Do you ever find yourself holding your breath unintentionally when you’re focusing on work? Or days when you’re constantly yawning and sighing, even though you slept well?

These phenomena are related to the acid-base balance in your blood and consequently, the state of your central nervous system.

Sighing and yawning inflate your lungs maximally while stretching your diaphragm and intercostal muscles to prevent the collapse of the alveoli that might be caused by the increased PaCO2. 

(Notice that dogs and cats also sigh!)

This largely unconscious, homeostatic mechanism expels the excess gas (carbon dioxide) from your lungs and allows your body to relax and relieve dyspnea.

Our exercise aims to replicate that, while also preparing you for more advanced techniques. While CO2 is very important to deliver oxygen to the tissues, when you aren’t prepared to handle high concentrations, it can cause issues.

Here’s the research on the topic:

1. A sigh of relief or a sigh of expected relief
2. CO2-evoked release of PGE2 modulates sighs and inspiration as demonstrated in brainstem organotypic culture
3. Sigh maneuver protects healthy lungs during mechanical ventilation in adult Wistar rats
4. Sigh rate during emotional transitions: More evidence for a sigh of relief
5. Yawning and airway physiology: a scoping review and novel hypothesis

More interesting videos:

*You’ll hear three different views in these three videos. We suggest you practice the exercises the way we’ve described them in the book but feel free to explore the topic more in-depth.