system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can martial arts specialists punch through rock or wood?

How can some people punch through bricks or wood boards without getting hurt. What's the scientific explanation behind this?
gpt
The trick is you have to break it or you're really going to hurt yourself.

Let's say that you have a block of wood. That block of wood will break if you apply enough force to it. Let's say you need to apply 100 pounds of force to break it. You could rest 100 pounds of weights on it or you could hit it with your 1 pound fist going really fast.

But, let's say you only hit it with 90 pounds of force. You'll probably bend the wood some but the majority of the energy will bounce back into your hand, possibly causing injury. If you hit it with 100 pounds of force or more then the energy will be used to break the fibers of the wood and it won't rebound into your fist.