July 30, 2013
Courtesy of the University of Maryland
and World Science staff
Moderate exercise seems to improve memory function in people at risk for Alzheimer’s disease, possibly helping to ward off symptoms of the memory-robbing illness, scientists have found.
“No study has shown that a drug can do what we showed is possible with exercise,” said study leader J. Carson Smith of the University of Maryland. The researchers studied people with a condition considered a risk factor for Alzheimer’s: mild cognitive impairment, or MCI, which signals an age-associated memory loss that’s greater than normal.
“After 12 weeks of being on a moderate exercise program, study participants improved their neural efficiency – basically they were using fewer neural [brain] resources to perform the same memory task,” said Smith. The findings are published in the Journal of Alzheimer’s Disease.
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, guided by a personal trainer. Both groups – one with MCI and the other with healthy brain function – improved their cardiovascular fitness by about 10 percent, the study found. Both also improved memory performance and showed enhanced “neural efficiency” during memory tasks.
The results were achieved with exercise consistent with the physical activity recommendations for older adults, the scientists said. These call for 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.
The exercise intervention was also found to improve word recall via a “list learning task.” In this, 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.
“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 said. The results suggest that exercise may reduce the need for over-activation of the brain to correctly remember something, he added.