Coherent breathing is the term Stephen Elliott introduced for slow, equal-ratio breathing at five breaths per minute. Six seconds in, six seconds out. The stated intent: coherent oscillations between heart rate, blood pressure, and breath.
Read that protocol description and it should sound familiar. Slow breathing around five to six breaths per minute is also what the Lehrer and Vaschillo group at Rutgers studied and called resonance frequency breathing. One real difference: resonance breathing is set to each person’s own rate. Coherent breathing fixes it at five.
Why two names exist
Resonance frequency breathing is the clinical research term. In a 2002 study, Evgeny Vaschillo, Paul Lehrer and colleagues had participants use biofeedback to drive their heart rate at a range of frequencies. The largest heart-rate oscillations came at roughly 0.055–0.11 Hz — about three to seven cycles a minute — and the exact frequency differed between individuals. The authors explained it as resonance in the cardiovascular system.
“High and low target-frequency oscillation amplitudes at specific frequencies could be explained by resonance among various oscillatory processes in the cardiovascular system.”
Coherent breathing came later as a consumer-facing framing. Stephen Elliott’s 2005 book The New Science of Breathpresented slow breathing at a single fixed rate to a non-clinical audience under a new name. The framing emphasized the subjective experience — feeling coherent, integrated — over the physiology.
Both terms persist. Researchers tend to use “resonance frequency breathing”; wellness practitioners and yoga teachers tend to use “coherent breathing.” Most of the research below is filed under the first name.
The protocol, in detail
Inhale through the nose for six seconds. Exhale through the nose (or pursed lips) for six seconds. No holds. Continue for three to ten minutes. That’s coherent breathing.
Five breaths per minute is the canonical rate. Some practitioners use six breaths per minute (5 seconds in, 5 out). Individual resonance frequency does vary: in Vaschillo et al. (2006), data from 56 adults showed a lower resonant frequency in taller people and in men, no relationship with age, weight or asthma, and a rate that stayed constant across 10 sessions of training.
The research model behind the protocol: the adult cardiorespiratory system has a fixed resonance frequency, and breathing near it produces large blood-pressure oscillations that can increase baroreflex sensitivity over time. That is how the field’s own practical guide states the premise (Shaffer et al., 2020).
Effects, by the literature
One caveat first: most of this research is on HRV biofeedback — resonance breathing with a live HRV display — not on fixed-rate coherent breathing. With that said:
- Vagally-mediated HRV rises during slow breathing, immediately after a single session, and after multi-session interventions — a 2022 meta-analysis of 223 studies.
- Self-reported stress and anxiety: a 2017 meta-analysis of 24 HRV-biofeedback studies (484 participants) found a large reduction, and called for more well-controlled studies.
- Asthma, the original clinical application: in a 94-person trial, both HRV-biofeedback groups were prescribed less medication than the control groups.
- Across 58 randomized studies (Lehrer et al., 2020, below), the largest effects were for anxiety, depression, anger and athletic or artistic performance, and the smallest for PTSD, sleep and quality of life.
“A significant small to moderate effect size was found favoring HRVB, which does not differ from that of other effective treatments.”
That is the honest size of it, from the field’s own leading researchers: small to moderate, comparable to other effective treatments rather than larger. It is also free, takes minutes, and stacks with everything else worth doing.
Why HRV Breathe uses “resonance”
We named the technique after the research term rather than the experiential framing. Resonance is what the literature above calls it. Coherent describes how the state feels. Both are correct; we use the research term because the rest of the app leans on that literature.
Practically: if you came here looking for coherent breathing, the “Resonance” technique in HRV Breathe is what you want. The app defaults to 6 BPM and lets you adjust to 5 or 7 BPM.
Finding your personal resonance rate
Individual resonance frequency varies, and practising at your own rate is the premise of the research protocol.
The clinical method is a resonance-frequency assessment: a practitioner paces you through several breathing rates while recording HRV, and compares the pattern of change across them. Shaffer et al.’s 2020 guide stresses comparing several candidate rates, not one reading, and fine-tuning after the first assessment.
The non-clinical method: start at 6 BPM (HRV Breathe’s default). If you find sustained sessions uncomfortable or breathy, try 6.5 or 7 BPM. If 6 BPM feels too brisk, try 5.5 or 5. Settle on whichever feels natural for a 10-minute sustained session. Comfort is not the same thing as resonance; it’s a reasonable starting point, not a measurement.
Practical recommendation
Don’t spend time deciding between “coherent” and “resonance.” They’re the same. Pick a rate between 5 and 7 BPM that feels sustainable and practice three to ten minutes daily. If you track HRV, watch the trend over a month and judge it yourself.
If you’ve been doing coherent breathing for years and want to keep using that term, by all means. Just know that’s exactly what HRV Breathe’s Resonance technique is doing under the hood.