Keeping fit could help slow the progress of Alzheimer's disease according to researchers at the University of Kansas. 121 people aged 60 and over took fitness tests on a treadmill and had brain scans to measure their white matter, grey matter and total brain volume. 57 of the group were in the early stage of Alzheimer's disease while the rest were unaffected. Physical fitness had no effect on the brain in the healthy group but in those with early Alzheimer's people who were unfit had four times more brain shrinkage than fitter people.
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