AN EPIDEMIOLOGIC CROSS-SECTIONAL ASSESSMENT OF MODERATE-TO-VIGOROUS PHYSICAL ACTIVITY IN 4TH, 6TH AND 8TH GRADE STUDENTS

Abstract

Contemporary American youth fail to meet national recommendations for physical activity at alarmingly high rates despite well-established protective effects of physical activity on multiple domains of health. There is an established pattern of disparity in physical activity participation whereby girls, those of lower socioeconomic status and those of African American and Hispanic backgrounds are less apt to report regular physical activity in keeping with national recommendations. Large scale investigations to increase the proportion of highly active youth have yet to realize widespread success. In light of emerging evidence suggesting physical activity levels may begin to decline earlier than previously thought, there is a possibility that research and intervention efforts to date may have approached the problem of declining activity after the risk behavior of inactivity had already been established. Despite numerous investigations into factors associated with physical activity in youth, many questions remain unanswered. Among the considerations that are not well understood is when physical activity levels begin to decline for at-risk subgroups of youth and what modifiable individual, interpersonal and/or environmental-level factors are associated with remaining highly active in these populations. This ecologically-based cross-sectional study represents an initial step toward addressing these considerations among elementary and middle school students. Self-reported primary data were collected from a convenience sample of 321 public school students from the 4th, 6th and 8th grade. Students represent the racial/ethnic and socio-economic groups at greatest risk of not meeting national recommendations for physical activity. Study questionnaires queried a range of factors believed to be associated with physical activity, such as availability of social support, self-efficacy for activity, and perceptions of environmental attributes. In addition, two separate physical activity outcome measures were assessed. Factors associated with physical activity at the univariate level (p>0.2) were included in forward stepwise binary regression models to predict reporting of high physical activity. A significant decrease in the proportion of highly active girls was noted between the 4th and 6th grade groups while the proportion of highly active boys did not differ significantly between grade levels. Among 6th and 8th grade students, the difference in physical activity between genders was significant with males reporting more physical activity than females in each grade level. Distinct variables were associated with highly active students in each grade- and gender-specific regression model. After controlling for all other included variables, high social support was most strongly associated with reporting of high activity among girls while for boys in this sample, perceived normal weight status was the strongest predictor of high activity. Among all students, use of daily active transport to school was also strongly associated with reporting of high physical activity. Future investigations involving younger students and utilizing enhanced, longitudinal designs may provide greater insight into the preliminary findings reported in this study.