Respuesta en escolares con obesidad al ejercicio intervalado de alta intensidad aplicado en el contexto escolar

Background: High-intensity interval training (HIIT) has been widely used to fight cardiovascular risk factors in adolescents and adults, but no data are available on its applicability in children. Objectives: To assess the effects of HIIT on different anthropometric and cardiovascular parameters of overweight and obese children aged 7-9 years. Material and methods: Four groups were formed: 1) an overweight control group (OWCG, n = 30, BMI = 21.60 ± 3.72 kg/m²); 2) an obesity control group (OCG, n = 34, BMI = 23.92 ± 3.11 kg/m²); 3) an overweight intervention group (OWIG, n = 69, BMI = 20.01 ± 1.88 kg/m²), and 4) an obesity intervention group (OIG, n = 141, BMI = 24.12 ± 2.66 kg/m²). BMI, body fat (BF), waist circumference, height-waist ratio, systolic and diastolic blood pressure and cardiorespiratory fitness (CRF) were assessed before and after intervention. Results: There were significant differences in BMI (P <.001), BF (P <.001), and CRF (P <.001) between the groups (control vs. intervention) before and after intervention (OWCG vs. OWIG and OCG vs. OIG). BMI decreased in the OWIG (BMI, 20.01 ± 1.88 at baseline vs. 19.00 ± 2.02 after HIIT, P <.001) and OIG (BMI, 24.12 ± 2.66 at baseline vs. 23.23 ± 3.23 after HIIT, P <.001) groups. Similarly, BF decreased in the OWIG (BF, 21.84 ± 4.97 at baseline vs. 19.55 ± 4.81% after HIIT, P <.001) and OIG (BF, 30.26 ± 11.49 at baseline vs. 26.81 ± 6.80% after HIIT, P <.001) groups. CRF improved in both intervention groups (P <.001). There was a significant decrease in the prevalence rate of schoolchildren with obesity (from 66.4% to 49.6%) (P <.001). Conclusion: The intervention conducted in the school setting improved the anthropometric and cardiovascular parameters of schoolchildren, and also allowed for reducing the proportion of schoolchildren with obesity.