I'm 15 and I've notcied that when I eat my jaw sometimes cracks into place, when I do something with my shoulder that crakcs, and sometimes just when I extend my leg my knee cracks as well. Sometimes it even happens to my ankles. My shoulder is apparantly (according to a doctor) double jointed so that shouldn't be too bad. But at this age is it good for joints to crack like that? Is it just caused by growing bones and development?

i dunno but im 16 and i crack all the time i guess it just means you will get erthritis when your older ...depending on the type of crack..

so would swimming reduce the damage done on joints seeing as there is no impact?

As for my shoulder, apparantly I'm double jointed there. I'm still not convinced it does nothing too them though..

my knees crack all the time

first of all....

there is NO SUCH THING as being double jointed lol. and the fact that a docter said so is ALARMING! :P it might be that your shoulder is hypermobile ..meaning it has a bigger ROM (Range Of Motion) then normal. thus the cracking could be made by tendons reshifting from place during a movement.

same goes for the knee.. tendons that role of structures sometimes can make that noise. also it could be that you have sat for a while with your knees bent and thus the cartilage (sp?) takes on the shape of the space inside of the knee (cartilage is kind of soft so it can fit the joint good.) when you extend your knee.. the cartilage is still shaped as if the knee is in a bent position and that's what makes the "click" in your knee.

ankles: you have a lot of tendons going over the ankle so it wont come as a surprise that also tendons make those noises. it can also be that the joints in the foot are a lil less stable and thus making that noise (see my cartilage story above :P)

I don't think my shoulder has a larger ROM but I'm not sure.

So if its cartillage making the crack it won't lead to joint problems?

it could eventually. i think the best thing to do would train stability of these joints.

how do you do that?

I agree with Physio.

Also, the popping sound you hear when you intentionally crack your fingers, for instance, is the result of fluid moving from one side of the joint to the other. The same thing can happen in most joints in your body.

The popping sound can be annoying, and even a little embarresing in an otherwise quiet room, but its just something you have to deal with.