Until it starts to harden, slowing down the pace
The muscle inside your arm is makin' your joints ache

from Kendrick Lamar – Compton Chemistry Lyrics on Rap Genius

Meaning

Your muscles are beginning to ache because of the rotation but Kendrick already knows that you have never done this before because your raps say you are a pro right??

To help improve the meaning of these lyrics, visit “Compton Chemistry” by Kendrick Lamar Lyrics and leave a comment on the lyrics box