Mikaela Shiffrin competing in the giant slalom in Colorado on Sunday. European Pressphoto Agency


If a bum knee keeps Lindsey Vonn sidelined, the face of Team USA almost certainly will be Shiffrin, a rosy-cheeked 18-year-old from Colorado. Her star rose in February, when she won the slalom title at the world championships in Schladming, Austria. At 17, she became skiing's youngest female world champion since 1985.

Behind her meteoric rise is a strategy that might surprise those parents who schlep their children from mountain to mountain every weekend in search of glory on the junior ski-racing circuit: As a kid, Shiffrin didn't race much.

While other junior skiers were playing videogames in the back of the family Subaru, Shiffrin was playing outside, zigzagging five hours a day on her home mountain, mastering the near-perfect balance with which she blasts through five dozen sets of slalom gates down icy hills.

Olympic alpine skier Mikaela Shiffrin Reuters


"I think it's misguided, particularly for young kids," said Jeff Shiffrin, Mikaela's father, an anesthesiologist who helped craft his daughter's training and development regimen with his wife, Eileen. "And in skiing, the risk of injury is so high that trying to perform at a level you've never practiced at is asking for a trip to the O.R."

In her first two full years on the World Cup circuit, Shiffrin has raced about 30% less than most of the world's top skiers. Shiffrin pushed out of the starting gate just 28 times last year, down from 30 in 2011-12. Tina Maze, the women's overall champion, started 43 races. Maria Hofl-Riesch, who came in second, started 42.

Shiffrin wants to stay healthy. "I want to ski all events, but slowly," said Shiffrin, who plans to ski both slalom and giant slalom in Sochi. "I want to slowly work into it so I'm not risking injury."

In November, she won the season-opening slalom race in Levi, Finland, by a silly 1.06 seconds, which is like winning the 100-meter dash by 15 meters. The victory earned her a pet reindeer from race organizers. On Sunday in Colorado she won her first spot on a giant-slalom podium, taking second place and missing the top spot by just nine hundredths of a second.

There likely will be more accomplished athletes on the U.S. team in Sochi. Bode Miller is the most decorated male skier in U.S. history. Julia Mancuso has three Olympic medals. But as evidenced by Missy Franklin—the 18-year-old swimmer who won five medals, including four gold, at last year's London Olympics—America can't resist an ingénue who bursts onto the Olympic scene.

"People forget she is still in her 15- to 18-year-old range, so she's still building her foundation athletically," said Kirk Dwyer, Shiffrin's former coach at Burke Mountain Academy in Vermont, who remains one of Shiffrin's snow Yodas. "And more practice is the way to build the foundation."

How young is Shiffrin? Too young to remember Miller dazzling his way to the podium in Salt Lake City in 2002. She was 6 at the time.

Her practice-focused regimen developed under a father who had skied at Dartmouth and a mother who competed in masters races. The family moved to New Hampshire from Colorado when Shiffrin was 8. There she started training at tiny Storrs Hill, vertical drop 300 feet. "I skied at night every night with the Lebanon Outing Club," she said. "It's a tiny hill but you can get a lot of runs in."

The training emphasis was a key factor in the decision to enroll at Burke Mountain Academy, where the Dwyer mantra is practice, practice, practice. Dwyer and the Shiffrins shared an admiration for books such as "The Talent Code" that stress thousands of hours of practice to master any pursuit.

Dwyer models his approach on prodigies in other sports, such as the Williams sisters in tennis and Michael Phelps in swimming. Richard Williams kept his daughters out of most tournaments until their late teens, figuring they would get more out of beating balls back and forth at each other all afternoon than flying across the world to defeat some Bulgarian no-name in 54 minutes. Phelps skipped college and its race-heavy NCAA schedule in favor of a year-round training regimen.

For Shiffrin, that translated into skipping tempting opportunities to prove her mettle against older girls in her early teens. But the dividends are becoming more apparent by the week. In the seven slalom races she has completed since the start of 2013, Shiffrin has finished first, first, eighth, first, third, first and first.

Just 5 feet 7, Shiffrin is shorter and lighter than 5-foot-10, 160-pound Vonn. She doesn't ski with Miller's all-or-nothing recklessness. But technically, Shiffrin is mature beyond her years.

"She is the most stable skier in the world by far," said Steve Porino, the NBC commentator and former U.S. ski team member who also trained with Dwyer at Burke Mountain. "Sometimes she looks like she is going slower than everyone else because there is so little extra movement. You have to just look at her feet and ignore everything above that to see how fast she really is."

Shiffrin has worked to perfect that "quiet" style for nearly a decade. She studies video, exhaustively, especially tapes of former Croatian champion Janica Kostelic, who won six Olympic medals, four of them gold, with a dance-down-the-mountain style that still wins praise from skiing aesthetes.

"No matter what came up she just absorbed it with her legs," Shiffrin said of Kostelic. "She was always charging but in control. I admire that because so many skiers now look like they are going to die at any moment."

For most skiers, the 60-turn slalom race is a fight against the gates. For them, the gates stand in the way of the straightest possible line down the mountain. Because Shiffrin is so rarely off-balance, she experiences the gates as an opportunity to gain more energy and speed out of the turn as she throws her weight over her toes, keeps her skis close together and tilts them frighteningly high on their edges. "I'm trying to take the line that helps me use my skis best," she says.

The approach allows Shiffrin to feel like every run is just another dance through the gates under the lights in Vermont. Races aren't fights against the mountain but journeys back into a comfort zone established through thousands of extra hours on the snow.

That approach can help overcome jitters of the sort that struck her between two runs at February's World Championship. To combat the nerves that day, she took a free run with U.S. women's team coach Roland Pfeifer, who encouraged her to trust her instincts and her legs.

"He was like, 'Look, you are a skier,'" Shiffrin recalled Pfeifer telling her. "'You know how to ski. You do this every day so you don't need to be worried. You just need to remember that.'"

Write to Matthew Futterman at matthew.futterman@wsj.com

Corrections & Amplifications
Burke Mountain Academy is in Vermont. A previous version of this article said it was located in New Hampshire.