Researchers from the University of Melbourne, Australia, found that people who participated in a home-based physical activity program, experienced a modest improvement in their cognitive function (i.e memory , problem solving). However, according to an editorial published in the Journal of the American Medical Association, the problem with the study was that although the benefits showed in the tests, "neither patients, family members, nor clinicians could easily detect that level of difference, despite its statistical significance," said author Eric B. Larson, MD.
Nicola T. Lautenschlager, M.D., and colleagues studied a group of 138 adults, aged over 50, who were reporting memory problems but who did not meet the criteria for a diagnosis of dementia. The participants were randomly allocated to different groups that involved either education, usual care, or a 24 week activity program. Their cognitive function was assessed using the Alzheimer Disease Assessment Scale-Cognitive Subscale, ADAS-Cog, over 18 months. When evaluated, the physical activity group scored higher in the ADAS-Cog test, in delayed recall tests and had lower Clinical Dementia Rating scores than those in the usual care group.
The physical activity group was asked to undertake three 50-minute sessions each week of moderate-intensity. Most of the participants were recommended walking as their activity. This resulted in them doing 142 minutes more physical activity a week than the usual care group. Lautenschlager and her team, reported that the benefits from the physical activity program were apparent after 6 months and continued for a further 12 months after the program finished.
An editorial in the same edition of JAMA highlights numerous studies where it has been shown that exercise has many preventative and treatment health benefits, not just to do with cognition, but also for depression, cardiovascular function, falls and disability. How effective physical exercise is in the prevention and treatment of Alzheimer's disease has been difficult to evaluate because of these cross over improvements that can be seen people's overall heath.
Article Source: JAMA, September 3, 2008-Vol 300, No. 9
Further information about exercise and Alzheimer's disease can be found:
Exercise May Cut Dementia Risk