New research adds to evidence that exercise can improve cognition, especially later in life. The study found that older people who regularly exercised had greater levels of proteins crucial to their brain’s health, compared to those who didn’t exercise. These differences were apparent even in people whose brains otherwise showed possible signs of dementia, suggesting that exercise could slow down the progression of cognitive decline.
The study was conducted by scientists in the U.S., Canada, and Spain. They analysed data from an existing research project of older adults, the Memory and Ageing Project run out of Rush University in Illinois. As part of the project, volunteers undergo yearly medical tests, including a measurement of their physical activity. And upon death, they also agree to have their organs, including their brain, donated for further research.
The team looked at more than 400 volunteers in their 70s and 80s who had their physical activity measured over the years and had donated their brains for study. In addition to checking for signs of neurological disorders like Alzheimer’s disease, they examined the brain tissue for the presence of proteins important to synaptic function, which is needed for nerve cells to communicate with one another and with other cells.
Overall, they found that adults with greater levels of physical activity tended to have higher levels of these synaptic proteins. This association was seen even in people whose brains had markers of Alzheimer’s and other forms of dementia, like plaques and tangles. The study’s findings were published this month in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.
“The more physical activity, the higher the synaptic protein levels in brain tissue. This suggests that every movement counts when it comes to brain health,” study author Kaitlin Casaletto, an assistant professor of neurology in the Memory and Ageing Centre at the University of California San Francisco, told CNN.
This kind of research can only show an association between exercise and brain health, not demonstrate a true cause-and-effect. But other studies have suggested that regular exercise in mid to later life can possibly prevent or delay the symptoms of cognitive decline. The team’s findings, Casaletto said, might indicate that one way exercise helps is by keeping our synaptic function steady as we grow older.
The optimal amount of exercise is thought to be at least 150 minutes a week. But this and other research seems to find that any amount of physical activity can do the ageing brain good, so long as it can be done regularly.