Practice doesn’t always make perfect – that’s why you’re not in the Olympics | Martha Gill

Don't put your faith in the 10,000-hour rule - some athletes are born with talents the rest of us will never have

Stefan Holm was told he was too short to be a high jumper. But by the time he won Sweden a gold medal in the 2004 Olympics, he had honed himself into the perfect projectile. It was the result of a 15-year obsession: his whole life had been pulled into alignment with this goal. If he wanted to stop on page 225 of a book, he would push himself to page 240, in order to train his mind to overshoot. It's all about your 10,000," he told David Epstein, author of The Sports Gene. There had been jumpers who had beaten him when he was young, and where were they now?

But in 2007, entering the world championships in Japan as the favourite, he faced an unknown opponent: Donald Thomas, from the Bahamas. Thomas had begun jumping just eight months previously, on a whim after a bet, and admitted he found the high jump kind of boring". He had slacked off training - his form was all over the place - and his coach couldn't even persuade him to wear the right kind of shoes. But he had one big advantage: an achilles tendon that could store just a bit more elastic energy than everyone else's. That year, Thomas sprang awkwardly over the bar to victory.