So yeah, this exercise is like 4 or 5 different exercises/meditations all-in-one hence why some believe it’s the ultimate yoga exercise.
So my first caveat would be to try it by itself, as described, first.
Like anything (and a ongoing theme of my many posts) give yourself a “baseline” before adding to it.
Now, I’ve done this exercise for many many years and, just as the author said, it CAN knock you on your ass…literally.
It’s THAT powerful.
So, I’ll be giving other fields, techniques that “stack” well with this later on.
So, saying that, the breathing described above, IS a pranayama onto itself.
Having said all that, any pranayama breathing technique will work.
Just make it as intense as possible whether slow or fast to create that “static electricity” effect with your Solar plexus.