Training at high altitudes has been popular among runners since the 1968 Olympics in Mexico City. From the results of those Games it was obvious that to compete well at high altitude it is necessary to train at high altitude. It is not clear, however, whether training at altitude provides an advantage for competitions at sea level. The few well-controlled studies have found mixed results when athletes train at altitude to prepare for sea level races. Yet, places such as Boulder, Colorado, and Albuquerque, New Mexico are practically shoulder-to-shoulder with world-class athletes and wannabes seeking the high altitude edge. Let’s take a look at the physiological effects of altitude training and the latest ideas on how to improve your performance with high altitude.
The primary benefit of altitude training is an increase in the natural production of the hormone erythropoietin (EPO), which increases the hemoglobin content of your blood. Oxygen is transported in your blood attached to hemoglobin. An increase in EPO, therefore, leads to an increase in the oxygen carrying capacity of your blood, which lets more oxygen reach your muscles allowing you to maintain a faster pace. The downside to training at high altitude, however, is that due to the thin air you cannot train as intensely as at sea level. Less intense training produces a less fit athlete, which is why studies of athletes training at altitude to compete at sea level have had inconsistent results.
To provide the best of both worlds, therefore, you should live at high altitude (live high) and come down the mountain to do high intensity training at a lower altitude (train low). In this way, your body increases red blood cell production, but you are able to maintain high intensity training. Several recent studies have found performance benefits from the live high/train low method. The problem with living high and training low, however, is that it can be a logistical nightmare. There are only a few places in the world where you can live at a high altitude and quickly drive down to low altitude to work out. Sensing a potential market, entrepreneurs have recently developed a variety of ingenious altitude simulators that “bring the mountain to you” by creating artificial high altitude environments.
Altitude Option Increases Red Blood Cells? Able to train at high intensity?
Live High/Train Low Yes Yes
Live High/Train High Yes No
Live Low/Train High Possibly No
There are at least 5 different altitude simulators currently available, which fall into 3 categories (see table below). Nitrogen houses are complete living areas sealed off and brought to a low oxygen concentration. You live and sleep in these houses, and train outside at sea level. Altitude tents are a less-expensive and more portable alternative, in which you set up a sealed tent over a standard bed and sleep at simulated high altitude. Both of these methods mimic the live high and train low scenario.
Another option is the hypoxic (low oxygen) training chamber. This is a sealed room in which you work out at simulated high altitude. Hypoxic chambers are springing up in fitness centers around the U.S. This system is really the opposite of live high and train low in that you train at simulated altitude and live at sea level. This runs counter to the popular hypothesis that the gains in red cell mass are realized by simply living at altitude while performance gains require high intensity training. Here at the lab, we tested a hypoxic chamber for 3 weeks. We put in a rowing machine and a turbotrainer, and cranked it up to 8,000 feet. With air conditioning and a humidifier, training in the chamber was quite comfortable, but also boring as hell.
The final alternative to increase red blood cell count through altitude simulation is “intermittent hypoxic training” or high altitude intervals. Using a hypoxicator or similar device, you breath air at the equivalent of 22,000 feet altitude for 5 minutes, and then breath regular air for 5 minutes, and repeat these “hypoxic intervals” for 1 hour. We tried the hypoxicator for 3 weeks with several of the world’s best triathletes and a 27:44 10,000 meter runner and found increases in hemoglobin and hematocrit of 1 to 4%.
Interestingly, there was wide variation between athletes both in how they felt using the hypoxicator and in how they responded physiologically. A recent study by Dr. Benjamin Levine and colleagues, published in the Journal of Applied Physiology, found similar differences between subjects in the response to altitude training. Athletes who do not respond to altitude training are thought to have a reduced EPO response, which is not enough to increase red blood cell production.
Type Method Scenario
Nitrogen House Live and sleep at high altitude Live High/Train Low
Altitude Tent Sleep at high altitude Live High/Train Low
Hypoxic Chamber High altitude training in sealed room Live Low/Train High Hypoxicator Intermittent breathing Live Very High
at very high altitude and Low/Train Low
Altitude training typically leads to performance improvements of 1-3%. So, before investing in an altitude simulator, make sure you have a good coach and have put in several years of well-planned training. At that point, the extra 1-3% could be the difference between making the Olympic team, or staying home and watching the Games on TV.
This article is a contribution from Peter Dickson Pfitzinger, an American former distance runner, who later became an author and exercise physiologist. He is best known for his accomplishments in the marathon, an event in which he represented the United States in two Summer Olympic Games: the Los Angeles Olympics and the 1988 Seoul Olympics.