Well, I know with Finn, I'd have to walk him for four hours to wear him out. And, maybe one day I'll be in good enough shape to make it that far. But, for Finn, I always tire before he does. Unless it's swimming. I can kayak and he swims beside me. That has been the only way that I can wear him out without help from others. He played ball one day at the dog park for a good five hours, I had so much help, though, from other people, throwing the ball. I plan to get one of those bike attachments for sure. I'd do the car thing too if I wasn't afraid something bad would happen. I'd walk him myself for a bit, but, that would certainly help after an hour or so. Good luck!