EXERCISE

Study Design Systematic review and meta-analysis. Background It remains unclear whether exercise combining different types of physical activities (combined exercise interventions) would effectively preserve postmenopausal women's bone mineral density (BMD) at different sites. Objectives To examine the impact of combined exercise interventions on lumbar spine, femoral neck, total hip and total body BMD in postmenopausal women. Methods An electronic database search was conducted in PubMed, EMBASE, SPORTDiscus, and Web of Science up to Jan1, 2016. Randomized controlled trials (RCTs) that conducted combined exercise interventions and reported BMD values in postmenopausal women were included. Two authors independently extracted the data from individual studies. The primary endpoint was the change in BMD values from baseline to follow-up. The effect sizes were estimated by the standardized mean difference (SMD) methods using fixed-effects models. Results Eleven RCTs including 1061 postmenopausal women met the inclusion criteria. The levels of between-study heterogeneity were relatively low (I(2)<50%). Exercise integrating different physical activities significantly increased lumbar spine (SMD=0.170, 95%=0.027-0.313, p=0.019), femoral neck (SMD=0.177, 95%CI=0.030-0.324, p=0.018), total hip (SMD=0.198, 95%CI=0.037-0.3590, p=0.016) and total body (SMD=0.257, 95%CI=0.053-0.461, p=0.014) BMD. Combined exercise interventions generated a beneficial effect on femoral neck BMD (SMD=0.219, 95%CI=0.034-0.404, p=0.020) in groups with participants' age<60 years, and significantly improved lumbar spine BMD (SMD=0.349, 95%CI=0.064-0.634, p=0.016) in groups with women's age≥60 years. Conclusion Our findings suggest that combined exercise interventions appear to be effective in preserving postmenopausal women's BMD at lumbar spine, femoral neck, total hip and total body. Level of Evidence Therapy, level 1a. J Orthop Sports Phys Ther, Epub 3 Mar 2017. doi:10.2519/jospt.2017.6969.