Older adults at risk for getting diabetes who took a 15-minute walk after every meal improved their blood sugar levels, a new study shows.

Three short walks after eating worked better to control blood sugar levels than one 45-minute walk in the morning or evening, said lead researcher Loretta DiPietro, chairwoman of the George Washington University School of Public Health and Health Services in Washington, D.C.

"More importantly, the post-meal walking was significantly better than the other two exercise prescriptions at lowering the post-dinner glucose level," DiPietro added.

The after-dinner period is an especially vulnerable time for older people at risk of diabetes, DiPietro said. Insulin production decreases, and they may go to bed with extremely high blood glucose levels, increasing their chances of diabetes.

About 79 million Americans are at risk for type 2 diabetes, in which the body doesn't make enough insulin or doesn't use it effectively. Being overweight and sedentary increases the risk. DiPietro's new research, although tested in only 10 people, suggests that brief walks can lower that risk if they are taken at the right times.

The study did not, however, prove that it was the walks causing the improved blood sugar levels.

The research is published June 12 in the journal Diabetes Care.

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