Altitude

In a number of activities, going the extra yard tends to be harder than the couple of yards just before. If you run a 10K, it will be very demanding to add another kilometer onto it, although running one kilometer might sounds like a piece of piss for you. If you work 50 hours a week, the 51st hour will be extremely painful, a lot more than the first hour of that week (well, depending on the night before I suppose!). For a number of natural reasons, it goes the same with altitude. I regularly jog 450meters of positive elevation here in Heidelberg, but when you're at 3000m, the next 450m will take you a lot more energy. If you're at 4000m you might start wondering if you're even able to do the extra 450m and you don't stand a chance if you didn't prepare. At 5000m, you might actually put yourself in real trouble by attempting further elevation gain without adequate acclimatisation.

The following website is amazingly interesting for those who want to know more about high altitude: http://www.altitude.org/high_altitude.php

Basically air gets thinner with altitude, and the closer you are to the poles the less oxygen you will find at a given altitude. Your body needs the oxygen to keep going, so you start breathing harder and faster and your heart starts beating harder and faster to keep muscles and brains fed. With lower air pressure, a red cell will carry less oxygen than it would at sea level. At a certain altitude this won't suffice, as your lungs and heart cannot race forever. This is where you need long periods of rest so that your body adapts to the fact that there is simply less air to breathe. Your body starts producing more red cells, so that you can capture more oxygen out of a given amount of air going through your lungs. With more red cells, your blood becomes thicker and therefore harder to pump.

The best way to acclimatise is to rest at high altitude, ideally spend a night up there. In the alps you can stay over at one of the huts, try ot catch some sleep. After a couple of days going around in the mountains, you might attempt to climb up to 4000m, maybe 4200m, but to have a go at a Mont Blanc and its 4810m, you need almost a week of acclimatisation, making this summit more challenging than it looks. On the Kilimanjaro we spent the whole week accliimatising at altitudes between 3000m and 4600m before attempting the summit (5895m). On the website above, I read that this is nonsense and we were not properly acclimatised when attempting the summit. Testosterone might get you there, but you're putting yourself in danger!

Some medicines might help you bear the effects of altitude for a given amount of time, but the only way to keep going is to spend time acclimatising. On the summit day (or night) of Kilimanjaro our little group was affected in various ways by the high altitude: cold, headache, belly ache, dizziness, loss of balance, loss of consciousness, heart&lungs limit.

On summits above 6000m, you would typically set-up a base camp around 4500-5000m, and wander to higher altitudes on one or two days-trips to further stimulate your body acclimatisation process. Depending on the altitude you're trying to reach, you will then move to your advanced camps and have a go at the summit. For Mount Everest there are typically 3 or 4 acclimatisation climbs from base camp before climbers attempt the 8848m summit, most of the time with additional supplies of oxygen.

Of course the temperature falls with altitude, so you don't only fight the lack of oxygen, but also arctic temperatures. Altitude complications include hypothermia (dying of cold), acute mountain sickness, high-altitude pulmonary oedema, high-altitude cerebral oedema. Above 7500m your body is not able to acclimatise, it can only deteriorate. This is called the death zone, a countdown to your death. Depending on people and on your preparation, you have a certain number of hours to live before you die. If you can't reach your summit before then, you have to hurry back down the mountain. And by the way, forget helicopters. Above 4000m-4500m, there is not enough air for them to fly.