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  • Recognize this sound? If you pop or crack your joints, you probably do. What happens

  • to our joints when we crack them? And is it bad for you? Synovial fluid is this lubricant-like

  • substance that's found in between your joints. It kind of looks like an egg yolk. So when

  • you stretch out your joint, you are releasing gas, and that gas forms a bubble and it collapses

  • and pops. In order to crack the same knuckle again, you have to wait about 20 minutes for

  • the gas to return back to that fluid. So how is that different from a pop you hear when

  • you stand up quickly? The sound you're probably hearing then is the snapping sound tendons

  • make when they slide between muscles or over bones. When a joint moves, the tendon snaps quickly

  • over and it makes a popping sound. So is the knuckle cracking habit safe? Probably. Donald

  • Unger was sort of a self-described researcher who chose to pop the joints in one of his

  • hands for 60 years, but not the other one. And he wanted to find out if popping your

  • knuckles would actually give you arthritis. After 60 years of doing it, he found that

  • he didn't have any more arthritis in one hand than in the other. Most medical sources agree with his finding.

  • But there's still a chance it's not good for you. One 1990 study did find that cracking your knuckles over a long period

  • of time led to hand swelling and decreased grip strength, but there hasn't been any

  • follow-up research on that. So while cracking your knuckles might not be bad for you, there's

  • still no guarantee that your popping habit won't annoy the people around you.

Recognize this sound? If you pop or crack your joints, you probably do. What happens

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Here's what happens to your knuckles when you crack them

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    Chamber posted on 2015/03/24
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