Sled dog racing (sometimes termed dog sled racing) is a winter dog sport most popular in the Arctic regions of the United States, Canada, Russia, and some European countries. It involves the timed competition of teams ofsleddogs that pull a sled with the dog driver or musher standing on the runners. The team completing the marked course in the least time is judged the winner.
Sled dogs, known also as sleighman dogs, sledge dogs, or sleddogs, are a highly trained dog type that are used to pull a dog sled, a wheel-less vehicle on runners, over snow or ice, by means of harnesses and lines.
Reference: Wikipedia Sled Dog Racing