Your Ultra-Training Bag of Tricks: Altitude Training and Racing

When Sir Roger Bannister, a neurologist and the first person to break the 4-minute mile, was asked what he thought it would take to become fully acclimatized to altitude he responded, “There are two ways. Be born at altitude…or train there for 25 years.” Unfortunately, the majority of runners participating in high altitude ultramarathons don’t fall into either category. In this piece, I attempt to summarize some of the existing information and relate it to our sport in the hopes of arming the altitude-disadvantaged athlete with some basic knowledge to be better prepared for events at elevation. Keep in mind that the majority of scientific studies published on altitude and its effects have focused on and benefited athletes preparing for national, world, and Olympic events from the marathon on down. Though a lot of anecdotal evidence is out there, very little research has been done in the way of clarifying how it specifically impacts the ultrarunner.

Sucking Wind

The sea-level dwelling athlete’s first reaction to high altitude running is best described like this, “I feel like I have a sock in my mouth, a vise on my head, and I’m running in wet cement.” It’s an awful feeling. Why does our effort increase and performance decrease when we run at higher elevations?

The air around us provides the oxygen we need to run. We breathe this oxygen into our lungs, which is then transported into the blood stream, and is then carried by hemoglobin to the working muscles. Traveling up in altitude relinquishes gravity’s hold on the air around us and causes atmospheric pressure to drop. Though the percentage of oxygen remains the same, the lack of pressure keeping these molecules together lessens allowing oxygen (as well as other atmospheric gases) to disperse and affects oxygen’s rate of absorption through lung membranes. Though lung capacity remains the same at altitude, the shortage of oxygen and lower atmospheric pressure makes it impossible to get the same amount of oxygen to the muscles in each breath compared to being at sea level.

Simply put, at altitude we are suffering from hypoxia—when the working tissues of the body are deprived of adequate oxygen supply. This phenomenon triggers a cascade of physiological events.

Channeling the Incredible Hulk

Though we don’t actually turn green, many of us feel flu-like symptoms or hungover when initially presented with high altitude conditions. Like David Banner during a Hulk rage, we undergo significant internal changes.

Immediately upon exposure to higher altitude:

  • Blood plasma, the “water” of our blood, levels decrease rapidly in order to increase the density of red blood cells and oxygen carrying hemoglobin being pumped through the circulatory system.
  • Due to this initial drop in plasma, stroke volume (the amount of liquid pushed through the heart) decreases, and in turn heart rate increases to compensate.
  • Breathing rates increase both at rest and during exercise to bring more oxygen into the lungs.

In roughly two weeks’ time:

  • Plasma levels return to normal and oxygen uptake becomes efficient.
  • Resting heart rates, depending on the individual, either remain high or return to that of their sea-level value.
  • Maximal heart rate remains unchanged but is achieved at a much lower work rate than at sea level.
  • Muscle mitochondria (the cell’s power producers) increase in size and number and there’s a greater reliance on fatty acids as the primary fuel source rather than glycogen during exercise.
  • Kidneys increase their output of the hormone erythropoietin (EPO) that stimulates bone marrow to increase red blood cell and hemoglobin production.

Who is Affected by Altitude When Running?

Both scientific studies and anecdotal evidence support the fact that running and racing at altitude is difficult for all athletes, no matter their level of fitness.

In a widely referenced 1982 study, Squires and Buskirk found a predictable reduction in VO2 max of approximately 8% for every 1,000 meters (3,280’) above 700 meters (~2,300’). Remember, from the previous speed-based workout column, that VO2 max refers to the maximum amount of oxygen an individual can use during intense exercise. The more oxygen one can utilize during hard bouts of exercise, the higher their VO2 max, and the more power produced during a workout. Naturally, if there is less oxygen (like at altitude) then VO2 max will suffer.

Jim Ryun, a former mile world-record holder, had to stop a quarter mile into his first run at 8,000’. His first mile time trial in Alamosa, Colorado, was 4:32, 37 seconds slower than his most recent mile at sea level

Ryan Hall, an accomplished 2:04:55 marathoner, describes altitude running like this, “Running at altitude is hard. Don’t feel like you are experiencing anything different from anyone else when you find yourself out of breath at the top of stairs or taste blood after a hard workout because we all feel it.”

Because the effects are so real, a number of institutions, including the NCAA and USATF, make allowances for race results at altitude. When attempting to qualify for a 10K championship race, for example, in Boone, NC (3,300’), collegiate men receive a 30 second adjustment; in Boulder, CO (5,200’), the allowance is 64 seconds; 10,000 meters on Northern Arizona University’s track in Flagstaff, AZ, (6,900’) is given a 99 second improvement; and while in Gunnison, CO (7,700’), runners lop off two full minutes from their posted time.

Preparing for Running Altitude

Though the side effects of altitude are inevitable and unavoidable, there are several things we can do to ready our minds and bodies for the experience. Because of the wide-ranging reactions individuals undergo at altitude there are both debatable and accepted training techniques.

1) Accepted. If a sea-level trained athlete travels to a race at elevations above what she is used to, the best course of action is to compete immediately upon arrival. If more time were available, a stint at the competition’s location of three to four weeks, the point at which most physiological adaptations have reached stasis, would be ideal. It is important to note that after the first 24 hours at high altitude dehydration and sleep disturbances can become more obvious, however, other negative effects (for example plasma density variations and increased breath and heart rate) will be noticeable even before the 24-hour window is reached.

2) Accepted. If you’ve just moved to altitude for a prolonged period of time, workout intensity should be reduced during the first two weeks while your body adjusts. Train no harder than your sea level easy run and long run training efforts for this brief period.

3) Accepted. Race and train at a slower pace. “On an easy and flat 8- to 10-mile run at 7,000 feet you can expect to move a full 20 to 30 seconds per mile slower than during the same distance at sea level. I suggest putting the GPS away and running by effort rather than by pace in the mountains,” says Flagstaff-based coach Greg McMillan. Running by feel is your best tactic while racing and training at altitude. Running too aggressively too often will lead to overtraining.

Darcy Africa racing at altitude at the 2011 Hardrock 100. Photo: Bryon Powell

4) Accepted. Recovery while living and training at altitude, due to the lack of oxygen, is even more important than at sea level. Runners who don’t monitor their work output or eat properly can become anemic, experience muscle loss, and suffer from long bouts of muscle soreness and fatigue.

5) Accepted. In preparation for competition at altitude, focus on several weeks of VO2 max workouts at sea level to help prepare the body for the efforts you’ll experience. Here are two examples:

  • Short Hill Repeats: The workouts will build leg strength and increase VO2 max. Find a hill with a medium slope (6% -10%) that takes between 45-90 seconds to ascend. Run up at an effort equivalent to your 5k race pace. Focus on good form with powerful push off and strong arm swing. Slowly jog down the hill to recover. Start with 4 to 6 repeats and build up to 12 to 14 reps.
  • VO2 max intervals: These should last between one and six minutes with paces that emulate an 8- to 15-minute race. They’re tough so recover with a jog or walk that lasts the length of the fast repeat. Complete 6 to 30 minutes of VO2 max work during each workout depending on your experience and fitness level.

6) Accepted. Acute mountain sickness can be experienced as low as 6,000’, within the first six hours of exposure, and can last for up for as long as two days. Symptoms are headache, fatigue, dizziness, and sleep and stomach distress. Remedies include many natural remedies, proper hydration, retuning to lower elevation, supplemental oxygen, or medication containing acetazolamide (Diamox).

7) Debatable. Altitude simulation. Recent studies have shown that “real-world” altitude situations where both the oxygen content and the atmospheric pressure are low are more beneficial for acclimatization. Other studies have concluded that tools such as an altitude tent may have to be used for 16+ hours a day to yield benefits for the athlete. Altitude tents reduce the oxygen content in the air within them thus allowing the athlete to produce more red blood cells, but they cannot alter atmospheric pressure. Masks may increase lung capacity and power, but cannot modify pressure, oxygen content, or be worn all day.

8) Accepted. Meredith Terranova, an Austin-based sports nutritionist, explains why altitude training and racing increases fluid and nutrition requirements, “Due to an increased dependence of blood glucose as fuel, fatigue and low blood sugar levels occur more rapidly at altitude compared to sea level. Because the air at altitude is cold and dry, water and sodium (through sweat and respiration) are lost to the environment more quickly. In addition, at high altitude, food digestion efficiency declines as the body suppresses the digestive system in favor of cardiopulmonary functions like heart rate and stroke volume.”

Terranova, referencing an online Triathlete article by Pip Taylor, recommends that athletes training and living at high altitude follow these guidelines:

  • Hydration. Extra fluid intake is essential. Higher altitude means that breathing is shallower and more frequent; this increased ventilation along with dry air leads to greater fluid losses through the respiratory system. Because sweat evaporates quickly, you can be led to believe that you are not losing much fluid and will be less inclined to drink.
  • Fuel Utilization. Basal metabolic rate (BMR), the amount of energy used a rest or sleep, increases at altitude, especially in the first couple of days. Appetite is also suppressed by hypoxia. To minimize reduction in body mass and loss of muscle, take care to match your caloric needs. During acclimatization, BMR will slowly return to normal, but not quite to base level (sea level rate). There also seems to be a shift in fuel utilization toward a greater reliance on carbohydrate as opposed to fat stores. Upon reaching altitude, consider frequent small meals that are carbohydrate-rich to maintain energy levels.
  • Iron Stress. Iron is required to manufacture hemoglobin (the oxygen-binding portion of red blood cells). As the body tries to adapt to the lower oxygen concentrations a greater number of red blood cells are produced. Before you go to altitude, consider having a blood test to ensure your iron stores are adequate. Talk to your doctor about considering the use of iron supplements and be sure to include iron-rich foods in your diet.
  • Immune Stress. Altitude and hard training places a hard-hitting combination of stress on the body. A diet rich in natural antioxidants is important to help the body adjust and remain healthy with the demands you’ll be placing upon it.

Altitude Acclimation Strategies

  • Live high, train high – You’ll be very good at training and racing at altitude. Expect to never achieve comparable sea-level training paces and race PRs while at altitude. Great for runners who gravitate towards high mountain courses, like Leadville, Hardrock, and Wasatch.
  • Live high, train low – By training near sea level and living at elevation you gain the benefits of altitude without losing your racing fitness because you’ll be able to perform workouts at “real” VO2 max levels. However, there are not many locations that fit these parameters. Due to each individual’s reaction to the “high” component, the outcome of this strategy will vary significantly from one person to the next.
  • Live low, train high – Though, physiologically, no gains are made, mentally you will be more prepared for the event as you’ll be familiar with the effects of high altitude on your body and how to pace yourself under those conditions.
  • Live low, train low – The most common scenario. Use the suggestions in this piece to help you better prepare for your next event at high altitude.

Altitude is like a bee sting—people react to it differently. If your next race is in the mountains, on elevated plateaus, or high deserts, learn how your body responds in these conditions and take the best steps to ensure a successful race.

Call for Comments (from Bryon)

  • Where have you run or raced at altitude. How did your body react?
  • How have you prepared to run or race altitude? What seemed to work or not work well for you?

References

Ian Torrence: has completed more than 200 ultramarathons, with 50+ wins, since his first ultra finish at the 1994 JFK 50 Mile. Ian and his wife, Emily, are online coaches at Sundog Running. Information about his coaching services can be found at SundogRunning.com.

View Comments (47)

  • Hi Guys

    Something I have heard and been told is that if you have a high altitude event, it may be worth spending 2 - 3 nights as high as you can, 14 days before the race.

    This supposedly shcks the body into producing more EPO and red blood cells etc but I am a bit dubious as the bosy will revert to its comfort zone as soon as you go back down?

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  • Excellent article. I just moved from sea level to Boulder, so this article is very timely. I knew about the diuretic effect of altitude, but had never really thought why this should happen, but now I understand. I also had never heard about the glycogen/fatty-acid fuel source effect.

    One little pedantic quibble; gravity is 99.9% (give or take) as strong at 1 mile altitude as it is at sea level, so gravity's pull on air molecules is pretty much equally strong at any terrestrial altitude. Air pressure is really just a function of how much air is above a given molecule; the more air there is above pushing down (due to gravity), the higher the pressure will be. High altitude = less air above = less pressure.

    Sorry, that wasn't relevant, but I can't help myself.

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  • Another great piece, Ian. I like to tell myself that high altitude doesn't affect me but I suffered quite a bit as my Hardrock race dragged out last year ('11). The longer I was out on the course and hitting 13,000+ ft, the more I developed symptoms of HAPE. This year I completed it a bit faster (8hrs), so the effects didn't come into play as much. Oddly, this year I came from 0' elevation in the Bay Area straight to 10k for Hardrock, whereas last year I lived at 6k up to the race date. In a round about way I guess I'm saying that altitude not only affects different people differently but also affects the same individual differently on given occasions. I also go back and forth between 0 and 6,000 ft often, so I may just be used to the changes now. Thanks for the article!

    Tim

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  • Great article! I live in Lyons,co 9 months of the year and 3 months in AK where I'm a commercial fisherman. I always wondered why it was so tough to return to altitude and get my butt kicked the first few weeks of training. I know I loose fitness living on a fishing all summer. I expect to breathe heavy when I return, but the lack of being able to push the legs was always bewildering. So now I know it's not the donuts and beer I consume on the fishing boat.

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  • Words of sage: don't try to run Hardrock three days after spending 65 days straight training below sea level. Or it might have been due to the one of three that I was mostly hungover. ;)

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    • Death Valley or submarine? ;-)

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  • under-water

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    • Ah... Sealab 2021!

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  • I've heard rumors about using sauna/steam rooms to race better at altitude. I've never been able to find much with online searches. Anyone else know anything about it?

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  • What about the reverse situation? That is, if you live high, train high, but are racing at sea level. Is there proper timing involved in returning to sea level to get the most benefit for an event? ...I'm thinking SF December 1st ;-)

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    • You'll feel super human. I'll be back there myself in a couple weeks. Fun times.

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    • Just show up the day before. You should feel pretty good especially at that distance. Hardest part will probably the start since that is when you will most likely be anaerobic. Your legs will feel a bit heavy but come around as the pace drops and mileage increases.

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  • Great article. Coming from a cycling background, the issues are similar. I have done training camps 10-14 days out from a 5-7 day altitude stage race as well as arrived the day before the same race. The best way to know how you will react is to try both. If this isnt possible, then just show up right before. My experience is based over 8yrs of professional cycling and now working as a sports director for a professional team.

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  • I heard that if you travel up the night before and run the next day, the altitude has less effect. I tried it last year from sea level to nearly 7000 feet in the Alps...I felt okay and wasn't aware of any altitude effects...it was only 50k but I wondered if anyone else had tried this or what Ian's opinion might be.

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    • I had the same experience, Phil! Travelling from San Francisco to race in the High Sierras, arriving the night before.

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  • Great info! I have a question. I live at 5300 ft but I'm always racing higher, between 6500-11k. Will the same VO2 Max workouts help prepare me for higher racing? The only time I'm able to get significantly higher during training is on the weekends.

    Thanks,

    Tom

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    • I dont know if the author will chime in here, so I will throw in my thoughts.... Altitude racing is all about aerobic capacity or working at or below lactate threshold. When someone from sea level goes to high altitude, they easily over work their aerobic system ending up anaerobic which we all know cant happen for long, so they have to stop and have all the bad things happen that come with altitude.

      In response to your question, the intervals would help you feel more comfortable working AT threshold. This is a good thing because you want to stay aerobic at the high altitude races maybe only going anaerobic at the start when charging hard over a climb.

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    • Tom,

      I'll add on to what Omer has correctly noted below. VO2 max work will always help you at higher altitudes. Increase your fitness (like your VO2 max) and you'll have a much easier time adjusting to any new environment. Since you'll reach VO2 max much quicker at altitude you'll want to be sure to modify the workouts accordingly - even at the altitude you live at currently - so you can complete a proper workout. Like Omer says, "at altitude they easily over work their aerobic system ending up anaerobic." Once you "go" anaerobic at altitude you'll have a very hard time recovering. So, it might behove you to error on the conservative side when beginning VO2 max work at 5,300'. Test the waters with short repeats and longer recovery periods than what most literature might suggest. Once you get a feel for the work, then you can add more.

      Cheers!

      Ian

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      • Sorry Ian, didnt mean to tread on your turf. Thanks

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        • Omer,

          It's a open forum lad. Discussion is great as Bryon will attest. I claim no turf so tread all you'd like. Thanks for your input.

          Cheers!

          Ian

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  • I raced Bolder Boulder and Great Ethiopian Run in 2010. Boulder was difficult, but GER was impossible. Found it almost impossible to breath (though I'd been training at that height for 8 weeks before hand). Heat was probably also a factor, as I'd been doing my training in the early mornings or late evenings. Just couldn't run any faster. About 2 minutes after the race, I felt like I hadn't raced at all. Never had that feeling before, or since. Ran just outside 50 mins for 10km; have a pb of 38 mins (and think I was close to PB shape). Running back at sealevel was amazing though!

    Good article by the way.

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  • great article. i definitely agree altitude can affect different people differently... and same people differently depending on the day. I would say day 3 is always my worst when switching from sea level to anything above 5,000ft, and I have a difficult time staying hydrated for quite awhile.

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  • Great article Ian, thanks for covering both the positive and the negative/myth side of altitude training. There was a great podcast on Tri Talk a few years back which set out to debunk altitude training and I admit it had some pretty significant claims against it.

    When it comes down to it, altitude training is all in part of an overall plan. I think many people search out that silver bullet and for years, altitude training was it.

    One addition is with regards to racing. The best time to show up for a race is 1-2 days before or a week or more before. Most runners start to feel a distinct decline 3-5 days after arriving. Omer mentions it above.

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  • Great info. Very relevant for me since I live at sea level (well, OK, 150 ft above) but hope to head West next spring/summer for some mountain running. My only experiment was, ironically, my first 50m at Tahoe two years ago. I employed the worst possible strategy, arriving 2-3 days pre-race. Not sure if my feeble efforts to jog/walk for an hour at 7,000+ feet the day before the race helped (I suspect not), but I suffered no altitude sickness and I'm not even sure it slowed me down that much. Of course, Tahoe is not Hardrock, though I recall hiking years ago at 12k and not being affected too terribly. I'm sure there is great individual variability in altitude effects and adaptation.

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  • Hi

    Thx for article. can someone explain WHY arriving night before race ONLY alleviate altitude sickness ? What is the mechanism? cheers

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    • easy answer is that your body doesnt have time to freak out. altitude sickness is a evil beast that really affects everyone if different ways. honestly most people who think they have altitude sickness dont actually have it, they just went way too hard, blew up and with the lack of oxygen couldnt recover.

      when thinking about the "mechanism", I think you look at the symptoms. say its throwing up, could be you are dehydrated or maybe too much water and not enough salt.... another symptom is sleeping terribly, well try breathing with a plastic over head and a penny size hole cut into it. that about sums up sleeping at 10k+ feet. all of this is explained by addressing the symptoms and not thinking that you are just altitude "sick".

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      • Thanks omer however I was thinking about physiological point of view rather than general explanation. Anyone?

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        • wikipedia..... http://en.wikipedia.org/wiki/Altitude_sickness

          Altitude sickness—also known as acute mountain sickness (AMS), altitude illness, hypobaropathy, "The altitude bends", or soroche—is a pathological effect of high altitude on humans, caused by acute exposure to low partial pressure of oxygen at high altitude. It commonly occurs above 2,400 metres (8,000 feet).[1][2] It presents as a collection of nonspecific symptoms, acquired at high altitude or in low air pressure, resembling a case of "flu, carbon monoxide poisoning, or a hangover".[3] It is hard to determine who will be affected by altitude sickness, as there are no specific factors that correlate with a susceptibility to altitude sickness. However, most people can ascend to 2,400 metres (8,000 ft) without difficulty.

          Acute mountain sickness can progress to high altitude pulmonary oedema (HAPO) or high altitude cerebral oedema (HACO), which are potentially fatal.[2][4]

          Chronic mountain sickness, also known as Monge's disease, is a different condition that only occurs after very prolonged exposure to high altitude.[5]

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          • thanks again.Maybe i am being simple but my question is: WHY arriving night before race ONLY alleviate altitude sickness ? i am referring to point 1 of the article" If a sea-level trained athlete travels to a race at elevations above what she is used to, the best course of action is to compete immediately upon arrival." body does not have time to "freak out" is not an explanation of physiological mechanism of point 1 statement.

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          • Hi Pez,

            Reread the Incredible Hulk section of the article again:

            "Immediately upon exposure to higher altitude: Blood plasma, the “water” of our blood, levels decrease rapidly in order to increase the density of red blood cells and oxygen carrying hemoglobin being pumped through the circulatory system. Due to this initial drop in plasma, stroke volume (the amount of liquid pushed through the heart) decreases, and in turn heart rate increases to compensate."

            If you can get your race finished before this process is completed you'll be better off.

            Cheers!

            Ian

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  • +1

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  • Great article! Wish this had been published a few months before I got my buttocks kicked at Speedgoat this year! Now I know what I did wrong - figured I'd be moving slow so I did few VO2 workouts, got there 3 days before due to a business trip (live in Upstate NY elevation 700 ft, business trip to San Fran). And yep - felt like I was running through wet cement. Thanks for the insight Ian. Maybe I'll give it another go in 2013 but now I'll be a little better prepared for the altitude.

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  • People will laugh but my first taste of altitude was embarassing. 3500 feet. At first I thought it was the heat during summer which made no sense since I'm very heat tolerant in exercise being from the south. Then it happened to me again a couple months later on the same hike when it was much cooler. There's so much individual variability in altitude adjustment, as I have trouble if I start hiking 3000 feet above my baseline altitude out the car without fail whereas if I sleep on it a day I'm much better. But too long then I start getting the periodic breathing during sleep and physiological changes after 3 days and you don't really feel like your old self again in exercise until after 2-3 weeks. I even have a much shorter (a day or two) but still there adjustment period coming down from altitude. You can almost say altitude is like allergies, some people get it and some people don't and then they proceed to make fun of those that do as being soft :) I wouldn't have traded any of my altitude stints though as there's something about living and doing vertical in thin air that left a permanent stamina gift in my legs. To each his own.

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  • Great article! I got to do my first real altitude running this summer out in CO and experienced a lot of what the article talks about. I definitely believe it would be an advantage to be able to live and train at altitude.

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