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FITNESS: Walking might keep mind sharp, ward off Alzheimer's
CHICAGO - The health
benefits of regular walking may include helping prevent mental decline and
Alzheimer's disease, research in patients aged 70 and up has found, bolstering
evidence that exercise needn't be strenuous to be good for you. There's plenty of evidence that mental exercise, such
as crossword puzzles and reading, may reduce Alzheimer's risks, but previous
studies on brain benefits from physical exercise had conflicting results. The new findings, contained in two studies, clarify how
much exercise might be beneficial and are good news for older people who want to
avoid mental decline but "don't like doing all that awful, sweaty
stuff," said Bill Thies, vice president for medical and scientific affairs
of the Alzheimer's Association. "This just says, `Go for a walk'" and
bolsters evidence that what's good for the heart may be good for the brain, said
Thies, who was not involved in the research. "Keep eating your veggies, too" could be
another mantra, according to a Dutch study, showing that Europeans ages 70 to 90
who ate a Mediterranean-style diet rich in fruits, vegetables, fish and olive
oil had a 23 percent lower risk of death during a 10-year follow-up than those
with less healthy eating habits. A 65 percent lower mortality risk was found in those
who combined the Mediterranean-style diet with three other healthy habits -
moderate alcohol use, no smoking and a half-hour or more per day of physical
activity, including walking. The studies appear in Wednesday's Journal of the
American Medical Association. "This study is important because it is often
thought that diet, alcohol, physical activity and smoking doesn't matter anymore
in old age," said nutrition researcher Kim Knoops of The Netherlands'
Wageningen University, who led the diet study. While the studies involved older patients, they don't
answer whether adopting healthy habits late in life has the same benefits as a
lifetime of healthy behavior, since participants weren't asked how long they'd
engaged in the activities. One of the exercise studies involved 2,257 retired men
in Hawaii ages 71 to 93. Those who walked less than a quarter-mile a day were
almost twice as likely to develop Alzheimer's or other forms of dementia as men
who walked more than two miles daily. Walking was "probably representative of a lifetime
behavior" for most of the men, given Hawaii's exercise-friendly climate,
said University of Virginia biotstatistician Robert Abbott, the lead author. A similar study, involving 16,466 female nurses ages 70
to 81, found that even women who walked a leisurely 1 1/2 hours a week did
better on tests of mental function than less active women. "We were a bit surprised that something so modest
as walking would be associated with apparent cognitive benefits," said
study author Jennifer Weuve, a Harvard School of Public Health researcher. Thies offered some possible theories for how exercise
might boost brain function. He said research in mice has suggested that exercise
might reduce brain levels of amyloid, a sticky protein that clogs the brain in
Alzheimer's patients. Also, Thies said, studies have shown that exercise boosts
levels of hormones necessary for nerve cell production, and increases blood flow
to the brain. |