Effects of attending elevated level school physical education in 7 to 11-year-old boys.

The aim of the present longitudinal study of four years was to analyse differences in growth patterns, age-related changes in body fat and physical performance in schoolchildren taking part either in normal or in elevated level physical education at school.Nine data collection sessions were carried out between 2002 and 2006 in 18 schools. The sample consisted of 521 non-athletic volunteer boys (PE=116, contrast = 405).The inter-group differences between mean height, body weight, body mass index, relative body fat content, mean scores in 30 m dash, 400 m run, and standing long jump as well as the patterns of change with age were analysed in this comparison. Between-observation differences were tested by repeated measures ANOVA. In case of a significant F-test Tukey's post-hoc tests were used. Age dependence was also studied by linear regression analysis.The between-group differences in mean height were not significant, but the slope of height increase with age was significantly greater in the PE boys. The PE boys were significantly lighter through all the nine observations and the slope of age-related weight increase was statistically faster in the group of contrast subjects. Both the BMI means and percent body fat means were consistently and significantly greater in the contrast group and faster increases were found in the group of the less active boys. The mean physical performances of the PE boys were consistently and significantly better. Their slopes of increase were statistically different.