its a wonderfull thing called "slow-twitch muscle groups"
basically a avareage person has about 45% slow-twitch and 55% fast twitch muscles,
Slow twitch fibres are amazing at doing endurance exersicing, usually A well trained slow twich muscle can perform a contraction for easily 2 to 8 hours straight.
Fast twitch are great at doing fast actions, they have giant stores of glucose ready to be broken down quickly to get energy, Although fast twitch fibres are divided into two types, Type 1 and type 2.
Type 1 fast Twitch fibres can "transform" into slow twitch,
Type 2 arwee static and will always be.
So a crazy endurance runner will have nearly 70-80% slow twitch fibres within the muuscle system, this means they can do push-ups all day long, give them water and a big breakfast and you know who's coming in first place.
As to how to train your body to do this, I beleive takes a olympic coach. otherwise were all pretty much the same.
This post has been edited by Eskimo: 03 May 2010 - 06:57 PM