Keep in mind that if you are shooting 50 or 60 lbs. that you may in a hunting situation be forced to hold your draw for more than a minute. I've held at full draw for what seemed like hours at the time but in reality was probably no more that a minute and a half.

At the end of my shooting session I like to draw my bow and hold it as long as possible. Usually be this time my mussels are a little tired so I can't hold real long but I do believe this helps to train for hunting situations.