Cardiorespiratory fitness and health‐related quality of life in adolescents: A longitudinal analysis from the LabMed Physical Activity Study

Objective The purpose of this study was to examine the longitudinal associations between cardiorespiratory fitness and health‐related quality of life (HRQoL) in a sample of adolescents, and to determine whether changes in cardiorespiratory fitness were associated with HRQoL over a 2‐year follow‐up. Methods This is a longitudinal analysis with 571 Portuguese adolescents (274 boys and 297 girls) aged 12‐18 years. HRQoL was measured with the Kidscreen‐10 questionnaire; the 20 m shuttle‐run was used to estimate cardiorespiratory fitness; socioeconomic status was assessed with the Family Affluence Scale; and pubertal stage was assessed with Tanner stages. Linear regression and analysis of covariance (ancovas) were used to examine the associations between cardiorespiratory fitness and HRQoL. Results HRQoL decreased over a 2‐year period both in boys and girls (P