I have a vision of a visitor arriving in Toronto this autumn from a distant war-torn country. As his host drives him into town, their trip is temporarily interruped by a marathon race; they must stop to let the runners pass. The perplexed visitor turns to his host and asks, "What are they running away from?"

I am one of those marathon runners and I have been asked similar questions. Why do I do it? What am I fleeing? The curiosity and cynicism is logical; we runners have been described as compulsive personality types, weight-obsessed and prone to alcoholism. The average marathon field might well contain a fair number of unbalanced, anorexic drunks trying to outdistance their own neuroses.

I am not an elite athlete; I neither win nor lose the race. I run in the back half of the pack, with aging executives and heavy-hipped women in long white T-shirts. The folks running near me are there to go the distance, but they are challenging themselves only. There is conversation and laughter. As we reach the halfway point, people are making plans for brunch afterwards. Later, we fall silent as our muscles stiffen and our feet begin to hurt.

A marathon is 42.2 kilometres long. Some of these kilometres can be uncomfortable. To actually want to run such a distance can be puzzling to those whose hobbies are less exacting. There is no immediate gratification in pounding each one of your feet into the street pavement 21 000 times over a period of four hours. Neither is a lot of sensual pleasure stimulated by clomping along the road mile after mile as your legs turn to painful stumps, your dehydrated bloodstream acquires the viscosity of tomato paste and your body becomes caked with a layer of sweaty salt.

Some of my friends wonder why I spend so much time and energy on a pursuit that causes such apparent anguish among its practitioners - more so than, say, shopping for antiques on a sunny Sunday afternoon. Why do I run?

Is it because I want to feel superior to my sedentary friends in the same way that the aviator feels superior to earthbound mortals? Maybe I acquire self-satisfaction in listening patiently to someone tell me of the new vibrating Barca Lounger they've just had delivered while I am cooling down my tingling quadricep muscles after a 20k training run. Is it smugness I seek?

Am I fleeing our pervasive modern technology by attempting to rediscover something primordial, more basic, something that people have been doing naturally since our species first walked upright? There could be something in this, although the theory is discredited somewhat by the computerized timing chip strapped to my ankle as I run through the urban jungle.

Am I looking for the kind of challenge that is disappearing from my everyday existence? Not many of us go off to war these days. We do not have to cope with bubonic plague, cataclysmic natural disasters or marauding bands of sabre-toothed tigers. Let's face it, we are part of a society that was transfixed by the televised story of 16 dysfunctional castaways all trying to claw and backstab their way to a million-dollar prize. Are some of us looking to endurance sports as a way to become real survivors in our own lives?

Some years ago a running shoe company ran an ad that suggested we runners were actually fleeing old age itself - as if that were possible - and that we would succeed if we bought their product and just did it. Did this sell any shoes? I hope not.

Popular lore holds that we run for the fitness, weight control, or to find inner peace in an age of anxiety. The fact is that all of these things are a by-product of running, not a goal. No weight loss agenda will carry you through a three-hour run in the blistering heat. People speak of a "runner's high." These people are mostly non-runners. I have never been high while running a marathon; sore yes, high no.

But if you were a runner you would know this:

At one point in a long-distance race, you will come to a place where all conversation ceases, and there is only the sound of rubber soles hitting the pavement and of runners breathing evenly. The other people around you are deep in their own thoughts, alone with their discomfort or despair, with their dreams or determination. This is a time of transcendental solitude, when no external source - no self-help book, no external coaching, no high-tech shoes - can get you to the finish line. You are locked away in negotation with your abilities and your limitations. It is an elemental moment that is redefined each time your protesting feet hit the ground.

About three-quarters of the way through a marathon, the fuel in your muscles is exhausted and you are literally running on empty. No one is quite sure what powers you through the last 10K, but this much is known: you are given an opportunity to reach deep into yourself to achieve personal greatness. By accepting this opportunity, you become extraordinary. In the end, it's not your legs that carry you across the finish line. It is your heart and soul.

In answer to our foreign visitor's question: we marathoners are running away, but not from old age or chubby thighs or the stresses of the world.
We are running from the shadow of the ordinary man, from the purgatory of spiritual indifference, and ultimately we are running out of mere being and into our essence.

We run in order to demand something supernal of our bodies and our souls, and to feel them respond.