Somatotype is a theory proposed in the 1940s by the American
psychologist
A psychologist is a professional who practices psychology and studies mental states, perceptual, cognitive, emotional, and social processes and behavior. Their work often involves the experimentation, observation, and explanation, interpretatio ...
William Herbert Sheldon
William Herbert Sheldon, Jr. (November 19, 1898 – September 17, 1977) was an American psychologist, numismatist, and eugenicist. He created the field of somatotype and constitutional psychology that correlate body types with temperament, illus ...
to categorize the human physique according to the relative contribution of three fundamental elements which he termed ''somatotypes'', classified by him as ''ectomorphic'', ''mesomorphic'', and ''endomorphic''. He created these terms borrowing from the three
germ layer
A germ layer is a primary layer of cell (biology), cells that forms during embryonic development. The three germ layers in vertebrates are particularly pronounced; however, all eumetazoans (animals that are sister taxa to the sponges) produce tw ...
s of
embryonic development
In developmental biology, animal embryonic development, also known as animal embryogenesis, is the developmental stage of an animal embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm, sperm cell (spermat ...
: The
endoderm
Endoderm is the innermost of the three primary germ layers in the very early embryo. The other two layers are the ectoderm (outside layer) and mesoderm (middle layer). Cells migrating inward along the archenteron form the inner layer of the gastr ...
(which develops into the
digestive tract
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...
), the
mesoderm
The mesoderm is the middle layer of the three germ layers that develops during gastrulation in the very early development of the embryo of most animals. The outer layer is the ectoderm, and the inner layer is the endoderm.Langman's Medical ...
(which becomes
muscle
Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contra ...
,
heart
The heart is a muscular Organ (biology), organ found in humans and other animals. This organ pumps blood through the blood vessels. The heart and blood vessels together make the circulatory system. The pumped blood carries oxygen and nutrie ...
, and
blood vessel
Blood vessels are the tubular structures of a circulatory system that transport blood throughout many Animal, animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the Tissue (biology), tissues of a Body (bi ...
s) and the
ectoderm
The ectoderm is one of the three primary germ layers formed in early embryonic development. It is the outermost layer, and is superficial to the mesoderm (the middle layer) and endoderm (the innermost layer). It emerges and originates from the o ...
(which forms the skin and
nervous system
In biology, the nervous system is the complex system, highly complex part of an animal that coordinates its behavior, actions and sense, sensory information by transmitting action potential, signals to and from different parts of its body. Th ...
).
Later variations of these categories, developed by his original research assistant Barbara Heath, and later by Lindsay Carter and Rob Rempel, are used by academics today.
Constitutional psychology is a theory developed by Sheldon in the 1940s, which attempted to associate his somatotype classifications with human
temperament
In psychology, temperament broadly refers to consistent individual differences in behavior that are biologically based and are relatively independent of learning, system of values and attitudes.
Some researchers point to association of tempera ...
types.
The foundation of these ideas originated with
Francis Galton
Sir Francis Galton (; 16 February 1822 – 17 January 1911) was an English polymath and the originator of eugenics during the Victorian era; his ideas later became the basis of behavioural genetics.
Galton produced over 340 papers and b ...
and
eugenics
Eugenics is a set of largely discredited beliefs and practices that aim to improve the genetic quality of a human population. Historically, eugenicists have attempted to alter the frequency of various human phenotypes by inhibiting the fer ...
.
Sheldon and
Earnest Hooton were seen as leaders of a
school of thought
A school of thought, or intellectual tradition, is the perspective of a group of people who share common characteristics of opinion or outlook of a philosophy, discipline, belief, social movement, economics, cultural movement, or art movement.
...
, popular in
anthropology
Anthropology is the scientific study of humanity, concerned with human behavior, human biology, cultures, society, societies, and linguistics, in both the present and past, including archaic humans. Social anthropology studies patterns of behav ...
at the time, which held that the size and shape of a person's body indicated
intelligence
Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. It can be described as t ...
, moral worth and future achievement.
In his 1954 book, ''Atlas of Men'', Sheldon categorized all possible body types according to a scale ranging from 1 to 7 for each of the three ''somatotypes'', where the pure ''endomorph'' is 7–1–1, the pure ''mesomorph'' 1–7–1 and the pure ''ectomorph'' scores 1–1–7.
From type number, an individual's mental characteristics could supposedly be predicted.
In a late version of a
pseudoscientific
Pseudoscience consists of statements, beliefs, or practices that claim to be both scientific and factual but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable cl ...
thread within
criminology
Criminology (from Latin , 'accusation', and Ancient Greek , ''-logia'', from λόγος ''logos'', 'word, reason') is the interdisciplinary study of crime and deviant behaviour. Criminology is a multidisciplinary field in both the behaviou ...
in which criminality is claimed to be an innate characteristic that can be recognized through particular
physiognomic markers (as in
Cesare Lombroso
Cesare Lombroso ( , ; ; born Ezechia Marco Lombroso; 6 November 1835 – 19 October 1909) was an Italian eugenicist, criminologist, phrenologist, physician, and founder of the Italian school of criminology. He is considered the founder of m ...
's theory of
phrenology
Phrenology is a pseudoscience that involves the measurement of bumps on the skull to predict mental traits. It is based on the concept that the Human brain, brain is the organ of the mind, and that certain brain areas have localized, specific ...
), Sheldon contended that criminals tended to be 'mesomorphic'.
The system of somatotyping is still in use in the field of
physical education
Physical education is an academic subject taught in schools worldwide, encompassing Primary education, primary, Secondary education, secondary, and sometimes tertiary education. It is often referred to as Phys. Ed. or PE, and in the United Stat ...
.
The three types

Sheldon's "somatotypes" and their associated physical and psychological traits were characterized as follows:
:
Stereotyping
There may be some evidence that different physiques carry
cultural stereotypes, as some cultures are more prone to certain physiques. According to one study endomorphs are likely to be perceived as slow, sloppy, and lazy. Mesomorphs, in contrast, are typically stereotyped as popular and hardworking, whereas ectomorphs are often viewed as intelligent yet fearful.
Heath–Carter formula
Sheldon's physical taxonomy is still in use, particularly the Heath–Carter variant of the methodology. This formulaic approach utilises an individual's weight (kg), height (cm), upper arm circumference (cm), maximal calf circumference (cm), femur breadth (cm), humerus breadth (cm), triceps skinfold (mm), subscapular skinfold (mm), supraspinal skinfold (mm), and medial calf skinfold (mm), and remains popular in anthropometric research, according to Rempel: "with modifications by Parnell in the late 1950s, and by Heath and Carter in the mid 1960s somatotype has continued to be the best single qualifier of total body shape".
This variant utilizes the following series of equations to assess a subject's traits against each of the three somatotypes, each assessed on a seven-point scale, with 0 indicating no correlation and 7 indicating a very strong correlation:
where:
*''Ectomorphy '': Calculate the subject's
Ponderal Index:
** If
,
** If
,
** If
,
This numerical approach has gone on to be incorporated in the current
sports science
Sports science is a discipline that studies how the healthy human body works during exercise, and how sports and physical activity promote health and performance from cellular to whole body perspectives. The study of sports science traditionally i ...
and
physical education
Physical education is an academic subject taught in schools worldwide, encompassing Primary education, primary, Secondary education, secondary, and sometimes tertiary education. It is often referred to as Phys. Ed. or PE, and in the United Stat ...
curriculums of numerous institutions, ranging from the UK's secondary level GCSE curriculums (14- to 16-year-olds), the Indian UPSC Civil Service exams, to MSc programs worldwide, and has been utilized in numerous academic papers, including:
* Rowing athletes
* Tennis athletes
* Judo athletes
* Volleyball athletes
* Gymnasts
* Soccer athletes
* Triathletes
*
Han people
* Persons with
diabetes
Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough of the hormone insulin, or the cells of th ...
*
Taekwondo
Taekwondo (; ; ) is a Korean martial art and combat sport involving primarily kicking techniques and punching. "Taekwondo" can be translated as ''tae'' ("strike with foot"), ''kwon'' ("strike with hand"), and ''do'' ("the art or way"). In ad ...
athletes
*Persons with eating disorders
*
Dragon boat
A dragon boat is a human-powered watercraft originating from the Pearl River Delta region of China's southern Guangdong Province. These were made of teak, but in other parts of China different kinds of wood are used. It is one of a family of t ...
participants
Criticism
"The Varieties of Human Physique" by Sheldon et al (1940) classified body types into three categories using
data processes that would not be accepted by researchers today. Sheldon's ideas that body type was an indicator of temperament, moral character or potential – while popular in an atmosphere accepting of the theories of
eugenics
Eugenics is a set of largely discredited beliefs and practices that aim to improve the genetic quality of a human population. Historically, eugenicists have attempted to alter the frequency of various human phenotypes by inhibiting the fer ...
– were later disputed.
A key criticism of Sheldon's constitutional theory is that it was not a theory at all but a general assumption of continuity between structure and behavior and a set of descriptive concepts to measure physique and behavior in a scaled manner.
His use of thousands of
photographs of naked Ivy League undergraduates, obtained without explicit consent from a pre-existing program evaluating student posture, has been strongly criticized.
While popular in the 1950s,
Sheldon's claims have since been dismissed as "
quackery
Quackery, often synonymous with health fraud, is the promotion of fraudulent or Ignorance, ignorant medicine, medical practices. A quack is a "fraudulent or ignorant pretender to medical skill" or "a person who pretends, professionally or public ...
".
Barbara Honeyman Heath, who was Sheldon's main assistant in compiling ''Atlas of Men'', accused him of falsifying the data he used in writing the book.
See also
*
Biological anthropology
Biological anthropology, also known as physical anthropology, is a natural science discipline concerned with the biological and behavioral aspects of human beings, their extinct hominin ancestors, and related non-human primates, particularly fro ...
*
Biomechanics
Biomechanics is the study of the structure, function and motion of the mechanical aspects of biological systems, at any level from whole organisms to Organ (anatomy), organs, Cell (biology), cells and cell organelles, using the methods of mechani ...
*
Body mass index
Body mass index (BMI) is a value derived from the mass (Mass versus weight, weight) and height of a person. The BMI is defined as the human body weight, body mass divided by the square (algebra), square of the human height, body height, and is ...
*
Body shape
Human body shape is a complex phenomenon with sophisticated detail and function. The general shape or figure of a person is defined mainly by the molding of skeletal structures, as well as the distribution of muscles and adipose tissue, fat. Ske ...
*
Eugenics in the United States
Eugenics, the set of beliefs and practices which aims at improving the Genetics, genetic quality of the human population, played a significant role in the history and culture of the United States from the late 19th century into the mid-20th c ...
*
Female body shape
*
Kinanthropometry
*
Neurobiological effects of physical exercise
*
Physiognomy
Physiognomy () or face reading is the practice of assessing a person's character or personality from their outer appearance—especially the face. The term can also refer to the general appearance of a person, object, or terrain without referenc ...
*
Physiology
Physiology (; ) is the science, scientific study of function (biology), functions and mechanism (biology), mechanisms in a life, living system. As a branches of science, subdiscipline of biology, physiology focuses on how organisms, organ syst ...
*
Somatology
References
Sources
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Further reading
*
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External links
*
{{DEFAULTSORT:Somatotype And Constitutional Psychology
Anthropometry
Body shape
Biological anthropology
Criminology
Pseudoscience
Psychological theories
Racism