![]() ![]() As her feet come closer to the ground, her arm comes back to her trunk. Her proprioceptive sense of her body’s position in space is so unerring that Biles can make attitude adjustments like she has retro rockets. Here, at least, Biles is piloting her descent. “She moves her arm backward, and that helps her align her trunk and her legs so she can finish her turn.” It’s called a secondary-axis turn, a movement of part of the body outside the direction of angular momentum that siphons some of that motion off into a different direction. “She extends her right arm in a small circle,” Sands says. But she’s high enough to be able to do something about it. She’s facing the mat, and, as far as Sands can tell, Biles realizes that she’s a tiny bit under-twisted. Near the end of her second somersault, Biles opens her tuck a little. Freeze-framing through Biles’ routine, Sands points to one small midair adjustment that shows how skillful her landing was. Her arc and rotation-longitudinal and transverse-aren’t completely ballistic, though. By shifting her angle slightly, Biles primes her body for twists and flips in the air-and because she’s moving so fast, and bouncing so high, she has time for lots of both. That’s why Biles starts her flight with arms wide, then brings them in while straightening out her body. It also helps that Biles is relatively small and tremendously strong smaller people flip faster when they tuck because, in physics terms, they have a smaller moment of inertia. Give one a twist in one direction and the whole assembly will flop around. Pretend, as the physicist Cliff Frohlich proposed, that a body is basically just two cylinders joined at the ends, like unattached sausage links. A so-called cat-twist rotates one part of the body in the opposite direction of another. Twisting in the air’s possible, yes, but it takes a different set of skills. “She does the twist from the supporting surface so she doesn’t need to rely on twisting in the air,” Sands says. This is Biles initiating her twists and somersaults before she ever leaves the ground. ![]() In the floor routine she starts in a “puck” position-part pike, a bend at the hips, and part tuck, in which both hips and knees bend-and twists about an eighth of the way around. On the floor as on the beam, she then makes another subtle adjustment. It’s because as she arcs and tumbles through the sky we see the literal heights a human can achieve-a body and mind, through action and movement, perfected. Videos of Biles’ performance have dominated media since her performance not only because she won, or because her moves are precedent-setting. (The “two” is because Biles already has a move named after her, one of the rare occasions when a sequel is as good as the original). ![]() After that, it’ll be called the Biles II, because she’s the first woman gymnast to nail it. It’s called a triple double, until Biles does it again in international competition-and there’s no reason to think she won’t. And then, pow pow, Biles is in the air, a möbius loop of motion 10 feet off the ground at the apex, more than a second in the air, twisting around her head-to-toe axis three times and flipping over her side-to-side axis twice before, bang! Her legs hit the mat again. Without losing much velocity, she pivots 180 degrees (a sort of y-axis cartwheel called a roundoff) and goes into a handspring. By now you’ve seen the video-at the beginning of her floor routine at the US Gymnastics Championships last weekend, Simone Biles barrels across the mat at ludicrous speed.
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