I have been reading a bit about nosebreathing while running. Like all things related to running there are different opinions as to whether it should or should not be done - whether it has any advantages or not -- but this led me to the subject of hyperventilation. Hyperventilation is a fact of life caused by all kinds of things - panic attacks, heart problems, etc. My understanding of hyperventilation is that it is a bit like positive feedback out of control. A hyperventilating person feels like they are struggling for oxygen and therefore breath at a fast rate - but the fast rate of breathing is actually causing their blood to not accept oxygen from their lungs and cause them to want to breath even faster!! Something like that!!
Apparently we need to expel CO2 from our lungs - BUT we also need CO2 in our blood to cause the blood to accept oxygen from the lungs and transport it to the body muscles - if there is insufficient C02 in the blood, then the blood cannot extract enough oxygen. Insufficient CO2 in the blood is caused by hypervention. Something like that!!
So apparently one of the things we need to do most is to slow down our breathing rate - to allow our blood to pick up Oxygen. Too high of a breathing rate is bad!! I also read of a number of high profile runners ( like Paula Radcliffe) who use nasal strips to open up their nasal airways .
It IS quite difficult to breath ONLY through the nose when running - apparently it is even difficult for many people to do so when not running. - I managed to keep at it today over a full 5K - I have no idea at this time whether it is beneficial or not - but I can say that it stopped me from running too hard on an easy day. I think it will be something that needs to be practiced for some time - just like learning how to run easy and slowly takes time to learn how to do.