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If it were me and i had hurt my shoulder i would shoot one arrow first thin in the morning at a close distance. I have heard of a lot of folks talk about the single cold shot is the best practice because it is likely the same kind of condition you will actually be shooting under. Good Luck!
My sessions I'm shooting probably close to 100 arrows, how many are you guys sending down range each time you get the bow out? That might make a difference too.