Body Shape — Somatotypes (Endomorph / Mesomorph / Ectomorph)

There have been many attempts by biological scientists over the last 100 years to place humans into various body types (Bloomfield et al., 1992; Komi, 1992). Sheldon (1954) used a sample of 46,000 males to identify three basic builds:

• Endomorph — the obese/fat-dominant build.
• Mesomorph — the muscular type.
• Ectomorph — characterized by a high degree of linearity (thin, long-limbed).

Each of these three components is rated on a seven-point scale, indicating the degree of dominance of that characteristic. A somatotype is described with three numbers, given in order — endomorphy, mesomorphy, ectomorphy — e.g. a rating of 6-1-1 or 7-2-1 indicates endomorphic dominance (classified as endomorph); a rating of 2-7-1 indicates mesomorphic dominance (mesomorph); a rating of 1-2-7 indicates ectomorphic dominance (ectomorph). Most people, however, demonstrate a combination of two physique types rather than a single dominance — pure single-type somatotypes are the exception, not the rule.

Body shape plays an important role in the selection of individuals for competitive sport, and sports-science literature has considerable information on which somatotypes suit not just particular sports but specific events or positions within them. Because many factors make up a champion athlete's physical profile, there is no single perfect body shape for a given sport or event — but it is still useful to know which shapes tend to suit which sports.

Expert guidance on diet and intensive exercise can help an athlete partially modify their somatotype within the limits of their genetic make-up:

• If an individual is within one standard deviation of the mean for their sport's typical group, little modification is needed.
• Athletes outside that range need a special program to help move them closer to the mean of their group.

Somatotype has been shown to be predictable with some accuracy as early as preadolescence. That said, any body type can be developed by proper resistance training and nutrition — genetics set a range, not a fixed outcome.

• Sheldon (1954), sample of 46,000 males: 3 basic builds.
• Endomorph = obese/fat-dominant; Mesomorph = muscular; Ectomorph = high linearity.
• Each component rated 1-7; a somatotype = three numbers (endo-meso-ecto order).
• Example: 6-1-1/7-2-1 = endomorph; 2-7-1 = mesomorph; 1-2-7 = ectomorph.
• Most people are a combination of two types, not a single pure dominance.
• Body shape affects suitability for specific sports/events/positions, but no single shape is "correct" for any one sport.
• Within 1 SD of a group's mean → little modification needed; outside it → a targeted program to move closer to the mean.
• Somatotype is predictable with some accuracy from preadolescence, but any body type is trainable via proper resistance training + nutrition.

• individuality — somatotype is one axis of the individual variation that principle already covers generally.
• sports-associated-resistance-training — the companion topic on this source page (goal-based programs by sport).
• fat-deposition-patterns — a related but distinct individual-variation topic (where fat is stored, vs. what someone's overall build tends toward).
• exercise-selection — where the "move an athlete's shape toward their sport's mean" idea would translate into actual program choices.
• body-shape-frame-types — a distinct, non-scientific classification (torso proportion/silhouette, not overall build) that this module's build-based system is sometimes confused with.