By Teemu Virtanen

There has been a lot of discussions about high altitude training and its benefits, and drawbacks as well, due to the fact that the upcoming winter Olympics take place quite high above sea level. Additionally, many Visma Ski Classics events are organized at high altitude, which means that our Pro Team athletes need to be able to race well in such conditions if they want to succeed in the Champion competition.

Therefore, let’s take a look at high altitude training and what it really constitutes of. Generally speaking, high altitude is defined as any elevation above 1,500 meters, and high altitude training as a method started around the time of the Olympics in Mexico City in 1968, which took place at an elevation of 2,240 meters above sea level.

High altitude training is the practice of exercising for several weeks at high altitude, the elevation varies depending on the athlete´s preference. At high altitude, the body acclimates to the relative lack of oxygen in several ways such as increasing the mass of red blood cells and hemoglobin or altering muscle metabolism.

By training at high altitudes, athletes aim to allow their bodies to produce extra red blood cells. Then, they head to a competition at lower elevations to take advantage of their changed physiology, which should last for 10 to 20 days. Some athletes prefer to stay in high altitude for a long time, but the risk of that approach is that their training may suffer due to less available oxygen for workouts.

This method is often used when a race takes place at high altitude so that athletes can adapt to the demands of the elevation. The stimulus on the body is then constant because the athlete is continuously in a hypoxic environment. Initially VO₂ max drops considerably: by around 7% for every 1000 m above sea level at high altitudes, and oxygen metabolism decreases.

“Most endurance sports elite athletes use high altitude training in their pre-camps before important World Championships, in cycling, running, cross-country skiing, rowing, swimming and many other sports,” Magnar Dalen, the director of Team Ragde Charge, says about the commonly used training method. “The effect in building more red blood cells is the aim, and it’s a proven fact. But I think the psychological benefit is equally important. To go to these places where you can really just focus on training, eating and sleeping.”

Perhaps, the most common training regime is the “live high and train low” principle. This training idea involves living at higher altitudes in order to experience the physiological adaptations that occur, such as increased erythropoietin (EPO) levels, increased red blood cell levels, and higher VO₂ max while maintaining the same exercise intensity during training at sea level. EPO stimulates red blood cell production from bone marrow in order to increase hemoglobin saturation and oxygen delivery.

Based on the assumption that the altitude training stimulates a more efficient use of oxygen by the muscles, many athletes live high, train with low intensity in high altitude and do their most demanding sprints and intensive workouts at lower elevation. This is a typical method for the early fall ski camps where our athletes train on snow in the morning and do another workout at lower elevation such as running or roller-skiing. Usually, the second workout is much higher in intensity.

Not everyone is convinced that high altitude training is a “must-do” method for skiers. The adaptation and the benefits that one can get from training in high elevation are very individual in nature. Vetle Thyli, the captain of Team Kaffebryggeriet, says that he does not find high altitude training absolutely crucial for gaining success in long distance skiing.

“Personally, I’m not sure how much better I can perform with or without high altitude acclimatization since I’ve performed at the same level regardless of the altitude. I have both the best and worst kind of experiences. High altitude training is not something I focus on. In order to get any significant results of it, you need to do it a lot, and I just can’t afford it. I don’t think the extra training effect is that remarkable because I can’t train as hard as I can in lower altitudes. Overall, my philosophy is to keep travel days at the minimum, stay healthy and save energy for efficient training.”

Vetle’s point is shared with many other athletes, but altitude training remains very popular. It works because of the difference in atmospheric pressure between sea level and high altitude. At sea level, air is denser and there are more molecules of gas per liter of air. Regardless of altitude, air is composed of 21% oxygen and 78% nitrogen. As the altitude increases, the pressure exerted by these gases decreases. Therefore, there are fewer molecules per unit volume: this causes a decrease in partial pressures of gases in the body, which elicits a variety of physiological changes in the body that occur at high altitude.