I'm 70 and about to be 71 next month, I am hoping to go somewhere sheep hunting next year. Probably Alaska, as every where else more expensive. One thing that occurs to me is, it would seem from reading some of the hunt reports, there's no need to bust ass to get to the animals. Take your time. Might be longer getting there, but probably not so hard on a person. If you're getting ragged, take a break. I don't see why it has to be a marathon. To me, part of the hunt, would be to enjoy the territory, and camp part of it. A lot of the hunt stories I have read, makes it look like everyone wants to do it in 3 days. Like I said, why not take some time, and don't make it unpleasant.
