Simone Biles has been called the greatest gymnast of all time. But something went very wrong during one of her routines at the Olympics in Tokyo, Japan this summer. Biles sprinted down the mat and flipped into the air, hitting the vault table hands down. When she pushed off from it, she meant to rotate two-and-a-half times. Instead, she made only one-and-a-half rotations. And she landed awkwardly.
The problem was “a little bit of the twisties,” Biles later told reporters. She felt “a little bit lost in the air.” The twisties is how athletes describe a mental block that can mess with a sense of where their body is in space. “Suddenly, you’re not able to do this movement that you were able to do,” says Gregory Youdan. “You’re in the air, and you’re like, ‘I don’t know how to get down.’”

Youdan studies the science of movement and motor control at Dance/NYC in New York City. The group supports dancers in that region with research and advocacy. Problems similar to the twisties happen in other sports, Youdan notes. Golfers with the “yips” can’t follow through on swings, for example. And dancers can get disoriented. But the twisties can be especially dangerous, he says.
“Flying through the air is a much bigger risk to the athlete than losing your orientation during a dance turn.” No one can predict just who will get the twisties or when. Nor can they say how long it will take to recover. But scientists know a lot about parts of the brain that let athletes do complex skills and sense where their bodies are. So they have some ideas about what might trigger the twisties.

One factor that could trigger the twisties is a change in an athlete’s environment, Youdan says. In Biles’ case, because of the COVID-19 pandemic, gymnasts at the Olympics did not have an audience in the stands. So the sights and sounds were different from what athletes were used to at major competitions.
Stress may also play a role, Youdan says. In a video made after the Olympics, Biles said she had felt stressed even before Tokyo. “It kind of built up over time,” she said, “and my body and my mind just said no.”