Eficacia de un programa de Entrenamiento de Intervalos de Alta Intensidad en la modificación de variables corporales en escolares preadolescentes de un colegio de la ciudad de Temuco, Chile

Introduction: High caloric intake and lack of physical activity are causing alarming increases in the amount of overweight and obese children. The objective of this study was to determinate the effectiveness of an High-Intensity Interval Training (HIIT) program in the reduction of fat percentage, improve nutritional status and physical abilities of schoolchildren.Material and methods: 153 schoolchildren between the ages of 7 and 10 from a subsidized private school in the city of Temuco (Chile), were randomly selected, distributed in an experimental group (EG) who were applied a 12 week HIIT intervention in physical education classes, twice per week and a control group. The percentage of fat by bioelectrical impedance analysis, weight, height, body mass index and functional capacity, were measured before and after the intervention, using the 6-minute walk test.Results: In EG, the parameters that showed significant improvements (p <0.05) were weight, fat percentage that decreased while the number of meters traveled in the 6-minute test increased. At comparing ages between 7-8 only the weight and the 6- minute test and for the aged between 9-10 years only the weight and meters traveled in the 6-minute test. While it is true that only in EG all variables show a downward trend, except in the size and in the meters traveled in the 6-minute test, only statistically significant differences were obtained in those mentioned previously. Conclusions: The HIIT program in schoolchildren showed improvement in the parameters related to overweight and obesity, which highlights the importance of including interventions of this type at the school resume of our country.Introducción: La alta ingesta calórica y la falta de actividad física están provocando alarmantes alzas en la cantidad de niños con sobrepeso y obesidad. El objetivo del estudio fue determinar la eficacia de un programa de Entrenamiento de Intervalos de Alta Intensidad (HIIT, por sus siglas en inglés) en la disminución del porcentaje de grasa, mejorar el estado nutricional y las capacidades físicas de los escolares.Material y métodos: Se seleccionaron 153 escolares de edades entre los 7 y 10 años de un colegio particular subvencionado de la ciudad de Temuco (Chile), distribuidos en un grupo experimental (GE), a los que se les aplicó una intervención HIIT de 12 semanas en las clases de educación física, dos veces por semana y un grupo control. Se midió previa y posteriormente a la intervención el porcentaje de grasa por análisis de impedancia bioeléctrica, peso, talla, índice de masa corporal y la capacidad funcional mediante el test de caminata de 6 minutos. Resultados: En GE los parámetros que mostraron mejorías significativas (p