Many Winter Olympic sports activities have ancient origins, courting to instances when people invented new methods of getting round within the harsh, white wilderness. Snowboarding could have first emerged 10,000 years in the past in Altay, China, and the Indigenous Sámi phrase for snowboarding (“čuoigat”) is estimated to be 6,000 to eight,000 years previous. 1000’s of years in the past in Northern Europe, folks strapped animal bones to their ft to skate round on ice. And the First Peoples in Canada used toboggans to move items.
The game known as skeleton has no such hallowed origins within the sensible transport of people or items, regardless of technically happening on a sled. Life was exhausting sufficient with out central heating; there was no purpose to hurdle face-first down a frozen chute on a brakeless sled.
But for all of the modernity of skeleton — it was reintroduced to the Winter Olympics lineup solely in 2002 — scientists are nonetheless deeply puzzled by it.
The opposite sliding sports activities present clearer paths to victory. Bobsled drivers steer by pulling on two items of rope hooked up to a steering bolt. Lugers steer by flexing their calf muscle groups and gripping the sled’s handles. However skeleton racers can information themselves with solely the subtlest of shoulder shrugs or foot faucets. The slightest twitch might help or damage by altering the athlete’s aerodynamics in ways in which athletes, coaches and researchers are nonetheless attempting to decode.
“There are even instances after I simply use my eyes,” Katie Tannenbaum, a skeleton athlete from the Virgin Islands, told The Times in 2018.
Skeleton was invented on a little bit of a whim, based on the Worldwide Bobsleigh & Skeleton Federation. The game began within the late nineteenth century on the Cresta Run, an icy out of doors observe used for sledding in St. Moritz, Switzerland, when leisure sledders started careening down headfirst. And though the title “skeleton” matches a sport that would appear to ask demise head-on, it has murky origins; it could have arisen from a poorly Anglicized Norwegian phrase or the metal sled’s sparse, skeletal look. The game appeared within the Olympics in 1928 and 1948, when the video games have been held in St. Moritz.
The physics of the sliding sports activities — skeleton, bobsled and luge — are easy. “It’s gravity that pulls you down the observe,” mentioned Timothy Wei, a mechanical engineer with experience in fluid dynamics at Northwestern College, who works with skeleton athletes. “And all of the drag forces are slowing you down.”
Discover the Video games
A lot of the sparse, nonproprietary analysis on skeleton considerations the sprinting part of the game, the place athletes run to generate velocity whereas pushing their sled throughout a brief distance earlier than leaping aboard. Scientists have investigated the ideal number of steps, the ideal step length and frequency and even the ideal angles of the hips, knees, ankles and thighs in the course of the operating part. However scientists know far much less in regards to the mechanics of the extra terrifying part of skeleton.
There are numerous causes.
The sliding is physically brutal: Athletes endure 4 to 5 G-forces of stress round turns and should face up to the rattling vibrations of the observe. In luge, athletes put on a neck strap to carry up their head beneath excessive G-forces; bobsled athletes, seated, are enveloped by their automobile. In skeleton, athletes expertise the weather face-first, all whereas tucking their heads down to stay streamlined, chins hovering simply inches above the exhausting ice and eyes straining upward to visualise the observe.
“You’ll be able to’t do greater than two to a few runs per day,” Dr. Wei mentioned. “And by the tip of the season, for one or two months you simply can’t assume clearly.” So whereas a runner can observe operating every time they like, a skeleton athlete is ready to skeleton for just a few cumulative hours per 12 months, if that; with few alternatives for testing, skeleton runs are logistically tough to review.
It’s not straightforward to get to a observe for observe. The Worldwide Bobsleigh & Skeleton Federation lists simply 17 tracks world wide, all situated within the Northern Hemisphere. This exclusivity creates economic and environmental barriers for sliders from different international locations hoping to coach, not to mention make it to the Olympics.
And the tracks are sometimes serpentine, winding like curler coasters, making it tough to maintain a steady eye on an athlete as they barrel down the observe. The observe on the Yanqing Nationwide Sliding Heart in Beijing, additionally known as “the Snow Dragon,” has a 360-degree flip. From Dr. Wei’s expertise, watching a race means “you simply watch these guys dash and disappear right into a tunnel and so they’re gone.” He added, “There’s no technique to know precisely what the athlete is doing alongside your entire observe, and to get information off it.”
However in a race the place victory margins are usually a number of hundredths of a second, it’s essential for athletes to grasp the aerodynamic forces slowing their slide, so as to reduce them. Along with your face pointing towards the ice, it may be exhausting to know whether or not tweaking the place of your foot or sliding up or down on the sled truly shaves off treasured time.
Enter the common-or-garden wind tunnel. Greater than a decade in the past, Dr. Wei constructed a system that simulated the drag resistance that athletes expertise in an precise skeleton run. He constructed a mock part of a observe on the exit of an open wind tunnel with sensors embedded within the ground, close to which he mounted a mock sled. The sensors tracked the drag forces and weight distribution of the athletes.
Athletes mounted a mock sled, braced themselves in opposition to the gusts of wind, and have been in a position to view in real-time how slight changes of their physique affected their velocity by a plexiglass window on the ground of the tunnel.
Dr. Wei additionally carried out checks utilizing a theatrical fog machine and illuminated by a inexperienced sheet of laser mild. He tracked the motion of the fog particles to disclose how air swirled over the athletes’ our bodies and heads, within the hopes of gaining perception into additional methods of decreasing drag.
Ms. Tannenbaum, who is about to compete for the Virgin Islands this week, labored with Dr. Wei’s wind tunnel to organize for Beijing. (There aren’t any bobsled tracks within the U.S. Virgin Islands.) “The place is the drag coming from?” Dr. Wei questioned. “How a lot of it’s from the sled itself, and the way a lot is from Katie?”
A wind tunnel can not replicate the surprises of an actual observe, the place sure components — the tiny bumps on the ice, the wind circumstances, the out of doors temperature — will at all times be out of the athlete’s management.
A part of the great thing about skeleton, in contrast with the opposite sliding sports activities, could also be that it asks athletes to relinquish complete management over their future on the ice.
“Regardless that it appears to be like fully insane, in some ways it’s the most secure of the sliding sports activities paradoxically as a result of you’ve got so little steering management,” Dr. Wei mentioned. Oversteering in these sports activities can usually result in a crash. Luge, the place speeds can high 90 miles per hour, is taken into account probably the most harmful sports activities within the Olympic Video games.
Probably the most aerodynamic skeleton racer wouldn’t be a fleshy human, however an precise skeleton — the wind would whistle proper by the rib-cage, Dr. Wei mentioned, including that an precise skeleton wouldn’t have the ability to steer.
Till the Olympics opens to the undead, the game of skeleton stays within the area of the dwelling. And although the athletes could look as nonetheless as corpses, there may be nothing extra resolutely alive than clinging to a metal plank, sliding 80 miles per hour towards the middle of the Earth, over and over and over.
https://www.nytimes.com/2022/02/10/science/olympics-skeleton-physics.html The Slippery Science of Skeleton