Young Adolescents’ Physical Activity In Five Locations As Measured Using GPS And Accelerometry

PURPOSE: To identify youths’ physical activity (PA) in 5 locations and investigate differences by participant factors. METHODS: 616 youth (14.2±1.5 years old; 49.2% girls; 31.6% non-White; 11.2% obese) were recruited from 311 census block groups in the Baltimore, MD and Seattle, WA regions. Participants wore an accelerometer and GPS tracking device for 7±2.6 days. GIS was used to classify GPS points as (1) at home (50 meter radial buffer), (2) at school (15 meter parcel buffer), (3) near home and (4) near school (both 1 kilometer street network buffers), and (5) at all other locations. Accelerometer and GPS data were time-matched and moderate to vigorous PA (MVPA) in each location was assessed using Evenson cut points. Mixed-effects regression tested differences in MVPA minutes in each location by gender, race/ethnicity, and obesity status. RESULTS: Mean daily minutes of MVPA was 38.0±28.1 overall, 7.4±14.1 at home, 11.3±18.2 at school, 5.5±13.7 near home, 2.7±9.5 near school, and 11.7±21.6 at other locations. 5.2±11.9% of time at home, 5.3±7.4% of time at school, 8.6±15.1% of time near home, 9.8±17.7% of time near school, and 6.2±11.5% of time at other locations was spent in MVPA. Boys had 22-56% more MVPA minutes than girls in all locations except near school (Fig 1). Non-White’s had 24-42% more MVPA minutes near home and near school than White non-Hispanics. Normal/overweight youth had 40-56% more MVPA minutes near home and at other locations than obese youth. CONCLUSION: Understanding where PA occurs can provide insight into creating more supportive environments for youth PA. Schools and other locations contributed the most to youths’ overall PA, but these locations were contributors to gender disparities. The low amount of neighborhood PA suggests need and potential for increasing youths’ PA and reducing obesity through interventions to support active travel.