He Used to Wear Trainers

"You have flat feet," said the man at the shoe shop. "Flat as a pancake." He had been analysing my stride, armed with a treadmill and a videocamera. News to me, but he had no reason to lie. He could have sold me any of a million shoes, but he picked out a pair that he said had the cushioning and support I'd need. I left the shop feeling I would forever continue to flog the ground miserably, now with officially flat feet.

A few weeks later The Economist took part in a corporate fun-run in Central Park. I did my usual, workmanlike stuff, 3.5 miles in half an hour. One colleague, Chris, finished in 24 minutes. He was wearing funny things on his feet: those shoes that look like gloves, with a finger for each toe.

I began searching online for "barefoot running". A friend lent me "Born to Run", a book from 2009 by Christopher McDougall, about a tribe of Indians in Mexico's mountains, nearly all of whom run vast distances for fun in thin, homemade sandals. McDougall had also found disparate researchers who disputed the shoe companies' mantra that cushioned is best.

I checked out the work of Daniel Lieberman, an evolutionary biologist at Harvard. His website had slow-mo movies of runners in different footwear with different footfalls. The key, I read, was not the shoes: it was the landing. Most Western runners, in thick trainers, extend their foot well in front of their body, and land on cushioned heels, taking long strides. But African children who own no shoes — like our ancestors—land on their forefoot, directly below the hip, and take shorter, lighter strides. The videos came with animated graphs: even in cushioned trainers, the heel-strikers experienced a sharp spike in the forces going through the leg. The unshod forefoot-strikers' arches flattened slightly, and the forces showed a smooth peak and fall-off. This is how we were born to run.

Studying the Harvard cross-country team, Lieberman found that forefoot-strikers had significantly less repetitive-strain injury. He advocates starting barefoot—literally. On a hard surface, not sand. Yes, on concrete even: it's no harder than the baked African savannah we evolved on. This, he says, forces the best form. You cannot land on your heel; it will hurt.

I did a few barefoot laps around the block. My feet felt wonderful. My steps were so light they almost felt mincing, which made me a little self-conscious. But I wanted to keep going, and going. Which, the barefoot gurus had warned, you should not do. Many converts love it so much that they injure themselves. Even if we were born to run this way, we haven't done so since our parents forced us into shoes, changing our walking as well as our running form. The muscles in the foot and lower leg had barely been used since then. Sure enough, the next day it felt as if I'd done hundreds of calf-raises with weights in the gym. Yet I couldn't wait to run again. I bought some flexible, cushion-free, slipper-like minimal shoes.

I added distance, starting with a quarter-mile, and adding 10% each run. I got faster and tweaked my form with the help of online coaches and videos. The soreness in my calves took weeks to fade, and as it did, the featureless cylinders that had been my lower legs began to sport something resembling muscles. One day, intending to run 3.5 miles (which used to wear me out), I got lost and ran five, loving every step. I asked my doctor: were my feet really flat? "Not at all." My graceless thumping of the treadmill had misled the shoe salesman. Now, my conversion was complete.

After a few months, I ran eight miles in the NYC Barefoot run, a non-race around Governor's Island with no winners, no clock and no set distance. All the barefoot gurus were there: McDougall, in thin leather sandals, ready with a high five. Lieberman, who likes to run around Harvard, was there, truly barefoot. So was Lee Saxby, a British trainer whose online videos have got many barefoot-runners started, wearing stylish minimal shoes by Vivobarefoot.

Many of those I talked to had once hated running. Many felt that city life kept us from living the way our bodies were meant to live. (The run's organiser, John Durant, is known as The Caveman for his meat-heavy "paleo" diet.) Several had stopped listening to music while running, so as to pay more attention to their bodies and their surroundings. Most had rejected GPS trackers and stopwatches. Rather than sweaty, pounding exercise against a timer, they tended to see running as more like meditation on the move.

After a personal high—a solo half-marathon—my form deteriorated as the cold forced me into shoes. Come the spring, I took them off again, and ran barefoot through my neighbourhood. It was glorious: light as could be, just like when I started. I ignored my feet and came home to massive blisters. In the past I'd gone five Brooklyn miles with no shoes, but my calluses had disappeared over the winter. The next day, hobbling, I couldn't wait for the blisters to go away. Not because they hurt, but because I was longing to run again.