An Australian study has found regular walking can significantly improve the memory of people over the age of 50.
In a University of Western Australia study, conducted over 18 months, 170 participants aged over 50 who felt they had memory problems were divided into two groups.
For six months, one group aimed to walk for 50 minutes three times a week or participate in other moderate exercise.
The other group continued with their usual activities.
Results revealed the exercise group completed an average of 20 minutes more daily physical activity than the control group.
The exercise group performed better on cognitive tasks and had superior delayed recall than the other group.
The landmark study has been published in the Journal of the American Medical Association.
Lead researcher, chair of old age psychiatry at the University of Melbourne, Nicola Lautenschlager, said the improved memory occurred not only during the trial but for 12 months after the end of the physical activity program.
"We have known for a long time that exercise is a great way to improve cardiovascular health, but it may be that in the future exercise can also be recommended to protect against the ageing brain," she said.
"The improvement on the memory testing was significant and it was higher than in previous drug trials with Alzheimer's medications in patients with mild cognitive impairment.
Professor Lautenschlager said she believed this was the first ever trial to demonstrate that exercise can boost memory in older adults at risk of developing conditions such as Alzheimer's.
She said brisk walking was the safest form of exercise for older people and the results suggested 20 minutes of daily exercise could possibly delay the onset of conditions such as dementia.