[Respiratory mechanics in professional flautists]

Oesophageal, gastric, mouth, transdiaphragmatic, transpulmonary pressures, diaphragmatic EMG, sound and chest wall excursion were measured directly in 3 professional flautists whilst playing their instruments to determine: - what respiratory muscles and percent vital capacity were being used; - how mouth pressure, embouchure resistance, embouchure aperture, airflow and velocity affect sound loudness and frequency. Lung volume was estimated from transpulmonary pressure during playing and the static deflation pressure-volume curve was measured separately; flow was calculated from delta volume/delta time; embouchure resistance was calculated from mouth pressure/flow; velocity was calculated using Bernouilli's equation and mouth pressure. Staccati and sustained tones at different frequency and intensity were performed. Sound loudness was mainly related to airflow whilst sound frequency was determined by velocity. Flow and velocity were independently controlled by mouth pressure and embouchure aperture. Mean mouth pressures varied little from individual to an other (6-11 cm H(2)O) but the flautists used between 72-83% of their vital capacity suggesting inspiratory muscle activity while playing. However, rib cage and abdominal motion were different for each subject. Although different flautists use different strategies to control mouth pressure, their individual mastery of the instrument permits control of airflow and velocity to produce the desired intensity and frequency of sound.