How old does a sled dog have to be before it can pull a sled?

They start training at a very young age but they dog sled until they are about 10 years old.

with treats and what ever the dog likes. example: hook the dog up to the sled and use a ball (if it likes it , if not use treats) to lure it to pull.

The individual dogs and breeds are large and strong, and can endure many hours in harsh weather conditions. A team of just six to eight dogs can pull several hundred pounds on a snow sled.

it depends on how much the dogs weight

Well, it depends on the breed of the dog. Like the Saint Bernard ( don't get a Saint Bernard. I have one and she is vicious) and the Husky, they would go about 30 M.P.H. But im a kid. I'm just...