Using theory and evidence to increase physical activity: let’s move it school-based multi-level intervention

Abstract

Background: No school-based physical activity (PA) interventions among youth have demonstrated long-term effectiveness, possibly due to inadequate development. This study aimed to use formative research, health behaviour theory, participatory development, and reviews of evidence to develop an intervention for vocational school youth targeting physical activity and sedentary behaviour. Methods: The research process used triangulation of several methods and sources of evidence: Systematic review identifying potentially effective Behaviour Change Techniques (BCTs) from prior interventions, needs assessment, co-design and pre-testing of intervention components, a cluster-randomised, outcome-assessor blinded feasibility study (n=43, trial registration: ISRCTN34534846), measuring acceptability as the primary and accelerometry-based PA as secondary outcomes. Findings: Review and pre-testing led to an intervention based on self-determination theory, control theory, planning and habit theories. It consists of six group sessions integrated into school curriculum targeting PA motivation and self-regulatory skills, and teacher-led sitting reduction in classrooms. Principles of group motivational interview were found to increase acceptability. Feasibility study showed high acceptability ratings of sessions and program (M=6.29 out of 7, SD=0.561) among both students and teachers. We identified suboptimal uptake of certain key BCTs (e.g. coping planning used by 32 % of intervention participants). The optimized Let’s Move It intervention added environmental and individual-level components to support key mediational processes. Discussion: Feasibility study helped to identify improvement needs, and led to the integration of habit-theory to more effectively aid teachers to incorporate sitting reduction strategies. The effectiveness of the finalized version is currently being evaluated in a randomized trial (ISRCTN10979479).