I'm not even sure that would be something I would even be interested in unless I was going to compete professionally. I know within 10-15 years this may not even be a possibility for me even if I want to train like that. The good news is that the majority of the people on this planet don't train at the level of professional athletes, so I'm not likely to get into a fight with someone in that level of condition. Even if I were to be in conflict with one, I wouldn't try to fight someone that seems to be in better condition to fight unless there was no other choice.
If I had an argument with a young Mike Tyson or Roy Jones Jr, then I would know from the beginning of the argument that I'm not fighting either one of them. They could punk me all they want because a fight wouldn't be in my best interest. Now if they attacked me then I would have to defend myself to the best of my ability, but I know it's going to be one of those fights that you physically lose, but respectfully win because you didn't back down. It would still be a beating for me. But the world isn't made of professional fighters and the chances of me fighting someone who isn't in good shape for fighting is higher than me fighting a professional fighter.