As I stated in the other forum
Just train your body what you want it to do... If you're a sprinter, you shouldn't train your body like a
body builder or hockey player (yes, some exercises overlap)...
For the most part
muscle fiber types is mainly about genetics (like jay` said)... I think it was the Russians that use to "muscle fiber type" their athletes and tell them what sport their body is good for, but as you can tell it doesn't work so well

... Because they had the body for that activity, but success depends many factors such as training, skill, and dedication.
(But to be technical, there are actually 3 types of muscle fibers....
Slow Oxidative, Fast Oxidative Glycolytic, and Fast Glycolytic.)