i’ve read several of the books that came out describing the 1996 expeditions and deaths on mt. everest. all of them talk about people that can reach the 29,000+ foot summit without using supplemental oxygen, due to their unique physiology. somehow their bodies process oxygen more efficiently than others.
what is the physiology behind this? more of something? less of something?
Basically, their bodies produce more red blood cells.
RBC’s are what carry the oxygen in the blood, but like just about any complicated process, the extraction of O2 from the air and dissolution into the blood is far from 100% efficient. At lower altitudes, failing to extract 50% of the oxygen from each breath is minor, since there’s so much of it. At altitude, your body needs to etract as much O2 as it can. More RBCs = more oxygen carrying capacity of the blood. This is why endurance athletes train at altitude, like in Denver or the Kenyan runners. When they return to sea level, their blood is that much more efficient at carrying oxygen to the body.
there are two possible physiological phenomena that could be responsible for such a feet. their technical terms are: excessive stupidity and machismo overabundance. either (or both) of these attributes might cause someone to attempt this.
So if I find myself at altitude and can’t process the O2, can I just give myself a shot of Epogen (erthyropoeitin) to stimulate red blood cell production?
I’d heard it’s one of the best drugs for athletes to ‘dope’ on in the Olympics since it is naturally occuring in the body and difficult to detect in terms of a post-victory drug test.
Actually, neither of these will prove helpful at 8000 Km, as they aren’t helpful at sea-level.
IIRC, Meisner was the first to do Everest without supplemental O2. Among good reasons (not necessarily his reasons) are that you can move faster without lugging heavy bottles around (very important when the window of opportunity is short due to bad weather); there’s less impact on the environment (lots of a__holes don’t pack their bottles out); and that whole ‘purity’ thing (some people feel carrying O2 is ‘cheating’.)
It makes no difference to me; I’m a smoker and fall asleep at about 18,000 feet.
From what I’ve read, “functioning” up there is kind of a relative term.
With sufficient acclimatization (literally weeks), people in good shape can adapt to that high altitude. As in, they won’t pass out within minutes like the average person would if they were to suddenly materialize up there. However, nobody adapts to the point that they can continue to live/work indefinitely at 29,000 feet.
The climb then becomes something of a delicate balance: ascend too quickly, and the body fails to acclimatize and you won’t be able to function (high-altitude sickness can be fatal); ascend too slowly, and the prolonged stay at those altitudes will gradually sap your strength and you’ll just run out of reserves before you reach the top.
And for the non-sports physicians reading this thread, maybe you could tell us what this means?
jk1245, brad_d, the rest of you: can’t exposure to low air pressure and O[sub]2[/sub] levels cause permanent brain damage? Can this happen to a mountain climber in the time he usually spends in such environments?
from what i’ve read, high altitude climbers call anything above 25,000 feet the ‘death zone’. this is where, regardless of your physiology, your body and brain deteriorate from lack of oxygen. there is no physical conditioning to be done at this altitude. once they reach this level, climbers want to reach the summit and get the hell out of there before permanent damage sets in.
i personally don’t see why anyone would want to spend any time at all in the ‘death zone’. as a skier and mountain biker, i can understand the need to improve your skill and challenge yourself by conquering new and more difficult terrain, but not to the point where you have diminishing returns on your body.
I’ve also heard (don’t y’all love my reference-free posts?) that people who live at high altitudes, like La Paz, Bolivia, have as much as a pint more blood than someone else (all variables being equal) living at sea level. Is this true? Do they actually have more blood volume, as opposed to just having more RBC’s?
I’ve also heard that folks living at altitude (I believe I heard it of Andeans, but it probably applies to Himalayans, as well) have more mitochondria per cell. (The mitochondrion is the cell organelle responsible for most of the work of breaking down sugars into ATP, the cell’s energy source.)
“Studies of residents of the Andes show average hematocrit levels of 59 percent in males living at 14,800 feet, 52.2 percent at 12,000 feet, and 50.4 percent at 10,400 feet [Reynafarje et al. 1959; Winslow et al. 1987, 1989]. Himalayan residents living at similar altitudes seem to have slightly lower hematocrit concentrations [Winslow et al. 1989]. One could perhaps expect athletes living at these altitudes to have even higher values, as athletes generally show higher hematocrit concentrations and higher blood volume than the average population. After 40 days, members of a Himalayan expedition living at 14,600 feet had hematocrit concentrations of 55 per-cent [Milledge and Cotes 1985]. If someone were to normally have a hematocrit of 40 per-cent, an increase to 57 percent indicates 30 percent more red blood cells; assuming hard training at low altitude were ongoing, one could expect much higher performance! Also, some studies indicate that blood serum also increases at altitude, so the relative increase in red cells could be even higher yet, as total blood volume has increased.”
Brain Damage - absolutely. See the Nova episode about Everest and oxygen, with Ed Vestiers and David Breashers. As little as one trip above 25,000’ can leave people with noticable changes on their brain scans. And the effects seem to be cummulative.
So does it follow that people living in La Paz and similar high altitudes would score poorly on standardized tests and motor skills tests, and generally be a bunch of Beavises?