Pumping Up Better Insulin Efficiency

By Rosalie Marion Bliss
December 18, 2002

Among Hispanics, diabetes prevalence is about double that of non-Hispanic whites. This month, researchers funded by the Agricultural Research Service reported results from a study involving 60 community-dwelling Latino men and women over 55 years old with an average 9-year history of type 2 diabetes.

The investigators asked half of the volunteers to serve as controls and half to undergo progressive resistance training (PRT) such as weight lifting, three times a week for 16 weeks. Prior to participation, volunteers' health was screened through an in-depth physical examination and electrocardiogram.

For the exercise group, PRT reduced the requirement for diabetes medication, reduced abdominal fat and systolic blood pressure, increased lean tissue mass and increased muscle strength, which boosted at-home physical activity.

The findings were reported in the December issue of Diabetes Care by principal investigator Carmen Castaneda Sceppa. She is a physician and acting director of the Nutrition, Physiology and Sarcopenia Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, Mass.

The results show that dosages of prescribed diabetes medications were reduced in 72 percent of exercisers, compared with the control group. Moreover, by study's end, the exercisers were closer to meeting the Surgeon General's recommendations for physical activity.

The researchers concluded that appropriately prescribed and supervised, high-intensity PRT proved feasible and effective among health-screened Hispanic older adults with type 2 diabetes. They also concluded that further studies are needed to determine the optimal intensity of PRT to produce maximal benefits while ensuring safety.

Hypoglycemic symptoms were carefully monitored and volunteers were required to follow up with their primary care physician.

ARS is the U.S. Department of Agriculture's chief scientific research agency.