Brisk Walking Routine Sharpens Memory As We Age

Seniors who routinely take brisk walks can boost their brain power for better memory function. The results of a new study have shown that seniors who walked briskly at least three times weekly not only achieved better results on memory tests, but also increased the size of their hippocampus, an area of the brain associated with memory. The study was recently published online in the Proceedings of the National Academy of Sciences.

The findings suggest that with simple moderate exercise, loss of brain volume in the aging can be delayed and possibly even reversed. Because brain shrinkage is linked to memory impairment in the elderly, exercise could play a role in preventing dementia. According to lead study author Kirk Erickson, an assistant professor of psychology at the University of Pittsburgh, “It's possible that exercise could help ward off not only ordinary mental decline but also dementia.”

Regarding the results of the study, Erickson pointed out, “We can change the brain in older adults.” He went on to explain, “It's amazing that a one-year period of moderate exercise isn’t just slowing down the atrophy, it’s actually reversing it.”

For their study, a team of researchers from the University of Pittsburgh, University of Illinois, Rice University, and Ohio State University enrolled 120 sedentary adults having an averaging in age from their middle to late sixties. The subjects were divided into two groups. One group got their aerobic exercise by walking for 40 minutes, three times weekly, while the other group participated only in stretching and toning exercises.

Findings showed that both groups performed better on a test of spatial memory, relating to how the brain stores information regarding the location of physical objects in space (the environment around you). However, the most memory improvement was seen in the aerobic exercise group.

After one year, MRI brain scans showed that those study participants on the walking program had gained about 2 percent in the size of the hippocampus. According to the researchers, this is the equivalent of one-to-two years of reversal in age-related brain shrinkage since the hippocampus shrinks by about 1 to 2 percent a year in otherwise healthy adults. (The shrinkage occurs even more rapidly among people with dementia). In comparison, the stretching group experienced a decrease in hippocampal volume of about 1.4 percent.

Subjects who demonstrated the greatest improvements in memory also had the largest increases in hippocampal volume. In addition, findings showed that those with the biggest volume increase in the hippocampus also had higher levels of the brain-derived neurotrophic factor in the blood that is associated with brain health.

The findings of the study bring to mind that if three days of moderate exercise weekly is promising for memory health, would exercising six days weekly be of even more benefit? Erickson’s reply to the question is: “We really don't have a good answer for that,” at least not yet. His previous research showed that older adults who walked between six and nine miles weekly experienced significantly less decrease in brain volume over a nine year period compared to those who got little exercise. However, the increased amount of walking had no effect on an increase of brain volume.

The researchers concluded that the study results “clearly indicate that aerobic exercise is neuroprotective and that starting an exercise regimen later in life is not futile for either enhancing cognition or augmenting brain volume.” The possibility exists that additional benefits could come from getting an early start. It’s well known that a good exercise program is beneficial to your overall health. Now would be a good time to start your own fitness and exercise program to help boost your memory and preserve your general health.