Science Of Speed
Ice rocks!" wrote one exuberant speed skater in the official logbook. "Ice is the dope s--t!" raved another. These were not the words of desperate drinkers euphoric about getting a decent Long Island iced tea in Salt Lake City. The kudos in the log came from athletes singing the praises of the "fast ice" at the new $30 million Olympic Oval. To make it, icemeister Marc Norman (his actual title is operations manager) rigged up the Zamboni to spray deionized, purified water (impurities in ice cause friction with blades). He waited for each layer to freeze before unleashing the next flood, until he had some 24 layers totaling three quarters of an inch thick. The ultrathin layers make the surface as flat as the laws of Euclid allow, which already gets you pretty fast ice. But thin layers also freeze so quickly that almost no oxygen gets sucked in. Less oxygen makes ice thermally nimble: it melts and freezes quickly as the temperature changes. And at the Oval, the mercury taking the ice's temperature will rise and fall more than a mogul skier. Norman and his crew will soften up the ice a little for the 500-meter sprints, since a speedster taking a sharp turn at a 50-degree angle and 40 miles per hour likes to feel his blade grip into something. They'll freeze the rink harder for the men's 5,000- and women's 3,000-meter events, since distance skaters need glide, getting as much forward momentum out of each push. As a result, all 10 world speed-skating records could fall during these Games, something that's never happened in a modern Olympics. On the first day of competition, Jochem Uytdehaage of the Netherlands broke the world record in the 5,000 meters by 4.06 seconds.
When the words "performance enhancing" and "Olympics" occur in the same sentence, you can usually find the word "drugs" nearby. But at this Olympics, performance enhancements have gone legit. Besides fast ice, there is fast snow: at both the downhill and the super G courses at Snowbasin, site managers deployed Sno-Cat machines to pack the snow and sweep the fluffy stuff away, and may water down the course to give it an icy topcoat. Some tricks are harder to spot. From indium-coated snowboards and hourglass-shaped skis, science is promising to coax stellar performances from the Olympians. Because every ski, bobsled, luge and skeleton course is different, there are no world or Olympic records in those events. But there should be course records aplenty. And if it seems odd that athletes are seeking the winning edge outside their own bodies, there's good reason. As the men and women of the Winter Games skate, ski, shoot, jump and curl their way to glory, the winning margin is getting sliced thinner than the smiles on the faces of athletes who finish fourth. "As records get broken by smaller and smaller blocks, we must be approaching a limit on human performance," says biological anthropologist Daniel Schmitt of Duke University.
That means taking a close look at gear. Americans Chris Witty and Casey FitzRandolph will wear the lightest boots in the speed-skating rink, called K2 Mod X. A whopping 50 grams (just under two ounces) lighter than the standard clap skate, it could shave centiseconds off their time. American snowboarders will be half-piping on a surface of indium. Bonded to the business side of the board, the silvery metal could make the boards some 2 percent speedier. The reason is that indium freezes at 23 degrees, just above the point where snow becomes "grabby," as engineer Scott Barbieri says. That lets the indium absorb the heat generated by friction with the snow, rather than allowing that heat to warm up the board: a warm board means melted snow, and melted snow for a snowboarder might as well be Velcro.
If anyone sniffs that none of this sounds like rocket science, take a look at the latest in alpine skis--designed by rocket scientist Thomas Highsmith of Thiokol Propulsion. It's called Molecule Liquid Graphite, and the U.S. Ski Team will put it on their ski bottoms before they wax up. The layer of graphite prevents ski-slowing static from forming between the fluorocarbon overlay (the stuff atop the wax) and the snow. On the hockey rink, many German and Czech players are wearing a skate with a sharp "t'blade," which is thinner than the standard one. As a result, the blades heat up more quickly, create an instantaneous film of water underneath as they go and thus cut friction some 40 percent--putting the "fast" back into fast breaks.
The notion of speed skaters "flying" will be more than a metaphor at these Games. Long-track and short-track speed skaters from the Netherlands, Australia and the United States will don a new head-to-toe aerodynamic speed suit designed by Nike on the same principles that make golf balls soar. The designers put life-size mannequins and speed skaters into wind tunnels to determine the pattern of air flow in various postures, and then went back to the lab to match fabrics to ideal flow. The torso and hood assume a wing shape when the skater is bent almost horizontal from the waist. "There, you want a smooth fabric so the air flows easily over the 'wing'," says Nike designer Rick MacDonald. But on the forearms and shins, which present vertical profiles to the airflow, smooth flow creates a wake in back. That causes "pressure drag," a situation in which pressure is lower behind than in front, slowing a skater. In contrast, the turbulent flow generated by textured fabric churns up the air like dimples on a golf ball, reducing wake and therefore pressure drag.
Gold medals don't come only from stuff, of course. At the Olympic level, a subtle variation can have a huge effect. "A little bit more skill is a hundredth of a second, and that does make a difference," says Duke's Schmitt. Where might that physiological edge come from? "Anywhere from 50 to 80 percent of a certain athletic capacity could be determined by your genetic inheritance," says Farshid Guilak, a professor of biomechanical engineering at Duke. Biologists are now identifying these traits quite specifically--that is, they've gone way beyond talking vaguely about genes for speed. The best-known natural difference is the proportion of fast- and slow-twitch muscle fibers you're born with. Fast-twitch fibers, as the name indicates, are able to fire, relax and then fire again very rapidly. They produce "a tremendous amount of power," says Schmitt, but tire quickly. Slow-twitch fibers, on the other hand, are the Energizer Bunny of physiology: they keep firing, and firing, and firing... but only with a relatively long (though still measured in fractions of a second) relaxation period in between. As a result, being born with a preponderance of fast-twitch fibers makes you a natural sprinter; slow-twitch fibers equip you for endurance events like cross-country skiing. Slow-twitch fibers also contribute to balance, so figure skaters need both--slow-twitch to stay standing during long spins, and fast-twitch for jumps. An average mortal has half slow-twitch and half fast-twitch. Training can change the proportion only a few percent.
As researchers identify genes that correspond to athletic excellence, some sports scientists are openly asking whether the next doping scandal will involve not drugs but genes. At a Genes in Sport conference in London in November, biologists warned that "within the near future" a new way to cheat will appear. This new method is "gene doping." Instead of shooting up with banned substances, competitors might receive injections of genes carrying instructions for the production of such substances. In monkeys, a single gene injection raised the hematocrit, the number of oxygen-carrying red-blood cells, between 40 and 70 percent. Since the injected gene would produce substances identical to those made by the body naturally, gene doping would be tough to catch. Another possible gene dopant: the ACE (for angiotensin converting enzyme) gene. Found on chromosome 17, it comes in a long and a short version. Those with the long form seem to excel at endurance events, like mountain climbing and long-distance speed skating. In power sprints, like the bobsled start and short- and middle-distance speed skating, the short version confers an advantage in strength and power. If the winning edge keeps coming from tech and genetics labs, maybe the scientists deserve a gold medal.