RESUMO
Background: The increase in overweight and the physical inactivity in children and adolescents in the last years have been causing constant concerns. The comprehension of the postural patterns contributes to the prevention of postural deviations that could predispose to future pain and disabilities. The aim of this study was to assess the association between posture, sex, body mass index (BMI), and physical activity to understand the relationship of these factors with the posture of adolescents. Methods: We evaluated 217 adolescents of both sexes between 11 and 15 years of age who were students in municipal schools in São Paulo. The posture was assessed by photogrammetry, Foot Posture Index, Flexicurve, and the Scoliometer®. Physical activity was evaluated by the Physical Activity Questionnaire for Children and Adolescent. Results: The group of adolescents with obesity presented a higher angle of lumbar lordosis and the overweight group showed greater anteriorization of the head when compared with the group with normal weight. The females presented greater head anteriorization, Q angle and lumbar lordosis, and the males presented greater projection of the trunk and body forward. The group with sedentary habits showed greater abduction of the scapulae. Conclusions: We concluded that BMI and sex had the highest relationship with the posture of adolescents. Further studies are needed to clarify the association between physical activity and posture. Our results may assist future studies and support preventive and therapeutic actions in the treatment of adolescents' postural changes.