If you watch the speed skaters during this year’s Winter Olympics, you’ll certainly notice something strange about the footwear they’re sporting. With a hinged blade that moves independently from the boot, modern speed skates look nothing like hockey or figure skates—they're clap skates. What’s the purpose of such freaky footgear?
Clap skates were invented almost a hundred years ago, but it took until the last few decades for them to gain traction in the competitive sport. “The modern day clap-skate was developed by a Dutch group in the mid 1980s,” says Scott Van Horne, a former Canadian national speed skater who has studied the biomechanics of skaters using clap skates.
“At first the elite skaters wouldn’t touch them,” Van Horne says, but in 1996, some of the Dutch women’s team took a chance, and switched over. The results were astonishing—everybody in the sport noticed. “Suddenly skaters you might otherwise deem ‘hacks’ were now using clap skates and contending for the podiums,” Van Horne says.
By 1997, clap skaters were breaking world records, and “by the next year everybody had switched,” Van Horne says. At the 1998 Winter Olympics in Nagano, Japan, speed skating was dominated by the footwear—and has been ever since.
Although these new skates were shaving precious seconds off the Olympians’ times, for a while, nobody really knew why.
“Originally people thought the skate helped reduce friction,” Van Horne says. “With the traditional skates, it used to be that at the end of your stride, you’d push up on to the front of the skate’s blade. You could even see the ice fly into the air.” Conversely, on a clap skate, the blade keeps flat contact with the ice throughout the entire stride.
But as much sense as that makes, reduced friction isn’t really why clap skates are so effective. “Basically what clap skates do is give a more advantageous position for generating power at the knee,” Van Horne says. With the old skates, pushing up on to the front of the skate’s blade meant that the skater’s knee was absorbing a tiny bit more of his/her energy—about 5 percent, according to Van Horne. Pretty small, he admits, but just enough to make a big difference out on the rink.