Comparative Rehabilitation Benefits of Water-Based Versus Land-Based Exercise in Patients with Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis.

Patients with chronic obstructive pulmonary disease (COPD) commonly experience impaired lung function, reduced exercise tolerance, and respiratory muscle weakness. Owing to the unique properties of the aquatic environment, water-based exercise may provide rehabilitation benefits that differ from those of traditional land-based exercise. Objective: This systematic review and meta-analysis aimed to compare the effects of water-based versus land-based exercise on lung function, exercise capacity, and respiratory muscle function in patients with COPD, thereby providing evidence to inform the optimization of pulmonary rehabilitation exercise modalities. Methods: PubMed, Web of Science, CNKI, and other databases were systematically searched to identify randomized controlled trials comparing water-based and land-based exercise interventions in adults with COPD. Primary outcomes included lung function (FEV1% predicted and FEV1/FVC), exercise capacity (six-minute walk distance, 6MWD), respiratory muscle strength (maximal inspiratory pressure (MIP]) and maximal expiratory pressure (MEP). Meta-analyses were performed using Stata 17.0. Results: A total of 14 RCTs were included. Meta-analysis showed that, compared with land-based exercise, water-based exercise significantly improved FEV1% predicted (WMD = 3.33, 95% CI: 0.02-6.64) and FEV1/FVC (WMD = 4.00, 95% CI: 1.27-6.73). Regarding exercise capacity, water-based exercise significantly increased 6MWD (WMD = 47.81 m, 95% CI: 20.19-75.44), with more pronounced improvements observed in short-term interventions (≤8 weeks). Respiratory muscle function analyses demonstrated significant improvements in MIP (WMD = 14.22 cmH2O, 95% CI: 7.75-20.69) and MEP (WMD = 14.40 cmH2O, 95% CI: 4.92-23.89). Conclusions: Compared with land-based exercise, water-based exercise demonstrates consistent advantages in improving exercise capacity and respiratory muscle function in patients with COPD and shows additional benefits for lung function indices. Therefore, water-based exercise may serve as a valuable adjunct to land-based training within pulmonary rehabilitation programs.