Obesity is a risk factor of nonalcoholic fatty liver disease. Although the standard therapy for obesity involves physical exercise, well-planned studies of the changes in liver function in response to different exercise intensities in obese subjects are scarce. The aim of the present study was to examine a question of how does exercise mode affect the liver function.

44 women with abdominal obesity were randomized into two exercise groups: endurance (group A) and endurance-strength (group B). Women in each group exercised for 60min 3 times/week for a 3-month period. Markers of liver function: serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltranspeptidase (GGT), alkaline phosphatase (ALP) activities, and bilirubin levels were quantified.

We found significant differences in ALT (p<0.01) and AST (p<0.05) activities between group A and B after training exercise. Blood ALT and AST tended to decrease in group B, increase in group A. Significant reduction in serum GGT level after exercise in both groups was observed (p<0.001, group A; p<0.01, group B). Neither endurance nor endurance-strength exercise led to changes in serum ALP activity and total or direct bilirubin level. However, endurance-strength training resulted in significant decreases in serum indirect bilirubin (p<0.05). Strong positive correlations between serum indirect bilirubin and body mass (r=0.615; p=0.0085) and BMI (r=0.576; p=0.0154) were found after endurance-strength exercise (group B).

The mode of exercise does matter: endurance-strength exercise led to a greater improvement, compared to endurance exercise, in the liver function in women with abdominal obesity.