Posted on 23rd Nov 2010 @ 9:24 AM

Those at high risk for Alzheimer's disease need to exercise, researchers at the University of Wisconsin-Milwaukee advise.

J. Carson Smith says physical activity promotes changes in the brain that may help protect against cognitive decline, especially in those individuals who carry a high-risk gene for Alzheimer's disease.

"Our study suggests that if you are at genetic risk for Alzheimer's disease, the benefits of exercise to your brain function might be even greater than for those who do not have that genetic risk," Smith says in a statement.

Functional magnetic resonance imaging indicated greater brain activation in exercising individuals at genetic risk for Alzheimer's disease -- especially in memory-related regions of the brain -- than those who exercised but were not gene carriers for the disease.

Smith and colleagues compared brain activation in four separate groups of healthy 65- to 85-years-olds. High risk individuals were those caring the apolipoprotein E-epsilon 4 allele.

Smith noted evidence already associated physical activity with maintaining lifelong cognitive function. However, most of this research has been done with healthy people, without any consideration of their Alzheimer's risk level, Smith says.

MILWAUKEE, Nov. 23 (UPI)