Padrões de comportamento sedentário e atividade física: o efeito combinado associado aos fatores de risco cardiovascular em adolescentes do sexo feminino

Abstract

Currently, the potential deleterious effect of sedentary behavior, independent of physical activity has been highlighted. However, the combination of sedentary behavior with physical activity can lead to behavioral patterns with unique effects and different health implications. Therefore, we aimed to identify habitual patterns of sedentary behavior and physical activity and the association with adiposity markers and cardiovascular risk factors in teenagers. This is a cross-sectional study that evaluated 405 female teenagers (14-19 years), from Viçosa-MG. Body weight, height and waist circumference were measured. Body mass index and waist-toheight ratio were calculated. Body composition was assessed by Dual Energy X-Ray Absortometry. Blood pressure (BP) was measured and blood samples were collected for total cholesterol (TC), low density lipoprotein (LDL), very low density lipoprotein (VLDL), high density lipoprotein (HDL), triglycerides (TG), glycemia and fasting insulin measurements. It was measured Homeostasis Model Assessment Insulin Resistance (HOMA-IR). A 24-hour activity diary was used to assess behaviors on a continuum of intensity. The screen time was evaluated. The objective measure of physical activity was performed using a pedometer. The teenager participation was voluntary and by signing the Terms of Consent and Assent. The study was approved by the Ethics Committee on Human Research. Data analysis was performed by the softwares IBM SPSS® and STATA® using descriptive, bivariate and multivariate statistics. The significance level of =0.05 was adopted. It was observed a high prevalence of overweight/obesity (23.7%), abdominal obesity (16.9%), altered systolic and/or diastolic BP (17.5%) and changes in TC (46.0%), HDL (31.8%), LDL (20.5%) and TG (16.2%) among teenagers. Most of them do not comply with sedentary behavior based on screen time (72.0%) and physical activity (83.1%) recommendations. It was observed a higher prevalence of overweight/obesity in teenagers with longer screen time (p<0.05). Clusters with low levels of physical activity, regardless of sedentary behavior, presented higher odds of overweight/obesity, abdominal obesity and altered BP (p<0.05). The replacement of sedentarytime or screen time by moderate to vigorous physical activity (MVPA) progressively reduced the chances of altered BP (p<0.05). Integrating behaviors into a continuum of intensity over a 24-hour period resulted in four patterns: Physically Active, Slightly Active, Soaring Sleep and Sedentary. The prevalence of overweight/obesity in the Sedentary pattern was higher than in the Physically Active. And the prevalence of altered BP was lower in the Physically Active (p<0.05). Adherence to none of the recommendations represented a greater chance of overweight/obesity and abdominal obesity (p<0.05). The results support the deleterious effects of sedentary behavior and the health benefits of MVPA, as well as the importance of light intensity physical activity (LPA) and total physical activity, in a combined and integrated way throughout the day. The accumulation of MVPA remains the desirable goal and is recommended to replace sedentary behavior. However, among teenagers with a sedentary pattern, the replacement of sedentary activities for LPA seems to be an interesting alternative for the body weight control and the beginning of the desired behavioral change, being a beneficial complement to MVPA.