Watching this show called Sports Science. Some 50 yr old karate dude is letting American Gladiator Justice kick him in the nads without protection. Kick measures at 1100 lbs of force. Trained for 5 yrs - thousands of kicks to the nuts, only 10% of the pain chemical (Substance P) makes it to his brain. No pain. Testicles toughen. Lots of microfractures to pelvis make pelvic bones rock hard as they heal.
Something called combat ki.
More like something called fucking stupid...