Characteristics of speech breathing in young women.

Chest wall kinematic records were obtained from 10 healthy young women in the upright, seated position during resting breathing, conversation, and reading aloud. Breathing frequency, lung volume levels relative to resting end-expiratory level, and relative volume displacements of the rib cage and abdomen were measured. Compared to conversation, group results for reading revealed three differences: an increase in syllables spoken per breath, an absence of filled pauses, and a slight upward shift in end-inspiratory and end-expiratory lung volume levels. Compared to resting breathing, group results for speech revealed four differences: a background chest wall configuration characterized by a relatively larger rib cage and smaller abdomen, slight increases in breathing frequency and in lung volume expenditure, and a slight decrease in rib cage contribution to lung volume displacement. The physical characteristic most strongly associated with rib cage contribution to lung volume displacement in resting breathing was height (r = .76). In comparing the relationship between the same respiratory behavior during resting breathing and speech, a correlation of .83 was obtained for rib cage contribution to volume displacement in the two conditions and of .60 for end-inspiratory volume level in the two conditions. Somewhat weaker positive correlations were obtained for lung volume expenditure and for breathing frequency in the two conditions. Comparison of the present findings for women to those recently reported for comparable men (Hoit & Hixon, 1987) revealed no remarkable differences in speech breathing characteristics. Results suggest that certain physical characteristics and task variables may have greater functional importance than gender in determining normative speech breathing behaviors.