Water-based exercise in COPD with physical comorbidities: a randomised controlled trial.

Land-based exercise is often difficult for people with chronic obstructive pulmonary disease (COPD) who have coexisting obesity or musculoskeletal or neurological conditions. This randomised controlled trial aimed to determine the effectiveness of water-based exercise training in improving exercise capacity and quality of life compared to land-based exercise training and control (no exercise) in people with COPD and physical comorbidities. Participants referred to pulmonary rehabilitation were randomly allocated to a water-based exercise, land-based exercise or the control group. The two exercise groups trained for 8 weeks, completing three sessions per week. 45 out of 53 participants (mean ± SD age 72 ± 9 years; forced expiratory volume in 1 s 59 ± 15% predicted) completed the study. Compared to controls, water-based exercise training significantly increased 6-min walking distance, incremental and endurance shuttle walk distances, and improved Chronic Respiratory Disease Questionnaire (CRDQ) dyspnoea and fatigue. Compared to land-based exercise training, water-based exercise training significantly increased incremental shuttle walk distance (mean difference 39 m, 95% CI 5-72 m), endurance shuttle walk distance (mean difference 228 m, 95% CI 19-438 m) and improved CRDQ fatigue. Water-based exercise training was significantly more effective than land-based exercise training and control in increasing peak and endurance exercise capacity and improving aspects of quality of life in people with COPD and physical comorbidities.