Breathing happens without you. It is also the one part of your autonomic nervous system you can change on purpose. Slow it down, lengthen the out-breath, and the body tends to follow.
We collected the research so you don’t have to: 43 peer-reviewed studies and reviews, each checked against its original record. Below is what they found.
Every breath nudges your heart rate: up on the way in, down on the way out. Drag the slider to change the breathing pace. Near six breaths a minute, for many adults, the heart’s swing grows largest.
An illustration of the resonance model described by Lehrer & Gevirtz (2014), not real data. Your own resonance pace may sit a little either side of six.
BreathHeart rateswing ±8 bpm
Chapter 01
Slow down to about six breaths a minute.
Most of us breathe ten to twenty times a minute at rest. Slow that to around six and something measurable happens: heart rate rises a little on every in-breath and falls on every out-breath, and those waves grow larger. Researchers call this resonance, and it is one of the most consistently reported effects in breathing science.
Summarises evidence that slow breathing affects the respiratory, cardiovascular and autonomic nervous systems, including heart rate variability, baroreflex sensitivity and respiratory sinus arrhythmia. Heart rate variability is typically greatest at about 6 breaths per minute. The authors say much more research is needed.
Study details
Design. Narrative review of research on slow breathing in healthy people, with slow breathing defined as 4 to 10 breaths per minute.
Caveats. Narrative, not systematic, review. Covers healthy people only. The authors call for further research before clinical conclusions are drawn.
Heart rate oscillations are largest when people breathe at their resonance frequency, which varies between individuals but is about 0.1 Hz (six breaths per minute). The best-supported explanation is a strengthening of the baroreflex, the reflex that helps regulate blood pressure. Effects on vagal pathways to the brain are also proposed.
Study details
Design. Narrative review of the mechanisms behind heart rate variability biofeedback and breathing at resonance frequency.
Caveats. A review of mechanisms, not a trial. The authors describe some of the proposed mechanisms as speculative.
Voluntary slow breathing increased vagally mediated heart rate variability, a marker of parasympathetic nervous system activity. The increase appeared during practice, immediately after a single session, and after multi-session programmes.
Study details
Design. Systematic review and meta-analysis of 223 studies. It looked at heart rate variability during slow breathing (172 studies), immediately after a single session (16) and after multi-session programmes (49).
Caveats. Heart rate variability is a physiological marker. A change in it does not by itself show a long-term health benefit.
HRV biofeedback showed a significant small-to-moderate overall benefit, similar in size to other effective treatments. The largest effects were for anxiety, depression, anger and athletic or artistic performance. The smallest were for PTSD, sleep and quality of life.
Study details
Design. Systematic review and meta-analysis of 58 randomised controlled studies of heart rate variability biofeedback, covering a wide range of symptoms and performance outcomes.
Caveats. Only a few studies for each individual outcome. Effects were larger against inactive than active controls. Biofeedback adds a sensor and live feedback, so it is not identical to paced breathing alone.
Reciting the rosary (Ave Maria) or a yoga mantra slowed breathing to almost exactly six breaths a minute, from about 14 during spontaneous breathing. It also produced strong, synchronised increases in cardiovascular rhythms, and baroreflex sensitivity rose.
Study details
Design. Laboratory comparative study, 23 healthy adults. Breathing, heart rhythm, blood pressure and cerebral circulation were measured during spontaneous breathing, metronome-paced breathing and recitation of the rosary or a mantra.
Caveats. Small sample of healthy adults. The study measured physiological rhythms, not health outcomes.
After the breathing exercise, the resonance-frequency group reported more positive mood than both other groups and had a higher LF/HF heart rate variability ratio than controls. It also had lower systolic blood pressure than controls during the stress task and recovery.
Study details
Design. Randomised single-session experiment; 95 undergraduates breathed for 15 minutes at their individually determined resonance frequency (about 6 breaths per minute), at 1 breath per minute faster, or sat quietly, then did a stressful arithmetic task (PASAT).
Caveats. Single session in college students; the authors note it is unknown how effects develop over weeks of practice. The 1-breath-faster group did not differ significantly from either other group on blood pressure.
Across the included studies, slow breathing was linked with higher heart rate variability and changes in brain activity (more EEG alpha, less theta power). People reported more comfort, relaxation, vigour and alertness, and fewer symptoms of arousal, anxiety, depression, anger and confusion.
Study details
Design. Systematic review of 15 studies of slow breathing techniques (under 10 breaths per minute) in healthy people, selected from 2,461 abstracts.
Caveats. Small evidence base: 15 studies, with about 9 to 58 people in each slow-breathing group, and none was a randomised controlled trial (10 within-subject and 5 before-and-after designs). The studies differed too much for their results to be pooled, and the authors note a lack of standardised methods and descriptions of breathing techniques across the field.
Pooled trials suggest that breathwork is associated with modest drops in self-reported stress and anxiety. In some trials, a few minutes a day was enough for people to notice a difference. The largest single trial also reminds us that much of the benefit may come from simply stopping to breathe on purpose, at almost any slow pace.
Breathwork was associated with lower self-reported stress than control conditions, a small-to-medium effect (g = -0.35). Effects of similar size were found for self-reported anxiety and depressive symptoms.
Study details
Design. Meta-analysis of randomised controlled trials. The main stress analysis pooled 12 trials with 785 adults. Secondary analyses pooled 20 trials for anxiety and 18 for depressive symptoms.
Caveats. Most trials were at moderate risk of bias, and all outcomes were self-reported. Ten of the 12 stress trials used mainly slow-paced breathing. The authors urge caution and call for better-designed trials.
Breathing-focused interventions reduced anxiety symptoms more than control conditions, a moderate-to-large effect overall. The effect was smaller against active comparison treatments than against inactive controls, but it was still significant.
Study details
Design. Meta-analysis of 40 randomised controlled trials (3,047 participants in total) of breathing-focused interventions, such as diaphragmatic breathing, slow or paced breathing and heart rate variability biofeedback, that measured trait anxiety.
Caveats. 35 of the 40 trials were rated at high risk of bias. Results varied widely between studies. The trials mixed clinical and non-clinical samples and many types of breathing intervention.
All groups reported less anxiety and better mood after each session. Cyclic sighing (a double inhale followed by a long, slow exhale) produced a significantly greater increase in positive affect and a larger reduction in resting respiratory rate than mindfulness meditation.
Study details
Design. Remote randomised controlled trial; 108 adults practised 5 minutes a day for 28 days: cyclic sighing (n = 30), box breathing (n = 21), cyclic hyperventilation with retention (n = 33) or mindfulness meditation (n = 24). Physiology was tracked with a wrist-worn wearable.
Caveats. Small groups; remote, self-reported adherence; originally exploratory and registered retrospectively. Heart rate variability and resting heart rate did not change in any group. Box breathing improved mood within sessions but did not differ significantly from mindfulness. One author declared becoming an adviser to WHOOP, the wearable used in the study, in 2022.
After one 5-minute session, state anxiety was lower and high-frequency heart rate variability (a marker of vagal activity) was higher in both age groups. The heart rate variability increase was larger in older adults. RMSSD, another heart rate variability measure, did not change.
Study details
Design. Before-and-after study of a single session, 47 adults (25 younger, 22 older). Participants did one 5-minute, video-guided session of deep and slow breathing with a longer exhale than inhale.
Caveats. No control group: a before-and-after comparison only. Small sample. A single short session, so it shows short-term change only.
Compared with normal breathing, both box breathing and prolonged exhalation blunted the stress-related rise in heart rate, state anxiety and salivary alpha-amylase. Heart rate variability, cortisol and cognitive performance did not differ between groups.
Study details
Design. Randomised controlled trial; 66 adults (22 per group) did normal breathing, box breathing (4 s in, 4 s hold, 4 s out, 4 s hold) or prolonged exhalation (3 s nasal inhale, 6 s pursed-lip exhale, one breath every 30 s) for 5 minutes before and 1 minute during a virtual social stress test.
Caveats. Single session, modest sample, and a modified virtual stress test in which cortisol showed no stress response in any group. The prolonged-exhalation condition was one guided breath every 30 seconds, not continuous paced breathing.
Both box breathing and cyclic sighing were associated with greater reductions in state anxiety than the control condition. Both were also linked to slower reaction times on an attention test, while box breathing was linked to fewer inhibition errors.
Study details
Design. Preregistered pilot ecological momentary intervention; 47 university students, in real-life moments of acute threat, did one minute of box breathing, cyclic sighing or a passive control, with state anxiety and attention measured 5 minutes later.
Caveats. Pilot study with 47 students; the abstract does not describe how conditions were assigned. One-minute exercises and a 5-minute follow-up only. Attention results were mixed.
Stress, anxiety, depression and wellbeing improved in both groups, but coherent breathing did no better than the placebo breathing practice. The authors note that the placebo may itself have been an active practice.
Study details
Design. Randomised placebo-controlled trial, 400 UK adults from the general population. Participants did about 10 minutes a day for 4 weeks of audio-guided coherent breathing (about 5.5 breaths per minute) or a matched placebo breathing practice (12 breaths per minute).
Caveats. Practice was remote and unsupervised. The comparison group also did a guided breathing practice, so the trial tests the slower pace specifically, not breathwork against doing nothing.
Making the out-breath longer than the in-breath is one of the oldest instructions in breathwork, and many of Breathform’s calming practices use it. The evidence is genuinely mixed: some studies find extra benefit, others find the slow pace matters more than the ratio. We think it is a gentle, sensible default, not a magic trick.
People felt more relaxed, less stressed, more mindful and more positively energised with the longer-exhale ratio than with the longer-inhale ratio. The longer exhale also increased high-frequency heart rate variability, but only when breathing at 6 breaths per minute.
Study details
Design. Within-subjects laboratory experiment; 30 undergraduates recruited (23 analysed, nearly all women) breathed at 6 or 12 breaths per minute with an inhalation/exhalation ratio of either 0.42 (exhale longer) or 2.33 (inhale longer), in counterbalanced order.
Caveats. Single lab session with 23 people analysed, almost all young women. In the '6 breaths per minute' conditions people actually breathed at about 7.3 to 7.7 a minute, and a 2024 review (Meehan 2024) rated the study at high risk of bias. The comparison was longer exhale vs longer inhale, not vs equal breaths. Relaxation measures were self-reported.
Lengthening the exhale relative to the inhale, without changing breathing rate, raised RMSSD and high-frequency heart rate variability, consistent with greater cardiac vagal activity. High-frequency heart rate variability stayed elevated for about four minutes after the task.
Study details
Design. Within-subjects laboratory study; 28 healthy adults (16 aged 21–28, 12 aged 66–80) breathed at their own natural rate, cued for equal (1:1) or exhale-twice-as-long (2:1) timing.
Caveats. Small sample, single session. Participants achieved an exhale-to-inhale ratio of about 1.33 rather than the cued 2:1. Breathing was at natural, not slow, rates. A 2024 review (Meehan 2024) notes that everyone did the equal-breath condition first, partly confounding the ratio with order.
Parasympathetic activity, estimated from heart rate variability, increased significantly during prolonged expiratory breathing and was suppressed during rapid breathing.
Study details
Design. Within-subject laboratory study; 10 healthy men aged 21–28 did prolonged expiratory breathing (4 s in, 6 s out) and rapid breathing (1 s in, 1 s out), each after spontaneous breathing, with heart rate variability measured.
Caveats. Very small, men only, single session. Each pattern was compared only with the same person's spontaneous breathing just before it, in a fixed order, so the effect of the longer exhale cannot be separated from the slower pace (6 breaths per minute). The author notes heart rate variability is an indirect measure with clear limitations.
The inhale-to-exhale ratio did not affect heart rate variability time- or frequency-domain measures, and the replication also found no effect on nonlinear measures. The authors' review notes that earlier studies disagree about the effect of the ratio.
Study details
Design. Two within-subject studies (original n = 26, replication n = 16) comparing a 1:2 with a 1:1 inhale-to-exhale ratio while breathing at 6 breaths per minute, with a review of earlier studies.
Caveats. Small samples and heart rate variability outcomes only (no mood measures). Suggests that at 6 breaths per minute a longer exhale may add little to heart rate variability beyond the slow pace itself.
Over twelve weeks of regular slow breathing, anxiety scores (PROMIS Anxiety) fell, but heart-rate-variability measures of physiological stress did not change. The longer-exhale group improved slightly more, but the difference between groups was small (d = 0.2) and not statistically significant.
Study details
Design. 12-week randomised, single-blinded trial; 100 healthy adults learned yoga-based slow breathing with either the exhale longer than the inhale or the exhale equal to the inhale, with instruction sessions and home practice tracked by smart garments.
Caveats. Both groups did slow breathing and there was no non-breathing control, so the fall in anxiety cannot be separated from expectation or instruction effects. Healthy adults only.
The pattern with the hold produced significantly greater decreases in salivary cortisol, but also greater decreases in RMSSD (a heart rate variability measure), than the pattern without it. Neither pattern significantly changed self-reported stress, arousal or mood.
Study details
Design. Randomised crossover pilot; 32 adults did slow breathing in a 4-6 pattern (4 s in, 6 s out) and a matched 4-4-6 pattern with a 4-second hold after inhaling.
Caveats. Pilot study with 32 participants. A supplementary high-frequency heart rate variability analysis did not replicate the RMSSD result. The authors suggest the hold may alter short-term heart–breathing dynamics.
There were no differences between the techniques in self-reported mood. Tactical breathing produced lower physiological arousal, while prolonged exhalation led to better task performance; the authors suggest tactical breathing may suit passive coping and prolonged exhalation active coping.
Study details
Design. Counterbalanced repeated-measures laboratory study; 30 healthy participants used tactical breathing or prolonged exhalation to manage arousal while doing a Stroop task under time pressure and rising white noise (77–89 dB).
Caveats. Small lab study. Published online in 2020; issue dated 2021. The full text is paywalled, so the exact breath timings used could not be confirmed; tactical breathing is commonly taught as a box-style pattern with holds, but the abstract does not say so. The authors note that evidence for tactical breathing is limited.
Breathing and the brain talk in both directions. In mice, a small group of breathing-rhythm neurons connects directly to a centre for arousal. In people, nasal breathing has been linked to rhythms in emotional and memory regions, and, in one small study, trained slow breathing to better sustained attention.
Removing about 175 specific neurons left breathing intact but increased calm behaviours and reduced time in aroused states. These neurons connect to the locus coeruleus, a brain centre involved in attention, arousal and panic. This points to a direct link between breathing circuits and arousal.
Study details
Design. Laboratory study in mice. A small group of neurons was genetically removed from the preBötzinger complex, the brainstem's main breathing-rhythm generator.
Caveats. A study in mice. It identifies a possible pathway but does not test breathing exercises in people.
Natural breathing through the nose synchronised electrical activity in smell-related (piriform) cortex, the amygdala and the hippocampus, areas involved in emotion and memory. The effect faded when breathing switched to the mouth. In healthy volunteers, fearful faces were recognised faster and memory retrieval was more accurate during nasal inhalation.
Study details
Design. Recordings from electrodes implanted in the brains of people with epilepsy (7 patients in the main analyses), plus behavioural experiments in healthy volunteers.
Caveats. Brain recordings come from a small number of people with epilepsy. The behavioural effects were measured in brief laboratory tasks. The study is about the timing of natural breaths, not a breathing practice.
After training, the breathing group had lower negative affect than at baseline (the difference from the control group was only marginal) and lower salivary cortisol, while the control group's cortisol did not change. Sustained attention improved more in the breathing group, although the control group also improved.
Study details
Design. Controlled trial, 40 healthy adults (employees of an IT company in Beijing). The paper calls it randomised, but its methods say participants were assigned by alternating order of registration. The breathing group had 20 coached diaphragmatic breathing sessions over 8 weeks; the control group had no training.
Caveats. Small sample (39 analysed). Groups were formed by alternating registration order, not true randomisation. The control group did no alternative activity. Training was coached, used a feedback device and was very slow (about 4 breaths per minute).
Compared with mouth breathing, nasal breathing was associated with lower mean and diastolic blood pressure and a higher high-frequency (parasympathetic) contribution to heart rate variability. Systolic blood pressure and heart rate did not differ.
Study details
Design. Randomised-order crossover; 20 young adults (median age 18) breathed nose-only and mouth-only for 5 minutes each at rest.
Caveats. Small sample of young adults; 5-minute conditions with breathing paced to each person's own natural rate, not slowed breathing practice. Differences were modest.
Slow breathing before bed is associated with better self-reported sleep in several small studies, including one where people used an app for fifteen minutes each evening. What happens on sleep-lab recordings is less clear. We built Ready to rest for the wind-down, hoping it helps you sleep a bit better.
Compared with social media use, slow-paced breathing improved self-reported sleep quality (Pittsburgh Sleep Quality Index). It also increased overnight cardiac vagal activity, a heart rate variability marker of parasympathetic activity.
Study details
Design. Randomised controlled trial, 64 healthy young adults analysed (70 enrolled). The breathing group did 15 minutes of smartphone-app-guided slow-paced breathing (about 6 breaths per minute) each evening for 30 days. The control group spent the same time on social media.
Caveats. Young, healthy participants (mean age 22). Sleep quality was self-reported, with no polysomnography. Smartphone use before the study was not controlled.
People with insomnia had lower high-frequency (vagal) heart rate variability than good sleepers. When they practised slow paced breathing for 20 minutes before bed, they fell asleep sooner, woke less often and had higher sleep efficiency.
Study details
Design. Laboratory study, 14 people with self-reported insomnia and 14 good sleepers. Heart rate variability was measured during paced breathing at 0.1 Hz (6 breaths per minute) and 0.2 Hz, and night-time sleep was recorded by polysomnography.
Caveats. Very small sample (14 per group). Insomnia was self-reported, not clinically diagnosed.
Self-reported sleep duration and sleep quality improved after slow breathing before bedtime. Results from objective sleep measures (actigraphy and polysomnography) were inconclusive. Studies that measured heart rate variability found that slow breathing affected both parasympathetic and sympathetic activity.
Study details
Design. Systematic review of 9 studies (457 participants) of slow breathing at 10 breaths per minute or fewer, practised before bedtime.
Caveats. Few studies. The objective sleep findings were inconclusive, and three of the studies that measured sleep objectively used one-day protocols. The authors call for longer, higher-quality trials.
In people with raised blood pressure, regular slow breathing is associated with modest reductions. Results vary a lot between studies, and none of this is a substitute for care from your doctor, but there are indications that reducing your stress through breathwork may aid blood pressure.
Slow breathing at 10 breaths per minute or fewer (device-guided and pranayama trials pooled) was associated with a modest reduction in blood pressure: on average about 5.6 mmHg systolic and 3.0 mmHg diastolic.
Study details
Design. Systematic review and meta-analysis of 17 randomised studies in people with hypertension or prehypertension. Participants did slow breathing at 10 breaths per minute or fewer, for at least 5 minutes on at least 3 days a week, for 4 weeks or more.
Caveats. Results varied widely between studies. Participants had raised blood pressure, so the findings may not apply to people with normal blood pressure.
Alternate-nostril breathing was associated with larger reductions in systolic and diastolic blood pressure than no intervention or placebo. Heterogeneity between trials was very high (I² 87–93%), so the authors urge caution in interpreting the results.
Study details
Design. Systematic review of 14 studies (1,377 participants), with a meta-analysis of 6 randomised controlled trials (525 participants), of alternate-nostril breathing alone or within yoga programmes.
Caveats. Very high heterogeneity; most studies were not double-blinded; some combined alternate-nostril breathing with other yoga practices. The authors call for high-quality randomised trials.
One 5-minute session did not lower blood pressure compared with the control exercise. During recovery, heart rate variability shifted toward greater parasympathetic activity (higher high-frequency and lower low-frequency power) compared with control.
Study details
Design. Randomised controlled trial; 70 adults with essential hypertension did 5 minutes of Bee-Humming Breathing (n = 35) or a placebo slow-breathing exercise (n = 35), with blood pressure and heart rate variability measured before, during and after.
Caveats. Single short session in people with hypertension, so results may not apply to healthy users. Published online in 2020; issue dated 2021.
Heart rate and systolic blood pressure fell after 4-7-8 breathing in both groups. In the group without sleep deprivation, high-frequency heart rate variability rose and low-frequency power fell.
Study details
Design. Before-and-after study; 43 healthy 19–25-year-olds (22 sleep-deprived, 21 not) did three sets of six 4-7-8 cycles, with heart rate, blood pressure and heart rate variability measured before and immediately after.
Caveats. No comparison condition without the breathing exercise, so the changes could partly reflect resting quietly. Immediate effects only; small, mostly female sample.
Box breathing, 4-7-8, alternate-nostril breathing, humming and pursed lips each have a long history. Some have been compared head to head; most have only small studies behind them. Here is what we found.
Breathing at 6 breaths per minute increased heart rate variability more than square or 4-7-8 breathing, with small to medium effects. None of the conditions meaningfully changed blood pressure or mood, and 6 breaths per minute led to mild over-breathing.
Study details
Design. Within-subject laboratory study; 84 college students did square (box) breathing, 4-7-8 breathing, 6 breaths per minute with a 4:6 inhale-to-exhale ratio, and 6 breaths per minute with a 5:5 ratio, with heart rate variability, end-tidal CO₂, blood pressure and mood measured.
Caveats. Single session in college students, with each pattern tried once. The authors note that square and 4-7-8 breathing have little prior empirical support and call for multi-week studies.
During post-exercise recovery, box breathing was associated with higher heart rate and higher perceived exertion than 6 breaths per minute. Time for heart rate to return to baseline did not differ significantly between protocols.
Study details
Design. Randomised crossover; 40 physically active university students used spontaneous breathing, box breathing (4-4-4-4) or 6 breaths per minute (5 s in, 5 s out) during recovery after 15-minute high-intensity interval cycling sessions.
Caveats. Applies to recovery straight after hard exercise, not to resting practice. Young, active adults only; single sessions.
Neither technique changed standard heart rate variability measures compared with resting breathing. Effects on stress and mood depended on sex: 4-7-8 was associated with less stress and negative affect in women, and Nadi Shodhana with greater reductions in men.
Study details
Design. Analyst-blinded randomised crossover; 34 university students did 10 minutes each of 4-7-8 breathing, Nadi Shodhana and resting breathing, a week apart, with heart rate variability and questionnaires.
Caveats. Small sample, single 10-minute sessions. Published online ahead of print (September 2026), so no volume or pages yet. The sex-specific results come from interaction analyses and need replication.
Heart rate variability (total, low- and high-frequency power) was higher after both alternate-nostril breathing and plain paced breathing than at baseline, with no shift in autonomic balance. The authors suggest the effects of alternate-nostril breathing were mainly driven by the slow breathing rate.
Study details
Design. Within-subject laboratory study; 20 healthy adults new to yogic breathing did 30 minutes of alternate-nostril breathing and 30 minutes of paced breathing, both at 5 breaths per minute, in random order.
Caveats. Small, single session, people new to the technique; results may differ in experienced practitioners.
Nasal nitric oxide increased 15-fold during humming compared with quiet exhalation. In the model, oscillating airflow greatly increased gas exchange between the sinus and the nasal cavity.
Study details
Design. Laboratory measurement in 10 healthy subjects: nasal nitric oxide during humming compared with quiet single-breath exhalation at a fixed flow rate, plus a two-compartment model of the nose and sinus.
Caveats. Short research letter with 10 participants. It measured nitric oxide in exhaled nasal air, not health or wellbeing outcomes; the authors said any therapeutic effects should be investigated.
The included studies pointed to parasympathetic dominance with Bhramari and some encouraging physiological effects, but their methodological quality was rated very low and none were randomised trials.
Study details
Design. Systematic review of studies on Bhramari pranayama published to May 2016; 6 studies met the criteria (two on the cold pressor test, and one each on heart rate and blood pressure, EEG, inhibitory response and tinnitus).
Caveats. Only 6 small, heterogeneous, non-randomised studies; the authors call for large, properly designed randomised trials. Published online in 2017; issue dated 2018.
Humming produced slower, more stable breathing clustered near 0.1 Hz (about six breaths a minute) and was associated with higher heart rate variability than rest. Blocking the sound with noise-cancelling earphones made no difference; the authors conclude the effect comes from the slow pace set by the extended exhale rather than the vibratory sound. Self-rated stress and relaxation did not differ between conditions.
Study details
Design. Within-subject study with randomised session order; 24 healthy adults did rest, deep breathing, humming breathing, and humming with noise-cancelling earphones over five consecutive days.
Caveats. Preliminary study with 24 participants; breathing measures were estimated from heart rate variability rather than recorded directly. Published online ahead of print (February 2026), so no volume or pages yet.
Using pursed-lips breathing during exercise lowered minute ventilation and breathing rate compared with exercising without it. It made no significant difference to six-minute walk distance, and it is still unclear who benefits.
Study details
Design. Systematic review and meta-analysis of 8 crossover, randomised and quasi-randomised trials of pursed-lips breathing used during exercise by people with COPD (databases searched to May 2016).
Caveats. People with COPD, not healthy adults. Only 8 studies, with differing samples and exercise protocols; the authors call for better-quality studies. Looks at use during exercise, not as a standalone calming practice.
In obstructive lung disease, low-quality evidence suggests pursed-lip breathing may moderately reduce breathlessness when measured within 3 months of starting, although the true effect could be substantially larger or smaller.
Study details
Design. Systematic review with meta-analysis of 13 randomised controlled trials and 2 randomised crossover trials of non-drug, non-exercise interventions for adults with stable chronic lung disease, compared with usual care.
Caveats. People with chronic lung disease, not healthy adults. Evidence rated low quality, with a wide confidence interval. The review covers many non-drug interventions, not pursed-lip breathing alone.
Comfort comes first. Breathe gently, never strain, and stop if you feel dizzy, light-headed or short of breath.
08 · References
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Every citation was checked against PubMed, Crossref and the publisher’s record in October 2026. Summaries are ours, written to stay faithful to each paper’s abstract or full text.
