the purpose of these experiments was to compare the effects of breathing air ( 79 % n2-21 % o2 ) and a normoxic helium oxygen gas mixture ( he-o2 ) ( 79 % he-21 % o2 ) on maximal oxygen uptake ( vo2 max ) and work tolerance during both incremental and high-intensity constant load exercise .
C1875235
helium oxygen gas
C0030054
o2