Acclimatization

Climbing Mount Everest without supplemental oxygen requires 70 ml/kg/min oxygen uptake capacity and 70 – 100 days of acclimatization

Hello, this time the topic of the blog is about how to get to the top without oxygen equipment. I have researched the topic for three years from different sources and found out which factors influence adaptation to the greatest challenge of the Himalayan peak.

In today’s blog, we will consider cause-and-effect relationships from the conditions of Everest’s solution point (8000 m) to physiological requirements, correlations and consideration of whether, in addition to oxygen uptake and acclimatization time, there is an adaptation factor X or not. The story could become topics for several degrees, and the fieldwork could be interesting, but challenging.

Interesting reading experiences!

Lack of oxygen is the biggest challenge on Mount Everest

The summit ridge of Mount Everest has 1/3 the oxygen compared to sea level

When moving from sea level to a higher air pressure, the partial pressure of oxygen also decreases in the same proportion. At the top of Everest, at an altitude of just under 9,000 meters, the air pressure is about 30% of sea level, so the partial pressure of oxygen is correspondingly 30% of sea level, i.e. significantly less oxygen is available, which means that mountain climbing is almost impossible.

“When climbing Mount Everest, the biggest challenge is the amount of oxygen above 8,000 meters.” – Jussi Haikka

The oxygen uptake capacity drops by 70% when going from sea level to the top, which means that the maximum oxygen uptake capacity of 70 ml/kg/min drops to the level of 21 ml/kg/min. Correspondingly, the oxygen uptake capacity of the aerobic threshold decreases from the level of 40 ml/kg/min to the level of 12 ml/kg/min, which theoretically enables an ascent of 1000 meters in 4 hours with the equipment, but in practice in 8 hours.

The amount of oxygen is also affected by the season and the weather. In summer, there is more high pressure, so more oxygen is available. In addition, in windy weather, more oxygen is used to overcome wind resistance, and in cold weather, the body uses energy and oxygen in the same way as a cold car engine uses fuel. You should literally visit the top during good weather.

During the mountain climbing project, I also got access to public material related to the training of fighter pilots, which tells about human physiology and symptoms of lack of oxygen. I will come back to the topic later when I update the blog.

A flight to an altitude of 8,000 meters? – the body’s physiological function at over 8,000 meters

In order for movement at the height of passenger planes, seven kilometers above the skyscrapers of Manhattan, to be possible without oxygen equipment, the oxygen uptake capacity, i.e. the body’s ability to oxygenate the muscles during exercise, must be good enough at around 65 – 70 ml/kg/min. The level in question corresponds to the level of the maximum oxygen uptake capacity of Olympic skiers. From the above-mentioned measurement unit, you can see that the body mass (77 kg) and portable mass (15 – 20 kg) are relevant, along with the absolute oxygen uptake capacity (l/min).

“If a person is taken directly from sea level to an altitude of 8,000 meters, he will die from lack of oxygen in less than four minutes.” (scientific articles)

If a mountaineer is too high for too long, he develops life-threatening mountain sickness. At an altitude of more than 8,000 meters, the aim is to move as quickly as possible. When moving briskly, however, the body’s oxygen content decreases, so the pace must be optimized so that the minimum time spent at an altitude of more than 8,000 meters is as little as possible, while maintaining the body’s oxygen levels and ability to function in the arctic peak wind. In practice, it means a regular and sufficient supply of energy and hot water during 30 hours of peak performance.

Death Zone

“Above 8,000 meters there is a death zone, just like when crossing a highway. If you stand too long on the highway, you will die.”

At an altitude of 8,000 meters, the body no longer recovers, but begins to die a slow death, so it is not worth spending any extra time there. According to the information I received, 6500 meters is the highest long-term altitude where a person has lived for months. According to my own assessment, the highest possible limit of acclimatization is at an altitude of 7,000 meters, so it is no longer possible to adapt above that for a long time, because the body starts to wear out due to the lack of oxygen. However, there is about 10% more oxygen at an altitude of 7,000 meters than at an altitude of 8,000 meters, so the body does not wear out any more there after the summit. 7000 meters is the highest altitude from which you can rescue on foot and from 6000 meters by helicopter, so it also advocates descending from the summit directly to the C3 base at 7100 meters.

Mountain sickness

Mountain sickness is caused by too little oxygen intake for too long. Finnish doctor of medicine Heikki Karinen has researched and done distinguished field work in the Himalayan mountains and a dissertation on mountain sickness. I have consulted Heikki Karis a few times and read his articles on mountain sickness and its first measures.

Oxygen saturation (PO2) and wrist pulse oximeter

“Oxygen saturation means the oxygen content of the blood, which can be measured with an oxygen saturation or pulse oximeter.” (Medidyne, scientific articles)

My first sponsor, Medidyne Nordic, has given me a new technology product, a wrist pulse oximeter, where the sensor is on the end of the finger and the meter is on the wrist. The oxygen saturation meter I got is like a reverse car speedometer. If the reading drops too low, the ascent must be interrupted and the altitude must be lowered by 500 meters. When moving, the oxygen content of the blood, i.e. oxygen saturation, is lower than at rest, and monitoring it can be challenging in mountain conditions.

Another way is to use an oxygen saturation monitor while at rest. Mountain sickness usually comes with a delay in relation to the level of acclimatization, ability to acclimatize, increased altitude and speed of ascent and it usually starts in the morning. If the reading of the oxygen saturation meter is too low, you have to get out of the sleeping bag and immediately start descending on the dark and cold mountain to an altitude 500 meters lower.

In addition to Medidyne’s oxygen saturation meter, the Oura smart ring (gen3) is getting an oxygen saturation feature as an update during 2022.

Lake Louise testing

(I write later)

1. Correlation of oxygen uptake capacity (MAX VO2) to summiting Mount Everest without supplemental oxygen

1.1 Correlation of oxygen uptake with peak probability

“According to research from the 1980s, oxygen uptake capacity has a clear correlation with peaking probability.” (scientific articles)

When climbing with oxygen bottles, the height of 8,849 meters corresponds to an altitude of about 6,000 meters in terms of oxygen partial pressure, which means that the oxygen absorption capacity only needs to be 70% compared to climbing to the top without oxygen bottles. In practice, for Marathon, it means less than three hours without supplemental oxygen, and 4.5 hours for oxygen bottle users.

1.2 Oxygen uptake (VO2) testing

(I write later)

1.3 The importance of power output for performance and oxygen consumption

“In an optimal situation, a mountain climber has a relatively high power output, a light body weight and a durable big engine – the heart.” – Jussi Haikka

The body’s ability to generate power is important for performance and oxygen consumption when moving 15 to 20 kg with equipment uphill. For a smaller size, 20 kg basic load in the upper mountains increases the total mass to be carried relatively more than for a larger size mountaineer. The larger volume of a larger body is beneficial both against the effect of frost and in terms of energy and power production. The lightweight mountain climber weighs less, so it is naturally lighter and faster to transport. However, the harsh conditions of the mountains also require momentary power generation ability in difficult conditions, because moving in easy terrain becomes extremely difficult, if not impossible, in a storm.

1.4 Effect of additional range on rate of climb and performance factor

In my own field studies, I have found that 10% additional bearing slows down the speed by a constant 10% (Cooper’s test). Similarly, in my own field studies on a 20-degree uphill, a 10% bearing has slowed down the speed by 20%. So the kilos carried on the uphill are at least double. There is no unequivocal formula, but the conclusion is that the mass to be carried must be lowered and the endurance condition and maximum strength levels must be raised.

“Uphill, a 10% bearing slows you down by 20%.” – Jussi Haikka

While calculating the time from different heights to the top and back, I ended up comparing my own condition with the condition of mountain runner Kilian Jornet, when I knew the time of both in a 10,000 meter run. As a result, I ended up with the fact that compared to Kilian Jornett, my performance coefficient is 1.20. When increasing the load capacity to 20 kg, the difference equalizes to a factor of 1.15. On the other hand, he has more experience of his own limits in the mountains, so the practical performance factor in terms of time is 1.25. The performance factor helps determine the time needed to move in the mountains. However, it is unusable when moving from Everest to steeper terrains.

2. Acclimatization time and altitude

 

Acclimatization 22 of April 2022