Individual and school-level influences on moderate and vigorous physical activity in Grenada adolescents

ABSTRACT

OBJECTIVE: The effect of school level policies on the physical activity of Grenadian children had not been studied. The present study tested the hypothesis that schools with physical activity (PA)-promoting policies would positively impact student’s levels of moderate and vigorous physical activity in Grenada. DESIGN AND METHODS: Multilevel analysis of a nationally representative sample of first year students (i.e. Form 1) (n = 138) from the twenty-three secondary schools in Grenada were assessed as part of the Grenada School Nutrition Study (GSNS). At the individual level physical activity was measured using Actigraph GT3X accelerometers. In addition to socio-demographic measures, height, weight and waist circumference (WC) were collected using standard anthropometric procedures. School-level measures were self-reported by school administrators. The school PA policy index included student to teacher ratio in physical education (PE) classes, minutes of PE per week, number of PE facilities/equipment, having at least one policy to address PE participation, having ≥1 policy for access to sports teams or activities, having a school board or council to address PE policies. RESULTS: No school-level variables were significantly related to student Moderate and Vigorous Physical Activity (MVPA). Waist circumference was the only variable that significantly predicted MVPA in both boys (p=0.03) and girls (p=0.005). In girls, overweight/obesity was significantly associated with decreased MVPA (p=0.004). CONCLUSIONS: Contrary to findings in United States children, Grenada school-level policies and environments were not related to student’s physical activity levels. Further research was needed to understand the variation in physical activity levels by schools in both male and female Grenada students.