As newborns, we enter the world by inhaling. In leaving, we exhale. (In fact, in many languages the word “exhale” is synonymous with “dying.”) Breathing is so central to life that it is no wonder humankind long ago noted its value not only to survival but to the functioning of the body and mind and began controlling it to improve well-being.

As early as the first millennium B.C., both the Tao religion of China and Hinduism placed importance on a “vital principle” that flows through the body, a kind of energy or internal breath, and viewed respiration as one of its manifestations. The Chinese call this energy qi, and Hindus call it prana (one of the key concepts of yoga).

A little later, in the West, the Greek term pneuma and the Hebrew term rûah referred both to the breath and to the divine presence. In Latin languages, spiritus is at the root of both “spirit” and “respiration.”

Recommendations for how to modulate breathing and influence health and mind appeared centuries ago as well. Pranayama (“breath retention”) yoga was the first doctrine to build a theory around respiratory control, holding that controlled breathing was a way to increase longevity.

In more modern times, German psychiatrist Johannes Heinrich Schultz developed “autogenic training” in the 1920s as a method of relaxation. The approach is based partly on slow and deep breathing and is probably still the best-known breathing technique for relaxation in the West today. The contemporary forms of mindfulness meditation also emphasize breathing-based exercises.

In fact, every relaxation, calming or meditation technique relies on breathing, which may be the lowest common denominator in all the approaches to calming the body and mind. Research into basic physiology and into the effects of applying breath-control methods lends credence to the value of monitoring and regulating our inhalations and exhalations.

Yoga and meditation have inspired many of the breathing exercises used today. The benefits of controlled respiration were first theoretically posited centuries ago by the practitioners of pranayama yoga. Credit: Getty Images

Mind under the Influence

Even a rudimentary understanding of physiology helps to explain why controlled breathing can induce relaxation. Everyone knows that emotions affect the body. When you are happy, for instance, the corners of your mouth turn up automatically, and the edges of your eyes crinkle in a characteristic expression. Similarly, when you are feeling calm and safe, at rest, or engaged in a pleasant social exchange, your breathing slows and deepens. You are under the influence of the parasympathetic nervous system, which produces a relaxing effect. Conversely, when you are feeling frightened, in pain, or tense and uncomfortable, your breathing speeds up and becomes shallower. The sympathetic nervous system, which is responsible for the body’s various reactions to stress, is now activated. Less well known is that the effects also occur in the opposite direction: the state of the body affects emotions. Studies show that when your face smiles, your brain reacts in kind—you experience more pleasant emotions. Breathing, in particular, has a special power over the mind.

This power is evident in patients who have breathing difficulties. When these difficulties are sporadic and acute, they can trigger panic attacks; when they are chronic, they often induce a more muted anxiety. It is estimated that more than 60 percent of people with chronic obstructive pulmonary disease (COPD) have anxiety or depressive disorders. These disorders probably stem in part from concerns about the consequences of the disease (what could be more distressing than struggling to breathe?), but purely mechanical factors may contribute as well: the difficulty these patients experience often leads to faster breathing, which does not necessarily improve the quality of their oxygen supply but can aggravate their physical discomfort and anxiety.

Rapid breathing can contribute to and exacerbates panic attacks through a vicious circle: fear triggers faster breathing, which increases fear. In 2005 Georg Alpers, now at the University of Mannheim in Germany, and his colleagues observed significant and unconscious hyperventilation when people who had a driving phobia took their vehicles on the highway (where they might not be able to pull over if they become agitated).

Whether anxiety derives from breathing problems or other causes, it can be eased by a number of breathing techniques derived from traditional Eastern approaches (see “Six Techniques for Relieving Stress”). For example, “follow your breath,” an exercise that focuses attention on breathing, is one of the first steps in mindfulness meditation, whereas alternate nostril breathing comes from yoga. Combining reassuring thoughts with breathing is an approach incorporated into sophrology, a technique that emphasizes harmony of body and mind and that borrows exercises from many approaches, including yoga and mindfulness.

Overall, research shows that these techniques reduce anxiety, although the anxiety does not disappear completely. Breathing better is a tool, not a panacea. Some methods have been validated by clinical studies; others have not. But all of those I describe in this article apply principles that have been proved effective. They aim to slow, deepen or facilitate breathing, and they use breathing as a focal point or a metronome to distract attention from negative thoughts.

Spotlight on Cardiac Coherence

A close look at one popular technique—cardiac coherence—offers more detail about the ways that breathing exercises promote relaxation. With the help of biofeedback, the approach attempts to coordinate breathing with heart rate, slowing and steadying breathing to slow and stabilize the heartbeat.

The method was developed based on the understanding that slow, deep breathing increases the activity of the vagus nerve, a part of parasympathetic nervous system; the vagus nerve controls and also measures the activity of many internal organs. When the vagus nerve is stimulated, calmness pervades the body: the heart rate slows and becomes regular; blood pressure decreases; muscles relax. When the vagus nerve informs the brain of these changes, it, too, relaxes, increasing feelings of peacefulness. Thus, the technique works through both neurobiological and psychological mechanisms.

Cardiac coherence’s stabilization of the heartbeat can dampen anxiety powerfully. Conversely, patients with overactive heartbeats are sometimes misdiagnosed as victims of panic attacks because their racing heartbeat affects their mind.

A typical cardiac coherence exercise involves inhaling for five seconds, then exhaling for the same amount of time (for a 10-second respiratory cycle). Biofeedback devices make it possible to observe on a screen how this deep, regular breathing slows and stabilizes the beats. (The space between two heartbeats on the display is never exactly the same, but it becomes increasingly more consistent with this technique.) Several studies have confirmed the anxiety-diminishing effect of these devices, although the equipment probably has more influence on the motivation to do the exercises (“It makes it seem serious, real”) than on the physiological mechanisms themselves. Simply applying slow breathing with the same conviction and rigor could well give the same result.

Some versions of cardiac coherence recommend spending more time on exhaling than on inhaling (for example, six and four seconds). Indeed, your heart rate increases slightly when you inhale and decreases when you exhale: drawing out the second phase probably exerts a quieting effect on the heart and, by extension, on the brain. This possibility remains to be confirmed by clinical studies, however.

Other work suggests that the emotional impact of the breathing done in cardiac coherence and various other kinds of exercises stems not only from effects on the periphery—on the parasympathetic nervous system—but also from effects on the central nervous system. Breathing may well act directly on the brain itself.

In 2017, for instance, Mark Krasnow of Stanford University and his colleagues showed in mice that a group of neurons that regulates respiratory rhythms (the pre-Bötzinger complex in the brain stem) controls some of the activity of the locus coeruleus, a region involved in attention, wakefulness and anxiety. Breathing techniques may influence this seat of emotions by modulating the activity of the pre-Bötzinger complex.

Beyond any direct effects produced by slowed breathing, the attention given to inhaling and exhaling may play a role in the brain’s response. In 2016 Anselm Doll and his colleagues, all then at the Technical University of Munich, showed that this attentional focus eases stress and negative emotions, in particular by activating the dorsomedial prefrontal cortex, a regulatory area of the brain, and by reducing activity in the amygdala, which is involved in these emotions.

In addition, paying attention to breathing causes most people to slow it down and to deepen it, which as I have mentioned, is soothing. Cognitive resources are limited, and so when individuals concentrate on breathing, they are not thinking about their worries. Those who practice mindfulness learn to notice when their attention drifts away from breathing and goes back to their concerns, and they train themselves to return periodically to their breathing. This refocusing has a relaxing effect on anyone and helps to combat ruminative thinking in people who have anxiety or depression, especially those who are particularly prone to negative thoughts that run in a loop.

When to Use Breathing Techniques

What is the best time to apply slow-breathing techniques? One is during occasional episodes of stress—for example, before taking an exam, competing in a sporting event or even attending a routine meeting at work. In 2017 Ashwin Kamath of Manipal University in India and his colleagues studied stage fright before a public speaking engagement. The participants, all medical students, spent 15 minutes doing alternate nostril breathing—that is, slowly inhaling through one nostril and exhaling through the other by applying finger pressure to the side of the nose not being used. Compared with members of the control group, participants experienced somewhat less stress when speaking publicly.

These exercises may also help when insomnia strikes. In 2012 Suzanne M. Bertisch of Harvard Medical School and her colleagues reported, based on survey data, that more than 20 percent of American insomniacs do these breathing exercises to sleep better. They may be on to something. In 2015 Cheryl Yang and her team at National Yang-Ming University in Taiwan showed that 20 minutes of slow breathing exercises (six respiration cycles per minute) before going to bed significantly improves sleep. Insomniac participants went to sleep faster, woke up less frequently in the night and went back to sleep faster when they did wake up. On average, it took them only 10 minutes to fall asleep, almost three times faster than normal. The investigators attributed the results both to the calming mediated by the parasympathetic system and to the relaxing effect of focused breathing.

But respiratory techniques do not work only for acute stresses or sleep problems; they can also relieve chronic anxiety. They are particularly effective in people with psychiatric disorders such as phobias, depression and post-traumatic stress disorder. In 2015 Stefania Doria and her colleagues at Fatebenefratelli e Oftalmico Hospital in Milan, Italy, offered 10 training sessions of two hours each, spread out over two weeks, to 69 patients with anxiety or depressive disorders. The training included a varied set of breathing techniques (such as abdominal breathing, acceleration and deceleration of rhythm, and alternate nostril breathing.), combined with some yoga stretches. The researchers observed a significant decrease in symptoms at the end of the protocol. Even better, improvement was maintained two and six months later, with follow-up sessions just once a week and some home practice during this period.

Breathing exercises also help to counter the accumulation of minor physical tension associated with stress. Therapists recommend doing them regularly during the day, during breaks or at moments of transition between two activities: you simply stop to adjust your posture and allow yourself a few minutes of quiet breathing. Therapists often suggest the “365 method”: at least three times a day, breathe at a rhythm of six cycles per minute (five seconds inhaling, five seconds exhaling) for five minutes. And do it every day, 365 days a year. Some studies even suggest that, in addition to providing immediate relief, regular breathing exercises can make people less vulnerable to stress, by permanently modifying brain circuits. In a practice that may seem counterintuitive, however, counselors may encourage some anxious patients to breathe rapidly instead of slowly, as part of an effort to train them to cope with their anxieties (see box “Inhale for Panic!”).

But why confine breathing techniques to negative emotions? It is also worth applying them during pleasurable moments, to take the time to appreciate and remember them. In short, one can pause and breathe for enjoyment as well as to calm down.

Open Questions

Tradition and experience encourage the use of respiratory-control techniques, and scientific studies increasingly suggest that it is a good idea. Nevertheless, further research is still needed, particularly given that some studies lack control groups. One exception stands out: focusing on breathing often is not a good idea for people having a panic attack that stems from anxiety over their physical state (also known as interoceptive anxiety). In this case, focusing on physiology, such as muscle tension or breathing, may actually amplify panic (“Now that I’m paying attention to it, my breathing doesn’t seem regular. Am I choking? What will happen if I suddenly stop breathing?”) For these people, breathing techniques should be tested and practiced under the supervision of a therapist.

Otherwise, considering how often everyone experiences emotional discomfort in their everyday life and its negative consequences on health, we would all do well to regularly pay attention to the way we breathe. Start with brief periods of conscious, quiet breathing several times a day. Breathing is like solar energy for powering relaxation: it’s a way to regulate emotions that is free, always accessible, inexhaustible and easy to use.

In fact, I am mystified that controlled breathing is not recommended and practiced more widely. Perhaps it is perceived as too simple, commonplace and obvious to be a remedy. Faced with the complexity of negotiating the ups and downs of human life, many people may assume that simple solutions cannot be effective.

Or maybe we are intimidated by the sacred aspect of breathing, by its connection to life and, especially, to death. In the 1869 novel The Man Who Laughs, Victor Hugo wrote: “Generations are puffs of breath, that pass away. Man respires, aspires, and expires.” Ultimately, we don’t like to think that we are nothing more than “puffs of breath.”

Six Techniques for Relieving Stress

Here are some commonly used breathing techniques. Five to 10 minutes of exercise can relieve sporadic stress and even fend off panic attacks. More regular practice can lower the daily levels of anxiety.

Stand Up Straight

Posture is important for breathing: hold yourself straight, without stiffness, shoulders back, sitting or standing. This body posture facilitates the free play of the respiratory muscles (of the diaphragm and between the ribs). Good posture enables your body to breathe properly on its own.

Follow Your Breath*

Simply observe your respiratory movements: be aware of each inhalation and exhalation. Focus on the sensations you feel as air passes through your nose and throat or on the movements of your chest and belly. When you feel your thoughts drift (which is natural), redirect your attention to your breath.

Abdominal Breathing

Breathe “through your stomach” as much as possible: start by inflating your belly by inhaling, as if to fill it with air, then swell your chest; as you exhale, first “empty” your stomach, then your chest. This type of breathing is easier to observe and test while lying down, with one hand on your stomach.

Rhythmic Breathing

Near the end of each inhalation, pause briefly while mentally counting “1, 2, 3” and holding the air before exhaling. This counting while not breathing can also be done after exhaling or between each inhalation or exhalation. It is often recommended for anxious patients to calm anxiety attacks because it induces a beneficial slowing of the breathing rate.

Alternate Nostrils*

Breathe in and out slowly through one nostril, holding the other one closed using your finger; then reverse and continue by alternating regularly. There are many variations of this exercise—for example, inhaling through one nostril and exhaling through the other. Research suggests that what is most important, aside from slowing the breathing rhythm, is breathing through the nose, which is somewhat more soothing than breathing through your mouth.

Think Reassuring Thoughts While Breathing

With each breath, think soothing thoughts (“I am inhaling calm”). With each exhalation, imagine that you are expelling your fears and worries (“I am exhaling stress”).

*Technique validated by clinical studies.

Inhale for Panic!

Whereas slow breathing soothes, overly rapid breathing can induce feelings of stress and anxiety. This phenomenon is used in behavioral therapy sessions to train anxious patients to confront their emotions directly. By deliberately hyperventilating, patients artificially trigger an unpleasant anxiety, which they get accustomed to feeling and learn to put in perspective. This technique also enables them to see that poor breathing habits amplify their fear.