What the breath changes in the body

Breathing is the only function of the autonomic nervous system that we can consciously control. Slow breathing (around six breaths per minute) goes hand in hand with higher heart rate variability and more parasympathetic activity (Zaccaro et al., 2018)^[2]. Fast, deep breathing, on the other hand, activates the sympathetic nervous system – heart rate and alertness rise.

Rebirth Breathwork uses both, one after the other: a phase of intense activation, followed by stillness and slow breathing. Many people experience deep relaxation afterwards. Research on controlled hyperventilation shows that people can consciously influence their stress response (Kox et al., 2014)^[6] – albeit with a different method.

Established, suspected, open

• Established: In randomised trials, breathwork interventions reduce self-reported stress with small to moderate effects (Fincham et al., 2023)^[1]. Short daily breathing exercises improve mood (Balban et al., 2023)^[3].
• Suspected: The shift from activation to rest works like training: the body experiences intensity and then finds its way back to rest.
• Open: There are only a few controlled studies specifically on rebirthing. Long-term effects have hardly been studied.

A central insight of modern trauma research: overwhelming experiences are remembered not only as a story but also as a bodily state – tension, freezing, hyperarousal. In The Body Keeps the Score (van der Kolk, 2014)^[8], Bessel van der Kolk describes how trauma shapes perception, the sense of one’s body and relationships. Peter Levine (Somatic Experiencing; Levine, 1997)^[9] emphasises that survival responses “stuck” in the body can be released through mindful body awareness. Pat Ogden links this with movement and posture in sensorimotor psychotherapy (Ogden et al., 2006)^[16]. Gabor Maté describes how chronic stress and early adversity are connected to physical health (Maté, 2022)^[18]; research on transgenerational transmission even explores possible epigenetic traces (Yehuda & Lehrner, 2018)^[21].

How common early adversity is and how it affects health is shown by the ACE Study (Felitti et al., 1998)^[19]: the more adverse childhood experiences, the higher the risk of later physical and mental illness.

Attachment and C-PTSD

Attachment theory (Bowlby, 1988)^[13] and the Still Face Experiment (Tronick et al., 1978)^[20] show how strongly our nervous system responds to the sensitivity of caregivers, even in infancy. Where this safety was repeatedly missing, complex trauma effects can develop: difficulties regulating emotions, a negative self-image and difficulties in relationships – today described as C-PTSD in the ICD-11 (Walker, 2013; Herman, 1992; Karatzias et al., 2019)^[10][14][23].

A model, not a certainty: polyvagal theory

Stephen Porges’ polyvagal theory (Porges, 2011)^[11] offers a helpful language for states such as fight/flight, freeze and social connection. However, some of its neurobiological assumptions are scientifically disputed (Grossman, 2023). We use it as a map for experience, not as a proven explanation.

Precisely because connected breathing is effective, it is not suitable for everyone. Not suitable in cases of: pregnancy, epilepsy or seizure disorders, severe cardiovascular disease or uncontrolled high blood pressure, recent surgery, glaucoma or retinal detachment, severe asthma, psychosis, bipolar disorder or acute mental health crises. If in doubt, please check with a doctor beforehand.

For Reiki, the evidence is growing: a meta-analysis of randomised trials (Guo et al., 2024)^[25] shows a clear reduction in anxiety; earlier reviews found indications of less pain and anxiety (Thrane & Cohen, 2014)^[26]. Several clinics now offer Reiki as a complementary therapy.

Two sides of neuroplasticity

Our nervous system learns through repetition – in both directions. What we experience often becomes easier to access: fear as well as safety. Working in a trauma-sensitive way therefore means repeating experiences of safety within intensity – in small steps, at your own pace.