I'm 58+, no weight or real health issues...except for arthritis in my lower back, along with spinal stenosis. I'm also allergic to bee stings. Since I have consistent level 3 to level 4 pain in my lower back, I was concerned about my endurance for my outfitted 2014 BC, Canada / Purcell Wilderness elk trip. I went to my Dr. who referred me our a local pain clinic, and I had injections in my lower back, two weeks before the trip. GOOD THING I GOT THE INJECTIONS ! 25 miles one way on horse back, interspersed with more riding + walking 35 miles during that hunt + the 25 mile ride out...never felt a thing, and the injection benefits lasted another 4 months. Things I learned: Be prepared for the constant wash board type of repetitive jolts to your back that occur when a horse is trotting. Be prepared for your horse to bolt. When horses get stung by ground hornets ( there were 7 nests we came across along the trail, on the way in ) horses inevitably bolt - albeit ours only enough to get away from the hornet nests / holes. NEVER let go of the saddle horn - always have one hand with a good grasp, and remain alert. Take allergy medicine / benedryl (sp?) syringes if you are allergic to bees ( I did not. In fact, I never gave a thought to them being "in the mountains.") I was lucky, out of a pack string of 8 horses and 4 humans, I was the only living thing that did NOT get stung. Believe me, I went to great lengths to avoid being stung. DON'T put your feet too far into the stirrups - pay attention to your outfitter when he gives you your horse instructions. NEVER take your eyes off the trail ahead. When you do, you will get smacked in the face by a low hanging branch or be jabbed somewhere by a protruding, sharp limb. That injury can be catastrophic. DO be prepared to lift your legs out of the stirrups as your horse closes the gap between trees, rocks, etc., on the trail. Failure to do so will result in a severely bruised (or worse) foot or leg. DO reign in your horse if he wants to trot, etc. Show him you are in control. Be mentally prepared for wilderness accomodations. A wilderness cabin - if you are in a cabin - is often not very tight. It has suffered bear intrusions, damage from storms, and it is like every other wood structure - rodents get into them. I had the luxury of a two pound pack rat running across my chest on the first night in my "suite." Beyond that, let your outfitter know what you NEED, as well as what you want. I'm a picky eater. Since I had successfully hunted with this outfitter on two previous occasions, he knew I was picky, and he accommodated me with the food I preferred - which was delicious. That made the down time more enjoyable, and I slept well. Let your outfitter know how you want to hunt, how hard, and what class of animal you are willing to settle for. Don't try to look at your outfitter's butt and try to read his / her mind...communicate! Remember that communication works both ways.
As far as getting ready, cardio ability is a given prerequisite. Additionally, I spent months with a focus on lower body (legs, thighs) and core (back & abdominal). More than one kinesiology / sports studies Doctor has told me that most people forget about the importance of core. It is as the name suggests - the core of your strength and support - the core supports all other muscles and your skeletal structure. Consult a knowledgeable professional and work on your core, a lot. Hydrate as soon as you walk out the door to start your trip. Make sure you have Gator Aid, etc. in your pack and at base camp. I suffer from debilitating abdominal and bowel cramps when I dehydrate - and it doesn't take much. The Gator Aid replenishes the sugar and electrolytes and quickly rids me of my symptoms. l rationed it and used it on my hunt. Pack a GPS, and a compass, (and a SPOT) and know how to use them. Don't rely completely on your guide. On another wilderness hunt, my outfitter's guide - built up by the outfitter to be quite the outdoorsman - failed to bring either with him. When we became temporarily lost in a heavy Wyoming snow storm, the guide asked ME which way was north. When I asked if he had a compass, he said no, he always relied on a prominent mountain peak for his reference. A lot of good that does in the frequent snow storms at 10,000 feet ! I pulled out my compass, and he did not believe the NORTH indicator - I had to convince him of my practice and familiarity with the compass. In that same storm, I had my snow / rain gear in the bottom of my pack. Don't do that ! I was wet by the time I got it on. Consequently, I was mildly hypothermic by the time we found the horses and rode the three hours back to camp. Luckily, the cook tent had a good fire in the stove and I got warmed up. Along that line, wear moisture wicking / breathable nylon, polyester or wool undergarments, etc. I have invested in cheap "packable" down garments to supplement my September bow hunt. I also take a homemade trauma kit, with a combat tourniquet, supplies to dress a sucking chest wound - you know, in case someone gets shot or cut - and a few other things to treat serious wounds. No, it does not take up much space in the pack. My philosophy - never put your life totally into the hands and preparation of another. That was a long one, but I hope it helps. Stand tall, shoot straight, and speak the truth ! Stay safe, everyone.