Background: Physical Activity Across the Curriculum (PAAC) was a three-year cluster randomized controlled trial to promote physical activity and diminish increases in overweight and obesity in elementary school children.

Methods: Twenty-four elementary schools were cluster randomized to the Physical Activity Across the Curriculum intervention or served as control. All children in grades two and three were followed to grades four and five. Physical Activity Across the Curriculum promoted 90 min/wk of moderate to vigorous intensity physically active academic lessons delivered by classroom teachers. Body Mass Index was the primary outcome, daily Physical activity and academic achievement were secondary outcomes.

Results: The three-year change in Body Mass Index for Physical Activity Across the Curriculum was 2.0 ± 1.9 and control 1.9±1.9, respectively (NS). However, change in Body Mass Index from baseline to 3 years was significantly influenced by exposure to Physical Activity Across the Curriculum. Schools with ≥ 75 min of Physical Activity Across the Curriculum/wk showed significantly less increase in Body Mass Index at 3 years compared to schools that had b75 min of Physical Activity Across the Curriculum (1.8±1.8 vs. 2.4±2.0, p = 0.02). Physical Activity Across the Curriculum schools had significantly greater changes in daily Physical activity and academic achievement scores.

Conclusions: The Physical Activity Across the Curriculum approach may promote daily Physical activity and academic achievement in elementary school children. Additionally, 75 min of Physical Activity Across the Curriculum activities may attenuate increases in Body Mass Index.