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"   Alpine Skiing Carving Turns at 50 mph  Olympic skiers subject their bodies to as much as 3.5 g&amp;#039;s--more than space shuttle astronauts endure during launch--and to velocities that would earn them speeding tickets in most states. And when steep sections of a run flatten out, it takes a world-class athlete to stay upright despite the downward inertia. &amp;quot;A lot of us can leg-press 900 pounds, but that&amp;#039;s easy compared to this race,&amp;quot; says Ted Ligety, a Park City, Utah, native and reigning Olympic gold medalist in the combined skiing event, which is based on the total time from one downhill and two slalom runs.  For the 2010 Olympics, Ligety is focusing on the slalom and giant slalom events. The slalom course is 2507 feet long, with 65 gates and a vertical drop of 722 feet. The giant slalom event has about 10 fewer gates in a course of more than twice the length (5256 feet) and vertical drop (1476 feet). Both events demand that athletes master a high-speed onslaught of gravity, friction and inertia. Skis  Ligety&amp;#039;s Rossignols are made of a wood, fiberglass and metal laminate. Shorter skis enable competitors to make quicker turns; longer skis generate more speed. Minimum lengths: 165 cm for the turn-filled slalom; 185 cm for the giant slalom. Knees  Alpine skiers&amp;#039; knees sustain about 110 ft-lb of lateral torque during turns and nearly 300 pounds of total force at the joint--almost as much torque as can be found in the engines of a ski resort&amp;#039;s snow-removal trucks.  Turns Skiers generate enough g&amp;#039;s in turns to make a 180-pound athlete--like Ligety--feel like he weighs more than 600 pounds. Steep angulation of the legs and an upright torso generate greater energy and speed coming out of the gates.  The Course  For the men&amp;#039;s giant slalom, the gradient peaks at nearly 40 degrees on the Dave Murray Downhill Course at Whistler Mountain (above). Skiers carve blind turns at 50 mph and fly down straightaways at up to 90 mph.  Ice Hockey Firing Pucks at 100 mph   David Backes, forward, St. Louis Blues, U.S. Olympic team. (Photograph by Getty Images) When a player blasts a slap shot 30 feet from the net with 125 pounds of force, the goalie has less than 200 milliseconds to react to the flying 3-inch-wide, 1-inch-thick puck. &amp;quot;The physics of it are astounding--even to me,&amp;quot; says U.S. team hopeful David Backes, a forward on the St. Louis Blues. Backswing At the height of the windup, the player&amp;#039;s hands are 15 to 23 inches apart, and the chest, shoulder and arm muscles are stretched and ready to contract.  Preloading  Milliseconds before the blade hits the puck, it scrapes the ice about a foot behind the hard rubber disk. The stick bends up to 30 degrees, which preloads it like a spring, providing 50 percent of the shot&amp;#039;s velocity.  Contact  Preloading also extends the length of time the blade is in contact with the puck, which increases the shot&amp;#039;s acceleration. For elite players, contact can last 40 ms. In baseball, bat-on-ball impact lasts less than 1 ms. Stick Personal preference dictates whether a stick is made of wood, Kevlar, graphite, carbon fiber or aluminum. Backes uses a composite model that bends low on the shaft, giving him a quicker shot release.  One-Timers  When players shoot a moving puck, they tap into that existing velocity and add a few mph to their own shot.    Biathlon Rifle Shooting at 170 bpm    20-km Event Order: Ski 4 km --&amp;amp;gt; Prone Shooting --&amp;amp;gt; Ski 4 km --&amp;amp;gt; Standing Shooting --&amp;amp;gt; Ski 4 km --&amp;amp;gt; Prone Shooting --&amp;amp;gt; Ski 4 km --&amp;amp;gt; Standing Shooting --&amp;amp;gt; Ski 4 km . (Illustration by Gabriel Silveira) Competing in the Biathlon requires both endurance and world-class shooting skills. Athletes must ski 20 kilo\u00ADmeters with a rifle and stop four times to shoot at targets, alternating prone and standing positions. The .22-caliber rifles have no optical sights, and missing a target can mean skiing a 150-meter penalty loop. Former U.S. team member Shaun Marshall-Pryde once compared the event to &amp;quot;climbing 25 flights of stairs and then threading a needle five times without missing the hole.&amp;quot; Success requires tremendous conditioning: Within seconds of arriving at the ranges, athletes must bring their heart rate down by about 20 beats per minute in order to shoot with a steady hand.  Heart Rate  The skiing portion of the biathlon brings an athlete&amp;#039;s heart rate up to 190 beats per minute. The target heart rate when shooting: 170 beats per minute. Rifle  The rifle&amp;#039;s straight pull bolt is opened with the index finger and closed with the thumb. The shooter never has to change position--and can pull his five shots in 20 seconds or less.   (Illustration by Gabe Silveira) Weight  Rifles must weigh at least 3.5 kilograms (about 7.7 pounds). &amp;quot;A heavier barrel is harder to ski with, but has less vibration and is more accurate,&amp;quot; says Jack Sutton of Hart Rifle Barrels. Stock American Olympian Tim Burke traded his rifle&amp;#039;s original walnut stock for one made by a German wood\u00ADworker. &amp;quot;The rifles are so individualized, you couldn&amp;#039;t compete with a teammate&amp;#039;s,&amp;quot; he says.  Figure Skating Spinning Gracefully at 420 rpm   &amp;quot;Girls did triple axels, then triple-triple combinations, and in the future they&amp;#039;ll definitely be doing quads.&amp;quot; - Rachael Flatt, U.S. Olympic hopeful  A demonstration of power and grace, this event may be scored at the whim of judges, but it is governed by irrefutable laws of physics. Launch  Female skaters hit 20 mph, then push off with one leg, applying a force nearly four times their body weight against the ice as they attempt to propel their center of mass 12 to 16 inches upward.  Flight  A 45-degree jump gives skaters 0.55 seconds of air time--enough to complete all but the devilish triple axel, which requires 0.65 to 0.75 seconds and a spin rate of 420 rpm--the engine-idling speed of some cars. Landing  Skaters tweak tight landings by flexing hips and knees and sinking their center of mass--thereby earning a few hundredths of a second of hang time and an extra 10 to 20 degrees of rotation--before landing with a force of up to 12 times a skater&amp;#039;s weight.  Curling Sliding 42 Pounds of Granite   Every ice surface plays slightly differently, and even the crowd at Vancouver&amp;#039;s new 5600-seat curling arena will affect shots. &amp;quot;When it&amp;#039;s packed, there will be more heat in the building, and the ice could get softer and slower.&amp;quot; --Phill Drobnick, U.S. Men&amp;#039;s coach In curling, teams slide 42-pound granite stones down an ice sheet toward a target. On dry surfaces, the front of a spinning sphere generates more friction than the back, and the sphere veers in a direction different from that of the rotational vector. On ice, the opposite is true: A liquid layer reduces frontward friction, and the stone spins and slides in the same direction. This is where the sweepers get involved. Two players use brooms to scrub the ice ahead of the stone, enhancing the liquid film in order to adjust curl (how much the stone veers to either side) and the length. The U.S. squad&amp;#039;s tests have shown that sweepers can &amp;quot;drag&amp;quot; a stone up to 16 extra feet. Ice Surface  Unlike the smooth surface used for skating, curling ice is dimpled with tiny drops of frozen water--or &amp;quot;pebbles&amp;quot;--that create friction with the stone and cause it to curl.   Ski Jumping Flying 450 Feet   Laminated foam ski jumpsuits are one of the sports world&amp;#039;s most tightly regulated pieces of equipment. The reason: Even small tweaks to surface area can add lots of lift. &amp;quot;People were tinkering with the suits and flying like bats,&amp;quot; says Troy Flanagan of the U.S. Ski and Snowboard Association. So the International Ski Federation standardized the gear. Suits can now be no more than 5 mm thick; the underwear, 3 mm. And, since airtight suits function as sails, the rules require materials that allow 40 liters of air per square meter to flow through them per second.  Bobsled Banking Turns at 95 mph    The U.S. team barrels around a bend in a Bo-Dyn ride called Night Train.  In 1992, former Daytona 500 champion Geoff Bodine dedicated himself to rebuilding American bobsledding. With the help of car designer Bob Cuneo, he formed the Bo-Dyn Bobsled Project and began building custom sleds to replace the retread imports the U.S. had been using. &amp;quot;Now the Italians are working with Ferrari; the British have McLaren; the Swiss have gone to Audi,&amp;quot; Cuneo says. &amp;quot;But we were the first team to acknowledge the crossover between race cars and bobsleds.&amp;quot; Bo-Dyn engineers have spent nearly two decades improving the suspension, streamlining the sled body and studying metallurgy for the steel runners. The payoff: The U.S. team won its first world championship in 50 years last February. Ultimately, Cuneo estimates that about a third of the team&amp;#039;s success in Vancouver comes down to engineering.  The Course    The Whistler Sliding Centre on Blackcomb Mountain (right) is the world&amp;#039;s steepest bobsled track. It drops 500 feet over a distance of 4757 feet, a gradient that generates speeds of up to 95 mph. Body  The sled&amp;#039;s 462- pound body is a proprietary blend of fiberglass, Kevlar and carbon fiber. The U.S. team enlisted supercomputing firm Exa to model the sled&amp;#039;s fluid dynamics in order to minimize drag-inducing air vortexes that form behind riders&amp;#039; heads. Chassis and Suspension To minimize energy-bleeding vibrations, Cuneo&amp;#039;s team continuously adjusts the steel chassis and torsion-bar suspension for weather, track conditions, metal fatigue and stress from the g-forces. "^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.popularmechanics.com/adventure/sports/a5347/4345010/>