Effects of a school-based physical activity intervention on cardiometabolic health five years after cessation.

BACKGROUND: While there have been several school-based physical activity (PA) interventions targeting improvement in cardiovascular disease (CVD) risk factors, few have assessed long-term effects. The aim of this paper was therefore to determine intervention effects on CVD risk factors five years after cessation.

METHODS: Two schools were assigned to intervention (n=125) or control (n=134). The intervention school offered 210 min/week more PA than the control school over two consecutive years (4th and 5th grades). Follow-up assessment was conducted five-year post intervention (10th grade) where 180-210 (73-85%) children provided valid data. Outcomes were CVD risk factors: triglyceride (TG), total-to-high-density-lipoprotein-cholesterol ratio (TC:HDL ratio), insulin resistance (HOMA), blood pressure (BP), waist circumference (WC), and cardiorespiratory fitness (VO2peak ). Variables were analyzed individually and as a composite score through linear mixed models, including random intercepts for children.

RESULTS: Analyses revealed significant sustained five-year intervention effects for HDL (ES=.22), diastolic BP (ES=.48), VO2peak (ES=.29), and composite risk score (ES=.38). These effects were similar to the immediate results following the intervention. In contrast, while TC:HDL ratio initially decreased post intervention (ES=.27), this decrease was not maintained at five-year follow-up (ES=.09), whereas WC was initially unchanged post intervention (ES=.02), but decreased at five-year follow-up (ES=.44).

CONCLUSION: The significant effects of a two-year school-based PA intervention remained for CVD risk factors five years after cessation of the intervention. As cardiometabolic health can be maintained long-term after school-based PA, this paper demonstrates the sustainability and potential of schools in the primary prevention of future CVD risk in children.