cool, you've actually seen some of the show! no, you become super sayan by getting really motivated to win, and by forcing that motivation through your body and using it as energy (or something like that). of course, people can't really become supersayans (especiaally since sayans don't exist), but being motivated, and forcing your mind to believe you can become super sayan is almost as good. i don't know for sure (then again i don't know any of this for sure ), but i think your subconscious mind has the ability to regulate blood and horomone flow (specifically adrenalin) to certain parts of the body. this would give you a burst of energy, which, when combined with motivation, can allow you to do things beyond your normal limits.

Hehe, dbz...i am so sick of that show now though, seeing as my brother and dad are obsessed with it.

 

Well, I bet once we fully understand how the brain works and all that (yeah, not for a long while I assume), then we'll be able to monitor all the chemical reactions and electro thingys going on, and right a program to read them, and show things up on the screen, perhaps reading our minds.