(Photo by MARTIN BUREAU/AFP via Getty Images)

In her one, and perhaps only finals performance of these Olympic Games, Simone Biles launched herself into a vault that would require two-and-a-half twists of her body. Something went terribly wrong.

“I was trying a two-and-a-half,” Biles said, “and I ended up doing a one-and-a-half. Just got a little bit lost in the air.”

Former competitive gymnast Catherine Burns watched and winced.

“I know that feeling so deeply in my body,” Burns said, “of being, like, I’m lost, I came out [of the move] too early, where am I? And all of that is happening in the course of split seconds, that recognition of something’s not right and I need to be able to complete the trick without injuring myself.”

It’s called the twisties and it’s when gymnasts are in mid-air and lose awareness of where they are in the skill, making it difficult to land safely.

“You can get it on twisting moves,” Burns said, “but you can also get it on any kind of rotational move. [And] you can get lost in the air on a really simple trick that you’ve done a thousand times before.”

She went on to explain that gymnasts do so much work to be able to gain muscle memory and awareness of knowing where their body is in the air.

“Having that spatial recognition, being able to see yourself doing the trick, it becomes a point where it’s like built into your body,” Burns said, “and you do it sort of without thinking about it cognitively. And then sometimes you get these twisties [and] it’s sort of like a mental block that some people refer to as if you’re starting to cognitively think about [it] again.”

Biles’ former teammate, retired gymnast Aly Raisman, theorized that it may have been a case of the “twisties” when Biles left the competition.

“If she did get lost in the air, I do want to say that that is actually very common, because she’s doing such difficult skills and she can twist so much more than the average person,” Raisman told TODAY on Tuesday. “She’s human. Sometimes it happens, when you’re in the air, and we just kind of get confused.”

The “twisties” are considered the gymnastics version of the “yips,” when athletes struggle to perform skills that had usually come easily with muscle memory. The difference is that in gymnastics, a miscalculation in mid-air could mean a potentially catastrophic injury.

Biles also withdrew from Thursday’s all-around competition and is taking it “day by day” to determine whether she will compete in next week’s individual events.

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