I have 5 bully's and I'm sure none of mine would be able to walk for 1 hour. They are way different than boxers, especially when it comes to activity and breathing. Your vet may be right. lots of them do have surgery . if he's got lots of phlegm carry a plastic lemon in case he chokes on his own thick foam. squirt the lemon juice in his throat to open the airways of white foam.