Exercise and the Ageing Brain

A bit of a dry title for an article, isn't it? The only good thing to say about it is that if your brain can be described as ageing it means it's still alive - therefore so are you! So make the most of it! And that's what the Silver Grey Sports Club stands for - ageing doesn't inevitably equal decrepitude, it can mean being strong and fit and so having more time to do your sport. And here is yet more evidence that doing sport and exercise is not only fun and good for you physiologically, it's also good for your brain! It's not the first time we've written about this, and no doubt it won't be the last.


In fact there's such an avalanche of positive news about the effects of exercise on the brain that the May 2016 issue of the journal Neuroimage is almost entirely devoted to it! There are perhaps a dozen articles reporting on research studies showing how exercise benefits brain health and function - and many of those focus specifically on beneficial effects in older adults.


So, as they say, "Here's the science!".


In one of the studies, Claire Sexton and her colleagues from various parts of Oxford University demonstrated that higher levels of physical fitness and activity were associated with greater volume of white matter(WM) in the brains of older adults. Their results also demonstrated lower incidence of lesions and improved microstructure in the brain's white matter among people who exercised more compared with those who exercised less. In the summary of the report into their research, which involved reviewing the results of 29 studies of brain images of older men created using Magnetic Resonance Imaging Sexton and her colleagues found "evidence for cautious support of links between physical fitness or activity and White Matter structure". Even though it sounds a bit cautious, it's still an important conclusion, as the brain's white matter is something that has traditionally been lost during ageing. Another study, by Carl-Johan Boraxbekk and colleagues at Umea University in Stockholm, looked at the effects of long term exercise, over a period of ten years. They found better connectivity in an area called Posterior Default Mode Network, greater volume of grey matter in the Posterior Cingulate Cortex, and a higher perfusion rate - the rate at which blood is supplied - in the same area of the brain. All of these effects were associated with higher levels of physical fitness resulting from physical exercise.


In the opening of the summary to their report, Vivar, Peterson and van Praag from the National Institute of Aging, in Baltimore, USA wrote that that improved cognition had already been demonstrably associated with running. Their research showed that the reason for it was that running stimulated "increased neurogenesis" - the growth and development of nerve tissue - within a particular part of the hippocampus, an area of the brain associated with learning and memory. They described it as being as if "running re-wires the brain". A different study, by Michelle W Voss, of University of Iowa, Timothy B Weng of University of Illinois, and their colleagues, showed that "cardiorespiratory fitness has a positive relationship with functional connectivity of several cortical networks associated with age-related decline". In their research they showed that the important thing is the fitness level rather than the amount of physical activity undertaken.


Although the research generally does not establish the cause and effect relationship whereby these benefits occur, one study showed a relationship between physical fitness and greater blood flow to the brain, presumably due to a fitter, stronger heart's greater ability to pump blood more strongly. This seems like a fairly intuitive notion, that the brain, requiring a good blood supply and being the highest point above the heart, would suffer from an inadequate blood-flow, whether due to the effects of gravity or poor circulation, and would equally benefit from a better blood-flow produced when the heart is pumping more strongly more frequently. But as ever, having evidence from the scientific and medical research showing specifically how (and that!) this is happening is always encouraging, and especially when the participants in this study were aged between 59 and 69 years.


Other research studies looked into the relationship between physical activity and Alzheimers disease, a direct association between increased fitness level and increased volume and density of the hippocampus and so on.


The fact that one complete issue of this journal is given over to one area of research, and that so many articles on this subject are published at the same time, shows that the medical establishment is really seeing the enormous potential for successful ageing through exercise. Given that the world's population is ageing it's no bad thing, both for individuals and for society as a whole, since a healthier population of older adults will be less of a "drain" on social infrastructures and will, rather, be more of a net contributor.


So our message is - as ever - "Silver Greys, keep on doing what you're doing, it's good for you and it's good for everyone else, too!".