Opportunities and challenges in physical activity research in young people.

The purpose of this opinion piece is to discuss opportunities and challenges to physical activity [PA] research in young people. Two key limitations were identified; (i) the lack of specificity of the types of PA measured and standards in reporting this, and (ii) lack of attention given to ecological frameworks. First, it is argued that a greater specificity of measurement is needed as PA undertaken for different purposes and/or at different levels of intensity is predicted by different determinants, and its uptake mediated by different factors. As such, researchers should carefully define the types and dimensions of physical activity they want to target and choose the appropriate physical activity measure accordingly. Second, given the relatively modest success rates of intensive PA interventions based solely on an individual approach, consideration of ecological research frameworks is advocated, as such approaches that consider multiple levels of influence on individual behaviour have the potential to facilitate far greater understanding of the full range of determinants of PA. Ultimately, it is suggested that low levels of PA among young people might be better addressed through the application of solutions at the local level, and that by tailoring PA programmes to the characteristics of the local environment and population rather than viewing contextual differences as a problem, the efficacy of promising means of intervention could be increased.