Does increased physical activity in school affect children's executive function and aerobic fitness?

This study seeks to explore whether increased PA in school affects children's executive function and aerobic fitness. The "Active school" study was a 10-month randomized controlled trial. The sample included 449 children (10-11 years old) in five intervention and four control schools. The weekly interventions were 2×45 minutes physically active academic lessons, 5×10 minutes physically active breaks, and 5×10 minutes physically active homework. Aerobic fitness was measured using a 10-minute interval running test. Executive function was tested using four cognitive tests (Stroop, verbal fluency, digit span, and Trail Making). A composite score for executive function was computed and used in analyses. Mixed ANCOVA repeated measures were performed to analyze changes in scores for aerobic fitness and executive function. Analysis showed a tendency for a time×group interaction on executive function, but the results were non-significant F(1, 344)=3.64, P=.057. There was no significant time×group interaction for aerobic fitness. Results indicate that increased physical activity in school might improve children's executive function, even without improvement in aerobic fitness, but a longer intervention period may be required to find significant effects.