Cardiorespiratory fitness and adiposity in overweight and nonoverweight 8-year-old school children

Aim. The objective of the present study was to determine relationship between cardiorespiratory fitness and body fatness in both nonoverweight and overweight 8-year-old school children. Methods. The study participants were a 245 healthy second-grade elementary school children aged 8.9 +/- 0.4 yrs (125 boys, 120 girls). Anthropometric data (height, body mass, waist circumference, five skinfold thickness) were collected and body fat percentage was calculated. Body Mass Index (BMI) sex- and age-specific cutoff points were used for overweight and obesity definition and children were placed in two groups: overweight/obese and nonoverweight. Aerobic fitness was assessed with the multistage shuttle-run fitness test. Subjects were grouped into high (upper two quintiles) and low (lower two quintiles) aerobic fitness based on age and sex distributions. Results. BMI, waist circumference, five skin-fold thicknesses and total body fat were lower in overweight and obese children with high aerobic fitness in comparison with youths at the same BMI category with low fitness level (P<0.01).The beneficial effect of high aerobic fitness was also presented in nonoverweight children (P<0.01). Finally, aerobic fitness was moderately correlated with total body fat in the whole group of subjects (r.=-0.48, P<0.01). Conclusions. Indicators of local and total adiposity were lower in overweight and obese children with high aerobic fitness. Being fit may reduce the hazards of obesity in population of 8-year-old school children.