Aims Worldwide levels of daily physical activity (PA) in children are low. This has negative health consequences. Schools have been recognised as key settings to promote PA. This study evaluates the effectiveness of the playground programme PLAYgrounds on increasing PA.

Methods PLAYgrounds was evaluated by a controlled trial, with a follow-up during one school year (10 months). Accelerometer data were collected on 1500 children in total, divided over 19 sampling moments (every 2 weeks). SOPLAY data were collected at nine sampling moments (once a month). Four intervention and four control schools were matched for playground size, number of pupils and PA levels at baseline. The intervention consisted of restructuring the playground by playground markings and by encouragement of the active use of the playground, through the provision of play equipment and educational measures such as adult encouragement and supporting physical education classes. Multilevel regression analyses were performed to analyse the effects of the intervention.

Results PA levels in the intervention group (moderate PA) were significantly different (p<0.001) from the control group (light PA). During the intervention on an average 77.3% of the children engaged in moderate-to-vigorous physical activity in the intervention group and 38.7% in the control group. The effect of the intervention was significantly stronger for girls than for boys (p<0.001).

Conclusions The PLAYgrounds programme was effective in increasing PA levels in children during recess over the course of one school year. Thus, the programme could be used to provide structured PA promotion.