Go lower. Get a 40-50. When you are stiff and cold, you need to be able to draw the bow with good form and make a good shot. If you can't comfortably draw and hold the bow at full draw, you won't be able to hit anything anyway, so all your extra poundage will just drive the arrow deeper in the dirt. You will have the option of getting a higher poundage bow when those muscles are stronger down the road, but by then you will probably realize you don't need it. I cringe when I see hunting shows with footage of these guys drawing bows and they have to contort themselves to get to full draw, it should be smooth and relatively easy, find the bow that lets you do it that way. Form and shot placement are key.
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