Exercises improve body composition, cardiovascular risk factors and bone mineral density for menopausal women: A systematic review and meta-analysis of randomized controlled trials

Menopause has been considered as an aggravating factor for developing cardiovascular diseases and the metabolic syndromes for women. Exercise might be an effective intervention for reducing such threats. The purpose of this study was to evaluate the exercise effects on body composition, cardiovascular risk factors, and bone mineral density of menopausal women. Two reviewers did a complete search of five electronic database (Medline, PubMed, Cochrane Central Register of Controlled Trials, CINAHL, and the Chinese Electronic Periodical Service) records up to January 31, 2014. Randomized controlled trials (RCTs) that compared female menopausal participants with exercises, and those without exercise or with placebo were included. Risk of bias was classified based on the Cochrane Collaboration tool, the meta-analysis was conducted using Comprehensive Meta-Analysis Version 2.2. The study selection, data extraction, and validation were performed independently by the 2 reviewers. A total of 17 RCTs with 792 participants were included for meta-analysis. Among the eight RCTs (247 participants), a moderate effect size of exercise on body fat was found (SMD = − 0.34, 95% CI: − 0.60 to − 0.08). In five RCTs (195 participants), a moderate effect size of exercise on waist circumference (SMD = − 0.39, 95% CI: − 0.68 to − 0.09), in seven RCTs (162 participants), a moderate effect size on triglyceride level (SMD = − 0.37, 95% CI: − 0.62 to − 0.11), and in five RCTs (311 participants), a moderate effect size on bone mineral density (SMD = 0.38, 95% CI: 0.08–0.68). Subgroup analysis revealed a significant effect of aerobic exercise on body fat (SMD = − 0.29, 95% CI: − 0.53 to − 0.06), and a short-term exercise on body fat (SMD = − 0.50, 95% CI: − 0.89 to − 0.11) and on triglycerides (SMD = − 0.42, 95% CI: − 0.79 to − 0.04). The trials included in this meta-analysis were small and some had methodologic limitations. This study provides evidences to clinical practice for menopause women that exercise, compared with nonexercise or placebo exerted significant benefits on body fat, waist circumference, triglyceride level, and lumbar spine bone mineral density. Particularly, aerobic exercise did help menopausal women improve their body fat. A short-term exercise intervention had a benefit on not only body fat but also triglyceride level. However, well-designed, well-executed RCTs, and a detailed long-term clinical research should be needed in the future.