Recent research has suggested that exercise could help prevent against the onset of Alzheimer's disease.
Conducted by scientists at the University of Wisconsin-Milwaukee, the study found that individuals who carry a high-risk gene for the illness could make use of physical activity to protect against cognitive decline.
J. Carson Smith, an assistant professor of health studies who worked on the paper, said: "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."
The team looked at the brain activation during memory processing for four separate groups of healthy 65 to 85-year olds.
Results showed that the group of people carrying the gene who also exercised regularly showed the highest level of brain activity in the memory-related regions of the brain.
Memory uses 15 different functional regions of the brain, making it a useful test, Mr Smith explained.