On 1/13/2021 6:03 AM, Peter wrote:
On 1/12/2021 5:04 PM, Clare Snyder wrote:

** I've even noticed that sometimes when wearing a mask my blood oxygen
level is HIGHER than without the mask - possibly becuse when wearing
the mask I tend to breath more "purposefully" - trying to avoid
fogging my glasses? - Don't know - but it puts the lie to masks
reducing the ability to breathe - - -



Clare, sorry to disagree, but your speculation is not borne out by the
facts of respiratory physiology.* I assume that by breathing more
"purposefully" you mean either or both more deeply and/or more rapidly.
*That's called "hyperventilation."* Doing that, you will lower the
carbon dioxide content of your blood but will do nothing at all to
increase the oxygen concentration in your blood.* The only external ways
to increase your blood oxygenation are to either increase the
concentration of oxygen as a fraction of the total composition of the
gas you are breathing, or be exposed to a gas mixture containing an
unchanged percentage of oxygen at a high pressure than is normal at sea
level (1 atmosphere pressure (14.7 pounds per square inch) or to apply
both of those procedures concurrently.* In more technical terms, you
need to raise the partial pressure of oxygen entering your lungs and
those two maneuvers can accomplish that.* The invasive way to increase
oxygen content of your blood would be to increase the concentration of
red blood cells per unit volume of your blood by transfusion- which is
extremely dangerous if your red cell concentration is normal to begin with.

Easily done by pressure breathing. Exhausting against resistance to
increase pressure.