Regular exercise can delay dementia for many older adults., a study shows.

     BEIJING, Jan. 17 (Xinhuanet) -- Regular exercise can delay dementia for many older adults, and the frailest may benefit most, according to a new study led by Seattle researchers.

    Light activity such as walking for 15 minutes seemed to reduce 30 to 40 percent risk of dementia among healthy people over age 65, the researchers report in Tuesday's issue of the Annals of Internal Medicine.

    Those who were the frailest at the start of the study showed the most benefit, meaning people really should "use it after you start to lose it," to slow age-related problems in thinking, said Dr. Eric Larson, the study's lead author.

    "What is striking is that it didn't take much to reduce the risk ... If you don't exercise, you should start. It's never too late," he said, after conducting the most definitive studies on the relationship between dementia and exercise.

    The study, from 1994 to 2003, followed 1,740 people ages 65 and older who showed no signs of dementia on tests of mental function at the start of the study. The participants' health was evaluated every two years for six years.

    No signs of dementia were found in 1,185 people, 77 percent of whom said they exercised three or more times a week. Among the 158 people with signs of dementia, 67 percent said they did not exercise regularly.

    Some researchers have theorized that exercise might reduce brain levels of amyloid, a sticky protein that clogs the brain in Alzheimer's patients.

    Besides walking or swimming, participants in the study also did bicycling, aerobics, weight training, stretching and other exercises. Enditem

    (Agencies)