Pole vault: Inside the vault

Jin Minsub of South Korea competes during the Men's Pole Vault final at the 2014 Asian Games. Photo / Getty Images

It's easy to be dazzled by the artistry of the pole vault as athletes propel themselves to improbable heights, hang in space for a pregnant moment as they cross the bar, and fall grace-fully to padded ground.

But as elegant as the spectacle is, what makes it work is a matter of hard science.

The essence of pole vaulting lies in the confluence of different forms of energy. A pole vaulter stands at the top of their run-up with reserves of chemical potential energy they have gained through eating.

But as they begin their sprint towards the bar, carbon fibre pole in hand, their motion is defined by kinetic energy. As the pole is speared into the box at the bottom of the bar and they are launched into the air, their kinetic energy is absorbed by the pole and gradually converted into gravitational potential energy.

The higher the athlete sails, the less kinetic energy they use, which explains the hanging effect in the air at the moment pole vaulters try to clear the bar.

At the top of the vaulting arc, the idea is to use just enough kinetic energy to cross the bar.
The keys to success in pole vaulting are a fast run-up and optimal transitions through the different forms of energy in play.

Because of this, strength is not a core requirement of the job. Rather, height, speed and flexibility are the most important physical attributes.

"Pole vaulting is almost strictly a matter of energy," Canadian scientist Peter Watson told ABC News. "So the [height] limit is designated by how fast you can run carrying the pole."

But while speed is crucial, technique also plays an important role if an athlete is to properly harness all the available energy. As American scientist Peter McGinnis points out, not all fast sprinters can vault.

At each stage of the process, from the sprint to the planting of the pole to the timing of the leap, critical energy can be lost. McGinnis says the athlete should jump off the ball of their foot at the precise moment the pole connects with the landing box.

Pole vaulting is said to have started in Europe where gentlemen amateurs would use a pole to help them leap across canals. The current version of the sport emerged towards the end of the 19th century, when competitors used bamboo poles to clear a bar.

In the first Olympic Games of the modern era, held in Athens in 1896, William Hoyt of the United States won gold with a vault of 3.30m.

Current records show how far the sport has come. Ukraine's Sergey Bubka holds the world outdoor record of 6.14m, set in 1994, and Frenchman Renaud Lavillenie extended Bubka's 21-year-old indoor world record by 1cm when he cleared 6.16m last February.