The Dog Powered Scooter is a wonderful tool to help you focus your dogs energy, and to enjoy the new sport of Urban Dog Mushing. You can easily steer the dog, and all the dog needs to do is go forward. Initial resistance to get the scooter going is the only real strain on the dog, once the scooter is rolling the actual pulling load is minimal and of course the rider has the option of relieving the dog of all the load by kicking.
Source: The Dog Powered Scooter