Exercise May Help Prevent Alzheimer's Disease
Exercise may improve cognitive function in people at risk for Alzheimer's disease, according to a new study.
Researchers found that exercise helps improve efficiency of brain activity associated with memory.
While some memory loss is normal as people age, a diagnosis of mild cognitive impairment (MCI) indicates more substantial memory loss and a greater risk for Alzheimer's disease.
Lead researcher Dr. J. Carson Smith of the University of Maryland said the latest findings provide new hope for older people diagnosed with MCI.
Smith and his team found that an exercise intervention with older adults with mild cognitive impairment improved memory and brain function.
"We found that after 12 weeks of being on a moderate exercise program, study participants improved their neural efficiency -- basically they were using fewer neural resources to perform the same memory task," Smith said in a news release. "No study has shown that a drug can do what we showed is possible with exercise."
In the study, two groups of physically inactive older adults aged 60 to 88 years old were put on a 12-week exercise program that focused on regular treadmill walking.
Both adults with MCI and those with healthy brain function improved their cardiovascular fitness by about 10 percent at the end of the intervention. More importantly, both groups also improved their memory performance and showed enhanced neural efficiency while engaged in memory retrieval tasks.
To measure the effect exercise has on brain health and memory, researchers had study participants identify famous names and measured their brain activation while engaged in correctly recognizing a name like Frank Sinatra or other celebrities well known to adults born in the 1930s and 40s.
"The task gives us the ability to see what is going on in the brain when there is a correct memory performance," Smith explained.
Brain scans taken after the exercise intervention showed a significant decrease in the intensity of brain activation in eleven brain regions while participants correctly identified famous names. Researchers said that the brain regions that showed improved efficiency corresponded to those involved in the pathology of Alzheimer's disease, including the precuneus region, the temporal lobe, and the parahippocampal gyrus.
The exercise intervention was also helped improve word recall in a list-learning task.
"People with MCI are on a very sharp decline in their memory function, so being able to improve their recall is a very big step in the right direction," Smith explained.
Smith said the findings suggest that exercise may reduce the need for over-activation of the brain to correctly remember something.