Speedskater suit to let racers go with the airflow


OSAKA — During the four years since the 1998 Winter Olympic Games in Nagano, athletes have tried hard to improve for next month’s games in Salt Lake City.

News photoA Mizuno employee shows off part of a speedskating suit featuring the firm’s newly developed Aero Dot fabric that its maker claims can shorten the lap time of a top 500-meter skater by 0.8 seconds.

Although not an athlete himself, Tatsuo Sakaguchi has tried just as hard to help improve speedskaters’ performances, and he appears to have succeeded in time for the Games.

Sakaguchi, a product development employee at Mizuno Corp. — Japan’s largest sporting goods manufacturer, headquartered in Osaka — has developed with his three colleagues a suit for speedskaters that would, in theory, improve the record of a top 500-meter skater by 0.8 second — a great margin in the world of speedskating.

When Hiroyasu Shimizu of Japan won a gold medal in the men’s 500 meters at the Nagano Games, his aggregate time was 1 minute, 11.35 seconds from two races in which he clocked 35.76 and 35.59 seconds, while the silver medalist, Jeremy Wotherspoon, of Canada, clocked 36.04 and 35.80 seconds, for an aggregate of 1 minute, 11.84 seconds. Therefore, the difference of 0.8 second can be big enough to determine the color of the medal.

The secret of the suit, called the Aero Dot, can be seen in three areas — but only if observed very carefully.

A mass of silicone resin is spread out in tiny dots at the head, the back of the shoulders and on both sides of the shins. These dots, each less than 1 mm in diameter and less than 0.3 mm high, are placed in a beltlike shape that is less than 3-cm wide.

According to Sakaguchi, who has been developing various types of athletic wear, the aerodynamic theory applied to this suit is nothing new; it has been studied at Mizuno since the early 1980s.

About 90 percent to 95 percent of the air resistance on the human body is caused by its shape. While body shape cannot be streamlined, as with airplanes or cars, the air resistance on the body can be lessened by placing a certain material at a point where the air flow comes off the body, he explained.

Air resistance is caused by turbulent air flow that occurs right after the flow comes off an object. If a certain material is placed at a point where the air flow comes off, the turbulent flow of air occurs further back, subsequently lessening air resistance. That is what the dots do to the air resistance on the body, Sakaguchi said.

“This logic has long been applied to ski-jumping suits and cyclist suits, but had been thought ineffective for speedskating because speedskaters’ body movements seemed too volatile for the principle of aerodynamics to make a difference,” he said.

But coaches and skaters told Sakaguchi that although their arms are moving in many directions, the movement of the legs is specific and limited. Therefore, the aerodynamics could be effective. So he began to work on developing new gear soon after the Nagano Olympics.

The optimal location of the silicone dots was roughly figured out last year with a prototype. The effect, in terms of lap time, was confirmed last March when Shimizu set a new world record of 34.32 seconds — 0.31 second faster than the previous world record set by Wotherspoon in January 2000.

The weight of the suit was also lessened by 30 percent, resulting in Shimizu’s model weighing only 200 grams.

“At Nagano, it was thought that a tight suit would enhance the power of skaters. But skaters requested a suit that would make them feel as if they were wearing nothing. So we made it very stretchable and light,” Sakaguchi said.

Olympic Games are the best places to promote sporting goods and the technology of their manufacturers, but manufacturers have a dilemma.

“Although we are confident that our finished products contribute to the improvement of skaters’ lap times, we can never tell how much of an effect they have, even when the skaters perform well,” he said. The manufacturers also do not necessarily play up their products’ effects because some athletes do not like to attribute their results to the gear they wear.

The Aero Dot suits, however, have earned a sound reputation among Japanese skaters, Sakaguchi said.

“Long-distance skaters, especially, say that they do not hear ‘the sound of wind’ when wearing the new suits. . . . The better products may also give a psychological boost to skaters, helping them feel as if they have an advantage.”

Sakaguchi, however, may not be as patriotic as other Japanese during the Olympic Games, since Mizuno has contracts with Japan’s national skating team as well as the German and Russian teams.

“My colleagues and I will be shouting ‘Go, Go’ to any speedskaters wearing our new suits in Salt Lake City,” he said.