MEDICAL PHYSIOLOGY

Detailed explanation-1: -These fast-twitch fibers use anaerobic metabolism to create energy and are the “classic” fast-twitch muscle fibers that excel at producing quick, powerful bursts of speed.

Detailed explanation-2: -Fast oxidative muscles, also known as type II-A fast twitch also use aerobic respiration and contain a high amount of oxygen, myoglobin and mitochondria, but they break down ATP quickly and therefore contract quickly.

Detailed explanation-3: -Fast-Twitch Muscles Fast-twitch fibers contract quickly and provide strength and speed, though they also fatigue more quickly. Sprinters require short but intense bursts of energy and therefore need more fast-twitch muscle fibers. Fast-twitch muscle fibers rely on ATP and glycogen as their main energy source.

Detailed explanation-4: -Type IIx fibers, or fast glycolytic fibers, possess the fastest twitch speeds but are highly fatigable [1].

Detailed explanation-5: -FG fibers are used to produce rapid, forceful contractions to make quick, powerful movements. These fibers fatigue quickly, permitting them to only be used for short periods. Note: Type IIb muscle fibers are actually type IIx fibers.