Today many competitive endurance athletes practice a training philosophy known as “Live High, Train Low.” They sleep in an oxygen-poor environment (mimicking the high altitude environment) to thicken their blood, but they train at low altitude to maximize their training performance and the benefits they derive from it. Some do this the hard way, by making their homes in the mountains and going downhill for important workouts, while others have turned to technology to make the process a bit more convenient. Altitude tents simulate high altitude by creating a hypoxic environment, reducing the oxygen content of the air inside the tent.

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