[Sharing Lights]

Question: What's really happening when you "crack" your knuckles or feet?


Rarely, you push the joint back into or out of its normal position.

Usually this happens:

When you stretch or pull your finger and hear the popping noise, you are causing the bones to pull apart.
Vacuum (not real one of course) effect is created in the space enlarged.
A difference in pressure inside and outside of joints is increased.

On one hand, pressure is reduced on the synovial fluid and bubbles quickly expand and then burst - which is why you get that noise.

On the other hand, toxins, that accumulate in your body, emit by-product gases which, once, under pressure of a physical motion (as when you crack bones/joints) come out under that pressure and make the noise.

Look at it this way: sometimes, you pass gas.
Well, actually, sometimes - you don't...is more accurate (:

This “cracking” of joints is the same, only inside, as the gas can’t come out through any openings, when it is around joints.
Then, it is released inside your body.


Joints are the meeting points of two separate bones which are held together by connecting tissues and ligaments.

A thick, clear lubricant (made mostly of carbon dioxide and some nitrogen) called synovial fluid is found between the bones.