EXPLAINER: How figure skaters deliver quadruple jumps

BEIJING (AP) — Russia’s “Quad Squad” of figure skaters will try for an Olympics podium sweep by landing the thrilling quadruple jumps that remain rare in the women's competition. But could skaters one day add a fifth rotation to their jumps?

Sports experts say it’s not clear what the human limits might be on the number of rotations a skater could complete. Quadruple jumps have become standard in the men's competition since Canadian Kurt Browning landed the first one in 1988. For women, Japan’s Miki Ando achieved the feat in 2002.

Yet the quads on display in women’s skating at the Beijing Games only came onto the scene in a big way in the last few years.

Here's a look at how the jumps are achieved.

WHAT DETERMINES THE ROTATIONS IN A JUMP?

To get in as many rotations as possible during a jump, experts say skaters need to launch themselves as high and far into the air as possible to maximize their spinning time.

The speed and strength needed for launching — and landing — is partly why quads are more common in men’s skating.

But a factor that could favor women is a skater’s body dimensions. A skater with a narrow frame, for example, might have an advantage over those with wide shoulders, said Rajiv Ranganathan, an expert in body movements at Michigan State University. That could let them hold their bodies more tightly with their arms in the air, allowing them to achieve more rotations.

WHAT DO QUADS ENTAIL?

A quadruple jump entails four rotations, as the name implies. But exactly how skaters achieve the feat can vary.

In recent years, it’s become more common for skaters to start spinning before they launch off the ice, said Polina Edmunds, who competed in the 2014 Olympics in Sochi. That spin – known as pre-rotation – is...