Efficacy and mechanisms of an education outside the classroom intervention on pupils' health and education: the MOVEOUT study protocol.

Background: Education can create better opportunities for health, and vice versa. Using a so-called 'add-in' approach, school-based physical activity (PA) promotion and prevention of sedentary behaviours can increase pupils' wellbeing and learning and, on the longer term, reduce the risk of non-communicable diseases. A PA 'add-in' approach involves integrating PA into teachers' curricular obligations without being an extra burden as opposed to an 'add-on' approach which requires additional operational resources and include activities that do not explicitly contribute towards curricular targets making them less long-term acceptable in a school-based context.