Yes, but he is a soft modern man. A hard medieval warrior would not have an issue doing that with double or more the draw that our modern wimp used here.
A hard medieval warrior propably wasn't much stronger than average joes today...
Bow drawing is 40% technique, most people could draw a 60 pounder, but definently not shoot properly. With proper muscle groups trained and proper technique, 100 pound bow is no longer anything impossible to draw and aim, or rather relase intuitively as quickly as possible.
http://www.youtube.com/watch?v=UgyXYnfPFQc Look at the smoothness of the motion, it's using all the momentum possible and the string arm moves right after bow-holding arm is straight, theres also a twisting motion.
Also bow effectiveness is not about the poundage, its a combination of arrow weighth, throw (springiness of the bow) and force (pounds) a high pound, low throw bow should be used with heavy arrows for most energy to the arrow, a high throw low pound bow with light arrows. (The bow that horse archerer on the first page used looked like it could throw an arrow with lightspeed, just the sound *bink* QQ)