Relación entre la edad y tamaño corporal con el número de pasos en un recreo escolar en adolescentes

School recess is an important period for the social, emotional, physical, and cognitive development of schoolchildren. The objective was to verify whether levels of physical activity (PA) during school recess decrease according to age and body size during adolescence. A descriptive cross-sectional correlational study was conducted on 42 school-aged adolescents (21 males and 21 females) aged 10 to 14 years from a municipal school in the province of Talca (Chile). Anthropometric variables of body weight (kg) and height (cm) were evaluated. For body size, the formula of Haycock et al. (1978) was used to estimate body surface area (BSA). PA levels were measured by the number of steps taken during school recess (20 minutes) using pedometers. The number of steps taken by men was 4268.9±1103.0 steps and by women was 2490.0±1487.3 steps. The relationship between the number of steps and chronological age in men was r= -0.33 and in women was r= -0.53. Body size values increase as PA levels (number of steps during recess) decrease, with r = -0.24 for males and r = -0.29 for females. This study showed that as adolescents age and their body size increases, the number of steps taken during school recess decreases, with this reduction being more pronounced in females than in males.