Despite the icy air of the late October afternoon, Todd Griffiths strips down to his skin-tight spandex uniform and lifts himself atop a bay horse named Darby. His legs move forward and in one fluid swing are back behind him, pulling him into a handstand, part of a warmup before he gives us a full display of his vaulting skills.

Vaulting is not a widely known sport in America. So tell an equestrian that you know a vaulter, and he’ll be impressed. The activity is a combination of gymnastics and dance performed atop a moving horse, so amazing, it’s hard to tear your eyes away. The art dates back at least to the Middle Ages, when it was used to display the agility of noblemen and knights.

Today vaulters perform a repertoire of gymnastic moves, including straddle jumps, splits, lifts, backward stands, and leaps, all over the vaulting saddle of a horse cantering in a 15-meter circle.

A third-year veterinary student at Washington State University, Todd is one of the nation’s top vaulters. Last summer he competed on the U.S. team at the World Equestrian Games in front of 6,000 screaming, cheering people in Aachen, Germany. And now he has his sights set on the World Games in 2010.

He was born to horses, having grown up on a ranch in Montana. “I don’t know why, but I have always tried to do tricks,” he says. On long cattle drives, he would kneel or stand in the saddle. The result was usually disappointing. “The horse would just stop,” he says. “It couldn’t figure out what I was doing.”

At five-foot-five, Todd is a wiry guy and a natural at gymnastics. He pursued the sport through high school and into college at Brigham Young University. He discovered vaulting when a classmate urged him to try some moves atop a horse. Vaulting horses are trained to have a gymnast on their backs, and when guided by a longeur who is cracking a whip and pushing them to canter in circles around the arena, make for a moving platform. “I had to go try it,” says Todd.

Some moves, like handstands, he could do right away. “But some things were more difficult than I expected,” he says. “I tried something as simple as sitting on a horse sideways, and I fell right off.”

But he took to the sport, continued it through college, and then through his first years studying veterinary medicine at WSU. He found a practice partner in Darby, an older resident of Wonder Stables in Pullman. Though the horse had never been vaulted on before, he had a steady gait and an easy temperament, ideal qualities for the work.

Our afternoon watching Todd vault comes during a break from his studies. He plans to become an equine surgeon. He traded his lab coat for his spandex to give us a firsthand view of the sport. Having warmed up a little, he leads the horse into a small, fenced arena and hands the line to the horse’s owner, who has agreed to longe for him.

As Todd stands, his knees bend to accommodate Darby’s movements. He throws his arms wide, holds for a few seconds, and then jumps down to the saddle, patting the steed’s neck. The longeur’s whip cracks, urging the horse speed up.

Todd stands again, bends at the waist, puts his right hand on the horse’s back and lifts his left leg skyward. He holds his pose as the horse moves forward.

Next, he tries a handstand on the arms of the vaulting saddle; then he bends his elbows and curves down into a perfect C over the horse’s neck.

For his big move, he has to forget gravity. Standing on the saddle, arms in the air, he hops a little, as the horse sinks in the canter. His arms curve to the front, his knees bend, and then he springs high, free of the saddle, about four feet off the horse. He does the splits, hangs for a second, and then descends, landing softly, sliding his feet down the sides of the horse. The photographer and I gasp. Todd looks over and grins. “Sometimes it feels like you’re getting bounced out of control,” he says later. “But sometimes it really does feel like you’re flying.”