When I first started practicing about 2 months ago I had no problem holding eagle for the entire time, but recently I’ve been having a lot of problems holding it the entire time. The quadriceps muscle of the bent standing leg just gets so tired, starts burning and I have to exit the pose early. I am thinking that this is just a problem that will work itself out and maybe my muscles are hurting because I am bending lower and lifting my upper body more (in other words, doing the pose more correctly), but I wanted advice as to what or if I am doing something wrong.