Effect of an Educational Program on Schoolchildren’s Energy Expenditure during Physical Education Classes

Abstract

OBJECTIVE: Physical activity is a means of prevention of noncommunicable diseases. The level of physical activity of children is decreasing in Brazil, and this can increase the risks of diseases associated with sedentary lifestyles and obesity. METHOD: This is a school-based randomized controlled trial which evaluated the impact of an educational intervention on children's physical activity level, energy expenditure, and teacher's behavior during physical education classes at public schools in Sao Paulo. The studied population comprised children attending the 1st and the 2nd grades of eight schools (three exposed and five unexposed to teacher training on a course in nutrition and physical activity). Outcomes were measured by direct observation, recorded by a VHS camera during physical education classes; data from 78 physical education classes were analyzed by the System for Observing Fitness Instruction Time - SOFIT. RESULTS: After intervention, results showed highly significant increases in children's physical activity level (walking, p < 0.001; vigorous activities (p < 0.001), and a decrease in the standing category (p < 0.001). It also showed a nonsignificant increase in mean energy expenditure of children (70.6% = 27.6Kcal), but the interaction's effect of group and time (intervention) was highly significant (32.4Kcal; 95%CI 24.7 - 40.1, p < 0.001) indicating the intervention effectiveness in increasing the energy expenditure of children during Physical Education classes. It also showed an increase in length of physical education classes (26.2 to 32.1 minutes (p = 0.01). CONCLUSION: There was a change in teachers' behavior with a positive impact on children's physical activity level and energy expenditure after the educational intervention.