You can stand for long periods of time without issues, but can only be upside down for a short period of time before you get major head rush.
In: Physics
Your body is eveolved for you being upright at a given amount of gravity, your blood vessels your heart are shaped in a way that facilitates a certain way of circulation.
That circlation includes fighting gravity in your arms and legs.
If you are upside down your body don’t have to fight gravity, rather it helps flow, so the blood rushes.
Like if you have a backpack for a long time and you take it off and feel lighter.
—
This is similar to you raising your arm above your head for a long time. your body is not prepared to pump blood that hight so the blood rushes out.
Latest Answers