Oxygen’s Role in the Body and Brain

Breathing: More Than Just Oxygen In, Carbon Dioxide Out

Have you ever taken a deep breath, expecting to feel energised, only to feel lightheaded instead? Or maybe you've tried to “breathe deeply” during a stressful moment, but it only made things worse?

Most people assume that breathing is simply about inhaling oxygen and exhaling carbon dioxide, but the reality is far more complex. Three key gases - oxygen (O₂), nitric oxide (NO), and carbon dioxide (CO₂) - play fundamental roles in how our body produces energy, regulates circulation, and maintains homeostasis.

By understanding the relationship between these gases and practising intentional breathwork, you can influence how your body manages energy, stress, and recovery. Let’s break down how each gas functions, how they work together, and how breathwork can help optimize this delicate balance.

Oxygen (O₂): Essential for Energy & Cognitive Function

Oxygen is the body’s fuel. Without it, cells cannot produce energy efficiently. Every time you breathe in, oxygen enters your lungs, binds to haemoglobin in your red blood cells, and is transported to every cell in your body. Inside those cells, oxygen plays a key role in ATP production, which powers everything from muscle contractions to brain function.

How O₂ Affects the Brain & Body

• Cellular Energy Production: Oxygen is the final electron acceptor in the electron transport chain, a process that generates ATP (adenosine triphosphate), the primary energy currency of the body.
• Cognitive Function: The brain consumes 20% of the body’s oxygen supply, fueling memory, focus, and learning.
• Physical Performance: Muscles require oxygen for sustained energy production, especially during aerobic exercise. Low oxygen efficiency can lead to fatigue, brain fog, and decreased endurance.

Key Insight: More oxygen isn’t always better. Your ability to use oxygen efficiently is what matters. This is where nitric oxide (NO) and carbon dioxide (CO₂) come into play.

Nitric Oxide (NO): The Oxygen Highway Regulator

Nitric oxide acts as a traffic controller for oxygen, ensuring it gets where it needs to go efficiently. It signals blood vessels to dilate, improving circulation and allowing oxygen-rich blood to reach tissues and organs more effectively. If you've ever tried a pre-workout drink, you'll notice they usually contain l-citrulline or L-arginine as "pump" ingredients. These are precursors to the production of nitric oxide.

How NO Enhances Oxygen Delivery & Nervous System Function

• Vasodilation: NO relaxes blood vessels, increasing oxygen delivery to muscles and the brain.
• Cardiovascular Health: Higher NO levels reduce blood pressure and improve circulation.
• Nervous System Regulation: NO acts as a neurotransmitter, influencing mood, cognition, and relaxation.

The Role of Nasal Breathing in NO Production

Did you know that breathing through your nose increases nitric oxide production? The paranasal sinuses naturally produce NO, which is inhaled directly into the lungs when you breathe nasally. This boosts oxygen absorption, immune function, and relaxation.

Key Insight: Mouth breathing bypasses nitric oxide production, reducing oxygen efficiency and increasing stress levels.

Carbon Dioxide (CO₂): More Than Just a Waste Product

Most people think of carbon dioxide as something to get rid of, but it’s actually a critical regulator of breathing and oxygen delivery.

Why CO₂ is Essential for Optimal Breathing

• Oxygen Release (Bohr Effect): Higher CO₂ levels help haemoglobin release oxygen into tissues. If CO₂ is too low (due to overbreathing), oxygen remains bound to haemoglobin and doesn’t reach your cells efficiently.
• Blood pH Regulation: CO₂ is essential for maintaining the body's acid-base balance through the bicarbonate buffer system.
• Respiratory Drive: Your brain monitors CO₂ levels (not oxygen levels) to regulate breathing. Higher CO₂ tolerance improves breath control and nervous system resilience.

How Overbreathing Disrupts CO₂ Balance

Many people breathe too fast and too shallow, expelling too much CO₂. This leads to:

• Dizziness, brain fog, and fatigue
• Narrowed blood vessels, reducing oxygen to the brain
• Anxiety and panic attacks due to dysregulated breathing

Key Insight: CO₂ isn’t just waste. It regulates oxygen use, pH balance, and nervous system function. Training your body to tolerate higher CO₂ levels improves oxygen efficiency and stress resilience.

Breathwork Strategies for Balancing O₂, NO, and CO₂

Breathwork techniques can optimise the relationship between these gases, enhancing energy, relaxation, and performance.

1. Slow, Controlled Breathing for O₂ Efficiency

Breathe slowly and deeply through the diaphragm to increase oxygen absorption and improve cellular function.

This reduces overbreathing, prevents CO₂ loss, and enhances brain oxygenation.

2. Nasal Breathing to Boost NO Production

Always breathe through the nose to stimulate nitric oxide production.

NO helps relax blood vessels, increasing circulation and supporting cardiovascular health.

3. CO₂ Training (Breath Holds) for Oxygen Utilization

Breath-holding exercises help increase CO₂ tolerance, improving oxygen release into tissues.

Slower, controlled breathing enhances nervous system balance and reduces stress sensitivity.

Key Insight: These techniques work together to maintain the optimal balance of O₂, NO, and CO₂, supporting energy, relaxation, and physiological efficiency.

Mastering Breath for Health & Performance

Breathwork is not just about "breathing deeply." To truly master the breath, it is all about training your body to manage oxygen, nitric oxide, and carbon dioxide efficiently.

Takeaway:

• Oxygen powers your cells, but it must be delivered and utilised properly.
• Nitric oxide helps oxygen travel efficiently and is boosted by nasal breathing.
• Carbon dioxide regulates oxygen release and training CO₂ tolerance improves breath control and stress resilience.

By applying these breathwork techniques, you can enhance focus, improve recovery, and optimise performance. All through something as simple as changing how you breathe. Try incorporating slow, nasal breathing and CO₂ training into your routine and see the difference for yourself. 🚀