Read some article recently, could be from Dr. Rotella . An interesting theory of why the YIPS happen.
Rooted back to the stone age when human didn’t have sophisticated weapons to hunt and to defend, so when in danger and the adrenaline start pumping, the blood will flow to the core and the big muscle, to aid the running to escape danger.
This has been passed on down to modern human beings, so when we got excited or experiencing extreme fear, the smaller muscle would be lack of blood flow. That included the hands and the fingers, hence also why our stomach “butterfly” . Because the blood flow out of the fingers/hands and into the big muscle and core.
Recognizing this theory, rubbing and shacking hands and fingers will offer temporary relief from the YIPS syndrome, supposedly.
I had never tried this method since I don’t have the issue. However, definitely experienced the feeling of hollowness when I was in stress for a period of time. It happened several times when I was in play off in other sports regional arena. Don’t know what to do, maybe a hand stand ?