The red blood cells carry oxygen from the lungs to the body tissue and carbon dioxide discard away from the tissue and back to the lungs. Hemoglobin (Hgb) is the key protein in the cells that transports oxygen from the lungs. When you go to higher altitude your blood changes and makes more red blood cells to " increase traffic" on the highway and carry more per say.
Key factors in not getting altitude sickness are:
1) Stepping up to altitude so the blood changes naturally. Ex...I take my Dad from 300' to 8000' day one. Spend 24 hours there then 8000'to 10000' day 2. That alone makes a big difference.......more days even better.
2) Start eating differently 14 days out from the hunt. Beef, Organs kidney and liver, spinach, kale, prunes, raisins, legumes and egg yolks will increase overall red blood cell count.
3) Hydrate. With relatively no humidity in Colorado it sucks the moisture out at a higher rate. Drink before going to bed. Drink one of the many cardio enhancing products out there. Enduro by Mountain Ops is what I have in camp.
I am not a Doctor, Nutritionist nor do I have a sponsorship from MTN OPS.........but I do take a lot of dudes up hi from sea level and thats what has worked in my camps.
All the best, tag results should be out soon.