Went riding last weekend and almost dislocated my knee in a panic foot plant! What I didn't do was to stop after first 20 minutes and re-adjust my knee brace. The nylon velcro webbing gets looser with heat and sweat creating a poorly fitting brace that will not do it's job. Was lucky as I have no ACL ligament in that knee from my freestyle skiing past. So if you wear a knee brace because of a similar condition PLEASE stop once warmed up and maybe even more to monitor fit.