I’m a fast twitch monster and I’m finally growing since I started training with 3 or 4 reps instead of the good old 8-12. Does anyone also train this way and knows some other training methods which effectively hit the fast twitch fibers (to get some change)?
Can some one please elaborate more on fast twitch slow twitch? All I really know if different fibers respond differently to different rep ranges. Is that it? Also, has anyone tried muscle endurance training for mass. Not high reps, but short(er) rest periods. (say 1-1.30 min)[/quote]
There are 3 types of muscle fibers that compramise skeletal muscle:
Type Ia (slow-twitch oxidative) fibers: Fibers that undergo oxidative metabolism while working. These fibers are for a longer period of time, but provide very little power. These are used when you are running, walking, doing every normal things without really putting much strenuous effort. Cannot really be trained for size. Endurance training provides pretty good health benefits for the average person here.
Type IIa (fast-twitch oxidative) fibers: These also are able to provide some more power and strength, as well as more of a long term use. These are the middle ground between slow and fast twitch, having characteristics of both aerobic and anaerobic metabolism (producing energy with or without oxygen). Modest increase in size.
Type IIb (fast-twitch glycolytic) fibers: These fibers are the ones that we are working on when we are strength training. They have the greatest capacity for size and strength gains. They are able to provide high power, but for a short duration relative to the other fibers. T-Nation is obsessed with this one, and rightfully so.
Your body’s makeup of how much type of fiber you have is predominantly genetically determined. There’s a little biology lesson for ya. Helps me too, I just took a final for this stuff at school. But next time, google the damn thing =P