A top rival of 2006 Olympic gold medalist Shaun White, Pearce was among U.S. snowboarders preparing for an Olympic trials event next week, in advance of the Winter Games in February in Vancouver.
The Vermont native was executing a "double cork" maneuever -- a twisting, double back flip that is the latest evolution of the sport and represents an effort to keep up with White. "He did it a little too hard, put a little too much oomph into it, and over-rotated on the second flip," U.S. coach Mike Jankowski told The Times .
During the recent U.S. Olympic Media Summit, Pearce cited how the bigger halfpipe to be used in the Vancouver Games would allow more time in the air, resulting in more demanding tricks. "The progression is moving so fast ... we're going to see halfpipe riding on a whole new wave this year," he said.
Pearce sustained a concussion in mid-December during a qualifying run at the Copper Mountain Grand Prix, ESPN reported.
Pearce is among seven members of the "Frends" -- the missing "i" is intentional -- snowboarding group, who have banded together in an effort to emphasize the fun, less commercialized roots of the sport. They consider themselves collective rivals to the more famous White.
The Frends began working on the double cork last spring at Mammoth Mountain, Calif., where Pearce was scheduled to compete next week.
"New tricks are bound to happen every year and it keeps getting a little heavier because the tricks are more dangerous," Danny Davis said. "You just have to step up and learn them, keep pushing yourself."
Pearce topped White for the gold medal in the 2009 European Open, while finishing a strong second to him in the Winter X Games.
"I've been able to beat him a couple times and even though he's beaten me a lot more times, it still kind of feels like I'm coming up to his level," Pearce told NBCOlympics.com.