Background: Evidence of the positive effects of school physical activity (PA) interventions, including classroom-based PA (CBPA), is rapidly growing. However, few studies examine how variations in scheduled PA opportunities and teacher-implemented CBPA affect students’ PA outcomes. Methods: Teachers at 5 elementary schools attended training on how to implement CBPA. Data on school-day PA opportunities [physical education (PE), recess, and CBPA] were obtained via calendar and teacher-recorded CBPA logs. Daily step counts were measured via accelerometry in 1346 students across 65 classrooms in first through fifth grades. Results: PE, recess, and CBPA contributed significantly to students’ daily steps. Males accrued more steps than females over the school day, during PE, and during recess. No gender disparity was seen in the amount of additional steps accrued during CBPA. Overall step counts were lower among fifth-grade students versus first-grade students, but CBPA attenuated this difference such that grade...

The intentional integration of physical activity in elementary school classrooms—including brief instructional breaks for activity, or integration into lessons—can benefit children’s physical activity and education outcomes. Teachers are key implementation agents, but despite physical activity in the classroom being an evidence-informed practice, many teachers do not regularly implement it. The aim of this study was to obtain updated nationally representative prevalence estimates in United States public elementary schools, regarding four key outcomes: (1) school adoption of physically active lessons (PA lessons); (2) school adoption of physical-activity breaks (PA breaks); (3) penetration in the classroom, defined as ≥50% of teachers using PA breaks; and (4) dose, defined as an average of at least 50 min per week of PA breaks. We examined variations in outcomes by school demographic characteristics, and by three factors hypothesized to be implementation facilitators (administrative support, financial resources, and presence of a wellness champion at the school). In the 2019–20 school year, surveys were distributed to a nationally representative sample of 1010 public elementary schools in the US; responses were obtained from 559 (55.3%). The weighted prevalence of schools reporting adoption of PA lessons was 77.9% (95% CI = 73.9% to 81.9%), and adoption of PA breaks was nearly universal at 91.2% (95% CI = 88.4% to 94.1%). Few demographic differences emerged, although adoption of PA lessons was less prevalent at higher-poverty schools (73.9%) and medium-poverty schools (77.0%) as compared to schools with lower poverty levels (87.1%; p < 0.01). Across all four outcomes, associations emerged with facilitators in multivariable logistic regression models. The prevalence of adoption of PA lessons, adoption of PA breaks, and dose of PA breaks were all significantly higher at schools where administrative encouragement occurred more frequently. Financial support was associated with implementation outcomes, including adoption of PA lessons, and penetration and dose of PA breaks. Presence of a champion was associated with higher prevalence of reporting adoption of PA lessons. School leaders can play a crucial role in supporting teachers’ implementation of PA breaks and lessons in the classroom, through providing financial resources, encouragement, and supporting champions. Effective school-leadership practices have the potential to positively impact students at a large-scale population level by supporting implementation of PA lessons and breaks.

Classroom-based physical activity (CBPA) is increasingly recommended as a method to support children’s physical activity, health, and academic performance. Many adoption-ready programs exist to aid in the implementation of CBPA in schools; yet, implementation rates remain low. The purpose of this study was to evaluate the extent to which resources provided by adoption-ready CBPA programs addressed theory-based implementation contextual factors to support implementation. Existing CBPA programs (N = 37) were identified through Internet searches and all materials (e.g., implementation guides) provided by each program were coded for their inclusion of 51 implementation factors based on the Consolidated Framework for Implementation Research (CFIR). Analyses were conducted to compare inclusion of implementation factors across CFIR Domains and by three program groupings: free (yes/no), research evidence (yes/no), and targeted to teacher only (vs. school). Programs covered a mean of 25.9 per cent (SD = 18.7 per cent) of the 14 Inner Setting implementation factors, 34.2 per cent (SD = 18.0 per cent) of the 6 Characteristics of Individuals implementation factors, and 34.8 per cent (SD = 24.3 per cent) of the 8 Process implementation factors. Programs with research evidence covered more implementation factors than programs without research evidence (43.7 vs. 25.9 per cent; p < .05). Although numerous adoption-ready CBPA programs are available and have many strengths, their inclusion of theory-based factors that support or inhibit implementation is generally low. Consideration of such factors, including organizational climate and teacher-level behavior change, is likely critical to supporting ongoing school-wide implementation of CBPA. Research is needed to develop and test effective strategies for addressing these factors to support more widespread CBPA implementation.