Introduction: Adolescence is one of the life stages that play a key role and is also affected by the epidemiology transition as the result of the development of the era. Consuming a lot of fast food and junk food nowadays causes adolescents, both girls and boys, to be subjected to nutritional problems such as the high body fat percentage. Adolescent boys even tend to be unaware of their health. This study aims to analyse nutritional factors which have an effect on body fat percentage in adolescent boys. Methods: This study was performed involving 1046 high school students in 5 Jakarta districts. Spearman’s correlation and multiple linear regression were used for the data analysis of this study. Results: The result shows that there was a relationship between BMI-for-age, energy and macronutrient intakes, and body fat percentage. Adolescents with excessive intakes got affected by their body fat percentage, although their BMI-for-age is normal. The result of multivariate analysis suggests that BMI-for-age had the most effect on body fat percentage. Conclusion: There needs to be a regular education for adolescent boys to be aware of their body fat percentage and other factors that have an effect on it.

Introduction: Obesity and overweight in adolescents and adults are associated with chronic diseases. The objective of this study was to determine the effect of high-intensity interval training and pre-meal water intake on the lipid profile of overweight and obese students. Methods: This was a pre-post experimental study. Twenty-seven overweight and obese students (mean BMI 26.0±3.1 kg/m2 and mean age 19.7±0.7 years) were divided randomly into three groups. The first group (n=9; BMI=26.6±3.6 kg/m2) received Plain Water Intake (PWI) intervention, whereby students received three bottles of plain water (600 mL) per mealtime (total 1.8 L/ day) and consumed ad libitum 30 to 45 minutes before mealtime (breakfast, lunch, and dinner). The second group (n=9; BMI=25.9±2.4 kg/m2) received High-Intensity Interval Training (HIIT) intervention and underwent three exercise sessions per week (18 minutes/day; 70–85% of HRmax) that was introduced through a video recording. The last group (n=9; BMI= 25.7±3.4 kg/m2) received a combination of PWI+HIIT intervention. Nutritional status, nutrient intake, and lipid profile [total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)] were assessed before and after the interventions. Data were analysed using paired sample t-test and Analysis of Variance (ANOVA). Results: The PWI group showed a significant increase in HDL-C, while the HIIT group showed a significant reduction in TC (p<0.05). On the other hand, the PWI+HIIT group showed significant improvements in lipid profile (TC, TG and HDL-C) (p<0.05). Conclusion: A combination of PWI+HIIT intervention may be effective in improving lipid profile.