I Siberian can do the Iditarod if it's in good condition and the musher knows how to watch his team, but this is true for any sled dog. I see no reason not to run a Sibe team in distance races, it's what they were created for. But the breeder, handler and musher need experience and knowledge of the breed. They would also need to understand that Alaskan Huskies, bred from Siberians and crossed with greyhounds, malamutes, and many other dogs are probably going to be faster because of this.
Also Pitts do weight pulling at a walk or trot over very short distances. We are talking pulling over a distance of feet, not miles here, huge difference. The neighbor's Pitt I mentioned is training for weight pulling. You would not want to make that dog run all day pulling weight, it would break down. The Pitt is a very strong dog, is game enough and loyal enough to try, but it would hurt itself in the process. The pitbull is not a sled dog and should never be considered as such. I have a dog that would do anything I asked, just to make me happy. But as his owner it's my job to protect him from doing things that could injure him. He is fast, lean, very agile, smart, but even though he can outrun my Siberians in a sprint, I would never race or sled him. He has way too much up and down bouncing when running and gets tired way before the Siberians because of all the energy he wastes. This is yet another consideration before buying sled dogs. Some people would run him in harness, I would not.
