The floor I danced on last night was the stickiest dance floor I've ever danced on; it was as if it were coated with epoxy. The shoes I wore weren't sueded on the bottom, either, which would have helped. And this being a big dance weekend, I had partners who really put me through the paces. Yet after a few hours of dancing, I had no knee pain. None.
I attribute this to a few things. First, after I started a low-carb diet, a lot of my joint pain disappeared: I believe the carbs were inflammatory; my doctor thinks I may have had a wheat allergy. Second, I've been doing a new strength training program (Slow Burn) that has strengthened my legs. Having lifted weights for six years and danced for eight, I thought I had strong legs. But the single-leg, slow-motion doorknob squats have strengthened them further without hurting my knees at all.
I noticed something similar a year or two ago when I started doing ab exercises with my neck lifted: much of my neck pain disappeared. I believe the isometric neck exercise strengthened my neck muscles.
A lot of the popping and cracking of my joints has disappeared, too. Nobody knows what causes popping, and I never found it painful, but it's startled a few of my dance partners who felt my bones suddenly shift.