A Kind Of Chaos: The Science And Sport Of Bobsledding

Imagine a minute of pure adrenaline: a race down a track of ice at speeds up to 90 miles an hour, enduring crushing gravitational forces around the curves.

Bobsled is one of the thrilling — and punishing — sports in the Winter Olympics. The U.S. hopes to repeat its recent medal-winning performances at the 2018 Olympics next February in Pyeongchang, South Korea.

Meantime, they're competing on the World Cup circuit, including a stop in Lake Placid, N.Y., site of the 1932 and 1980 winter Olympics. High up on Mt. Van Hoevenberg, bobsledders from around the world launch into practice runs. The glistening track is about a mile long, with 20 sharply-banked curves. It's beautiful, but terrifying.

"A good run, especially in Lake Placid, can feel like you've been shoved in a metal garbage can and kicked down a rocky hill," bobsled pilot Elana Meyers Taylor says.

She's a two-time Olympic medalist (silver in Sochi in 2014; bronze in Vancouver in 2010).

"Yeah, it can hurt," fellow driver Jamie Greubel Poser, who won bronze in Sochi, says. "We consider bobsled an impact sport. You're hitting walls at 80 miles an hour. It can literally feel like a boxing match. I've 'seen stars' driving."

"[When] we're going down, the whole thing is just vibrating," pilot Nick Cunningham says. "It's loud, it's cold, there's no padding inside the sled. It's very, very uncomfortable. But when you win a medal, it makes everything completely worth it."

A bobsled ('bobsleigh' via the Olympics website) run starts with the all-important push: the initial burst of acceleration, as athletes run alongside the sled, propelling it down the first 50 meters of the course. The sleds themselves weigh hundreds of pounds, so explosive strength and speed in the push are critical. (It's no accident that many bobsled athletes, Greubel Poser and Cunningham among them, come to the sport from the world of track and field).

After the push comes the load. In a two-person bobsled, the pilot jumps over the side into the front, while the brakeman vaults in from behind like a long jumper. They have to do it both quickly and delicately, so the sled doesn't skid out. (Watch a video explainer here).

In the four-man event, the choreography is even more intricate. The team must cram four massively muscular bodies into a narrow bobsled while sprinting at full speed. They need to perfectly coordinate who jumps in first, in what order they sit down, and where their legs go as they fold themselves in.

"It's kinda chaos sometimes," says Evan Weinstock, who sits in the second position, just behind the driver. Only the driver has an actual seat; the others sit on their heels, "tucked up in a little cannonball position," Weinstock explains.

"It's tough," he says. "You definitely get a lot more flexible. If you weren't before you got in the sport, you are now."

Another peril is that bobsledders wear shoes studded with sharp spikes for traction on the ice. Bad things can happen when they jump in the sled and have to jam their feet under the teammate in front of them.

"We're only wearing little layers of spandex," Weinstock says."So sometimes you get a spike in your thigh or your calf. It's just part of it."

Once they load, the athletes hunker down low to be as aerodynamic as possible. Bobsled races are won or lost by hundredths of a second, so every tiny amount of drag or friction can spell trouble.

"Any single steer you do slows the sled down because it creates friction," Elana Meyers Taylor says. "Who can slow the sled down the least wins the race."

During the descent, it's all in the hands of the pilot, who steers with two "D rings" attached to cables that turn the front axle.

"You're pulling right to go right, and you're pulling left to go left," Cunningham says. "I look like I'm playing a little video game."

The others in the bobsled keep their heads down, so they don't actually see anything as they hurtle down the course. Pilot Nick Cunningham says that's probably just as well.

"I don't want them to realize some of the things I've seen in the front of that sled," he laughs. "There's been some hairy times goin' down where I'm, like, 'that was dangerous!'"

But even so, he won't admit it to his teammates: "I'm just, 'All right, guys, that was a good trip! Let's go back to the top.' And I'm sitting, going, 'Oh man, that wasn't good at all!'"

As the sleds speed around a curve, essentially vertical on a wall of ice, spectators can see the athletes' bodies shaking from the intense pressures exerted on them. Bobsledders endure forces up to 5 Gs, which means they'll feel force equal to five times their weight.

"It's like the G forces are trying to suck you through the bottom of the bobsled," Evan Weinstock says. "It forces our stomachs through our legs. It feels like you're getting folded in half like a pancake."

One tiny wrong move in a bobsled can mean disaster.

"Crashing is one of those things that it's not a matter of if, it's just a matter of when," Elana Meyers Taylor says.

She's crashed more times than she can count.

"There's sharp things in the sled that'll cut you up," she says. "And the biggest thing is, it is very, very loud. It is scraping, and it is piercing."

In the sport of bobsled, Meyers Taylor says, "we're all playing with Newton's laws. And whoever can navigate those laws the best, wins the race."

"A lot of physics actually goes into it," Cunningham adds with a grin. "Go figure, because in high school, I was always, 'Ah, I don't need this stuff, I'll never use this stuff again.' And now, that's how I make a living."

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