Caleb Moore’s condition worsened after he was taken to a hospital following his crash. (Christian Murdock / AP)

Editor’s note: Caleb Moore died today of his injuries. Read the story here.

Snowmobiler Caleb Moore remains in critical condition in the intensive-care unit of a Colorado hospital after sustaining injuries in a crash that has raised new questions about the dangers of extreme competition and an athlete’s quest to find a delicate balance of risk and jaw-dropping performance.

“Caleb is in critical condition and is being closely monitored,” family spokesperson Chelsea Lawson said Tuesday. “The Moores want to express their gratitude to all of Caleb’s fans, friends and family for their strong support and ask for continued prayers in the coming days. The family will not be making any other public statements for the time being. Thank you for respecting the family’s privacy during this difficult time.”

Moore’s grandfather, Charles, told The Denver Post that “the prognosis is not good at all. It’s almost certain he’s not going to make it.”

Moore, 25, caught the lip of a rise that was a landing area with the skis of his snowmobile as he was trying to complete a flip. He flew over the handlebars and the 450-pound snowmobile rolled over him as he lay in the snow. He was taken to an Aspen hospital with a concussion and was airlifted to a Grand Junction hospital when bleeding around his heart was discovered. He underwent surgery Friday morning and, on Sunday, a family spokeswoman said the cardiac contusion had led to “a secondary complication involving his brain.”

Moore’s crash comes a little over a year after Sarah Burke, a Canadian freestyle pioneer, died nine days after suffering irreversible brain damage while training in Park City, Utah. Burke was one of the leaders in the movement to include slope-style and half-pipe skiing at the 2014 Winter Games in Sochi, Russia, and her accident rocked the X Games.

In the 17th edition of the Winter X Games at Buttermilk in Aspen, there were plenty of crashes over the weekend but few serious injuries in a sport in which the pressure to do increasingly difficult maneuvers is intense. Rose Battersby, a skier from New Zealand, fractured her back when her jump came up short and said Monday night  on Facebook: “My spine has now been but back together and I am pleased to say that my toes can wiggle!!!”

Moore’s brother, Colten, suffered a separated pelvis and Jackson Strong’s snowmobile flew into the crowd when its rider fell off on a jump that went amiss.

Caleb Moore’s injury left competitors wondering just how much longer they can continue to raise the bar on stunts…only to raise it again. “When is enough enough?” professional snowmobiler Paul Thacker said he and his competitors were asking themselves (via the Denver Post).

A 2010 training accident left Thacker, 36, a paraplegic and he was competing in Aspen over the weekend in adaptive snowmobile racing.

“I’m always asked the question, ‘Where’s the ceiling?’ And every year we are like, ‘It’s not going to get any gnarlier,’ ” Thacker told the Denver Post. “They are never going to do a double back. They are never going to do a frontflip. But then it happens.

“It’s kind of like you tell me I can’t do something and I’ll show you how I can. It’s how we are wired.”

Kaya Turski admits there’s a fine line when it comes to balancing risk and pushing the envelope.  (Michael Ciaglo / AP)

ESPN X Games officials say that safety has always been a priority and there has never been a fatality. “We’ve worked closely on safety issues with athletes, course designers and other experts for each of the 18 years of X Games,” officials said in a statement. “Still, when the world’s best compete at the highest level in any sport, risks remain. Caleb is a four-time X Games medalist who fell short on his rotation on a move he has landed several times previously.”

Athletes continue to balance risk with the desire to live at the edge of what is humanly possible.

“As pro athletes doing what we do, I think we all accept and understand that these are inherent risks in the sport, and I wouldn’t do it if I didn’t believe in myself,” Kaya Turski, a three-time X Games gold medalist in slopestyle, said in a Denver Post interview. “Still, it is a fine line, and I’ve crossed that line a few times.”

And, if an athlete ends up on the wrong side of that fine line?

“We are modern-day explorers,” Jimmy Fejes, one of the first to backflip a snowmobile, told the Denver Post. “There are no new places in the world to see and discover, so you have to try to create new things. That’s who everybody is.”

The X Games snowmobile freestyle course “could not have been any safer,” Fejes pointed out, because ramp positions, landing ramp angles and distances have now been calculated to minimize risk. Except there’s always the possibility of human error, which is what, Fejes said, caused Moore to crash when he under-rotated on his backflip

“Everything was perfect.” Fejes said. “Caleb has thrown that trick hundreds of times. It was just a very fluke accident.”

Moore’s family has set up a website to raise money to pay for his medical bills.

“The world knows Caleb as a brilliant freestyle rider, but his family and friends know him as a fun-loving and deeply loyal person,” the Give Forward page reads. “This is our chance to show Caleb and his family how much they mean to us all.”

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