Physical fitness predicts adiposity longitudinal changes over childhood and adolescence

Objectives: The purpose of this study was to examine the influence of physical fitness (PF) on the development of subcutaneous adipose tissue in children followed longitudinally over a 9 year period ranging from childhood to adolescence. Design:This longitudinal study followed 518 healthy participants (262 boys, 256 girls) over a 9-year period ranging from childhood (age 6) to adolescence (age 15). Adiposity (triceps and subscapular skinfolds), and fitness (60 s sit-ups, flexed arm hang, standing long jump, 50 m dash, 10 m shuttle run, sit-and-reach, and 20 m pacer run) were assessed at four annual time points during primary school, and on a follow up, 6 years later, during secondary school. Methods: Growth in subcutaneous fat was modeled within a HLM statistical framework, using fitness components as time changing predictors. Results: Flexed arm hang (beta = -0.059; p = 0.000), standing long jump (beta = -0.072; p = 0.000), 60s sit-ups (beta = -0.041; p = 0.040), 50 m dash (beta = 0.956; p = 0.000), and 20 m PACER (beta = -0.077; p = 0.000) tests, were found to predict changes on body fat growth over the years, independently of sex. Conclusions: Improving PF individual levels can positively influence adiposity deposition over the time period covering childhood and adolescence. That occurs independently of the typical sex differentiated adiposity growth. (C) 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.