EXERCISE INTENSITY'S EFFECT ON METABOLIC HEALTH IN PATIENTS WITH NAFLD AND COEXISTING TYPE 2 DIABETES MELLITUS: A COMPARATIVE STUDY

Abstract

Introduction:  Non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are two chronic diseases that are becoming more and more common. They frequently combine, which exacerbates their progression and increases cardiovascular disease and death risk. It is still unknown what level of intensity will produce the best health results, even though physical activity is essential for managing many disorders. Although moderate-intensity continuous training (MICT) is typically advised, high-intensity interval training (HIIT) may enhance metabolic and cardiovascular health. This study aims to evaluate the effects of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) on metabolic health outcomes in individuals with NAFLD andT2DM.

Methods: In this prospective comparison study, 92 patients with T2DM and NAFLD diagnoses participated. Five times a week, the MICT group (Control group) engaged in continuous aerobic exercise for 30 to 45 minutes at 50–60% of their maximum heart rate (HRmax). For 30 to 45 minutes each session, the HIIT group (study group) alternated high-intensity intervals at 85–95% HRmax with rest intervals three times a week. The primary outcomes included changes in insulin sensitivity (assessed through HOMA-IR and OGTT) and liver fat content (assessed by MRI). HbA1c levels, liver enzyme levels (ALT, AST), body composition (assessed through DEXA), cardiovascular risk factors (blood pressure, lipid profile), and overall well-being (SF-36) were among the additional objectives.

Results: The study was completed by 92 study subjects (MICT: n = 45; HIIT: n = 47). Both groups showed notable enhancements in HOMA-IR, OGTT, and liver fat content, while the HIIT group showed more significant reductions in HOMA-IR (1.8 ± 0.7 vs. 1.2 ± 0.6, p=0.054) and liver fat content (8.5 ± 3.2% vs. 5.3 ± 2.9%, p=0.031). The reductions in systolic blood pressure (8.5 ± 2.3 mmHg vs. 5.3 ± 1.5 mmHg, p=0.002), diastolic blood pressure (5.2 ± 1.6 mmHg vs. 3.4 ± 1.2 mmHg, p=0.011), LDL cholesterol (17 ± 6 mg/dL vs. 10 ± 4 mg/dL, p=0.007), and triglycerides (27 ± 8 mg/dL vs. 15 ± 5 mg/dL, p=0.001) were more markedly reduced by high-intensity interval training (HIIT).

Conclusion: In patients with T2DM and NAFLD, MICT and HIIT successfully enhanced cardiovascular and metabolic health. HIIT was more successful in lowering hepatic fat content, improving insulin sensitivity, reducing cardiovascular risk factors, and improving overall well-being. According to these findings, HIIT might be a more effective form of exercise for managing T2DM and NAFLD.