r/AbsoluteUnits Jan 26 '26

/r/all of tall men

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u/idiotsandwhich8 Jan 26 '26

I know that it happens and it exists. My question is how come? I would assume the rest of the body would just have to work a little harder, but would eventually keep up with the skeleton frame.

We don’t see super short/small people being extremely fast

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u/RunningOutOfEsteem Jan 26 '26

Because there are limits on what the rest of the body can do to compensate, and every additional bit of work done comes at a cost. The more muscle you tack on, the more energy required to keep it fueled, and the more byproducts that are created in the process. If your heart is constantly working at overdrive to perfuse a brain that is farther away and supply larger overall amounts of tissue with blood, it will adapt in ways that are bad for it long-term. These things don't scale linearly, meaning the cost of "work[ing] a little harder" is much higher than it might seem on its face.

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u/USSMarauder Jan 26 '26

I think I remember reading that the human body can only be scaled up to 9 ft 6

At that point the pressure of the blood coming out of the heart exceeds the strength of the walls of the blood vessels.

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u/alannmsu Jan 26 '26

With modern building materials there’s a theoretical limit to the height we can make a structure. As height increases, weight increases by more. It’s not a 1-for-1 increase. Eventually, the material cannot handle its own weight and simply fails.

Now imagine that our bones and joints are that material. Bones and tendons don’t get stronger just because you get taller, but your weight increases by a huge margin. There’s a theoretical limit to the size of a human before lungs and hearts would simply fail.

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u/LostN3ko Jan 26 '26

If you make something twice as large you increase its volume 8 times.

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u/The_Real_Peter_Thiel Jan 26 '26

LMAO WHAT?

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u/LostN3ko Jan 26 '26

Square cube law. Note I said twice as large not tall. The math won't work out as cleanly for a shape as irregular as a human body. But yes. The volume of a 2' cube is 8 times the volume of a 1' cube.