A second, more aggressive approach, which is called carbon monoxide inhalation and uses the same equipment and techniques, steps into the scientifically new and much riskier realm of inhaling the poisonous gas for the express purpose of performance enhancement. A growing body of recent scientific research suggests CO inhalation can have a powerful impact on measures of aerobic capacity like VO2max, or maximal oxygen uptake.
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By inducing hypoxia – a state of oxygen deprivation – CO inhalation can be used to prolong or even replace the performance-enhancing benefits of altitude training. It can also be used in conjunction with altitude training to maximise gains, as part of an approach called “super altitude.”
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The technique is not banned by WADA, although it appears to conflict with the agency’s rules around artificial manipulation of the blood. And there is no hard evidence that any WorldTeams are currently using CO inhalation for performance gains. But
