Associations of sedentary behavior, physical activity, and muscle strength with depressive symptoms in students from the Central-West Region of Brazil

Depression in children and adolescents can be related to lifestyle and constitutes a significant public health problem. This study aimed to evaluate the association between sedentary screen time, physical activity, and muscle strength with depressive symptoms in students aged 6 to 18 years from a region in the Midwest of Brazil. In this cross-sectional study, depressive symptoms were assessed using the Children’s Depression Inventory; physical activity, exercise/sports, and sedentary behavior were assessed using the National School Health Survey and the Low Back Pain and Body Posture Assessment Instrument; and muscle strength was measured using manual, scapular, and lumbar dynamometry, normalized by body weight. Prevalence ratios were estimated by Poisson regression with robust variance, stratified by sex. Among the 741 participating students, 17.3% presented depressive symptoms. In the adjusted analysis (PRadj), among girls, a higher prevalence of depressive symptoms was observed in those who watched TV for more than 4 h/day (PRadj, 2.46; IC95%: 1.20–5.04). Among boys, this association was found in those who used a computer for more than 4 h/day (PRadj, 2.38; IC95%: 1.04–5.45), spent more than 3 h/day in sedentary activities with screens (PRadj, 3.76; IC95%: 1.21–11.70), have not engaged in physical activity in the last seven days (PRadj, 2.35; IC95%: 1.15–4.78) and exhibited low muscle strength in the right hand (PRadj, 2.05; IC95%: 1.07–3.95). Greater exposure to sedentary behavior and physical inactivity has been associated with depressive symptoms, reinforcing the importance of promoting active lifestyles in children and adolescents.