Correct Breathing and 'Support' for Singing
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It seems as though everyone knows that breathing technique is important to singing. Even people who have never taken a voice lesson before have heard that there is a correct way for singers to breathe, although they may not know what that way is. They may have been told that 'diaphragmatic breathing' is essential to good singing, but they may not understand why.
Sadly, the proper mechanism of breathing largely remains a mystery to both the untrained singer and the singer-in-training alike. 'Breathe from the diaphragm' and 'support the tone' are phrases that often get thrown about carelessly within pedagogic circles. The assumption is that the student will instantly understand what these vague suggestions mean and be able to successfully apply them to his or her singing. An equally faulty assumption is that the vocal teacher himself understands these expressions and knows how to convey their meaning to his students. Unfortunately, not all teachers have a good grasp on what is involved in proper breath management, either, and they thus cannot help their students achieve mastery of their breath for singing, except by sheer coincidence.
Before going any further in this article, I would like to offer a warning for those singers who are trying to understand how to properly support their voices during singing: Not all teachers understand it themselves, and not all singing instructors teach good or safe methods. In this article, I will also describe some errant methods of managing the breath and explain why these techniques are unnatural to the body, unhealthy, and ineffective - why they violate the natural functioning of the body and do not produce desirable results.
Good breath management skills are imperative if a singer hopes to be able to sound great and to sing with skill. Understanding how breath management either positively or negatively impacts various elements of the voice's quality may help to make good breath support seem more logical and advantageous.
The results of proper breathing technique may include better control over the breath and thus the quality of the voice's tone, more efficient use of the breath resulting in less breathiness or 'airyness' in the tone, the ability to sustain notes for considerably longer and to sing longer phrases, increased lung capacity, a natural (unforced) increase in volume, improved overall stamina or endurance, minimized tension in the chest, shoulders, neck and face, less pressure on the vocal folds, and better oxygenation of the entire body.
The Physiology of Breathing
Breathing is an action that is regulated by the autonomic nervous system, which works to maintain homeostasis, or balance, in the body. In the case of breathing, it helps to regulate the proper input of oxygen and balance of carbon dioxide.
The diaphragm - a shelf of muscle and tendon that extends across the bottom of the ribcage – responds to various signals from the nervous system. When we inhale, the diaphragmatic muscles contract - they shorten and tighten - and the diaphragm moves downward in the body. As the diaphragm depresses, it creates a vacuum in the lungs and air rushes in to fill that vacuum. During exhalation, the diaphragm relaxes and rises, and lung volume decreases, creating a positive pressure difference, and air rushes out. The air expelled from the lungs rises up through the trachea (wind pipe) and filters out through either the nose or the mouth. (When air meets resistance at the laryngeal level – that is, when the vocal folds are approximated – sound, or voice, is produced.)
Most of the actions of the autonomic nervous system, such as respiration rate, heart rate, digestion, salivation, perspiration, dilation of the pupils, urination and sexual arousal, are involuntary – performed without conscious control – but some, including breathing, work in tandem with the conscious mind. In other words, we can actively control our breathing, stopping it and starting it at will, choosing how much air we will inhale or exhale in a given breath or deciding how rapidly or how slowly we will perform each phase of the breath cycle, for instance. This makes it possible for us to actively develop our breathing skills and to enhance them for the extended duration and intensity of singing tasks (as compared with the duration and intensity of speaking tasks). The various dynamics and demands of singing make the development of breath management technique and skills absolutely necessary.
How is the physiological mechanism of breathing relevent to singers? Essentially, the breath fuels the voice. The breathing mechanism is the voice's 'motor', providing energy to the tone and the ability to sustain passages or notes. Without the diaphragm and the surrounding muscles that support its work - there are thirty-six muscles that are used in breathing for singing - air can neither enter nor leave the lungs. Without the expelling of air from the lungs that moves its way upward and out of the body via the system of tubes in our chest, neck and head, the vocal folds can’t vibrate. (It is the air passing between the closed vocal folds that causes them to oscillate and buzz.) Without the vibration of the vocal folds, sound - or voice - isn’t produced.
Singing and speaking are little more than breathing out the noise made in the 'voice box', or larynx. (To learn more about the physiological mechanism of breathing, read Anatomy of the Voice.) However, how we approach breathing - the techniques that we use or apply - makes a significant difference in the quality and skillfullness of that voice.
At first, most vocal students view breath management as a difficult, unnatural activity that they must somehow attempt to do while trying to sing, as though the two are separate tasks that they must train themselves to do simultaneously, like rubbing their stomachs while patting their heads, rather than the very activity that enables them to produce quality sound and thus sing skillfully. For these students who don’t tend to understand the important connection between the air that they use and the sound that they make, it requires a great deal of concentration to breathe correctly and effectively while vocalizing, and they may struggle for some time to understand how to achieve the desired results. In time, breath management will become more natural and automatic.
It is important to note that the difference between how we breathe for singing and how we breathe for other daily activities lies not in the mechanisms but in how we regulate our airflow, because the demands that our bodies have for air changes with different activities. Although it is still in accordance with the natural functioning of the body, 'natural breathing' as employed for speech is not adequate for intense singing demands. During normal demands, such as speaking or resting, we tend to inhale and exhale more shallowly and evenly because our bodies don’t require as much oxygen. Air is exchanged in cycles of approximately four to six seconds; this differs slightly from person to person, of course. During singing, however, we need to inhale quickly and deeply, then exhale slowly and steadily, in a long breath, as we sing our phrases or notes.
Singing requires a higher rate of breath energy than speaking does, as well as the elongation of the breath cycle. (The rate of expiration has to be retarded beyond that appropriate to speech, especially during passages or notes of durations greater than the normal 'at rest' breath cycle.) This higher need for energy and stamina requires more muscle control and coordination in supporting the work of the diaphragm and the function of the larynx, and this is the part of breathing that needs to be developed through training. Learned controls must be mastered in order to extend breath management capabilities. Students of voice need to learn how to extend the normal breath cycle by remaining in the inspiratory position for as long as possible, maintaining a raised sternum (but not raised shoulders or clavicle), no (or minimal) chest displacement, allowing the muscles of the lateral abdominal wall to stay close to the position of inhalation and delaying early ribcage collapse. (More about this technique can be read in Appoggio, below.)
While the applied method, means or approach to achieving 'breath support' may differ slightly from person to person depending on training, technique and genre or style, most teachers and singers seem to share a general concept or definition. 'Support' is a way of using other parts of the body (e.g., muscles) connected to the work of the lungs and larynx to produce the desired results, including better tone production and the ability to sing extended phrases and sustain notes for longer. The successful connection between the musculature of the body (the abdomen and back primarily) and the larynx (for sound and tone production) is often referred to as 'support', 'breath support' or 'supporting the tone'. Many teachers, including myself, prefer to call how a singer uses the lower body to regulate airflow based on his or her immediate vocal demands 'breath management', which suggests a deliberate and successful coordination or skillful directing of attention and energy toward the work of breathing.
There are two important aspects of breath management: 1) regulating the amount of air that is pushed past the vocal folds, including the pace at which the air is allowed out of the lungs, and 2) ensuring that the stream of air is steady. As I will explain below, in the section entitled Appoggio, the most efficient way of supporting the tone or managing the breath is by allowing the diaphragm to rise slowly, using the muscles of inhalation, so that a mininal and steady stream of air can be allowed past the vibrating folds.
Support works by contracting the abdominal muscles, creating higher pressure in the abdomen and thorax, allowing the diaphragm's relaxation (and upward rise) to be more carefully controlled. There is less control in relaxing a muscle than there is in contracting it, so support gives performers a means of controlling their sound, or phonation.
Today, there are two main schools of teaching about the breath, although there are many different approaches: (1) 'supporting' the breath by compressing the abdomen during phonation (i.e., on the exhalation), or (2) relaxing the abdominal muscles as much as possible during inhalation and phonation, allowing the diaphragm to work on the inhalation, and riding its relaxation on the outgoing breath (i.e., during phonation).
The extent to which action of the ribs is encouraged varies within most techniques, although most teachers, including myself, recommend that the upper torso, especially the shoulder girdle, be as relaxed as possible even during the most extreme vocal demands. Ultimately, a singer wants access to all the "breath resources" available without jeopardizing the ability to freely produce sound, that is without unnecessary tension.
Probably the most commonly used term in vocal pedagogy and amateur singing circles is 'breathing from the diaphragm'. The implication is that the diaphragm itself controls airflow and supports the tone of the singing voice, and the assumption is that we can learn to actively control the diaphragm's movements.
Take note, however, that during singing, the diaphragm is not consciously engaged as a means for pulling in new breath, nor is it used to drive air upward for the expulsion of breath. Also, the diaphragm itself is actually passive during singing, which occurs during the exhalation phase of breathing, and we do not exert active control over its movements. (In breath management for singing, we learn to actively control the muscles that interact with the diaphragm and that support its actions.)
These anatomical truths make the term 'diaphragmatic breathing' a little bit misleading, or at the very least, a misnomer. The expression may allow too much emphasis to be placed on the diaphragm, an organ that we cannot consciously control, when it is really the muscles of the torso that we must develop and learn to control during singing. (However, if we were to use the term 'muscular breathing' instead, we would probably find many singers attempting to push their voices out of their bodies with too much muscular force, as is taught and practiced in 'belly breathing'.)
Also, the diaphragm is involved in all breathing, whether correct, efficient and effectively regulated or not, again making use of the expression 'diaphragmatic breathing' almost superfluous. For these reasons, singers and teachers might be better served by using the terms 'breath management' or 'appoggio', (which is a technique whereby singers slow the rise of the diaphragm by actively controlling the back and abdominal muscles that act upon it), instead.
In any case, the diaphragm, in cooperation with the intercostals (back) and abdominal muscles, is generally considered to be the chief organ of breathing. The movement of the diaphragm sets off a chain of reactions that occur in the lungs, larynx and mouth or nose. Again, it is really the muscles that support the diaphragm’s work - the intercostals being involved primarily in inhalation and the abdominal muscles in exhalation - that are the focus of a singer’s training in effective breath management. Therefore, 'diaphragmatic breathing', although a vague term, should not be completely dismissed.
In most cases when someone is using the expression 'breathe from the diaphragm', it seems to be understood that expansion of the area just beneath the diaphragm and using the abdominal muscles is what is necessary in order to support the singing voice.
Many people tend to think of diaphragmatic breathing as something unique to singing; as a special skill that must be taught to them, rather than the body’s natural way of working. However, the fact of the matter is that we are born knowing how to breathe properly, and no one has to teach us how to do it when we come out of the womb. The tummies of sleeping babies rise and fall effortlessly, without any tension or movement in their chests and shoulders. The parts of their bodies that support their breathing work in effortless coordination and synchronicity. Even the breathing of adults is correct when they are relaxed or asleep and not actively trying to control it. The body naturally knows what to do and how to do it, even when our need for oxygen is greater due to increased physical activity or in response to boosts of adrenaline (as when we are frightened).
The fact that 'diaphragmatic breathing' is both natural and ideal is why so much emphasis is placed on 'breathing from the diaphragm' while singing. Breathing in this natural way - or at least using this natural mechanism as a starting point then learning to enhance it for the extended demands of singing - enables us to regulate our airflow, and is correct whether we are singing, exercising, speaking or watching television. Proper breathing for singing is not just a trick or a specialized skill that singers must learn. It is a product of the natural functioning of the human body. In other words, it is how our bodies have been designed to take in and expel air. In breathing for singing, the mechanism of breathing is not an abberation from that of the breathing technique used by the body during other acitivities.
It is also important to note that, in voice pedagogy, 'breathing from the diaphragm' and 'breathing from the belly' are not viewed as being synonymous. The breath support technique that is widely referred to as 'diaphragmatic breathing', (when correctly executed), should not be confused with 'belly breathing'. Unlike 'belly breathing', 'breathing from the diaphragm' involves no pushing or forceful expulsion of air, and is the natural, correct, safe, gentle, internationally accepted method of supporting the singing tone. In diaphragmatic breathing, the tone rides on a minimal and steady stream of air, which brings stability and consistency to the tone.
The reason why diaphragmatic breathing is sometimes, though inaccurately, called 'breathing from the belly' is because the bulk of the movement that is seen while someone is breathing naturally occurs in the abdominal and lower rib area. When the diaphragm moves downward, it creates a little less room in the abdomen for the internal organs, which forces them to move outwards a little and the belly to distend or 'swell'. (This action is aided by the muscles of inhalation.) This movement is so noticeable because of the absence of ribs in this area, which would otherwise hold the belly in like a girdle of bone, restricting the diaphragm’s movement. Allowing the movement of our bodies during breathing to be focused in the soft, fleshy area below the diaphragm encourages the more efficient and complete filling of the lungs and allows for a good connection to be made between the diaphragm and the 'support muscles'. (Again, the actual decent of the diaphragm is minimal - two inches or less - and this abdominal distension need not be exaggerated.)
Understand, though, that the belly itself doesn’t actually breathe, as the lungs are located above the belly and the diaphragm. It merely moves in response to the diaphragm’s downward and upward movements and to the expansion and contraction of the support muscles.
There is one particular self-professed “vocal release method” expert who criticizes the diaphragmatic breathing technique, telling those who read his website and purchase his singing course that diaphragmatic breathing was created by a failed opera singer who later became a teacher and passed on his "dangerous" breathing technique to others. He explains that this erroneous teaching has infiltrated the entire classical singing world, and has caused a great deal of damage to singers, utterly destroying their vocal health and careers.
Unfortunately, this vocal coach has had some bad teachers of his own in the past – he openly writes about his experiences with unsuccessful vocal training on his website - and was never given any solid instruction in what diaphragmatic breathing really is, nor what appoggio technique is. He, like many others, has confused it with pushing or 'belly breathing', which involves excessive muscular involvement deep and too low in the body during the exhalation phase of breathing. This pushing technique forces too much air pressure to blow past the vocal folds at once, which can indeed injure the vocal instrument.
While useful for some vocal tasks, and always correct and safe, this 'natural' breathing is somewhat limiting when it comes to more demanding singing tasks. Although it may suffice for short phrases that allow for frequent breath renewals between them, (as is common in contemporary genres and styles of music), it is not necessarily adequate for more intense vocal tasks, (as in the longer phrases or passages, sustained notes, or high lying tessituras that are more common in classical vocal literature). Without violating the same natural functioning of the body's breathing mechanism, elite singers must learn to enhance their breath management techniques beyond 'diaphragmatic breathing' in order to skillfully execute challenging vocal lines. This is why appoggio was developed, and why so many elite singers use it today to help support their breath.
Oftentimes, the terms 'diaphragmatic breathing' and 'breathing from the belly' are used interchangeably by those who are unfamiliar with singing pedagogy terms or who use them very loosely. However, diaphragmatic breathing should not be confused with the dangerous technique known as 'belly breathing', in which singers expand all areas of the torso, right down to the pelvis, and then use excessive muscular force as they exahale.
This faulty technique may be reinforced by teachers who instruct their students to expand their entire abdominal area through to the hypogastric (pelvic and lower abdominal) region rather than just the epigastric area – the area between the bottom of the sternum and the navel and extending outward to the lower part of the ribs on each side. This particular technique, called Bauchaussenstütz, has its origins in the German school of singing.
Some misguided and ill-informed teachers will have their students place their hands below their navel when practicing their breathing exercises or singing. The incorrect assumption is often made that greater expansion of the lower torso means a lower diaphragm, which creates more room in the lungs and thus more capacity for air. Then, the student is led to believe that pushing upward and inward with the abdominal muscles upon exhalation (i.e., during phonation, or singing) allows more air out of the lungs, thus creating more singing volume or vocal 'power'.
Of course, these assumptions are not based on either logic or scientific fact. The diaphragm is not located in the umbilical and hypogastric regions of the body, and it is the area above, not below, the navel that should be seen to expand and contract during inhalation and exhalation. Also forcing air out rapidly more often than not leads to pressed or breathy tones, which are lacking in resonance balance, are limited in volume and dynamic variation, are potentially damaging to the vocal folds, and do not regulate the airflow efficiently.
This tendency of many singers to breathe 'too low' into their abdomens, unnecessarily expanding the entire area below the ribs is illogical. The central tendon of the diaphragm lies relatively high in the torso - approximately at the fifth rib - and is attached to the paracardium, in which the heart is housed. The diaphragm itself follows the lateral anterior contour of the rib cage. It does not extend very low – during inhalation, its descent is often less than two inches - and air does not occupy spaces below the lungs. The breath process cannot be controlled by the belly - there is no air below the lungs that needs to be moved upwards by the muscles of the pelvic region - yet because of what it connotes, using the subjective expression 'breathing from the belly' in place of 'breathing from the diaphragm' or 'appoggio' may produce flawed thinking and thus faulty and potentially injurious breath managment techniques in misled vocal students who lack correct scientific information.
Stretching or thrusting the lower stomach outward causes lower trunk and laryngeal tensions, as well as rising subglottic pressure by inducing excessive resistance to the exiting air, and may result in pressed phonation (forcing). Furthermore, pushing down on the abdomen causes the ribs to move inward and the sternum to fall. Lung volume will be diminished because contact of the abdominal musculature with the lower ribs is reduced. Belly breathing is, therefore, an inefficient and unhealthy way to approach breathing for singing, and should not be considered a viable method of achieving good support.
"Clavicular (Chest) Breathing" and "Upper Dorsal Breathing"
There are many singers who allow their shoulder girdles and clavicles to rise as they breathe. This is the kind of breathing that we tend to resort to when we are sighing or when we are winded and wish to rapidly fill our lungs with more air, something that has been termed "the breath of exhaustion".
This method of breathing causes chest displacement, collapsing of the sternum, and a loss of contact between upper and lower torso muscle groups. (Allowing only the ribs to expand and the lungs to remain high as they inflate not only prevents the lower lobes of the lungs from filling and moving downward, but it also makes it more difficult for the muscles that support breathing to do their jobs. The muscles that help pull the diaphragm downward during inhalation and those that move it upwards during exhalation need to work in conjunction with the diaphragm to promote optimal intake and expiration of air. These muscles are not as efficient on their own.) It is also noisy and laboured, and results in high rates of breath emission.
There should be minimal displacement of the chest during inhalation (including breath renewal) and during phonation. The rib cage should not collapse at the end of every phrase. Though the upper body should not remain rigid, it should retain its 'noble' position throughout the breath cycle.
'Tanking Up' or Inhaling Too Deeply
In a preemptive maneouvre to avoid running out of breath, many singers will inhale as much air as possible, without giving consideration to the length or the dynamics of the phrase or note that will follow the breath renewal. This kind of breathing often leads to an 'overcrowding' of the lungs and to rapid breath expulsion. (These same singers are often 'clavicular' breathers, who gasp for air between phrases in order to expel the remaining 'stale' air and inhale 'fresh' air, as though they've been holding their breath under water for a long time and are coming up to the surface.)
There is no need for a singer to inhale any more deeply than is necessary for the vocal task that will immediately follow the breath renewal. 'Tanking up' for long phrases leads to problems such as tensions throughout the body due to displacement of the chest and collapsing of the rib cage, forcing, noisy breathing, grabbing or holding the breath in advance of the next phrase. The gasping and rapid intake of air between phrases may also lead to hyperventilation, lightheadedness and dizziness.
Silent breath renewals, breathing slowly and quietly through the nose, are often helpful because they induce relaxation of the vocal tract and teach the student to pace the inspiratory gesture, as it takes longer to fill the lungs to capacity when inhaling through the nose. Furthermore, they help to minimize chest displacement. The same kind of noiseless and relaxed breath renewal can then be learned when breathing through the mouth, either fast or slow. (More about developing good breath pacing can be found in the Breathing Exercises section on the second page of this article.)
Appoggio – from the Italian verb appoggiare, meaning 'to lean on', 'to be in contact with' or 'to support' - is a learned breathing technique that involves slowing down the ascent of the diaphragm for better breath management, resulting in the elongation of the breath cycle during singing. It involves a concerted action on diaphragmatic movement by the muscles of the thorax (chest) and the abdominal wall (the transverse abdominis, the internal oblique, the external oblique, and the rectus abdominis, although to a lesser extent), and involves gaining better control over the breathing mechanism through training the muscles, and enables the singer to pace the breath more efficiently.
It’s important to note that appoggio, while requiring a great deal more control than is needed during normal activities and requiring some additional coordination and training, is an extension of the natural breath process, not a substitute for it. It is considered to be the main route for breath management within the international classical singing community.
During normal speaking, the rib cage collapses upon exhalation. Appoggio attempts to avoid this collapse by retaining the elevated inspiratory posture of the rib cage and the sternum – the long flat bone located in the centre of the thorax (chest), which connects to the rib bones via cartilage, forming the rib cage with them. The technique slows down the rising of the diaphragm, which aids in breath management. Learning to gain control over the muscles of the side abdominal wall offers true breath support.
Appoggio involves raising the sternum before inhalation, making all conscious breathing efforts with the internal and external obliques and transverse abdominis, then keeping the sternum up and not allowing the chest to recoil when replenishing the air supply. (This is sometimes called 'sideways inhalation'.) One method of achieving this ideal elevated sternum posture involves raising both arms above the head - the sternum naturally rises when the arms are in this position - suspending, but not holding, the breath with the inspiration muscle system, then lowering the arms while exhaling slowing without lowering the sternum. Assuming the Garcia position, with the palms facing outward and placed one on top of the other on the sacrum - not the small of the back, which could cause the back to 'sway' and become overly arched - while vocalizing can also encourage an opening of chest wall with a raised sternum.
If applied appropriately, simulating the posture of breath retention can minimize subglottic pressure. At inspiration, subglottic pressure is at its lowest level and lung volume is at its highest. The lowering of the diaphragm and the widening of the lower ribs causes the dimensions of the thoracic cavity to increase in both length and width. Due to its incredible elasticity, the entire respiratory tree stretches downward with the descent of the diaphragm, allowing for greater lung capacity, as the lower lobes of the lungs are now able to be filled. (Pushing upward with the abdominal wall and forcing the diaphram upward compresses the lungs and decreases their capacity.) Staying in the position of initial inhalation gives the singer the sensation of 'singing on the gesture of inhalation' - we do not inhale as we sing, but we are merely making the gesture, or retaining the same posture - rather than on that of exhalation, which retards breath exit, and in turn retards the return to atmospheric pressure and minimizes mounting subglottic air pressure.
In singing, (as well as in the Italian language itself), the term 'appoggio' has both a passive component and an active connotation, and may vary with different technical approaches. For some singers, breath flow pressure becomes a self-sustaining system whereby the singer feels the breath pressure in the body as an influence of stability. The diaphragm remains relaxed and is acted upon rather than being active. Others, however, might say that they consciously push down against the pressure of the breath. In that way, they are actively trying to find something to 'lean on', to use as a support. (I find that many of my students initially experience the latter sensation, in which they are more aware of the sense of pressure in their abdominal, side and back muscles, and then gradually begin to find the technique easier, more natural and more beneficial over time as their muscles become stronger and better coordinated with what is happening in their larynxes.)
Inhalation should be accompanied by a sense of expansion or 'fullness' in the epigastric area, as well as a sense of expansion of the lower ribs. This rib expansion is caused by the contraction of the external intercostal muscles, and should be felt during any substantial inhales. In addition to expansion at the base of the ribs, it can be felt at the front and sides of the torso, between the tenth rib and the crest of the iliac (upper surface of the hipbone) and in the back at the eleventh and twelfth ribs. The wider the rib opening and the longer this expansion can be maintained, the greater the downward hydrostatic pressure and the greater the pull against the elevation of the diaphragm. Lateral abdominal expansion will eventually equal or even exceed the expansion of the front part of the abdomen when the appoggio system is developed and applied. Consequently, this rib expansion is the effect that is typically most noticeable to the singer.
At the height of inhalation, when the singer is breathing deeply and the lower torso is expanded laterally, dorsally and frontally, he or she will likely also feel a sense of 'suspension', in which it feels as though the voice is sitting or resting on something, or a feeling of 'buoyancy'. When he or she begins to sing, this same feeling should be maintained for as long as is comfortable, with the sternum still elevated, the epigastric area still comfortably 'full' and the lower ribs expanded. (It is this position that prevents the diaphragm from rising upward too quickly.) The abdominal muscles should be relaxed, and the singer will find the necessary exhalation will occur without the singer having to be overly concerned about the action of the muscles in the abdominal area. As he or she arrives at about the last third of the exhaling breath, the epigastric area will naturally move slightly inward, but he or she should attempt to keep the lower ribs in as outward a position as possible, without thrusting the muscles outward or downward. This is a learned response that will help retard the ascent of the diaphragm or avoid its early rise.
This lower rib expansion and the epigastric 'fullness' which, in turn, create the feeling of inspiration suspension, is "appoggio".
At first, it may seem as though you are not getting enough air, especially if you are accustomed to hyperextending the support muscles then thrusting them upward and inward as you sing, but you will soon find that your air supply is indeed sufficient to complete your singing tasks, even long phrases, because the diaphragm is rising slowly and pacing the exit of the air to make it last for the duration of the tasks. You will get stronger and more adept at controlling and maintaining this lower rib action.
Acquiring the appoggio breathing technique gives the singer a longer, more reliable air supply (because the exiting air is pragmatically paced in order to meet the requirements of extended phrases, regardless of tessitura or dynamic level), greater stability of tone (because tone is affected enormously by the steadiness of a singer’s breath stream), easier execution of large intervals, improved agility, including greater clarity, accuracy and speed while singing technically challenging passages, and better breath management when singing very softly or quietly. Appoggio ensures that there is neither excessive airflow, (because most of the exiting breath is turned into tone by the efficiently vibrating larynx), nor too much resistance by the vocal folds to the exiting air (la lotta vocale).
Breath Support During Pregnancy
Depending on how a woman is 'carrying', pregnancy may affect how a female singer supports her voice, both in speech and in singing. In fact, pregnancy may present the only legitimate 'excuse' for reverting to thoracic (chest) or upper dorsal breathing because the size of the womb and unborn baby may make it difficult, if not impossible, to allow for free movement of the diaphragm and abdomen, especially if the woman is 'carrying high' and the fundus (top) of her uterus is placing pressure on and crowding the diaphragm and stomach. (A woman who is 'carrying low', on the other hand, may find that she is able to continue employing the same breath management techniques throughout her pregnancy.)
Additionally, the rectus abdominus (main abdominal muscle) typically separates later in pregnancy to allow for more room for the growing baby, which may create support challenges, especially post-partum. Also, the hormones of pregnancy may cause severe breathlessness as well as swelling of the capillaries of the vocal folds, which may pose more problems with supporting the tone.
For more information about the unique challenges that pregnant singers face, as well as practical advice for dealing with those challenges, please read Singing While Pregnant.