The influence of physical activity, socioeconomic status, and ethnicity onthe weight status of adolescents

Objective: This study examined the effects of physical activity, television viewing, video game play, socioeconomic status (SES), and ethnicity on bod y mass index (BMI). Research Methods and Procedures: The sample was 2389 adolescents, 10 to 16 years of age (12.7 +/- 1.0 years); 1240 (52%) females and 1149 (48%) males; 77% white and 23% African American; from rural (77%) and urban (23%) setti ngs. BMI and skinfolds were directly assessed. All other data were obtained from questionnaires. Results: Watching television on non-school days was related to being overwe ight (p < 0.005). However, when BMI analyses were adjusted for ethnicity an d SES, there were no significant effects of television viewing on BMI (p > 0.061). Increased hours of video game play enhanced the risk of being overw eight for both genders when analyses were adjusted for ethnicity and SES (p < 0.019). In males, participation in as little as one high-intensity physi cal activity 3 to 5 days a week decreased the ethnic- and SES-adjusted rela tive risk of being overweight (RR = 0.646; CI: 0.427 to 0.977). For females , the ethnic- and SES-adjusted relative risk for being overweight was not s ignificantly altered by physical activity. The logistic analyses further in dicated the influence of low SES and African American ethnicity overshadowe d any direct effect of television or videos. Discussion: Because weight status of male adolescents appears to be more re lated to exercise habits than to television or video game habits, increased participation in high-intensity exercise appears to be important. For fema les, neither videos nor exercise habits appear to be related to risk of bei ng overweight. However, ethnicity and SES may be important factors that can influence body weight status, while television viewing may be of some impo rtance. Thus, programs to reduce obesity in female adolescent should focus their efforts in lower SES communities.