I decide that the puppy needs muscle tone and should learn to navigate stairs. I put him a couple of steps down from the top and stand below him. Rippy waits at the top, to tempt him to climb. He promptly does a nose dive and tries to roll down the steps. I catch him and put him back. He sits there. He is stumped. Finally he turns around and tries to climb, but his hindquarters do not have the strength to boost him up even one step. I carry him up to the top, so he can climb up one step, and then I hold one of his back feet up a little bit. He pushes off and manages to scramble up, but it takes all his strength to do so.