June 28, 2017
Need motivation to get moving? A new study shows how physical fitness at any age may be good not just for the heart but the brain as well and perhaps even help to keep Alzheimer’s disease and other forms of dementia at bay.
Earlier studies have linked activities like regular jogging, walking, gardening, yoga and ballroom dancing to a lower risk for dementia. Exercise is known to boost cardiovascular health, and what’s good for the heart is good for the brain, the thinking goes.
This new study, from researchers at the University of Kentucky College of Health Sciences, further confirmed that physical fitness correlated with greater blood flow to brain regions typically affected by Alzheimer’s disease.
“We set out to characterize the relationship between heart function, fitness and cerebral blood flow,” said Dr. Nathan Johnson, the study leader. For the study, he and his colleagues recruited 30 older men and women who ranged in age from 59 to 69. They assessed their cardiovascular fitness levels by having them complete treadmill fitness tests and ultrasound scans of the heart. Then they got brain scans to assess blood flow to parts of the brain typically affected by Alzheimer’s disease.
“When we looked at individual levels of fitness, we found that those individuals that had higher fitness levels also displayed higher levels of blood flow to areas susceptible to Alzheimer’s,” Dr. Nathan said. Better heart function, not surprisingly, was also related to more robust blood flow to these key brain regions.
Exercise helps the blood vessels stay supple throughout the body, including those that large and small vessels that carry blood to and throughout the brain. Greater blood flow means the blood is delivering more oxygen and nutrients to the neuronal cells that fuel the brain.
While the results are promising, as for previous studies, one cannot say that exercise can prevent Alzheimer’s disease at this point. But the results provide further confirmation that being physically active improves heart function and blood flow to the brain and might help with the progression of the disease.
The findings add to a growing body of evidence that exercise may cut the risk of developing Alzheimer’s disease in old age. One recent study found that whether older people swam, jogged, gardened or danced, parts of the brain that were critical for memory and thinking remained more robust than their sedentary peers. [See the alzinfo.org story, “Swim, Jog or Dance: Any Activity is Good for the Brain,” at https://www.alzinfo.org/articles/prevention/swim-jog-or-dance-any-activity-is-good-for-the-brain/]
Exercise may even be good for those in the early stages of Alzheimer’s disease. One study found that men and women suffering from early Alzheimer’s who had higher levels of physical fitness had larger brains, which is associated with better memory, compared to those with lower physical fitness levels. [See the alzinfo.org story, “Exercise May Benefit the Brain in Alzheimer’s,” at https://www.alzinfo.org/articles/prevention-and-wellness-40/ ] Another study found that walking four times a week showed benefits for the brain in older men and women with mild cognitive impairment, a type of memory loss that often precedes Alzheimer’s disease. [See the alzinfo.org story, “Walking Aids the Brain in Seniors at Risk for Alzheimer’s,” at https://www.alzinfo.org/articles/prevention/walking-aids-the-brain-in-seniors-at-risk-for-alzheimers/ ]
Alzheimer’s is a complex disease that likely depends on many factors, including advancing age and the genes you inherit. Lifestyle factors like walking and regular exercise are likely just one part of the preventive puzzle. While a daily walk around the neighborhood track won’t guarantee a physically and mentally robust old age, it may help you to look, feel and act younger.
By www.ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Marc Flajolet, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Nathan F. Johnson, Brian T. Gold, Alison L. Bailey, et al: “Cardiorespiratory fitness modifies the relationship between myocardial function and cerebral blood flow in older adults.” Neuroimage, Vol. 131, May 1, 2016, pages 126-132