#Chimborazo2015 Expedition Post 7: Gill’s Blog - Zero Calorie Climbing
Published on October, 17th 2015
By Greg Wells
To anyone who has had the hubris to say the words “I don’t get altitude sickness” – listen up. We started our trek at 3400 m, hiking 18 km on mountain dirt roads that make up the old Inca trail from the coast, which eventually joins up with a true trail on a very steep mountain side covered in golden grass that makes you run your hands through it like you’re Russell Crow in Gladiator. When we arrived at the Chimborazo Lodge at 4000 m, Sara and I had been above 2500 m for 4 nights and 3 full days with nothing to complain about besides higher heart rates (or at least mine was) and heavy breathing walking up stairs. The whole 18 km, I was thinking “this isn’t so bad”, although catching up with the group after taking pictures or doing an interview made the legs burn and my heart rate was much higher than I expected to the point where I thought the watch was broken. This façade among others came crashing down about 1 hour into our settling in at the Lodge when I threw up as many times as I’ve said the words “I’ve never had altitude sickness” – which, unfortunately for me, is a lot.
Naturally, I attributed this impossible occurrence to drinking the tap water in Quito. As the last 3 days have passed, I’ve slowly had to come to the realization that I have Acute Mountain Sickness. It’s extremely demoralizing, as I’ve been to altitude a number of times and just considered myself one of those people who “doesn’t react to altitude” – if you’re one of those people, heed warning. It can happen. And while climbing from 4000 m to 4800 m vertical over 9 km on climb day 2, or 4800-5500 m vertical over 4.5 km (that means it’s steep) on climb day 3 is hard enough as a sea level dweller, it is that much worse with a stomach ache, no calories staying in your body, and (my biggest concern) a serious lack of water staying in my circulation. The voiding of what I take in is rough but it comes with a complete lack of compulsion to take in either calories or water. It took me 2 h to eat half of a granola bar (65 calories) this morning and according to my Polar watch, I’m averaging 2000 calories a day on the climbs (so added to the ~1500 calories that I’m probably burning in general, that’s about a pound of fat a day). Previous measurements of caloric expenditures at altitudes similar to what we’re experiencing are between 3000-5000 calories per day (Miller et al. 2013)…so in short, I’m running at a serious deficit here.
It’s also showing in my blood work and pulse oximetry measures. My blood oxygen saturation was about 67% for the 700 m ascent today, my heart rate is about 150bpm for any uphill climbing (according to my Polar software, that was 44% of my climbing day), and while my hematocrit is over 50 and I should be legally banned from competition for blood doping, I am decidedly not performance enhanced, as this is a byproduct of my dehydration (termed “hemoconcentration”, you lose plasma volume from your blood to increase cell content to facilitate O2 binding at the lungs). The effect of hemoconcentration is a loss of about 3-5 ml/kg of bodyweight at altitudes above 3500 m (Mason 2000) in addition to respiratory losses (due to drier air and hyperventilation) and sweating from exertion. The dehydration is probably responsible for my high heart rate, since with less overall blood volume the heart has to beat more times to maintain the same output to support my hiking. So, my major concern is the potential implications of this continued dehydration and that is where my priority is (I’m pretty sure my body can find some sources of energy if it looks hard enough…). I’ve been adding salt to any food I take in to help promote uptake of water into my blood and keep it there (by osmotic influence) and to drink as much as I can in small volumes so I don’t immediately pee it out. I ate more than half of my dinner, which is a huge win, so hopefully I can keep it in my body tonight.
Despite this terrible insult to my self-identity, the experience so far has been absolutely incredible. Our guide Marco Cruz is a living legend, the mountain is beautiful and I can’t take enough pictures, and even though each step takes more breaths than a fast jog at home, I am just so stoked to be here and am really having a good time. At the end of the day, being humbled by the mountain is probably just as important as anything else I learn while I’m out here.
Mason NP. The physiology of high altitude: an introduction to the cardiorespiratory changes occurring on ascent to altitude. Current Anesthesia and Critical Care 2000; 11: 34-41.
Miller AD, Taylor BJ, Johnson BD. Energy expenditure and intensity levels during a 6170m summit in the Karakoram Mountains. Wilderness & Environmental Medicine 2013; 24:337-344.