Impacts of active school design on school-time sedentary behavior and physical activity: A pilot natural experiment

Background Children spend a significant portion of their days in sedentary behavior (SB) and on average fail to engage in adequate physical activity (PA). The school built environment may influence SB and PA, but research is limited. This natural experiment evaluated whether an elementary school designed to promote movement impacted students' school-time SB and PA. Methods Accelerometers measured SB and PA at pre and post time-points in an intervention group who moved to the new school (n = 21) and in a comparison group experiencing no school environmental change (n = 20). Difference-in-difference (DD) analysis examined SB and PA outcomes in these groups. Measures were also collected post-intervention from an independent, grade-matched group of students in the new school (n = 21). Results As expected, maturational increases in SB were observed. However, DD analysis estimated that the intervention attenuated increase in SB by 81.2 +/- 11.4 minutes/day (p<0.001), controlling for time in moderate to vigorous physical activity (MVPA). The intervention was also estimated to increase daily number of breaks from SB by 23.4 +/- 2.6 (p<.001) and to increase light physical activity (LPA) by 67.7 +/- 10.7 minutes/day (p<0.001). However, the intervention decreased MVPA by 10.3 +/- 2.3 minutes/day (p<0.001). Results of gradematched independent samples analysis were similar, with students in the new vs. old school spending 90.5 +/- 16.1 fewer minutes/day in SB, taking 21.1 +/- 2.7 more breaks from SB (p<0.001), and spending 64.5 +/- 14.8 more minutes in LPA (p<0.001), controlling for time in MVPA. Students in the new school spent 13.1 +/- 2.7 fewer minutes in MVPA (p<0.001) than their counterparts in the old school. Conclusions This pilot study found that active school design had beneficial effects on SB and LPA, but not on MVPA. Mixed results point to a need for active classroom design strategies to mitigate SB, and quick access from classrooms to areas permissive of high-intensity activities to promote MVPA. Integrating active design with programs/policies to promote PA may yield greatest impact on PA of all intensities.