Research Finds School Phys-Ed Classes Do Little to Promote Exercise, Fight Obesity
In 2005 alone, 44 states introduced bills to increase or reform school PE. Increased PE requirements, however, have no impact on the overall levels of physical activity among boys, report John Cawley of Cornell University, economist Chad Meyerhoefer of the Agency for Healthcare Research and Quality, and David Newhouse of the International Monetary Fund. And, among girls, the researchers found that although increased PE can lead to more time spent exercising vigorously, it actually decreases the number of days in which girls engage in light physical activity.
“Apparently, when girls exercise in class, they become more sedentary during the discretionary hours of their week”
"Apparently, when girls exercise in class, they become more sedentary during the discretionary hours of their week," the study's authors explain. "This propensity occurs predominantly among girls who are less active in the first place."
The study's findings suggest that the effect of increased state PE requirements is minimal at best. The researchers report that increased PE requirements had no effect on weight for either gender. And, although increased active PE time does raise the number of days that girls report at least 20 minutes of vigorous exercise, the positive effect on girls' behavior is tempered by a decrease in the number of days girls engage in 30 minutes or more of light physical activity. Notably, the researchers found that this offsetting behavior is most prominent among girls who are not otherwise active in team sports.
To measure the impact of PE, Cawley, Meyerhoefer, and Newhouse compared the self-reported PE activity times, overall physical activity levels, and body mass index (BMI) of students who are subject to different state PE requirements. They gathered information on state PE requirements from "The Shape of the Nation Report," a 2001 survey conducted by the National Association for Sport and Physical Education, and data on the activity and weight of almost 37,000 high school students from the Youth Risk Behavior Surveillance System, a nationally representative survey that was established by the CDC to monitor the prevalence of risky youth behaviors.
In general, estimated active time in PE class is low, with an average reported level of 16 minutes per day and only 2 minutes per day for the median student. Median active time is much lower than the average time because a smaller number of programs actively promote exercise; many more do little to facilitate much actual exercise. Many schools offer PE class fewer than five days per week, and many districts only require PE for one or two years of high school.
The Centers for Disease Control and Prevention has reported that since 1970 the fraction of adolescents who are overweight has more than tripled, from under 5 percent to more than 15 percent.
Read "Not Your Father's PE: Obesity, Exercise, and the Role of Schools" now available in early release online at www.EducationNext.org.
John Cawley is an associate professor in the Department of Policy Analysis and Management at Cornell University and a faculty research fellow of the National Bureau of Economic Research. Chad Meyerhoefer is an economist at the Agency for Healthcare Research and Quality. David Newhouse is a technical assistance adviser at the International Monetary Fund.
Education Next is a scholarly journal published by the Hoover Institution that is committed to looking at hard facts about school reform. Other sponsoring institutions are the Harvard Program on Education Policy and Governance and the Thomas B. Fordham Foundation.