Sunita Mathur

Interval versus continuous training in individuals with chronic obstructive pulmonary disease--a systematic review.

Background In patients with chronic obstructive pulmonary disease (COPD), interval exercise has gained recent attention as a possible means of achieving greater physiological training effects compared with continuous exercise. The primary aim of this systematic review was to compare the effects of interval versus continuous training on peak oxygen uptake, peak power, 6 minute walk test (6MWT) distance and health-related quality of life in individuals with COPD. Methods Randomised controlled trials comparing the effects of interval versus continuous training in patients with COPD were identified after searches of six databases and reference lists of appropriate studies in May 2009. Two reviewers independently assessed study quality. Weighted mean differences (WMD) with 95% CIs were calculated using a random effects model for measures of exercise capacity and health-related quality of life. Results: Eight randomised controlled trials, with a total of 388 patients with COPD, met the inclusion criteria. No significant differences were found for peak power (WMD 1 W, 95% CI −1 to 3) or peak oxygen uptake (WMD −0.04 l/min, 95% CI −0.13 to 0.05) between interval and continuous training. The WMD for the Chronic Respiratory Questionnaire dyspnoea score was −0.2 units (95% CI −0.5 to 0.0). There was no difference in 6MWT distance between groups (WMD 4 m, 95% CI −15 to 23). Conclusions Interval and continuous training modalities did not differ in their effect on measures of exercise capacity or health-related quality of life. Interval training may be considered as an alternative to continuous training in patients with varying degrees of COPD severity.

Impairments in Systems Underlying Control of Balance in COPD

BACKGROUND Although balance deficits are increasingly recognized in COPD, little is known regarding the disordered subcomponents underlying the control of balance. We aimed to determine the specific components of balance that are impaired in COPD and to investigate the association among balance, peripheral muscle strength, and physical activity. METHODS Balance, physical activity, and lower extremity muscle strength were assessed in 37 patients with COPD and 20 age-matched healthy control subjects using the Balance Evaluation Systems Test (BESTest), the Physical Activity Scale for the Elderly, and an isokinetic dynamometer, respectively. A subset of subjects (20 patients with COPD and 20 control subjects) underwent a second testing session in which postural perturbations were delivered using a lean-and-release system. RESULTS Subjects with COPD (age, 71 ± 7 years; FEV(1), 39% ± 16% predicted) exhibited significantly lower scores than did control subjects (age, 67 ± 9 years) on all of the BESTest subscales (all P < .001). In response to anterior perturbations, subjects with COPD showed a longer time to foot-off (P = .027) and foot contact (P = .018), and a longer duration anticipatory phase (P = .008) compared with control subjects. Muscle strength (P = .008) and self-reported physical activity (P = .033) explained 35% of the variance in balance in subjects with COPD. CONCLUSIONS Individuals with COPD exhibit impairments in all balance subcomponents and demonstrate slower reaction times in response to perturbations. Deficits in balance are associated with reduced physical activity levels and skeletal muscle weakness.

Exercise training after lung transplantation: a systematic review.

BACKGROUND Lung transplant recipients experience persistent impairments in exercise capacity and skeletal muscle function despite a vast improvement in lung function after transplantation. Exercise training may be beneficial in improving exercise capacity in lung transplant recipients. A systematic review was undertaken to examine the evidence for exercise training on functional outcomes in lung transplant recipients. METHODS Studies were identified by searching electronic databases and scanning reference lists. Only randomized controlled trials, controlled trials, and prospective cohorts were included in the review. Seven studies met the inclusion criteria. Study quality was assessed using the Physiotherapy Evidence Database, Jadad, and Downs scales. RESULTS The overall quality of studies was fair to moderate in assessing the effect of exercise training on maximal and functional exercise capacity, skeletal muscle function, and lumbar bone mineral density. Every study reported significant improvements in these outcomes. Some studies lacked randomization and/or a control group, so it was not possible to separate the effects of training with the natural recovery process after lung transplantation. CONCLUSION Some evidence was found to support that a period of structured exercise training could improve maximal and functional exercise capacity, skeletal muscle strength, and lumbar bone mineral density in lung transplant recipients. Further studies are needed to determine the potential for exercise training to optimize these functional outcomes and to develop optimal guidelines for exercise prescription in the lung transplant population.

The First Physical Therapy Summit on Global Health: Implications and Recommendations for the 21st century

The First Physical Therapy Summit on Global Health was convened at the 2007 World Confederation for Physical Therapy (WCPT) Congress to vision practice in the 21st century and, in turn, entry-level education and research, as informed by epidemiological indicators, and consistent with evidence-based noninvasive interventions, the hallmark of physical therapy. The Summit and its findings were informed by WHO data and validated through national databases of the countries of the five WCPT regions. The health priorities based on mortality were examined in relation to proportions of physical therapists practicing in the areas of regional priorities and of the curricula in entry-level programs. As a validation check and to contextualize the findings, input from members of the 800 Summit participants was integrated and international consultants refined the recommendations. Lifestyle-related conditions (ischemic heart disease, smoking-related conditions, hypertension, stroke, cancer, and diabetes) were leading causes of premature death across regions. Contemporary definitions of physical therapy support that the profession has a leading role in preventing, reversing, as well as managing lifestyle-related conditions. The proportions of practitioners practicing primarily in these priority areas and of the entry-level curricula based on these priorities were low. The proportions of practitioners in priority areas and entry-level curricula devoted to lifestyle-related conditions warrant being better aligned with the prevalence of these conditions across regions in the 21st century. A focus on clinical competencies associated with effective health education and health behavior change formulates the basis for The Second Physical Therapy Summit on Global Health.

Measurement of peripheral muscle strength in individuals with chronic obstructive pulmonary disease: a systematic review.

PURPOSE: Reduced maximal, peripheral muscle strength is associated with exercise intolerance in patients with chronic obstructive pulmonary disease (COPD). Therefore, it is important to accurately evaluate muscle strength to identify patients with muscle weakness and to prescribe adequate loads for resistance training. The objective here was to systematically identify and summarize the literature on measurement of peripheral muscle strength in individuals with COPD and to make recommendations for strength testing in clinical and research settings. METHODS: A literature search was conducted of electronic databases between 1999 and 2009 of all English language articles utilizing muscle strength measurements. RESULTS: The search resulted in retrieval of 178 articles, of which 66 were reviewed. Isometric muscle strength was measured using handgrip (n = 30), strain gauge (n = 15), computerized dynamometer (n = 13), magnetic stimulation (n = 8), handheld dynamometer (n = 6), or manual testing (n = 3). Isotonic muscle strength was measured using a hydraulic system (n = 3) or 1-repetition maximum (n = 9), and isokinetic muscle strength was measured using computerized dynamometer (n = 16). Methodological issues such as limb position, number of trials, subject familiarization, test instructions, rest periods, and muscle group tested were all identified as important variables to consider when developing a strength-testing protocol. CONCLUSION: Muscle strength has been measured in people with COPD using similar methods as in other clinical populations. Each method presents advantages and disadvantages that need to be considered when selecting the most relevant measure. Standardization of the test procedures is essential in both clinical and research settings to obtain valid and reliable measurements of muscle strength.

Pulmonary rehabilitation in lung transplant candidates

BACKGROUND While awaiting lung transplantation, candidates may participate in pulmonary rehabilitation to improve their fitness for surgery. However, pulmonary rehabilitation outcomes have not been systematically evaluated in lung transplant candidates. METHODS This investigation was a retrospective cohort study of 345 pre-transplant pulmonary rehabilitation participants who received a lung transplant between January 2004 and June 2009 and had available pre-transplant exercise data. Data extracted included: 6-minute walk tests at standard intervals; exercise training details; health-related quality-of-life (HRQL) measures; and early post-transplant outcomes. Paired t-tests were used to examine changes in the 6MW distance (6MWD), exercise training volume and HRQL during the pre-transplant period. We evaluated the association between pre-transplant 6MWD and transplant hospitalization outcomes. RESULTS The final 6MWD prior to transplantation was only 15 m less than the listing 6MWD (n = 200; p = 0.002). Exercise training volumes increased slightly from the start of the pulmonary rehabilitation program until transplant: treadmill, increase 0.69 ml/kg/min (n = 238; p < 0.0001); biceps resistance training, 18 lbs. × reps (n = 286; p < 0.0001); and quadriceps resistance training, 15 lbs. × reps (n = 278; p < 0.0001). HRQL measures declined. A greater final 6MWD prior to transplant correlated with a shorter length of stay in the hospital (n = 207; p = 0.003). CONCLUSIONS Exercise capacity and training volumes are well preserved among lung transplant candidates participating in pulmonary rehabilitation, even in the setting of severe, progressive lung disease. Participants with greater exercise capacity prior to transplantation have more favorable early post-transplant outcomes.

Overexpression of insulin-like growth factor-1 attenuates skeletal muscle damage and accelerates muscle regeneration and functional recovery after disuse

•  What is the central question of this study? Insulin‐like growth factor‐1 (IGF‐1) promotes muscle hypertrophy, but no studies have investigated the effect of IGF‐1 on the susceptibility of atrophied muscles to reloading‐induced muscle injury. •  What is the main finding and what is its importance? We employed a comprehensive set of methods, including muscle physiological measurements, molecular biology techniques and non‐invasive magnetic resonance imaging. The results concurrently demonstrate that local overexpression of IGF‐1 in a primary antigravity muscle protects the muscle from reloading‐induced muscle damage and accelerates muscle regeneration and functional recovery following cast immobilization. These findings add new physiological significance to the benefits of IGF‐1 on skeletal muscle mass and force generation during varied loading conditions.

The Second Physical Therapy Summit on Global Health: developing an action plan to promote health in daily practice and reduce the burden of non-communicable diseases

Abstract Based on indicators that emerged from The First Physical Therapy Summit on Global Health (2007), the Second Summit (2011) identified themes to inform a global physical therapy action plan to integrate health promotion into practice across the World Confederation for Physical Therapy (WCPT) regions. Working questions were: (1) how well is health promotion implemented within physical therapy practice; and (2) how might this be improved across five target audiences (i.e. physical therapist practitioners, educators, researchers, professional body representatives, and government liaisons/consultants). In structured facilitated sessions, Summit representatives (n = 32) discussed: (1) within WCPT regions, what is working and the challenges; and (2) across WCPT regions, what are potential directions using World CaféTM methodology. Commonalities outweighed differences with respect to strategies to advance health-focused physical therapy as a clinical competency across regions and within target audiences. Participants agreed that health-focused practice is a professional priority, and a strategic action plan was needed to develop it as a clinical competency. The action plan and recommendations largely paralleled the principles and objectives of the World Health Organization’s non-communicable diseases action plan. A third Summit planned for 2015 will provide a mechanism for follow-up to evaluate progress in integrating health-focused physical therapy within the profession.

Structural alterations of skeletal muscle in copd

Background: Chronic obstructive pulmonary disease (COPD) is a respiratory disease associated with a systemic inflammatory response. Peripheral muscle dysfunction has been well characterized in individuals with COPD and results from a complex interaction between systemic and local factors. Objective: In this narrative review, we will describe muscle wasting in people with COPD, the associated structural changes, muscle regenerative capacity and possible mechanisms for muscle wasting. We will also discuss how structural changes relate to impaired muscle function and mobility in people with COPD. Key Observations: Approximately 30–40% of individuals with COPD experience muscle mass depletion. Furthermore, muscle atrophy is a predictor of physical function and mortality in this population. Associated structural changes include a decreased proportion and size of type-I fibers, reduced oxidative capacity and mitochondrial density mainly in the quadriceps. Observations related to impaired muscle regenerative capacity in individuals with COPD include a lower proportion of central nuclei in the presence or absence of muscle atrophy and decreased maximal telomere length, which has been correlated with reduced muscle cross-sectional area. Potential mechanisms for muscle wasting in COPD may include excessive production of reactive oxygen species (ROS), altered amino acid metabolism and lower expression of peroxisome proliferator-activated receptors-gamma-coactivator 1-alpha mRNA. Despite a moderate relationship between muscle atrophy and function, impairments in oxidative metabolism only seems weakly related to muscle function. Conclusion: This review article demonstrates the cellular modifications in the peripheral muscle of people with COPD and describes the evidence of its relationship to muscle function. Future research will focus on rehabilitation strategies to improve muscle wasting and maximize function.

Is Quadriceps Endurance Reduced in COPD?: A Systematic Review

BACKGROUND Although the aerobic profile of the quadriceps muscle is reduced in COPD, there is conflicting evidence regarding whether this leads to reduced quadriceps muscle endurance. We, therefore, performed a systematic review of studies comparing quadriceps endurance in individuals with COPD with that in healthy control subjects. METHODS Relevant studies were identified by searching six electronic databases (1946-2011). Full-text articles were obtained after two researchers independently reviewed the abstracts. The results were combined in a random effects meta-analysis, and metaregression models were fitted to assess the influence of the type of measurement. RESULTS Data were extracted from 21 studies involving 728 individuals with COPD and 440 healthy control subjects. Quadriceps endurance was reduced in those with COPD compared with healthy control subjects (standardized mean difference, 1.16 [95% CI, 1.02-1.30]; P < .001) with a 44.5 s (4.5-84.5 s; P = .029) reduction in COPD (large effect size) when measured using a nonvolitional technique. The relationship between quadriceps endurance in those with COPD and control subjects did not differ when comparing nonvolitional and volitional techniques (P = .22) or when high- or low-intensity tasks (P = .44) were undertaken. CONCLUSIONS Quadriceps endurance is reduced in individuals with COPD compared with healthy control subjects, independent of the type of task performed.