Our bodies are fine-tuned machines that combust fuel (food) in a chemical reaction with oxygen (derived from the atmosphere we breathe) to generate energy. If we don’t eat, we will find our bodies weaker, unable to generate energy without fuel. And of course if we don’t breathe, or if we reduce the concentration of oxygen that we breathe, we will also find it more difficult to generate energy.
At higher altitudes, the atmosphere is thinner, and so it is more difficult to perform strenuous activities. Even everyday exhertion, like a brisk walk, can prove difficult for a person who has just arrived in a high altitude location from a low altitude origin.
This presents athletes with an opportunity to supercharge their cardiovascular systems. By training at high altitudes, where oxygen is scarce, they can improve their body’s ability to extract performance out of smaller amounts of oxygen. When they return to lower altitudes, they will experience a respiratory boost, and be in better condition than athletes who have engaged in comparable training at a low altitude.
