Effect of Eight Weeks High Intensity Interval Training (HIIT) and Combined Training on Serum Liver Enzymes and Insulin Resistance Index in Women with Type 2 Diabetes

Introduction: Patients with type 2 diabetes with high insulin resistance are also at high risk for non-alcoholic fatty liver. The purpose of the present study was to investigate the effect of 8 weeks of HIIT and combined training on serum levels of liver enzymes and insulin resistance index in women with type 2 diabetes. Methods: 54 women with type 2 diabetes (age 55.77 ± 5.92 years, BMI 28.98 ± 4.9 kg/m2 and HbA1c 9.41 ± 0.82%) were randomly and equally divided into HIIT, combined training and control groups, and they received interventions for 8 weeks (3 sessions per week). Blood samples were taken 24 hours before and 48 hours after the protocol and after 12 hours fasting state. Two-way ANOVA (time*group) tests for between-group comparisons and Paired-sample t tests for within-group comparisons were used. Results: Significant differences were observed in HbA1c (P = 0.009), glucose (P = 0.007), insulin (P = 0.036), insulin resistance (P = 0.008) and AST (P = 0.005) between study groups. Tukey post-hoc test revealed that there was a significant difference between HIIT and combined training groups compared to control group in HbA1c (Respectively, P = 0.001 and P = 0.010), glucose (Respectively, P = 0.001 and P = 0.001), insulin (Respectively, P = 0.001 and P = 0.001), insulin resistance (Respectively, P = 0.001 and P = 0.001) and AST (Respectively, P = 0.006 and P = 0.006). There were no significant differences between HIIT and combined training groups (P > 0.05) in any of the markers. Conclusions: Considering the significant changes in AST enzyme and insulin resistance, it seems that HIIT and combined training both have favorite effects on AST enzyme and insulin resistance. Therefore, both types of exercise are recommended for these patients.