A March 2021 study by the University of Texas Southwestern reports,

"This is part of a growing body of evidence linking exercise with brain health," 

"We've shown for the first time in a randomized trial in these older adults that exercise gets more blood flowing to your brain."

"There is still a lot we don't know about the effects of exercise on cognitive decline later in life," 

“[mild cognitive impairment] and dementia are likely to be influenced by a complex interplay of many factors, and we think that, at least for some people, exercise is one of those factors."

"There are likely some people who benefit more from exercise than others," 

"But with the sample size in this study, it was hard to analyze subgroups of people to make those conclusions."

"Having physiological findings like this can also be useful for physicians when they talk to their patients about the benefits of exercise,”

"We now know, based on a randomized, controlled trial, that exercise can increase blood flow to the brain, which is a good thing."