Improvement in insulin sensitivity, but without changes in liver enzymes in obese women after 12 weeks of a walking exercise program with self-selected intensity

Background: Obesity is related to negative changes in insulin resistance and liver enzymes and is associated with the risk factor for the development of type II diabetes mellitus and nonalcoholic fatty liver disease. A number of studies have demonstrated that aerobic exercise shows promise for disease prevention and treatment in this population. Aim: The objective of the present study was to evaluate the effect of a walking exercise program with self-selected intensity on insulin resistance and liver enzymes in obese women. Methods: Forty-eight obese women (47.8 ± 8.4 years; 88.1 ± 12.0 kg; 158.0 ± 0.1 cm) were divided into two groups: control group (CG; n = 23) and self-selected walking group (SSWG; n = 25). Before and after the exercise program, all subjects underwent anthropometric measurements and blood samples were collected. The intervention consisted of a walking exercise program with self-selected intensity for 12 weeks (3 times/week, totalizing 36 sessions). Results: After the exercise program, fasting glucose, fasting insulin, and HOMA improved only in the SSWG (p < 0.05), but there were no differences between groups (p > 0.05). In addition, there were no differences in liver enzymes after the intervention in both groups (p > 0.05). Conclusions: The results support that a walking exercise program with self-selected intensity improved insulin resistance in obese women. Thus, exercise programs with self-selected intensity seem to be an interesting alternative for improving health and preventing diseases.