Today I ran my mile, just as I promised, even though it would have been so easy not to do it. I figured since I will not get a chance to run while I'm in San Diego, Friday-Sunday, I might as well make the most of my week here before I go. (I can't run in San Diego while I'm visiting friends because I can't bring my tanks on the plane.)
Today I brought my pulse oximeter with me to find out why I felt so ill during the second half of my run yesterday. Turns out the first minute or two my oxygen saturation stays pretty stable. It drops from 100% on 5 liters to 95%. That is totally NORMAL! But then it continues to drop the more and more I push myself. So even though I'm still on 5 liters of O2 my sats decrease to 90% and they stay there. That is really interesting because I'm sucking on a whole lot of oxygen! 5LPM is a massive dose and it's the highest output my tank has.
I may have to re-think/re-organize my plan to continue to run like this. Obviously, running 1 mile on 90% is not going to kill me today, but I may be doing damage to my heart in the long run. The good news is my HR is pretty stead in the 160's which is pretty normal for me, even during my jog. That probably has a lot to do with the oxygen not dipping below 90%. I know from experience once I get into the 80's my HR also jumps into the 180's.
Today's time was better than yesterday at 12 minutes 29 seconds!
I have 4 more days to experiment with this mile a day project. Stay tuned!