RESEARCH · CYCLIC SIGHING
Cyclic Sighing — The Strongest Short-Breathwork Result
In the Balban et al. (2023) RCT, five minutes of daily cyclic sighing beat box breathing, cyclic hyperventilation, and mindfulness meditation on positive affect.
Updated April 2026·5 min read
TL;DR. In the Balban et al. (2023) RCT, five minutes of daily cyclic sighing beat box breathing, cyclic hyperventilation, and mindfulness meditation on positive affect.
The Stanford trial
Balban et al. (Cell Reports Medicine, 2023) ran a 28-day study comparing four five-minute practices: cyclic sighing, box breathing, cyclic hyperventilation with retention, and mindfulness meditation. The primary outcome was daily positive affect, with secondary outcomes on anxiety and respiratory rate.
Cyclic sighing — a double inhale followed by an extended exhale — produced the largest daily improvement in positive affect and reduction in respiratory rate. The effect grew week-over-week, with larger cumulative gains in weeks three and four than in weeks one and two.
Relevant research: Balban et al., 2023 (Cell Reports Medicine).
Why the physiological sigh
The mechanism is plausible: a double inhale reinflates collapsed alveoli, improving gas exchange, and the extended exhale is the strongest voluntary lever on parasympathetic activation. Spontaneous physiological sighs occur naturally every few minutes during quiet wakefulness — the intervention turns that background mechanism into an attended practice.
The result is one of the cleanest 'do one thing for five minutes' findings in the short-breathwork literature.
Relevant research: Balban et al., 2023 (Cell Reports Medicine); Yasuma & Hayano, 2004 (Chest).
Caveats worth stating
This is one trial, albeit a well-run one. Effects in a replication might be smaller. The comparison arms were all sensible — not placebo — which is part of why the result is interpretable, but it also means the absolute effect over baseline is unknown.
We cite this paper because it informs a deliberate design choice: cyclic sighing shows up as a default recommendation in Loam's stress and anxiety flows, but we describe the evidence honestly rather than as a miracle protocol.
How this shows up inside Loam
Other research pillars
Polyvagal theory · Slow breathing · Acceptance and Commitment Therapy · Self-compassion · Somatic experiencing · MBSR · Binaural beats.
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