Therapeutic validity and effectiveness of supervised physical exercise training on exercise capacity in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis

Objective: Our aim was to determine the effectiveness of supervised physical exercise training on exercise capacity in patients with chronic obstructive pulmonary disease taken into consideration indices such as therapeutic validity of interventions, methodological quality of studies, and exercise volume. Data resources: MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, CINAHL, and PEDro databases were searched from inception until 17 July 2015 for randomized controlled trials comparing the effect of supervised exercise training vs. usual care in patients with chronic obstructive pulmonary disease. The references of included studies and review articles were hand searched for additional references and key authors of included trials were crosschecked in PubMed for any missed references. Review methods: Two reviewers independently assessed therapeutic validity of exercise training and methodological quality of included studies. Overall effects were calculated using a random effects model. Results: A total of 13 studies involving 756 patients with chronic obstructive pulmonary disease were included. Significant differences in maximal exercise capacity (standardized mean difference 0.52, 95% CI 0.31 to 0.74) and endurance exercise capacity (standardized mean difference 0.73, 95% CI 0.50 to 0.96) in favor of physical exercise training were found. The volume of physical exercise per week, the total volume of physical exercise, or their associations did not significantly influence the effect of training. Conclusion: Effects of supervised physical exercise was not significantly altered by therapeutic validity. A combination of aerobic exercise and strength training was found to be more effective than strength training or endurance training alone in increasing the 6-minute walking distance.