How Does Usain Bolt Run So Fast?

Usain Bolt was a superstar sprinter at the athletics World Championship in Beijing this week. He won the 100m and 200m. Since the 2008 Beijing Olympics, he has been a winner at every championship.

How did that happen? Does he swing his legs fast?

"Elite sprinters don't swing their legs any faster than recreational runners," says Dr Sam Allen of Loughborough University.

He just takes longer and more powerful strides.

In fact, research shows that while an amateur runner takes only 50 and 55 steps to complete 100m, the top sprinter would take 45.

"Elite athletes generate so much more power, owing to the fact they naturally have more fast-twitch muscle fibres. These elite athletes therefore spend a lot less time on the ground which results in them being propelled forward much quicker," says Allen.

Studies led by the American based researcher Peter Weyand show that at top speed, the crème sprinter's foot typically spends 0.08 seconds in contact with the ground at the beginning of each stride, compared with about 0.12 seconds for an amateur athlete.

As Sam Allen puts it, the sprinter is on air about 60% of the time, without any foot on the ground. For amateur athletes it's more like 50%.

However, Usain Bolt stands out due to his height, according to bbc.

"Bolt is a genetic freak because being 6ft 5ins tall means he shouldn't be able to accelerate at the speed he does given the length of his legs," says former Great Britain sprinter Craig Pickering.

"At the beginning of a race you want to take short steps in order to accelerate, but because he's so tall he can't do that. But then when he reaches top speed he has a massive advantage over everyone else because he's taking far fewer steps."

Hence, Bolt finishes a 100m race in just 41 steps, which are three or four steps less than his rivals.

"Stride length is the biggest determent between a good sprinter who's able to run under 10 seconds [in the 100m] and those sprinters who can't," Pickering says.

Even though training and coaching is important, Sam Allen says that "the best sprinters will always benefit from having a huge amount of natural ability".