The Type of Muscle Fiber That is Most Resistant to Fatigue

Question

The type of muscle fiber that is most resistant to fatigue is the ________ fiber.
A) fast
B) slow
C) intermediate
D) anaerobic
E) high-density

Accepted Answer

Slow-twitch or type I muscle fibers are most resistant to fatigue due to their reliance on oxidative metabolism and high concentration of mitochondria. They are capable of sustaining submaximal contractions for long periods of time, making them well-suited for endurance activities. Fast-twitch or type II muscle fibers, on the other hand, rely on anaerobic metabolism and fatigue more quickly, making them better suited for high-intensity activities but not endurance. Intermediate fibers have properties of both slow-twitch and fast-twitch fibers. Anaerobic and high-density fibers are not recognized classifications of muscle fibers.