My dogs try to bite me, and get violent with each other when I go sledding?

My dogs are about 8 years old, are brother and sister of rottweilers, and would never hurt a fly. When I go outside sled (I have a hill road) around my sled, and every time I push myself or move an inch, which will begin to fight (actually not violently) and growling at each other. Then, when I go down the hill, it will be biting my jacket, my leg, and cut boots. What is happening here and why are they doing this?

Well, remember that you are standing, you are in the floor magically move away from them and going faster than usual. Could be a case of "Catch Me, or persecute me or they could figure are in danger, or you're doing something completely out of character and different that they get so excited they do not know how to make your start grabbing and others.

The New Swallow Cliff Sledding Hill