Alzheimer's DementiaElderlyExercise

Modest exercise lowers dementia risk, modestly

These findings are noteworthy considering the relatively modest amount of physical activity undertaken by study participants.

First, the details.

  • 138 adults, 50 years and older, with memory problems but not meeting the criteria for dementia were randomly assigned to education plus usual care or to a 24-week home-based physical activity program.
  • The aim: encourage at least 150 minutes of moderate-intensity physical activity per week (3, 50-minute sessions).
  • The most frequently recommended activity was walking.
  • Cognitive (reasoning) function was measured using the Alzheimer Disease Assessment Scale — Cognitive Subscale (ADAS-Cog)
    • ADAS-Cog tests reasoning ability and is popular for early cases of dementia.
  • Clinical Dementia Rating scores (a test of dementia severity) were also used.

And, the results.

  • Exercise resulted in 142 minutes more physical activity per week (20 minutes per day) than usual care.
  • The exercise group had better ADAS-Cog scores and better delayed recall (adding time between reading a list of words and repeating the list) than those getting usual care — average improvement of 0.69 points vs the usual care control group at 18 months (small but statistically significant result).
  • Participants in the physical activity group also had lower Clinical Dementia Rating scores.

The bottom line?
“Unlike medication, which was found to have no significant effect on mild cognitive impairment at 36 months, physical activity has the advantage,” concluded the authors, “of health benefits that are not confined to cognitive function alone, as suggested by findings on depression, quality of life, falls, cardiovascular function, and disability.”

Dr. Eric Larson of the Group Health Center for Health Studies, Seattle, provides context. “In addition to traditional medical approaches to prevent this dreaded disease, social factors such as providing universal education, general medical care, a suitable environment, adequate nutrition, habitual exercise, and opportunities for continued social interactions throughout the lifespan also may contribute significantly to improve well-being in late life.”

There’s no magic bullet when it comes to slowing dementia. This study showed that modest exercise results in modest benefit. Others have reported benefit with exercise too. Although the corresponding pathology in the brain associated with Alzheimer’s disease does not change.

For now, the best advice seems to be stay active and stay healthy. And if your not healthy, get treatment.

8/30/08 10:27 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.