Physical activity in the classroom to prevent childhood obesity: a pilot study in Santiago, Chile.

This paper describes a 4-month pilot study that tested the suitability of a physical activity intervention for first graders (children aged 6 and 7 years) in a public school in Santiago, Chile. Teachers were trained to deliver the programme in the classroom during the school day. Teachers were surveyed to determine if this intervention fit within their curriculum and classroom routines and they reported in a focus group that it was suitable for them. All children actively participated in the programme and positive changes in their attitudes towards physical activity were observed by their teachers. Anthropometrics, blood pressure and hand grip strength were measured in the students. A significant reduction was observed in children with high waist circumference ≥ 90th percentile, and in mean systolic blood pressure. However, statistical power values for those comparisons were rather low. Anthropometry and hand grip strength were not modified. The latter calculations and the lack of a control group are showing the weaknesses of this pilot study and that further research with a larger sample size and an experimental design is strongly needed.