I have one bad knee, but honestly, squatting deep actually helps it. Just have to find the right form to be able to do this comfortably. Everyone's hips are different, and effect this. For me, going with a slightly wide stance, toes out, allows me to go ass to grass all the time even though I have a bad knee, and even aids in stability.
I also use SlingShot neoprene knee sleeves (not wraps, as these can cause further damage). The knee sleeves act to heavily warm up the area. I never have pain while wearing them!
From bands and sleeves to heavy duty braces and supports, Rogue has the knee protection to help any weightlifter gear up for the next workout. Browse our selection here.
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But yes, it's a total myth that squatting deep is bad for your knees. It's definitely helped me.
Why Deep Squats Are The Best Squats
www.huffpost.com
Contrary to popular belief, squatting deep is not bad for the knees -- studies have found there is no difference between partial, parallel and deep squats in terms of the impact on the front knee joint. In fact, deep squats might actually increase knee stability.