He developed an astounding repertoire of aerial tricks and jumps. Then in 2007, a video he created to showcase his abilities won first prize in a competition sponsored by a popular freeskiing website.
Now, just seven years later, Wallisch is the biggest name and talent in the burgeoning discipline of slopestyle, one of the X Games-like events making their Olympic debut at Sochi.
"It's happened so fast," said Wallisch of the inclusion of a sport born in the 1990s. "It's just grown exponentially."
He ended 2013 as the world's top-ranked slopestyle performer, having won X Games competitions in America and Europe.
And, barring serious injury, this lifelong thrill-seeker will not only be named to the 2014 U.S. Olympic team later this month but will be a favorite to win the event's inaugural gold medal.
Not bad for a Pennsylvanian who began skiing on a 700-foot hill in western Maryland, where his ski-enthusiast parents had a condo.
But traditional skiing and its restrictions soon bored him. That's when, through the X Games and their recent Olympic exposure, Wallisch found extreme skiing.
"I wanted to find a way to scare myself and get a rush," he said. "And that became catching air, building jumps . . . and experimenting."
For those whose ski knowledge ranges from Lindsey Vonn to Bode Miller, slopestyle more closely resembles snowboarding than traditional skiing.
Competitors speed down a hill, utilizing hills, rails and walls to perform a series of jumps. The more daring the completed leaps, the better the scores.
"I really think slopestyle is fascinating because someone like me, who grew up on a small mountain, can still excel," he said. "The size of the hill doesn't matter. All that matters is the kind of jumps and rails you can find or build."
The emergence of slopestyle - and its close cousin half-pipe skiing - as an Olympic event is emblematic of a winter-sport revolution.
Intrigued by the growing popularity of these new extreme sports, the International Olympic Committee last year moved quickly to add slopestyle and half-pipe to the Sochi lineup.
With few winter sports able to capture a broad TV audience, Olympic officials sought ways to broaden viewership beyond traditional draws like figure-skating and hockey - especially in the vital American market.
Their youthful appeal and anti-authoritarian aura, have quickly gained them a surprisingly large base.
According to a recent survey by Snowsports Industries America, 46 percent of U.S. skiers now classify themselves as "freeskiers".
"These sports are in a transition from being a lifestyle to real world-class sports," said Kelli Clark, 30, a two-time Olympic medalist. "I grew up a ski racer but for a 10 year-old it was too structured and intense. In our sports, there's more room for self-expression and creativity."
Equally important for the United States, especially in what promises to be an off-year for its figure skaters, there's also the prospect of additional Olympic medals.
"We're in the business of helping make the U.S. as strong as possible," said Mike Jankowski, the Americans' snowboarding/freeskiing coach. "So we worked at adding medal events [that we excel in]. It's the right thing to do for the youth and for the sports."
Freeskiing, as Wallisch's story demonstrates, needn't be confined to ski slopes. He's used chunks of metal, wood and barrels in his backyard to launch himself.
And since rails are such an important element, skiers like him roam the world's cities looking for suitable ones to mount.
"We call it urban skiing," he said. "We look for creative, progressive things to do, things you would never see a [traditional] skier doing. I've skied rails in major cities around the world. Pittsburgh. Minneapolis. Boston. New York. Stockholm. Moscow."
Last year, with the aid of a documentarian, he completed a film on urban skiing, The Wallisch Project.
"This is what the kids are doing at resorts, and these sports have American roots," said Tom Kelly, communications vice president for the U.S. Ski and Snowboard Association.
If Alpine skiers are lone wolves, traversing the world's luxury winter resorts, free-skiers and snowboarders are the outsiders, the interlopers.
And, being younger and more plugged in to contemporary culture, they've made social media and the Internet vital components of their sports.
There's no better example of that than Wallisch, who is an Internet superstar among slopestyle's devotees.
"I just grew up in a Golden Age for all that," he said. I came onto the scene at the same time Facebook and YouTube were exploding. We've been putting out edits [videos] for seven years and I've been able to develop quite a following."
A business major at the University of Utah, not far from the ski-resort town of Park City where he now resides and trains, Wallisch has collected enough followers and sponsors to earn a living - and to contemplate a future as a marketer for his sport.
"The way this thing is growing, and given my educational interests, I can really see myself doing this into the future," he said.
"My goal is to ski as long as possible."