I was at the gym the other day doing leg presses, and one of the trainers came over while I was doing them and told me I was going too low and would hurt my knee. However, when I worked out for the past year with my team at school, we went past that, and we've got a guy overlooking the room who is jacked and seemed to know pretty much all there was to know about lifting. So, I'm taking it to you ATers. Which is right? All the way down, or stop at a 90 degree angle?
Animated gif of what I was first taught
Animated gif of what I was first taught