Physical activity epidemiology applied to children and adolescents.

Physical activity epidemiology is central to establishing the importance of physical activity to public health. However, epidemiologic research applied to children and adolescents is still in its infancy. For example, in the studies we reviewed, many instances could be found where samples were inadequately described or where response rates and completion rates suggest that the final sample may no longer be representative of the population of interest. Many studies also had incomplete statistical adjustment for confounding influences. The need for epidemiologic research was clearly demonstrated where initially beneficial findings were negated by such adjustment. Hence, physical activity epidemiologists can play a considerable role. Their research will be the basis for expanding policy and promotional efforts to educate children and adolescents on the benefits of physical activity and the skills needed to be active, thereby helping them to build a foundation for a lifetime of physical activity.