Strength Training May Aid in Type 2 Diabetes

Strength training might help women with type 2 diabetes improve their body's use of insulin, new research suggests.

In a small study of obese, postmenopausal women, investigators found that a regimen of aerobic exercise and strength training was better than aerobic activity alone when it came to improving insulin sensitivity.

Type 2 diabetes arises when the body loses sensitivity to insulin, a hormone that shuttles the sugars from food into body cells to be used for energy. Obesity is a major risk factor for insulin resistance and type 2 diabetes, and diet and exercise modification is one strategy for controlling the condition.

It's been unclear, though, whether there are added benefits from bulking up an exercise regimen with resistance training, which aims to build muscle. Such training could improve insulin sensitivity by boosting muscle mass and cutting fat stores in the body, according to the authors of the new study.

To test this idea, they randomly assigned 28 obese women to one of three groups: one that followed 16 weeks of supervised aerobic exercise and strength training; one that followed an aerobic regimen only; and one that continued with their usual diabetes care.

At the end of the study, women in both exercise groups had less abdominal fat and greater muscle mass. But only the strength-training group, which had a bigger increase in muscle density, showed improved insulin sensitivity in tests.
Darcye J. Cuff, of St. Paul's Hospital in Vancouver, Canada, and her colleagues report the findings in the November issue of Diabetes Care.

According to the researchers, the findings suggest that the changes resistance exercise produced in abdominal fat and muscle mass were behind the improvements in insulin sensitivity. Adding strength training to aerobic workouts, they conclude, might be the best exercise regimen for improving insulin resistance.