Avi broke his ankle skiing. At first, he felt a sharp and intense pain. The next day, the sharp pain was gone, but his ankle throbbed almost all the time. The sharp, immediate pain was due to ; the later, throbbing pain was due to .

fast fibers; slow fibers

Explanation:

Avi broke his ankle skiing. At first, he felt a sharp and intense pain. The next day, the sharp pain was gone, but his ankle throbbed almost all the time. The sharp, immediate pain was due to fast fibers; the later, throbbing pain was due to slow fibers.

There are two general types of skeletal muscle fibers: slow-twitch (type I) and fast-twitch (type II). Slow-twitch muscles help enable long-endurance feats such as distance running, rthereby causing pain to linger for a while, while fast-twitch muscles fatigue faster but are used in powerful bursts of movements like sprinting making pain fast and short in terms of length

it all depends on how long the hours are. i think they wouldn't approve of it. in my opinion.