A comparative study found that a seven-year school-based exercise programme increased physical activity levels in both sexes

Aim: This study assessed whether a Swedish school-based exercise intervention programme could increase total physical activity. Methods: We followed up 228 children who started school in 1998-2000 seven years later, when they had reached a mean age of 14.8. The 152 children (59% boys) at the intervention school did 200 minutes of physical education per week during that period, and the 76 children (50% boys) in the three control schools did the standard 60 minutes. Questionnaires assessed the durations of total and leisure-time physical activity and screen-time activity at baseline and after five and seven years. Results: Physical activity and screen-time activity were similar between the two groups before the study started. The intervention group then achieved higher durations of total physical activity than the controls (p < 0.001) and these levels remained in the sex-specific evaluations. There were no differences between the groups in the durations of leisure-time activity (p 0.08-0.77) or screen-time activity (p 0.31-0.91). Conclusion: A school-based exercise intervention programme increased the total duration of physical activity in both sexes without any compensatory increase in screen-time activity. The findings contradict the activity-stat theory, which stated that the duration of physical activity in children is constant.