Hey Robert.
Basically, Type 1 (slow oxidative fibres, which account for approx. 50% of total muscle fibres) contract slowly (relatively very few fibres are stimulated at any one time, making them virtually fatigue resistent. These is the muscle type used by say marathon runners), are aerobic (use oxygen/ require you to "breath" during length of activity so as to create energy), have relatively low glycogen stores (as they generate a low amount of force at any one time during stimulation).
Type 2a (fast oxidative fibres, which account for approx. 35% of total muscle fibres) contract intermediately (faster/ more fibres contracting at one time compared to type 1s, but lesser compared to type 2bs, making them moderately fatgiue resistent. These is the muscle type used by you Steven, the armwrestler), are aerobic, and have moderate glycogen stores.
Type 2b (fast glycolytic fibres, which account for apprx. 15% of total muscle fibres) contract fast (a very large force generated at any given time as the majority of these fibres are being stimulated <fired by the nerve's axons> at one time, they fatigue very quickly, and are used in actions such as hitting or throwing a baseball, throwing a javelin/ shotputt etc.) are anaerobic (breakdown glucose without the presense of oxygen), and have high glycogen stores.
People are born with a pre-disposed number of the two different fibres. Some people may have 60% type 1 (born to be marathon runners), and some may have 60% type 2 (born powerlfters and weightlifters). You cannot change the ratio between type 1 and 2, but with proper training, you can change your type 2a and type 2b ratio. In some elite athletes, there are no type 2b muscle fibres.
Bah, this doesn't belong in Chat, but watcha gonna do
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