Lessons learned from school-based skeletal loading intervention trials: putting research into practice.

In recent years, there have been a number of school-based physical activity intervention trials aimed at optimizing bone development. Various approaches have been taken including interventions ranging from 3 to 50 min in length performed 2-5 times per week incorporated within the school day (typically in physical education) or as an after-school program. Overall, these studies showed that school-based skeletal loading interventions are efficacious, safe, and feasible. Furthermore, studies to date have shown that interventions are most effective when initiated during prepuberty and early puberty, and consist of dynamic activities that are high in magnitude (i.e. jumping, skipping, hopping) and include multidirectional movements. Recent work also suggests that adding rest intervals and performing short bouts of activity a few times per day may enhance the effectiveness of loading on bone health. In this chapter, we discuss important training principles and lessons learned from these intervention trials and provide practical guidelines, tips and sample programs that can be used by health care professionals interested in optimizing bone health of children and adolescents.