Intervention
The ScIM project had three study arms, with a two-arm intervention designed to increase physical activity by 120 minutes each school week. Both intervention arms involved extra 60 minutes of physical education and 60 minutes of physical activity, in addition to the standard classes of physical education (120–180 minutes per week). Since we aimed to examine school-based physical activity, rather than the specific attributes of the intervention components, we combined both intervention arms into a single group, hereby referred to as the intervention group. Detailed information about the intervention components for the two interventions, teachers training, and material used, has been presented elsewhere [During the intervention period, a teacher reported intervention adherence every week at each school through a website designed at the Norwegian School of Sport Sciences. The intervention schools completed on average 80% of the intended dose of physical activity through the intervention period. The CONSORT and the TIDieR checklist are attached as 