EXERCISE IN OLD AGE MAY SLOW BRAIN SHRINKING BY FOUR YEARS
Exercise in old age may slow brain shrinking by up to four years, according to preliminary study findings.
Those who did either two hours of intensive exercise per week, or seven hours of light exercise such as swimming, had bigger brains than their inactive peers.
The effect of exercise was equal to four fewer years of brain ageing, the researchers said.
The study used magnetic resonance imaging (MRI) scans to measure the brains of people with a range of activity levels, including those who were inactive to those who were very active.
The scans showed less active people had smaller brain volume.
'These results are exciting, as they suggest that people may potentially prevent brain shrinking and the effects of aging on the brain simply by becoming more active,' said study author Dr Yian Gu, of Columbia University in New York.
'Recent studies have shown that as people age, physical activity may reduce the risk of cognitive decline and dementia.
'Our study used brain scans to measure the brain volumes of a diverse group of people and found that those who engaged in the top third highest level of physical activity had a brain volume the equivalent of four years younger in brain aging than people who were at the bottom third activity level.'
The study involved 1,557 people with an average age of 75. None had dementia, but 296 people had mild cognitive impairment and 28 per cent had a genetically higher risk of Alzheimer's disease.
Participants were given physical exams, thinking and memory tests, and were asked about their daily tasks and other physical activities.
Researchers then calculated how much time and energy each person spent on those tasks and activities after dividing the cohort into three groups based on their level of activity.
Their level of activity was ranked from nothing at all, to two hours of intense exercise or seven hours of light exercise, such as walking or swimming.
Researchers then reviewed MRI brain scans of all participants and found that when compared to the people in the inactive group, those who were most active had larger total brain volume.
The results remained similar even after excluding people who had mild cognitive impairment.
'Our results add to the evidence that more physical activity is linked to larger brain volume in older people,' said Dr Gu. 'It also builds on evidence that moving your body more often throughout one's life may protect against loss of brain volume.'
The findings are to be presented at the American Academy of Neurology's 72nd Annual Meeting in Toronto, Canada, April 25 to May 1, 2020.
