Association of environment and policy characteristics on children's moderate-to-vigorous physical activity and time spent sedentary in afterschool programs

• Policy alone is ineffective in increasing MVPA levels of children attending ASPs.
• The size of used play space was associated with children's activity levels.
• Programmatic structure maybe effective in increasing MVPA levels of children's attending ASPs.

BackgroundAfterschool programs are an important setting in which to promote children's physical activity. This study examines the association of environmental and policy characteristics on the moderate-to-vigorous physical activity and sedentary behavior of children attending afterschool programs.MethodsA total of 1302 children attending 20 afterschool programs across South Carolina wore accelerometers (ActiGraph GT3X +) for up to 4 non-consecutive days. Policy-level characteristics were evaluated using the Healthy Afterschool Program Index-Physical Activity scale. Physical activity space was measured using a measuring wheel (indoor, ft2) and Geographical Information Systems software (outdoor, acres). The structure (free-play or organized) of activity opportunities was evaluated via direct observation. Time spent in moderate-to-vigorous physical activity and sedentary, both indoors and outdoors, was estimated using accelerometry.ResultsFor every 5000 ft2 of utilized indoor activity space an additional 2.4 and 3.3 min/day of sedentary behavior was observed among boys and girls, respectively. A higher ratio of free-play to organized play was associated with higher indoor sedentary behavior among boys and girls (3.9 min/day and 10.0 min/day, respectively). For every 1 acre of outdoor activity space used, an additional 2.7 min/day of moderate-to-vigorous physical activity was observed for boys. A higher free-play to organized play ratio was associated with higher outdoor moderate-to-vigorous physical activity for boys and girls (4.4 and 3.4 min/day increase, respectively). Policy characteristics were unrelated to moderate-to-vigorous physical activity levels and time spent sedentary.ConclusionFindings indicate that policies and size of activity space had limited influence on moderate-to-vigorous physical activity and sedentary behavior, suggesting that a programmatic structure may be a more effective option to improve moderate-to-vigorous physical activity levels of children attending afterschool programs.