Here are reasons to step up your activity level: Scientists have found that high-intensity exercise may protect against stroke and dementia, as well as impaired mobility and falls. A study in the June 8, 2011, online edition of Neurology suggests that performing moderate to vigorous activity such as

  • bicycling,
  • swimming,
  • jogging,
  • hiking and
  • playing tennis and racquetball
can lower your risk of "silent" stroke.

It's estimated that about 10 percent of middle-aged and older adults in the United States have had a silent stroke—with many of them unaware of it. Silent stroke, known as silent cerebral infarction (SCI), can damage your brain even though it's symptomless.

You won't experience common stroke symptoms such as sudden numbness or weakness (especially on one side of the body), speech problems, severe headache and dizziness. SCIs occur when blood flow in the arteries to the brain is interrupted and cause tissue damage. They leave small lesions in the brain that can be detected only by magnetic resonance imaging (MRI).

People with lesions have a higher risk of ischemic stroke (a stroke caused by a clot that blocks a blood vessel to the brain) and mental decline.

By exercising intensely, you may be able to ward off SCIs, say researchers. Investigators studied 1,238 older adults, 21 percent of whom said they regularly engaged in intense activity. Thirty-six percent got regular light exercise, and 43 percent didn't exercise at all.

Six years later, the researchers took MRI scans of participants' brains and found 16 percent of those tested had experienced SCIs. But the high-intensity exercisers were much less likely to have SCIs than their less active counterparts.

That doesn’t mean your activity should be all or nothing. Other studies show that you can still lower your stroke and heart disease risk—albeit to a lesser extent than intense exercise does—by doing activity such as walking, dancing, golfing or bowling. The American Heart Association recommends a combined 150 minutes of moderate intensity a week or 75 minutes of vigorous intensity a week.

And if you do decide to play hard, don't start suddenly, especially if you’ve been inactive. Speak with your doctor first.

Source: Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50

Publication Review By: the Editorial Staff at

Published: 08 Jul 2013

Last Modified: 08 Jul 2013