Exercise may be the best medicine

For Alzheimer’s disease and cognitive function

New research out of the University of Maryland School of Public Health shows that exercise may improve cognitive function in those at risk of Alzheimer’s by improving the efficiency of brain activity associated with memory. Memory loss leading to Alzheimer’s disease is one of the greatest fears among older people. While some memory loss is normal and to be expected as we age, a diagnosis of mild cognitive impairment or MCI, signals more substantial memory loss and a greater risk of Alzheimer's for which currently there is no cure.

The study provides new hope for those diagnosed with MCI and is the first to show that an exercise intervention with older adults with mild cognitive impairment (average age 78) improved not only memory recall but also 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,” says Dr. smith. No study has shown that a drug can do what we showed is possible with exercise.

Recommended daily activity: Good for the body, good for the brain
Two groups of physically inactive older adults (ranging from 60-88 years old) were put on a 12 week exercise program that focused on regular treadmill walking and was guided by a personal trainer. Both groups - one which included adults with MCI and the other with healthy brain function - improved their cardiovascular fitness by about ten percent at the end of the intervention.

More notably, both groups also improved their memory performance and showed enhanced neural efficiency while engaged in memory retrieval tasks.

The good news is that these results were achieved with a dose of exercise consistent with the physical activity recommendations for older adults. These guidelines urge moderate intensity exercise (activity that increases your heart rate and makes you sweat, but isn’t so strenuous that you can’t hold a conversation while doing it) on most days for a weekly total of 150 minutes (eg. 30 minutes, 5 times a week).

Measuring exercise impact on brain health and memory
One of the first observable symptoms of Alzheimer’s disease is the inability to remember familiar names. The study had participants identify famous names and measured their brain activation while engaged in correctly recognizing a name - eg. Frank Sinatra or other celebrities well known to adults born in the 1930’s and 1940’s. “The task gives us the ability to see what is going on in the brain when there is a correct memory performance” Dr Smith explains.

The exercise intervention was also effective in improving word recall via a “list learning task” i.e. when people were read a list of 15 words and asked to remember and repeat as many words as possible on five consecutive attempts, and again after a distraction of being given another list of words.

The results of the study suggest that exercise may reduce the need for over-activation of the brain to correctly remember something.

Dr. Smith has plans for a larger study that would include more participants, including those who are healthy but have a genetic risk of Alzheimer’s and follow them for a longer time period with exercise in comparison to other types of treatments. He and his team hope to learn more about the impact of exercise on brain function and whether it could delay the onset or progression of Alzheimer’s disease.

Semantic Memory Functional MRI and Cognitive Function after Exercise Intervention in Mild Cognitive Impairment. Smith JC, Nielson KA, Antuono P, Lyons JA, Hanson RJ, Butts AM, Hantke NC, Verber MD. Journal of Alzheimer's Disease, 2013, DOI: 10.3233/JAD-130467 Published by IOS Press. First published: 29 July 2013.