What physical condition do I need to be in?
Hunting can be an arduous undertaking. Therefore, I recommend you be in the best physical condition possible. Your chances of succeeding may depend on your conditioning. If your animal is on the move you may be required to cover ground quickly and for a long period in order to get a shot at him. You may have to spend the night out on the mountain, or walk through several miles of soggy tundra and (heaven forbid) alders. Good conditioning plays a big part in mental attitude. A fatigued hunter is more likely to turn back just short of getting his trophy. Just short of what you came up here to do.
I realize that busy schedules often preclude getting in shape. Most of my guides can walk the legs off a centipede and they would love for you to be able to match them, step for step, but if you can't they will adjust the pace of the hunt to suit you. Realistically though, better shape, better chance.