Many singers engage in some form of daily routine or warm-up prior to singing; however, many singers do not know the rationale behind choosing various warm-ups or their actual function. Unfortunately, these questions also elude researchers. A study by Elliott, Sundberg, & Gramming (1995) attempted to determine if vocal warm-ups prior to singing yielded the same effect as warming up other parts of the body, i.e., increasing blood flow to muscles thereby decreasing their thickness and increasing their pliability. Although the results of this study were inconclusive as to the exact effect of vocal warm-ups, several reasons still support the use of vocal warm-ups. Elliott, Sundberg, & Gramming emphasized that changing pitch undoubtedly stretches the muscles. They also noted that many singers subjectively indicated improved vocal functioning following warm-ups.
Warm-ups should not be confused with vocalises. Warm-ups, as in weight training, are used to stretch the muscles to prepare them for work without injury. Vocalises are tasks aimed at acquiring a particular skill, i.e., the actual exercise itself. For example, some schools of thought encourage simple, quiet glides across the range as an effective warm-up. On the other hand, using a staccato (short) "ha-ha-ha" on 1-3-5 of a scale is to encourage onset and flexibility. Many singers will use a variety of vowels, consonants, or arpeggios to "warm" the voice; however, these techniques may actually be encouraging articulatory precision or vowel balancing as in rapid "me-may-mah-mo-mu," or balancing "registers" as in sung single vowels on 1-5-6-5-1, etc.
Although unfortunately and frequently ignored, vocal cool-downs may also be used to prevent damage to the vocal cords. During speaking and singing, blood flow to the larynx is increased. Stopping immediately after prolonged speaking or singing may contribute to a pooling of blood in the larynx, weighing the vocal cords down. Damage may result as one attempts to speak on these potentially swollen folds. An analogy can be drawn to other physical exercise. After running for prolonged periods of time, an athlete is encouraged to walk for several minutes to maintain blood flow and prevent cramping. The same propensity for "cramping" may apply to laryngeal activity. The simple practice of gentle, relaxed humming can serve as an excellent form of cooling-down.
Once "warmed," the singer may proceed to daily exercises. The work of Sabol, Lee, & Stemple (1995) explains that many of the exercises prescribed for vocal flexibility are actually calisthenic exercises. Other exercises focus on training the perception of various resonances. A teacher may also recommend the use of isometric exercise, that focuses on improving vocal functioning at the level of the vocal cords. Vocal Function Exercises, first described by Barnes and modified by Dr. Joseph Stemple, are "a series of direct, systematic voice manipulations (exercises), similar in theory to physical therapy for the vocal folds, designed to strengthen and balance the laryngeal musculature, and to improve the efficiency of the relationship among airflow, vocal fold vibration, and supraglottic treatment of phonation."
Optimally, one should hear an example of Dr. Stemple's Vocal Function Exercises to ensure accuracy and efficiency. Most speech-language pathologists are familiar with the exercises, but a compact disc featuring examples of the Vocal Function Exercises is at Plural Publishing.
The Vocal Function Exercises should be done twice in a row, two times per day. They should be produced as softly as is possible with an easy onset (initiation of sound) and forward placement of the tone (avoid a swallowed or dark vocal sound).
Sustain the vowel sound "eee" for as long as possible on the musical note F above middle C for women, below middle C for men. The tone should be produced as softly as possible, but without breathiness. A good supported breath should proceed voice. The "eee" should be produced with an extreme "forward" tone focus; almost, but not quite nasal. The goal is to sustain the sound without breaks for as long as possible. Sustain an "eee" as long as possible.
Glide from your lowest to your highest note on the word "knoll" or on a lip or tongue trill. Voice should be soft, and a forward focus used. If breaks occur, continue to glide without hesitating.
Glide from a comfortable high note to your lowest note on the word "knoll" or on a lip or tongue trill. Voice should be soft, and a forward focus used. If breaks occur, continue to glide without hesitating.
Sustain the musical notes C-D-E-F-G, each as long as possible on the word "ol" ("old" without the "d"). Lips should be rounded; a sympathetic vibration should be felt on the lips.