Effects of different exercise training modalities on clinical and physical fitness outcomes in patients with obstructive sleep apnea: a systematic review and Bayesian meta-analysis

Abstract Background Exercise training has increasingly been considered a potential adjunctive strategy for the management of obstructive sleep apnea, yet the extent to which different exercise modalities improve disease severity, symptoms, and cardiorespiratory fitness remains uncertain. Exercise-related improvements may not be driven solely by mechanisms related to body mass index, challenging the assumption that symptom relief is primarily weight dependent. This systematic review and Bayesian meta-analysis primarily evaluated the effect of long-term exercise training on the apnea–hypopnea index (AHI), while also examining modality-specific effects, secondary clinical and physical fitness outcomes, and baseline body mass index as a potential moderator. Methods Five electronic databases and one electronic data platform, EBSCO, were searched from inception to April 29, 2026, with all 9 EBSCO-hosted databases searched simultaneously through a single integrated interface. Randomized controlled trials enrolling adults with obstructive sleep apnea and evaluating structured exercise interventions lasting at least 4 weeks were included. The primary outcome was the apnea–hypopnea index. Secondary outcomes included oxygen desaturation index, Epworth Sleepiness Scale score, body mass index, neck circumference, maximal oxygen uptake, and peak oxygen uptake. Bayesian random-effects models were fitted, and effects were summarized as posterior medians with 95% credible intervals. Results Thirteen randomized controlled trials involving 609 participants were included. Exercise training produced a clinically meaningful improvement in apnea–hypopnea index, with an original-direction MD of − 5.31 events/h, corresponding to a benefit-oriented MD of 5.31 events/h (95% credible interval, 3.09 to 7.92). Modality-specific estimates were imprecise: the 95% credible intervals for aerobic training and high-intensity interval training crossed zero, and no superiority among exercise modalities was established. Consistent benefits were observed for Epworth Sleepiness Scale score (mean difference, 2.33; 95% credible interval, 0.97 to 3.78) and peak oxygen uptake (Hedges’ g, 0.63; 95% credible interval, 0.31 to 0.95). Oxygen desaturation index also improved, whereas maximal oxygen uptake and neck circumference showed favorable but less certain estimates. Exercise yielded modest, albeit uncertain, reductions in BMI. Together with weak evidence for baseline BMI as a moderator, these findings are consistent with mechanisms extending beyond changes in BMI; however, individual-level mediation analyses are needed. Conclusions Long-term exercise training appears to improve obstructive sleep apnea severity and related clinical outcomes. However, modality-specific evidence remains uncertain and does not establish that one exercise type is more effective than another. Exercise training may be considered as an adjunctive strategy, with the choice of modality guided by patient preferences, safety, feasibility, and the likelihood of adherence.