Efeito da intensidade do exercício físico no gasto energético com atividades físicas em meninos com excesso de peso.

Abstract

Epidemiological studies have shown rapid increase in the prevalence of overweight and obesity, both in adults and in children and adolescents and physical exercise considered an important strategy in the prevention and in the treatment of weight gain. Nevertheless, studies evaluating the isolated effects of exercise on weight control have shown conflicting results. These findings can be explained by a possible compensatory effect caused by exercise session in physical activities in subsequent periods. Therefore, the aim of this study is to evaluate the effect of different exercise intensities in energy expenditure with physical activity in adolescents with overweight. The study design was a crossover design with three sessions (control, moderate exercise and vigorous exercise). Twenty-four teenagers 11-13 years old, students from public schools in Niterói, Rio de Janeiro, male and overweight agreed to participate. The energy spent on physical activity was assessed by triaxial accelerometers placed during the experimental sessions and removed after six days. The data relating to energy expenditure associated with physical activity were assessed in 1st hour of using the accelerometer and during the six days of monitoring. In addition, values were also treated cumulatively, it has been calculated total energy expenditure of 24, 48, 72, 96, 120 and 144 hours. Analysis of variance was used to evaluate the possible differences between the energy expenditure in the first hour of registration between the three groups then the post hoc Scheffé. A comparison of the mean changes in energy expenditure (per day cumulative) was performed by mixed linear model. Comparison of energy expenditure during the 1st time showed significant differences between all three groups, with averages of 82, 286 and 343 kcal to the control group, moderate and intense, respectively (p <0.001). The same pattern of difference in energy expenditure between the groups remained after 24 hours (704 vs 970 vs 1056 kcal, p <0.001) and the cumulative energy expenditure during the six days of monitoring (5102 vs 5193 vs 5271 kcal, p <0.001). The analysis of energy expenditure per day demonstrated a reduction in energy expenditure of moderate and vigorous groups from the second day and remained until the sixth day of monitoring. Thus, we can conclude that a single aerobic workout seems to modify the behavior of spontaneous physical activities over 6 days in adolescents with overweight. However, despite the observed compensatory effect, the cumulative energy expenditure during the six days for the groups that carried out the exercise sessions was higher than the control session, with the vigorous group presented the highest accumulated expenditure for the follow-up period. Future studies are needed to investigate the compensation of energy expenditure in obese and nonobese patients and the effect of a greater number of training sessions.