Discuss the two types of muscle fibers in the human body

Question

What will be an ideal response?

Answer 1

The human body has two basic types of muscle fibers: (a) slow-twitch or red fibers and (b) fast-twitch or white fibers. Slow-twitch fibers have a greater capacity for aerobic work. Fast-twitch fibers have a greater capacity for anaerobic work and produce more overall force. The latter are important for quick and powerful movements commonly used in strength-training activities. The proportion of slow- and fast-twitch fibers is determined genetically and consequently varies from one person to another. Nevertheless, training increases the functional capacity of both types of fiber, and more specifically, strength training increases their ability to exert force. During muscular contraction, slow-twitch fibers always are recruited first. As the force and speed of muscle contraction increase, the relative importance of the fast-twitch fibers increases. To activate the fast-twitch fibers, an activity must be intense and powerful.