It seems like everytime I do leg presses (on a non-reclined machine), my knees hurt afterwards. Maybe I'm just straining the muscles around my knees and not my knees themselves? I don't feel the same strain when I squat though... and I'm wondering if some leg press machines are notorious for putting more strain on the knees. I mean, whereas you can determine the motion of a squat on your own, you kind of have to go with the flow of a leg press machine (in other words, it seems like you have less control). Maybe I'm just doing them wrong altogether. By the way, I usually squat with 2-3 45's on each side and I will legpress with 5-6 45's on each side.