They are ancient by their sports' standards, flipping and swooping and surviving bone-crunching falls in a world that worships the young.
Look at Jeff Ward, a SuperMoto rider at 43. Then there's Dave Mirra, a 30-year-old BMX biker who simply wants to pack his gear and go home at the end of a long day. Bob Burnquist has a 4-year-old daughter who was on a skateboard before she could walk.
Sure, the X Games (search) are marking their 10th year with the usual reckless mix of breathtaking speed and bravura-testing midair stunts. But now some of the event's biggest names are well outside the youth culture that defines action sports.
They've become elder statesmen in pursuits that deliver harsh bodily punishment for not-quite-complete twists and awkward landings.
Burnquist, Mirra and a handful of other stars have video games named for them, appear in TV milk ads and have written autobiographies. They are the mainstream, maturing faces of alternative sports.
"It's awesome," said longtime dirt bike rider Mike Metzger (search), who appeared in Mountain Dew commercials and lands a backflip in the movie "Charlie's Angels: Full Throttle." (search) "And it's totally ridiculous that I'm a well-known celebrity now because of all the coverage."
Organizers of the X Games, which began Thursday in the Los Angeles area, are banking on the star power of the sports' established athletes. (The games will be broadcast live on ESPN and ABC.)
For the first time, qualifying rounds have been eliminated. Instead, industry experts selected up to 10 people to compete in each of 17 finals-only events.
The oldest athlete is Ward. The youngest is a returning champion, 14-year-old skateboarder Ryan Sheckler (search), who is on his way to ninth grade in Orange County. Sheckler said "it's been a little weird" going head-to-head against competitors nearly twice his age.
"This is what it's been like forever. I've always skated against older people," he said.
Media exposure of aging stars like Tony Hawk (search) -- who is working as an announcer this year -- has helped legitimize action sports for parents and allowed children to develop skills more quickly, X Games general manager Chris Stiepock said.
"Now you've got less of a stigma" attached to alternative sports, he said. "The youngsters are coming up."
Pro skateboarder Andy MacDonald, 31, finds himself swooping past kids as young as 5 when he shows up to skate for fun at parks around the country.
"I'd be lying if I didn't say it makes me feel old," he said. "I wish I started that young because it seems like you're made out of rubber and the learning curve goes up faster."
Falls are frequent in action sports, at any age.
"The younger the body, the easier it is when you slam," said Burnquist, who has recovered from 25 broken bones. "When I get hurt, it's time to heal. It's just heal, heal, heal, and then it's time to get back on the board."
Skateboarder Danny Way, 30, returns to competition this year on a gigantic new ramp he helped develop after getting bored with conventional half-pipes.
"I'm feeling mentally 18, but my body feels 60," he said. "I'm not going to lie."
Mirra, who has hosted shows on MTV, feels distanced at times from the young bike riders at skate parks.
"My wants and needs have changed a little bit in terms of living to ride a bike every day," he said. "It's more put your bike in the car, go to the skate park, ride and go home."
Action sports stars make most of their money from sponsorships, appearance fees and videos. Several have launched businesses, ranging from Burnquist's organic fruit and vegetable farm to Way's DC Shoes. Surfer Kelly Slater (search) is starting a weekly satellite radio show.
"Thank God for the business thing," Way said. "Right now it's taking a lot of pressure off my skate career."
MacDonald lends his name to mass-marketed skateboards and gear, eyeing the time when he'll no longer be admired by the young.
"Pretty soon you won't be marketable any more," he said. "Because kids don't want to see their fathers skating."