People can lower their chances of getting Alzheimer's disease by taking a brisk stroll daily, according to scientists.
A team at the University of Nottingham has found that a stress hormone produced during a brisk stroll can protect the brain from memory loss, the Mirror reported.
The finding, published in the Journal of Alzheimer's Disease, may also explain why people vulnerable to stress are at more risk of dementia.
Experts have been mystified why higher physical and mental activity can lower your chances of getting Alzheimer's.
But the Nottingham University team has suggested that the key might be found in balancing the body's level of the hormone CRF.
People with Alzheimer's have a reduced level. But normal levels of CRF help the brain, keeping the mental faculties sharp.
The new research look into the effects of CRF in mice and found when its production was blocked, the mice displayed stress and abnormal behaviour.
Dr Marie-Christine Pardon and her team found releasing CRF can maintain a connection between nerve cells, which is thought to break down in the Alzheimer's patients and cause early memory loss.
Other symptoms include mood changes and problems with communicating and reasoning.
This is the first time researchers have been able to identify a brain process directly responsible for the beneficial effects of exercise in slowing down the progression of the early memory decline of Alzheimer's, Dr Pardon said.
Further the research suggests that a healthy lifestyle involving exercise slows down Alzheimer's risk, she added.