Exploring the impact of physical education on secondary student BMI and aerobic capacity

Background: Physical education (PE) is an important component of school-based obesity prevention. Purpose: To explore the role of PE term length on changes in student body mass index (BMI) and aerobic capacity test performance. Significance: PE provides students with an outlet to engage in physical activity. Methods: A prospective cohort study included baseline and follow-up height and weight measurements of 2101 middle and high school students enrolled in traditional PE. The length of the PE term was 9, 18, or 36 weeks. In addition, a sub-sample of 619 high school students provided aerobic capacity data at baseline and follow-up. Trained PE teachers conducted all measurements during the first and last weeks of the PE term. Results: Overall, there was a significant decrease in BMI percentile from baseline to follow-up (p <.001) and a significant interaction between PE term length and grade level on BMI percentile change. Among those students enrolled in an 18-week course, high school students had a significantly greater decrease in BMI percentile than did middle school students. With regard to aerobic capacity there was significant improvement in test performance from baseline to follow-up (p <.001). Students enrolled in an 18-week or 36-week PE course displayed significant improvement in aerobic capacity (p < .001) whereas students in the 9-week course did not show improvement. Conclusion: This study suggests that an 18-week PE term provides optimal benefits in regard to BMI and aerobic capacity for secondary students.