Mesomorphs, Ectomorphs, and Endomorphs: A Historical Moment in Psychology.

The terms mesomorph, ectomorph, and endomorph are commonly found in bodybuilding forums or fashion advice blogs.  Did you know that these same terms were once a means for a psychiatrist to quickly conclude personality characteristics depending on body type?  I want to briefly discuss what mesomorphs, ectomorphs, and endomorphs meant in the history of psychology.

Why did psychiatrists care about a patient’s body type?

If a psychiatrist knows the nature of a patient, they can understand the patient better.  At least that is the reasoning behind understanding the body types and what each type’s characteristics are.  Even more specifically, a psychiatrist wants to understand what satisfies an individual.  What is it that they desire most?  When they understand the answers to these questions, they can help people overcome unhappiness or suffering.

Developing fetus and body type

Did you know that while we grow as a fetus, different areas develop at different times? Maybe it is your belly that grows first, or maybe your mind or muscles. At one time scientists believed that the area that developed first in a fetus determined what kind of body type would develop.   


Endomorphs are characterized as having a round physique.  They are jolly and love to eat.  Think of a politician with a cigar in his mouth and you have a typical endomorph.  They enjoy eating and getting attention, especially if they are going to a party that is celebrating them.  They have round stomachs, thighs and arms, but little feet and hands.  


Mesomorph’s are muscular, rugged, and broad in build. They have large chests, wide shoulders, flat, firm stomachs, and muscular forearms and thighs.  Typically their skulls are bony, and they have a square jaw.   Career choices would include such jobs as life-guards, construction workers, army members, or athletes.  They have a lot of muscle and like to use the energy made from them.  A mesomorph seeks adventure, competition, and getting the upper hand.


When you imagine an ectomorph, you see thin and long looking individuals.  Even if they are short they have a long look to them.  Ectomorph have thin bones and muscles, a flat stomach, and sloping shoulders.  Their necks and fingers are long and they have a face like a long egg.  Their natural disposition is jumpy and quiet.  Typically they like to keep to themselves.


In the history of psychology, psychiatrists used what they knew about body types and their dispositions to make quick judgments on their patients.  The terms ectomorph, endomorph, and mesomorph have moved away from being diagnostic for psychologists.  But it is interesting to think how the terms have become a part of our society’s vocabulary.  


Berne, Eric. The Mind in Action. New York, Simon and Schuster, 1947. pages 3-32.

Further Reading