Effect of exercise on the human gut microbiota in individuals with overweight and obesity: a systematic review and meta-analysis of randomized controlled trials.

Purpose: Obesity and its associated comorbidities, including chronic inflammation, pose significant public health challenges. Recent studies have suggested a link between obesity and gut microbial dysbiosis, with exercise emerging as a potential modulator of gut microbiota by enhancing microbial diversity and short-chain fatty acid (SCFA) production. However, the effects of exercise on the microbiome diversity and composition in overweight individuals or with obesity remain inconsistent.

Methods: This study systematically reviewed literature from PubMed, Embase, Cochrane Library, and ScienceDirect databases up to November 5, 2024, following PRISMA guidelines. Eleven studies were included in the systematic review, and four studies with quantitative data were analyzed using meta-analysis (Comprehensive Meta-Analysis software) and the ROB tool.

Results: The meta-analysis showed a statistically significant effect of exercise on beta diversity. The pooled effect size for Bray-Curtis dissimilarity was 4.56 (95% confidence interval (CI) [1.77, 11.80], Z = 3.14, P = 0.002). These findings suggest that exercise positively influences gut microbial structure in overweight individuals or with obesity.

Conclusion: Exercise may be a key component of lifestyle modification to modulate the gut microbiota and improve metabolic health in overweight individuals or with obesity. Future studies should evaluate the independent effects of fitness improvement and weight loss on gut microbial composition by employing multi-omics and metabolic pathway analyses to develop personalized obesity management strategies.