Young children's energy expenditure and moderate-to-vigorous physical activity on weekdays and weekends

Background: Few studies have examined young children's leisure- and school-based energy expenditure (EE) and moderateto-vigorous physical activity (MVPA). The purpose of this study was to explore children's estimated EE rates and time spent in MVPA in 3 time segments: at-school, after-school, and weekends. Methods: A total of 187 second and third grade children from 2 elementary schools participated in the study. Accelerometers were used to assess children's 5-day EE and MVPA. Multiple 2 (Grade) × 2 (Gender) ANOVAs with repeated measures (Time) were conducted to examine the differences in the outcome variables. Results: Significant time effects on EE and MVPA were revealed. Children's EE rate and minutes in MVPA per day were higher during after school and weekends than at school. Conclusions: Although children were more active outside of school, their MVPA during weekdays and weekends still fell far short of the recommended level of 60 minutes/day.