HELP!! My knees and elbows are popping like crazy. My knees really hurt bad, and the popping has gotten worse. Since I started working my legs more (deep hack squats, deep squats, heavy and deep leg presses), my legs have grown, but at a price. When I touch the top edge of my knee caps they hurt; my knees hurt when I sit. I have to keep my legs stretched out to avoid the pain. My elbows pop when I flex, or when I am doing tripcep exercises.