Immediate effects of semi-occluded vocal tract exercises in low and high voices: a self-perception study

To investigate the self-perception by individuals on the immediate effects of three semi-occluded vocal tract exercises (SOVTE), that is, phonation into a latex tube, finger kazoo and phonation into a high-resistance straw, and to compare the self-perception results between the high and low voice groups.

The study participants consisted of 26 choristers (seven sopranos, seven altos, six tenors, and six basses) subdivided into high and low voices with ages ranging from 18 to 58 years. Voice samples of each subject were recorded before and after performing the exercises randomly for three subsequent weeks. A self-assessment questionnaire was applied.

All exercises had a statistically significant improvement, according to the participants' self-perception. Latex tube phonation was the preferred technique for 11 (84.62%) participants in the low voice group; while the high-resistance straw was reported as the less beneficial exercise by 10 (79.92%) participants in the same group. On the other hand, the high-resistance straw (9; 69.2%) was the preferred exercise for the high voice group; while finger kazoo (6; 46.15%) and latex tube (5; 38.4%) were the least beneficial exercises.

The study showed that the effects of these exercises are different and should be suited for each type of voice, such as the latex tube, which was the most preferred by low voice participants and also rated as less beneficial by high voice participants, and the high-resistance straw, which was the most preferred by the high voice participants and also rated as less beneficial by low voice participants.