Abstract

More and more often physical fitness research focuses on health - related fitness. One of the most important factors determining health - related fitness is body composition. The high level of fatness is considered to be a risk factor of many diseases. The aim of this paper was to characterize the differences in a level of the properties linked with health in children classified into different fatness level groups. The subjects were also divided according to sex and age. The study included 3233 children of 8 Poznarí primary schools (1659 boys and 1574 girls) aged 10 - 14. As a research tool we used a battery of "Eurofit tests", in particular, those elements that define health - related fitness. Fatness groups were established on the basis of centile level of the log sum of five skinfolds: the thin (up to 15 centiles), the average fat (from 25 to 75) and the obese (above 85 centile). The study results suggest that body fatness is a factor that significantly determines the level of all mentioned health related fitness properties except flexibility. Flexibility showed no statistically significant differences between the subjects with various fatness levels. The differences in static strength are usually but not in all groups of age statistically significant (a</=0,01) and the highest results were reached by obese children. Body fatness determines a functional strength level (a</=0,01), while the distincly lower results could be observed in obese children. The subjects with obesity also presented lower results for trunk strength and cardio - respiratory endurance (a</0,01). What is characteristic is the fact that for the two latter factors there were not found statistically significant differences between average fatness level subjects and the thin ones. Verf.-Referat