Acclimatization

How it Works
Climbing at altitude needs an adaptation of the body functions to altitude: acclimatization.
Due to the low air pressure, the higher we climb, the less able is our body to obtain oxygen. In the Himalayas this happens above 5000m, depending on the individual.
Therefore we will need to force the body to produce more red cells in the blood. This is attained by climbing additional 800-1000m than the previous maximum altitude we were at, then retrieving to the base camp to allow the body to "digest" the alterations it is being subjected to.
If we went straight to altitude we could maybe climb 2000m in two days but we would risk becoming seriously sick with a edema: pulmonary or cerebral, or both and never return!
For a 8000m high mountain without great technical difficulties with a not too long itinerary we will need three to four climbs.
My method is that after each climb I sleep there, reinforcing the process.
Apart from the acclimatization evolution described there is also the need to place altitude camps. For each climb we carry tent, gaz, sleeping bags, food, ropes, etc. The tents stay there during the whole expedition mainly the ones at C1 and C2.
I show below a diagram of climbs and rest.
Normally 2 days rest between climbs is enough.
During the third climb, if we feel well, physically and psychologically, after placing camp 3 we may go to the summit in the early hours of the following day.
This should happen if there would be a terrible weather forecast for the following week!
Or we may opt to return to BC, rest 3 days and go up very light because all camps are already equipped with all food, gaz and equipment we will need for the summit push.
This schedule cannot be precise because we may face periods of bad weather with forced stays at BC. Frequent snow falls can also delay us because we would need to redo the trail and this is very energy consuming! If a big snow fall takes place the mountain will become safe again after 2-3 days of sunshine.
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