Why is this...the top hurts sometimes but not like the rest....any ideas as to why and what I can do to help it out...The only thing I can think of is that when I was doing Lat pulldowns...there is a leg pad and I don't think I had my legs far enough under and my weight wa heavy (115) so I was putting pressure on the tops of my knee caps. But as soon as I do any treadmill the back of knee tightens....help 
