"Vault of death": The move even Olympian Simone Biles wouldn't dare try

United States' Simone Biles performs on the balance beam during the artistic gymnastics women's individual all-around final at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Thursday, Aug. 11, 2016. (AP Photo/Dmitri Lovetsky)
Dmitri Lovetsky, AP

Nineteen-year-old Simone Biles won the gold medal in the women's individual all-around gymnastics. Biles also earned the highest score on the vault, reports CBS News' Jamie Yuccas.

From the start of the Rio Olympics, Biles, a 4-foot, 8-inch bundle of muscle, has been a step ahead of the competition.

"I think for Simone, whether she wins five gold medals or whatnot, I think what makes her so dominant is her difficulty," said seven-time Olympic medalist Shannon Miller.

But despite Biles' great skill, there's one move so difficult even she won't try it.

It's known as the "vault of death." Russian gymnast Yelena Produnova first landed it in 1999.

An Egyptian gymnast tried it in 2014 and narrowly avoided serious injury.

In Rio, two are expected to attempt it. Indian gymnast Dipa Karmakar is one of only five women to successfully land it.

Another is Oksana Chusovitina, a 41-year-old mom and two-time Olympic medalist from Uzbekistan competing in her seventh Olympics.

So what makes this vault so hard?

The gymnast sprints down the runway, does a front handspring and launches into two and a half somersaults forward before ideally landing on her feet. Even the best athletes say this ends one of two ways.

"It's one of those skills where either you're on or you're injured and it - there's no way," Miller said.

Kyla Ross was a member of the Fierce Five who won team gold in London.

"I think the biggest challenge is just gaining enough height off the table," Ross said.

And in vaulting, when even one detail is off, it can mean disaster. One French gymnast broke his leg last weekend in qualifying.

And in the 2000 Sydney Games, gymnasts sat, flopped and crashed, after the horse's height was set too low.

Sunday night's vault final is the first of four individual event finals for the female gymnasts. Simone Biles will compete in three of those, meaning by the end of next week, she could be winner of five gold medals.