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Exercise Science Principles and the Vocal Warm-up: Implications for Singing Voice Pedagogy
ARTICLE IN PRESS Exercise Science Principles and the Vocal Warm-up: Implications for Singing Voice Pedagogy *Matthew Hoch and †Mary J. Sandage, *†Auburn, Alabama Summary: Objectives/Hypotheses. Principles from exercise science literature were applied to singing warmup pedagogy as a method for examining parallels between athletic and voice training. Analysis of the use of exercise principles in vocal warm-up should illuminate aspects of voice training that may be further developed in the future. Methods/Design. A selected canon of standard voice pedagogy texts and well-regarded warm-up methods were evaluated for use of exercise science principles for skill acquisition and fatigue resistance. Exercises were then categorized according to whether they were used for the purpose of skill acquisition (specificity), training up to tasks (overload), or detraining (reversibility). Results. A preliminary review of well-established voice pedagogy programs reveals a strong bias toward the skill acquisition aspects of vocal warm-up, with little commentary on the fatigue management aspects. Further, the small number of vocalises examined that are not skill-acquisition oriented fall into a third “habilitative” category that likewise does not relate to overload but may play a role in offsetting reversibility. Conclusions. Although a systematic pedagogy for skill acquisition has emerged in the literature and practice of voice pedagogy, a parallel pedagogy for fatigue management has yet to be established. Identification of a systematic pedagogy for training up to specific singing genres and development of a singing maintenance program to avoid detraining may help the singer avoid injury. Key Words: Pedagogy–Exercise–Warm-up–Skill acquisition–Fatigue resistance. INTRODUCTION Throughout most of its history, singing voice pedagogy has focused on the vocal warm-up as having essentially one purpose: acquisition of a specific set of skills necessary to sing a specific genre of classical repertoire. An examination of the classic methods of Vaccai,1 Concone,2 Panofka,3 and Marchesi,4 four of the most popular and still-used methodologies, reveals that these pedagogical staples are organized almost entirely by vocalises geared toward various facets of skill acquisition. Concepts such as breath management and resonance (vocal tract tuning)—quintessentially important to the classical singer— are largely ignored in these publications. Although it is safe to assume that these aspects of classical singing were highly valued and thus addressed by the singing teacher, there was not an extensive discourse about these topics in pedagogical works. In 1967, two seminal voice pedagogy works, William Vennard’s Singing: The Mechanism and the Technic 5 and D. Ralph Appelman’s The Science of Vocal Pedagogy: Theory and Application,6 paved the way for a new era of voice pedagogy that revolutionized undergraduate and graduate curricula throughout the United States. The master-apprentice method of teaching, although still alive and well, was now blended with one that was more scientific and fact-based in nature. Then, in 1986, Richard Miller published The Structure of Singing: System and Art in Vocal Technique.7 This book advocated for a systematic method for training singers, one that blended goal-oriented vocalises with explanations that were firmly grounded in practical voice science. Accepted for publication March 28, 2017. This work is novel and solely the responsibility of the authors. From the *Department of Music Auburn University Auburn, Alabama; and the †Department of Communication Disorders, Auburn University, Auburn, Alabama. Address correspondence and reprint requests to Matthew Hoch, Department of Music, Auburn University, Auburn, AL 36849. E-mail: [email protected] Journal of Voice, Vol. ■■, No. ■■, pp. ■■-■■ 0892-1997 © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jvoice.2017.03.018
Despite a long-held belief that vocal warm-up is essential for singers, the physiological mechanisms for its benefits are not well understood. Warm-up in athletics has been regarded as theoretically beneficial for physiological, psychological, and injuryprevention reasons. Physiological benefits of warm-up include, but are not limited to, faster enzyme catalysis at muscle temperature changes above 0.05°C and faster propagation of the neural impulse.8,9 Psychologically, pre-performance arousal and re-establishment of muscle activation patterns (a component of motor planning) are attributed to improved performance.10 Injury prevention is described as a combination of skill acquisition and the development of fatigue-resistance,11 the latter of which is a little-considered aspect of singing training. Given that the muscle engagement for warm-up before performance adds to the cumulative use of the target muscle group(s), warm-up activity may also be considered a component of fatigue-resistance training. Bioenergetically, muscle fibers that are being employed for physical activity are using up energy reserves and enzymes that are available for muscle metabolism, regardless of whether it is for warm-up or performance.8 From this perspective, warm-up should not be separated from performance as a distinct muscle endeavor.12 The evidence to support the performance advantages of warmup is controversial and requires a more nuanced evaluation of the level of training, the duration and intensity of the warmup, and the performance variables required for the target activity.13 Exercise training principles, such as specificity, overload, and reversibility, can be used to pursue this more nuanced assessment of well-regarded and published warm-up regimes. The specificity principle states that changes in muscle function are very specific to the type of exercise, even when the same muscle groups are used. This is because specific muscle groups are recruited for specific tasks. For example, if an athlete wants to improve his leg presses, he must practice leg presses. Practicing squats will not help to improve his leg presses, even though squats employ the same muscles as leg presses,1 hence the
ARTICLE IN PRESS 2 specificity principle. By extension of this principle, skill acquisition exercises must be thoroughly grounded in the specific repertoire that the singer is being trained to perform. For example, classical Italian fioratura vocalises will do little to help train the Broadway belter in her upper chest-mix. Rather, these exercises will only help the classical singer improve her flexibility in selected passages of Italian bel canto repertoire. For the Broadway belter to improve her upper chest-mix, she must be assigned an exercise that directly addresses the upper chest-mix. The overload principle describes the requirement to work muscle tissue at an intensity or frequency above which it is used to working to achieve morphologic, metabolic, and neurologic changes to the tissue.11 Muscles need to be worked beyond what they are used to for them to continue to develop. The principle of reversibility indicates that the level of exercise intensity and frequency needs to be sufficient enough to prevent loss of these mechanisms that were upregulated with training.14 Should the frequency and intensity of muscle function (and cardiorespiratory function for that matter) decline, then all of those mechanisms (morphologic, metabolic, and neurologic) that were upregulated during training will downregulate to a new level of homeostasis. As the old adage goes, it is easier to stay in shape than to get in shape. Questions remain about length and intensity of warm-up relative to the singing performance expectations. Research needs to be done to quantify the length and intensity of singing performance endeavors so that we can better understand how the warm-up process should be designed to enhance and not detract from optimal performance. Although there is a large body of literature that applies exercise principles to athletic goals (running marathons, training specific skill acquisitions, etc), there is little research currently being done that applies these same principles to singing endeavors. Therefore, the goals of this research were to examine a standard body of writings and methods relating to vocal technique and warm-up—both historical and modern—and examine them through the lens of well-established exercise science principles: skill acquisition and fatigue resistance in particular.
METHODS/DESIGN In this study, the authors examined a selection of standard voice pedagogy method books from the 19th century bel canto era to the present day for evidence of use of the exercise training principles of specificity, overload, reversibility, and fatigue management. Operational definitions for these concepts are described in the Introduction section. A preliminary review of the large body of singing pedagogy literature was chosen for this investigation in lieu of a systematic review for the purpose of identifying a need for a more thorough systematic review. For example, although there are dozens (if not hundreds) of early Italian methodologies, many of their structures and goals are quite similar in nature, and Vaccai, Concone, Panofka, and Marchesi are four of the methods that are most widely used in contemporary practice. Likewise, standard pedagogy textbooks before Miller’s The Structure of Singing—such as those by Vennard and Appelman—clearly have historical importance, but these
Journal of Voice, Vol. ■■, No. ■■, 2017
pre-Miller resources were avoided in an effort to make sure that scientific data were more current. The works of three “generations” of methodologists were studied, all of which are still used regularly in the 21st century voice studio: selected early Italian methodologists (Vaccai, Concone, Panofka, and Marchesi), Richard Miller’s The Structure of Singing (1986), and Ingo Titze’s “Vocal Warm-ups: What Do They Accomplish?” (2000).15 The exercise regimens presented in these standard treatises were examined according to organization (content and sequence) and categorization of specific technical skill addressed in each exercise. In addition, a core list of standard voice pedagogy textbooks was consulted and examined for content relating to singing voice warm-up. Using search engines available in Google Scholar, Academic Search Premier, and EBSCO, a search of literature published after Titze’s seminal 2000 article was conducted. The following search terms were used: singing, solo singing warm-up, singing warm-up length, and routine singing warm-up. The review targeted individual singing warm-up publications that included information regarding length of warm-up, specific vocalises, and physiological goals of warm-up. Studies that addressed choral warm-up were not included. These data were then examined for evidence of the exercise warm-up and training principles of reversibility and fatigue resistance as operationally defined above. Reversibility was coded if the resource being evaluated described any pedagogical considerations for loss of trained skill secondary to extended vocal rest or hiatus from singing exercise. Fatigue resistance was coded if the resource being evaluated addressed pedagogical aspects of systematically training the voice to be able to perform longer or recover faster. Absence of these physiological aspects of fatigue resistance training, which are commonly accounted for in exercise science, served as indicator that fatigue resistance training was not considered. RESULTS A review of these resources suggests that historical singing pedagogy resources do not address singing warm-up specifically, at least in the modern muscle physiological sense. An examination of these resources indicated that voice pedagogy has historically been oriented toward skill acquisition while ignoring other aspects of muscle training and tissue upregulation, on which current paradigms for performance warm-up are based. Table 1 summarizes the analyses of historical singing voice pedagogy according to skill acquisition parameters that were well-recognized for singing voice training before the modern evidence-based era. Table 2 summarizes the findings from the more contemporary body of literature. DISCUSSION The goal of this preliminary pedagogical analysis was to identify inclusion of exercise training principles in singing warm-up regimes. The findings indicate that skill acquisition has been a focus of singing warm-up approaches for some time, with attention toward other principles of muscle training (specificity, overload, reversibility, and fatigue management) as a more recent development. Principles of reversibility and fatigue resistance were not present in any of the singing warm-up programs reviewed.
ARTICLE IN PRESS Matthew Hoch and Mary J. Sandage
TABLE 1. Vocalises From the Historical International Italian School Vaccai Panofka Marchesi Concone Legato Flexibility Style Musicianship Vowels only Text/poetry Messa di voce (register blending) No categorization*
X X X X
X X X X X
3
Implications for Singing Voice Pedagogy
X X X X X
X
X X
X
Metoda pratico de canto (1832): Nicola Vaccai (1790–1848); 50 Lezioni, Op. 9: Giuseppe Concone (1801–1861); 24 Vocalizzi, Op. 81 and 24 Vocalizzi progressivi, Op. 85: Heinrich Panofka (1807–1887); and Method de chant théorique et pratique, Op. 31 (1886): Mathilde Marchesi (1821–1913). * Specific skills addressed, but author declines to categorize or organize material for the singer.
The author most often given credit for establishing a widely used systematic pedagogy is Richard Miller (1926–2009). His seminal book, The Structure of Singing,7 was influential on the voice teaching profession. Miller’s taxonomy approached skill acquisition by categorizing specific vocal tasks into a variety of specific
categories, including onset and release, breath management, agility or flexibility, resonance, registration, and dynamic control. He also provided progressive exercises for each category, and— perhaps most important of all—he offered extensive commentary on the physiological backdrop for each skill. This approach represented a major leap forward for teachers of singing. Although Vaccai and Concone addressed many of the skills expounded on by Miller, no explanations accompanied their exercises, and they also did not benefit from the scientific knowledge accessible to today’s evidence-based singing pedagogues. Throughout the history of singing pedagogy, voice training has focused overwhelmingly on the acquisition of specific skills as opposed to aspects of fatigue resistance. Fatigue resistance is operationally defined as warm-up or singing activity that was specifically designed to build the voice to be increasingly resistant to fatigue mechanisms. This is true whether one examines the early Italian methodologists—Vaccai, Concone, Panofka, and Marchesi, for example—or the evidence-based pedagogues of the late 20th century, such as Coffin et al,32,33 Miller,7,21,34 Doscher,23 and Smith and Chipman.29 To illustrate this historical bias toward skill acquisition, it is helpful to examine some of the most frequently used vocalises from the historical International Italian School as outlined in Table 1. Each of these volumes lays out a systematic approach toward skill acquisition in singers. With the exception of Concone, the
TABLE 2. Pedagogical Resources Reviewed for Warm-up, Skill Acquisition, and Fatigue Resistance Citation Lamperti (1931)16 Kagen (1950)17 Bunch (1982)18 Reid (1983)19
Miller (1986)7 Miller (1990)20 Miller (1996)21 Sundberg (1987)22 Doscher (1993)23 Elliot et al (1995)24 David (2008)36 Ware (1998)25 Titze (2000)15 Blades-Zeller (2002)26 Milbrath and Solomon (2003)37 Sell (2005)27 Amir et al (2005)28 Smith and Chipman (2007)29 Wicklund (2009)38 Gish et al, (2012)30 McCoy (2012)31
Length of Warm-up Not specified Not specified Not specified Varies according to technical skill of singer: more experienced = less time Less than 20–30 minutes (excess could result in fatigue) Not specified Not specified 30 minutes Not specified Not specified Not specified (NS) Not specified 15–20 minutes
Warm-up Type
Participant Type
Skill Acquisition
Fatigue Resistance
Injury Prevention
NS NS NS Coached
NS NS NS All levels
NS NS NS Yes
NS NS NS Yes
NS NS NS NS
Coached
All levels
Yes
Yes
NS
NS NS Coached Coached NS Self NS Recorded
NS NS Amateurs All levels NS All levels NS Amateurs
NS NS Yes Yes NS NS NS Yes
NS NS NS Yes NS Yes NS Yes
NS NS NS NS NS Yes NS Yes
All levels
Yes
Yes
NS
11 minutes (mean duration) Not specified
Coached Self Recorded NS
Advanced NS
Yes NS
NS NS
NS NS
Customized to singer’s needs 5–10 minutes Not specified
Coached Self Self NS
All levels
Yes
Yes
Yes
Professionals NS
Yes NS
NS NS
NS NS
20–30 minutes
ARTICLE IN PRESS 4
Journal of Voice, Vol. ■■, No. ■■, 2017 VACCAI Metoda pratica de canto
PANOFKA 24 Vocalizzi, Op. 81
1.
The Scale
1.
Diatonic Scale
2.
Intervals of Fourths Intervals of Fifths
2.
Minor Scale
3.
Intervals of Sixths
3 4.
Agility
4.
Intervals of Sevenths Intervals of Octaves
5 6.
Thirds
5.
Semitones
7.
Legato (groups of two)
6.
Syncopation
8 12. Portamento
7.
Intervals of Octaves
13.
Dotted Notes (delle note puntate)
8.
Appoggiaturas (above and below) The Acciaccatura
14.
Syncopation
9.
Mordents (graduated exercises)
15.
Legato
10.
Turns (graduated exercises)
16.
Appoggiaturas, Turns, and Mordents
11.
Trill (introduction)
17.
Trills (introduction)
12.
Roulades
18.
Agility
13.
Glides (two methods)
19.
Trills
14.
On Recitative
20 21. Arpeggios
15.
Recapitulation (cumulative summary of techniques)
22 23. Chromatics
Intervals of Thirds
24.
Intervals
SKILLS ADDRESSED: Legato, Flexibility, Style, Musicianship INTERESTING FEATURE: the singer sings actual texts throughout method
SKILLS ADDRESSED: Legato, Flexibility, Style, Musicianship
FIGURE 2. Panofka—24 Vocalizzi, Op. 81.
FIGURE 1. Vaccai—Metoda pratica de canto. table of contents of each volume also are descriptive of the vocal skills addressed by each exercise. Figures 1–3 describe the table of contents for the volumes by Vaccai, Panofka, and Marchesi. Concone’s 50 vocalises cover largely the same set of skills as those of Vaccai, Panofka, and Marchesi, but Concone does not specifically categorize his exercises or label the specific purpose of each. It is also obvious, upon examination of these vocalizes, that the skills addressed are designed to prepare the singer for a specific genre: specifically, 19th century bel canto Italian opera, exemplified in the works of Gioacchino Rossini (1792–1868), Gaetano Donizetti (1797–1848), and Vincenzo Bellini (1801–1835). Interestingly, these three pillars of the bel canto repertory spent so much time composing that they wrote very little about singing or singing technique. It was up to methodologists like Concone, Vaccai, Marchesi, and Panofka to lay a pedagogical foundation. Geared almost entirely toward skill acquisition, these historical vocalises were designed to give singers the tools they need to perform this very specific repertoire, thus recognizing the need for specificity before that principle was ever formally described. In these historical vocalises, extra-technical considerations, such as musicianship and style, were also addressed, albeit peripherally. Although flexibility and evenness of the voice
throughout the range were routinely addressed, specific strategies for resonance and breath management were not explicitly discussed. This historic “international Italian” approach, which has been synonymous with voice pedagogy for two centuries, reached its zenith within the American school of voice pedagogy through two works by Richard Miller, arguably the most influential voice pedagogue of the second half of the 20th century. Miller’s first book, English, French, German, and Italian Techniques of Singing: A Study in National Tonal Preferences and How They Relate to Functional Efficiency (1977),35 was profoundly influential in convincing American pedagogues that Italian methodology was technically superior to alternative approaches, particularly in the area of breath management, advocated by Miller through the appoggio technique. His follow-up effort was The Structure of Singing (1986),7 a comprehensive and systematic approach to skill acquisition rooted in the Italian school. An examination of its table of contents (see Figure 4) demonstrates this work’s firm lineage and relationship to the 19th century methodologies listed above. Unlike the historical works, however, Miller also included commentary: he explains the purpose of each vocalise presented, and more importantly, described the basic physiology and rationale beyond the exercise and its place within the sequence. The
ARTICLE IN PRESS Matthew Hoch and Mary J. Sandage MARCHESI PART I
5
Implications for Singing Voice Pedagogy Op. 31
Elementary and Progressive Exercises
pratique, Op. 31
MARCHESI PART II
Development of the Exercises
1.
Emission of the Voice (attack)
1.
Attack
2.
Chromatic Slur
2 7.
Portamento
3.
Diatonic Slur
8 9.
Sostenuto
4 8.
Portamento
10 19.
Diatonic Scales
9 36.
Scales
20 21.
Dotted Diatonic Scales
37 73.
Exercises for Blending the Registers
22.
Minor Scale
74 125.
Exercises on Two, Three, Four, Six, and Eight Notes
23 25.
Major and Minor Scales (alternating)
126 135.
Chromatic Scales
26 27.
Chromatic Scales
136 137.
Minor Scales
28.
Repeated Notes
149 151.
Varied Scales
29.
Triplets
152 153.
Repeated Notes
30.
Arpeggios
154 162.
Triplets
31.
Appoggiatura and Acciaccatura
163 173.
Arpeggios
32.
Mordent and Turns
174.
Messa di Voce
33.
Syncopation
175 192.
Appoggiaturas, Acciaccaturas, Mordents, Turns
34.
Long Intervals
185 192.
Trills.
35.
Staccato, Mezzo-Staccato, and Accented Notes
36.
Trills
SKILLS ADDRESSED: Legato, Flexibility, Style, Musicianship INTERESTING FEATURES: Register blending, messa di voce mentioned
FIGURE 3. Marchesi—Method de chant théorique et pratique, Op. 31. influence of The Structure of Singing on modern voice pedagogy cannot be understated: more classical teachers teach like Miller than anyone else, and Miller’s concepts permeate modern voice pedagogy curricula. In his proposal of specific vocal warm-ups,15 Titze not only promotes a new generation of skill acquisition exercises, but also explains the scientific rationale behind each—they are designed to promote vocal efficiency as opposed to only being geared toward singing a specific kind of literature. Figure 5 outlines Titze’s warm-ups. Titze’s interest in muscle physiology suggests a “next step” for voice teachers interested in going beyond skill acquisition for skill acquisition’s sake. For singing teachers to better understand basic muscle physiology and training up their singers for specific tasks, exploring exercise science principles can be a fruitful avenue. There is a long and widely held belief that vocal warm-up is important for singers for both performance quality and vocal health. However, the physiological mechanisms for these benefits are not well understood. Within the exercise science literature, warm-up exercise that targets skill acquisition and trains fatigue
resistance is attributed to injury prevention.2 A few recently published pedagogical resources addressed skill acquisition and fatigue resistance specifically, but with little discussion devoted to the topic of injury prevention. More current resources that include the concepts of skill acquisition and fatigue resistance include Reid,19 Miller,7,20,21 Elliot et al,24 David,36 Sell,27 Amir et al,28 and Gish et al.30 Although fatigue resistance was not an explicit goal of these warm-up approaches, the longer warmup times recommended may result in upregulation of those physiological mechanisms that promote fatigue resistance. It is apparent from this review that attention to the specific benefits of vocal warm-up is a more recent consideration in the planning and execution of vocal warm-up. A little-discussed aspect in the traditional classical pedagogy texts and the published literature to date are the muscle physiology implications of muscle bioenergetics with regard to type and duration of singing warmup. Consideration of exercise science principles, particularly in the area of muscle training and skill acquisition, can be invaluable when assigning vocal warm-ups, and these vocalises should be thoroughly grounded in the specific repertoire that the singer will perform. Integrating these principles into one’s teaching
ARTICLE IN PRESS 6
Journal of Voice, Vol. ■■, No. ■■, 2017 MILLER
The Structure of Singing (1986)
TITZ
1.
-UPS (2000)
Lip trill, tongue trill, humming, or phonation into narrow
1.
Onset and Release
2.
Breath Management
tubes (all partial occlusions of vocal tract) on glides, scales,
3.
Agility/Flexibility
or arpeggios.
4.
Resonance
2.
Two-octave pitch glides, up and down, high vowels /i/ or /u/.
5.
Vowel Balancing
3.
Forward tongue roll and extension, vowel sequence /a/ /i/,
6 7.
Resonance (nasal and non-nasal consonants)
8.
Sostenuto
scales. 4.
high vowels, to low vowels.
9 10. Registration (male and female) 11.
Vowel Modification
12.
Range Extension
13.
Messa di voce and Dynamic Control
14.
Vibrato and Vocal Timbre
15 17. Extra-Technical Concerns
PRINCIPAL FEATURE: Detailed prose accompanies specific exercises.
FIGURE 4. Miller—The Structure of Singing (1986). routine encourages successful outcomes when honing specific aspects of singing technique. Untangling these various aspects of vocal technique through assessment rubrics can also prove to be invaluable. REFERENCES 1. Vaccai N. Practical Method of Italian Singing: For Soprano or Tenor. G. Schirmer; 2000. 2. Concone G. 50 Lezioni op. 9. Milan: Bertelsmann Music Group; 2005. 3. Panofka H. Vocalizzi. Milan: Bertelsmann Music Group; 2006. 4. Marchesi M. Marchesi Vocal Method, Op. 31. New York: Schirmer; 1986. 5. Vennard W. Singing: The Mechanism and the Technic. Carl Fischer, LLC; 1967. 6. Appelman DR. The Science of Vocal Pedagogy: Theory and Application, Vol. 378. Indiana University Press; 1967. 7. Miller R. The Structure of Singing: System and Art in Vocal Technique. Wadsworth Pub Co; 1986. 8. Brooks GA, Fahey TD, Baldwin KM. Exercise Physiology: Human Bioenergetics and Its Applications. 4th ed. Boston: McGraw-Hill; 2005. 9. Pearce AJ, Rowe GS, Whyte DG. Neural conduction and excitability following a simple warm up. J Sci Med Sport. 2012;15:164–168. 10. McArdle WD, Katch FI, Katch VL. Exercise Physiology: Nutrition, Energy, and Human Performance. Lippincott Williams & Wilkins; 2010. 11. Powers S, Howley E. Exercise Physiology: Theory and Application to Fitness and Performance. 9th ed. Boston: McGraw-Hill; 2014. 12. Sandage M, Smith A. Muscle bioenergetic considerations for intrinsic laryngeal skeletal muscle physiology. J Speech Lang Hear Res. 2016. 13. Witvrouw E, Mahieu N, Danneels L, et al. Stretching and injury prevention: an obscure relationship. Sports Med. 2004;34:443–449. 14. Sale DG. Influence of exercise and training on motor unit activation. Exerc Sport Sci Rev. 1986;15:95–151. 15. Titze IR. Vocal warm-ups: what do they accomplish? J Acoust Soc Am. 2000;107:2864.
Messa di voce, proceeding from a partially occluded tract to
5.
Staccato on arpeggios.
NOTE: Specifically geared toward muscle training and coordination.
FIGURE 5. Titze’s five favorite warm-ups (2000). 16. Lamperti GB. Vocal Wisdom: Maxims Transcribed and Edited by William Earl Brown. New York: Taplinger; 1931. 17. Kagen S. On Study Singing. New York, NY: Dover Publications; 1950. 18. Bunch M. Dynamics of the Singing Voice. Springer; 1982. 19. Reid CL. A Dictionary of Vocal Terminology: An Analysis. Joseph Patelson Music House; 1983. 20. Miller R. Warming up the voice. NATS J. 1990;46:22–23. 21. Miller R. On the Art of Singing. USA: Oxford University Press; 1996. 22. Sundberg J. The Science of the Singing Voice. DeKalb, IL: Northern Illinois UP; 1987. 23. Doscher B. The Functional Unity of the Singing Voice. Scarecrow Press; 1993. 24. Elliot N, Sundberg J, Gramming P. What happens during vocal warm-up? J Voice. 1995;9:37–44. 25. Ware C. Basics of Vocal Pedagogy: The Foundations and Process of Singing. McGraw-Hill; 1998. 26. Blades-Zeller E. A Spectrum of Voices: Prominent American Voice Teachers Discuss the Teaching of Singing. Scarecrow Press; 2002. 27. Sell K. The Disciplines of Vocal Pedagogy: Towards an Holistic Approach. Farnham, Surrey: Ashgate Publishing; 2005. 28. Amir O, Amir N, Michaeli O. Evaluating the influence of warmup on singing voice quality using acoustic measures. J Voice. 2005;19:252–260. 29. Smith WS, Chipman M. The Naked Voice: A Wholistic Approach to Singing, Vol. 1. Oxford University Press; 2007. 30. Gish A, Kunduk M, Sims L, et al. Vocal warm-up practices and perceptions in vocalists: a pilot survey. J Voice. 2012;26:e1–e10. 31. McCoy SJ. Your Voice, an Inside View: Multimedia Voice Science and Pedagogy. 2nd ed. Inside View Press; 2012. 32. Coffin B. Overtones of Bel Canto: Phonetic Basis of Artistic Singing: With 100 Chromatic Vowel-chart Exercises. Scarecrow; 1980. 33. Coffin B, Delattre P. Sounds of Singing, Metuchen. NJ: Scarecrow; 1987. 34. Miller R. Solutions for Singers: Tools for Performers and Teachers. Oxford University Press; 2004. 35. Miller R. English, French, German and Italian Techniques of Singing: A Study in National Tonal Preferences and How They Relate to Functional Efficiency. Scarecrow Press; 1977. 36. David M. The New Voice Pedagogy. 2nd ed. Lanham, MD: Scarecrow Press; 2008. 37. Milbrath RL, Solomon NP. Do warm-up exercises alleviate vocal fatigue?. J Speech Lang Hear Res. 2003;46:422–436. 38. Wicklund K. Singing Voice Rehabilitation: A Guide for the Voice Teacher and Speech-Language Pathologist. Boston: Cengage; 2009.
Despite a long-held belief that vocal warm-up is essential for singers, the physiological mechanisms for its benefits are not well understood. Warm-up in athletics has been regarded as theoretically beneficial for physiological, psychological, and injuryprevention reasons. Physiological benefits of warm-up include, but are not limited to, faster enzyme catalysis at muscle temperature changes above 0.05°C and faster propagation of the neural impulse.8,9 Psychologically, pre-performance arousal and re-establishment of muscle activation patterns (a component of motor planning) are attributed to improved performance.10 Injury prevention is described as a combination of skill acquisition and the development of fatigue-resistance,11 the latter of which is a little-considered aspect of singing training. Given that the muscle engagement for warm-up before performance adds to the cumulative use of the target muscle group(s), warm-up activity may also be considered a component of fatigue-resistance training. Bioenergetically, muscle fibers that are being employed for physical activity are using up energy reserves and enzymes that are available for muscle metabolism, regardless of whether it is for warm-up or performance.8 From this perspective, warm-up should not be separated from performance as a distinct muscle endeavor.12 The evidence to support the performance advantages of warmup is controversial and requires a more nuanced evaluation of the level of training, the duration and intensity of the warmup, and the performance variables required for the target activity.13 Exercise training principles, such as specificity, overload, and reversibility, can be used to pursue this more nuanced assessment of well-regarded and published warm-up regimes. The specificity principle states that changes in muscle function are very specific to the type of exercise, even when the same muscle groups are used. This is because specific muscle groups are recruited for specific tasks. For example, if an athlete wants to improve his leg presses, he must practice leg presses. Practicing squats will not help to improve his leg presses, even though squats employ the same muscles as leg presses,1 hence the
ARTICLE IN PRESS 2 specificity principle. By extension of this principle, skill acquisition exercises must be thoroughly grounded in the specific repertoire that the singer is being trained to perform. For example, classical Italian fioratura vocalises will do little to help train the Broadway belter in her upper chest-mix. Rather, these exercises will only help the classical singer improve her flexibility in selected passages of Italian bel canto repertoire. For the Broadway belter to improve her upper chest-mix, she must be assigned an exercise that directly addresses the upper chest-mix. The overload principle describes the requirement to work muscle tissue at an intensity or frequency above which it is used to working to achieve morphologic, metabolic, and neurologic changes to the tissue.11 Muscles need to be worked beyond what they are used to for them to continue to develop. The principle of reversibility indicates that the level of exercise intensity and frequency needs to be sufficient enough to prevent loss of these mechanisms that were upregulated with training.14 Should the frequency and intensity of muscle function (and cardiorespiratory function for that matter) decline, then all of those mechanisms (morphologic, metabolic, and neurologic) that were upregulated during training will downregulate to a new level of homeostasis. As the old adage goes, it is easier to stay in shape than to get in shape. Questions remain about length and intensity of warm-up relative to the singing performance expectations. Research needs to be done to quantify the length and intensity of singing performance endeavors so that we can better understand how the warm-up process should be designed to enhance and not detract from optimal performance. Although there is a large body of literature that applies exercise principles to athletic goals (running marathons, training specific skill acquisitions, etc), there is little research currently being done that applies these same principles to singing endeavors. Therefore, the goals of this research were to examine a standard body of writings and methods relating to vocal technique and warm-up—both historical and modern—and examine them through the lens of well-established exercise science principles: skill acquisition and fatigue resistance in particular.
METHODS/DESIGN In this study, the authors examined a selection of standard voice pedagogy method books from the 19th century bel canto era to the present day for evidence of use of the exercise training principles of specificity, overload, reversibility, and fatigue management. Operational definitions for these concepts are described in the Introduction section. A preliminary review of the large body of singing pedagogy literature was chosen for this investigation in lieu of a systematic review for the purpose of identifying a need for a more thorough systematic review. For example, although there are dozens (if not hundreds) of early Italian methodologies, many of their structures and goals are quite similar in nature, and Vaccai, Concone, Panofka, and Marchesi are four of the methods that are most widely used in contemporary practice. Likewise, standard pedagogy textbooks before Miller’s The Structure of Singing—such as those by Vennard and Appelman—clearly have historical importance, but these
Journal of Voice, Vol. ■■, No. ■■, 2017
pre-Miller resources were avoided in an effort to make sure that scientific data were more current. The works of three “generations” of methodologists were studied, all of which are still used regularly in the 21st century voice studio: selected early Italian methodologists (Vaccai, Concone, Panofka, and Marchesi), Richard Miller’s The Structure of Singing (1986), and Ingo Titze’s “Vocal Warm-ups: What Do They Accomplish?” (2000).15 The exercise regimens presented in these standard treatises were examined according to organization (content and sequence) and categorization of specific technical skill addressed in each exercise. In addition, a core list of standard voice pedagogy textbooks was consulted and examined for content relating to singing voice warm-up. Using search engines available in Google Scholar, Academic Search Premier, and EBSCO, a search of literature published after Titze’s seminal 2000 article was conducted. The following search terms were used: singing, solo singing warm-up, singing warm-up length, and routine singing warm-up. The review targeted individual singing warm-up publications that included information regarding length of warm-up, specific vocalises, and physiological goals of warm-up. Studies that addressed choral warm-up were not included. These data were then examined for evidence of the exercise warm-up and training principles of reversibility and fatigue resistance as operationally defined above. Reversibility was coded if the resource being evaluated described any pedagogical considerations for loss of trained skill secondary to extended vocal rest or hiatus from singing exercise. Fatigue resistance was coded if the resource being evaluated addressed pedagogical aspects of systematically training the voice to be able to perform longer or recover faster. Absence of these physiological aspects of fatigue resistance training, which are commonly accounted for in exercise science, served as indicator that fatigue resistance training was not considered. RESULTS A review of these resources suggests that historical singing pedagogy resources do not address singing warm-up specifically, at least in the modern muscle physiological sense. An examination of these resources indicated that voice pedagogy has historically been oriented toward skill acquisition while ignoring other aspects of muscle training and tissue upregulation, on which current paradigms for performance warm-up are based. Table 1 summarizes the analyses of historical singing voice pedagogy according to skill acquisition parameters that were well-recognized for singing voice training before the modern evidence-based era. Table 2 summarizes the findings from the more contemporary body of literature. DISCUSSION The goal of this preliminary pedagogical analysis was to identify inclusion of exercise training principles in singing warm-up regimes. The findings indicate that skill acquisition has been a focus of singing warm-up approaches for some time, with attention toward other principles of muscle training (specificity, overload, reversibility, and fatigue management) as a more recent development. Principles of reversibility and fatigue resistance were not present in any of the singing warm-up programs reviewed.
ARTICLE IN PRESS Matthew Hoch and Mary J. Sandage
TABLE 1. Vocalises From the Historical International Italian School Vaccai Panofka Marchesi Concone Legato Flexibility Style Musicianship Vowels only Text/poetry Messa di voce (register blending) No categorization*
X X X X
X X X X X
3
Implications for Singing Voice Pedagogy
X X X X X
X
X X
X
Metoda pratico de canto (1832): Nicola Vaccai (1790–1848); 50 Lezioni, Op. 9: Giuseppe Concone (1801–1861); 24 Vocalizzi, Op. 81 and 24 Vocalizzi progressivi, Op. 85: Heinrich Panofka (1807–1887); and Method de chant théorique et pratique, Op. 31 (1886): Mathilde Marchesi (1821–1913). * Specific skills addressed, but author declines to categorize or organize material for the singer.
The author most often given credit for establishing a widely used systematic pedagogy is Richard Miller (1926–2009). His seminal book, The Structure of Singing,7 was influential on the voice teaching profession. Miller’s taxonomy approached skill acquisition by categorizing specific vocal tasks into a variety of specific
categories, including onset and release, breath management, agility or flexibility, resonance, registration, and dynamic control. He also provided progressive exercises for each category, and— perhaps most important of all—he offered extensive commentary on the physiological backdrop for each skill. This approach represented a major leap forward for teachers of singing. Although Vaccai and Concone addressed many of the skills expounded on by Miller, no explanations accompanied their exercises, and they also did not benefit from the scientific knowledge accessible to today’s evidence-based singing pedagogues. Throughout the history of singing pedagogy, voice training has focused overwhelmingly on the acquisition of specific skills as opposed to aspects of fatigue resistance. Fatigue resistance is operationally defined as warm-up or singing activity that was specifically designed to build the voice to be increasingly resistant to fatigue mechanisms. This is true whether one examines the early Italian methodologists—Vaccai, Concone, Panofka, and Marchesi, for example—or the evidence-based pedagogues of the late 20th century, such as Coffin et al,32,33 Miller,7,21,34 Doscher,23 and Smith and Chipman.29 To illustrate this historical bias toward skill acquisition, it is helpful to examine some of the most frequently used vocalises from the historical International Italian School as outlined in Table 1. Each of these volumes lays out a systematic approach toward skill acquisition in singers. With the exception of Concone, the
TABLE 2. Pedagogical Resources Reviewed for Warm-up, Skill Acquisition, and Fatigue Resistance Citation Lamperti (1931)16 Kagen (1950)17 Bunch (1982)18 Reid (1983)19
Miller (1986)7 Miller (1990)20 Miller (1996)21 Sundberg (1987)22 Doscher (1993)23 Elliot et al (1995)24 David (2008)36 Ware (1998)25 Titze (2000)15 Blades-Zeller (2002)26 Milbrath and Solomon (2003)37 Sell (2005)27 Amir et al (2005)28 Smith and Chipman (2007)29 Wicklund (2009)38 Gish et al, (2012)30 McCoy (2012)31
Length of Warm-up Not specified Not specified Not specified Varies according to technical skill of singer: more experienced = less time Less than 20–30 minutes (excess could result in fatigue) Not specified Not specified 30 minutes Not specified Not specified Not specified (NS) Not specified 15–20 minutes
Warm-up Type
Participant Type
Skill Acquisition
Fatigue Resistance
Injury Prevention
NS NS NS Coached
NS NS NS All levels
NS NS NS Yes
NS NS NS Yes
NS NS NS NS
Coached
All levels
Yes
Yes
NS
NS NS Coached Coached NS Self NS Recorded
NS NS Amateurs All levels NS All levels NS Amateurs
NS NS Yes Yes NS NS NS Yes
NS NS NS Yes NS Yes NS Yes
NS NS NS NS NS Yes NS Yes
All levels
Yes
Yes
NS
11 minutes (mean duration) Not specified
Coached Self Recorded NS
Advanced NS
Yes NS
NS NS
NS NS
Customized to singer’s needs 5–10 minutes Not specified
Coached Self Self NS
All levels
Yes
Yes
Yes
Professionals NS
Yes NS
NS NS
NS NS
20–30 minutes
ARTICLE IN PRESS 4
Journal of Voice, Vol. ■■, No. ■■, 2017 VACCAI Metoda pratica de canto
PANOFKA 24 Vocalizzi, Op. 81
1.
The Scale
1.
Diatonic Scale
2.
Intervals of Fourths Intervals of Fifths
2.
Minor Scale
3.
Intervals of Sixths
3 4.
Agility
4.
Intervals of Sevenths Intervals of Octaves
5 6.
Thirds
5.
Semitones
7.
Legato (groups of two)
6.
Syncopation
8 12. Portamento
7.
Intervals of Octaves
13.
Dotted Notes (delle note puntate)
8.
Appoggiaturas (above and below) The Acciaccatura
14.
Syncopation
9.
Mordents (graduated exercises)
15.
Legato
10.
Turns (graduated exercises)
16.
Appoggiaturas, Turns, and Mordents
11.
Trill (introduction)
17.
Trills (introduction)
12.
Roulades
18.
Agility
13.
Glides (two methods)
19.
Trills
14.
On Recitative
20 21. Arpeggios
15.
Recapitulation (cumulative summary of techniques)
22 23. Chromatics
Intervals of Thirds
24.
Intervals
SKILLS ADDRESSED: Legato, Flexibility, Style, Musicianship INTERESTING FEATURE: the singer sings actual texts throughout method
SKILLS ADDRESSED: Legato, Flexibility, Style, Musicianship
FIGURE 2. Panofka—24 Vocalizzi, Op. 81.
FIGURE 1. Vaccai—Metoda pratica de canto. table of contents of each volume also are descriptive of the vocal skills addressed by each exercise. Figures 1–3 describe the table of contents for the volumes by Vaccai, Panofka, and Marchesi. Concone’s 50 vocalises cover largely the same set of skills as those of Vaccai, Panofka, and Marchesi, but Concone does not specifically categorize his exercises or label the specific purpose of each. It is also obvious, upon examination of these vocalizes, that the skills addressed are designed to prepare the singer for a specific genre: specifically, 19th century bel canto Italian opera, exemplified in the works of Gioacchino Rossini (1792–1868), Gaetano Donizetti (1797–1848), and Vincenzo Bellini (1801–1835). Interestingly, these three pillars of the bel canto repertory spent so much time composing that they wrote very little about singing or singing technique. It was up to methodologists like Concone, Vaccai, Marchesi, and Panofka to lay a pedagogical foundation. Geared almost entirely toward skill acquisition, these historical vocalises were designed to give singers the tools they need to perform this very specific repertoire, thus recognizing the need for specificity before that principle was ever formally described. In these historical vocalises, extra-technical considerations, such as musicianship and style, were also addressed, albeit peripherally. Although flexibility and evenness of the voice
throughout the range were routinely addressed, specific strategies for resonance and breath management were not explicitly discussed. This historic “international Italian” approach, which has been synonymous with voice pedagogy for two centuries, reached its zenith within the American school of voice pedagogy through two works by Richard Miller, arguably the most influential voice pedagogue of the second half of the 20th century. Miller’s first book, English, French, German, and Italian Techniques of Singing: A Study in National Tonal Preferences and How They Relate to Functional Efficiency (1977),35 was profoundly influential in convincing American pedagogues that Italian methodology was technically superior to alternative approaches, particularly in the area of breath management, advocated by Miller through the appoggio technique. His follow-up effort was The Structure of Singing (1986),7 a comprehensive and systematic approach to skill acquisition rooted in the Italian school. An examination of its table of contents (see Figure 4) demonstrates this work’s firm lineage and relationship to the 19th century methodologies listed above. Unlike the historical works, however, Miller also included commentary: he explains the purpose of each vocalise presented, and more importantly, described the basic physiology and rationale beyond the exercise and its place within the sequence. The
ARTICLE IN PRESS Matthew Hoch and Mary J. Sandage MARCHESI PART I
5
Implications for Singing Voice Pedagogy Op. 31
Elementary and Progressive Exercises
pratique, Op. 31
MARCHESI PART II
Development of the Exercises
1.
Emission of the Voice (attack)
1.
Attack
2.
Chromatic Slur
2 7.
Portamento
3.
Diatonic Slur
8 9.
Sostenuto
4 8.
Portamento
10 19.
Diatonic Scales
9 36.
Scales
20 21.
Dotted Diatonic Scales
37 73.
Exercises for Blending the Registers
22.
Minor Scale
74 125.
Exercises on Two, Three, Four, Six, and Eight Notes
23 25.
Major and Minor Scales (alternating)
126 135.
Chromatic Scales
26 27.
Chromatic Scales
136 137.
Minor Scales
28.
Repeated Notes
149 151.
Varied Scales
29.
Triplets
152 153.
Repeated Notes
30.
Arpeggios
154 162.
Triplets
31.
Appoggiatura and Acciaccatura
163 173.
Arpeggios
32.
Mordent and Turns
174.
Messa di Voce
33.
Syncopation
175 192.
Appoggiaturas, Acciaccaturas, Mordents, Turns
34.
Long Intervals
185 192.
Trills.
35.
Staccato, Mezzo-Staccato, and Accented Notes
36.
Trills
SKILLS ADDRESSED: Legato, Flexibility, Style, Musicianship INTERESTING FEATURES: Register blending, messa di voce mentioned
FIGURE 3. Marchesi—Method de chant théorique et pratique, Op. 31. influence of The Structure of Singing on modern voice pedagogy cannot be understated: more classical teachers teach like Miller than anyone else, and Miller’s concepts permeate modern voice pedagogy curricula. In his proposal of specific vocal warm-ups,15 Titze not only promotes a new generation of skill acquisition exercises, but also explains the scientific rationale behind each—they are designed to promote vocal efficiency as opposed to only being geared toward singing a specific kind of literature. Figure 5 outlines Titze’s warm-ups. Titze’s interest in muscle physiology suggests a “next step” for voice teachers interested in going beyond skill acquisition for skill acquisition’s sake. For singing teachers to better understand basic muscle physiology and training up their singers for specific tasks, exploring exercise science principles can be a fruitful avenue. There is a long and widely held belief that vocal warm-up is important for singers for both performance quality and vocal health. However, the physiological mechanisms for these benefits are not well understood. Within the exercise science literature, warm-up exercise that targets skill acquisition and trains fatigue
resistance is attributed to injury prevention.2 A few recently published pedagogical resources addressed skill acquisition and fatigue resistance specifically, but with little discussion devoted to the topic of injury prevention. More current resources that include the concepts of skill acquisition and fatigue resistance include Reid,19 Miller,7,20,21 Elliot et al,24 David,36 Sell,27 Amir et al,28 and Gish et al.30 Although fatigue resistance was not an explicit goal of these warm-up approaches, the longer warmup times recommended may result in upregulation of those physiological mechanisms that promote fatigue resistance. It is apparent from this review that attention to the specific benefits of vocal warm-up is a more recent consideration in the planning and execution of vocal warm-up. A little-discussed aspect in the traditional classical pedagogy texts and the published literature to date are the muscle physiology implications of muscle bioenergetics with regard to type and duration of singing warmup. Consideration of exercise science principles, particularly in the area of muscle training and skill acquisition, can be invaluable when assigning vocal warm-ups, and these vocalises should be thoroughly grounded in the specific repertoire that the singer will perform. Integrating these principles into one’s teaching
ARTICLE IN PRESS 6
Journal of Voice, Vol. ■■, No. ■■, 2017 MILLER
The Structure of Singing (1986)
TITZ
1.
-UPS (2000)
Lip trill, tongue trill, humming, or phonation into narrow
1.
Onset and Release
2.
Breath Management
tubes (all partial occlusions of vocal tract) on glides, scales,
3.
Agility/Flexibility
or arpeggios.
4.
Resonance
2.
Two-octave pitch glides, up and down, high vowels /i/ or /u/.
5.
Vowel Balancing
3.
Forward tongue roll and extension, vowel sequence /a/ /i/,
6 7.
Resonance (nasal and non-nasal consonants)
8.
Sostenuto
scales. 4.
high vowels, to low vowels.
9 10. Registration (male and female) 11.
Vowel Modification
12.
Range Extension
13.
Messa di voce and Dynamic Control
14.
Vibrato and Vocal Timbre
15 17. Extra-Technical Concerns
PRINCIPAL FEATURE: Detailed prose accompanies specific exercises.
FIGURE 4. Miller—The Structure of Singing (1986). routine encourages successful outcomes when honing specific aspects of singing technique. Untangling these various aspects of vocal technique through assessment rubrics can also prove to be invaluable. REFERENCES 1. Vaccai N. Practical Method of Italian Singing: For Soprano or Tenor. G. Schirmer; 2000. 2. Concone G. 50 Lezioni op. 9. Milan: Bertelsmann Music Group; 2005. 3. Panofka H. Vocalizzi. Milan: Bertelsmann Music Group; 2006. 4. Marchesi M. Marchesi Vocal Method, Op. 31. New York: Schirmer; 1986. 5. Vennard W. Singing: The Mechanism and the Technic. Carl Fischer, LLC; 1967. 6. Appelman DR. The Science of Vocal Pedagogy: Theory and Application, Vol. 378. Indiana University Press; 1967. 7. Miller R. The Structure of Singing: System and Art in Vocal Technique. Wadsworth Pub Co; 1986. 8. Brooks GA, Fahey TD, Baldwin KM. Exercise Physiology: Human Bioenergetics and Its Applications. 4th ed. Boston: McGraw-Hill; 2005. 9. Pearce AJ, Rowe GS, Whyte DG. Neural conduction and excitability following a simple warm up. J Sci Med Sport. 2012;15:164–168. 10. McArdle WD, Katch FI, Katch VL. Exercise Physiology: Nutrition, Energy, and Human Performance. Lippincott Williams & Wilkins; 2010. 11. Powers S, Howley E. Exercise Physiology: Theory and Application to Fitness and Performance. 9th ed. Boston: McGraw-Hill; 2014. 12. Sandage M, Smith A. Muscle bioenergetic considerations for intrinsic laryngeal skeletal muscle physiology. J Speech Lang Hear Res. 2016. 13. Witvrouw E, Mahieu N, Danneels L, et al. Stretching and injury prevention: an obscure relationship. Sports Med. 2004;34:443–449. 14. Sale DG. Influence of exercise and training on motor unit activation. Exerc Sport Sci Rev. 1986;15:95–151. 15. Titze IR. Vocal warm-ups: what do they accomplish? J Acoust Soc Am. 2000;107:2864.
Messa di voce, proceeding from a partially occluded tract to
5.
Staccato on arpeggios.
NOTE: Specifically geared toward muscle training and coordination.
FIGURE 5. Titze’s five favorite warm-ups (2000). 16. Lamperti GB. Vocal Wisdom: Maxims Transcribed and Edited by William Earl Brown. New York: Taplinger; 1931. 17. Kagen S. On Study Singing. New York, NY: Dover Publications; 1950. 18. Bunch M. Dynamics of the Singing Voice. Springer; 1982. 19. Reid CL. A Dictionary of Vocal Terminology: An Analysis. Joseph Patelson Music House; 1983. 20. Miller R. Warming up the voice. NATS J. 1990;46:22–23. 21. Miller R. On the Art of Singing. USA: Oxford University Press; 1996. 22. Sundberg J. The Science of the Singing Voice. DeKalb, IL: Northern Illinois UP; 1987. 23. Doscher B. The Functional Unity of the Singing Voice. Scarecrow Press; 1993. 24. Elliot N, Sundberg J, Gramming P. What happens during vocal warm-up? J Voice. 1995;9:37–44. 25. Ware C. Basics of Vocal Pedagogy: The Foundations and Process of Singing. McGraw-Hill; 1998. 26. Blades-Zeller E. A Spectrum of Voices: Prominent American Voice Teachers Discuss the Teaching of Singing. Scarecrow Press; 2002. 27. Sell K. The Disciplines of Vocal Pedagogy: Towards an Holistic Approach. Farnham, Surrey: Ashgate Publishing; 2005. 28. Amir O, Amir N, Michaeli O. Evaluating the influence of warmup on singing voice quality using acoustic measures. J Voice. 2005;19:252–260. 29. Smith WS, Chipman M. The Naked Voice: A Wholistic Approach to Singing, Vol. 1. Oxford University Press; 2007. 30. Gish A, Kunduk M, Sims L, et al. Vocal warm-up practices and perceptions in vocalists: a pilot survey. J Voice. 2012;26:e1–e10. 31. McCoy SJ. Your Voice, an Inside View: Multimedia Voice Science and Pedagogy. 2nd ed. Inside View Press; 2012. 32. Coffin B. Overtones of Bel Canto: Phonetic Basis of Artistic Singing: With 100 Chromatic Vowel-chart Exercises. Scarecrow; 1980. 33. Coffin B, Delattre P. Sounds of Singing, Metuchen. NJ: Scarecrow; 1987. 34. Miller R. Solutions for Singers: Tools for Performers and Teachers. Oxford University Press; 2004. 35. Miller R. English, French, German and Italian Techniques of Singing: A Study in National Tonal Preferences and How They Relate to Functional Efficiency. Scarecrow Press; 1977. 36. David M. The New Voice Pedagogy. 2nd ed. Lanham, MD: Scarecrow Press; 2008. 37. Milbrath RL, Solomon NP. Do warm-up exercises alleviate vocal fatigue?. J Speech Lang Hear Res. 2003;46:422–436. 38. Wicklund K. Singing Voice Rehabilitation: A Guide for the Voice Teacher and Speech-Language Pathologist. Boston: Cengage; 2009.