It's important to note that hanging upside down for a prolonged period is extremely dangerous. It can lead to:
* Brain injury: Blood flow to the brain is disrupted when hanging upside down for extended periods.
* Eye problems: Increased pressure on the eyes can cause vision impairment.
* Muscle cramps and pain: The unusual position puts immense strain on the muscles.
* Organ damage: Organs can be compressed or suffer from lack of blood flow.
Therefore, attempting such a stunt is highly discouraged.
If you're interested in learning more about David Blaine's feats and the dangers of endurance stunts, I recommend researching reputable sources like medical journals or reputable online publications.