More Evidence That Exercise Helps Fight Diabetes

MONDAY, Aug. 6 (HealthDay News) -- People with diabetes who boost their level of physical activity can reduce their risk of premature death, according to a new study.

And a separate study found that weight training alone may reduce the risk of developing diabetes in the first place.

The first study, which involved nearly 6,000 people with diabetes, found that those who were moderately physically active had the lowest risk of death.

Leisure-time physical activity -- such as biking, gardening and housework as well as walking -- was also associated with lower risk of death, found researcher Diewertje Sluik of the German Institute of Human Nutrition Potsdam-Rehbrucke, and colleagues.

In the other study, which included more than 32,000 men, researchers found weight training alone -- without aerobics -- can help prevent type 2 diabetes, possibly by increasing muscle mass and improving insulin sensitivity.

However, a combination of weight training and aerobic exercise provided the most preventive benefit.

Both studies were published online Aug. 6 in the journal Archives of Internal Medicine.

"Until now, previous studies have reported that aerobic exercise is of major importance for type 2 diabetes prevention," Anders Grontved, lead author of the weight-training study, said in a Harvard news release.

"But many people have difficulty engaging in or adhering to aerobic exercise. These new results suggest that weight training, to a large extent, can serve as an alternative to aerobic exercise for type 2 diabetes prevention," added Grontved, a visiting researcher at the Harvard School of Public Health and a doctoral student in exercise epidemiology at the University of Southern Denmark.

Using information on participants' weekly weight training and aerobic exercise habits from 1990 to 2008, the researchers found that men who weight train on a regular basis could reduce their risk for type 2 diabetes by up to 34 percent.

Even a small amount of weight training helped. Men who lifted weights for just up to 59 minutes a week reduced their risk for diabetes by 12 percent.

Meanwhile, weight training for 60 to 149 minutes reduced the risk for type 2 diabetes by 25 percent and the men who lifted for at least 150 minutes reduced their risk by 34 percent, the investigators found.

"This study provides clear evidence that weight training has beneficial effects on diabetes risk over and above aerobic exercise, which are likely to be mediated through increased muscle mass and improved insulin sensitivity," study senior author Frank Hu, a professor of nutrition and epidemiology at Harvard, said in the news release. "To achieve the best results for diabetes prevention, resistance training can be incorporated with aerobic exercise."

The men who engaged in aerobic exercise for up to 59 minutes weekly reduced the risk of type 2 diabetes by 7 percent. Between 60 and 149 minutes of aerobics reduced risk by 31 percent, and at least 150 minutes of aerobic exercise reduced their risk by 52 percent, according to the report.

The combination of weight training and aerobic exercise was the most beneficial, the researchers said. Men who did more than 150 minutes of aerobics as well as at least 150 minutes of weight training per week had a 59 percent lower risk for type 2 diabetes.

The study authors said more research is needed to confirm these findings and determine if they apply to women as well as men.