Expiratory Muscle Strength Training: Effects on Speech and Cough Production

S Baker, C Sapienza, P Davenport


Reduced expiratory muscle strength compromises the necessary lung pressure for speech and cough production.  It is known that expiratory muscle strength can be increased with strength training programs.  A few studies provide reports of improved speech and cough following an expiratory muscle strength training program (EMST).  The majority of the reports are subjective, with little information regarding physiologic changes that occur with EMST.  Participants in this study were 16 healthy male and females; average age of 25.2 years.  These participants completed an eight-week EMST program, five days per week.  Maximum expiratory pressure (MEP) was the measure of maximum expiratory muscle strength and was obtained at baseline and after each week of training as well as at four weeks and eight-weeks post-training.  Speech measures included intraoral pressure, subglottal pressure, and peak RMS.  Cough measures included maximum flow rate, compression time, and rise time.  The results revealed a significant increase in MEP and peak RMS as well as a significant decrease in the ratio of intraoral pressure to MEP and compression time (p <.05).  Increased input to subglottal pressure receptors with increased expiratory muscle strength is hypothesized to decrease the compression time during cough production.