It may be time to invest in a good pair of sneakers because walking now could save your brain later. A study out of the University of Pittsburgh found that older adults who were physically active suffered from less brain degradation than their sedentary peers. Subsequently, for the adults that exercised the areas of the brain that are usually associated with age-related shrinkage didn’t shrink. The subjects who walked the most had a significantly reduced risk of developing cognitive impairment and dementia.
The study consisted of 299 adults over 65 years of age, with data collected over a thirteen year period. The subjects’ physical activity levels were determined by the number of blocks they walked during a one-week period. The participants were separated into four categories based upon their amount of walking. Nine years later, MRI scans were used to detect gray matter volume. Four years after these MRI scans, the subjects were evaluated for development of cognitive impairment.
The subjects who walked the most had higher volumes of gray matter in a few areas of the brain, including the hippocampus, which controls emotion and memory. Interestingly, exercise was only beneficial to those walked the most. There were no significant differences between subjects who walked an average amount and those who barely walked at all. Factors such as race, education level, and Body Mass Index did not appear to affect the results.
There were a few limitations to the study that should be considered. First, the subjects were asked to give self-reports about their physical activity level, which could have corrupted the accuracy of the category placements. Secondly, it is impossible to conclude that lack of physical activity was wholly responsible for gray matter degradation. Although outlying factors were accounted for in the analysis, there is no way to ensure that unrecognized circumstances did not skew the outcome. Lastly, the subjects were intentionally chosen based upon a health bias, which may have resulted in a poor representation of the general population.
Despite the previously mentioned limitations, these results are validated by many other studies that produced similar results. For example, a study published in the Journals of Gerontology found that older adults who exercised had better memory, brain processing speeds, and overall functioning. Exercise has also been shown to reduce stress, fatigue, and depression.
So get walking — your brain could use the work out!