METHODS: A computerized literature search using Medline (Ovid) and Scopus were conducted to identify relevant observational studies on the influence of different level of PA on bone acquisition among the healthy adolescent population. All articles included, were limited to original articles and English language.

RESULTS: Nine studies met the inclusion criteria. Reported bone outcomes were of bone mass, bone structure and bone strength. Eight studies showed positive association between adolescents' PA and high bone variables. The influence of PA may differ according to sex, skeletal sites and bone outcomes.