High-Intensity Interval Training Reduces Liver Enzyme Levels and Improves MASLD-Related Biomarkers in Overweight/Obese Girls
Question
Does 9 weeks of HIIT improve liver enzymes and other MASLD-related biomarkers in overweight or obese adolescent girls?
Summary
Thirty-three overweight or obese adolescent girls completed a 9-week randomized trial of school-based running HIIT or control. The HIIT group improved body composition, systolic blood pressure, maximal aerobic speed, ALT, AST, lipids, glucose, insulin resistance, and HDL-C, while the control group did not change. Training adherence was not recorded, but no injuries occurred.
Methodology
- Overweight or obese adolescent girls from secondary schools.
- 33 participants.
- Running.
- Work intervals: 30 seconds at 100-105% MAS.
- Recovery: 30 seconds active recovery at 50% MAS.
- Intensity: 100-105% MAS.
- Not fully reported; includes 15 min warm-up and 15 min cool-down.
- 3 sessions/week.
- 9 weeks.
- Nine-week randomized controlled trial
- ALT and AST, HOMA-IR, Lipids, and Maximal aerobic speed were tracked.
Outcomes
Liver enzymes
ALT and AST decreased in the HIIT group and did not change in controls.
ALT p=0.013, ES=0.47; AST p=0.012, ES=0.58.
Insulin resistance
HOMA-IR decreased in the HIIT group and did not change in controls.
HOMA-IR p=0.010, ES=0.47.
Body composition and SBP
Body mass, BMI, body fat, waist circumference, and systolic blood pressure improved in the HIIT group.
Body mass p<0.001; BMI p=0.001; BF p<0.001; WC p=0.003; SBP p=0.011.
Uric acid and platelets
Uric acid and platelet indexes did not significantly change.
Insights
- Thirty-second running intervals may be practical for adolescent school settings with supervision.
- Claims about MASLD should be framed as biomarker improvement, not confirmed liver fat reversal.
Limitations
- Small sample
- Girls only
- No liver fat imaging
- Diet not controlled
- Exercise adherence not recorded
Safety
- No injuries occurred.
- Exercise adherence was not recorded.