Aerobic Power in Prepubescent Children with Different Levels of Physical Activity (Potencia Aeróbica en Niños Prepubescentes con Diferentes Niveles de Actividad Física)

The purpose of the study was to compare the aerobic power of prepubescent children (Tanner 1 stage). Participants were 95 children between 7 and 9 years old, divided into 4 physical activity level groups: a) Trained (n = 24), b) Sport beginners (n = 23), c) Active (n = 24), and d) Sedentary (n = 24). Physical activity level was determined by a three-day physical activity diary. Subjects performed a treadmill Balk protocol to obtain their peak oxygen uptake. Comparisons were made using ANOVA two-way and post hoc Tukey followed-up the significant differences for p< 0,05. Trained, sport beginners and active children presented similar amount of physical activity level, but they significantly differ from the sedentary children (p< 0.05). Overall boys (50.67 ± 8.52 ml/kg/min) had higher relative peak oxygen uptake than girls (45.19 ± 6.44 ml/kg/min). The gender by group interaction showed that this difference is explained by the superior values of the trained boys (58.80 ± 8.98 ml/kg/min) when compared to trained girls (47.51 ± 5.68 ml/kg/min), even though they presented the same amount of physical activity level. The trained group (53.16 ± 9.34 ml/kg/min) showed higher relative peak oxygen uptake compared to sport beginners (48.90 ± 6.54 ml/kg/min), active children (45.46 ± 7.50 ml/kg/min) and sedentary children (44.63 ± 9.52 ml/kg/min). The results suggest that prepubescent children that participate in systematized trained programs have better physiological indicators for aerobic fitness.Key words. aerobic power, physical activity, children.Resumen. El propósito del estudio fue comparar la potencia aeróbica de niños prepubescentes (Estadio de Tanner 1). Participaron 95 niños y niñas con edades entre 7 y 9 años, divididos en 4 grupos basados en sus niveles de actividad física: a) Entrenados (n = 24), b) Principiantes en deportes (n = 23), c) Activos (n = 24), y d) Sedentarios (n = 24). Los niveles de actividad física se determinaron por medio de un diario de actividad física de tres días. Los participantes realizaron el protocolo de Balke en banda sin fin para obtener el consumo de oxígeno pico. Se hicieron comparaciones con ANOVA de dos vías y post hoc de Tukey cuando se encontraron diferencias significativas a un p < 0.05. Los niños prepubescentes entrenados, principiantes en deportes y activos presentaron niveles de actividad física similares, pero fueron significativamente diferentes de los niños sedentarios (p < 0.05). En general, los niños presentaron may