Sedentary lifestyles in children continue to be an epidemic in the U.S. The 2008 Physical Activity Guidelines for Americans suggest that children should accumulate 60 minutes of physical activity per day, including aerobic, muscle building and bone strengthening exercises. Little attention, however, has been paid to the contributions of in-school physical activity to meeting this recommendation and to the intensity of children's physical activity. Therefore, the purpose of this study was to compare step count outputs and Moderate-to-Vigorous Physical Activity (MVPA) detected during school hours from six different Arizona elementary schools using the NL-1000 accelerometer (NL; New Lifestyles Inc., Lee's Summit, Missouri, USA) in 10-11 year old children.
Method
Two hundred and seventy-five fourth and fifth grade students (female=147, male=128) with mostly Caucasian or Hispanic backgrounds wore the NL-1000 for up to five school days (mean wear time =6.6 ± 0.2 hours day). A typical week for these children included a daily 20 minute lunch recess (a free play opportunity with little equipment or organization), an additional 15 minute recess (similar to lunch recess), and an average of 60 minutes of Physical Education (two 30 minute classes) that included an array of activities from balance beam to rope jumping.
Analysis/Results
Results: Boys averaged significantly more steps (5057) per day than girls (4143); t(1247) = 4.87, p < .01. Boys also averaged slightly more minutes (15.96) of MVPA per day than girls (11/13), p = 0.07. Children were also slightly more active on Physical Education days. PE day's increased daily steps by 13% and daily MVPA by 22%. ANOVA results showed no significant differences across ethnic/racial groups.
Conclusions
School day physical activity contributes far less to MVPA per day than expected. Schools have been identified as ideal intervention sites for increasing youth physical activity. These findings, however, suggest a need to increase opportunities for children to participate in more MVPA while at school. Increases in Physical Education time, semi-structured recess, and classroom activity opportunities may be viable solutions.