My knee warmers are too tight. I don't think they let the patella move normally. It gets worse when my muscles start to swell during an intense ride. Overall, they are the "right" size (bigger and they'd fall down), but they aren't really that ergonomically designed. I'm always tugging at them to try to get them looser over the patella. I got leg warmers from a different brand that are made much more contoured to the leg. I have no problems with those.