Background: Despite the importance of social support in promoting physical activity, little is known about the relative influence of the type or source of social support on adolescent girls' physical activity and sedentary behaviors. This study examined the associations of two types of social support (social participation in and social encouragement for physical activity) and two social support sources (family and friends) with self-reported daily minutes of physical activity and sedentary behavior among sixth-grade girls in Texas.Methods: A secondary analysis of 718 sixth-grade girls between the ages of 10 to 14 was performed using cross-sectional baseline data from an osteoporosis prevention intervention study. Physical activity and sedentary behaviors (television-video viewing and computer-video game playing) were assessed using 3 administrations of the Self-Administered Physical Activity Checklist; social support indicators were assessed with Likert-type items from a psychosocial questionnaire.Results: In multiple linear regression analyses, friend physical activity participation (partial correlation coefficient (r) = 0.10, p = .009) and friend (r = 0.12) and family encouragement (r = 0.11) (p < .01, respectively) were positively related to moderate-to-vigorous physical activity in the full model with other support variables, BMI and ethnicity; friend encouragement was the only variable positively related to vigorous physical activity (r = 0.11, p = .005). Family participation in physical activity had the strongest negative correlation with total minutes of television-video viewing and computer-video playing (r = -0.08, p < .05).Conclusion: Findings lend support to the importance of social support for physical activity among adolescent girls but suggest that the source and type of social support may differ for physical activity and sedentary behaviors. Further research is needed to assess the causal or reciprocal relation between the roles of friends and family in promoting physical activity and of family physical activity in decreasing sedentary behaviors among early adolescent girls.

Weight perceptions and weight control behaviors have been documented with underweight and overweight adolescents, yet limited information is available on normal weight adolescents. This study investigates the prevalence of overweight misperceptions and weight control behaviors among normal weight adolescents in the U.S. by sociodemographic and geographic characteristics. We examined data from the 2003 Youth Risk Behavior Survey (YRBS). A total of 9,714 normal weight U.S. high school students were included in this study. Outcome measures included self-reported height and weight measurements, overweight misperceptions, and weight control behaviors. Weighted prevalence estimates and odds ratios were computed. There were 16.2% of normal weight students who perceived themselves as overweight. Females (25.3%) were more likely to perceive themselves as overweight than males (6.7%) (p < 0.05). Misperceptions of overweight were highest among white (18.3%) and Hispanic students (15.2%) and lowest among black students (5.8%). Females (16.8%) outnumbered males (6.8%) in practicing at least one unhealthy weight control behavior (use of diet pills, laxatives, and fasting) in the past 30 days. The percentage of students who practiced at least one weight control behavior was similar by ethnicity. There were no significant differences in overweight misperception and weight control behaviors by grade level, geographic region, or metropolitan status. A significant portion of normal weight adolescents misperceive themselves as overweight and are engaging in unhealthy weight control behaviors. These data suggest that obesity prevention programs should address weight misperceptions and the harmful effects of unhealthy weight control methods even among normal weight adolescents.

In 2001, the 77th Texas legislature passed Senate Bill 19 requiring students in publicly funded elementary schools to participate in physical activity and schools to implement a coordinated school health program by September 1, 2007. We report on awareness of and adherence to Senate Bill 19 in a statewide sample of elementary schools and a subsample in two public health regions located along the Texas–Mexico border. Statewide, structured interviews with principals indicated high awareness of Senate Bill 19's requirements, but lower awareness of the need for parental involvement. Only 43% of Texas schools had adopted their coordinated program 1 year or less before the implementation deadline. Principals reported an average of 179 min of physical education per week, higher than the 135-min mandate. Among the subsample border schools, principals' physical activity reports were consistent with teacher records and student reports. Further, direct observation of physical education indicated that 50% of class time was spent in moderate and vigorous physical activity, meeting the level of physical activity intensity recommended by Healthy People 2010. The differences observed by public health regions included: more physical activity minutes in Region 10 (231 min compared to 217 min in Region 11); higher adoption of coordinated school health programs (92% compared to 75%); more district-level school health advisory committees (58% compared to 38%) and school-level school health advisory committees (83% compared to 25%); and a lower prevalence of obesity in 4th grade students (21% compared to 32%). Differences by region suggest that Senate Bill 19 is not being adhered to equally across the state, and some regions may require further support to increase implementation. Results underscore the importance of continued monitoring of enacted legislation, and that legislation for child health that focuses on school programs and policies requires funding and refinement to produce the intended effect.