Exercise may help to prevent cognitive decline

Thrice weekly sessions of moderate-intensity exercise may help to ward off cognitive decline in people at risk of developing Alzheimer's disease.

Researchers from the University of Melbourne studied the effect of a physical activity program on 138 people aged 50 and over with mild cognitive impairment. Participants were randomly assigned to either an exercise group or a control group. Those assigned to the exercise group were asked to exercise three times a week at moderate-intensity for 50 minutes, for 24-weeks. Walking was the exercise of choice in virtually all of the participants.

Results at the end of the 24-week-long exercise period showed that people in the exercise group achieved better scores in tests of their cognitive function, and lower scores in tests identifying signs of dementia. These benefits were found to persist for at least 12-months after patients had stopped taking part in the exercise program.

The authors concluded: "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."

Lautenschlager NT, Cox KL, Flicker L, Foster JK, van Bockxmeer FM, Xiao J, Greenop KR, Almeida OP. Effect of Physical Activity on Cognitive Function in Older Adults at Risk for Alzheimer Disease. JAMA. 2008;300:1027-1037.