Which fiber type is a liability in events that require prolo

Which fiber type is a liability in events that require prolonged duration of muscular power? Explain

Solution

Muscle fibers are of mainly three types, ie, type I, IIA, and IIX fibers. Type 1 are regarded as slow-twitch fibers which are helpful long duration contractile activities, i.e, those activities requiring prolonged endurance or muscular power for longer duration, like distance running. These are typically red fibers (blood-carrying myoglobin present), with adundant mitochonria for ATP generation.

However, type II and IIX fibers are fast-twitch muscle fibers, which are mostly useful in powerful bursts events such as sprinting. They could be reagrded as liability in the events that require prolonged duration of muscular power. These fibers are helpful for power athletes, as they facilitate short term anaerobic exercise. They are white fibers with high threshold and are activated only when needed, can generate greater force but causes early fatigue, because they either use oxygen to convert glycogen to ATP, as energy source or rely on ATP stored in the muscle cell.