inspiratory reserve volume

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(physiology) The amount of air that can be inhaled by forcible inspiration after completion of a normal inspiration.

(complemental air), the maximum volume that can be inspired from the end of tidal inspiration

Maximum volume of air inspired from the end of an unforced inspiration. The inspiratory reserve volume decreases during exercise.

(Abbr. IRV) The maximal volume of air that can be inhaled after a normal inspiration. Also called complemental air.