A new review from The Cochrane Library, based on six trials involving 289 people, has concluded that exercise can improve cognition and the ability of older people with dementia to carry out daily activities, such as walking short distances or getting up from a chair. However, there was no clear effect of exercise on depression in older people with dementia, and the reviewers say that more evidence is needed to understand how exercise could reduce the burden on family caregivers and health systems.
http://www.eurekalert.org/pub_releases/2013-12/w-ebf120313.php
Reference:
Forbes D, Thiessen EJ, Blake CM, Forbes SC, Forbes S. Exercise programs for people with dementia. Cochrane Database of Systematic Reviews 2013, Issue 12. Art. No.: CD006489. DOI: 10.1002/14651858.CD006489.pub3.