After prolonged resistance training, which muscle fiber type tends to be recruited first?

After prolonged resistance training, which muscle fiber type tends to be recruited first?

• A. Slow-twitch first
• B. Fast-twitch first
• C. Only fast-twitch
• D. Intermediate fibers

Answer: (B)

Prolonged resistance work changes how the nervous system activates muscle fibers. Training enhances neural drive to the fast-twitch units, so they can be recruited more readily and at higher levels earlier in a sustained effort. Fast-twitch fibers generate more force and respond quickly, which helps maintain performance as fatigue sets in. While slower, more fatigue-resistant fibers still contribute, the need to sustain high force during a long set makes these fast-twitch units come into play sooner than before. So, in this trained context, fast-twitch fibers tend to be recruited first.

Prolonged resistance work changes how the nervous system activates muscle fibers. Training enhances neural drive to the fast-twitch units, so they can be recruited more readily and at higher levels earlier in a sustained effort. Fast-twitch fibers generate more force and respond quickly, which helps maintain performance as fatigue sets in. While slower, more fatigue-resistant fibers still contribute, the need to sustain high force during a long set makes these fast-twitch units come into play sooner than before. So, in this trained context, fast-twitch fibers tend to be recruited first.