What is breathwork?

Breathwork, or Pranayama, is a practice that has been around for thousands of years – even if the wellness trends are just jumping on board now. 

At its core, breathwork is simply the practice of paying attention to how you breathe. Pranayama uses different breathing techniques to influence your body, mind, and nervous system. 

Our bodies have two activations of the nervous system: Parasympathetic and Sympathetic. We can intentionally influence which system is present by practicing different techniques of breathing.

How Breathwork Affects the Nervous System

Parasympathetic Nervous System

This system is in control when we are relaxed. It is the “rest and digest” part of the nervous system. When there is a lack of stress hormone, the heart rate is at its resting state, and the body is calm. In breathwork, we can activate the Parasympathetic Nervous System by using specific techniques. These techniques typically include deep exhales, breath holding, and slow breathing. In breathwork, we call this activation “downregulation.”

Sympathetic Nervous System

On the contrary, the sympathetic nervous system is activated by stress in the body. We reference it as the “fight or flight” response system. The sympathetic nervous system is vitally important to get us through stressful times, like public speaking or competing in a 5k. To activate this system, we can use breathing techniques such as rapid breathing, hyperventilation, or the breath of fire. This is called “upregulation.”

The Physiological Effect of Breathwork

Heart Rate Variability (HRV)

Heart rate variability (HRV) is the time between heartbeats. Doctors use this metric to determine heart health.

Your heart responds to countless factors in your body, like stress, CO2 levels, blood pressure, emotional states, etc. This causes your heart rate to increase or decrease depending on varying levels of excitation. For example, your heart rate is higher during sprint training and lower during a Netflix marathon. This is because your body doesn’t need the same amount of blood pumping through your body at all times. 

HRV is a more specific measure than general heart rate, which doctors use to determine heart health.

Someone is considered to have “high HRV” when they can change their HRV more drastically. This means they can reach higher peak heart rates and lower lows.

High HRV is associated with better emotional regulation, autonomic flexibility, cardiovascular health, and resilience to stress.

HRV reflects how dynamically the sympathetic and parasympathetic nervous systems interact. Greater variability generally indicates stronger parasympathetic influence and better adaptability.

Better HRV = increased emotional regulation, heart health, and autonomic flexibility

Heart Coherence

An even better indicator of wellness than HRV is the concept of heart coherence.

Heart coherence is the physiological state in which the cardiac and respiratory systems become synchronized.

Physiologically, your cardiac system and respiratory rate (breathing rate) have a working relationship. The electrical impulses in your heart signal your lungs when to breathe. 

CO2 levels also play a factor in breathing rates, but more on that HERE. 

When your cardiac and cardiovascular systems are optimized, people experience greater emotional regulation, impulse control, and adaptability to stress.

Explore ground-breaking heart coherence research here.

Most people have arrhythmias in their heart coherence that they don’t even know about. Through the practice of MINDFUL BREATHING, you can begin to notice pauses or irregular patterns either in your breathing or your heartbeat. The smoother you breathe in and out, coupled with a regular, steady heartbeat, the healthier the relationship between lungs and heart.

Improved heart coherence = improved emotional regulation, impulse control, & adaptability to stress. 

Vagal Tone

Vagal tone is a measure of how effectively your body can activate its natural “calm down” system.

The Vagus Nerve is the longest in the body. It runs from the brain, down the side of the neck, all the way to the upper legs.

The vagus nerve is related to the parasympathetic nervous system. The vagus nerve helps signal the heart to slow when the body is safe and relaxed. It supports rest, recovery, and energy conservation.

Vagal tone refers to how efficiently the vagus nerve influences the heart and other organs to alter nervous system states. HRV is an indirect measure of vagal tone.

Breathwork has been proven to improve vagal tone. Read more about how this works HERE.

In diving, we use prolonged exhales and diaphragmatic breathing to strengthen vagal tone. With that comes increased resistance to stress, better digestion, and decreased inflammation.

Improved Vagal Tone = increased resistance to stress, better digestion, and decreased inflammation.

Quick Explanation of Carbon Dioxide (CO₂)

Here is how breathing actually works physiologically: 

• Inhaling brings in oxygen.
• The body detects increased CO2 levels, which signals exhalation
• Exhaling releases carbon dioxide.
• The body detects decreased CO2 levels, which signals inhalation 

Each breath is a perfect chemical balance of oxygen and carbon dioxide. 

Our bodies begin to breathe in (inhale) only when there is too much carbon dioxide in the body, not because there is too little oxygen.

Certain breathwork techniques increase CO2 levels intentionally in the body. These techniques include rapid breathing, breath holding, and hyperventilation. These can be incredibly dangerous for divers, which we will talk about BELOW.

Having higher tolerance to CO2 in the body is associated with reduced uncontrolled anxiety, improved breath control, and improved emotional regulation.

Improved CO2 tolerace = improved anxiety management, breath control, & emotional regulation

Why This Matters for Divers

Breathing is one of the few bodily functions we can consciously control underwater.

• The way you breathe directly affects:
  • Stress and anxiety levels
  • Air consumption
  • Focus and decision-making
  • Cardiovascular strain
  • Overall comfort underwater
  • Buoyancy 

Breathwork has so many benefits for divers; it requires its own blog post! Check back here soon for an in-depth review of how breathwork makes you a better diver. For more info on meditating underwater, check out this page.

Risks and Dangers of Breathwork

As with everything, there are inherent risks to breathwork. Most of the risks highlighted below are a result of breathwork techniques involving aggressive or forced breathing. In scuba diving, we focus on slow, deep breathing. I recommend divers not to participate in rapid, shallow, forced breathing before, during, or immediately after diving. 

Cardiovascular Strain

• Aggressive or forceful breathing may:
  • Increase strain on the heart
  • Trigger arrhythmias
  • In rare cases, it can contribute to cardiac events

Increased Blood Pressure

• Forceful breathing techniques can temporarily elevate blood pressure.
• Higher risk for individuals with hypertension.

CO₂ Retention

Some breathwork techniques focus on the concept of “CO2 loading,” which essentially increases the body’s tolerance to higher CO2 levels. This can lead to respiratory alkalosis (when the blood becomes more alkaline). 

CO2-related risks include:  

• Slowing or suppressing breathing too much may contribute to inadequate ventilation.
• At depth, increased gas density makes breathing more difficult.
• This can lead to:
  • Air hunger
  • Anxiety
  • Dizziness
  • Impaired judgment
• Elevated CO₂ can intensify the effects of nitrogen narcosis.

Best Breathwork Practices for Divers

Keep It Simple

• Focus on diaphragmatic breathing only.
• Use gentle, natural breaths.

Emphasize Relaxed Exhalation

• Allow the exhale to be slightly longer than the inhale.
• Never force the breath.

Maintain Normal Ventilation

• Avoid both overbreathing and underbreathing.

Stay Within Recreational Diving Standards

• Continue breathing continuously.
• Do not hold your breath.

Key Breathwork Takeaways

• Breathwork can improve HRV, vagal tone, and stress resilience.
• A gentle, prolonged exhale may help divers relax and descend more comfortably.
• Diaphragmatic breathing is the safest and most practical approach.
• Aggressive or improperly applied breathwork can create significant risks underwater.
• For scuba diving, simple and relaxed is best.

Conclusion

Breathwork gives divers a powerful tool to influence stress, focus, and comfort both above and below the surface. 

By understanding how breathing affects the nervous system, heart, and carbon dioxide levels, you can use simple techniques like diaphragmatic breathing and relaxed exhalation to become a calmer and more efficient diver. 

While advanced breathwork methods can carry risks, especially underwater, the basics are both safe and highly effective. 

When it comes to scuba diving, the most beneficial breathing technique is also the simplest: slow down, breathe deeply, and let your body relax.

Want to learn more? Check out the blog here to read about everything diving in Playa del Carmen, Mexico.

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