Walking 6 Miles a Week May Preserve Memory, Erickson-Led Study Says

New research shows that walking at least six miles a week may protect brain size and, in turn, preserve memory, according to a University of Pittsburgh study published in the Oct. 13 online issue of Neurology, the medical journal of the American Academy of Neurology.

“Brain size shrinks in late adulthood, which can cause memory problems,” said study author Kirk Erickson, a Pitt professor of psychology.

The study shows in cognitively normal elderly persons that a relatively easy activity like walking may be a way of staving off cognitive impairment—the stage of memory loss that comes before dementia and Alzheimer’s disease—by increasing the volume of the brain’s gray matter, which is associated with fewer memory problems.

“If regular exercise in midlife could improve brain health and improve thinking and memory in later life, it would be one more reason to make regular exercise in people of all ages a public health imperative,” said Erickson.

“Our study results suggest that walking is good for the brain and reduces the risk for future memory decline,” said Cyrus Raji, an MD/PhD candidate in Pitt’s School of Medicine and coauthor of the study.

For the study, 299 dementia-free people recorded the number of blocks they walked in one week. Nine years later, scientists took brain scans of the participants to measure their brain sizes. After four more years, the participants were tested to determine whether if they had developed cognitive impairment or dementia.

The study found that people who walked at least 72 blocks per week, or roughly six to nine miles, had greater gray matter volume nine years later than people who didn’t walk as much. Walking more than 72 blocks did not appear to increase gray matter volume any further.

By four years later, 116 of the participants had developed cognitive impairment or dementia. The researchers found that those who walked the most cut their risk of memory problems in half.

The study was supported by the National Institute on Aging.

The American Academy of Neurology, an association of more than 22,000 neurologists and neuroscience professionals, is dedicated to promoting the highest-quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating, and managing disorders of the brain and nervous system, including epilepsy, dystonia, migraine, Huntington’s disease, and dementia.