There’s been a bit of a buzz recently about the benefits of exercise – and specifically walking – to our brains. It appears that exercise has both a direct effect, slowing the shrinkage of the brain (and even promoting neurogenesis) as well as an indirect effect by improving mood and sleep and reducing stress and anxiety. Problems in these areas frequently cause or contribute to cognitive impairment.
This is not a new story. Back in the 1990s scientists at the Salk institute for Biological Studies in California first discovered that exercise bulks up the brain. In ground-breaking experiments, they showed that mice given access to running wheels produced far more cells in the area of the brain controlling memory creation than animals that didn’t run. The exercised animals then performed better on memory tests than their sedentary lab mates.
Since then, scientists have continued the research and there are now many studies to show that the parts of the brain that control thinking and memory have greater volume in people who exercise than those who don’t.
One such study was conducted at the University of British Columbia in 2013. Researchers found that regular aerobic exercise, the kind (like Nordic walking) that gets your heart and your sweat glands pumping, appears to boost the size of the hippocampus. This is the brain area involved in verbal memory and learning. Resistance training, balance and muscle toning exercises did not have the same results. The results were published in the British Journal of Sports Medicine.
Other studies have shown that exercise improves what scientists call "executive function," This includes basic functions like working memory, planning and multi tasking as well as processing speed. Dr Alan Gow talks to Sian Williams about this and other brain benefits of exercise in the current Radio 4 series ‘How to have a better brain’. I was particularly struck by the statistic that one in three people over the age of 65 will develop dementia. You can catch the programme on iplayer.
The most recent study in this area (that I know about) is from the University of Kansas Medical Center, published last month. The researchers analysed the effect of regular exercise on levels of brain function in over 65 year olds. Their conclusion was that exercise improves visual-spatial processing (the ability to perceive where objects are in space and how far apart they are from each other) as well as overall attention levels and ability to focus.
Interestingly, in this study, it seemed that the intensity of the exercise mattered more than the duration. This means that improving our brain power relies on actually pushing ourselves, instead of just plodding along. I guess it gets the heart pumping faster, refreshing parts that normal activity can't reach (as a test of your memory - which larger advert does that part-plagiarise?).
In any event, it is an added reason to inject a bit of pace into your Nordic walking and get out of breath. It also follows on nicely from last week’s blog on the cardio benefits of Nordic walking. Another benefit to add to the list!