Changes in obesity, sedentary behavior and physical inactivity, between 2010 and 2017, in adolescents

Abstract

The study investigated changes in the prevalence of obesity, sedentary behavior (SB) and physical inactivity (PI) in adolescents. Two cross-sectional studies were analyzed, 2010 and 2017, with probabilistic samples from students (328 and 366, respectively) in 12 municipal schools in Niterói, RJ. Obesity was classified based on body mass index (BMI = weight / height²) Z score values ≥ +2, according to the World Health Organization criteria. The weight classification was made with body mass index (BMI = weight/height²), the SB for those with some screen behavior (television, video game) for ≥ 2 hours/day and IF those who performed <300 min / week moderate to intense physical activity. The comparison between the studies was based on the chi-square test (categorical variables) and Student's t test (continuous variables). The prevalence of obesity increased in boys (6.2% to 15.6% p <0.001) and decreased in girls (8.4% to 6.9% p = 0.035). The frequency of SB decreased from (90.7% to 67.7% p <0.001) in boys and from (90.3 to 52.8% p <0.001) in girls and the PI did not change in boys and increased in girls (84.6% to 89.9% p <0.001). The changes observed were sex-dependent, with boys more vulnerable to increased obesity, girls more PI and both sexes less SB in the investigated period.