Influence of age, percentage of fat, abdominal endurance in cardiorrespiratory fitness of adolescent schools: A path analysis

Objective: To investigate the direct and indirect association of variables age, percentage of fat, abdominal muscle endurance and mean arterial pressure with cardiorespiratory fitness (CRF). Methods: Adolescent schoolchildren from municipal public schools, aged from 11 to 14 years, from Montes Claros (MG), were researched. Cardiorespiratory fitness was assessed by the sixminute running test, the percentage of fat was assessed by the sum of skin folds, muscle endurance was assessed by sit up test, and systemic blood pressure was represented by mean arterial pressure. Multivariate analysis was performed using path analysis. Results: 860 students participated, 52.9% of whom were female. There was a direct negative effect of female age and percentage of fat on cardiorespiratory fitness, in addition to the direct and positive effect of abdominal endurance in both sexes. There was also an indirect effect of the percentage of fat on cardiorespiratory fitness mediated by abdominal endurance. The proportion of direct effect in relation to total effect of fat percentage on cardiorespiratory fitness was 95.4% in girls and 96.7% in boys. Conclusions: Considering the effect of age, percentage of fat and muscle endurance on cardiorespiratory fitness, it is suggested to promote actions that encourage practice of physical exercises from earlier ages.