Walking briskly on a regular basis may be more effective than vigorous jogging for helping prevent diabetes, a new study finds.

Pre-diabetes is a condition in which a person’s blood sugar (glucose) is abnormally high but not elevated enough to warrant a diagnosis of diabetes. Generally, though, if measures are not taken, pre-diabetes may progress to full-blown diabetes.

Researchers at Duke Health in Durham, N.C., performed a six-month study of 150 people, each of whom was designated as having pre-diabetes based on elevated fasting glucose levels.

Study participants were randomized into four groups. The first group followed an intervention modeled after the Diabetes Prevention Program (DPP).  Considered the gold standard of diabetes prevention, this program requires cutting calories, eating a low-fat diet, and exercising. Study participants in this group adopted the diet changes, and performed moderate-intensity exercise equivalent to 7.5 miles of brisk walking in a week.

Other study participants were randomly assigned to receive exercise only, using different amounts and intensities: low-amount at moderate intensity (equivalent to walking briskly for 7.5 miles per week); high-amount at moderate intensity (equivalent to walking briskly for 11.5 miles per week); and high-amount at vigorous intensity (equivalent to jogging for 11.5 miles per week).

“We know the benefits of lifestyle changes from the DPP, but it is difficult to get patients to do even one behavior, not to mention three so we wanted to know how much of the effect of the DDP could be accomplished with exercise alone,” says Dr. William Kraus, the study’s lead author.

On average, participants in the DPP group had the greatest benefit, with a 9 percent improvement in oral glucose tolerance -- a key measure of how readily the body processes sugar and an indicator used to predict progression to diabetes.

One of the exercise-only groups came in a close second. Participants in the moderate-intensity, 11.5-mile group saw a 7 percent improvement in glucose tolerance on average. The moderate-intensity, 7.5-mile group had a 5 percent improvement on average.

But the lowest improvement was seen among those in the vigorous-intensity, 11.5-mile group, with only a 2 percent average improvement.

“When faced with the decision of trying to do weight loss, diet, and exercise versus exercise alone, the study indicates you can achieve nearly 80 percent of the effect of doing all three with just a high amount of moderate-intensity exercise,” adds Kraus of the study’s findings, which appear in Diabetologia.