Physical activity during PE lesson and after-school hours: Are they associated with children daily physical activity?

Introduction: School-based physical activity (PA), including PE and after-school sport class are possible occasions to increase children daily PA. Recent studies, however, questioned if increasing activity during the school hours may in return compensate children to be less active outside of school. The purpose of this study was to examine the association of school-based PA (i.e., PE class and after-school sport class) in different intensity (i.e., MPVA and sedentary) within various periods (i.e., in school hours and whole day). Methods: Participants were 212 children with mean age of 8.9 from four local primary schools in Hong Kong. Children’s PA level was measured by accelerometer (ActiGraph GT3X) for four consecutive days. Participants reported if they had scheduled PE lesson or participated in after-school sport class on the measurement period. The accelerometer counts derived into the time (min) of MVPA and sedentary behavior using age-specified criteria. Participants were grouped into 1) with PE lesson (PE group); 2) with after-school sport class (AFS group); or 3) no PE or after-school sport class (N-Act group). ANVOA was conducted to examine if children’s MVPA and sedentary behavior is a function of the participation of PE lesson or after-school sport class. Results: Excluding the non-school days data, 514 measurements were entered for analysis. Overall, children school-based MVPA during after-school hours (12.0 min) were higher than in PE lesson (8.6 min). Children daily MVPA was statistically significantly different between groups with various school-based PA participation [F(2,125) = 14.6, p < .000)] and increased from N-Act group (37.9 min) to PE group (46.1 min) and AFS group (59.5 min). For the sedentary behavior, significant difference was found between groups with various school-based PA participation [F(2,511) = 3.4, p = .03)] and decreased from N-Act activity (1190 min) to PE group (1173 min) and the AFS group (1151 min). Discussion: The present study added information on the understanding of children school-based PA participation. First, children’s participation in school-based PA was associated with their daily MVPA level, in which children with after-school participation were engaged in higher daily MVPA than their counterparts. The importance of after-school hours and PE class to increase children’s PA participation is further confirmed. Second, children daily sedentary behavior was significantly decrease in the group with PE and after-school sport class participation. The involvement in PA during school hours, therefore, may not result in lower daily PA. On the contrary, is possible to enhance the lifestyle PA of children. References: Trost, S.G., Rosenkranz, R.R. & Dzewaltowski, D. (2008). Med Sci Sport Exer, 40 (4), 622-629. Slingerland, M. & Borghouts, L. (2011). J Phys Act Health, 8, 866-878.