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To many, it is insane for an athlete to do a backflip while driving a 450-pound snowmobile. But for CalebMoore and other freestyle snowmobilers, it's just another trick. Moore performed his failed stunt during theWinter X Games on January 24, 2013 and died a week later. The stunt was difficult but apparently doable. He haddone it many times before. So what do we make of this?

By definition, “extreme" sports are difficult or dangerous, performed in a hazardous environment. The veryessence of these sports is to push things as far as possible and then try to take them farther. Part of their massiveappeal is that these sports constantly walk on the thin edge between brilliance and disaster. The fans, corporatesponsors, and especially the athletes know this. It's just a part of what they do, but the death of a 25-year-old isn'tsupposed to be the result of a sporting contest for our entertainment.

In the 18-year history of ESPN's X Games, Moore was the first to die in competition. But why is my initialreaction, "Geez, I can't believe there have not been more.” I mean, really, who thinks someone can surviveattempting a backflip on a 450-pound snowmobile? But one person does it, then another and the one after thatuntil it ultimately becomes a routine trick. And then it is time to develop the next one that will be even moreinsane. I am not saying that the people involved with extreme sports trying to perform some seemly impossiblestunt are not concerned with the utmost in safety standards. Maybe it's because these extreme sports haven't yetreached their final frontier of possibility. However, I can't help wondering if they ever set the limit: How farshould they push the envelope?

So I say it's insane when I see some teenager shoot 30 feet into the air out of a halfpipe to do twists and flipson a skateboard or a snowboard, or when I see some free climber risk a fatal drop just to reach a summit. Andwhen they have turned what I had previously considered the impossible into the probable, I ask myself: “Whatwill they try next? And how far will they go before somebody kills himself?”