Ernest R. Greene, PhD
Ernest R. Greene, PhD, New Mexico Highlands University, Las Vegas, coauthor of study titled “Acute Effects of Walking on Human Internal Carotid Blood Flow,” published in FASEB Journal.
Only thoughts reached by walking have value. Friedrich Nietzsche
For a sharper brain, put your best foot forward. Actually, put either foot forward. Repeatedly.
The physical act of putting your foot on the ground, the impact of your foot, sets in motion a rhythmic response in your cardiovascular system that stimulates beneficial blood flow to the brain, according to a new scientific discovery.
Background: Oxygen is the brain’s fuel. Although the brain represents only 2% of an average person’s body weight, it uses 20% of the body’s oxygen. No wonder optimal brain function relies on robust blood flow—aka, cerebral blood flow (CBF)—to deliver oxygen. Optimal CBF is necessary to meet the brain’s metabolic demands and to regulate blood pressure inside the brain. Until recently, CBF was thought to be a constant thing, unrelated to the ups and downs of blood pressure as it changes during, for example, exercise. Then researchers at New Mexico Highlands University in Las Vegas found that vigorous running stimulated CBF. They wondered if everyday walking had a similar effect.
Study: The research team studied 12 healthy young adults, either standing at rest or walking at an easy stride—a little over two miles an hour. They used ultrasound to measure blood flow in the carotid artery, the major conduit of oxygenated blood to the brain.
Finding: Each time the foot hits the ground, it sends a subtle rhythmic pulse upward through the arteries, a kind of blood pressure “wave” that can dynamically increase blood flow to the brain by about 10% to 20%. With walking, the effect isn’t as strong as with running—that’s 20% to 50%—but it’s significant. The retrograde pressure effect doesn’t happen at all with nonimpact aerobic exercise (cycling), according to earlier research by the same group.
Bottom Line: If you love cycling…or swimming or other nonimpact aerobics…by all means keep at it—regular aerobic exercise of any kind is good for the cardiovascular system and brain health, and can help protect against dementia. Strength training is brain-healthy too. But there is something specific to walking and running that helps regulate the brain’s blood flow. The rhythmic foot impact, the authors speculate, may optimize blood flow to the brain and thus improve brain function—which may in turn improve one’s overall sense of well-being, and could possibly translate into helping to prevent vascular dementia. The next time your mind is foggy, try a walk around the block to get the blood moving to your brain. Wearing thin-soled shoes will give you a stronger pulse—and help increase your bone density! Even better—start a walking book club.
