The Diaphragm in Body Psychotherapy: Emotional Regulation Through Breathing

Among all the muscles in the human body, one stands out for its quiet power: the diaphragm. Invisible to the eye but essential to life, it doesn’t just keep us breathing – it also regulates energy, emotions, focus, and inner clarity. It is a true psycho-physical hub, functioning as an accelerator, a brake, and even a container of our deepest body memories.

The diaphragm is not just the engine of respiration – it is also the muscle that supports us in transitions: between activation and relaxation, tension and release, closure and openness.

In this article, we explore its function from physiological and psychological angles, integrating insights from Erik Erikson’s developmental psychology and the Bodynamic system, which unites body and psyche into one functional process【1】.

The Diaphragm Across Developmental Stages

Over the course of our early development, the diaphragm plays a role far beyond breath. It helps shape how we relate to ourselves and the world around us.

In the first months of life - during what Erikson called the phase of basic trust【2】– deep, diaphragmatic breathing supports the infant’s emerging sense of safety and containment. The rhythm, presence, and warmth of a caregiver are internalized not only through emotional contact but also through the breath. When contact is inconsistent, the diaphragm may begin to hold tension – storing early bodily imprints of insecurity.

Between ages one and three, children enter the stage of autonomy. Here, the diaphragm begins to support the growing surge of “I want to do it myself!” If the child is supported in this exploration, the breath expands and the diaphragm remains mobile. But if the child experiences shame or excessive control, the diaphragm may tighten to contain emotional intensity that cannot yet be self-regulated.

Between ages three and six, the child moves into initiative. Now the diaphragm becomes a true modulator of energy. If it is free and mobile, it supports creativity, action, and emotional expression. But if blocked, it may suppress not only breath, but also desire, frustration, and enthusiasm. This tension, often held silently in the body, may resurface years later as anxiety or bodily discomfort.

The Diaphragm as Accelerator

When the diaphragm works well, it gives us energy. Each deep breath increases oxygen delivery to the cells, boosting ATP production – the cellular fuel that powers physical and mental activity【3】. Rhythmic breathing directly stimulates parts of the brain responsible for alertness and focus【4】.

The diaphragm also works with deep abdominal muscles to stabilize the core. This improves posture and reduces unnecessary physical effort. When our breath flows and the body is grounded, we feel strong, centered, and ready for action.

A fascinating phenomenon related to this is physiological coherence: when the rhythm of breath, heartbeat, and nervous system are synchronized, we gain access to clarity, responsiveness, and emotional balance【5】.

The Diaphragm as Natural Brake

At the same time, the diaphragm is a braking system. Slow, conscious exhalation sends calming signals through the nervous system. Cortisol levels drop【6】, the heart rate slows down, and the body shifts into a state of “rest and digest.”

This is mediated by the vagus nerve, which runs through the diaphragm and is activated during exhalation. Through this mechanism, we can calm the emotional brain (limbic system), reducing anxiety, frustration, and overreaction. It’s a built-in self-regulation system that we often forget to use.

In trauma or chronic stress, the diaphragm tends to become rigid and contracted【7】. This is a protective reflex – the body holds back, shuts down, or freezes. Learning to re-educate the diaphragm – through breath, touch, and movement – can help shift us out of blocked states and return us to an inner sense of safety.

Experience: Breathing into the Side Ribs

A simple yet powerful somatic exercise from the Bodynamic method helps reconnect with the diaphragm and improve emotional regulation. It's called Breath into the Side Ribs.

Find a quiet space and sit or lie down comfortably. Place your hands on the sides of your ribcage, just below your armpits. Begin to breathe slowly through your nose, directing the breath outward into your hands. Imagine your ribs expanding like a concertina or accordion. As you exhale, feel the hands return gently inward with the natural movement of your ribcage. Repeat for several minutes, letting your body find its own rhythm.

Practiced regularly, this exercise makes the diaphragm more supple, helps release emotional tension, and increases your sense of calm and embodied presence.

Special thanks to Bodynamic International for this integrative breath and awareness practice.

The Diaphragm and Emotional Memory

In body psychotherapy, it is often observed that releasing tension in the diaphragm leads to strong emotional reactions – crying, trembling, images, or memories. That’s because breathing is intimately linked to implicit memory – the nonverbal, body-stored part of experience【8】. Releasing the diaphragm may also release frozen emotions that are waiting for a safe space to emerge and be integrated.

What Research Says

Recent studies confirm what somatic practices have long understood.

A diaphragmatic breath training study showed that just eight weeks of practice significantly reduced cortisol, improved attention, and decreased negative emotional states【9】.

Other studies show that breathing influences the central nervous system, intracranial pressure, pain perception, and cerebral circulation【10】. Good breathing isn’t just about physical health – it’s a gateway to holistic well-being.

In Summary

The diaphragm is our internal bridge muscle – between activation and rest, body and psyche, past and present.

When it functions freely, it brings energy and clarity. When it softens, it guides us toward rest and recovery. And when it opens, it often reveals hidden parts of ourselves.

To train it – or more accurately, to listen to it – is a simple but transformative practice. Just a few minutes a day can make a profound difference. One breath at a time, the body reminds us there is another way to be in the world: calmer, more present, more alive.

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References

1. Marcher, L. & Fich, S. (2009). Body Encyclopedia – Bodynamic Analysis

2. Erikson, E. (1950). Childhood and Society

3. Ma, X., Yue, Z., Gong, Z., et al. (2017). The effect of diaphragmatic breathing on attention, negative affect and stress

4. Jerath, R., Jensen, M. (2025). Cardio-Respiratory-Cortical-Limbic Network

5. Thayer, J.F. et al. (2012). Heart rate variability and health: A neurovisceral integration perspective

6. Streeter, C.C., Gerbarg, P.L., et al. (2012). Effects of yoga on the autonomic nervous system...

7. Levine, P. (2010). In an Unspoken Voice: How the Body Releases Trauma and Restores Goodness

8. van der Kolk, B. (2014). The Body Keeps the Score

9. Ma et al., see above

10. PMC 6070065 – The Influence of Breathing on the Central Nervous System