Introduction
School-based physical activity (PA) interventions have largely concentrated on efficacy through outcome data, failing to account for the identification of influential factors. The optimum implementation strategy for such interventions remains equivocal, with user groups’ perceptions rarely incorporated for refinement. Therefore, this study aimed to explore children’s and teachers’ perceived effectiveness of the Dynamic Dudes PA intervention, as well as influential factors for participation and maintenance.
Methods
Dynamic Dudes, a multicomponent school-based PA intervention, incorporates in-class DVDs and stationary playground structures/markings. Twelve focus groups were conducted with 59 children (28 boys) aged 10-11 years, with 13 teachers (4 males) participating in two focus groups, from two UK primary schools. Data were analysed deductively using the RE-AIM framework, then inductively to enable emergent themes to be further explored, and presented via pen profiles.
Results
Dynamic Dudes was perceived by participants to have increased pupils PA levels, specifically within the playground, and numerous health benefits, which were perceived as an influential factor for pupil participation and teacher support. However, concerns regarding the monotony of the DVD component were highlighted, resulting in perceived barriers for participation. Paradoxically, teachers served as both positive and negative role models during the intervention.

Conclusions
Dynamic Dudes has the potential for delivering innovative, interactive PA interventions to large numbers of people, though participatory approaches that actively involve children and teachers are needed to promote PA in ways that might be better tailored and therefore more sustainable. The results of this study will form an iterative intervention refinement process.