Semi-occluded Vocal Tract Exercises Research Articles

Using Semi-Occluded Vocal Tract Exercises as a Vocal Tract "Reset"

Abstract: For decades, the benefits of semi-occluded vocal tract exercises (SOVTEs) in voice training and rehabilitation have been extolled, most especially how SOVTEs impact phonation. However, a second important, yet neglected aspect of SOVTEs identified in numerous research studies is how they affect the shape of the vocal tract. This article highlights how SOVTEs can passively expand the airway, alleviating unintended constrictions, freeing singers from attempting to "open the throat" through direct muscular activation. This expansion can serve as a vocal tract "reset," allowing singers to selectively shape the vocal tract, facilitatating the wide-narrow contrasts needed for singing in a variety of musical genres.

Extrinsic Laryngeal Muscle Activity With Different Diameters and Water Depths in a Semi-Occluded Vocal Tract Exercise.

Surface electromyography (sEMG) has been used to evaluate extrinsic laryngeal muscle activity during swallowing and phonation. In the current study, sEMG amplitudes were measured from the infrahyoid and suprahyoid muscles during phonation through a tube submerged in water. The sEMG amplitude values measured from the extrinsic laryngeal muscles and the electroglottographic contact quotient (CQ) were obtained simultaneously from 62 healthy participants (31 men, 31 women) during phonation through a tube at six different depths (2, 4, 7, 10, 15, and 20 cm) while using two tubes with different diameters (1 and 0.5 cm). With increasing depth, the sEMG amplitude for the suprahyoid muscles increased in men and women. However, sEMG amplitudes for the infrahyoid muscles increased significantly only in men. Tube diameter had a significant effect on the suprahyoid sEMG amplitudes only for men, with higher sEMG amplitudes when phonating with a 1.0-cm tube. CQ values increased with submerged depth for both men and women. Tube diameter affected results such than CQ values were higher for men when using the wider tube and for women with the narrower tube. Vocal fold vibratory patterns changed with the depth of tube submersion in water for both men and women, but the patterns of muscle activation differed between the sexes. This suggests that men and women use different strategies when confronted with increased intraoral pressure during semi-occluded vocal tract exercises. In this study, sEMG provided insight into the mechanism for differences between vocally normal individuals and could help detect compensatory muscle activation during tube phonation in water for people with voice disorders.

A Study on Vocal Attack During Voice Therapy Exercises Using Photoglottography

ObjectiveThere are various exercises for voice therapy, but current evidence is insufficient to decide the most effective training technique for each type of dysphonia. This study focused on vocal attack as one of the causes of dysphonia. Hence, vocal attack during voice therapy exercises was investigated using photoglottogram (PGG). MethodsEighteen healthy adult subjects (10 males and 8 females) were included in this study. The first to fifth vocal waves during natural voice, hard and soft voice onset, and semi-occluded vocal tract exercises (SOVTE: humming, tubing, and lip trill) were assessed. We also calculated the 25% vocal fold open quotient (OQ) using a PGG and compared these parameters. ResultsThe 25% OQ did not show any sex-related differences. In the first wave, the 25% OQ for hard attack was significantly lower than that for soft attack, tongue out humming, and lip trill. In contrast, the 25% OQ value for soft attack was significantly higher than that for humming, 6 mm tube phonation, and lip trill. The 25% OQ values differed between SOVTE procedures; it was higher for the 13 mm tube phonation than for the 6 mm tube phonation. The 25% OQ at voice onset in the first to fifth waves differed depending on the SOVTE technique, indicating different voice onset patterns. ConclusionsThese results suggest that appropriate selection of SOVTE tailored for each patient may have benefit in further voice improvement. Future research should focus on conducting a similar study on patients with dysphonia.

Effects of Semi-occluded Vocal Tract Exercises with Different Vibration Sources and Duration on Healthy Adults’ Voice

Objectives: This study aimed to explore the impact of semi-occluded vocal tract exercises (SOVTE) with varied vibration sources and durations on the vocal performance of healthy adults. In addition, we sought to confirm the safety of voiced high-frequency oscillation (VHFO) intervention and provide basic data for performances in relation to straw phonation (SP).Methods: The study included 34 healthy adults with no vocal impairments, comprising 8 males and 26 females. The mean age of the participants was 23.00±2.06 years. To assess vocal characteristics during VHFO and SP, voice samples were recorded at three specific time points: prior to performing SOVTE (M0), after 1 minute of exercise (M1), and after 3 minutes of exercise (M3). Cepstral, perturbation, electroglottographic analyses were conducted on the recorded samples of vowel and sentences. Psychometric evaluation was conducted using questionnaires to gauge the self-reported severity of voice and vocal fatigue.Results: No statistically significant differences were observed in the average number of performances or duration per phonation between the two methods. When compared to baseline, CPPV significantly increased after 1 minute and 3 minutes of performance and Acoustic Psychometric Severity Index of Dysphonia decreased after 3 minutes of performance in VHFO. Both methods exhibited no significant differences in terms of psychometric and electroglottographic measurements.Conclusion: Results objectively confirmed the safety of VHFO intervention. This study is clinically significant as it lays the groundwork for future development of optimal treatment regimens and therapeutic programs for voice disorder patients, using foundational data on VHFO.

Therapeutic Singing and Semi-Occluded Vocal Tract Exercises for Individuals with Parkinson's Disease: A Randomized Controlled Trial of a Single Session Intervention.

Individuals with Parkinson's disease (PD) experience speech and voice-related symptoms that diminish communication and quality of life. Semi-occluded vocal tract (SOVT) exercises are targeted interventions that, when combined with the positive psychosocial benefits of therapeutic group singing (TGS), may affect outcomes. The purpose of this study was to explore the effectiveness of SOVT exercises, specifically straw phonation combined with TGS, to improve voice quality and mood for individuals with PD. We used a true experimental pretest-posttest between-subjects design (i.e., randomized controlled trial) facilitated by a board-certified music therapist. All participants (N = 27) were randomly assigned to one of three groups (a) straw phonation combined with TGS (SP + TGS, n = 10), (b) TGS (n = 10), and (c) speaking-only control group (n = 7). Participants completed voice recordings for acoustic measures and the Visual Analogue Mood Scale for mood analysis before and after a 30-min intervention. The results demonstrated significant improvement in voice quality evidenced by decreasing Acoustic Voice Quality Index scores following a single session for both SP + TGS and TGS intervention groups when compared to the control. Happiness scores improved in the experimental groups when compared to control. Although not statistically significant, participants in the experimental groups (SP + TGS, TGS) demonstrated better mean mood scores on happiness, anxiety, and angry when compared to control, indicating a positive psychological response to the singing interventions. Overall, this study indicated the effectiveness of SP + TGS and TGS as promising therapeutic interventions for voice quality and mood in individuals with PD.

Recent Research in Singing

Abstract: This Recent Research in Singing article chronicles three academic documents authored during 2023. Dissertations by Eun Chong Kang, “Femme Fatale in Lieder: Songs of Lorelei by Clara Schumann, Franz Liszt, and Alexander Zemlinsky”; Kristen Janell Sullivan, “Semi-Occluded Vocal Tract Exercises: Understanding the Prevalence and Purposes Within the Collegiate Voice Instructor Population”; and Melanie F Taylor, “The Songs of Pauline Viardot-García: Proposed Alternatives to Commonly Assigned Repertoire in the University Voice Studio.” Each includes a complete bibliographic citation and an Author/ProQuest abstract .

Presentation of the ATLETAS DA VOZ™ Conditioning Program

Objectives. To present a simple form of vocal and breathing conditioning for voice professionals based on concepts from vocal science. The vocal conditioning program called Voice Athletes Conditioning uses the principles of exercise physiology to gradually improve vocal and respiratory overload to achieve endurance, power, and flexibility. Methods. Due to our personal experience with high voice users, we synthesized a vocal conditioning program (AVCP) that combines voice science, exercise physiology, sports science and physical therapy principles. This is an 8-week program of daily vocal and breathing exercises with overload enhancement each week using different types of breathing devices and semi-occluded vocal tract exercises, designed and developed according to the specific requirements and performance of the voice professional. Reflections. Professional voice users often experience episodes of vocal fatigue that can directly affect their performance and vocal health. As with physical training for athletes, voice exercises can also contribute to improving vocal conditioning, preventing voice disorders, as well as helping to obtain better performance, greater tolerance to fatigue and shorter recovery time. Conclusions. AVCP is an approach that considers the principles of muscle training aimed objectively at the respiratory and vocal muscles, carried out with a variety of breathing devices and specific vocal exercises in search of greater performance time, less physiological stress, and shorter recovery time in the professional use of the voice.

Effectiveness of Semi-Occluded Vocal Tract Exercises (SOVTEs) in Patients with Dysphonia: A Systematic Review and Meta-Analysis.

Dysphonia is a disorder characterized by an alteration in the overall quality of the voice which reduces quality of life. Therefore, we assessed the effectiveness of SOVTEs in the management of dysfunctional and organic dysphonia for acoustic, perceptual-auditive, aerodynamic parameters and self-perception of the disease. a systematic review and meta-analysis were conducted. Findings were reported according to the PRISMA statement. Five databases were searched for RCTs and non- or quasi-RCTs. Studies were independently assessed using the Cochrane Risk of bias (RoB) and ROBINS-I tools. Effect sizes (ES) were calculated only at post-treatment. GRADE criteria were used to assess the quality of evidence. eight articles were included. Studies investigated several SOVTEs, alone or in combination. None of the study was completely judged at low RoB. The quality of evidence resulted very low for each analysis. SOVTEs revealed to be statistically more effective than control interventions in improving F0 (ES: -14.42; CI 95%: -27.16, -1.69); P=0.03), whereas shimmer did not change significantly (ES: -0.43; CI 95%:-02.02, 1.15; P=0.59). Not significant changes in favor of control groups were found for jitter (ES: 0.13; CI 95%: -0.14, 0.40; P=0.34) and overall gravity in the perceptual-auditory evaluation (ES: 0.13 CI 95%: -0.50, 0.77; P=0. 68). Among secondary outcomes, evidence suggested that SOVTEs are more effective than control interventions in Psub reduction (ES: -1.47; CI 95%: -2.84, -0.10; P=0.03); self-assessment resulted not significantly in favor of SOVTEs (VHI/VRQoL: ES -0.23; CI 95% -1.14, 0.69; P=0.63 and VTDS/VDSI: ES -4.85, CI 95% -25.13, 15.42; P=0.64). results obtained showed that voice therapy based on SOVTEs is not to consider significantly superior if compared to other treatments, even if a favorable trend was detected and should be taken into consideration. Further high-quality RCTs on specific SOVTEs are recommended to produce better-quality evidence.

Vocal Cool-Down In Voice Training: Method and Technical Considerations

Abstract In addition to the artistic aspect of professional voice performance, the sportive aspect is also important. The voices of professional voice actors, who are considered just like an athlete, should be strong, flexible and durable against long-term use. Also called vocal athletes, voice performers need processes such as muscle and skill development, voice warm up and cool down as in the applications expressed as periodization in sports medicine. Vocal training should aim to prepare the student for the stage not only with its artistic aspect but also with its sportive aspect. In the vocal training process, it is important to raise the awareness of the students from the very beginning of the education and to make the sportive discipline a behavior in the name of sustainable professional vocal use. It is unacceptable for a professional athlete to do some warm-up and cool-down movements with random movements or ignorance. The same is true for seeking vocal exercises for the singer.
 Exercise programs structured on a physiological basis both give predictable results, and the singer knows what to do and can ensure the performance. The most important components of the conscious training program that creates vocal periodization are vocal warming-up and cooling-down. Contrary to vocal warm-up exercises, studies on vocal cool-down are not sufficient both in the literature and in vocal training. It is an important necessity to apply vocal cool-down exercises in the same routine for the tissue recovery and to return to the speaking tone after the performance and to achieve tissue recovery under appropriate conditions. Vocal cool-down exercises are basically based on stretching and slowing down. In addition to metabolic effects such as blood flow changes, decreasing the muscle tonus, and removal of metabolites from the tissue; physiological effects such as providing a comfortable low larynx position and relaxation are targeted. Vocal cool-down techniques include semi-occluded vocal tract exercises, descending arpeggios, formant maneuvers, yawn&sigh, and chewing approach. In this study, the literature on vocal cool-down exercises has been reviewed, and ideal cool-down conditions and exercises have been presented in parallel with sports physiology.
 Keywords: Voice Training, Vocal Warm-up Exercises, Vocal Cool-down Exercises, Voice Health, Vocal Performance

Immediate Effects of Semi-Occluded Vocal Tract Exercises on Acoustic, Auditory-Perceptual, and Self-Perceptual Measures of Voice Production.

This study examined the immediate acoustic, auditory-perceptual, and self-perceptual effects of two semi-occluded vocal tract exercises (SOVTs): straw phonation and straw phonation into a cup of water, delivered in a remote setting. 36 participants (19 females and 17 males) completed a baseline battery of acoustic recordings, followed by one of two SOVTs, and an identical post-task battery. The procedure repeated itself to include the other SOVT. Participants were also asked to rate their self-perceived vocal effort and quality following each condition. Recordings were presented to three expert listeners for completion of auditory-perceptual analysis. Acoustically, a significant decrease in shimmer was noted following straw phonation. Auditory-perceptual analysis revealed a significant increase in the perception of strain following straw phonation into a cup of water. While no significant differences were found between SOVT tasks in self-perception of vocal effort, a significant increase in self-perception of vocal loudness was reported following straw phonation into a cup of water. SOVTs have a varied, yet significant short-term impact across acoustic, auditory-perceptual, and self-perceptual measures of voice production. Straw phonation provided consistently significant acoustic results, with nearly every variable improving to some degree. Results also support the notion that shimmer is an acoustic measure that is particularly susceptible to change following modest manipulation. These results, in addition to the auditory-perceptual and self-perceptual findings, have a direct impact on how SOVTs are being used clinically and may generalize to inform the way voice metrics are collected and analyzed.

Effects of a Straw Phonation on Acoustic and Self-Reported Measures of Adolescent Female Singers: A Pilot Study

ABSTRACT Characteristics of adolescent female voice change include breathiness, inconsistent pitch, “cracks,” abrupt register transitions, vocal range changes, and decreased stamina. Researchers have found that semi-occluded vocal tract exercises (e.g. straw phonation) can assist with such difficulties with other varied populations, facilitating glottal closure, decreasing breathiness, and encouraging easier voicing. Therefore, the purpose of this investigation was to measure the effects of straw phonation (experimental) compared to “ah” vowel (control) warm-ups on acoustic and self-reported measures of seventh-grade female-identifying singers. We calculated each participant’s Acoustic Voice Quality Index (AVQI) prior to and after a 4–5-minute straw phonation (n = 6) or unoccluded “ah” vowel (n = 6) warm-up. Results indicated robust improvement in AVQI scores after both warm-ups, with a trend toward more acoustic improvement after straw phonation (5 improved, M = 0.48, compared to 4, M = 0.35). All participants self-reported that their respective voicing helped them to be more warmed up, but the effect was statistically much larger in the straw group (7.23 to 5.00, 10-point scale). Some participants self-reported that straw phonation was more effective than their typical warm-up. These results may indicate more robust benefits from straw phonation, which could facilitate increased motivation during a difficult transition.

The effect of vocal tract semi-occlusion on the voice source and implications for voice therapy

Semi-occluded vocal tract exercises are often used in voice therapy to improve voice production. It is generally assumed that by enhancing source-filter interaction, such vocal exercises improve vocal efficiency while minimizing vocal fold collision. The goal of this computational study is to quantify such effects of source–filter interaction on the voice source. Voice simulations were performed with vocal tract constriction at various locations (false vocal folds, aryepiglottic folds, pharynx, oral cavity, and lips). The results showed that effects of vocal tract constriction on the voice source were generally small except for conditions of extreme constriction, at which constrictions at any location along the vocal tract decreased the mean and peak-to-peak amplitude of the glottal flow waveform. In general, source-filter interaction that reduced vocal fold contact pressure also decreased sound pressure level, thus making it impractical when targeting a desired output vocal intensity. While source–filter interaction is often assumed to improve vocal efficiency and economy, our results indicate that such improvements are mainly due to improvement in the filter rather than the voice source at the glottis. It is possible that speakers make additional laryngeal adjustments during vocal exercises, which may also contribute to the therapeutic benefits of such exercises.

Duration of vocal effects due to water resistance therapy

There are only few data about effects of semi-occluded vocal tract exercises on vocal fold oscillation patterns in vivo. Furthermore, it has not yet been clarified for how long these effects last. Material: 16 subjects (8 non-pathological and 8 with vocal fold mass lesion) were asked to sustain a phonation on the vowel /i/. During phonation, the subjects were simultaneously recorded with transnasal high speed videoendoscopy (HSV, 20.000 fps), electroglottography, and audio signals. After that, these subjects performed a Water Resistance Therapy (WRT) for 10 min (tube 30 cm, 9 mm diameter, 5 cm below surface). Repeated measurements of sustained phonation were performed 0, 10, and 30 min after exercising. The data showed strong inter-individual differences concerning the courses of the different measures after WRT. For non-pathological voices, directly after WRT there was a lowering of the Glottal-Area-Waveform derived Period-Perturbation -Quotient, a lowering of the closing quotient. For pathological voices, however, such a decrease was not observable. Five minutes after the exercise such effect was not observable any more. WRT showed strong inter-individual effects in the courses of the evaluated measures. General tendencies of some measures directly after the intervention showed a brief effect of only a few minutes.

Voicing for Life: A Study to Explore the Benefits of Linklater Voice in a Community Music Curriculum

ABSTRACT This study had two objectives. Within the training programs of community musicians, we sought to investigate the relationship between community music-makers and voice habilitation practices. We also sought to understand how community music-makers learn to adapt their personal vocal practices to an undergraduate curriculum. Ten community musicians participated in this study. They were drawn from a class that was following aspects of Kristin Linklater’s voice progression framework as laid out in her book Freeing the Natural Voice. Linklater’s material was supplemented with other interventions thought to promote voice habilitation, such as laryngeal massage (Mathieson 2011) and semi-occluded vocal tract exercises. Data was collected through class observations, interviews and surveys. While the body of participants was admittedly small, we did see evidence that the vocal habilitation practices advocated by the Linklater voice progression framework seemed to support the efforts of these community musicians to express themselves more effectively. A greater sample may add dimension to these preliminary findings. More study is needed.

Evaluation of Immediate Effects of Straw Phonation Exercise and Determination of the Ideal Performance Time in Healthy Adults

The ideal performance time of straw phonation exercise, one of the semi-occluded vocal tract exercise types, in which optimal effects are seen in healthy voices is still unknown. The aim of this study was to investigate the immediate effect of straw phonation exercise in healthy adults after 1, 3, 5, 7, and 10 minutes, considering: acoustic parameters, electroglottographic parameters, auditory-perceptual general voice quality, the participants' self-assessment regarding vocal effort, and laryngeal discomfort during exercise. This study included 69 participants (35 women, 34 men) with a healthy voice. Participants performed the exercise with straw for a total of 10 minutes. The data were collected before (m0) and immediately after exercises at the first (m1), third (m3), fifth (m5), seventh (m7), and tenth (m10) minutes of performance using sustained emission of vowel /a/ and a sentence. There was an increase in the fundamental frequency at m7 and a decrease in the shimmer from m5 in men. The sound pressure level increased at m5 and m10 in women and from m1 in men. The Acoustic Voice Quality Index score decreased at m5 in men. The mean average closed quotient decreased at m10 in women. Auditory-perceptual general voice quality was optimal at m3 in women and at m5 in men, it deteriorated at m7 in women and at m10 in men. The vocal effort during the exercise increased at m7 in women and at m10 in men. The laryngeal discomfort during the exercise increased for both sexes at m10. The straw phonation exercise in healthy individuals promoted optimal effects on voice quality after 5 and 7 minutes for men and 3 and 5 minutes for women. Prolongation of the exercise time causes negative effects on voice quality and an increase in vocal effort and laryngeal discomfort presented by the participants.

Clinical Experiences of Speech-Language Pathologists in the Rehabilitation of Unilateral Vocal Fold Paralysis

Unilateral vocal fold paralysis (UVFP) is a neurological voice disorder that is often first treated by a speech-language pathologist (SLP). In literature, little consensus is found regarding voice therapy onset, duration, frequency, and content. The aim of the current study is to investigate the clinical practice of SLPs for treatment of UVFP regarding diagnostics and treatment characteristics. Additionally, the study examined the personal experiences of SLPs regarding UVFP care. An online survey was completed by 37 respondents, all SLPs with experience in treating UVFP. Demographic characteristics, experiences with voice assessments and treatment modalities were examined. Lastly, experiences and opinions of SLPs on evidence-based practice and their own clinical practice were surveyed. Almost all respondents used a multidimensional voice assessment with findings from laryngovideostroboscopy to assess UVFP. Laryngeal electromyography is not yet integrated in regular clinical practices. The most commonly used vocal techniques were resonant voice exercises, laryngeal manipulation, semioccluded vocal tract exercises (SOVTEs), vocal hygiene, and Vocal Function Exercises, with SOVTEs most often considered effective. A total of 75% of the respondents feel confident treating UVFP, and 87.6% believe it is important to stay updated on evidence-based practice. Variation in therapy timing and dosage was observed, and 48.4% of SLPs usually started early voice therapy within 4 weeks after UVFP onset. Flemish SLPs generally feel confident treating UVFP patients and show interest in improving evidence-based practice. Initiatives to train clinicians further in UVFP care and encouraging SLPs to provide practice-based evidence will enhance the knowledge base for evidence-based practice in UFVP.

Optimizing Aerodynamic Vocal Parameters by Varying Supraglottic Pressure Using “Controlled Supraglottic Pressure Phonation” in Healthy Subjects

The objective of this study is to introduce a novel method for semi-occluded vocal tract (SOVT) therapy called "controlled supraglottic pressure phonation," determine the mechanism by which supraglottic pressure contributes to lowering impedance during SOVT therapy, and provide the optimal supraglottic pressure range for SOVT exercises. Twenty-five human subjects were assigned to one of five supraglottic pressure levels, 0, 2, 4, 6, and 8 cmH2O, which were controlled through a continuous positive airway pressure device. Subjects were asked to phonate during both a short- and long-duration task, in which vocal properties were measured before and after. At the end of each task, the subjects reported the levels of discomfort and phonation difficulty on a 0-10 scale to assess the subjective improvement of vocal economy. Significant differences were observed between pre- and post-task measurements for phonation threshold pressure for both the short-duration and long-duration tasks. Phonation threshold flow and frequency measurements were found to have no statistically significant differences. The subjective measures showed elevated discomfort in the higher pressure inputs for both tasks relative to no air. Higher supraglottic pressure levels will improve ease of phonation, but the treatment discomfort needs to be considered as well, yielding an optimal supraglottic pressure range of 4-6 cmH2O. "Controlled supraglottic pressure phonation" serves as an alternative to straw phonation that may produce additional benefits.

Immediate effects of straw phonation in air or water on the laryngeal function and configuration of female speech-language pathology students visualised with strobovideolaryngoscopy: A randomised controlled trial.

A promising way to obtain vocal economy and efficiency is by semi-occluding the vocal tract while phonating. Current knowledge about the immediate effects of semi-occluded vocal tract (SOVT) phonation on the laryngeal function and configuration is based mainly on computer modelling or excised larynges studies. In in vivo SOVT studies, electroglottography (EGG) has been the most commonly used laryngeal outcome, showing contradictory results between studies. Therefore, exploring these aspects by direct visualisation of the human larynx during SOVT phonation using strobovideolaryngoscopy (SVL) is needed. The aim of this study was to investigate and compare the immediate effects of straw phonation (SP) in air, SP in 2cm water, and SP in 5cm water (with stirring straws), on the laryngeal function and configuration of a homogeneous group of vocally healthy female speech-language pathology students, visualised with flexible SVL. A randomised controlled trial was used. Fifty-two female speech-language pathology students (mean age: 18.7 years, SD: 0.6) were assigned randomly to one of three experimental groups or a control group: (1) SP in air, (2) SP in 2cm water, (3) SP in 5cm water or (4) [u] phonation with similar soft onset and slightly pursed lips as in SP but without a straw (control group). The participants underwent flexible SVL during habitual [u] phonation, followed by the specific SOVT exercise of their group assignment. All video samples were evaluated randomly and blindly by two experienced investigators using the Voice-Vibratory Assessment with Laryngeal Imaging (VALI) rating form, first independently and then by consensus. Compared to habitual phonation, the vibrational amplitude decreased during SP in 5cm water and SP in 2cm water, being more prominent in the first, more flow-resistant exercise. The mucosal wave also decreased during SP in 5cm water. The anteroposterior (AP) supraglottic compression similarly increased during SP in air, SP in 2cm water, and SP in 5cm water. Further, a rise in mediolateral (ML) compression and a decrease in phase symmetry and regularity were found during SP in 2cm water. A similar decrease in regularity was observed during SP in 5cm water. Both SP in air and SP in water cause positive immediate laryngeal effects for voice training opportunities. More AP supraglottic activity found during each SP exercise might indicate epilarynx narrowing, an economic phenomenon associated with SOVT. Immersing the straw in water additionally diminished the vibrational amplitude, lowering vocal fold impact stress and risk for phonotrauma during the exercise. The decreased regularity of the vibrational cycles during SP in water might be due to the varying back pressure created by the water bubbling. The impact of SP in water on ML supraglottic compression needs further investigation. What is already known on the subject A promising way to obtain vocal economy and efficiency is by semi-occluding the vocal tract while phonating. Current knowledge about the immediate effects of semi-occluded vocal tract (SOVT) phonation on the laryngeal function and configuration is based mainly on computer modelling or excised larynges studies. In in vivo SOVT studies, electroglottography (EGG) has been the most commonly used laryngeal outcome, showing contradictory results between studies. Therefore, exploring these aspects by direct visualisation of the human larynx during SOVT phonation using strobovideolaryngoscopy (SVL) is needed. What this paper adds to existing knowledge Group results of the current study generally support earlier computer modelling and in vivo studies, strengthening the current SOVT knowledge. Both SP in air and SP in water cause positive immediate laryngeal effects for voice training opportunities. More anteroposterior (AP) supraglottic activity found during each SP exercise might indicate epilarynx narrowing, an economic phenomenon associated with SOVT. Immersing the straw in water additionally diminished the vibrational amplitude, lowering vocal fold impact stress and risk for phonotrauma during the exercise. The decreased regularity of the vibrational cycles during SP in water might be due to the varying back pressure created by the water bubbling. The impact of SP in water on ML supraglottic compression needs further investigation. What are the potential or actual clinical implications of this work? Current results support that both SP in air and SP in water can be useful exercises in voice training. SP in water has shown the additional gain of lowering the vibrational amplitude during the exercise, hence supporting its appropriateness for vocal warm-ups by minimising vocal fold impact stress and the risk of phonotrauma. In the future, large-scale randomised controlled trials in other subgroups of voice users, including dysphonic patients, are needed to support evidence-based practice. SVL can facilitate the search for individualised training and therapy approaches.

The Insertion of Semioccluded Vocal Tract Exercises in the Teaching and Practice of Vocal Technique - A systematic review and Case Study among Vocal Technique Teachers Residing in Brazil and Portugal

The literature related to the physiology of the singing voice has gained more and more space within the teaching and practice of singing both in relation to understanding of concepts related to this practice regarding the use of specific vocal exercises, among them, semioccluded vocal tract exercises (SOVTE).

The Insertion of Semioccluded Vocal Tract Exercises in the Teaching and Practice of Vocal Technique - A systematic review and Case Study among Vocal Technique Teachers Residing in Brazil and Portugal

The literature related to the physiology of the singing voice has gained more and more space within the teaching and practice of singing both in relation to understanding of concepts related to this practice regarding the use of specific vocal exercises, among them, semioccluded vocal tract exercises (SOVTE).