Claim reviewed: Breathing slowed to about 6 breaths a minute increases the rest-related component of heart rate variability.
What do we know?
In a meta-analysis of 223 studies, voluntary slow breathing increased vagally mediated heart rate variability during breathing, immediately after a session and after multi-session programmes. Biofeedback training that teaches pacing to heart rhythm was also linked to a large reduction in self-reported stress and anxiety.
What don't we know?
The effect comes from slower breathing; no effect of the sound itself has been shown. Some studies used device-based biofeedback; whether pacing with sound alone gives the same result has not been tested separately. Any advantage of searching for a personal breathing rate is outside this claim.
Wording we use in the app: Guides your breathing down to about six breaths a minute; slow breathing can support a body response linked to relaxation.
Sources (2)
Laborde ve ark. 2022 · Meta-analysis · 223 studies
A systematic review and meta-analysis of 223 studies on voluntary slow breathing and heart rate variability. Vagally mediated heart rate variability increased during slow breathing, immediately after a single session and after multi-session programmes.
Laborde S, Allen MS, Borges U, Dosseville F, Hosang TJ, Iskra M, Mosley E, Salvotti C, Spolverato L, Zammit N, Javelle F. Effects of voluntary slow breathing on heart rate and heart rate variability: A systematic review and a meta-analysis. Neurosci Biobehav Rev. 2022;138:104711. doi:10.1016/j.neubiorev.2022.104711 PMID 35623448 Go to source
Goessl ve ark. 2017 · Meta-analysis · 24 studies · 484 participants
A meta-analysis of 24 studies (484 participants) on heart rate variability biofeedback training: a large reduction in self-reported stress and anxiety (g = 0.83 against controls). The authors call for better-controlled studies.
Between-groups g = 0.83
Biofeedback paces breathing to heart rhythm measured by a device; it is not the same as pacing with sound alone.
Goessl VC, Curtiss JE, Hofmann SG. The effect of heart rate variability biofeedback training on stress and anxiety: a meta-analysis. Psychol Med. 2017;47(15):2578-2586. doi:10.1017/S0033291717001003 PMID 28478782 Go to source
Last reviewed: 3 October 2026 · Next review: 3 April 2027