Harry, you do better than I'd guess 98.5% of people your age.
I'm not nearly as old as you (!!) but I can feel a difference with each year. That accelerates the older you get (as you're no doubt well aware), but it also applies to 30- and 40-something guys.
The fact is, as you age you lose a lot of things that help with backpack hunting and everyday life. Strength, muscle mass, muscle tone, balance, flexibility, cardio capacity and so on and so forth. It also becomes much easier to "tweak" something if you lift too much, without warming up, or with bad technique.
Working on all the stuff that declines with age will surely make you a better hunter, and that's just the icing on the cake.
