[Activities after school time and obesity in children. Influence of family and neighborhood environment].

Background: elementary school children spend little time at the school in Mexico. The aim was to investigate the activities after school time in children and to determine the presence of overweight and obesity.

Methods: one hundred and seventy two children of both sexes were included. They belonged to the first and second grade of an official primary school from a marginalized zone. Somatometry was obtained and the type of physical practice and motifs for no practice physical activity were investigated. Descriptive statistics were applied.

Results: the frequency of underweight was 12.1 %, overweight 19 %, and obesity 18.5 %. Sedentary activities like watching television and playing video games were the most common registered, whereas sports were the lowest physical activity practiced, especially in girls. The parents' lack of time, low family income, and the scarcity of safe spaces where children can play and practice physical activity or sports were the most related factors.

Conclusions: poverty and insecurity of the neighborhoods influence the outside activities in after school time. The high frequency of underweight, overweight and obesity in school children were associated to the lack of physical activity.