Not everyone with type 2 diabetes will benefit from exercise, according to a fresh look at past research.
Exercise is widely recommended to help prevent and manage type 2 diabetes, but as many as one in five patients may not benefit, researchers suggest.
“We now know that about 15 to 20 percent of individuals do not respond to supervised exercise interventions — at least in terms of glucose control and muscle metabolism,” said review author Lauren M. Sparks of the Sanford-Burnham Medical Research Institute in Orlando.
“But at this stage, we do not know who will and who will not respond to an exercise program.”
Regular exercise is known to help prevent and manage type 2 diabetes, in which the body's cells become resistant to insulin or not enough of the hormone is produced, so glucose builds up in the bloodstream. Along with diet and medication, an exercise program is often part of a person’s treatment plan.
In their analysis, Sparks and her colleague Natalie A. Stephens looked at both published and unpublished research showingthat a minority of individuals did not improve their glucose control after nine months of supervised exercise.Sparks said some participants used treadmills three to four days a week for nine months and still ended up no better than when they started.
“We did not intervene with their diets, and these individuals were on their prescribed medications," she said.
Sparks believes this phenomenon is rooted in genetics. She hopes more research programs committed to investigating the underlying mechanisms will identify the individuals before they begin an exercise program.