Samdive,
Let us know if you find out anything. I took the DAN course about 8 months ago and purchased an O2 kit from them. I got to use it on myself after I blacked out during static one day. I had left the kit at home so it was a couple of hours before I was able to do it. I was suffering pretty bad fatigue and having trouble staying focused starting about 1 hour after the black out. The O2 help me feel better, but not by as much as I thought it would. It made me alert enough I could watch TV for 1½ hours, but by 9 PM my alertness was gone and I crawled (literately!) to bed.
My guess is that the body tissue gets mostly fully oxygenated just from normal breathing after a black out. It would be interesting to know what the difference would have been if I had taken it right away. The next day my O2%’s were a little lower than normal when I did my dry statics with a pulse/ox, but my heart rate was also low and I was very relaxed so the results were just as good as normal.
I also used the O2 while having the flu. It seemed to help in that application as well. It would be great to know more on how to use it for freediving, since the DAN course is geared for scuba diving and nitrogen flushing. My instructor thought he knew a lot about freediving, but as you can imagine, he knew almost nothing.
don
