MINNEAPOLIS Regular exercise could reduce the risk of contracting Alzheimer's disease, say U.S. scientists. Neurologists at Case Western Reserve University in Cleveland, Ohio, reached this conclusion following a study of 373 U.S. citizens. The result indicates that life-long, regular exercise may prevent the development of Alzheimer's disease, research team leader Arthur Smith told the 50th annual meeting of the American Academy of Neurology in Minneapolis. Participants in the study included 126 Alzheimer's patients and 247 people not suffering from the disease, a gradually progressive brain dementia.