The Effects of Eight-Week Resistance Training on Fatty Liver and Lipid Profile Indices, Insulin Resistance and Body Composition in Diabetic Women with Non-Alcoholic Fatty Liver disease

Increased prevalence of obesity is known as the main reason for the spread of metabolic diseases including nonalcoholic fatty liver disease (NAFLD). On the other hand, research on the effect of resistance training on diabetic people simultaneously with NAFLD is limited. Therefore, the present study was conducted with the aim of determining the effects of 8 weeks of resistance training on body composition indices, fat profiles and fatty liver in diabetic women with non-alcoholic fatty liver.

This experimental study was performed with two groups including training group (15) and control (15). 30 diabetic women in the age range of 45 to 65 years were randomly selected (48 ± 8 years old age, 158 ± 2, weight of 76 ± 8 kg) and were divided into two groups of control and training. The criteria for entering the research included at least 6 years of history of diabetes, BMI between 25 and 36 (kg / m2), a glycemic index between 120 and 150 (mg / dl), glycosylated hemoglobin (HA1C) between 6.5 to 9 and having a fatty liver of grid 2 and 3 (via sonography). Exclusion criteria included known genetic disease, endocrine disease and advanced complications of diabetes, hepatitis C and B and autoimmunity, hemochromatosis, or liver-related diseases, cardiac-pulmonary disease and drug and alcohol consumption. Weight and BMI were measured by using  body  composition device model (Inbody570). Body fat percentage (BFP) was measured by a three-point method (arms, thighs and supraspinatus) using a Harpanden metal caliper (with an accuracy of 0.05 mm) and calculated by Jackson and Pollack formulas. Serum levels of fasting blood sugar, LDL, HDL, AST and ALT were analyzed using a bionic diagnostic kit (made in Iran) with a mindray analyzer BS-480 and insulin using a monobind kit (made in the USA). On the other hand, the training group performed resistance exercises for upper and lower torso muscles in three sets (70-50% of one maximum repetition, 10-16 repetitions) in each session and three sessions per week for eight weeks. Participants performed eight different strength training, including large muscle groups, on the machines. These movements include: Bench press, Barbell curl, Lying triceps press, lat pull down, leg press, leg extension, Lying leg curl and Standing calf raise. Each training session includes warm-up phase using stretching movements for 5 minutes, resistance movement phase in the form of three sets (50-70% of one maximum repetition, 10-16 repetitions) for 35 to 50 minutes and Finally, the cooling-down step was for 5 minutes. A maximum repetition test was used to measure the maximum strength of the leg and chest muscles. A 90-second break was also allowed between sets. The training duration gradually increased from 45 in the first week to 60 minutes in the eighth week. During these two months, individuals were asked to refrain from engaging in physical activity outside of the program. The subjects in the control group were also asked not to do any sports activities during the program and to do only their normal daily activities. Two-way ANOVA with repeated measures was used to determine the differences and independent t-test was used to compare the changes of the two groups in pre-test and post-test (∆) and interval confidence of 95% was considered at all stages of the test.

The results of two-way ANOVA with repeated measurements showed that there was a significant difference between the groups in the interaction (group × time) in weight, WHR, body fat percentage and a maximum repetition (leg press and chest press) (P <0.05) but this result in BMI changes was not significant (p>0.05). In addition, the results of two-way ANOVA with repeated measures showed that there was a significant difference between the groups in the interaction (group × time) and in the variables of glucose and insulin (P <0.05). Also, comparing the interaction (group × time) using two-way ANOVA test with repeated measures showed that there were a significant difference between the control and training groups in HDL, LDL, TG, TC variables (P <0.05). Also, the results of the two-way ANOVA test with repeated measures showed that in the within group comparison (difference between pre-test and post-test) and in ALT and AST variables, a significant difference were observed in both control and exercise groups (P <0.05). Also, comparing delta changes (pre-test and post-test changes) using independent t-test, the results showed that there were a significant difference between ALT and AST variables between control and training groups (P <0.05).

According to the results of this study, it can be said that performing eight weeks of moderate-intensity resistance training can improve metabolic parameters such as glycemic index, insulin resistance, 1RM and body composition index (weight, BMI, WHR) and body fat percentage) in women with T2DM and NAFLD. These results suggest that resistance training can modulate the levels of lipid profile variables and liver enzymes closer to normal by compensating for the destructive effects of type 2 diabetes and non-alcoholic fatty liver in HDL, ALT and AST variables.