This time of year, many folks like to go for a walk on the sand, boardwalk, or stick their toes in the ocean, but has it ever occurred to you that these casual walks might be related to a stronger brain?
Amanda, an older friend of mine, loves walking up to 45 minutes daily. She and I share the notion that walking is central to our continued mental health and wellbeing.
Research shows that men and women over 60 who walked frequently and briskly reported a stronger memory than those who abstained or did other activities, like stretching, tennis or dancing. The exquisite art of walking is a painless way to get the basic physical exercise we need daily, and this, in turn, helps the brain get the workout it needs. As simplistic as it sounds, getting up off our folding deck chair for a quick walk can help maximize health, but how exercise can freshen and renovate the power of the brain still needs to be understood.
Recent research indicates that the brain transforms itself, in response to a person's activity level and lifestyle. When I obtained my PhD, in 1975, we still thought the brain became inflexible after early childhood, leading to a decreased mental capacity with age. Instead, research shows humans retain lifelong function, and that exercise helps ensure this pattern, therefore the brain retains lifelong plasticity, changing as we do.
These past studies of brain plasticity generally focused on gray matter, though, which contains the celebrated little gray cells, or neurons, that create thoughts and memories. Less research has looked at white matter, the brain’s wiring. Made up mostly of fat-wrapped nerve fibers, known as axons, white matter connects neurons and is essential for brain health, but it can be fragile, thinning and developing small lesions with age, dilapidations that can be precursors of cognitive decline.
Worryingly, it also has been considered relatively static, with little plasticity, or ability to adapt much as lives change.
Recent research of white matter, using a sophisticated form of an MRI, divided volunteers into groups, one of which began a supervised program of stretching and balance training three times a week, to serve as an active control. Another started briskly walking together three times a week, for about 40 minutes. The final group took up dancing, meeting three times a week to practice line dances and group choreography.
The groups trained for six months before returning to the lab to repeat the tests from the study’s start. For many, their bodies and brains changed, the scientists found.
The walkers and dancers were aerobically fitter, as expected. More importantly, their white matter seemed renewed.
In the new scans, the nerve fibers in certain portions of their brains looked larger, and any tissue lesions shrunk. These desirable alterations were most prevalent among the walkers, who also performed better on memory tests now. The dancers, in general, did not.
Meanwhile, the members of the control group, who had not exercised aerobically, showed declining white matter health after the six months, with greater thinning and tattering of their axons and falling cognitive scores. For the exercisers, these findings “are very promising,” Dr. Burzynska said. They show that white matter remains plastic and active at whatever age, and a few brisk walks a week might be enough to burnish the tissue and slow or stop memory decline, she said.
Research indicates aerobic exercise by itself matters most for white matter health. The research is even more interesting when learning that the study participants also were past 60, and were inactive and worked out for only six months. The results offer “a strong case for getting up and moving,” for the sake of white matter.
To Consider: How might you benefit from getting out and walking for 45 minutes each day? How might you feel stronger or function more effectively if you took walking seriously? Might you be glad if you could enjoy better shape and better health?
ED. NOTE: Dr. Coche formerly practiced clinical psychology in Stone Harbor and Philadelphia. She invites responses through her website, www.cochecenter.com.