When I still did karate we had these boards that were meant for kicking so they’d split. A training buddy and I were curious if they could be punched apart. I learned two things that day:
Yes
Knuckles don’t like that
While it wasn’t very painful at firat, beyond what I expected, it took me a few days to realize that the pain didn’t really go away. Then I happened to bump my fist/knuckles into this aluminium plate at work by accident, and it felt like my knuckles were hit with a hammer. And I didn’t even bump into it hard. This time the pain slowly went away over time until it one day was conpletely gone.
But to this day, 10 years later, f i accidentally bang my knuckles against something hard I notice very quickly that something isn’t quite how it should be.