Comparative Effects of Moderate vs. High-Intensity Aerobic Exercise on Abdominal Fat, Liver Enzymes, and Intrahepatic Fat in ۱۰۵ Obese Adolescents Aged ۱۰-۱۹ Years: A Prospective Cohort Study (۲۰۲۲-۲۰۲۴)

Background and Aim: Childhood obesity is a global epidemic, with ۲۰-۳۰% of adolescents exhibiting hepatic steatosis and metabolic dysfunction. While aerobic exercise is recommended, the optimal type and intensity remain unclear. This study compares the long-term effects of moderate-intensity continuous training (MICT) vs. high-intensity interval training (HIIT) on abdominal adiposity, liver enzymes, and intrahepatic fat in obese adolescents. Methods: A prospective cohort of ۱۰۵ obese adolescents (BMI _x۰۰۰۲_۶۴۹۵th percentile, aged ۱۰-۱۹) was recruited from the Tabriz Pediatric Obesity Clinic (۲۰۲۲-۲۰۲۴). Participants self-selected into: _x۰۰۰۰__x۰۰۰۰__x۰۰۰۰_HIIT Group (n=۵۲): ۴ sessions/week of cycling/running intervals (۸۰-۹۰% max heart rate). MICT Group (n=۵۳): ۵ sessions/week of brisk walking/cycling (۶۰-۷۰% max heart rate). Outcomes included changes in visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), intrahepatic fat (IHF, MRI-PDFF), liver enzymes (ALT, AST, GGT), and gut microbiota composition (۱۶S rRNA sequencing). Data were analyzed using SPSS v۲۸ and STATA v۱۷, with significance at p < ۰.۰۵. Results: VAT Reduction: HIIT group: -۱۸.۲% vs. MICT: -۹.۵% (p = ۰.۰۰۱). IHF Reduction: HIIT: -۲۷.۴% vs. MICT: _x۰۰۰۲_۱۴.۸% (p = ۰.۰۰۳). Liver Enzymes: ALT decreased by ۳۵% in HIIT vs. ۱۸% in MICT (p = ۰.۰۱). Microbiota: HIIT increased Akkermansia (+۲.۱-fold, p = ۰.۰۰۲) and reduced Firmicutes/Bacteroidetes ratio (OR: ۰.۳, ۹۵% CI: ۰.۱-۰.۷). Conclusion: HIIT significantly outperformed MICT in reducing abdominal and hepatic fat, improving liver function, and modulating gut microbiota. Adolescents in the HIIT group achieved ۶۵% resolution of hepatic steatosis vs. ۳۲% in MICT (p = ۰.۰۰۱). These findings advocate for HIIT as a frontline intervention in pediatric obesity management.

کلیدواژه ها:

Pediatric Obesity ، Aerobic Exercise ، HIIT ، Intrahepatic Fat ، Gut Microbiota ، Liver Enzymes