That is a much narrower claim than the one often made in breathwork marketing. The trial tested a defined practice over a defined period; it did not establish that five minutes is the minimum effective dose, nor that every breathing method produces the same result.
The study, led by Balban and colleagues and published in Cell Reports Medicine in January 2023, compared three breathwork protocols with a mindfulness meditation control. Cyclic sighing produced the clearest pattern of improvement among the tested breathing approaches, including a greater improvement in positive mood and a greater reduction in resting respiratory rate than the mindfulness meditation group on the reported measures.
The result is useful precisely because the protocol was limited. It gives us something more concrete than the usual instruction to breathe deeply and relax. But it does not prove that a single breathwork session permanently changes the nervous system, or that one named technique is superior to every other method. The acute experience and the longer adaptation are separate questions.
The Autonomic Shift: How Breathing Changes Your Physiology
Every breathwork session works through the autonomic nervous system, or ANS: the network that helps regulate heart rate, blood pressure, breathing, digestion, and the body's response to threat. Its sympathetic branch supports mobilization and alertness. Its parasympathetic branch supports rest, digestion, and recovery. In real life, these systems do not operate as a simple on-off switch. They continuously adjust to posture, movement, temperature, thoughts, emotions, and the demands of the environment.
Breathing is unusual because it belongs to both worlds. It continues automatically while you sleep, yet you can also change its pace, depth, and rhythm deliberately. That makes respiration a practical access point to autonomic regulation. A breathwork session does not reach into the nervous system through intention alone. It changes a stream of sensory information arriving from the lungs, airways, chest wall, and blood-gas system.
The important variables are not just the number of breaths. They include:
- Respiratory rate: how many complete cycles occur in a minute.
- Tidal volume: how much air moves with each breath.
- The inhale-to-exhale relationship: whether the exhalation is shorter, equal to, or longer than the inhalation.
- Breath retention: whether breathing pauses after an inhale or exhale.
- Effort: whether the pattern is quiet and sustainable or forceful enough to provoke discomfort.
A slower rhythm and a relatively longer exhalation can influence heart-rate variability and respiratory sinus arrhythmia, the natural pattern in which heart rate tends to rise during inhalation and fall during exhalation. These effects are linked to the interaction between breathing, the vagus nerve, the brainstem, and cardiovascular reflexes. They are not evidence that the body has entered a permanently improved state. They are evidence that breathing can alter the body's regulation in the moment.
The distinction matters. A person may feel calmer after a breathwork session because the respiratory rhythm has changed, attention has narrowed, muscular effort has decreased, or the context has signaled safety. Those are meaningful effects, but they should not automatically be labeled as a lasting increase in resilience or a complete reset of the stress system.
Breathwork gives you voluntary access to an otherwise automatic system. That access is powerful, but it is not the same thing as permanent rewiring.
The nervous system also responds to the way a technique is performed. Quiet nasal breathing at a comfortable volume is a different physiological input from repeated maximal inhalations, long breath holds, or rapid overbreathing. Two practices can both be called breathwork while creating very different sensations and blood-gas changes.
That is why the phrase breathwork session is too broad to predict an outcome on its own. The protocol, intensity, duration, setting, and the person's baseline health all shape the response.
The Mechanics of Vagal Tone and Cardiac Coherence
“Vagal tone” is often used as shorthand for the body's capacity to regulate itself, but it is not a single feeling and it is not measured simply by noticing whether you feel relaxed. Researchers commonly examine heart-rate variability, or HRV, as one window into autonomic regulation. HRV describes variation in the timing between heartbeats. It is influenced by breathing, posture, physical fitness, sleep, medication, illness, age, and measurement conditions.
That last point is easy to lose in consumer wellness language. A higher HRV reading on a wearable does not automatically mean that a person has become more emotionally regulated. Nor does a lower reading prove that a breathwork practice has failed. HRV is context-sensitive. It is most useful when trends are interpreted cautiously and measured under reasonably similar conditions.
Slow breathing can increase the visible coordination between respiration and heart rate. During inhalation, heart rate commonly accelerates slightly; during exhalation, it commonly slows. This pattern is known as respiratory sinus arrhythmia. At certain breathing rates, the effect can become more pronounced because respiratory movement, heart-rate variation, and blood-pressure reflexes interact more strongly.
The term cardiac coherence is frequently used for this kind of coordination. It describes a pattern of cardiovascular oscillation rather than a mystical state or a guaranteed therapeutic endpoint. Many coherent-breathing protocols use a slow, regular rhythm, often near five or six breaths per minute, with an approximately even inhale and exhale. That can be a useful structure, but it is not a universal prescription. For some people, deliberately slowing to that pace feels steady. For others, it creates air hunger, tension, or an urge to overbreathe.
A simplified comparison helps clarify what different patterns are trying to do:
| Parameter | What it changes | What may be observed |
|---|---|---|
| Slower breathing | Gives each respiratory cycle more time and may increase respiratory-cardiovascular coordination | A more noticeable rise and fall in heart rate across the breath |
| Longer exhalation | Extends the phase commonly associated with a slowing of heart rate | A subjective sense of settling, provided the pattern remains comfortable |
| Breath retention | Introduces a pause and changes the timing of the respiratory cycle | Air hunger or pressure in some people, especially when the pause is prolonged |
| Larger breaths | Moves more air than ordinary quiet breathing | Tingling, lightheadedness, or discomfort if the pattern becomes excessive |
| Regular pacing | Reduces irregularity and gives attention a stable object | Greater awareness of the body and a clearer sense of rhythm |
The 4-7-8 method illustrates why a named technique should be understood as a structure, not a promise. It uses a four-second inhale, a seven-second hold, and an eight-second exhale. The long exhalation may feel calming for some practitioners, while the breath hold may feel activating or uncomfortable for others. There is no reason to force the prescribed count if the result is straining, gasping, or escalating anxiety.
Coherent breathing uses a different arrangement: a slower, more symmetrical rhythm without the same emphasis on retention. Box breathing divides the cycle into four equal parts, usually including pauses after the inhale and exhale. Cyclic sighing uses two inhalations followed by a prolonged exhalation. These methods overlap in their attention to pace and respiratory control, but their immediate physiological demands are not identical.
None of them requires an elaborate setting. A timer can be enough. A guided recording may help with pacing, but it does not turn a breathing exercise into a medically supervised intervention. The useful question is not whether a room looks calming. It is whether the rhythm can be maintained without excessive effort, dizziness, panic, or an urge to compensate with larger breaths.
Cyclic Sighing and the 28-Day Protocol for Mood Regulation
Cyclic sighing was the most prominent protocol in the Stanford trial. Its basic pattern is simple:
1. Take a deep inhale through the nose. The breath is fuller than an ordinary resting breath, but it does not need to be maximal.
2. Add a shorter second inhale. This brief “top-off” breath follows the first inhalation.
3. Exhale slowly and for longer. The exhalation is unhurried and extended, usually through the mouth.
The second inhalation is intended to expand the lungs further before the long exhalation. In practice, the central feature is the contrast between the two-part inhale and the prolonged release of air. The technique should not become a contest to fill the lungs completely or to extend the exhale until discomfort.
In the Stanford study, participants practiced for five minutes per day over 28 days, using a guided protocol at home. The comparison group practiced mindfulness meditation for the same daily period. The study therefore examined a particular dose and schedule. It did not establish five minutes as the minimum amount required for an effect, and it did not show that practicing for longer would necessarily produce a larger benefit.
At the 28-day endpoint, the findings included:
- The cyclic-sighing group showed a statistically significant improvement in positive mood compared with the mindfulness meditation group on the reported measure.
- Resting respiratory rate decreased more in the cyclic-sighing group than in the mindfulness meditation group.
- The breathwork protocols as a group were associated with reductions in physiological arousal markers, with the exhale-focused cyclic-sighing condition showing the most consistent pattern among the tested approaches.
The wording matters. There were three breathwork protocols in the trial, not two. And the study was not designed to prove that cyclic sighing defeats every other breathing method. It compared the tested breathwork conditions with a mindfulness meditation control, while the differences between the three breathwork protocols should not be inflated into a universal ranking.
Nor does the study show that the protocol changes a person's underlying personality, permanently raises HRV, or creates a trait-level transformation. It shows that a defined daily practice was associated with measurable differences at the end of a 28-day study period. That is a meaningful result without turning it into a claim the data cannot carry.
The useful promise of cyclic sighing is modest and concrete: a short, repeatable practice was associated with mood and respiratory-rate changes after 28 days in a controlled trial.
For someone trying the method, the practical version is deliberately unglamorous. Sit or lie down somewhere safe. Follow the two-part inhale and the longer exhale for a comfortable period. Stop or return to ordinary breathing if lightheadedness, tingling, chest discomfort, or panic develops. The research protocol can guide expectations, but it should not become a reason to ignore the body's warning signals.
Consistency is also worth describing accurately. Repeating a practice gives researchers a way to study cumulative effects, but a missed day does not literally reset an adaptation clock. The nervous system is not a machine that returns to zero after one interruption. A disrupted routine may make the habit harder to maintain, and fewer practice sessions mean less exposure to the protocol, but the available study does not justify an absolute rule about missed days.
The same caution applies to timelines. The supplied evidence supports a comparison at the end of 28 days. It does not establish that mood changes must appear in the first two weeks, that physiological changes begin only in week four, or that HRV follows a particular schedule. People may notice a subjective shift during the first session, or they may notice nothing immediate. Neither experience confirms or disproves the longer-term findings.
Comparing Techniques: From 4-7-8 Rhythms to Slow Breathing
The breathwork landscape is crowded with branded methods. Most of them manipulate a limited set of variables: pace, depth, pauses, and the relative length of the exhalation. The names can make the techniques sound more different than they are, but the experience can still vary considerably depending on how forcefully the person breathes.
| Technique | Basic structure | Main feature | What the evidence allows you to say |
|---|---|---|---|
| Cyclic sighing | Two-part inhale followed by a prolonged exhale | Emphasizes a long exhalation after the second inhale | Tested in the 2023 Stanford randomized trial; associated with mood and resting respiratory-rate changes at 28 days |
| Coherent breathing | Slow, regular inhale and exhale, often close to equal length | Encourages respiratory-cardiovascular coordination | Has a mechanistic rationale and support from HRV research, but should not be treated as identical to the Stanford protocol |
| 4-7-8 breathing | Four-second inhale, seven-second hold, eight-second exhale | Combines a long exhale with a substantial pause | Widely used, but evidence for the named protocol is more limited than broad evidence on slow breathing |
| Box breathing | Inhale, hold, exhale, hold for equal counts | Uses symmetry and predictable pacing | May help structure attention and arousal; adoption in tactical settings is not the same as strong clinical trial evidence |
| Slow diaphragmatic breathing | Comfortable slow inhale and exhale without a required hold | Reduces pace while minimizing complexity | Supported by a broader body of breathing and autonomic research, though effects depend on the exact protocol |
The strongest distinction is between a technique that has been tested in a particular randomized trial and a technique that is widely recommended because it is plausible, familiar, or easy to teach. Cyclic sighing has a specific controlled-trial result. Coherent breathing has a substantial mechanistic and HRV literature. The 4-7-8 and box-breathing labels are recognizable, but their popularity should not be confused with proof that they produce the same outcomes under the same conditions.
A reasonable choice depends on what the person can perform without strain:
- Choose cyclic sighing when a two-part inhale and longer exhale feel manageable and you want to follow the protocol that has the clearest result in the 28-day trial.
- Choose a slower, even rhythm when breath holds make you tense or air-hungry.
- Choose 4-7-8 only if the retention phase remains comfortable; the count is not a test of discipline.
- Choose box breathing when predictable symmetry helps focus, particularly during a brief period of situational stress.
- Choose ordinary slow diaphragmatic breathing when simplicity matters more than a branded sequence.
A technique practiced regularly is easier to evaluate than one attempted once under ideal conditions. But regular practice should not be turned into a moral test. The study examined a 28-day schedule; it did not prove that missing a session erases prior progress or that longer practice is always better. The right interpretation is narrower: repeated exposure may matter, and the available trial measured outcomes after four weeks.
Nor should a single session be expected to produce trait-level change. A person can experience an acute state shift — less muscular tension, a slower subjective tempo, or a change in attention — without that shift becoming a durable alteration in stress reactivity. Long-term adaptation is a research question involving repeated practice, measurement conditions, and individual differences. It cannot be inferred from the feeling produced by one compelling session.
Navigating the Somatic Experience and Emotional Release
A somatic breathwork experience can be vivid even when the technique is physically simple. Tingling in the hands or around the mouth, lightheadedness, warmth, chills, muscle tightening, chest sensations, and changes in body awareness are commonly reported during more deliberate or intense breathing. These sensations should be interpreted carefully rather than automatically described as evidence of healing, trauma release, or a deep nervous-system reset.
Overbreathing can lower carbon dioxide in the blood and contribute to respiratory alkalosis. That shift may produce tingling, dizziness, visual changes, or muscle sensations. It can happen when a person breathes too quickly, too deeply, or too forcefully for the body's immediate needs. A prolonged exhalation is not automatically dangerous, but any protocol that leads to repeated air hunger or compensatory gasping is being performed at an intensity that may be counterproductive.
The first response to uncomfortable symptoms is not to push through them. Return to a quiet, ordinary breathing pattern. Reduce the depth of the inhale, shorten the exhale, remove the breath hold, or stop the exercise altogether. Sit or lie down, particularly if balance is affected. If symptoms are severe, persistent, or unlike the sensations normally associated with the exercise, seek medical advice rather than assigning them a wellness explanation.
Emotional responses are more difficult to classify. A person may feel sadness, anger, relief, fear, calm, or unexpected laughter during or after a session. Changing attention toward internal sensations can make emotions more noticeable. A shift in arousal may also alter how thoughts and memories are experienced. But the feeling of an emotional release does not, by itself, identify its cause or prove that a stored memory has been processed.
The language of “releasing trauma through the breath” can be especially misleading when it is presented as a physiological certainty. Breathwork may become part of a broader therapeutic process, but a breathing pattern is not a substitute for trauma-informed psychotherapy, medical care, or crisis support. Strong emotion is not always a sign that the technique is working. Sometimes it is a sign that the pace is too intense or that the setting does not provide enough support.
A safer way to approach the emotional side of a session is to keep interpretation slower than sensation:
1. Name the experience without turning it into a diagnosis. Tingling can be tingling. Sadness can be sadness. Neither needs an immediate story about what it means.
2. Lower the intensity before searching for insight. If the body is dizzy, tense, or panicked, return to ordinary breathing first.
3. Notice the context. Sleep loss, caffeine, recent conflict, medication, illness, and an unfamiliar group setting can all influence the experience.
4. Reflect after the session. A brief note about mood, bodily sensations, and what changed can be more useful than making a major interpretation while breathing is still altered.
5. Use professional support when the response is overwhelming. A qualified clinician is better placed to help with recurring panic, trauma symptoms, dissociation, or persistent distress.
During a breathwork session, safety is also practical rather than ceremonial. Do not practice in water, while driving, on a height, or during an activity that requires uninterrupted balance and alertness. People with relevant cardiovascular, respiratory, neurological, or psychiatric conditions should discuss more intense protocols with a qualified healthcare professional. Pregnancy, recent surgery, unexplained fainting, and medications that affect breathing or cardiovascular function are also reasons to avoid treating a vigorous online session as a one-size-fits-all exercise.
The most defensible expectation is therefore modest. A breathwork session may change breathing, attention, and autonomic state in the short term. A repeated protocol may be associated with broader changes over the period studied. The exact response depends on the method and the person, and discomfort is not a measurement of therapeutic depth.
What the 28-Day Finding Actually Changes
The Stanford trial gives breathwork a useful place in the conversation about stress regulation, but not an excuse to exaggerate. It tested three breathing protocols and a mindfulness meditation control over 28 days. Cyclic sighing showed the clearest reported advantages on positive mood and resting respiratory rate, while the breathwork conditions were associated with reductions in physiological arousal markers. Those findings support further study and give readers a reproducible protocol to consider.
They do not establish a universal minimum dose. They do not show that skipping a day resets adaptation. They do not provide a timetable for when subjective or physiological effects must appear. They do not demonstrate a specific HRV outcome, a fixed reduction in breaths per minute, or a permanent change in the nervous system. And they do not crown cyclic sighing the winner of every possible comparison.
That precision is not a weakness. It is what makes the practice easier to use responsibly. Start with a defined rhythm, a comfortable intensity, and a clear observation period. Track what actually changes: sleep, perceived stress, mood, breath comfort, or the ability to settle after a demanding moment. Treat those observations as personal information, not as proof that a biological mechanism has been confirmed.
Breathwork is most useful when it remains both embodied and proportionate. The breath can influence the nervous system because it is connected to the nervous system. It can help shift a state without single-handedly resolving every condition that state contains. A five-minute practice may be worth repeating. It is not a promise that five minutes can repair everything.
