Treadmills are boring. Kick-boxing hurts. Press-ups make your arms tired, and getting up early to swim lengths sucks.
No wonder gym memberships lapse and expensive running shoes end up in bottom drawers: the far-off promise of a six-pack and a healthy heart just can't compete with the immediate allure of indolence and inertia.
But according to Australian philosopher Damon Young, the problem isn't exactly laziness, and the solution isn't simply to try harder.
The real reason we abandon well-intended exercise regimes is that we're thinking too much like Descartes - and the way to fix it is to get a bit more Socratic. A rudimentary grasp of the writings of Heidegger, Aristotle, Camus, Hume and Tolkien may also help.
This is, of course, a bit daft, but in his thoroughly readable treatise How to Think About Exercise, Young skips through a couple of millennia of philosophical writings on the subject of exercise, extracts the most useful bits and then, in a style reminiscent of self-help-through-high-culture guru Alain de Botton, explains how you might use all this erudition to improve your life.
Young, whose other works include a study of the gardens of famous thinkers, a pop-philosophy history called Distraction and a children's book called My Nanna is a Ninja, will this week appear at the Christchurch Writers and Readers Festival.
Earlier this month, on the phone from his home in Melbourne, he explained why the world needs a book about the philosophy of exercise. The book, says Young, is "a morale boost" for bookish folk who are interested in exercising more but find themselves alienated by a fitness industry "which can be anti-intellectual at times".
Conversely, there are sporty folk "who might want to think about it a bit differently". And then there are the people who'll drag themselves along to the gym in the hope of becoming healthy and beautiful, then give up after six months.
"I'm suggesting that's because they're focussing on the wrong part of exercise," says Young. Rather than treating your body like a car that needs to be taken to the mechanic for a tune up, why not "pay attention to what it does for your character, your intelligence or imagination"? Those benefits will keep you absorbed for a lifetime.
So what has Descartes got to do with all this?
Young isn't exactly blaming your double-chin and pot belly on the 17th-century French philosopher, but Descartes was the first to convincingly articulate for the concept of dualism: the idea that the body and the mind are separate, that the real you is your mind, and your body is just an unreliable, short-lived vessel.
You don't need to read Descartes to believe this, says Young. It's quite reasonable to feel "like we are minds stuck in bodies that are flawed - they feel pain, they get sluggish, they can be a source of wayward impulses".
But Descartes was wrong. Body and mind are inextricably linked; we are "inescapably fleshy". The philosophies you should be listening to, says Young, are those such as Socrates', who reckoned "people's minds are so invaded by forgetfulness, despondency, irritability and insanity because of their poor physical condition that their knowledge is actually driven out of them".
Or Aristotle, who reckoned we are a bundle of dispositions which can be strengthened with training. Young was his own guinea-pig for the book. He tried yoga to see if it would awaken a greater awareness of his own physicality (it did, but he later quit). He boxed, swam and ran in search of the salutary values of pain, fear and boredom respectively.
Young convincingly argues that brain and brawn should co-exist in one body. But there's more: self-help tips. "One of the themes of the book is that you should try something that complements your personality rather than matches it," says Young.
"So someone who is overly humble and is down on themselves - they may want to try exercise that will enhance their pride, such as sprinting up a hill as fast as they can.
"Someone who is full of themselves - thuggish, braggardly - may want to take something humbling like rockclimbing, where having massive upper-body strength might be handy but what you really need is caution and skill and patience.
"If there are gaps in your character you can use exercise, in some cases, to fill them up." It's not like taking a pill, says Young. It won't work for everyone all the time. "But there's good evidence it will work for some people."
There's one more reason Young likes to exercise: "I'm going to die one day. I'll no longer be a body. I might as well see what it can do."
How to Think About Exercise, by Damon Young Macmillan
For details of Damon Young's appearances at the WORD Christchurch Writers and Readers Festival, see www.wordchristchurch.co.nz
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