07/20/2026
If you've ever wondered at a deeper level about the benefits of Sanchin breathing here's the information. I learned about it from an old time bodybuilder. Seems they understood somethings back then and I saw how this transferred over to Sanchin and karate as a whole. I researched it to confirm it through AI and here's what I found.
Nasal breathing releases nitric oxide (NO) primarily through production in the paranasal sinuses, which then travels into the lungs and bloodstream, improving blood flow (via vasodilation) and breathing efficiency (via better oxygenation and related effects).
Step-by-Step Process of NO Production and Release Continuous Production in the Sinuses:
Epithelial cells in the paranasal sinuses (especially the maxillary and ethmoid sinuses) constitutively express nitric oxide synthase (NOS) enzymes, particularly an inducible form (iNOS-like). These enzymes convert L-arginine and oxygen into NO gas. Sinus NO concentrations are very high—often thousands of parts per billion (ppb), far exceeding levels in the nasal cavity or lower airways. The sinuses act as a reservoir.
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Release into Nasal Airway:
NO diffuses from the sinuses into the nasal cavity mainly through small openings (ostia), aided by diffusion (dominant) and some convection from airflow. Factors like nasal airflow rate, turbulence, humidity, and even practices like humming (which creates oscillations) enhance this exchange—humming can increase nasal NO output up to 15-fold.1e3b24 During nasal inhalation, this NO mixes with incoming air.
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Inhalation into the Lungs:
Unlike mouth breathing (which largely bypasses this), nasal breathing carries the NO-enriched air down to the lower airways and lungs. This is sometimes described as an "aerocrine" hormone effect—NO produced in the upper airways acts distally in the lungs.
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Entry into Blood and Systemic Effects:
In the lungs, NO diffuses into the bloodstream and tissues. It activates soluble guanylyl cyclase in smooth muscle cells, increasing cyclic GMP (cGMP), which leads to relaxation of vascular smooth muscle.
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How It Improves Blood Flow (Vasodilation)
Pulmonary Vasodilation and V/Q Matching: NO acts as a selective pulmonary vasodilator, relaxing blood vessels in well-ventilated areas of the lungs.
This improves ventilation-perfusion (V/Q) matching—aligning airflow with blood flow for more efficient gas exchange. Studies show nasal breathing redistributes lung blood flow (e.g., ~4% shift, with greater relative increases in under-perfused areas like the apices) and can increase arterial oxygenation (PaO2) while sometimes lowering pulmonary vascular resistance.
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Systemic Benefits: Some NO reaches the systemic circulation, supporting overall vasodilation, blood pressure regulation, and endothelial function. This contributes to better oxygen delivery to tissues, reduced vascular resistance, and cardiovascular benefits. Nasal breathing has been linked to improved flow-mediated dilation (a marker of NO bioavailability).
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How It Improves Breathing Itself
Enhanced Oxygen Uptake: Better V/Q matching means more efficient oxygen transfer from alveoli to blood, raising transcutaneous or arterial oxygen levels (e.g., ~10% higher tcPO2 in some nasal vs. oral breathing studies).
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Bronchodilation and Airway Support: NO helps relax bronchial smooth muscle and supports mucociliary clearance (moving mucus and debris), keeping airways clearer. It also has antimicrobial effects, aiding host defense.
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Overall Respiratory Efficiency: Nasal breathing slows and deepens respiration naturally (due to higher resistance), promotes better CO2 tolerance in some contexts, and avoids the disadvantages of mouth breathing (dryer air, less conditioning, bypassed NO). This leads to improved oxygenation, reduced work of breathing over time, and better recovery. 43d58b Motionspecificrelease
Key Notes:
Mouth breathing skips most of this NO delivery, potentially reducing these benefits.
Factors like slow nasal breathing, humming (e.g., Bhramari pranayama), or breath-holding can amplify NO release.
This is a normal physiological process, with therapeutic implications (e.g., inhaled NO is used medically for certain lung conditions). Individual results vary with sinus health, nasal patency, etc.
This mechanism highlights why nasal breathing is emphasized in practices like yoga, martial arts training (relevant to your karate background), and general health optimization. Consult a doctor for personalized advice, especially with any respiratory or cardiovascular conditions.
