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Increased Activity in Unstructured Versus Structured Gym Time in an After-School Program
Matthew A McDougall1, Rachel Schaeffer2, Richard Holm3,4
1Department of Psychiatry, University of South Dakota Sanford School of Medicine.
Background:
More than 10 million American youth engage in after-school programs that provide an opportunity to increase physical activity. The purpose of this study was to test the hypothesis that children in unstructured gym time (free) would have greater activity than both structured gym time (structured) and when increased screen time was available.
Methods:
Three interventions were compared in a nested design, with each two-week intervention preceded and followed by a two-week control period. Seventy-four children aged 6 to 12 years were enrolled and wore pedometers during the interventions.
Results:
Mean pedometer counts were higher during free than structured gym time (p=0.01), which was more apparent in boys (p=0.02) than girls (p=0.24). Neither age nor habitual activity was associated with pedometer counts. Body mass index (BMI) was inversely correlated with counts during free gym time (r=-0.314) in boys and girls combined. Accident rates did not differ among interventions.
Conclusions:
After-school programs may be appropriate environments to increase activity levels, but greatest increases were observed in children with the lowest BMIs and may not be as effective in girls as boys. Future research should focus on identifying where children at risk of overweight spend their time and how to implement a program designed at increasing activity levels within those spaces.
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