Oct. 18, 2008 -- "Mush!" is a command rarely heard south of the Canadian border, but for some up in Alaska, dog sledding is a way of life.
Martin Buser knows the life better than almost anyone. He's been competing in Alaska's famous Iditarod for more than 20 years. He's even won the race four times.
"I am the guy who know about 500 dogs by name and about ten people," Buser joked with "Good Morning America's" Kate Snow. "Being out with your best friends, with your canine athletes, if that's not what makes you drive -- if you only like the race, exposure and the little bit of fame -- you are doing it for the wrong motivation."
Buser has become famous. He makes his living off big sponsors, much like NASCAR racers. But Buser said that the race is only a very small part of an entire life that revolves around his canine friends.
"This Iditarod is not a sporting event that takes me 8 days, 22 hours, 46 minutes and 2 seconds -- but who's counting?" he said. "It really takes me 365; all year long to run that race.
Rookie Karin Hendrickson is just learning how time-consuming training for the big event can be and the financial toll it takes. The general rule is that one dog will cost about $1,000 per year in upkeep. Hendrickson estimated that she'll spend about $30,000 to run her first Iditarod.
If she finishes, she'll get $1,000 -- not even enough to pay for the booties her dogs wear in training. But for Hendrickson, the lifestyle is not now, nor ever was, about the money.
Just six years ago, Hendrickson was in California, living a more average life.
"I quit a pretty good career. I sold a house. I sold almost everything I own and moved up here," she said. "I worked for room and board to learn how to run dogs."
She says her friends still think she's crazy, but that is OK with her.
"There is a bond with the dogs," she said. "The places that you go and what you see and just the whole, when you really challenge yourself like mountain climbing or something like that, just to see if you can do it."