It's remarkable how a youthful passion can become a life's work. For one fashion entrepreneur, skateboarding has led to a global footwear brand and help for the homeless. Pierre André Senizergues, president, owner, and CEO of California-based sportswear giant Sole Technology, grew up 10 minutes from Paris, where he skateboarded through the catacombs and around the Eiffel Tower. This was one hip kid back in the 1970s. But as Senizergues recounts, the sport peaked at warp speed and faded just as quickly. "It was this phenomenal trend and then a year later it left, and everyone hated the fact that it became so big and then so small, so it then became very hard-core to be one [a skateboarder]."

Hard-core is an apt description of the sport and the people who enjoy it. One of Senizergues's many achievements is the Sole Technology Institute, which he founded in 2002 at his Lake Forest headquarters. The former world-champion 'boarder took time from his international sales meeting-in Vancouver this year, at the Fairmont Waterfront hotel in late June-to talk to the Straight about why his sport shoes are different.

According to him, it's all about being hard-core-or hard-impact. "Much of [skateboarding] footwear technology has been borrowed from other sports," he says. But for skateboarding, where landing a jump can entail an impact of 17 times one's body weight ("the equivalent", Senizergues notes, "of landing with a parachute"), the rules of engagement shift completely. Needless to say, durability is high on the list of design needs for the four lines of shoes under the Sole Technology umbrella: etnies, etnies Girl, éS, and Emerica, plus the snowboarding-boots line ThirtyTwo. (For exclusive selects, try Livestock [239 Abbott Street], www.deadstock.ca/, or www.soletech nology.com/.)

Sole Technology prizes toughness-so much so that other labels are now picking up on innovations its shoes have featured for years, Senizergues claims. He remarks that one of his early refinements addressed the wear and tear that skateboard grip tape inflicts on the sole of a standard sneaker. "I used an existing rubber compound [tire rubber] to make a longer-lasting sole, so the outsole [of one of my shoes] will last four to five times longer than a regular sole." The spinoff from this, he says, was that parents of teenagers noticed that their kids' footwear absorbed a lot of punishment, and so began buying the shoes themselves.

The differences with other brands don't end there; it's where they begin. Stitches on the shoe uppers, for example, are sometimes triple and quadruple. (Most sport shoes are double-stitched.) Inside the shoe, behind the leather outer, he's included a rubber layer so that any holes in the outside leather or canvas won't reach the foot. And more recently, Sole Technology has developed a shock-absorbing system to protect heels from hard landings.

"I really feel like the skateboard-shoe industry is changing how we make shoes, and Sole Technology is the only one doing research in the biomechanics of skateboarding," Senizergues claims. "Shoes were not being made the right way, so we added a crash pad on the heel of the shoe, more arch support, more memory foam on the outsole so it can absorb and then go back to where it was."

His childhood pastime has led to other projects. Not least on Senizergues's list of accomplishments is his charity work: from helping build one of the world's largest skate parks (a three-acre site in Lake Forest with more than 38,000 square feet of terrain) to his work with underprivileged children to his personal efforts at conserving energy. (He's had solar panels installed on the roof of his company's HQ.) It all harks back to the days he spent 'boarding through Paris. "I would interact with the homeless," he remembers, "and it is a very complicated situation how they got there." Here in North America, Sole Technology has reached out to the less fortunate by giving 2,000 pairs of shoes to the Los Angeles Mission. "It's a community on their feet a lot, and they walk around barefoot." Senizergues now uses much more than his skateboard to create a roar as he travels down the street.