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Background: Despite the wide-ranging benefits of pulmonary rehabilitation, conflicting results remain regarding whether people with COPD can improve their peak oxygen uptake (V˙O 2peak) with aerobic training., Research Question: The goal of this study was to investigate the effect of aerobic training and exercise prescription on V˙O 2peak in COPD., Study Design and Methods: A systematic review was performed by using MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, and Cochrane databases for all studies measuring V˙O 2peak prior to and following supervised lower-limb aerobic training in COPD. A random effects meta-analysis limited to randomized controlled trials comparing aerobic training vs usual care was conducted. Other study designs were included in a secondary meta-analysis and meta-regression to investigate the influence of program and patient factors on outcome., Results: A total of 112 studies were included (participants, N = 3,484): 21 controlled trials (n = 489), of which 13 were randomized (n = 288) and 91 were uncontrolled (n = 2,995) studies. Meta-analysis found a moderate positive change in V˙O 2peak (standardized mean difference, 0.52; 95% CI, 0.34-0.69) with the intervention. The change in V˙O 2peak was positively associated with target duration of exercise session (P = .01) and, when studies > 1 year duration were excluded, greater total volume of exercise training (P = .01). Similarly, the change in V˙O 2peak was greater for programs > 12 weeks compared with those 6 to 12 weeks when adjusted for age and sex. However, reported prescribed exercise intensity (P = .77), training modality (P > .35), and mode (P = .29) did not affect V˙O 2peak . Cohorts with more severe airflow obstruction exhibited smaller improvements in V˙O 2peak (P < .001)., Interpretation: Overall, people with COPD achieved moderate improvements in V˙O 2peak through supervised aerobic training. There is sufficient evidence to show that programs with greater total exercise volume, including duration of exercise session and program duration, are more effective. Reduced effects in severe disease suggest alternative aerobic training methods may be needed in this population., Clinical Trial Registration: PROSPERO; No.: CRD42018099300; URL: https://www.crd.york.ac.uk/prospero/., (Copyright © 2020 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Rationale: In patients with chronic obstructive pulmonary disease (COPD), partitioned exercise training using one-legged cycling leads to greater improvements in peak oxygen uptake than conventional two-legged cycling., Objectives: We evaluated the feasibility of incorporating one-legged cycling as the principal aerobic training modality for pulmonary rehabilitation in COPD., Methods: Physiotherapists underwent four teaching sessions about the principles and practical implementation of one-legged cycling training. Patients enrolled in a pulmonary rehabilitation program underwent 6-8 weeks of training in which one-legged cycling three times per week was the principal aerobic exercise activity. Participants cycled for 15 minutes with each leg, in each session. An incremental cardiopulmonary exercise test was completed before and after pulmonary rehabilitation along with standard pulmonary rehabilitation outcome measures. Participants and physiotherapists completed a satisfaction survey at the end of the program., Measurements and Main Results: A total of 22 out of 32 participants (14 male; mean [SD] age, 66 [7] years; FEV1% predicted, 32 [17]%; median [interquartile range] Medical Research Council dyspnea scale, 3.5 [3.0-4.3]) completed pulmonary rehabilitation. Peak oxygen uptake increased 1.1 (0.4-1.7) ml·min(-1)·kg(-1) (8%) from baseline (P<0.01). The mean (95% confidence interval) 6-minute-walk test distance improved by 72 (45-98) m (P=0.001). The change in the Chronic Respiratory Questionnaire total score of 1.6 (1.1-2.1; P<0.001) was achieved by improvement in all four domains above the clinically important difference. All the physiotherapists considered one-legged cycling safe and would continue to prescribe it; 75% of participants would recommend it to other patients., Conclusions: One-legged cycling was successfully implemented into a "real-life" pulmonary rehabilitation program, demonstrating improvements in cardiorespiratory fitness with associated improvement in function for patients with moderate/severe COPD. One-legged cycling should be recommended in professional pulmonary rehabilitation guidelines as an option for exercise training and be available in other pulmonary rehabilitation programs. Clinical trial registered with www.clinicaltrials.gov (NCT01930526).

Background: Cardiorespiratory fitness, assessed during cardiopulmonary exercise tests by peak oxygen uptake (Vo2pk), is an independent predictor of mortality in obesity. We investigated whether Vo2pk and systemic responses measured during field walking tests were similar to those measured during an incremental treadmill test (ITMT) in obese individuals with treated OSA., Methods: Individuals with treated OSA and a BMI > 30 kg/m2 were recruited. Participants completed an ITMT, two 6-min walk tests (6MWTs), and two incremental shuttle walk tests (ISWTs) on three separate days in a randomized order. Expired gas analysis was performed during all tests., Results: The study was completed by 16 patients (nine men) (mean [SD] age, 58 [12] y; BMI, 36.1 [7.6] kg/m2). There was no difference (P = .27) in Vo2pk assessed by the ITMT and the ISWT (2,266 [478] and 2,017 [561] mL/min, respectively). The Vo2pk measured by the 6MWT (1,778 [360] mL/min) was lower than that measured by the ITMT (P < .01). The limits of agreement for Vo2pk between the ISWT and the ITM were ± 730 mL/min. Cardiorespiratory responses during the ISWT and the ITMT reflected a graded response to a peak, whereas the 6MWT demonstrated a rapid rise to a plateau., Conclusions: The ISWT can be used instead of an ITMT and in preference to the 6MWT to assess cardiorespiratory fitness for a cohort of obese people with treated OSA. However, the imprecision of the agreement in Vo2pk between the ITMT and ISWT means they cannot be used interchangeably in an individual., Trial Registry: ClinicalTrials.gov; No.: NCT01930513; www.clinicaltrials.gov.

Background: Patients with chronic respiratory diseases often have the simple goal of wanting to walk for longer. We evaluated the properties of a patient goal-oriented, symptom-limited, self-paced walk (SPW)., Methods: Patients with symptomatic chronic respiratory disease, referred for a 6-week course of pulmonary rehabilitation (PR), were screened for eligibility. Baseline assessments included two SPWs with both time and speed measured, two 6-min walk tests (6MWTs), and the Medical Research Council dyspnea scale. On program completion, two SPWs and one 6MWT were performed. The repeatability, responsiveness, and validity of the SPW were assessed., Results: Two SPWs were completed by 50 and 37 patients before and after rehabilitation, respectively. The speed (r = -0.54, P < .001) but not the time (r = -0.23, P = .19) of the SPW correlated with Medical Research Council dyspnea grade. The mean SPW time increased on the second day of testing from 15.1 ± 8.4 min to 17.9 ± 7.7 min (P = .004), and the effect of test day was unaltered by PR (P = .80). The coefficient of repeatability for SPW time was 16.1 min. Both the mean SPW time (10.6 min; 95% CI, 6.6-14.5 min; P < .001) and the mean speed (3.5 m/min; 95% CI, 1.3-5.7 m/min; P < .01) increased after rehabilitation., Conclusions: The SPW time is an easily understandable, patient goal-oriented assessment with construct validity that is highly responsive to the effects of PR. The variability in SPW time makes it better suited to interpreting group rather than individual changes., Trial Registry: ClinicalTrials.gov; No.: NCT00781183; URL: www.clinicaltrials.gov.

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.

Background: The protocol used for the 6-min walk test (6MWT) influences its results. The only study to examine the effect of modifying track layout performed a retrospective analysis and concluded that institutions using continuous tracks yield greater distances than those using straight tracks. Agreement between the distances measured on different tracks could not be examined. We evaluated the effect of modifying track layout on walk distance and examined the agreement and repeatability of distances measured on different tracks., Methods: In a prospective, randomized, cross-over study, 27 COPD subjects (FEV(1), 38 +/- 14% [mean +/- SD]; 15 men) attended three separate test sessions, completing six 6MWTs. To familiarize all subjects with both tracks, the first two sessions comprised two 6MWTs on either a circular or straight track. During the final session, each subject was tested once on the straight and once on the circular track., Results: The distance walked on the circular track exceeded the straight track by 13 +/- 17 m (p < 0.001). The limit of agreement between tracks was 33 m. Coefficient of repeatability values when the test was completed on different days for the straight and circular tracks were 51 m and 65 m, respectively., Conclusions: When evaluating changes in 6-min walk distance in groups of patients, track layout should be standardized. However, the effect of modifying track layout on an individual's walking distance is small compared to their daily variability in walk distance. Therefore, standardizing track layout for any given individual may be inconsequential when evaluating the change in distances from tests performed on different days.

Background: Most patients with severe COPD are limited by dyspnea and are obliged to exercise at low intensity. Even those undergoing training do not usually have increased peak oxygen uptake (Vo2). One-legged exercise, at half the load of two-legged exercise, places the same metabolic demands on the targeted muscles but reduces the ventilatory load, enabling patients to increase work capacity. The purpose of this study was to determine whether one-legged exercise training would improve aerobic capacity compared with two-legged training in stable patients with COPD., Methods: Eighteen patients with COPD (mean FEV(1), 38 +/- 17% of predicted [+/- SD]) were randomized to two groups after completing an incremental exercise test. Both trained on a stationary cycle for 30 min, 3 d/wk, for 7 weeks. Two-legged trainers (n = 9) cycled continuously for 30 min, whereas one-legged trainers (n = 9) switched legs after 15 min. Intensity was set at the highest tolerated and increased with training., Results: Both groups increased their training intensity (p < 0.001) and total work (p < 0.001). After training, the change in peak Vo2 of the one-legged group (0.189 L/min; confidence interval [CI], 0.089 to 0.290 L/min; p < 0.001) was greater than that of the two-legged group (0.006 L/min; CI, - 0.095 to 0.106 L/min; p = 0.91). This was accompanied by greater peak ventilation (4.4 L/min; CI, 1.8 to 7.1 L/min; p < 0.01) and lower submaximal heart rate (p < 0.05) and ventilation (p < 0.05) in the one-legged trained group., Conclusion: Reducing the total metabolic demand by using one-legged training improved aerobic capacity compared with conventional two-legged training in patients with stable COPD.

Background: In patients with COPD, exercise intensity is often limited by the ventilatory system. We hypothesized that by exercising with a smaller muscle mass, ventilatory-limited patients would perform more high-intensity, muscle-specific work. The study objectives were as follows: (1) to determine the limitations of exercising with a smaller muscle mass, compared with conventional two-legged exercise; and (2) to determine the endurance time, using the same muscle-specific intensity, during one-legged vs two-legged exercise., Methods: Nine patients (mean +/- SD FEV1, 36 +/- 13% of predicted) completed incremental exercise, and nine other patients (mean FEV1, 42 +/- 16% of predicted) completed constant-power exercise. Nine healthy subjects (FEV1, 104 +/- 14% of predicted) completed both tests. All subjects completed tests using two-legged and one-legged pedaling., Results: Peak oxygen uptake (VO2peak) was similar during one-legged and two-legged incremental exercise among patients (difference, 0.03 L/min; 95% confidence interval [CI], -0.10 to 0.16 L/min; p = 0.60), as were ventilation and dyspnea scores. VO2peak was lower during one-legged vs two-legged exercise (-0.57 mL/min; 95% CI, -0.81 to -0.32 mL/min; p < 0.001) among healthy subjects with substantial ventilatory and heart rate reserve. Patients endured one-legged pedaling at a constant power longer than two-legged pedaling (16.97 min; 95% CI, 9.98 to 23.96 min; p < 0.001), resulting in greater work (12.48 kilojoules [kJ]; 95% CI, 2.58 to 22.39 kJ; p = 0.02). Healthy subjects completed similar work (-4.02 kJ; 95% CI, -18.59 to 10.55 kJ; p = 0.54) with one-legged vs two-legged pedaling., Conclusion: These observations demonstrate the effectiveness of using one-legged exercise at the same muscle-specific intensity in extending the duration of exercise among patients with COPD. This has important implications for training approaches designed to enhance exercise function among ventilatory-limited patients.

Background: Despite the wide-ranging benefits of pulmonary rehabilitation, conflicting results remain regarding whether people with COPD can improve their peak oxygen uptake (V˙O2peak) with aerobic training.Research Question: The goal of this study was to investigate the effect of aerobic training and exercise prescription on V˙O2peak in COPD.Study Design and Methods: A systematic review was performed by using MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, and Cochrane databases for all studies measuring V˙O2peak prior to and following supervised lower-limb aerobic training in COPD. A random effects meta-analysis limited to randomized controlled trials comparing aerobic training vs usual care was conducted. Other study designs were included in a secondary meta-analysis and meta-regression to investigate the influence of program and patient factors on outcome.Results: A total of 112 studies were included (participants, N = 3,484): 21 controlled trials (n = 489), of which 13 were randomized (n = 288) and 91 were uncontrolled (n = 2,995) studies. Meta-analysis found a moderate positive change in V˙O2peak (standardized mean difference, 0.52; 95% CI, 0.34-0.69) with the intervention. The change in V˙O2peak was positively associated with target duration of exercise session (P = .01) and, when studies > 1 year duration were excluded, greater total volume of exercise training (P = .01). Similarly, the change in V˙O2peak was greater for programs > 12 weeks compared with those 6 to 12 weeks when adjusted for age and sex. However, reported prescribed exercise intensity (P = .77), training modality (P > .35), and mode (P = .29) did not affect V˙O2peak. Cohorts with more severe airflow obstruction exhibited smaller improvements in V˙O2peak (P < .001).Interpretation: Overall, people with COPD achieved moderate improvements in V˙O2peak through supervised aerobic training. There is sufficient evidence to show that programs with greater total exercise volume, including duration of exercise session and program duration, are more effective. Reduced effects in severe disease suggest alternative aerobic training methods may be needed in this population.Clinical Trial Registration: PROSPERO; No.: CRD42018099300; URL: https://www.crd.york.ac.uk/prospero/. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the effect of upper extremity resistance training on dyspnea while performing activity of daily living (ADL) among patients with chronic obstructive pulmonary disorder (COPD). The study included 36 patients with COPD who were randomized to undergo either arm resistance training or a sham. Study authors found that resistance-based arm training improved arm function, arm exercise capacity and muscle strength. However, such exercise did not improve dyspnea during ADL.