Associação da atividade física, comportamento sedentário baseado em tempo de TV e hábitos alimentares com a imagem corporal em escolares brasileiros: dados da pesquisa nacional de saúde do escolar 2019

Abstract

In accordance with the World Health Organization, adolescence is a critical developmental period marked by rapid and significant transformations. This stage encompasses changes in physical, motor, cognitive, psychological, emotional, and social aspects, including complex biological changes such as increases in height and weight driven by maturation and growth processes. These physiological and psycho-emotional changes associated with puberty profoundly influence adolescents' body image (BI) perception. Factors such as physical activity (PA), sedentary behavior (SB), and eating habits (EH) play a crucial role in shaping this perception. This study aimed to analyze how body image (BI) indicators cluster and how physical activity (PA), sedentary behavior (SB) based on TV time, and eating habits (EH) are associated with BI clusters in Brazilian adolescents, using data from the National School Health Survey (PeNSE), 2019 edition. The study included 143,164 Brazilian adolescents aged 13 to 17 years. PA was measured in the leisure and school domains, while SB was assessed by daily TV viewing time. EH was analyzed based on the weekly frequency of fruit, vegetable, sweets, fast food, and soft drink consumption. All these variables were evaluated using structured questionnaires. Additionally, sociodemographic variables such as sex, age group, maternal education, and living with parents were used as adjustments. To identify BI clusters, Latent Class Analysis (LCA) was employed, and associations between the variables were explored through multinomial logistic regression models. Four BI classes were identified: (1) Negative Body Image; (2) Thin and Satisfied; (3) Satisfied and Apparently Normal; and (4) Positive Body Image. The results showed that adolescents who engaged in up to 300 minutes of weekly leisure PA were more likely to belong to the positive BI classes. Regular vegetable consumption was also associated with a more positive BI perception. On the other hand, no significant association was found between TV viewing time and BI classes, suggesting the need to consider other aspects of SB beyond TV time. Furthermore, excessive consumption of sweets and soft drinks was related to a more negative BI perception. It is concluded that promoting leisure PA and adopting healthy EH are essential for improving BI perception and preventing health issues in this population. The findings provide valuable support for the formulation of public policies and school programs that address adolescent health in an integrated and comprehensive manner.