An ecological-based approach to examining barriers and facilitators of a physical activity intervention

Texas I-CAN! promotes physical activity (PA) among elementary school children by incorporating 10-15 minute, physically-active, academic lessons into the classroom. A socioecological approach to evaluate effectiveness could provide a deeper understanding of mechanisms promoting or hindering PA. Three studies examined the impact of implementation quality on child PA during active lessons. Teachers from 20 schools self-reported attitude and perceived behavioral control (PBC) related to implementation, and perceptions of school climate. Staff observed teacher feedback to students during active lessons and student PA. Student PA was also measured objectively (i.e. accelerometry). Before examining how teacher-level factors interact to impact student PA, foundational work was necessary. First, several mathematical cut-points have been developed to classify PA intensity among children. Though research indicates that cut-point selection impacts classification of PA among children aged 6-10 years, this has not demonstrated with school-specific PA. Study 1 demonstrated that cut-point selection impacts estimates of in-school PA intensity and students meeting PA guidelines. Second, quality of process (i.e. teachers’ ability to engage students in intervention programs) has been linked to program implementation. Study 2 examined associations between teacher feedback during lessons and staff-rated, class PA intensity. Positive associations between PA-related feedback (i.e. reinforcement, technical instruction) and PA intensity were found. Technical instruction was positively associated with how often and how many students were active during lessons. Negative feedback was inversely related to these outcomes. Study 3, then, examined the interrelatedness of quality of process (i.e.PA-related feedback), teacher-level data (i.e. attitudes, PBC, perceptions of school climate), and implementation dose, and their impact on objectively-measured student PA using structural equation modeling. PA-related feedback and dose were positively associated with PA intensity. PBC and attitude towards implementation were positively related to dose. Perception of higher quality school climate was associated with greater PBC and poorer attitudes. PBC was positively, and attitudes negatively, associated with PA-related feedback. Results may inform optimization of future physically-active academic lesson interventions. Identification of factors that impact implementation of active lessons provides opportunities to tailor teacher trainings to focus on these important factors and to intervene if implementation begins to wane during intervention periods.