Many individuals look forward to living to a ripe old age, with the caveat being that they remain in a decent state of health. Ideally, our later years should be vibrant, and not too tinged with signs of physical or mental decay. There are several lifestyle factors that can help ensure healthy ageing, including diet, sleep and sunlight exposure. Another one, of course, is exercise.
Traditionally, exercise has been touted for its benefits for physical health. Regular has been associated with a reduced risk of a variety of conditions including cardiovascular diseases and type 2 diabetes. But health is not just about the body: it’s about the brain too. What, if any, influence does exercise have on brain function?
Well, there is ‘epidemiological’ research which links higher levels of activity with better brain function. The problem with this research (like pretty much all epidemiological research) is that it only tells us that activity and improved brain function are associated. It might not be the case that activity actually boosts or helps preserve brain function. Maybe those who are active eat better and smoke less, and its these factors (not the activity) that have benefits for the brain.
To establish whether exercise does indeed benefit the brain what we really require is ‘intervention’ studies. Studies where individuals are put through some sort of exercise programme while their brain function is assessed.
Such a study was published recently in the journal Frontiers in Aging Neuroscience [1]. In this study, a group of sedentary individuals aged 59 – 80 had their brain function assessed. They were then randomised to one of two exercises regimes:
- walking (at one’s own pace) for 40 minutes, three times a week
- regular stretching and toning exercises
Study subjects were reassessed after 6 and 12 months.
Assessment took more than one form. One test employed was ‘functional magnetic resonance imaging’ (fMRI). This tests brain activity. One part of the brain the researchers were particularly interested in is known as the ‘default mode network’. This part of the brain in most active when individuals are inwardly focused, but becomes naturally more quiet once someone has to focus on their external environment for some reason.
Previous research has shown that fitter individuals have greater ‘connectivity’ in their default mode network, and also tend to be better at a range of mental tasks including planning, prioritising and strategising. This work is epidemiological though, so let’s get back to the intervention study that is our focus here.
At the end of the study (12 months), compared to those who had been stretching and toning, those on the walking regime saw, on average, an increase in the default mode network connectivity. They also saw increased activity in another part of the brain (known as the ‘fronto-executive network’) which assists individuals perform complex tasks.
Crucially, though, the walkers did on a range of cognitive tests too, especially those that are sometimes referred to as ‘executive control tasks’ (e.g. planning, scheduling, dealing with ambiguity and multi-tasking). It is these skills, by the way, that do tend to take a bit of a hit when we age.
What we have here is an intervention study showing that activity in the form of walking, even in later life, has the ability to help enhance brain function, especially in terms of functions that are prone to decay as we age.
For more information on why walking may be the ideal exercise while we age, see here.
References:
1. Voss MW, et al. Plasticity of brain networks in a randomized intervention trial of exercise training in older adults. Frontier in Aging Neuroscience doi: 10.3389/fnagi.2010.00032
