Older people with weaker muscles could be at a greater risk of developing Alzheimer's disease. Researchers from Rush University Medical Center at Chicago started following 970 older adults who had an average age of 80 at the start of the study. They were tested for a number of different things including cognitive function and muscle strength. Three-and-a-half years later 138 of the sample had developed Alzheimer's. Those with the highest levels of strength at the start of the study were 61% less likely to develop Alzheimer's than those with the weakest muscles and this was true even when body-mass index and physical activity was taken into account. The researchers thought that this could be because damage to mitochondria - which produce energy for cells - can affect cognition and muscle strength or because the decreased muscle strength could be due to stroke or other central-nervous system disorders which also play a part in causing Alzheimer's.
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