Yes, in reality the human body degrades very quickly in areas that cannot be strengthened. Anyone who fights professionally or even spars with trained peers with some regularity are going to end up with a raft of injuries and brain issues. It only takes one slip in a light sparring match to get damaged for life (elbows are a bitch).

We had a guy join our gym and end up posting a hand on the wall the first night during a drill. He was out for a month. I have done the same on the floor with permeant results.