[Effects of exercise on bone mineral content in children and adolescents at different growth stages: a Meta-analysis]

To evaluate the effect of exercise on bone mineral content(BMC) in children and adolescents at different growth stages.

EMBASE, PubMed, Web of Science, CNKI, VIP database and Wanfang database were searched. The randomized controlled trials(RCTS) published in Chinese and English on the effects of exercise on BMC in children and adolescents were collected using exercise, children, adolescents and BMC as search terms. Cochrane collaboration tool was used to evaluate the quality of the included studies, and RevMan5.4 software was used for Meta-analysis. The search time limit is from the establishment of the database to July 20, 2022.

A total of 18 articles(22 RCTS) involving 1305 children and adolescents were included. The result of the Meta-analysis showed that: Compared with the control group, (1) exercise significantly improved spinal BMC(SMD=0.28, 95%CI 0.17-0.40, P<0.01) and femoral neck BMC(SMD=0.40, 95%CI 0.20-0.61, P<0.01), but not for systemic BMC(SMD=0.08, 95%CI-0.04-0.21, P=0.19). (2) Subgroup analysis showed that exercise significantly improved spinal BMC in the following stages: prepubertal(SMD=0.48, 95%CI 0.27-0.69, P<0.01)and early pubertal(SMD=0.22, 95%CI 0.05-0.39, P=0.01). The stages in which exercise significantly improved femoral neck BMC were as follows: prepubertal(SMD=0.60, 95%CI 0.05-1.16, P=0.03), early pubertal(SMD=0.22, 95%CI 0.01-0.43, P=0.04), middle and late pubertal(SMD=0.43, 95%CI 0.13-0.72, P<0.01).

Exercise significantly enhanced spinal BMC during preadolescence and early adolescence as well as femoral neck BMC throughout childhood and adolescence, especially with higher effect sizes during preadolescence.