The researchers carried out MRI brain scans in volunteers later in life to look for signs of poorer brain health including the presence of a type of brain damage known as cerebrovascular lesions and brain shrinkage.
Scientists linked high levels of mid-life physical activity, over 150 minutes per week with better brain health in later life. This included fewer cerebrovascular lesions in late life.
Dr. Sara Imarisio, head of research at Alzheimer's Research UK, said, "This research adds to a growing body of evidence suggesting exercise as an important way we can look after our brain health. Although the people in the study self-reported their own level of exercise, which could make it less accurate, high levels of mid-life physical activity were linked with fewer signs of brain damage. The observation that those who exercised more had less damage to the small blood vessels that spread through the brain suggest that physical activity may impact brain health largely through effects on the blood supply.
"As the UK's leading dementia research charity, Alzheimer's Research UK is now funding work to see how feasible it is for people in midlife to take up exercise as part of a healthier lifestyle, with a view to larger trials that assess the effect on brain health.
"Just a third of people think it's possible to reduce their risk of developing dementia, compared to 77% who believe they can reduce their risk of heart disease. While there is no sure-fire risk way to prevent dementia, our brains don't operate in isolation from the rest of our bodies and a good rule of thumb for everyone is that what is good for your heart is also good for your brain.
"The best current evidence suggests that as well as staying physically and mentally active, eating a healthy balanced diet, not smoking, drinking only within the recommended limits and keeping weight, cholesterol and blood pressure in check are all good ways to support a healthy brain as we age."
A prospective analysis of leisure-time physical activity in mid-life and beyond and brain damage on MRI in older adults by Palta et al., is published in Neurology, the Journal of the American Academy of Neurology on 06/01/2020.