The paper doesn't discuss the physiological mechanism by which poor air quality impairs performance. Perhaps the idea just that a higher ppCO2 impairs CO2 excre

The paper doesn't discuss the physiological mechanism by which poor air quality impairs performance. Perhaps the idea just that a higher ppCO2 impairs CO2 excretion, creating back pressure against all aerobic metabolism. If so this raises some interesting questions: Could we achieve "superhuman" performance by breathing CO2 depleted air (below ~420 ppm)? Is the rising atmospheric CO2 level making us all stupider? Should teachers begin class with a breathing exercise?