Jason Tremblay – PFT Certificate
Growing up in the heart of the Rocky Mountains in Alberta, I have always been aware that famous athletes were coming here to train before major competitions. However, I could not figure out why these world-class athletes kept coming to the Rocky Mountains to train.
Training in unique environmental conditions such as altitude training, was initially researched at the Harvard Fatigue Laboratory by David Bruce Dill. The ability of the human body to adapt to different circumstances is fascinating to say the least. Once research became clearer on the topic of altitude training, coaches have clamored to find ways to harness the benefit of high altitude training to help their athletes in competition.
The Theory behind High Altitude Training
At sea level, the air contains 20.9% of oxygen gas. As altitude elevates, the percentage of oxygen and the barometric pressure of the air decreases. To compensate for the lower partial pressure of oxygen, the body adapts. When being exposed to higher altitudes the first thing that happens is respiratory rate and heart rate increase.
After the initial adaptations, these longer-term changes begin to take place:
- Increase in the number of mitochondria and oxidative enzymes.
- A chemical change within red blood cells that makes them more efficient at unloading oxygen at the capillary beds.
- Excretion of base to restore pH balance through kidneys.
- Increase in the number of red blood cells.
The idea of training at high altitude is to get these adaptations to occur right before a major competition that will be held at a lower altitude. The thought process behind this is that the body will be more efficient at O2 transport due to the adaptations from high altitude. When the partial pressure of oxygen is higher at low altitude, the athlete will have a competitive advantage because of increases in red blood cell count, mitochondria and oxidative enzymes.
What does the science say about high altitude training?
In a study published in the Journal of Applied Physiology in 1996, a research group set out to determine the effect of moderate-altitude acclimatization with low altitude training on performance.
- The study tested the hypothesis of “living high and training low” by organizing 39 competitive runners into three separate groups.
- The “high-low” group lived at a moderate altitude (2500 m) and trained at a low altitude (1250 m).
- The “high-high” group lived and trained at a moderate altitude of (2500 m).
- The “low-low” group lived and trained at a low altitude (1250 m).
- After a 4-week training period, both high altitude groups significantly increased VO2 max (5%) in direct proportion to an increase in red blood cell volume (9%). Neither of which changed in the “low-low” group.
- Velocity at VO2 max and maximum steady state also increased only in the “high-low group”.
- The results of this study conclude that living and training at high altitude for a four-week period before competition at low altitude improves performance in competitive runners.
Administrative Concerns
During high altitude training, both the coach and athlete must be aware of hypoxia. Hypoxia is a condition in which there is inadequate supply of oxygen to the body. Hypoxemic hypoxia is caused by low partial pressure of oxygen in arterial blood. There are numerous physiological and environmental factors that lead to hypoxia, one of which is low partial pressure of atmospheric oxygen, which occurs at high altitude. If training altitude is initially too high or intensity (% of HR max) of the training session is too much, the athlete may begin to experience hypoxia. The symptoms of hypoxia include headaches, fatigue, shortness of breath, euphoria, nausea, and changes in level of consciousness. In severe cases hypoxia can cause seizures, coma and death.
*Effect of hypoxia on basic neurological function.
Intermittent Hypoxic Training
Due to the popularization of altitude training amongst aerobic athletes, it was proposed that training at hypoxia while living in normoxia could potentially enhance athletic performance.
In 2010, a research group set out to determine if hypoxia training was good for muscles and exercise performance.
- Subjects trained in hypoxia and live in normoxia.
- Available performance capacity data suggests that intermittent hypoxic training is not consistently found to be advantageous for endurance performance at sea level.
- Further research is needed in the topic
- Risk vs. Benefit?
In conclusion, training at high altitude has been proven to be an effective means of increasing aerobic performance at sea level.
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