The Hering-Breuer reflex, which regulates breathing based on lung stretch, plays a vital role in managing stress and anxiety. During Bathysmed dives, this reflex is intentionally activated to induce relaxation. By exploring this phenomenon in a therapeutic context, particularly for individuals dealing with intense stress, it becomes evident that targeted scuba diving exercises can be a powerful tool for improving mental and emotional well-being.

The Hering-Breuer Reflex: A Key Mechanism in Stress Management

The Hering-Breuer reflex is an essential physiological phenomenon, often underestimated, but fundamental in regulating breathing and, by extension, stress management. Discovered by physiologists Josef Breuer and Ewald Hering in the 19th century, this reflex highlights the close connection between the respiratory system and the autonomic nervous system.

What Is the Hering-Breuer Reflex?

The Hering-Breuer reflex is a protective mechanism involved in breathing regulation. It relies on the activation of stretch receptors located in the lungs, specifically in the smooth muscles of the bronchi and alveoli. These receptors detect lung expansion during inhalation and send signals to the brainstem via the vagus nerve (cranial nerve X).
When the lungs reach a certain stretch capacity, this reflex inhibits the inspiratory respiratory center in the medulla oblongata, causing a shift to exhalation. This mechanism prevents lung overexpansion and ensures a rhythmic, harmonious breathing pattern.

A Role in Stress Management

The Hering-Breuer reflex does more than prevent lung overdistension; it also contributes to modulating autonomic nervous system activity, which is especially relevant in stress contexts:

1. Parasympathetic Regulation: By slowing the breathing rate, this reflex promotes activation of the parasympathetic nervous system, responsible for “rest and digest” functions. This lowers heart rate and blood pressure—physiological markers of stress.
2. Impact on Heart Rate Variability (HRV): Slow, controlled breathing, often employed in relaxation techniques such as sophrology or heart coherence training, stimulates this reflex and enhances HRV, a key indicator of stress resilience.
3. Calming Effect: By prolonging exhalation, the Hering-Breuer reflex fosters a state of calm. This observation underpins many therapeutic practices based on breathing, such as yoga, meditation, and therapeutic diving, where slow, controlled breathing is essential.

Applications in Stress Management Practices

In therapeutic settings, the Hering-Breuer reflex can be harnessed to help manage stress and anxiety. Here are some approaches that utilize this mechanism:

1. Caycedian Sophrology: Controlled breathing exercises in this method stimulate the reflex to reduce physical and emotional tension.
2. Heart Coherence Training: By synchronizing breathing to a rhythm of 5–6 cycles per minute, this reflex is repeatedly activated, inducing relaxation.
3. Bathysmed Diving: Diving enforces slow, steady breathing, making it particularly effective for activating this reflex and calming the nervous system. Many Bathysmed exercises target this reflex, making the activity ideal for individuals with chronic stress.

The Reflex’s Role in Activating the Vagus Nerve

The Hering-Breuer reflex activates the vagus nerve, inducing a relaxation response that slows heart rate and promotes a sense of calm. During Bathysmed diving exercises, this process is amplified because deep, controlled breathing underwater intensifies parasympathetic activation.

Clinical Application: The Hering-Breuer Reflex in Therapeutic Diving

Case Study: Anne, a 42-year-old corporate executive experiencing burnout
After several months of intense workplace stress, Anne exhibits symptoms of burnout: chronic fatigue, insomnia, irritability, and anxiety attacks. She decides to join a Bathysmed diving program combining principles of mindful breathing and immersion in a soothing environment.

Intervention: Immersion and Controlled Breathing

In her first session in a controlled environment (pool or lagoon), the instructor guides Anne through slow, deep breathing using a regulator. Scuba breathing naturally extends inhalation and exhalation, directly activating the Hering-Breuer reflex. Combined with the water’s hydrostatic pressure, this reflex stimulates the parasympathetic system, inducing immediate relaxation.
Over subsequent sessions in open water, Anne learns to adjust her breathing rhythm to her sensations. Focusing on her breath helps her redirect attention from anxious thoughts, akin to mindfulness techniques.

Observed Results

1. Immediate Effect: After each session, Anne reports a profound sense of calm. Measurements of her heart rate before and after dives show a significant decrease, with improved heart rate variability.
2. Long-Term Effect: After 10 sessions, Anne experiences fewer anxiety attacks and better sleep quality. She incorporates breathing exercises learned during diving into her daily routine, especially during stressful work situations.
3. Overall Well-Being: Anne describes a renewed connection with her body and improved emotional regulation, aiding her recovery.

Analysis and Outlook

In Anne’s case, Bathysmed diving acts as a catalyst by leveraging the Hering-Breuer reflex. The benefits stem from the combination of multiple factors:

• The aquatic environment, which enhances relaxation.
• Regulator-induced breathing patterns that extend exhalation and activate the parasympathetic system.
• The meditative aspect of the experience, grounding the diver in the present moment.

This example illustrates how a well-designed practice based on physiological mechanisms like the Hering-Breuer reflex can yield significant therapeutic outcomes. This model can be replicated in various contexts, including with groups suffering from post-traumatic stress or professionals under chronic mental strain.