10 PROVEN WAYS TO IMPROVE BREATHING:
STUDIES FROM THE SCIENTIFIC FIELD
Will Kimball, Brigham Young University
Breathing concerns are common among musicians. For vocalists, woodwinds, and brass, breathing technique is a major part of what we do in performance. While many of the breathing ideas and exercises created by musicians to improve breathing are beneficial, others may be a waste of time, or even detrimental to performance. The unique approach of this article is the attempt to summarize only points that have been tested and documented to affect measurable lung capacity, function, or mechanics. I have made a deliberate effort to document thoroughly, using only medical sources. A number of the medical articles are available online, free of charge, at www.pubmed.gov. If you see a source that you feel has been somehow discredited or improperly interpreted, by all means, please let me know.
A brief note about terminology: In the medical field, the term inspiration is synonymous with inhalation, and expiration with exhalation. Lung volume is divided into several categories, but vital capacity (the maximum amount of air a person can voluntarily exhale after a maximal inhalation), sometimes known as lung capacity, is the most applicable to musicians. Lung function refers to how well a person is able to use their lung volume (how quickly they can inhale or exhale, how much air they can move in a given amount of time, etc.). Although there are many different measures of lung function, the most common in the studies cited is forced expiratory volume in one second, or FEV1, the amount of air a person can exhale in one second. Spirometry is the practice of taking specific measurements of lung volume and lung function. Ventilation, which is probably a more exact term than breathing for the way air is used by musicians, is simply the movement of air in and out of the lungs (without respect to oxygenation of the blood, gas exchange, etc.).
1) Practice taking deep breaths
It has been shown that the respiratory muscles, like other skeletal muscles, can be strengthened through training (Belman and Sieck; Leith and Bradley; Roussos and Macklem). There is a whole subfield of respiratory therapy, called “incentive spirometry,” that is at least partially based on this idea as it applies to the respiratory system. Incentive spirometry involves, essentially, training respiratory muscles using various “mechanical aides,” especially those that offer “visual or other positive feedback” (AARP Guidelines). Practicing with these mechanical tools normally involves inspiration or expiration to full capacity or against varying degrees of resistance. Medical studies have shown that subjects practicing incentive spirometry on a daily basis for five to six weeks significantly improve both lung capacity and lung function, including vital capacity (Leith and Bradley), maximal dynamic pressure (Tzelepis “Inspiratory Muscle Adaptations”), maximal expiratory pressure (Nomori et al.; Do Hyun Nam et al.), maximal inspiratory pressure (Hart et al.; Nomori et al.; Do Hyun Nam et al.), and general inspiratory muscle performance (AARP Guidelines). My own personal experience with such training has yielded marked improvements in measurements of Peak Expiratory Flow and Forced Expiratory Volume in 1 second, but mixed results with vital capacity. For a more detailed explanation of the various breathing tools available and what medical studies have found in this area, the reader is directed to my article on respiratory training for musicians (here).
Studies have shown that measurable improvement can also result from practicing deep breaths without mechanical aides. In one study, a group of 16 healthy volunteers increased their vital capacity by an average of 200 ml by completing a daily six-week routine of 20 maximal inhalations, held each time for ten seconds with the glottis open (Fanta, Leith, and Brown). Similar studies, including both slow and fast breaths, as well as yoga-style breathing, have shown improvement in maximal inspiratory flow (Tzelepis et al. “Pressure-flow Specificity”) and peak expiratory flow rate (Joshi and Joshi; Nagendra and Nagarathna).
Generally speaking, it would appear that practicing breathing against resistance improves a person’s ability to exert respiratory pressures (which affects high register playing for brass), while practicing breathing without resistance (or against minimal resistance) increases the ability of the respiratory system to generate high flow rates (which affects loud dynamics in the middle and lower registers for brass) (Tzelepis et al., “Inspiratory Muscle Adaptations”; O’Kroy and Coast). Both types of practicing appear to benefit lung capacity (see above).
2) Eat fruit & vegetables
Multiple medical studies have found that intake of fresh fruit and vegetables directly improves breathing, including general lung function (Grievink et al.; Britton et al.), lung capacity (Grievink et al.), FEV1 (forced expiratory volume in one second) (Grievink et al.; Britton et al.; Butland et al.; Tabak et al. “Dietary Factors”; Tabak et al. “Chronic Obstructive”), and FVC (forced vital capacity) (Grievink et al.; Britton et al.). Fresh fruit has also been shown to have a protective effect on respiratory function from decline due to age (Grievink et al.). Apples (which contain high levels of the antioxidant quercetin) and vitamin E appear to have a particularly strong positive effect on lung function (Butland et al.; Tabak et al.; Schünemann et al.). Red onions, blueberries, red grapes, raspberries, and various other types of berries also contain a high concentration of quercetin; for detailed information on specific fruits and vegetables, see the USDA Flavonoid Database. Researchers speculate that the benefits of fruit and vegetables result from the antioxidant action they have on the lung (Fomieu; Strachan et al.).
3) Don’t smoke
Most people are aware of this, but it is good to see it documented. Besides causing lung cancer, of course, smoking is bad for your breathing; smoking negatively affects nearly every measurable aspect of lung function, including FVC (forced vital capacity) (Twisk et al.; Yang), FEV1 (forced expiratory volume in one second) (Twisk et al.; Yang; Beck, Doyle, and Schachter), and MEF 50% (maximal expiratory flow at 50% of vital capacity) (Beck, Doyle, and Schachter). This applies not only for tobacco, but for cannabis as well (Taylor et al.). The effects of smoking are cumulative, as measured by duration and pack years, although they are at least partially reversible upon cessation (Beck, Doyle, and Schachter; Dockery et al.).
4) Stay physically fit
Studies of the pulmonary effects of highly aerobic activities such as swimming and running have shown that there is marked improvement in both lung capacity and lung function, including vital capacity, inspiratory muscle strength, maximum expiratory pressure, maximal voluntary ventilation, and maximum sustainable ventilatory capacity (Clanton et al.; Robinson and Kjeldgaard). It should be noted that, at least in some cases, the direct effects of other types of exercise on lung function are somewhat controversial in the medical field (Womack et al.); researchers are simply not sure how some other activities affect breathing measurements. However, it is widely agreed that weight loss and increase in body muscle (indirect results of exercise) have a direct correlation with lung function, as shown by multiple studies. Weight loss positively correlates with VC (vital capacity), FVC (forced vital capacity), TLC (total lung capacity), FEV (forced expiratory volume), FEV1 (forced expiratory volume in one second), and virtually every other traditional measurement of lung function (Womack et al.; De Lorenzo et al.; Zerah et al.).
General muscle strength has been found to have a positive correlation with lung function (Hall et al.; Lazarus et al.; Ringqvist; Schoenberg, Beck, and Bouhuys; Bande et al.; Madama 153). Studies of localized, targeted muscle strengthening have been conducted, with mixed results. For example, healthy subjects in a recent study who performed sit-ups and biceps curls three to four days a week for 16 weeks significantly increased diaphragm thickness, maximal transdiaphragmatic pressure, maximaum inspiratory pressure, and maximum expiratory pressure (DePalo et al.). Another study measured different aspects of lung function, including FVC (forced vital capacity) and FEV1 (forced expiratory volume in one second), in 16 healthy subjects who participated in a 12-session training program designed to increase abdominal strength. Although abdominal muscle strength was shown to improve, there was no improvement in either FVC or FEV1 (Simpson).
Obesity has dramatic negative effects on lung capacity and function. Although some musicians have the idea that being overweight improves lung capacity or lung function, this is clearly a misconception in several measurable ways. First, there is a clear negative correlation with the spirometric measurements that are linked positively with weight loss (above), including both lung function and lung capacity. In addition, obesity leads to greater respiratory resistance, requiring greater energy to perform even the most basic respiratory tasks; specifically, obesity causes “mechanical impairment” through mass loading of the respiratory system (Zerah et al.) as well as “congestion of bronchial vessels in the airway submucosa, thickening of the airway wall, and decrease in airway size (De Lorenzo).” Anecdotal evidence of musicians who claim that being overweight makes their respiratory system somehow “stronger” or better able to exhale quickly would seem to be in direct contradiction with numerous wide-ranging scientific studies that are able to measure objectively.
5) Allow full expansion
Though sometimes a foreign concept to musicians, it is a common piece of workaday knowledge among physiologists that the bellows of the human respiratory system consists of two parts: the diaphragm and the rib cage (Tobin 31; Johnson 256). Using only the diaphragm, as is sometimes advocated by musicians, eliminates approximately one third of the vital capacity (Sebel 28); other studies indicate that this loss could even be higher than a third (Bergofsky). There are clearly many cases in which musicians require a full vital capacity breath, not just two thirds of their vital capacity. Also, since maximum expiratory flow is possible only near total lung capacity and decreases progressively as lung volume decreases, the matter of full expansion obviously affects lung function as well as lung volume (Johnson 263). Movement of the rib cage portion of the bellows occurs mechanically through what physiologists often call the “bucket handle” motion of the rib cage, wherein the rib cage (a series of bucket handles connected at the spine and sternum) moves upward and outward upon inhalation, downward and inward on exhalation. If the rib cage remains fixed (whether in an upward position, downward position, or anywhere along its range of motion), its mechanical purpose is obviously thwarted. That is to say, the rib cage must move up and down, in and out, in order to work as a bellows (Johnson 263). At no point, whether through training, concentration, or superhuman effort, can a person cause the diaphragm (not to mention the lung itself, which is passive and completely without muscle) to simply take over the rib cage’s portion of mechanical movement, whether during inhalation or exhalation.
If rib cage motion is inhibited and only the diaphragm is used during inhalation, the efficiency of the entire respiratory system is compromised. Respiratory physiologists have shown that the respiratory system works best as a whole, not through isolation of individual muscles like the diaphragm (hence the term respiratory system). Studies demonstrate, for example, that respiratory muscles other than the diaphragm do not simply offer mechanical assistance to the diaphragm. Rather, these muscles actually work together and “coordinate so as to optimize diaphragmatic function” (Goldman and Mead) (emphasis added), with “substantial coupling” between the muscles of the rib cage and the diaphragm (Boynton et al.). In other words, the diaphragm does not work as efficiently by itself as it does in combination with the other respiratory muscles. Again, it is a respiratory system, a system that uses many muscles and interlocking movements.
Finally, there is no physiological evidence that rib cage motion causes tension or restriction in any way, contrary to what musicians occasionally claim. In point of fact, motion more often relieves tension than causes tension. Think of the last time your neck was stiff—did you relieve the tension by keeping it as fixed as possible? If your arms are tense do you relax them by holding them as still as possible? If your torso feels tense, relax and let things move!
In my clinics and workshops at more than 20 universities and conservatories around the nation, this has probably been the most common problem among the hundreds of musicians whose vital capacity I have measured: they are afraid to relax and let everything move when they inhale (possibly because they are afraid they might do something wrong). When they do finally relax, take a big breath, and allow everything to expand and do its job naturally without trying to isolate muscles or execute involuntary actions, their vital capacity measurements invariably improve.
6) Don’t wear tight clothes
Breathing, of course, involves measurable work by the respiratory muscles. A major portion of this breathing work is done against the physical resistance of the abdomen and rib cage; i.e., anything keeping the abdomen and rib cage from moving freely (Davies et al 650). Clothing that restricts movement of either the abdomen or the rib cage increases resistance, creating what physiologists call external loading of the system. Restrictive clothing can significantly inhibit breathing, including decreasing vital capacity, FEV1, and forced vital capacity (DiMarco et al.; Bygrave et al.). Among the clinical practice guidelines recommended by the American Association of Respiratory Care for taking breathing measurements is the following: “Breathing movements should not be restricted by clothing” (AARP Guidelines). Specifically, experts recommend loosening anything that is tight across the abdomen, chest, or neck, including such common concert wear as neckties, belts, and tight-fitting jackets, before taking breathing measurements (Wanger 25). By way of comparison, studies have actually found that tight clothing around the abdominal wall actually compromises the respiratory system in a way similar to obesity and pregnancy, by “impeding the effectiveness of the diaphragm” to displace the abdominal viscera (Rhoades and Tanner 312). Although this general point might seem self-evident, a surprising number of musicians, particularly in performance situations, wear clothing that clearly restricts outward movement of the abdomen or chest. In another study with possible applications, subjects’ vital capacity and several other breathing measurements were recorded, then measured after subjects added a 15 kg backpack with loose shoulder and chest straps, then measured after tightening the shoulder and chest straps. The breathing measurements got progressively lower as the packs were added and straps were tightened, presumably because of the restriction of movement caused by the tightness of the straps and weight of the load (Bygrave et al.).
7) Avoid eating a lot before performing
Musicians should get ready for a performance in whatever way helps them most. However, studies have found that the presence of a large amount of undigested food in the abdomen makes displacement of abdominal contents by the diaphragm mechanically more difficult. The American Association for Respiratory Care recommends the following in its clinical guidelines for taking breathing measurements: “The patient should not have had a large meal shortly before testing” (AARP Guidelines). In other words, if you have been having problems getting big enough breaths in performances, you might want to reconsider that huge pasta dinner right before the concert.
Tension in either the abdominal muscles or the expiratory muscles of the rib cage (intercostals) during inhalation limits the respiratory system’s ability to expand and contract, thus decreasing lung efficiency and lung volume (Murray 106; Goldman and Mead). Both general tension (e.g., overall tension resulting from performance anxiety or poor practice habits) and local tension (e.g., tension resulting from attempts to hold individual parts of the respiratory system in a fixed position) are clearly counterproductive to ventilation. In addition, suprisingly, studies of professional wind instrumentalists and vocalists have shown that, although performance results are very similar, specific breathing patterns among successful professionals are remarkaby varied (Cossette, Sliwinski, and Macklem; Nelson 40; Thomasson and Sundberg; Watson et al.). Research has shown that the specifics of breathing, including the ratio of diaphragm to rib cage use, sequence of muscle recruitment, and the visual external manifestations of breathing, vary significantly according to individual build and body type (Hoit and Hixon; Wade). In other words, our bodies naturally do what is most efficient for their given build. Studies have also demonstrated that, regardless of claims sometimes made to the contrary, professional musicians have very little control over the individual muscles of the respiratory system, particularly the diaphragm (Wade), as well as a very inaccurate physiological awareness of what is actually occurring when they breathe (Watson and Hixon; Wade). Research would seem to indicate that it is more efficient for musicians to simply relax and allow natural forces to take place according to each person’s unique build and body type, rather than exerting unnecessary mental and physical energy trying to change what is largely an involuntary process. Finally, the benefits of yoga on lung function (see studies listed under “Practice deep breaths,” above) are presumably at least partially related to relaxation.
9) Maintain good posture
For various physiological reasons, lung capacity decreases by about 2 percent from standing to sitting, then about 15 percent from sitting to supine (lying on your back) (Campbell and Davis 20). “Semi-supine” posture (reclining or slouching) has been found to be significantly less efficient than sitting (Koulouris et al.). Lung function is also best when standing; both FVC and FEV1 are “slightly but significantly higher” when standing than when sitting (Townsend). This difference in posture is important enough that the American Thoracic Society recommends documenting exactly what posture is used during all breathing measurements (American Thoracic Society “Standardization of Spirometry”). In short, it makes sense to stand if you can while performing; if you cannot stand, sit up straight.
10) Take big breaths, even when you don’t think you need them
Studies suggest that there are several benefits to taking full breaths, even when it would appear from musical context that a full breath may not be necessary. (The one notable exception, which will be discussed later, is in soft dynamics.) When shallow breaths are taken, musicians have to use significantly more force (i.e., muscle) during expiration, even if only a small amount of air is actually necessary musically. Arend Bouhuys, a respiratory physiologist from Yale University who studied musicians extensively, notes, “Lower lung volumes require increasing net expiratory force to maintain the tone in wind instruments” (Bouhuys 271). Playing or singing with low lung volumes creates a situation where a person is actually working against the respiratory system’s natural elastic recoil. One physiologist puts it simply: “Recoil forces assist expiratory airflow at high lung volumes and actually oppose it at low volumes” (Sears and Davis). On the other hand, by taking full breaths, performers are able to take advantage of the natural elastic recoil of the respiratory system, use less muscle, and remain more relaxed than when using lower lung volumes. Specifically, studies have found that expiration at high lung volumes (that is, blowing out after taking a large breath) requires less force (Bouhuys 271) and fewer overall muscles than at lower lung volumes (De Troyer and Estenne). This benefit of elastic recoil in expiration decreases in an apporximately linear manner with lung volume (Murray 108). In other words, the less air you have in your lungs, the more effort it requires to expel a given amount of air. Furthermore, research has found that the airways remain more open, with less resistance, at higher lung volumes: “The airways are wider and longer at full inspiration than toward the end of expiration” (Wanger 5; Bouhuys 271). That is, a musician can exert less effort, maintain more open airways, and generally remain more relaxed after a large breath.Finally, potential rate of airflow changes according to how full the lungs are: “Maximum expiratory flow occurs only near TLC [total lung capacity] and it decreases progressively with lung volume” (Johnson 263). Thus, if rapid airflow is required (even if only for a very short burst), a large breath is better. One possible scenario in which this might apply would be on a note (or figure) that is relatively brief, but very loud, requiring very rapid flow. In order to get true maximum expiratory airflow, a full breath is required, even though the brevity of the note (or figure) would not require that all of the air inhaled actually be used.
Of course, this practice could presumably be overdone in certain situations. For example, for a soft note in a moderate pitch register, a vital capacity inhalation could actually cause a performer significant discomfort and unnecessary effort to counteract the natural recoil of the respiratory system because the natural flow would be excessive, leading to the “bottled up” phenomenon that musicians sometimes feel during soft dynamics. However, the general idea of full inhalation leading to a more efficient and relaxed exhalation would presumably be useful in most other musical situations.
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