Objectively measured differences in physical activity in five types of schoolyard area

Physical activity (PA) in childhood is related to a multitude of short- and long-term health consequences. School recess can contribute with up to 40% of the recommended 60. min of daily moderate-to-vigorous physical activity (MVPA). This paper aims to investigate how schoolchildren use different schoolyard areas during recess and whether these areas are associated with different levels of PA. Time spent by 316 students (grade 5-8) in five types of schoolyard area was measured during at least two days and four separate recess period per person (in total 1784 recess periods), using global positioning system (GPS) and the level of activity was measured using accelerometers. Total time spent and proportions of time spent sedentary and in MVPA were calculated per area type. Significant differences in PA levels were found. Grass and playground areas had the highest proportion of time in MVPA and solid surface areas had the highest proportion of time spent sedentary. Boys and children spent a higher proportion of time in MVPA. Girls accumulated more sedentary time in all area types compared to boys. This finding emphasizes the importance of investigating various settings and features in schoolyards in promoting PA. Grass and playground areas may play an important role in promoting PA in schoolyards, while a high proportion of time in solid surface areas is spent sedentary. In future, more detailed studies of the exact schoolyard setting using a combination of GPS, accelerometer and direct observation would be beneficial.