Boston, MA – Men who do weight training
regularly—for example, for 30 minutes per day, five days per week—may be able to reduce their risk
of type 2 diabetes by up to 34%, according to a new study by Harvard School of Public Health (HSPH)
and University of Southern Denmark researchers. And if they combine weight training and aerobic
exercise, such as brisk walking or running, they may be able to reduce their risk even further—up
This is the first study to examine the role
of weight training in the prevention of type 2 diabetes. The results suggest that, because weight
training appears to confer significant benefits independent of aerobic exercise, it can be a
valuable alternative for people who have difficulty with the latter.
The study will be published online in
Archives of Internal Medicine on August 6, 2012.
“Until now, previous studies have reported
that aerobic exercise is of major importance for type 2 diabetes prevention,” said lead author
Anders Grøntved, visiting researcher in 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
Type 2 diabetes is a major public health
concern and it’s on the rise. An estimated 346 million people worldwide have type 2 diabetes, and
diabetes-related deaths are expected to double between 2005 and 2030, according to the World Health
Organization. More than 80% of these deaths occur in low- and middle-income
The researchers, including senior author
Frank Hu, professor of nutrition and epidemiology at HSPH, followed 32,002 men from the Health
Professionals Follow-up Study from 1990 to 2008. Information on how much time the men spent each
week on weight training and aerobic exercise came from questionnaires they filled out every two
years. 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, there were 2,278 new cases of diabetes among the men
The findings showed that even a modest
amount of weight training may help reduce type 2 diabetes risk. The researchers categorized the men
according to how much weight training they did per week—between 1 and 59 minutes, between 60 and
149 minutes, and at least 150 minutes—and found that the training reduced their type 2 diabetes
risk by 12%, 25%, and 34%, respectively, compared with no weight training. Aerobic exercise is
associated with significant benefits as well, the researchers found—it reduced the risk of type 2
diabetes by 7%, 31%, and 52%, respectively, for the three categories
The researchers also found that the
combination of weight training and aerobic exercise confers the greatest benefits: Men who did more
than 150 minutes of aerobics as well as at least 150 minutes of weight training per week had a 59%
reduced risk of type 2 diabetes.
Grøntved said that further research is
needed to confirm the results of the study as well as to analyze whether or not the findings can be
generalized to 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
Other HSPH authors included Eric Rimm,
associate professor in the Departments of Epidemiology and Nutrition, and Walter Willett, Frederick
John Stare Professor of Epidemiology and Nutrition and chair of the Department of
Support for the study was provided by the
National Institutes of Health (DK58845 and CA55075).
“A Prospective Study of Weight Training and
Risk of Type 2 Diabetes Mellitus in Men,” Anders Grøntved, Eric B. Rimm, Walter C. Willett, Lars B.
Andersen, Frank B. Hu, Archives of Internal Medicine, online August 6,