The one inch punch GIF

Damn son!

Apparently that guy went up to Bruce Lee afterwards and asked him to never try that again because of how much pain it caused.

Reminds me of Kill Bill. Badass.

Holy shit!
His chest fucking caved!!!

I've been practicing JKD and I can say for sure that you can definitely produce this much force in such a short punch. The movement through his whole body should be noted, as each flexing muscle is a contributing factor to his punch.