Knees clicking

My knees feel somewhat stranger over time as I progress over one leg squat progressions. I go fairly slow, I start about a year ago just with regular bodyweight squats, now I do a sort of half pistol squat. Now I've never outright had pain in my knees, or even discomfort really, it just feels sort of strange, as if there is a bubble of air in the joint or something putting pressure on things, and usually by knee will crack, as if one were cracking their knuckles, when I have this feeling in the knee.

 

What I want to know is if this a bad sign of something. I do not want something to happen in my knees. Again, no pain or discomfort, but I am so ignorant about these topics I'd though I might as well ask.

 

I am 18 years old and have never had an injury on my joints before, and I am 5'7 about 135 pounds for reference.

I know what you are talking about.  From about 15 to 21 or so, I felt that slight sensation of pressure in my knees as well.  It never hurt, never interfered with my training or any activities, but it felt vaguely unsettling.  Knees are important, and I trained martial arts heavily at the time, which really needs knees to be effective.

 

This feeling went away by itself.  I had forgotten about it until I read this topic, actually.  I went from 5'6 to 6'2 during those teenage years, and I figured that growth spurt played a part.  That said, you likely did not grow as fast as I did, so maybe that isn't it at all.

 

I've remained active and kicking my entire life, and I've never had any knee troubles.  I don't think there's any worry here, but maybe someone with more knowledge can step in.

thanks for the reply

This is what I've read: When you bend your knee under load, the joint capsule expands, decreasing the pressure within the joint. When the pressure becomes low enough, air bubbles will form spontaneously in the synovial fluid, making a loud pop or crack. The bubble will soon dissolve again. All in all, if there's no pain, don't worry about it.