Use it or lose it: The new science of keeping your mind and body healthy
Evidence is growing that regular exercise improves not just physical health but brain function and mental wellbeing. And we don’t have to become gym bunnies to benefit. By Ruth Nichol.
Unlike our closest relatives among the great apes, we can’t get away with spending our days lazing about doing nothing more strenuous than plucking the occasional piece of fruit from a tree.
We may share 99% of our DNA with them, but animals such as gorillas and chimpanzees can spend up to 20 hours a day resting, eating, grooming and sleeping without getting fat or suffering any of the health problems that plague modern humans, such as heart disease and diabetes.
Nor do they experience much in the way of anxiety or depression – at least when they’re living in the wild.
As much as we would like to loll about in a similar fashion – and we have used our superior brains to engineer our lives so that most adults now spend 70% of their time either sitting or lying down – we’re paying the price in terms of poor physical health and an epidemic of mental illness.
“We’re now at a point where we can order food, we can date, we can entertain ourselves without having to move a muscle – we don’t even have to get up to change the channel on the television any more,” says British science writer Caroline Williams.
In her recent book, Move! The new science of body over mind, she says our increasingly sedentary lifestyle means that as well as declining physical and mental health, we’re also weaker than we used to be. An American study of students aged 20-35 published in 2016 found that men’s grip strength had fallen over three decades, with Millennial males able to exert just 44.5kg of force compared with the 53kg their fathers could exert in the same test in 1985.
That in itself is likely to be a contributing factor to growing levels of mental ill health.
“The link between physical strength and anxiety and depression is just so strong,” says Williams. “That research has been around since the 1980s and you really can’t argue with it.”
IQ reversal
We seem to be getting more stupid, too. Recent studies have found that after decades of rising IQs (known as the Flynn Effect, after the University of Otago professor the late Jim Flynn, who first observed the phenomenon in the 1980s), IQs among young people are starting to fall – what’s known as the Reverse Flynn Effect.