The thing that really gets praise is proving how tough you are-- that is, your ability to ignore your evolved safety signals.

I can't speak for everyone, but this is not the case in my experience. I used to attend my old university's boxing club and anyone caught ignoring his evolutionary safety signals would have been told to go home, safety was extremely important there, primarily because the university could potentially be legally liable for anything that went wrong.

There certainly was an element of machismo in being able to grit your teeth through the last fifteen minutes of an intense round of cardio, but it's about defying the voice in your head that tells you to give up, you're kidding yourself, you're too weak to be doing this, rather than defying the voice that tells you that you are seriously in danger of cardiac arrest if you don't stop skipping rope.

A large part of the experience is learning to separate those voices out, know which is which, and know what your real limits are, and what you are in fact capable of as opposed to what you think you're (in)capable of.