Olympic Skiers Rely on Chemistry to Improve Race-Day Performance

Olympic athletes get a little help from chemistry, in the form of ski wax. The wax they select can mean the difference between getting a metal and coming up short.

Olympic Skiers Rely on Chemistry to Improve Race-Day Performance
  Jörg Angeli

Olympic athletes provide inspiring examples to youth during the Olympics through their dedication to mental preparation and physical training. A little help from chemistry doesn't hurt either, in the form of ski wax selected by ski techs — unless you use the wrong kind of wax to crash and burn instead of scoring a gold medal.

Olympic skiers use ski wax underneath their skis to produce fast rates of speed, and the type of wax chosen depends on the consistency of the snow, among other considerations. Drier fluff requires a different wax than wet snow, and the kind of skiing also matters — downhill and cross-country skiers require different wax types. That's where chemistry comes into play.

What Goes Into Ski Wax?

Similar to natural gas and gasoline, ski wax is made up of various hydrocarbons consisting of both hydrogen and carbon atoms in a chain. The first wax layer a skier may apply is like candle wax where it adheres to the ski bottom to block water and dirt.

Fluorocarbons make up the next layer, combining a recipe of molecules created from hydrogen, carbon, and fluorine. This wax mix produces the key to ski speed, cutting friction between the snow surface and skis. The chemical recipe is also similar to the kind many manufacturers use for rain gear and its ability to repel water. Fluorocarbon waxes are softer than other waxes, and they’re often used as powders or fluids.

Known as a skier's best friend for speed, fluorocarbon mixes have a downside: Ski techs possess blood level PFC concentrations about 45 times that of members of the general public from emitted gases absorbed by the body as they produce fluorinated ski mixes. Researchers worry the environment may be at risk. Animal studies have revealed negative effects on the endocrine and immune systems, but more research is needed.

Different Formulations for Various Races and Weather Conditions

Skiers need different formulas of wax depending on what type of race they're participating in. Skiers aim for a more slippery surface when racing for two minutes downhill. Other skiers will layer wax six or more times as they race two hours for a cross-country event. Multiple layers provide more grip and slip as they move uphill and downhill.

A few fluorocarbon formulas contain extra hydrocarbons — such as toluene or acetone — and harmful chemicals. So, skiers and techs must be careful not to touch or breathe in the formulation as they apply the mixture to their skies. These formulas are applied multiple times during races.

Getting the wax right is key to earning the gold. Getting the kick wax correct for gripping the upward hill climb and keeping pace is vital, according to four-time Olympian Jean-Marc Chabloz. He says there are four factors to consider when waxing: snow quality, humidity, temperature, and distance. Skiers can have a good grip when they test out the wax, but during the race, conditions quickly shift.

When the wax goes wrong, the blame falls on those in the wax cabin for the mishap of how the formula was chosen and applied. Hydrocarbon wax is best with watery snow, for example, but waxes risk stickiness when misapplied. Hydrocarbon and fluorocarbon waxes are typically iron-on types, but waxes may be applied in powder and liquid form by using a cork to rub them into ski pores.

The base of the skis are composed completely of high-density polyethylene (C2H4), called P-Tex to skiers, and is basically a long chain of carbon atoms. Higher molecular weight polyethylene (UHMW) is used beyond recreational skiing, as it resists abrasion and is porous, making it the perfect material for waxing.

Skiers and Wax Techs

Cross-country races contain two basics types of techniques: freestyle where the skier skates and cross-country skiing as a diagonal or kick-and-glide approach. Skiers in a skiathlon will typically start the first half in the classic kick-and-glide and finish in the freestyle. Unlike other races, skiers swap out of skies with grippy waxes for slippier-waxed skis midway through for a quick finish through the freestyle portion.

Olympic ski teams don't necessarily go out and buy specific brands — they create their own highly secret formulas best-suited to the snowy terrain and their skier. In fact, their cabin staff contains 30 or more techs helping to divine the correct wax formula.

Famed “Wax Chief” Knut Nystad of the Nordic team says he's only known in the newspapers when he and his team misjudge the right wax, such as in the 2014 Sochi Olympics when the country didn't place in either relay — never mind that the team fared well in games before and after this one-off mishap.

This year, Norway met with success with three medals gloriously collected in the 15-kilometer + 15-kilometer skiathlon. In the wax cabin, the team relaxed and made scientific notes while sipping espresso. Since they've come to expect the pressure, the Norwegian ski wax techs can do nothing but collect themselves at the end of a long day of what looks like wax wizardry. The science notes come in handy for next time.

Waxing to Win

Instead of feeling like they’re trekking mud, no matter if the formula is hydrocarbon or fluorocarbon, the goal is to transform skis into a powerful form of Alpine transportation that looks motorized but isn't as the skier glides and grips accurately all the way to a gold medal.

The audience witnesses a gold medal Olympian skiing to a solid win in cold temperatures. Who knows what the snow feels like underfoot?

Is it wet and mushy? Is it fluffy? What are the humidity levels? At what distance does the skier need more grip? Wax techs are behind the scenes asking these questions and more to tweak their wax formulas for race day, though they're rarely seen in the headlines — unless their wax wizardry fails to achieve gold medal status.

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Wax techs consider thousands of wax formulas, grinds, and powders stored in databases to apply to skis in weather conditions liable to change in as little as an hour. Skiers are met with various types of snow at different points in the race. Applied wax layers must provide the right glide and grip.

Now you know the truth. Teams of ski tech alchemists work to transform ski wax into gold engaging in art and science. Sometimes, they arrive weeks in advance of the big event to test the conditions and consider the various elements of chemistry needed to take home an Olympic medal for their country. When the wax is right, ski techs put athletes on the fast track to Olympic gold.

Megan Ray Nichols is a blogger and freelance science writer. She enjoys participating in conversations about engineering, technology and space exploration. Megan is also a regular contributor to Datafloq, Cerasis, and American Machinist. When she isn't writing, Megan loves watching movies, hiking, and stargazing. Subscribe to Schooled By Science today to keep up with scientific discoveries or follow Megan on Twitter.