Indeed, it is well known that women typically havesmaller lung volumes and maximal expiratory flow rates(Fig. 1) even when corrected for standing height (as asurrogate for chest volume) relative to men (13). Althoughwe have made the case for sex-based differences inpulmonary structure and resting pulmonary function, thequestion germane to this review is the following: do theseFigure 1. TLC. When matched for TLC, tracheal area as measured by airway area acoustic reflectance.