Brisk walking reversed stiff arteries and boosted blood flow to the brain in people with mild memory loss, according to a new study.
The US research also reportedly found that participants who engaged in brisk walking over the course of a year performed better on tests of executive function, which are thinking skills involved in planning and decision-making.
All study participants were diagnosed with mild cognitive impairment (MCI).
Some people dropped out. Among those who stuck at it, there was no further cognitive decline reported.
Why this is a very good thing
One in five people aged 65 and over have some level of mild cognitive impairment (MCI) — slight changes to the brain that affect memory, decision-making, or reasoning skills.
Studies suggest that 10 to 20 per cent of people with MCI will quickly progress to suffering dementia, including Alzheimer’s disease.
Also, it’s been established that declining levels of blood flow to the brain, and stiffer blood vessels leading to the brain, were associated with MCI and dementia.
Studies have suggested that regular aerobic exercise may help improve cognition and memory in healthy older adults.
The experiment from the University of Texas Southwestern Medical Center (UTSW) sought to establish if there is a direct link between exercise, stiffer blood vessels, and brain blood flow.
Dr C. Munro Cullum, professor of psychiatry at UTSW and co-senior author of the study, said: “There is still a lot we don’t know about the effects of exercise on cognitive decline later in life.
“MCI 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.”
This is how they established the link
According to a statement from UTS, the researchers recruited 70 men and women, aged from 55 to 80, who had been diagnosed with MCI. Participants underwent cognitive exams, fitness tests, and brain magnetic resonance imaging scans.
Then they were randomly assigned to either follow a moderate aerobic exercise program or a stretching program for one year. The exercise program involved three to five exercise sessions a week, each with 30 to 40 minutes of moderate exercise such as a brisk walk.
In both programs, exercise physiologists supervised participants for the first four to six weeks, then had the patients record their exercises and wear a heart rate monitor during exercise.
Twenty-two people dropped out, most of them from the aerobic exercise group.
However, it was the aerobic exercise group that benefited from decreased stiffness of blood vessels in their neck, and increased overall blood flow to the brain.
The more their oxygen consumption (a marker of aerobic fitness) increased, the greater the changes to the blood vessel stiffness and brain blood flow.
Changes in these measurements were not found among people who followed the stretching program.
The participants didn’t go backwards cognitively, suggesting brisk exercise might slow decline. In fact the didn’t see “any significant changes in memory or other cognitive function” one way or the other.
This might be because “of the small size or short length of the trial”. Or it could be that arresting decline is the best that can be done. To answer this question, UTSW is already carrying out a larger two-year study.
We’ll remember to check it out.