what kind of bow are you shooting?
i am shooting a pse nova @ 48#
with a biscuit rest. it isnt really you arm muscles that take the beating it is your back muscles, like i have a friend who probaly has more mucsles in his arms, but he cant pull my bow back, but i can, and he is a little twig, i actully meat on me, but if you can lower you poundage i would do it. it will help alot.