Slow-twitch muscle fibers
A) are the predominant type of muscle fibers in the upper limbs.
B) have a richer blood supply than fast twitch fibers, and contain myoglobin.
C) would be used for activities resulting in (or requiring) anaerobic respiration.
D) fatigue more easily than fast-twitch fibers.
E) have all of these characteristics.

Question

Quizplus · Accepted Answer

Slow-twitch muscle fibers have a higher concentration of myoglobin and rely on oxidative metabolism, which means they require a rich blood supply. They are utilized for endurance activities that require sustained activity, rather than short bursts of rapid movement, and do not fatigue as easily as fast-twitch fibers.

Slow-Twitch Muscle Fibers