Mount Sanford (I think)
“I am nothing more than a single, narrow, gasping lung, floating over the mists and summits.”
-Reinhold Messner, Everest: Expedition to the Ultimate (1979).
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Air
When I was a teen, my dad spent two months preparing to reach the summit of Denali in Alaska, the highest peak in North America at just over 20,000-feet (about 6,200-meters). A physician, he was well aware of the need to acclimatize to the altitude.
During that time, I accompanied him and several others to the summit of Mount Sanford, at just under 5,000-meters, the highest elevation I’ve ever reached. I was fairly well acclimatized up to 3,500-meters at the time. Still, I well recall the thin air during the last day up to, and back from the summit.
A month in Japan, mostly in near sea-level Tokyo and Osaka, and I’m reminded that the Earth’s atmosphere is little more than a thin blanket. And the oxygen that I like to breath accounts for only about one-fifth of it.
Still, the atmosphere presses with almost fifteen pounds per square-inch (14.7 “psi”) at sea-level . The weight of all the air above, that’s more than a ton per square-foot! And though we don’t notice, our bodies push back with the same force.
Travel higher, and there’s less air above. So air-pressure decreases with altitude, by roughly one-half for every 18,000-feet (5,600-meters). At around 63,000-feet, it drops to a mere 0.9-psi, not even enough to keep human-body temperature water from boiling. (The “Armstrong limit”.)
Aside from keeping the fluids in our bodies from vaporizing, atmospheric pressure also pushes oxygen molecules close enough together for breathing. But with only half the pressure at 18,000-feet, only half as much oxygen is available as at sea-level. And at 29,000-feet, or the summit of Mount Everest, it’s only about one-third. And that’s not enough for human life.
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Humans at Altitude
In the US, I live at around 6,300-feet (≈2000-meters), so there’s about 20% less “oxygen pressure”. That’s enough to affect the human body, especially when exercising. Humans can adapt; but it takes time. And a month at sea-level is more than enough time to lose that adaptation.
Those not adapted may reflexively breathe more deeply (“hyperpnea”), or faster (“tachypnea”), and the heart may beat faster (“tachycardia”). But this can throw-off blood “pH” (acidity or alkalinity), eventually leading to a medical condition known as “alkalosis”. But this is only temporary.
Over about a week, kidneys will work to re-balance blood pH, a process that mountaineers can speed up with certain drugs, such as acetazolamide. But the kidneys also respond by secreting a hormone called “erythropoietin”, or “EPO”.
Most notably, EPO causes a gradual increase in red blood cells [“hematocrit” on a blood test]. Blood plasma also decreases, and more capillaries form in skeletal muscles. And the heart’s right ventricle may enlarge, increasing blood-pressure to the lungs. This all helps to more efficiently move oxygen.
Traveling to high altitudes without giving the body time to adapt can cause an illness known as “acute mountain sickness” (AMS). Severity can depend on elevation change, altitude, and rate of ascent. But AMS can be deadly.
Most who ascend from sea-level to 10,000-feet will experience some AMS symptoms for a few days, usually a headache and fatigue. Severe headaches, nausea, and difficulty with coordination might require descending to a lower elevation.
An inability to “get enough air” even when resting, and severe difficulties with coordination require immediate descent and medical attention, as they signal two potentially lethal forms of AMS.
A common thumbnail calculation for the time needed to fully adapt to an altitude is to multiply the elevation-change in kilometers (1,000-meters) by 11.5 days. So to fully adapt from sea-level to my home in the US at about 2,000-meters should take around 23-days.
Likewise, adapting to Base Camp at Mount Everest at around 5,200-meters (about 17,000-feet) should take about 60-days, assuming a start from sea-level. However, that pushes a limit. Most healthy humans can only adapt to long-terms up to about 5,000-meters (16,500-feet).
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Thin Air
The summit of Everest might now be reached by hundreds each year. But only a handful have done so without supplemental oxygen. Elevations above 8,000-meters are commonly called the “death zone” due to the thin air. In fact, until the mountaineers, Reinhold Messner and Peter Habeler, reached Everest’s summit without supplemental oxygen in 1978, it was a feat considered impossible.
Still, after months of acclimatization, the two mountaineers only barely succeeded. Falling to their knees in the snow to catch their breaths, Habeler began hallucinating. And Messner later described feeling as though he had lost his sense of “self” before literally crawling onto the summit.
In a later recollection of that moment, Messner declared that, “In my state of spiritual abstraction, I no longer belong to myself and to my eyesight. I am nothing more than a single narrow gasping lung, floating over the mists and summits.”
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V̇O2 max
“V̇O2 max” is a measure of how much oxygen a person can utilize during a physical activity; and it’s constrained by the rate of blood oxygen transport. Many aerobic athletes, such as bicyclists and runners, will train at high altitudes in the weeks before events to naturally increase this capacity. However, the use of synthetic EPO to artificially induce the effect is almost universally banned in sports as a form of “doping”. But there’s an odd gray area.
“Xenon” is a chemical element with the atomic number 54, and symbol “Xe”. It is a dense, colorless and odorless “noble gas” found in very small amounts in the Earth’s atmosphere. As a noble gas, like helium or argon, it’s generally non-reactive. However, the atom’s large size allows for some weak chemical interactions, including some that affect the human body.
Most importantly, breathing xenon can easily prove fatal. Not only can it displace the oxygen necessary for life, but high concentrations will also put a person to sleep in seconds. In fact, xenon is used for general anesthesia by trained physicians with proper equipment and careful administration. But a side effect is that it also stimulates the body to produce EPO.
The Russians apparently tried this with athletes at the Sochi Olympics, causing the World Anti-Doping Agency (WADA) to later ban xenon use. But whether xenon-elevated EPO really improves performance is still an open question, with no scientific studies demonstrating any advantage.
Regardless, four British military veterans just summited Mount Everest in a single week by using xenon to boost their red blood cell count while at sea-level. Under medical supervision, the four men inhaled a xenon-oxygen mix in a single administration that lasted less than an hour, with the hope that the greatest effects would occur 10 to 14 days afterward.
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Gas
Personally, I think this is mostly a stunt, with media (again) treating a press-release as “news”. The four men have also been sleeping and exercising for weeks in low oxygen environments, simulating the high altitudes. So this was more likely how they pre-acclimated their bodies. Still, Reinhold Messner has expressed his support of the process, including the use of xenon.
These guys did manage to make it from sea-level to the summit of Mount Everest in a mere week, a record to be sure… with months of medically-supervised preparation, a massive support team, and supplemental oxygen. To what extent this represents a “human” endeavor I suppose depends upon what technologies one considers as a part of the human identity, whether high-tech clothing, synthetic ropes and aluminum ladders, bottled oxygen, or medically administered xenon gas.
The whole point of “mountaineering” was once considered to be the challenge. Granted, I’m nowadays happy to make it up a local hill to enjoy the view. But Mount Everest, at least, seems to have been reduced to the status of reaching the top of a tabloid news cycle with an expensive selfie.
References (though there’s plenty of media coverage):
Dias, K. A., Lawley, J. S., Gatterer, H., Howden, E. J., Sarma, S., Cornwell, W. K., Hearon, C. M., Samels, M., Everding, B., Liang, A. S., Hendrix, M., Piper, T., Thevis, M., Bruick, R. K., & Levine, B. D. (2019). Effect of acute and chronic xenon inhalation on erythropoietin, hematological parameters, and athletic performance. Journal of Applied Physiology, 127(6), 1503–1510. https://doi.org/10.1152/japplphysiol.00289.2019
Horwath, H. (2020, January 3). Blood Doping and EPO: An Anti-Doping FAQ | USADA. U.S. Anti-Doping Agency (USADA). https://www.usada.org/spirit-of-sport/blood-doping-epo-faq/
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