I absolutely agree with making multiple 3-5 day hunts as opposed to one long 10 day hunt, especially for you first trip. At the end of day 4, you can go back to the truck, dump of 75% of the gear that you packed, that you actually do not need, refuel your supplies that you do need, and run into town to grab the greasiest, most delicious cheeseburger you can find.
I felt like packing for the 10 day trip kind of tied me down a little, as it's just too hard to pack all of your stuff around, all of the time.. You end up leaving your tent and all your other gear in a camp, and have to hunt back to it each night. Packing for 3-5 days, you can easily carry everything, and just camp where you end up at night. To get ready for the trip, I ran, alot. And did lots of weight training for my legs and core. I never really consentrated on my upper body. After I felt like I was starting to progress in my running and weight training, I laced up my boots that I would be wearing on the trip, and loaded my pack up with 50 pounds, and found the tallest hill around and started hiking it. I quickly realized I was NOT in shape.
I slowly started increasing the weight in my pack until I was at 75 pounds a month before my hunt. I toted 75 pounds up and down a 200ft hill (best I could do in Missouri) 4 times a week for 3 weeks. By the time I got to Colorado, my 60 pound pack felt pretty light, and I had no issues.
Get in mountain shape, and you'll have a blast regardless of the outcome. Don't get in shape, and you'll be looking for any excuse to get off the mountain.
You have to make sure you're in shape, or else you will be miserable. We hunted 9 days straight last year, never dropping below 10,500 feet, and I felt like I owned the mountain by the time we were done. To get