Regular physical exercise has been found to reduce the risk of older people developing Alzheimer's disease, a study has shown.
The results, which can be found in the online edition of journal Neurology, show that the least active of the participants were more than twice as likely to develop Alzheimer's than the more active people.
The research involved 716 volunteers with an average age of 82 who used a device to monitor their day-to-day activity and underwent cognitive tests to measure their thinking and memory capacity.
It was shown that, after three years, 71 of the volunteers developed the disease.
Dr Aron Buchman, from Rush University Medical Centre in Chicago, said: "The results of our study indicate that all physical activities including exercise as well as other activities such as cooking, washing the dishes, and cleaning are associated with a reduced risk of Alzheimer's disease.
"These results provide support for efforts to encourage all types of physical activity even in very old adults who might not be able to participate in formal exercise, but can still benefit from a more active lifestyle."