Edit for more clarification.
Could someone provide a more physics, structure of cell, sharing of weight over cells, based explanation?
In: 25
They’re not just cells, they’re skin, muscle, and bone – meaning the cells have formed complex structures that can do more than their individual components.
If you think about it that way, if your skin muscles and bones couldn’t support your body weight, we’d never have been able to evolve in the first place.
If you could somehow focus your entire body weight onto the area of a single cell, it would presumably crush it, but that’s not the situation.
The skeleton forms a frame which supports the majority load of your body weight (very much like the metal frame of a building) to distribute it throughout your body. Muscles support your Skeleton to help keep the frame in place and again help distribute the load.
Skin cells on feet do get crushed, but only in a sense. This is why you develop rougher and harder skin on the bottom of them, because the body forms extra keratin in these cells to make them more resistant to damage.
Edit .. Ooops I forgot muscles!
Same reason your tires dont get squished by your car’s weight. They do, but they are designed and built to handle it, and are perfectly suites to operate under the preasure.
They do, and then they bounce back. This is why sitting/lying down lets your feet relax after you remove the weight from them.
They’re ‘built’ to withstand it. The structures of your bones, tendons, muscles, etc. are working to support your weight.
What do you expect?
The bodies response to pressure is more skin, or callouses. Corns are basically what happens when skin gets “squished” in the foot in the wrong direction from poor footwear.
So short version, skin gets thicker to compensate.
@ op : I can’t say much from a biology perspective but here the physics:
Your body is truly that: a body. If a body is at rest, all forces acting on it are equal.
Gravity exerts a force on your body proportional to your mass.
Let’s say you weight 150 lbs. gravity is exerting 150 lbs of force on your body. This force is acting downward. We need a force to balance out this one acting downward.
This force comes from the ground. This is called a normal force. It is acting upwards and is equal to 150 lbs. with 150 lbs upwards and 150 lbs downwards, you remain at rest. Where does this force from the ground act? At your feet. Really, across the surface of your feet.
So gravity is pulling your body whole body down. Your skeletal structure takes on these forces and transfers the forces to the only place where we have one to balance it out : the ground.
Now think of your skin between the bones of your feet and the ground.
This skin is in a state of compression. (Good search term). When thinking of compressive stresses, the normal force is sort of a given so we do not need to consider the top layer (or face) of your skin in-between the bottom of your foot bones and the ground. That’s the skin right up against the bottom of your foot bones.
Let’s say both of the bottoms of your feet have a total surface area of 30 square inches.
Compressive stress = force / area
Stress = 150 lbs / 30 square inches
Stress = 5 pounds per square inch.
So the bottoms of your feet are really only feeling 5 pounds per square inch of compressive stress.
Edit minor spelling
Fun fact: sometimes they do. Google “mechanical hemolytic anemia” for how you can literally crush your own red blood cells! It happened to someone I used to run with— she was a beast and maybe kind of overdid it.
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