The research, and its limits

What this approach draws on, what the evidence supports, and where it stops.

Human Again draws on research into stress and recovery, psychological detachment, and deliberate respiratory practices. That research informs the approach. It does not establish the effectiveness of the complete program, and this page says which is which.

Sustained stress carries measurable costs

Research connects stress and stress-response recovery with cardiovascular risk. [9, 10] Studies examine different exposures and outcomes; these findings do not establish that this program prevents cardiovascular disease.

Recovery is a distinct process, and it can be improved

Recovery research examines experiences such as mentally disengaging from work, relaxation, positively challenging activities and choice over free time. Their relationships with wellbeing and work outcomes differ. [1, 2, 4] Studies also suggest that psychological detachment can improve through structured interventions. [3]

What respiratory training measurably changes

Slow breathing produces consistent autonomic change. Two independent meta-analyses report increased vagally-mediated heart rate variability during and after slow-breathing practice, [5, 6] alongside reduced systolic blood pressure and heart rate. [6]

What that does not establish is a reliable effect on how stressed a person feels. The same meta-analysis found only a marginal, non-significant reduction in negative emotion, with high variability between studies. [6] Nor does any of it establish lasting health benefits, or the effectiveness of psychophysiological respiratory training for professionals. [7]

What this doesn’t establish yet

No study tests this program. The evidence above supports its components, not the sequence they are used in.

Two claims I make elsewhere — that prolonged stress can change how a person breathes by default, and that cognitive and behavioral change costs more and holds less well under continuous demand — I describe as clinical observation rather than cite, because that is what they are.

I expect that to change. Testing the program properly is work I intend to do with university partners.

References

  1. Sonnentag, S., & Fritz, C. (2007). The Recovery Experience Questionnaire: Development and validation of a measure for assessing recuperation and unwinding from work. Journal of Occupational Health Psychology, 12(3), 204–⁠221. https://doi.org/10.1037/1076-8998.12.3.204
  2. Headrick, L., Newman, D. A., Park, Y. A., & Liang, Y. (2023). Recovery experiences for work and health outcomes: A meta-analysis and recovery-engagement-exhaustion model. Journal of Business and Psychology, 38, 821–⁠864. https://doi.org/10.1007/s10869-022-09821-3
  3. Karabinski, T., Haun, V. C., Nübold, A., Wendsche, J., & Wegge, J. (2021). Interventions for improving psychological detachment from work: A meta-analysis. Journal of Occupational Health Psychology, 26(3), 224–⁠242. https://doi.org/10.1037/ocp0000280
  4. Sonnentag, S., Cheng, B. H., & Parker, S. L. (2022). Recovery from work: Advancing the field toward the future. Annual Review of Organizational Psychology and Organizational Behavior, 9, 33–⁠60. https://doi.org/10.1146/annurev-orgpsych-012420-091355
  5. Laborde, S., Allen, M. S., Borges, U., Dosseville, F., Hosang, T. J., Iskra, M., Mosley, E., Salvotti, C., Spolverato, L., Zammit, N., & Javelle, F. (2022). Effects of voluntary slow breathing on heart rate and heart rate variability: A systematic review and a meta-analysis. Neuroscience & Biobehavioral Reviews, 138, 104711. https://doi.org/10.1016/j.neubiorev.2022.104711
  6. Shao, R., Man, I. S. C., & Lee, T. M. C. (2024). The effect of slow-paced breathing on cardiovascular and emotion functions: A meta-analysis and systematic review. Mindfulness, 15(1), 1–⁠18. https://doi.org/10.1007/s12671-023-02294-2
  7. Santino, T. A., Chaves, G. S. S., Freitas, D. A., Fregonezi, G. A. F., & Mendonça, K. M. P. P. (2020). Breathing exercises for adults with asthma. Cochrane Database of Systematic Reviews, Issue 3, CD001277. https://doi.org/10.1002/14651858.CD001277.pub4This review concerns breathing exercises in adults with asthma, including Buteyko among several techniques. It does not establish the effectiveness of Human Again for recovery in professionals.
  8. McEwen, B. S. (2008). Central effects of stress hormones in health and disease: Understanding the protective and damaging effects of stress and stress mediators. European Journal of Pharmacology, 583(2–⁠3), 174–⁠185. https://doi.org/10.1016/j.ejphar.2007.11.071
  9. Chida, Y., & Steptoe, A. (2010). Greater cardiovascular responses to laboratory mental stress are associated with poor subsequent cardiovascular risk status: A meta-analysis of prospective evidence. Hypertension, 55(4), 1026–⁠1032. https://doi.org/10.1161/HYPERTENSIONAHA.109.146621
  10. Richardson, S., et al. (2012). Meta-analysis of perceived stress and its association with incident coronary heart disease. American Journal of Cardiology, 110(12), 1711–⁠1716. https://doi.org/10.1016/j.amjcard.2012.08.004