I had a question about this sort of thing. I'm only 19, but as a fitness enthusiast I'm still concerned about it.
When I do a lot of stretching, or exercises which involve a large range of motion, my joints (knuckles, knees, shoulders) sound like popcorn on the oven. I don't think that this is a healthy thing to be hearing; are there any specific exercises or practices I can do to help alleviate this?