Respiratory Muscle Strength Training in Presbyphonia

IMST will be conducted using an inspiratory pressure threshold trainer (Philips Respironics® Threshold IMT or POWERbreathe® Medic Plus), which consists of a mouthpiece with a spring-loaded valve. The valve blocks the airflow until the threshold pressure is achieved by breathing in forcefully into the device. This allows airflow as long as the sufficient pressure is maintained.

EMST will be conducted using an expiratory pressure threshold trainer (EMST150®), which consists of a mouthpiece with a spring-loaded valve. The valve blocks the airflow until the threshold pressure is achieved by breathing out forcefully into the device. This allows airflow as long as the sufficient pressure is maintained.

Voice exercises will consist of the Vocal Function Exercises (VFE) protocol, developed by Stemple (2005). It contains 4 steps: (a) sustain the vowel /i/ on the musical note F for as long as possible. Repeat as judged by the SLP. (b) Glide from the lowest note to the highest note. Repeat as judged by the SLP. (c) Glide from the highest note to the lowest note. Repeat as judged by the SLP. (d) Sustain the notes C-D-E-F-G for as long as possible. Each note will be repeated until the participant finds the right placement (forward-focused voice), as judged by the SLP. Humming will be used to facilitate placement.