When muscles don’t have enough oxygen, this is what happens: they are forced to work harder and harder and they get tired more. Physical tasks in general become even more difficult. Your body feels slow and heavy, and you begin to feel tired and weighed down. As a result, appetite decreases, and the food you eat, can’t be digested properly. This leads to calorie deficit that makes you even more tired and weak. To avoid dehydration, climbers melt snow. But because of the process their bodies are going through, they feel too tired to do that and become dehydrated. They can’t even sleep sufficiently and efficiently because of the lack of oxygen. There are psychological symptoms as well, since it’s well known, that the physical body is connected to our mental and emotional state. A climber begins to feel helpless, vulnerable and depressed, and can even experience panic as a sort of climax of the emotional trauma he experiences. Hallucinations are also common, and so is cloud judgment. All these terms can eventually lead to nausea, swelling in the brain, fluids in the lungs, and consequently, death. Even people who recovered, later had discovered that they had suffered a permanent brain damage as a result.
Biophysicist Thomas f. Hornbein, who climbed Mount Everest in 1963, stated that climbers without oxygen, experience the height of being on the top of the mountain two times worse than climbers with oxygen. A climber who rests on a mountain top and breathes bottled oxygen at three liters per minute, feels as if he was 15000 feet lower – almost as half the height.
As you see, although glorious, it’s not a piece of cake. All that is with the extra oxygen! Wonder what its is like when you don’t use oxygen tanks at all.