the immediate responses to loading were decreases in tidal volume ( vt ) , breathing frequency ( f ) , and minute ventilation ( ve ) , with no difference between wakefulness and stage 2 and stage 3/4 sleep in the effects of loading on vt and ve , but f fell more during wakefulness than during sleep ( p less than 0.05 ) because of a greater lengthening of inspired time ( ti ) ( p less than 0.05 ) .
C0035203
breathing
C0004048
inspired