I have a question. How long can a person hang upside down before all the blood rushes to the head causing negative side effects? Are there any ways to escape the side effects?

I'm not a doctor, but I think blood pressure to the head at 1G won't give you much more than a headache. And for that there's always acetaminophine or asprin or motrin or ibuprofin. Or drink a caffeinated beverage after you let your feet have a turn with gravity.
Just make sure you haven't been drinking beer all day in the hot sun before trying a stunt like that . . . you should be okay.

***Don't take my word alone on this***
-Kevin.

P.s. Any physically stressful bouts on the body have some form of physiological damage or other. But that's not gonna keep me from riding roller coasters!

The heart is only designed to pump as high as your head, and muscles in your legs assist the return flow up as the heart pumps blood down your leg. (which is why your hand goes numb if you raise your hand above your heart) Once upside down, your heart will not pump blood to your toes and the blood in your brain will not naturally flow out of it and the heart pumps blood in. The effect on you head and limbs will be different for all people.

A friend of mine was lifted 100 feet by crane
it took about ten minutes to get up there as the crane driver hadn't listened to instructions (and hanging at the end of a rope is not a position to yell new instructions) held there for 10 minutes (longer than the escape) and then another 20 minutes to get down again.

He said he couldn't walk for about an hour afterward and the pain as the blood flowed back was great (a severe pins and needles feeling) Try it in the privacy of your own home BUT with a friend to watch over you and get you down if you black out.

Ian

So I'm assuming that it will be extremely harmful if done like, let's say an hour? Let's say if while hanging upside down, I bend at the waist up, so I'm in a v position for like a few seconds or a minute every once in a while, will it help at all?

I'm curious as to why you would want to hang upside down for an hour...

haha, As am I. Also, I'm guessing you could rig up something to keep you tied up but verticle. Say a foot loop at the base of your feet, you could stand on and something holding you nice and close to the rope. You could then wiggle out of that when you needed to and hang upside down. That fall/transition could even look dramatic!

~Spiff

P.S. I'm a rock climber and we spend a lot of time harnessed in and verticle. That's why I thought of this. Here is how I'm looking into doing an upside down escape...

Put on a rock climbing harness and tie in as any rock climber does. This will leave you hanging up-right, BUT if you intentionally wrap your legs around the upper part of the rope you COULD flip yourself upside down and hold yourself there. The harness will still hold, but make sure you crank down on the straps beforehand.

I'm one of those guys that likes to push the envelope, and like endurace challenges...(always wanted to be a bat... lol)

Some challenge being the bat!
You oughta try being the pinata.