By Carl Valle
In the decades since the 1968 Olympics, we have seen a huge amount of resources spent training at altitude. For the most part, endurance athletes seem to get a benefit from it, ranging from a theoretical 1% difference, to as high as 3%. Team sports, such as soccer and rugby, have experimented with training camps to get the benefits of living high, but others have stayed home for good reason.
The market explosion of altitude tents, hypoxic chambers, and even the altitude training mask are signs that the average Joe values replicating elevation. Altitude may be the difference maker for some athletes, but it could be a catastrophe for others. In this article, I cover the realities and practical points of training at altitude, and what to prepare for if you plan to take a trip to a more elevated destination.
Who Can Benefit from This Article
This piece is nothing more than a summary of plenty of scientific papers available on Researchgate or Google Scholar. I can’t give you anything besides an honest assessment of my experience with athletes training at elevation, and the reason is the science is still in its early days for athletes who are not endurance competitors. If you are a sport scientist, coach, or an athlete, this article can give you a fresh perspective or new insight. Even if you are a recreational athlete and are traveling, it’s worth reading.
This is not a how-to article—it’s a straightforward reflection on the last decade of information available, and should answer the following questions:
- How long do I need to live and train at altitude to get benefits?
- What should I do differently while I am at altitude?
- When is it not a good idea to train at elevation?
- Who should avoid altitude training and think about other options?
Most of the questions are logistical in nature, as plenty of coaches want to train at elevation but organizing a training camp can be an ordeal. Some performance coaches want to know about traveling during the competitive season, such as teams visiting Denver or maybe Salt Lake City. That question is more art than science for now, but the New England Patriots decided to be at altitude for a week before their game against the Raiders when they played in Mexico City.
What Happens to the Body at Elevation
When the body is exposed to elevation, physiologically the brain and other organ systems respond almost immediately by increasing erythropoietin, a hormone that stimulates red blood cell production. After about a week, the rise in hemoglobin increases to the point it can actually improve performance for a short period of time when the athlete returns back to near sea level. Longer periods of training and living at high altitude will improve the oxygen-carrying capacity of an athlete’s blood even more, but the amount varies by individual.
During the same time, the body’s iron stores, or ferritin levels, are stressed, and sometimes we see hematological changes that are far from ideal. If athletes are not sufficiently prepared for a training camp and are slightly anemic, they can come back crippled physiologically. Some athletes, especially females on vegan diets who don’t supplement, can ruin seasons with a training camp. It’s not that training at altitude is dangerous and should be avoided, it’s just that you need to have the right resources in place before exposure to any environment that stresses the body.
Another issue with elevation is that you must alter hydration and diet, as the resources needed for the same training load are higher, especially if you increase the training to challenge the body. Additionally, due to the strain on the body, some athletes risk immunosuppression and can get sick from the combination of training hard and living at altitude. Generally, the goal is to challenge the body aerobically, and maintain speed so the athlete isn’t dull when they come back down to sea level.
Athletes sometimes use a training camp to help with peaking, while others try to develop a base so they can train harder in their next preparation phase. Remember, the effects of training at elevation will wear off, but it’s unknown if an athlete can find natural ways to extend this past the windows of adaptation theorized by endurance scientists.
Terminology and Elevation Standards
In the past, training at altitude used to be a short period of time preparing for a big competition, but now it’s far more complicated and terminology can get confusing. Altitude is about elevation above sea level, and most coastal cities are considered near zero in elevation. For every 500 meters above sea level, small changes in the human physiology can occur, but the magic usually starts at 1,800-2,000 meters up, and 2,000-3,000 is a sweet spot for ideal conditioning. In fact, most large cities are closer to sea level than at elevation, and looking at the coasts, you can see that the human population loves the ocean. Peru is home to the highest city in the world, but China has the majority of the top positions in elevation.
Here comes the tricky part. Living at altitude doesn’t mean you have to actually be located in a city that is at a high elevation. Athletes can sleep in altitude and even live in houses that simulate hypoxic conditions. So, in theory, an athlete can live at simulated elevation but train outside or indoors near sea level, and this is called Live High Train Low (LHTL).
Of course, some athletes still practice the old-school LHTH or Live High Train High approach entailing relocation for a short period of time if necessary to induce physical changes. Progressive coaches and athletes use other combinations like Live High and Train Low and High, or Live High and Train Low in the Heat, but we do not know much about how well those approaches truly work.
Types of Responders to Altitude and Genetics
The most important takeaway from this article is that everyone is different, but not that different. My biggest complaint in sports is that we treat everyone like either a clone or the other side of the extreme—we prepare athletes with too much personalization with the expectation that those small differences will make a real change. I do believe that the little things can add up the spectacular, but marginal gains only work when the major priorities are in place.
Training at altitude is the rare exception for me, as it represents an occasion when, if you don’t personalize, you could be in some serious trouble. It’s fine to overthink things once in a while and not see any benefit, but if the decision to lump athletes into groups without profiling the details causes injury, illness, or a loss in performance, a coach needs to take the blame.Unlike some other areas of athletic development, you need personalization with training at altitude. Click To Tweet
Instead of waiting to talk about athletes who should not go to altitude training camps, I should have placed the discussion first, for good reason. Athletes who are iron-deficient—a significant population, as a matter of fact—should stay home. The variability in results with training camps is due to the fact some athletes actually come home impaired further in regard to red blood cell production, and could come back anemic.
An easy way to prevent anemia is to periodically screen the blood and focus on iron stores, not hemoglobin or other indices. As athletes train, blood parameters like plasma volume increase, so false positives of anemia can occur. Detailed training records and simple blood tests may be enough to screen properly, but if you want to know whether athletes can actually transport more oxygen precisely, they need to do lab testing.
Athletes known to get sick easily and who don’t have a resilient or robust immune system could be a poor fit for altitude. Stress is stress, and training at elevation could put an athlete who is fragile out of commission. Inflammation to the body is also something to consider, as a lot of athletes who don’t manage their internal information sometimes respond negatively to training at altitude.
In general, overtraining symptoms occur when the load is beyond an athlete’s ability to manage inflammation, and soreness and mood responses can be a real problem. While some athletes get a great endorphin response, others comment that they lose that response at altitude. Most of the research on altitude has trouble blinding an athlete from knowing whether they are elevated or not, so placebos are always going to be an issue with the research.
Genetics are interesting, and for the most part, it’s less about ethnicity and more about fiber type and physiology. On the other hand, endurance athletes benefit less than recreational level athletes because they tend to be better prepared and near their ceiling, so team sport athletes might be a good fit if the organizers are smart and have done their homework. It’s recommended that athletes have their blood tested two weeks in advance of a training camp at altitude, but I prefer doing it much earlier so that there is enough time to change iron status if necessary.
Some athletes are stubborn and simply don’t change very much, even if you do everything correctly, such as nutrition and training. Others seem to have dramatic changes. However, as usual, both extreme responses to altitude are outliers. For most athletes, it’s nearly a linear response, and you can see them getting exposure incrementally while training over weeks.
Training Camp Duration – How Long Is Sufficient?
Most mature athletes will get a boost in performance from a week to 10 days of altitude exposure, and some team sport athletes will respond similarly. If you are an elite athlete, two to three weeks is usually long enough to trigger changes that can be seen in the lab, but they are minimal. Elite athletes should stay as long as possible, as four weeks is when you see a change that you can actually use as an advantage.
Again, the longer the better, but don’t stay too long because after the benefits saturate and then wane, speed becomes more of a priority and you eventually need to change the program. Some athletes who live at altitude have no advantage if they attend camps repeatedly; therefore, the decision to live at altitude is about convenience.
Some athletes are “high responders” and may leave within a few weeks, while some stay longer than a month because their hemotoxic profile is slower to change. The difficult aspect of looking at altitude is measuring true red cell production and hemoglobin. Hemoglobin is what binds the oxygen to the top of the red blood cell, and the amount that exists in total in the body is known as total hemoglobin mass (tHb-mass). The only way to really know if tHb-mass has improved is by using a gas analysis test called C02 rebreathing analysis.
If athletes see enough changes to their tHb-mass, most fly back home. In team situations, it’s fine to allow return travel to be individualized as a happy athlete means they may benefit more from getting back home. While altitude sickness is common, homesickness is more likely, especially for athletes who train on their own most of the time.
Athletes that can’t do a training camp and have to compromise on the benefits can use tents and living zones that simulate altitude, but this can mean uncomfortable sleeping at night or cabin fever causing living at home to feel like prison. Some athletes don’t mind making the sacrifice as winning or improvement means everything to the dedicated, but it’s not for everyone. Because of travel, team sport athletes tend to do, at most, a camp, and very few team sport athletes take the next step with hypoxia simulation for home living.
Program Changes to Consider When Simulating or Living at Altitude
Most of the rules still apply to training when an athlete is trying to take advantage of elevation, but a few caveats exist. The primary issue with elevation is that the output at the same intensity is usually lower. While elevation can help maximal performance such as jumps and sprints, it usually compromises endurance. Repeated speed in team sports is compromised, as researchers noted that in 2010, the altitude affected the total distance covered in the World Cup.The real advantage is that athletes live high but train normally, not harder or faster. Click To Tweet
As with warm weather camps and speed athletes, endurance athletes should not fall prey to the mindset that doing something special during a short period of time will make them better. Sometimes regular workouts that are slightly cautious or conservative do more than attempts to make a dramatic improvement in a short period of time. The success of a training camp is the accumulation of total days of work done right, rather than something done different or harder. In fact, the real advantage is that athletes live high but train normally, not harder or faster. Training low or training high is about getting the same work done but with a boost from elevation.
A few changes may be necessary, like additional fueling strategies or iron supplementation, but most of the training alterations are about getting value out of the time at altitude. If coaches want more red blood cells, focusing on aerobic workouts is the name of the game. Maintaining speed and power qualities is a priority though, so abandoning intensity is foolish as it only leaves a team or athlete fit but not fast. Power is known to drop at altitude, but not if rest is adequate and sessions are intense. The adjustment shouldn’t be radical, just enough to ensure the athlete doesn’t regress in speed and also builds capacity to finish strong and pace aggressively.
When Altitude Can Backfire or Fail to Help
Two areas that are poor times to train high are early periods in the season and during the break after a long season. When I see teams using altitude to prime their “energy systems,” I roll my eyes and watch how the back half of their season and the end minutes of games don’t improve. It’s far more important to focus on strength training and the recovery from it than squeeze out a phantom percentage point. The great benefit about strength training is that it’s a year-round gift that sometimes keeps giving, as intermediate and lower-level athletes may actually get stronger during the season. Altitude is like a slow leak—it will help early, but wear off eventually.
Another growing problem is the rise in hippie training. A few years ago, athletes were going on low-carbohydrate diets, usually low-calorie as well, resulting in muscle wasting and poor nutritional status biochemically. Some athletes experiment with plant-based diets and, while a few succeed being vegan, some struggle and are forced to revert back. Now there’s a new thing happening in sport: athletes combining off-season periods of living up in the mountains with restricted diets—a combination that spells disaster. While after a year of competing it’s nice to find or build spirituality, hiking the mountains while eating only kale and avocados leads to a dead end when it’s time to get stronger and be prepared for the rigors of professional sport.Altitude is like a slow leak—it will help early, but wear off eventually. Click To Tweet
Some athletes in Olympic sport will try to build last-minute aerobic capacity before a major international competition to fix a bad training season. An injury or a period of overtraining sometimes derails an otherwise good plan, so coaches and/or athletes overcompensate with Hail Mary approaches like altitude training. Usually, what happens is a crap shoot at best, and when athletes come in tired from both travel and heavy training, the benefits cancel out, or worse.
Be Prepared if You Want to Maximize Training at Altitude
Utilizing a training camp or relocating to another city for the altitude advantage can make or break an athlete, so be prepared long before you travel. Not everyone is a good candidate for elevation, and some athletes should just focus on other factors to get better at their sport. Most teams should reconsider training camps at elevation, as they usually try to combine pre-season fitness and cram in too much training in a bad environment.
Athletes tend to be notoriously ill-prepared early, and if they have injuries, elevation isn’t going to be a great idea. However, experimenting with altitude, in any of its modern forms, is worth exploring if aerobic capacity matters.