SNAP-Ed physical activity interventions in low-income schools are associated with greater cardiovascular fitness among 5th and 7th grade students in California.

Introduction: California's Department of Public Health (CDPH) distributes Supplemental Nutrition Assistance Program-Education (SNAP-Ed) funding, known as CalFresh Healthy Living (CFHL) in California, to local health departments to implement school-based physical activity/nutrition interventions. We determined the association between intervention presence/dose and student cardiorespiratory fitness and BMI.

Methods: This cross-sectional, observational study included 5th and 7th grade students with 2016-17 FitnessGram® results who attended SNAP-Ed eligible California schools. Intervention group students attended schools with CDPH-CFHL interventions during October 2015-September 2016 (n = 904 schools; 97,504 students, 49% female); comparison group students attended schools without CDPH-CFHL interventions (n = 3,506 schools; 372,298 students, 49% female). Adjusted multilevel models determined the association between school-level intervention presence/dose and students' cardiorespiratory fitness (estimated VOmax) and BMI z-score, and tested for effect modification by student grade and sex.

Results: Students attending intervention schools demonstrated greater VOmax (males: 0.18 mL/kg per min, 95% CI: 0.03, 0.34; females = 0.26 mL/kg per min, 95% CI: 0.13, 0.39) and lower BMI z-scores (males: -0.03, 95% CI: -0.05, -0.02; females = -0.02, 95% CI: -0.04, -0.01) than students in comparison schools. Students in schools with the highest intervention levels demonstrated higher VOmax (0.37 (95% CI: 0.06, 0.16) and 0.22 (95% CI: 0.02, 0.42), respectively), than comparison students, with the strongest associations seen for females and 7th graders.

Conclusion: On average, students in schools with CDPH-CFHL physical activity interventions demonstrated better cardiorespiratory fitness and slightly lower BMI z-scores than students in comparable schools without such programing. Investment in these interventions may positively impact students' cardiorespiratory health, though further causal investigation is warranted.