The effect of hyperventilation-induced hypocapnic alkalosis (Hypo) on the adjustment of
pulmonary O2 uptake (V̇o2p) and leg femoral conduit artery (“bulk”) blood flow (LBF)
during moderate-intensity exercise (Mod) was examined in eight young male adults.
Subjects completed four to six repetitions of alternate-leg knee-extension exercise during
normal breathing [Con; end-tidal partial pressure of CO2 (PetCO2)∼ 40 mmHg] and
sustained hyperventilation (Hypo; PetCO2∼ 20 mmHg). Increases in work rate were made …

New findings• What is the central question of this study? Voluntary hyperventilation that
induces hypocapnic alkalosis (HYPO) is associated with slowed adaptation of O2 uptake
and leg blood flow during moderate exercise; however, it is unknown whether hypocapnia,
alkalosis and/or the hyperventilation manoeuvre is related to these observations.• What is
the main finding and its importance? We included a condition with the same work of
breathing as HYPO, but the fall in CO2 was prevented by the addition of higher CO2 to the …