28.3 ± 5.5 years; 39 (55 %) were females. Negative correlations were found between T2RT and quadriceps peak torque (QPT) in males in the femur r = -0.46 (p = 0.01), tibia r = -0.49 (p = 0.02), and patella r = -0.44 (p = 0.01). In women, correlations were found among the femur r = -0.43 (p = 0.01), tibia r = -0.61 (p = 0.01), and patella r = -0.32 (p = 0.05) and among hamstring peak torque (HPT), in the femur r = -0.46 (p = 0.01), hamstring total work (HTW) r = -0.42 (p = 0.03), and tibia r = -0.33 (p = 0.04). Linear regression models showed good capacity to predict T2RT through QPT in both genders. The present study shows that early changes in femoral, tibial, and patellar cartilage are significantly correlated with MS, mainly QPT, and that these early changes might be explained by MS, which could play an important role in pre-clinical phases of the disease. PMID:27334115

  18. Model analysis of respiratory responses to inspiratory resistive loads.

    PubMed

    Zin, W A; Rossi, A; Milic-Emili, J

    1983-11-01

    Based on experimental inspiratory driving pressure waveforms and active respiratory impedance data of anesthetized cats, we made model predictions of the factors that determine the immediate (first loaded breath) intrinsic (i.e., nonneural) tidal volume compensation to added inspiratory resistive loads. The time course of driving pressure (P) was given by P = atb, where a is the pressure at 1 s from onset of inspiration and represents the intensity of neuromuscular drive, t is time, and b is a dimensionless index of the shape of the driving pressure wave. For a given value of active respiratory impedance, tidal volume compensation to added resistive loads increases with increasing inspiratory duration and decreasing value of b but is independent of a. Model predictions of load compensation are compared to experimental results. PMID:6643192

  19. Effects of resistance training with moderate vs heavy loads on muscle mass and strength in the elderly: A meta-analysis.

    PubMed

    Csapo, R; Alegre, L M

    2016-09-01

    The purpose of the present study was to perform a meta-analysis to compare the efficacy of heavy (∼80% of one repetition maximum, 1RM) vs light-moderate load (∼45% 1RM) resistance training (RT) programs in inducing strength gains and skeletal muscle hypertrophy in elderly people. To assess the role of training volumes, studies in which training protocols were matched for mechanical work were independently analyzed. In all 15 studies included (448 subjects, age 67.8 years), when comparing heavy with light-moderate loads, strength gains tended to be larger following RT with higher intensities of load, with the resulting total population effect being μ = 0.430 (P = 0.060). Effect sizes were substantially smaller in "work-matched" studies (μ = 0.297, P = 0.003). Training with higher loads also provoked marginally larger gains in muscle size, although the degree of training-induced muscle hypertrophy was generally small (0.056 < μ < 0.136). To conclude, provided a sufficient number of repetitions is performed, RT at lower than traditionally recommended intensities of load may suffice to induce substantial gains in muscle strength in elderly cohorts. PMID:26302881

  20. Effect of the Herbal Drug Guilu Erxian Jiao on Muscle Strength, Articular Pain, and Disability in Elderly Men with Knee Osteoarthritis

    PubMed Central

    Tsai, Chen-Chen; Chou, Yin-Yi; Chen, Yi-Ming; Tang, Yih-Jing; Ho, Hui-Ching; Chen, Der-Yuan

    2014-01-01

    Background. Guilu Erxian Jiao (GEJ) is a widely used Chinese herbal remedy for knee osteoarthritis, but its clinical efficacy is unknown. Methods. We enrolled 42 elderly male patients with knee OA, including 21 patients who received the herbal drug GEJ as the case group and 21 patients who did not receive GEJ as the control group. The effects of 12 weeks of GEJ treatment on muscle strength of lower limbs were measured by a Biodex dynamometer, with disability evaluated on the Lequesne index and articular pain measured on the visual analog scale (VAS) between the two groups on the baseline and after treatment. Results. There were significant increases in the levels of muscle strength of TQ/BW-ext-dominant and TQ/BW-flex-dominant between the two groups after treatment (P < 0.05). There were also significant increases in muscle strength of knee extensor muscles in the GEJ-treated group (n = 21) self-controlled before and after 12 weeks of treatment (all P < 0.01). There were significant decreases in articular pain (P < 0.01) and Lequesne index scores (P < 0.01) in the GEJ-treated group when compared to the non-GEJ-treated group. Conclusions. Our results showed that GEJ is effective and is tolerated well in elderly men with knee OA. PMID:25309612

  1. Influence of ionic strength on the time course of force development and phosphate release by dogfish muscle fibres.

    PubMed

    West, Timothy G; Ferenczi, Michael A; Woledge, Roger C; Curtin, N A

    2005-09-15

    We measured the effects of ionic strength (IS), 200 (standard) and 400 mmol l(-1) (high), on force and ATP hydrolysis during isometric contractions of permeabilized white fibres from dogfish myotomal muscle at their physiological temperature, 12 degrees C. One goal was to test the validity of our kinetic scheme that accounts for energy release, work production and ATP hydrolysis. Fibres were activated by flash photolysis of the P(3)-1-(2 nitrophenyl) ethyl ester of ATP (NPE-caged ATP), and time-resolved phosphate (P(i)) release was detected with the fluorescent protein MDCC-PBP, N-(2[1-maleimidyl]ethyl)-7-diethylamino-coumarin-3-carboxamide phosphate binding protein. High IS slowed the transition from rest to contraction, but as the fibres approached the isometric force plateau they showed little IS sensitivity. By 0.5 s of contraction, the force and the rate of P(i) release at standard and high IS values were not significantly different. A five-step reaction mechanism was used to account for the observed time courses of force and P(i) release in all conditions explored here. Only the rate constants for reactions of ATP, ADP and P(i) with the contractile proteins varied with IS, thus suggesting that the actin-myosin interactions are largely non-ionic. Our reaction scheme also fits previous results for intact fibres. PMID:16037082

  2. Vitamin C and E supplementation alters protein signalling after a strength training session, but not muscle growth during 10 weeks of training

    PubMed Central

    Paulsen, G; Hamarsland, H; Cumming, K T; Johansen, R E; Hulmi, J J; Børsheim, E; Wiig, H; Garthe, I; Raastad, T

    2014-01-01

    This study investigated the effects of vitamin C and E supplementation on acute responses and adaptations to strength training. Thirty-two recreationally strength-trained men and women were randomly allocated to receive a vitamin C and E supplement (1000 mg day−1 and 235 mg day−1, respectively), or a placebo, for 10 weeks. During this period the participants’ training involved heavy-load resistance exercise four times per week. Muscle biopsies from m. vastus lateralis were collected, and 1 repetition maximum (1RM) and maximal isometric voluntary contraction force, body composition (dual-energy X-ray absorptiometry), and muscle cross-sectional area (magnetic resonance imaging) were measured before and after the intervention. Furthermore, the cellular responses to a single exercise session were assessed midway in the training period by measurements of muscle protein fractional synthetic rate and phosphorylation of several hypertrophic signalling proteins. Muscle biopsies were obtained from m. vastus lateralis twice before, and 100 and 150 min after, the exercise session (4 × 8RM, leg press and knee-extension). The supplementation did not affect the increase in muscle mass or the acute change in protein synthesis, but it hampered certain strength increases (biceps curl). Moreover, increased phosphorylation of p38 mitogen-activated protein kinase, Extracellular signal-regulated protein kinases 1 and 2 and p70S6 kinase after the exercise session was blunted by vitamin C and E supplementation. The total ubiquitination levels after the exercise session, however, were lower with vitamin C and E than placebo. We concluded that vitamin C and E supplementation interfered with the acute cellular response to heavy-load resistance exercise and demonstrated tentative long-term negative effects on adaptation to strength training. PMID:25384788

  3. Association of Serum Asymmetric Dimethylarginine With Muscle Strength and Gait Speed: A Cross-Sectional Study of the HEIJO-KYO Cohort.

    PubMed

    Obayashi, Kenji; Saeki, Keigo; Maegawa, Taeko; Sakai, Takahide; Kitagawa, Maiko; Otaki, Naoto; Kataoka, Hiroshi; Kurumatani, Norio

    2016-05-01

    Muscle strength and gait speed are related with functional limitations and disabilities and also predict cardiovascular and all-cause mortality. Nitric oxide (NO) plays an important role in regulating physiological process in skeletal muscles; however, the association between serum asymmetric dimethylarginine (ADMA) level, an endogenous competitive inhibitor of NO synthesis, and physical performance has not yet been studied. We investigated the associations of serum ADMA level with muscle strength and usual gait speed in a cross-sectional study of 550 elderly individuals (mean age, 71.2 ± 6.6 years). Mean ADMA level was 0.45 ± 0.06 µmol/L; mean grip and quadriceps strengths were 27.7 ± 8.4 kg and 165.1 ± 81.6 Nm, respectively; and mean gait speed was 1.37 ± 0.30 m/s. In multivariate linear regression analysis adjusted for potential confounding factors (age, gender, body weight, smoking and drinking status, household income, hypertension, diabetes, renal function, and physical activity), higher serum ADMA level was significantly associated with lower grip and quadriceps strengths and slower gait speed (grip strength: β, -1.257; 95% confidence interval [CI], -1.990 to -0.525; p = 0.001; quadriceps strength: β, -11.730; 95% CI, -20.924 to -2.536; p = 0.012; gait speed: β, -0.065; 95% CI, -0.108 to -0.022; p = 0.003). Our findings indicate the significant association between serum ADMA level and physical performance among elderly individuals, which was independent of the important potential confounders. © 2015 American Society for Bone and Mineral Research. PMID:26704561

  4. A myostatin inhibitor (propeptide-Fc) increases muscle mass and muscle fiber size in aged mice but does not increase bone density or bone strength.

    PubMed

    Arounleut, Phonepasong; Bialek, Peter; Liang, Li-Fang; Upadhyay, Sunil; Fulzele, Sadanand; Johnson, Maribeth; Elsalanty, Mohammed; Isales, Carlos M; Hamrick, Mark W

    2013-09-01

    Loss of muscle and bone mass with age are significant contributors to falls and fractures among the elderly. Myostatin deficiency is associated with increased muscle mass in mice, dogs, cows, sheep and humans, and mice lacking myostatin have been observed to show increased bone density in the limb, spine, and jaw. Transgenic overexpression of myostatin propeptide, which binds to and inhibits the active myostatin ligand, also increases muscle mass and bone density in mice. We therefore sought to test the hypothesis that in vivo inhibition of myostatin using an injectable myostatin propeptide (GDF8 propeptide-Fc) would increase both muscle mass and bone density in aged (24 mo) mice. Male mice were injected weekly (20 mg/kg body weight) with recombinant myostatin propeptide-Fc (PRO) or vehicle (VEH; saline) for four weeks. There was no difference in body weight between the two groups at the end of the treatment period, but PRO treatment significantly increased mass of the tibialis anterior muscle (+ 7%) and increased muscle fiber diameter of the extensor digitorum longus (+ 16%) and soleus (+ 6%) muscles compared to VEH treatment. Bone volume relative to total volume (BV/TV) of the femur calculated by microCT did not differ significantly between PRO- and VEH-treated mice, and ultimate force (Fu), stiffness (S), toughness (U) measured from three-point bending tests also did not differ significantly between groups. Histomorphometric assays also revealed no differences in bone formation or resorption in response to PRO treatment. These data suggest that while developmental perturbation of myostatin signaling through either gene knockout or transgenic inhibition may alter both muscle and bone mass in mice, pharmacological inhibition of myostatin in aged mice has a more pronounced effect on skeletal muscle than on bone. PMID:23832079

  5. Model analysis of tidal volume response to inspiratory elastic loads.

    PubMed

    Zin, W A; Rossi, A; Zocchi, L; Milic-Emili, J

    1984-07-01

    Based on experimental inspiratory driving pressure waveforms and active respiratory impedance data of anesthetized cats, we made model predictions of the factors that determine the immediate (first loaded breath) intrinsic (i.e., nonneural) tidal volume compensation to added inspiratory elastic loads. The time course of driving pressure (P) was given by P = atb, where a is the pressure at 1 s from onset of inspiration and represents the intensity of neuromuscular drive, t is time, and b is an index of the shape of the driving pressure wave. For a given active respiratory impedance, tidal volume compensation to added elastic loads decreases with increasing inspiratory duration and decreasing value of b but is independent of a. We have also assessed the validity of the "effective elastance" (Lynne-Davies et al., J. Appl. Physiol. 30: 512-516, 1971) as a predictor of tidal volume responses to elastic loads. In absence of vagal feedback, the effective elastance appears to be a reliable predictor, except for short inspiratory duration and a very high intrinsic resistance. PMID:6469787

  6. Collagen peptide supplementation in combination with resistance training improves body composition and increases muscle strength in elderly sarcopenic men: a randomised controlled trial.

    PubMed

    Zdzieblik, Denise; Oesser, Steffen; Baumstark, Manfred W; Gollhofer, Albert; König, Daniel

    2015-10-28

    Protein supplementation in combination with resistance training may increase muscle mass and muscle strength in elderly subjects. The objective of this study was to assess the influence of post-exercise protein supplementation with collagen peptides v. placebo on muscle mass and muscle function following resistance training in elderly subjects with sarcopenia. A total of fifty-three male subjects (72·2 (sd 4·68) years) with sarcopenia (class I or II) completed this randomised double-blind placebo-controlled study. All the participants underwent a 12-week guided resistance training programme (three sessions per week) and were supplemented with either collagen peptides (treatment group (TG)) (15 g/d) or silica as placebo (placebo group (PG)). Fat-free mass (FFM), fat mass (FM) and bone mass (BM) were measured before and after the intervention using dual-energy X-ray absorptiometry. Isokinetic quadriceps strength (IQS) of the right leg was determined and sensory motor control (SMC) was investigated by a standardised one-leg stabilisation test. Following the training programme, all the subjects showed significantly higher (P<0·01) levels for FFM, BM, IQS and SMC with significantly lower (P<0·01) levels for FM. The effect was significantly more pronounced in subjects receiving collagen peptides: FFM (TG +4·2 (sd 2·31) kg/PG +2·9 (sd 1·84) kg; P<0·05); IQS (TG +16·5 (sd 12·9) Nm/PG +7·3 (sd 13·2) Nm; P<0·05); and FM (TG -5·4 (sd 3·17) kg/PG -3·5 (sd 2·16) kg; P<0·05). Our data demonstrate that compared with placebo, collagen peptide supplementation in combination with resistance training further improved body composition by increasing FFM, muscle strength and the loss in FM. PMID:26353786

  7. Serotonin and Histamine Therapy Increases Tetanic Forces of Myoblasts, Reduces Muscle Injury, and Improves Grip Strength Performance of Dmd(mdx) Mice.

    PubMed

    Gurel, Volkan; Lins, Jeremy; Lambert, Kristyn; Lazauski, Joan; Spaulding, James; McMichael, John

    2015-01-01

    Duchenne muscular dystrophy (DMD) is a recessive X-linked fatal disorder caused by a mutation in the dystrophin gene. Although several therapeutic approaches have been studied, none has led to substantial long-term effects in patients. The aim of this study was to test a serotonin and histamine (S&H) combination on human skeletal myoblasts and Dmd(mdx) mice for its effects on muscle strength and injury. Normal human bioartificial muscles (BAMs) were treated, and muscle tetanic forces and muscle injury tests were performed using the MyoForce Analysis System. Dmd(mdx) mice, the murine model of DMD, were administered serotonin, histamine, or S&H combination twice daily for 6 weeks, and functional performance tests were conducted once a week. The S&H combination treatment caused significant increases in tetanic forces at all time points and concentrations tested as compared to the saline controls. Dose response of the BAMs to the treatment demonstrated a significant increase in force generation at all concentrations compared to the controls after 3 to 4 days of drug treatment. The highest 3 concentrations had a significant effect on lowering contractile-induced injury as measured by a reduction in the release of adenylate kinase. Histamine-only and S&H treatments improved grip strength of Dmd(mdx) mice, whereas serotonin-only treatment resulted in no significant improvement in muscle strength. The results of this study indicate that S&H therapy might be a promising new strategy for muscular dystrophies and that the mechanism should be further investigated. PMID:26740813

  8. The Effect of Concentric Isokinetic Strength Training of the Quadriceps Femoris on Electromyography and Muscle Strength in the Trained and Untrained Limb.

    ERIC Educational Resources Information Center

    Evetovich, Tammy K.; Housh, Terry J.; Housh, Dona J.; Johnson, Glen O.; Smith, Douglas B.; Ebersole, Kyle T.

    2001-01-01

    Examined the effects of unilateral concentric isokinetic leg extension training on peak torque and electromyographic (EMG) responses in trained and untrained limbs. Adult men participated in training and control groups. Overall, unilateral concentric isokinetic strength training induced strength increases in trained as well as untrained limbs.…