The physical activity level of Mexican children decreases upon entry to elementary school.

Objective. To compare the physical activity patterns of a cohort of Mexican children in kindergarten (K), first (1ES) and second grade (2ES) of elementary school. Material and Methods. The physical activity of 217 children (123 girls and 94 boys) aged 5-6 years was measured (five full-day triaxial accelerometry) annually. Weekday and weekend moderate/ vigorous physical activity (MVPA) and school and off-school MVPA was calculated. Comparisons between surveys were made using longitudinal multilevel generalized linear models. Results. Weekday MVPA was 22 and 37 min/d flower for 1ES (p=0.06) and 2ES (p<0.01), respectively, compared to K. School MVPA for 1ES and 2ES was 37 (-5.0 min/h) and 40% (-5.5 min/h) (p<0.001) lower , respectively, compared to K. No differences were found between weekend and off-school MVPA among school stages (p>0.5). Conclusion. MVPA was significantly reduced from K to ES, in part because of a decline in MVPA during school activities. Interventions targeted to school environment modifications should be promoted. [ABSTRACT FROM AUTHOR]