Type IIx<span> are best known as </span>fast-twitch muscle<span> fibers. These are the muscle fibers primarily responsible for fast, </span>explosive<span> movements like sprinting. However, they lack the endurance-boosting ability of </span>slow-twitch fibers<span> and can only be used for </span>short<span> periods of time</span>
3,827 according to the internet.
The seminal vesicle adds a sugary, rich, and nutritious fluid to sperm.
