Weight Training Linked to Reduced Risk of Type 2 Diabetes

A new study done by researchers at Harvard School of Public Health (HSPH) and the University of Southern Denmark have provided an additional motive for men to have toned bodies. The study claims that men who do weight training regularly may be able to reduce their risk of type 2 diabetes.

It is said that men who exercise for atleast 30 minutes a day, five days a week, cut the chance of developing the most common form of diabetes by nearly 34 percent. And if weight training is combined with aerobic exercise such as brisk walking or running, they receive extra benefits as the risk reduces by nearly 59 percent.

This study that was published online in the Archives of Internal Medicine, Aug. 6, is the first study to examine the role of weight training in the prevention of type 2 diabetes.

"Until now, previous studies have reported that aerobic exercise is of major importance for type 2 diabetes prevention," said lead author Anders Grontved, visiting researcher at the Department of Nutrition at HSPH and a doctoral student in exercise epidemiology at the University of Southern Denmark. "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."

It has been estimated that nearly 346 million people are victims of type 2 diabetes. The death toll is expected to double between 2005 and 2030 according to the World Health Organization. It is noticed that the lower and middle income countries are a target, as nearly 80 percent of the deaths occur there.

The study, by senior author Frank Hu, professor of nutrition and epidemiology at HSPH, was conducted on 32,002 men from the Health Professionals Follow-up Study from 1990 to 2008.  These participants were asked to fill in a questionnaire every two years that gave a clear picture of how much time the men spent each week on weight training and aerobic exercise. The researchers adjusted for other types of physical activity, television viewing, alcohol and coffee intake, smoking, ethnicity, family history of diabetes, and a number of dietary factors. During the study period, 2,278 new cases of diabetes among the men followed.

The findings showed that even a modest amount of weight training may help reduce type 2 diabetes risks. The researchers categorized the men according to how much weight training they did per week between one and 59 minutes, 60 and 149 minutes, and at least 150 minutes -- and found that the training reduced their type 2 diabetes risk by 12 percent, 25 percent, and 34 percent, respectively, compared with no weight training. Aerobic exercise is associated with significant benefits as well; researchers found it reduced the risk of type 2 diabetes by 7 percent, 31 percent, and 52 percent, respectively, for the three categories above.

 The results suggest that, because weight training appears to bestow significant benefits independent of aerobic exercise, it can be a valuable alternative for people who have difficulty with the latter.

According to the researchers, a further analysis is required to confirm the results of the study and to analyze whether or not the findings can be generalized for women.

"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," said Hu. "To achieve the best results for diabetes prevention, resistance training can be incorporated with aerobic exercise."