Exercise to improve pediatric bone and fat: a systematic review and meta-analysis

Abstract

Purpose: To determine the effects of school-based, bone-focused exercise interventions on bone, fat and lean mass in children by systematically reviewing and meta-analyzing the literature. Methods: Potentially relevant papers were identified by searching electronic databases. Abstracts were included if they described the effects of an in-school exercise intervention for children 5-17 years old compared with controls, and presented baseline and follow up results for bone, fat and lean measures. Identified studies were systematically reviewed for methodological quality. Meta-analyses were performed for whole body (WB), lumbar spine (LS) and femoral neck (FN) BMC (bone mineral content), fat and lean mass. Results: Sixteen eligible trials were identified including eight RCTs, three CCTs and five non-randomized, non-matched studies. The quality analysis revealed two studies had low, nine had medium and five had a high risk of bias. Meta-analyses revealed a small positive effect of bone-targeted exercise on WB BMC (standardized mean difference [SMD] of 0.483, 95% CI 0.132 to 0.833), FN BMC (SMD=0.292, 95% CI -0.022 to 0.607), LS BMC (SMD = 0.384, 95% CI 0.193 to 0.575), fat mass (SMD= -0.248, 95% CI -0.406 to -0.089), and lean mass (SMD= 0.159, 95% CI -0.076 to 0.394). Conclusion: Beneficial effects of school-based, bone-targeted exercise were observed for bone and fat, but not for lean mass. Excluding trials with high risk of bias strengthened that effect. Considerable study heterogeneity may have obscured effects on lean mass. The effects observed for bone and fat support the pursuit of brief, jumping-focused interventions to reduce fat as well as enhance musculoskeletal tissue in school age children.