I've heard that if you hear a cracking noise when you bend your knees, say going down to grab something, that apparently you were meant to be a runner, and a good one? The cracking noise is just a noise, there is no pain or discomfort... so is this true?

thats soo not true. if you hear a cracking noise period it means you are wearing out ur bones or joints thefore it cracks. u if feel or hear any kind of noise it shouldnt be good.

It is the same crack from when you crack your fingers.

that's not true
i crack my knee whenever i sit down
and i suck at running

Well it isn't really a "crack' but a click, and it doesn't hurt, so i wouldn't think it'll be wear and tear of the bones..

What`s bad about cracking your knuckles? my knees also crack when i bend to get something, but i do practice martial arts.

::EDIT::
I just did a little research on this and it seems like theirs no negative effects, but a lot of people speculate that when you crack your knuckles it releases hydrogen or helium into your bloodstream. Also a lot of people say that it gives you athritis, but it hasen`t been proven yet.

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ehh. pretty sure it has no correlation. but I do know what your talking about.
hmm. try running? (:

lol my knees crack heaps too
and im not that much of a great runner XD

I'm a runner (not exactly the best...) and my knees crack all the time. I went to a trainer at my school and she said that if I don't feel any pain, there's nothing wrong with it and it happens to a lot of people, runner or not. A lot of it is because the knee cap isn't smooth so it tends to crack a lot. She said to prevent it, just ice after practice.

I asked my school doctor and she said that it's nothing to worry about. Even her knees crack when she bend down to sit or something. I guess it doesn't have anything to do with how a good runner you are...

me too .. and I aint a good runner .. I tire easily
seriously everytime I bend down .. it makes that *click* sound

i have a cracking noise in my knee, it just means you have to stretch you leg out more.