A U.S. study revealed that exercise and being physically fit can control Alzheimer’s disease. The study, published in Neurology found that people with Alzheimer’s over the age of 60, who were not physically fit, had four times the signs of brain shrinkage than their fitter counterparts.

Brain volume is one of the ways the severity of Alzheimer’s is mapped and Dr. Jeffrey Burns, director of the Alzheimer's and Memory Program at the University of Kansas School of Medicine in Kansas City, said his was one of the first studies to establish a link between exercise and the progress of the illness. Earlier studies focused on exercise reducing the disease onset.

He said, "People with early Alzheimer's disease may be able to preserve their brain function for a longer period of time by exercising regularly and potentially reducing the amount of brain volume lost. Evidence shows decreasing brain volume is tied to poorer cognitive performance, so preserving more brain volume may translate into better cognitive performance."

The study brought out three possible scenarios, the first that cardio respiratory fitness affects brain atrophy in relation to Alzheimer's disease; secondly Alzheimer's process affects fitness; and some, currently unknown factor links Alzheimer's-related brain atrophy and physical fitness.

"The people with higher fitness levels had larger brains, and there was a strong correlation between the two," Burns explained. "We're limited because of the study design, but it could suggest that maintaining fitness may have a beneficial effect on the Alzheimer's disease process. We didn't find fitness to be associated clearly with cognitive performance, but that may be, because we need to study more people or the cognitive performance measures may not be sensitive enough," he added.

An estimated 700,000 people have Alzheimer’s in U.K and the numbers quick growth is predicted as the population ages. Susanne Sorensen, head of research at the Alzheimer's Society, said, "Exercise increases blood flow to the brain, delivering oxygen and nutrients to brain cells. This is one possible explanation why dementia progresses slower in people who are physically fit. Exercise also reduces your risk of developing dementia so it's important to take regular exercise. A healthy heart means a healthy brain."