Physiological responses and adaptations to exercise training in people with or without chronic obstructive pulmonary disease: protocol for a systematic review and meta-analysis

Introduction Exercise training is a cornerstone in managing chronic obstructive pulmonary disease (COPD), leading to several physiological adaptations including, but not limited to, structural and muscular alterations, increased exercise capacity and improved cognitive function. Still, it is not uncommon that the acute physiological response to an exercise session and the extent of chronic adaptations to exercise training are altered compared with people without COPD. To date, potential differences in acute physiological responses and chronic adaptations in people with or without COPD are not fully understood, and results from individual studies are contradictory. Therefore, the current study aims to synthesise and compare the acute physiological responses and chronic adaptations to exercise training in people with COPD compared with people without COPD. Methods and analyses A systematic review of randomised controlled trials (RCTs), non-randomised studies of interventions (NRSIs) and cross-sectional studies (CSSs) will be conducted. A comprehensive search strategy will identify relevant studies from MEDLINE, Scopus, CINAHL, SPORTDiscus, CENTRAL and Cochrane Airways Trials Register databases. Studies including adults with and without COPD will be considered. Outcomes will include cardiorespiratory, muscular and cognitive function, intramuscular adaptations, lung volumes and cardiometabolic responses. The protocol is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols and the Cochrane Methodological Expectations of Cochrane Intervention Reviews. Risk of bias assessment will be conducted using Cochrane Risk-of-Bias 2 Tool (for RCTs), Risk-of-Bias in Non-Randomised Studies Tool (for NRSIs) and Downs and Black checklist (for CSS). Meta-analyses will be conducted when appropriate, supplemented with a systematic synthesis without meta-analysis. Ethics and dissemination As this study is a systematic review, ethical approval is not required. The final review results will be submitted for publication in a peer-reviewed journal and presented at international conferences. PROSPERO registration number CRD42022307577