In a September 30, 2026 workplace trial, reported benefits were not accompanied by significant changes in selected physiological measures.
The new trial tested a combination
Twenty-nine adults in France, averaging about 29 years old, completed both conditions in randomized order. After a laboratory stress task, they received either 15 minutes of paced breathing guided by blue light and sound, or rest in darkness.
The model estimated approximately 31% lower subjective stress, 0.84 points less sleepiness and 1.85 points higher positive affect with the intervention. Negative affect, HRV and selected EEG outcomes showed no significant intervention effect.
Separate breathing-only and light-only groups were absent. The small sample and lack of correction for multiple hypothesis testing also limit confidence. Human design Group, the product developer, helped fund the work and employed several authors; co-authors without that affiliation conducted the statistical analyses.
A comparison that found an HRV difference
A November 2025 experiment in 80 healthy university students tested five minutes of light-guided resonant breathing against passive rest after two kinds of laboratory stressor. The interventions were reversed after the second stressor.
Here, breathing increased RMSSD, an HRV measure, during recovery after both stressors. Participants rated it as more enjoyable; after cognitive stress, they also reported lower strain. That is useful adjacent evidence, but its shorter intervention, different stressors and student population prevent treating it as a replication of the new combined-device trial.
The authors reported Austrian Research Promotion Agency support and no competing interests. The comparison helps keep the question specific: which outcome changes, with which intervention, in which setting?
Clinical results also depend on the outcome
Another 2025 randomized crossover study analyzed 78 psychiatric inpatients with persistent somatic symptoms after allocating 98 participants to the interventions. It compared light-guided resonant breathing with sham light therapy, twice daily for five weekdays per condition, alongside inpatient care.
The primary outcomes of somatic well-being and arousal did not show an intervention-specific improvement. Some secondary outcomes, including reported anxiety and insomnia symptoms, improved, and HRV changed during sessions. The authors reported no breathing-related adverse effects; ratings of light-related glare were low.
Primary and secondary outcomes should retain their labels: a favorable secondary finding does not turn an unsuccessful primary comparison into a uniformly positive trial. This study also received Austrian Research Promotion Agency funding and declared no competing interests.
What the comparison leaves open
These studies involve different populations, controls and timescales. Their results should not be combined informally into a single claim that a breathing protocol changes stress physiology for everyone. Nor does a nonsignificant physiological result establish that a participant's reported relief was unreal.
A useful follow-up would separate the components, use a convincing comparison condition and examine whether any benefit persists or improves an actual work task. Until then, the responsible interpretation stays close to the outcomes: short experimental sessions, particular measurements and questions still awaiting stronger tests.