Predicting Maximal Aerobic Capacity based on Self-Reported Physical Activity Levels among Adolescents

Growing evidence has indicated a positive association between physical activity and cardiorespiratory fitness (i.e., maximal aerobic capacity or VO2 max). Limited evidence, however, is available among adolescents. This research aimed to predict VO2 max based on the physical activity level and estimate the discriminant capacity of the physical activity levels on the VO2 max status among adolescents. This research was a cross-sectional study in 141 adolescents (age 19±1 year old, 83% male). The VO2 max was assessed using the 1-mile run test. Physical activity was measured using the International Physical activity Questionnaire-Long Form. Multiple linear regression was conducted to predict the VO2 max using physical activity level data (in metabolic equivalent of tasks (Mets/week), sex, and body mass index (BMI). The discriminant capacity of the total and domain-specific physical activity in discriminating high and low VO2 max was estimated with the area under the curve (AUC). The Youden Index determined cut-off points, sensitivity, and specificity. Multiple regression analysis revealed a significant predicting equation of VO2 based on total physical activities, BMI, and sex. The equation explained a significant proportion of VO2 max variances. The total and domain-specific physical activity significantly discriminated low and high VO2 max status, while the highest AUC was based on total physical activity, followed by other physical activity domains. A cut-off of total physical activity levels for predicting the VO2 max was successfully generated, with high sensitivity and specificity. Adequate evidence, thus, supports the prediction of VO2 max based on self-reported physical activity levels among adolescents.