Edit for more clarification.
Could someone provide a more physics, structure of cell, sharing of weight over cells, based explanation?
In: 25
@ 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
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