MESA, Colo. Sunday was the second and final day of the Grand Mesa Challenge Summit Sled Dog Races. Competitors and their canines trekked through the high altitudes, racing for the fastest times.

Thirty-six teams competed, some working to get a spot at the world championships in Alaska. The races were all about speed and endurance, which the dogs have.

These dogs are not only mans best friend, they're also loyal teammates through the odds.

John Perry, a professional dog sled racer and retired teacher, said, "If you work with dogs you have to think like a dog. It becomes a connection that you can't get with a human being."

Perry, a six-time international gold medalist says there's no better feeling than cutting through the wind on a sled.

"The dogs are pumped up, and when they start yelling, screaming, hollering, boy that rubs off on me and my adrenaline's coming out my ears," said Perry.

Sam Christman, a dog musher of four years, said, "Pulling across the finish line every time is a really great memory. It's just a testament to how great these animals are."

The Grand Mesa Summit Challenge featured some of the worlds fiercest canines.

Teresa Petterson, a competitor and veterinarian, said, "I have a six- and-a-half-year-old Greater Swiss Mountain Dog named Bridger. He holds the record for the Swiss Mountain Dogs, he's pulled 4,865 pounds."

Steve Bethka, race organizer, said, "There's the world championships, sprint dog championships, in Fairbanks, Alaska this year, and some of them are actually trying to make the team through this race."

For Perry, winning the gold medal in Alaska would be the ultimate end to his career.

"That's going to be it for me, so, I can't even tell you," he said.

Whether or not they achieve their goals, it's all about the dogs at the end of the day.

"Some people think it's cruel to make them work this hard, but a dog wouldn't do it unless they loved what they're doing," said Petterson.

Perry said, "I think it's so phenomenal that dogs have that connection with people, and just to be able to think they're even able to do that, it makes us a little bit closer."

Because at the end of the day they are more than just teammates, they're family.