Moderate aerobic exercise helps boost blood flow to the brain in older women, new research reveals.
The small study included 16 women aged 60 and older who walked briskly for 30 to 50 minutes three or four times a week for three months. By the end of that time, the amount of blood flow to the brain had increased by as much as 15%.
The researchers also found that the women's VO2 max - the body's maximum capacity to transport and use oxygen during exercise - increased about 13%, their blood pressure fell an average of 4%, and their heart rates decreased about 5%.
The findings offer insight into how vascular health affects brain health, lead researcher Rong Zhang, of the Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital in Dallas, explained.
How the study was done
Zhang and the other researchers used Doppler ultrasonography to chart blood flow in the women's carotid arteries, which are located in the neck and supply the brain with crucial glucose and oxygen-rich blood. The blood also gets rid of brain metabolic wastes such as amyloid-beta protein (implicated in Alzheimer's disease) that have been released into the brain's blood vessels.
The study is scheduled for presentation at the Experimental Biology annual meeting, in Washington, DC, as part of the scientific programme of the American Physiological Society.
"There are many studies that suggest that exercise improves brain function in older adults, but we don't know exactly why the brain improves. Our study indicates it might be tied to an improvement in the supply of blood flow to the brain," Zhang said.
It's not known if increasing blood flow to the brain can help prevent Alzheimer's disease and other types of dementia but "there is strong evidence to suggest that cardiovascular risk is tied to the risk for Alzheimer's disease," Zhang said.
Because this study was presented at a medical meeting, the findings should be viewed as preliminary until they are published in a peer-reviewed journal.
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