"Don't overdue it" is excellent advise, and I feel most archers could shoot more weight if they shot less often. Your muscles need to rest. Keep the heavy weight stuff focused on hunting, and practice accordingly (if that's your goal). Shoot one arrow at a time, making the most of your "one" shot, then retrieve. And remember, one good shot...execution... in practice is worth a hundred done as a chore. At nearly 51, I can still pickup my 70 and 80 pound longbows and shoot them well. My son Kory is probably your size and can shoot 80 pounds too, in fact he prefers it. We shoot primarily to hunt, though. If I shot lots of targets and 3-D stuff, just to shoot, I'd use a lighter bow.