RODALE NEWS, LENOX, MA—If you’re looking for one more reason to get off the couch and get moving, here it is: There is growing evidence that aerobic exercise can help prevent, or at least forestall, the development of Alzheimer’s disease (AD). That's good news for a bit chunk of our aging population; it is estimated that 10 million baby boomers (1 in 8) will develop Alzheimer's. And even if you are an aging couch potato who is not at risk for AD, exercise can help prevent and even reverse many aspects of normal age-related memory decline.
THE DETAILS: Earlier this month, Rodale.com reported that experts at the National Institutes of Health concluded there is not enough controlled research demonstrating that any lifestyle habits can delay or prevent Alzheimer’s. We explained to you then why that's not cause to give up on lowering your AD risk. And in fact, a recent randomized, controlled study suggests that aerobic exercise can prevent, or at least forestall, the onset of Alzheimer’s in people who are at highest risk for the disease. The researchers in that study looked at a group of elderly people diagnosed with mild cognitive impairment (MCI). People with MCI perform poorly on cognitive tests, but do not show the difficulties in performing tasks of daily living that are characteristic of Alzheimer’s. MCI can be viewed as a precursor to full-blown AD; people with MCI have a five- to tenfold greater risk of progressing to Alzheimer’s.
The research, published earlier this year in the Archives of Neurology, showed that sedentary adults diagnosed with MCI who were enrolled in a six-month exercise program improved their ability to concentrate and carry out a variety of complex tasks, compared with a control group that only completed stretching activities. In fact, members of the stretching-only group declined in their performance on those same tasks during the six months of the study. Laura Baker, PhD, lead researcher on the team from the University of Washington School of Medicine in Seattle, reported that her group conducted many cognitive tests to confirm that what they were observing was real. They found improvements on all measures of executive function, the set of mental skills involved in focusing on and accomplishing complex tasks.
And that's not the only evidence for the benefits of exercise to an aging brain. Previous research done by Art Kramer, PhD, and his colleagues at the University of Illinois, found that older sedentary adults not at risk for AD who engaged in aerobic exercise experienced significant improvement in cognitive function. They found that a 5 to 7 percent improvement in cardiorespiratory fitness led to an increase of up to 15 percent on mental tests.
WHAT IT MEANS: Whether or not you are at risk for AD, exercise is good for your brain. Evidence is growing that exercise can delay, or in some cases, prevent the onset of Alzheimer’s. It is especially crucial for individuals suffering from MCI, who are at greatest risk for developing Alzheimer's. And there's good reason for the phenomenon. Exercise helps to improve cognitive function by increasing blood flow to the brain, and boosting levels of oxygen and nutrients. Exercise also promotes the production of growth factors that stimulate the birth of new brain cells, and promote their connections to other existing brain cells.
Of all the lifestyle practices studied for maintaining healthy brain function, aerobic exercise has been shown to be the most effective.