Effects of States’ Laws on Youth Physical Activity Participation and Obesity Prevalence

The alarming prevalence of obesity and lack of physical activity among adolescents led to immediate policy action to address these concerns. Accordingly, many states introduced and enacted their own legislation to encourage physical activity in schools. Few studies have explored the effectiveness of the new legislation, however, especially at the state level. To answer the fundamental question of whether policy is effective and to describe the varying effects of state obesity policies, this study analyzed the Youth Risk Behavior Surveillance System from 2007 to 2017. Using the difference-in-differences method, this study found that legislative efforts to encourage physical activity had a significant and substantial effect on enhancing physical-activity participation and reducing adolescent obesity; however, subgroup analyses revealed that the effect was concentrated on female and white adolescents only. Additionally, the subsequent sensitivity analysis revealed that since 2015, when national attention started to divert to new health concerns (opioid abuse, for example), physical activity levels pulled back to 2009 levels. Rates of obesity and overweight have been on a sharp rise again since 2015. Lawmakers should reconsider changes in the law merging physical environments with digital environments, particularly for members of Generation Alpha, who will have ever more enticements for screen time.