Purpose: Nonalcoholic fatty liver disease (NAFLD) is the most frequent cause of chronic liver diseases in both adults and children with obesity. The aim of this study was to compare the changes in liver enzymes and metabolic profile in adolescents with fatty liver following selected school-based exercise (SBE) and high-intensity interval training (HIIT) interventions. Methods: In a semi-experimental study, 34 obese male adolescents with clinically defined NAFLD were divided into the HIIT (n=11, age=12.81±1.02 years, body mass index [BMI]=26.68 ±2.32 kg/㎡ ), selected SBE (n=11, age=13.39±0.95 years, BMI=26.47±1.74 kg/㎡), and control (n=12, age=13.14±1.49 years, BMI=26.45±2.21 kg/㎡ ) groups. The ultrasonography NAFLD grade, peak oxygen uptake (VO 2peak ), lipid profile, insulin resistance, and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of the participants were measured before and after the exercise interventions. Results: The BMI, waist-to-hip ratio, and body fat percentage of the participants decreased, and a significant increase in VO 2peak was observed after the intervention; however, the HIIT group showed a significant improvement compared with the SBE group (p<0.01). Significant reductions were observed in the levels of insulin resistance, triglyceride, total cholesterol, ALT, and AST in both groups, although high-density lipoprotein levels decreased only in the HIIT group (p<0.01). Further, a significant reduction in low-density lipoprotein level was observed in the training groups (p<0.01), but this decrease was not significant compared with the control group (p>0.01). Conclusion HIIT and SBE are equally effective in improving health parameters in obese children and adolescents.

Purpose: Nonalcoholic fatty liver disease (NAFLD) is the most frequent cause of chronic liver diseases in both adults and children with obesity. The aim of this study was to compare the changes in liver enzymes and metabolic profile in adolescents with fatty liver following selected school-based exercise (SBE) and high-intensity interval training (HIIT) interventions. Methods: In a semi-experimental study, 34 obese male adolescents with clinically defined NAFLD were divided into the HIIT (n=11, age=12.81±1.02 years, body mass index [BMI]=26.68 ±2.32 kg/㎡ ), selected SBE (n=11, age=13.39±0.95 years, BMI=26.47±1.74 kg/㎡), and control (n=12, age=13.14±1.49 years, BMI=26.45±2.21 kg/㎡ ) groups. The ultrasonography NAFLD grade, peak oxygen uptake (VO 2peak ), lipid profile, insulin resistance, and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of the participants were measured before and after the exercise interventions. Results: The BMI, waist-to-hip ratio, and body fat percentage of the participants decreased, and a significant increase in VO 2peak was observed after the intervention; however, the HIIT group showed a significant improvement compared with the SBE group (p<0.01). Significant reductions were observed in the levels of insulin resistance, triglyceride, total cholesterol, ALT, and AST in both groups, although high-density lipoprotein levels decreased only in the HIIT group (p<0.01). Further, a significant reduction in low-density lipoprotein level was observed in the training groups (p<0.01), but this decrease was not significant compared with the control group (p>0.01). Conclusion HIIT and SBE are equally effective in improving health parameters in obese children and adolescents.