Expert: Walter Hintz - 2/1/2009

Question
Hi Walter, I am trying to find out what the effects of earth's gravity would have on a human body if that person was a lot larger, say fifty feet tall? I realise that under earth conditions they would not be able to reach that size, but for the sake of discussion, let's just say they have and are suddenly subjected to earth's gravity. Is there a size at which we become unable to hold ourselves upright for instance? What specifically would happen to our bodies and how it functions? Any help or direction would be appreciated.
Sincerely
Mark

Answer
 Hi Mark
Isaac Newton said that every body in the universe is attracted to every other body with a force directly proportional to the mass and inversely proportional to the distance between them. The larger the person the greater the gravitational force upon him.  Now weight is the measure of mass in a gravitational field.
How big do you have to be before you cannot stand up.  The worlds tallest man was Robert Wadlow at 8'11" and 490 lbs.  He had to wear leg braces but could stand.  The worlds heaviest man weighed 1225 pounds and could not walk. It seems likely that at 700 or 800 pounds would be the limit for standing upright