couldn't even begin to tell you other than what you are proposing could be insanely hard and dangerous to the heart....
Many martial arts experts have trying to increase their speed and hardness at the expense of their circulatory and nervous system only to break it down or at worse die over such practice......
thx for the reply. i know its quite insane. i wasnt proposing anything but instead i would like i gain any medical information so that i can have a scientific answer to what is happening to the body of the martial artist. this is because i have seen a few people from a martial art called "silat" that can block with their body from being pierce or at least sustain only a minor injury. any journal or article would be helpful.
since the genitals and sexual organs are proofs that high blood flow can harden those area, i thought why not the whole body.
The rest of the body is not designed to be changed in such a manner as you suggested with sexual organs.
Closest to that is the pump a bodybuilder gets from lifting but that requires a combination of large muscle mass but very low body fat and in particular low subcontanous (skin) fat. Such hardness is only temporary and if experienced to often for too long is very dangerous to blood pressure and the heart over time.
However that kind of pump I doubt would be of any value in martial arts....not only is it not hard enough to meet the tasks you have mentioned, but that kind of pump limits the flexiblity and range of motion while the muscle is engorged with blood to some degree.