seven sea level resident males , aged 22 +/- 1 yr , performed moderate to near-maximal steady-state cycle exercise at sea level in normoxia [ inspired po2 ( pio2 ) 150 torr ] and acute hypobaric hypoxia ( barometric pressure , 445 torr ; pio2 , 83 torr ) , and after 18 days ' residence on pikes peak ( 4,300 m ) while breathing ambient air ( pio2 , 86 torr ) and air similar to that at sea level ( 35 % o2 , pio2 , 144 torr ) .
C0004048
inspired
C0035203
breathing