Playing more sports cuts obesity in teens

Playing on more than 1 sports team during the school year could reduce obesity rates among high school students by more than 25%, a new study reports. Obesity prevalence would also decrease substantially if teenagers walked or biked to school 4 or 5 days a week.

Telephone surveys of 1,718 high school students-most in ninth or tenth grade and about half girls-and their parents that were conducted during a 7-year longitudinal adolescent health study found that 29% of the group were overweight/obese (body mass index [BMI] for age ≥85th percentile) and 13% were obese (BMI for age ≥95 percentile). Researchers asked about team sports participation, other extracurricular physical activity, commuting to school, physical education, recreational activity, screen time, diet quality, and demographics.

After adjusting for variables including weight at the beginning of the study, diet, sex, race, grade, screen time, academic performance, and employment status, researchers found an inverse relationship between participation on sports teams and both overweight/obesity and obesity.

Risk estimates indicated that the prevalence of obesity and overweight/obesity would decrease by 26.1% and 10.6%, respectively, if all adolescents played on at least 2 sports teams per school year. Playing a single sport did not strongly affect weight.

Commuting to school by walking or bicycling was inversely related to obesity but not overweight/obesity. The prevalence of obesity would likely decline by 22% if all teens walked or biked to school at least 4 days a week. The effect of active commuting on weight requires further study, say investigators.

Because participation in team sports was the only physical activity inversely related to both overweight/obesity and obesity, the researchers recommend expanding opportunities for adolescents at all levels of athletic ability to play sports as a priority in preventing obesity. They speculate that the consistent moderate to strenuous activity required by regular practices and competitions may account for the relationship between sports and weight.

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