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Have States Reduced Obesity by Legislating More Physical Activity in Elementary School?
Paul T von Hippel1, David E Frisvold2
1Center for Health and Social Policy, Lyndon B. Johnson School of Public Affairs, University of Texas, Austin, USA.
Abstract:
Policy Points Between 1998 and 2016, 24 states and the District of Columbia passed laws meant to increase the time that children spent in physical education (PE) or other school-based physical activity (PA). Schools largely disregarded changes to PE/PA laws, which did not increase the time that children spent in PE or recess and did not reduce body mass index, overweight, or obesity. Closer oversight of schools would be needed to improve compliance with state PE and PA laws. Yet, even with better compliance, we estimate that PE and PA policies would be inadequate to reverse the obesity epidemic. Policies should also address consumption, both inside and outside of school.
Context:
To control childhood obesity, leading medical organizations have recommended increasing the time that children spend in physical education (PE) and other school-based physical activity (PA). Yet, it is unknown how many states have passed laws that codify these recommendations, and it is unknown what effect changing state laws has had on obesity or the time that children actually spent in PE and PA.
Methods:
We joined state laws to national samples of 13,920 children from two different cohorts of elementary students. One cohort attended kindergarten in 1998; the other attended kindergarten in 2010; both cohorts were followed from kindergarten through fifth grade. We estimated the effects of changes to state laws in a regression with state and year fixed effects.
Findings:
Twenty-four states and the District of Columbia increased the time that children were recommended or required to spend in PE or PA. These changes in state policies did not increase actual time spent in PE or recess, did not affect average body mass index (BMI) or BMI Z score, and did not affect the prevalence of overweight or obesity.
Conclusion:
Increasing the PE or PA time required or recommended by state laws has not slowed the obesity epidemic. Many schools have failed to comply with state laws. A back-of-the-envelope calculation suggests that, even with better compliance, the legislated changes in PE laws might not have changed energy balance enough to reduce obesity prevalence.
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