Exercise May Help Improve Memory

(September 3, 2008) - Exercise is good for the body. It may also be good for the brain. Adults with memory problems who participated in a home-based physical activity program experienced a modest improvement in cognitive function, compared to those who did not participate in the program, according to a study in the Journal of the American Medical Association. .

As the world population ages, the number of older adults living with Alzheimer disease (AD) is estimated to increase from the current 26.6 million to 106.2 million by 2050. (Read about "Alzheimer's Disease") "If illness onset could be delayed by 12 months, 9.2 million fewer cases of AD would occur worldwide. For this reason, attempts have been made to identify individuals who are at increased risk of AD and to test interventions that might delay the progression of early non-specific symptoms to full-blown dementia," the authors write. (Read about "Dementia")

Researchers conducted a randomized controlled trial to test whether a physical activity intervention would reduce the rate of cognitive decline among 138 adults age 50 years and older at increased risk of dementia. The participants, who reported memory problems but did not meet criteria for dementia, were randomly allocated to an education and usual care group or to a 24-week home-based program of physical activity.

The aim of the intervention was to encourage participants to perform at least 150 minutes of moderate-intensity physical activity per week, which participants were asked to complete in three 50-minute sessions each week. The most frequently recommended type of activity was walking. (Read about "Walking for Health") The intervention resulted in 142 minutes more physical activity per week or 20 minutes per day than with usual care.

Cognitive function was assessed over 18 months. The researchers found that by study end, participants in the exercise group had better cognitive scores and delayed recall than those in the usual care control group. Participants in the physical activity group also had lower dementia scores than those in the usual care group.

"To our knowledge, this trial is the first to demonstrate that exercise improves cognitive function in older adults with subjective and objective mild cognitive impairment. The benefits of physical activity were apparent after 6 months and persisted for at least another 12 months after the intervention had been discontinued," the authors write.

"Unlike medication, which was found to have no significant effect on mild cognitive impairment at 36 months, physical activity has the advantage 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." (Read about "Depressive Illnesses" "Accidental Falls" "The Heart & Cardiovascular System")