| The purpose of this dissertation was to investigate determinants of, and approaches to promote, physical activity and aerobic fitness among Wisconsin middle school children. The approach used the socio-ecological model, which posits that health behaviors are influenced by factors atvarious levels. These levels range from the individual to the societal realm, and interventions utilizing multiple levels can be effective towards promoting healthy practices.;The first paper showed that aerobic fitness holds a marginally significant association with future physical activity. The second paper demonstrated that, on the population level, disparities exist in aerobic fitness between race/ethnicity groups among 6th grade students. Much more limited disparities exist for activity levels. The third paper showed that it is feasible to implement school-based strategies to promote physical activity and aerobic fitness among middle school children. However, in our results, the implementation did not translate into significant positive changes in activity or fitness between years.;Overall, these findings have implications for future research and current practice. First, improving students' fitness levels may result in increased activity levels both in and out of school. Second, a link exists between poor aerobic fitness and insulin resistance, a marker for the development of type 2 Diabetes Mellitus. The disparities in fitness levels suggest that emphasizing increased aerobic fitness in schoolsmay prevent chronic disease disparities in future adult generations. Finally, addressing fitness and activity at the school-level can provide widespread population health benefits given the high level of reach, adoption, and implementation observed in our study. |
