Which exercise modality improves vascular function most in overweight or obese adults? A Bayesian network meta-analysis of randomized controlled trials

Background Exercise is recommended for adults with overweight or obesity, but the comparative vascular effects of different exercise modalities remain uncertain. Methods We conducted a systematic review and Bayesian network meta-analysis of randomized controlled trials enrolling adults with overweight or obesity. PubMed, Web of Science, the Cochrane Library, and EBSCO SPORTDiscus were searched from inception to 31 May 2025, supplemented by Google Scholar and reference screening. Eligible interventions lasted at least 4 weeks and were classified as continuous endurance training (CET), resistance training (RT), interval training (INT), combined aerobic-resistance training (CT), or hybrid/mixed-modality programs (HYB). The primary outcome was flow-mediated dilation (FMD); secondary outcomes were pulse wave velocity (PWV) and carotid intima-media thickness (CIMT). Risk of bias was assessed using RoB 2 and certainty using CINeMA. Results Fifty-one randomized trials (2,638 participants) were included. Exercise improved FMD (standardized mean difference [SMD], 0.99; 95% CI, 0.69 to 1.29), reduced PWV (SMD, -0.31; 95% CI, -0.44 to -0.18), and reduced CIMT (SMD, -0.20; 95% CI, -0.36 to -0.05). In descriptive treatment-versus-control rankings, HYB had the largest FMD estimate, INT had the largest PWV reduction, and CET/CT had the largest CIMT reductions; however, these rankings were imprecise and certainty was low. FMD showed substantial heterogeneity (I2 = 87.1%). Sensitivity analyses excluding high-risk-of-bias studies and specialized cardiac or renal populations did not materially change the direction of findings. Conclusions Exercise interventions are associated with favorable vascular changes in adults with overweight or obesity. Apparent modality-specific differences should be interpreted as exploratory rather than definitive because confidence in the evidence was low and several comparisons were sparse or heterogeneous. Systematic Review Registration https://www.crd.york.ac.uk/PROSPERO/ , identifier CRD420251066443.