The effects of exercise interventions on weight regain after weight loss: a systematic review and meta-analysis.

To systematically evaluate the effects of exercise during the post-weight-loss maintenance phase on weight regain. This study was registered in PROSPERO (CRD420251240526) and reported in accordance with the PRISMA statement. We searched PubMed, Embase, Web of Science, the Cochrane Library, and CNKI from database inception to October 19, 2025. Randomized controlled trials investigating exercise interventions during the weight-maintenance phase after successful weight loss in individuals with overweight/obesity were included. Risk of bias was assessed using the revised Cochrane Risk of Bias tool for randomized trials, RoB 2.0. Eleven trials involving 568 participants were included. Meta-analysis showed that the exercise group experienced significantly less weight regain than the control group (MD = - 2.81 kg, 95% CI: -5.12 to - 0.51; I² = 0%). Evidence for fat-mass reduction remained inconclusive because the primary random-effects analysis was non-significant and substantial heterogeneity was present (MD = - 3.39 kg, 95% CI: -7.24 to 0.46; I² = 69%). Exercise confer a small but consistent benefit for weight maintenance after weight loss; however, evidence for improvements in fat mass remains inconclusive. Further trials with longer follow-up, standardized exercise prescriptions, objective adherence monitoring, and harmonized body-composition assessment are warranted.