Why Speed Skaters Perform Better At Higher Elevation

(ISNS) -- Speed skaters move so fast that air resistance is a major factor in each race. At the low, near-sea-level elevation of Sochi, Russia, air resistance will be too high for competitors at the 2014 Winter Olympics to set any new world records, experts predict.

All world records in men’s and women’s traditional, long-track speed skating, from 500-meter sprints to 10,000-meter races taking more than 12 minutes, were set at tracks in cities more than 3,400 feet above sea level. The majority of Olympic records were set 12 years ago, in Salt Lake City, Utah where the track sat 4,675 feet above sea level. The only Olympic record set in Sochi thus far came in the men’s 5,000-meter, from the Netherlands’ Sven Kramer, but that time was more than 7.4 seconds slower than his 2007 world-record-setting performance in Calgary, Alberta.

“It’s a little counterintuitive because we usually think altitude slows people down, but in speed skating, it’s the other way around,” said Robert Chapman, an exercise physiologist at Indiana University, in Bloomington.

Competitors in many events fare worse at higher altitudes. Their muscles rely on the oxygen they breathe for fuel. But at high altitude, there’s just less of it, which means their muscles can do less work. Speed skaters, however, perform better at high elevation despite competing in an environment that contains less oxygen.

When speed skaters reach top speed, they travel over 30 mph. The air resistance they face is considerable. Think of reaching your hand out of a car window while driving at that speed.

Due to the near-sea-level elevation, the air at the speed skating oval in Sochi is denser than at venues with higher elevations. That dense air means higher air resistance against fast-moving objects, like a speed skater. That high air resistance works against a speed skater, requiring the skater to exert more effort to reach and maintain the same speed as in a location with lower air resistance.

A skater could give the same performance in terms of effort and technique, but go faster at a higher elevation. That means the same skater, skating just as well for a 500-meter race might go more than half a second faster in Calgary than in Sochi. Over a long race such as the 5,000-meter, the effect adds up to several seconds.

This means that the optimum conditions for speed skating include not just perfect ice and carefully sharpened skate blades , but a relatively high elevation, too.

“People think somewhere between 5,000 and 7,000 feet there may be a sweet spot where the decline in maximal oxygen consumption is more than made up for by the better aerodynamics,” said Michael Joyner, a physician-researcher at the Mayo Clinic, in Rochester, Minn., with a special interest in the physiology of endurance performance.

He pointed toward bicyclists, who also tend to set their speed records at higher elevations.

“Some of the cycling records have been set at the Velodrome in Mexico City. You’d think that’d be the last place you’d ever want to go to set a record because your oxygen consumption would go down,” said Joyner. “But in fact, your wind resistance goes down more than your oxygen consumption goes down.”

This is why optimal aerodynamics is such a big issue in speed skating. It’s why the competitors wear skin-tight suits, and why they skate in a deep crouch, attempting to minimize the air resistance they face, no matter the altitude of their race.

Sochi sits at about the same elevation as Vancouver, the site of the 2010 Winter Olympics. Chapman said the performances might be a little better this time around, due to factors such as improved technology, even though there likely won’t be world records.

Chris Gorski is a Senior Editor for Inside Science and tweets at @c_gorski .