Lifelong exercise may prevent precursor to Alzheimer'sby Sea Stachura, Minnesota Public Radio
If you exercise you probably have your own reasons for doing it. Maybe you want to lose weight or work off stress. Researchers at the Mayo Clinic have found another reason for regular exercise. It reduces the likelihood you'll develop mild cognitive impairment. MCI is a precursor to Alzheimer's.
Rochester, Minn. — Reverend Bruce Buller preaches at United Methodist church in Rochester. He's a month shy of 75, and he nearly bounces down a brown padded mat at the Mayo Clinic Alzheimer's Disease Research Center.
"You just walk right down this sidewalk. I don't know what the computer is doing, but I walk like I would normally walk and that's it. You see it measures each grid, how long your step is, whether you go down heel or toe," he explains.
Researchers use the mat to measure Buller's gait. How wobbly or slowly he moves could be an indicator of Alzheimer's. Years from now they'll analyze the speed and length of his and other participants' steps to determine whether there's a correlation between how well he walks and the onset of Alzheimer's. Twelve percent of people over 70 have mild cognitive impairment. Some, but not all, later develop Alzheimer's.
He doesn't think he has the disease. In fact he cherishes what he can still do at his age.
"I preached last Sunday, which is a wonderful exercise in memory. Because I write a manuscript and then I preach, which is different from reading a manuscript," he says.
He's also well-educated and highly active in his community, and he has an absolutely sunny disposition. Research has shown that all three reduce the likelihood a person will develop Alzheimer's.
That makes obvious sense: staying social keeps the brain active and wards off depression; learning forms new neural pathways. But Mayo's research is more surprising than that. Regular exercise also reduces the risk of cognitive impairment.
Buller says he just happened to be a lifelong walker.
"I don't exercise so much now, but I used to walk everyday or almost everyday. One afternoon I went running in my blue sweats and two young women coming from children's choir practice said, 'Mommy, he's not in his robe,'" he laughs. "Then my physician would say, you must exercise 45 minutes or an hour every day and I said, look you get 15 minutes, that's all I have."
Conventional wisdom holds that when we age either the mind goes and the body follows or the body goes and the mind follows. But it might be a little of both.
Neuropsychiatrist Yonas Geda led this study on exercise and mild cognitive impairment.
"Exercise conducted between ages 50 and 65 at a frequency of about two to five times a week in moderate intensity seems to be protective against mild cognitive impairment," he says.
Researchers surveyed nearly 900 people in Olmsted County between ages 70 to 89. One hundred and twenty-eight participants had MCI, the rest tested normal. Researchers asked about participants' exercise habits in their 50s and 60s. The more often they exercised, the less likely the person was to develop the disease.
Geda says researchers also asked whether participants exercised regularly during just the the last year.
"The exercise habit a year prior to the interview was not protective against MCI," he says.
That means a lifelong commitment to regular exercise protects the brain. It could be that regular exercise produces a chemical that protects brain cells, Geda says. Or,
"Exercise might be a marker of a healthy lifestyle. A person who exercises might his her diet, a person who exercises might have a good social network," he says.
Or again it could be a combination of all three: brain chemicals, healthy living and a strong social network.
These results should be taken generally. These are statistical findings. There's no guarantee that pestering your parent or grandparent to exercise will prevent Alzheimer's.
- Morning Edition, 04/16/2008, 7:40 a.m.