Changes in Glottal Source Parameter Values with Light to Moderate Physical Load

Engaging in everyday physical activities, like walking, initiates physiological processes that also affect parts of the body used for speech. However, it is currently unclear to what extent such activities affect phonatory processes, and in turn, the voice. The present exploratory study investigates how selected glottal source parameters are affected by light and moderate physical activity. Recordings of sustained vowel /a/ were obtained from 39 female speakers of German at rest, and during low-intensity and moderate-intensity cycling. Ten glottal source parameters thought to reflect different physiological states were investigated using VoiceSauce. Even during light activity, significant increases were found in f0, strength of excitation and H1, and a decrease in harmonics-tonoise ratio at higher frequencies. During moderate-intensity activity, significant effects were stronger and found for most parameters. However, considerable intraand interspeaker variability was observed. These findings may be relevant for applications in automatic speaker-state recognition. They also underscore the importance of investigating individual-level responses to better understand stress–voice interactions.