A new study says that high-risk prone individuals against cognitive decline could be protected if they have good physical activity.

Researchers at the University of Wisconsin-Milwaukee (UWM) did the study with older people with high-risk gene for Alzheimer's disease and those who didn't possess the gene.

"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," says J. Carson Smith, an assistant professor of health sciences.

While evidence already shows that physical activity is associated with maintenance of cognitive function across a life span, most of this research has been done with healthy people, without any consideration of their level of risk for Alzheimer's, says Smith.

The research was done on four groups of people with ages 65-85. Researchers used Functional magnetic resonance imaging to measure brain activation of participants while they performed a mental task.

"When a person thinks about people – for example, Frank Sinatra or Lady Gaga – that involves several lobes of the brain," explains Smith.

In the study groups of those carrying the gene, individuals who exercised showed greater brain activity in memory-related regions than those who were sedentary. The study will be published in the journal NeuroImage.

"For example, people with this increased activation might be compensating for some underlying neurological event that is involved in cognitive decline." said Smith. "Using more areas of their brain may serve as a protective function, even in the face of disease processes."