Association of physical fitness and body mass index in youth.

AIM: The aim of this study was to establish physical fitness (PF) levels in a school population of 11-18-year-old students and analyse differences according to body mass index (BMI) status in overweight

METHODS: This is a cross-sectional study. The sample comprises 636 children and adolescents (mean age of 14.5+/-1.5 years), 288 boys (45.3%) and girls 347 (54.7%). Six tests from Fitness-gram battery were used as an objective measure of physical fitness. Overweight/ Obesity status was determined using age and sex adjusted cut-off points.

RESULTS: Both girls and boys with obesity performed a significantly reduced number of tests in healthy fitness zone suggesting a decrease of performances in strength and cardiovascular fitness, from normal weight status to overweight and from overweight to obesity. Boys and girls with obesity are likely to be Under HFZ than normal weight.

CONCLUSION: The results suggest that obese and overweight children have low PF level compared to normal weight peers. A large number of children with normal weight were identified as well as unfit. These data also showed that a low BMI level would significantly improve some PF component.