Effect of physical exercise on body fat percentage and body mass index in postmenopausal women with overweight and obesity: A systematic review and meta-analysis of randomized controlled trials

The objective of this study is evaluate and conduct a meta-analysis on the impact of different exercise durations and modalities on body fat percentage (BFP, primary outcome) and body mass index (BMI, secondary outcome) in postmenopausal women with overweight and obesity. A systematic search of multiple databases was performed to identify randomized controlled trials (RCTs) assessing the effect of exercise interventions on BFP and BMI in postmenopausal women with overweight and obesity. The search included studies published through October 2024. Meta-analysis was conducted using RevMan 5.4 software to generate forest plots, funnel plots, and perform sensitivity and subgroup analyses. Seventeen RCTs involving 1,378 participants were included. The meta-analysis revealed that exercise interventions significantly reduced both BFP and BMI compared to control groups, with a more pronounced effect on BFP reduction [Mean difference(MD) = −2.45, 95% CI:(−3.31, −1.59), p < 0.00001], and a significant reduction in BMI [MD = −0.82, 95% CI: (−1.61, −0.04), p = 0.04].Subgroup analysis indicated that exercise duration (≤12 weeks vs >12 weeks) did not significantly influence BFP reduction (Chi² = 0.84, p = 0.36). However, combined aerobic and resistance training demonstrated superior effects on BFP compared to aerobic exercise alone [Mean difference = −3.76, 95% CI: (−4.27, −3.26), p = 0.005]. Exercise interventions are associated with improvements in BFP and BMI in postmenopausal women with overweight and obesity. Indirect subgroup comparisons suggest a potentially greater reduction in BFP with combined aerobic and resistance training than with aerobic training alone. However, given the substantial statistical heterogeneity (I2 = 96%) and methodological variability across trials, the precise clinical magnitude of these benefits remains uncertain, warranting cautious interpretation and further confirmation by high-quality comparative RCTs.