>_> Jogging T___T
Ahh... the EIGs, well in its essence they're the ultimate form of taijutsu. Since our bodies are rather mysterious, we have such capability yet we only work at limits, this is to stop us from basically dying too soon. And the EIG are specific chakra points located throughout our anatomy that limit the flow of chakra circulating our body, and can trigger these limits to bypass, and as such allow our bodies to work at rates much exceeding the average persons capabilities (basically at our full potential), for an extended period of time. All of the gates are connected with each other as well as with our body, and the intensity of power you are able to use goes up step by step. However this does come with a price, once opened the EIGs don't last forever and soon enough you'll run out of energy, which is where the side effects kick in. As you increase the gates the severity of the side effects also increase. One that I can remember is when Gai opened the 7th gate whilst fighting Kisame, after the battle most of his muscles had been ripped to shreds which sent intense pain shivering down his body just by being touched. The 8th and last gate, gives the most tremendous power however imminent death awaits you if you were to ever open that gate. >_>
People with adept skills of the EIG are able to open more than one gate at once, as well as being able to close them before your body willingly gives up itself. In our RP, EIGM's are able to open up to 6th gate in one go and not feel any side effects afterwards, whilst simple EIG users are able to open up to the 3rd.
Also you get some pretty nifty physical effects that look quite cool >_>