Teachers' Working Postures and Their Effects on the Voice.

OBJECTIVE: To evaluate associations between voice and working postures used during teaching.

METHODS: A researcher assessed 30 teachers' typical working postures of the torso, head, shoulders, upper back, and arms by observing and/or asking questions about them. Teachers' options to rest and to adjust furniture according to their needs were also elicited. Voice symptoms were evaluated through 2 self-assessment forms. Fundamental frequency, sound pressure level (SPL), and alpha ratio were calculated from voice samples recorded before, during, and after teaching.

RESULTS: The head was most typically in an unergonomic posture while speaking (in 60% of participants). Other frequently used unergonomic postures were hunched upper back (55%), raised shoulders (46%), and twisted torso (43%). Head and torso twisted and arms upheld were associated with specific voice symptoms and head postures and hunched upper back with voice use. The number of postures was also connected with voice use: if the teachers used over 3 unergonomic postures, their SPL was higher and the voice broke more often than in those with a lower number of postures.

CONCLUSION: Unergonomic postures during speaking affect the voice. It is important to evaluate working postures as part of voice ergonomic assessment in voice patients.