A: We prefer a harness over a gentle leader. Gentle leaders wrap around the snout of a dog. Boxers already have a shorter snout, so gentle leaders arent the best fit. Q: Whats the best harness for running with my boxer? A: The Kurgo Air journey is one of the best Boxer harnesses you can buy, for running, walking or otherwise. Its the most expensive on our list, but its our top pick for any activity.