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Related Experiment Video

Updated: Apr 12, 2026

Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity
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Making policy practice in afterschool programs: a randomized controlled trial on physical activity changes.

Michael W Beets1, R Glenn Weaver1, Gabrielle Turner-McGrievy2

  • 1Department of Exercise Science.

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|May 23, 2015
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Summary
This summary is machine-generated.

A new intervention helped afterschool programs increase children's moderate to vigorous physical activity, meeting California's 30-minute daily policy goal. This strategy improved activity levels for both boys and girls within one year.

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Area of Science:

  • Public Health
  • Childhood Obesity Prevention
  • Afterschool Program Interventions

Background:

  • Afterschool programs in the U.S. are tasked with promoting physical activity.
  • California policy mandates 30 minutes of daily moderate to vigorous physical activity (MVPA) for children in afterschool programs.
  • Effective strategies for meeting this MVPA policy goal are limited.

Purpose of the Study:

  • To evaluate a multistep adaptive intervention designed to help afterschool programs achieve the 30-minute/day MVPA policy goal.

Main Methods:

  • A 1-year group randomized controlled trial involving 20 afterschool programs and over 1,700 children (aged 6-12).
  • Intervention programs utilized the "Strategies To Enhance Practice" framework, focusing on intentional physical activity programming, staff professional development, and technical assistance.
  • The primary outcome was the accelerometry-derived proportion of children meeting the 30-minute/day MVPA policy.

Main Results:

  • Children in intervention afterschool programs were 2.37 times more likely to meet the MVPA policy compared to controls.
  • The percentage of intervention girls and boys achieving the MVPA policy increased significantly.
  • Several intervention programs successfully increased the proportion of boys and girls meeting MVPA targets.

Conclusions:

  • The "Strategies To Enhance Practice" intervention effectively increased the proportion of children meeting the MVPA policy in afterschool settings.
  • The intervention demonstrated meaningful changes within one school year.
  • Further enhancements may be needed to maximize the intervention's impact on physical activity levels.