ABSTRACT BACKGROUND:

Our aim was to analyze multilevel correlates of cardiorespiratory fitness (CRF) according to sex, nutritional status and maturity status among adolescents.

DESIGN AND SETTING:

Cross-sectional study conducted in public schools.

METHODS:

This was a cross-sectional study on 1,209 adolescents aged between 10 and 17 years. CRF was estimated from the 20-meter shuttle run test. Anthropometric data on body mass index and waist circumference were obtained. Somatic maturation was assessed from the peak height velocity. Questionnaires were used to evaluate socioeconomic variables (family income, parents' education level and number of siblings) and behavioral variables (physical activity, screen time and alcohol and tobacco consumption) among the parents and adolescents.

RESULTS:

Boys, adolescents with normal weight and on-time maturers presented greater CRF (P < 0.05). Concerning socioeconomic correlates, girls (tobacco smoking, alcohol consumption, physical activity and screen time), adolescents with normal weight (alcohol consumption, physical activity and screen time), and on-time maturers (alcohol consumption, physical activity during childhood and habitual physical activity) demonstrated higher numbers of behavioral correlates with CRF. Normal-weight adolescents presented a higher number of biological correlates (chronological age, age at peak height velocity and waist circumference).

CONCLUSIONS:

Different correlates were observed according to sex, nutritional status and somatic maturation status. However, habitual physical activity, waist circumference and chronological age seemed to be the strongest factors associated with cardiorespiratory fitness among adolescents.