The Three Body Types (Somatotypes)
The concept of somatotypes — ectomorph, mesomorph, and endomorph — was introduced by psychologist William Sheldon in the 1940s. While not a perfect science, these body type categories provide useful guidance for customising nutrition and training approaches.
Body Type Characteristics
| Type | Build | Metabolism | Common Challenge |
|---|---|---|---|
| Ectomorph | Slim, narrow, long limbs | Very fast — burns calories easily | Hard to gain weight or muscle |
| Mesomorph | Athletic, broad shoulders | Moderate, efficient | Can gain fat if diet is poor |
| Endomorph | Stockier, fuller figure | Slower, efficient storage | Prone to fat gain, needs active management |
Important Caveats
Most people are a blend of two body types. Genetics are not destiny — an endomorph who trains consistently and eats well can achieve a leaner physique than a sedentary ectomorph. Body type guides your starting strategy, not your ceiling.
Scientific note: Body somatotype science has evolved significantly since Sheldon. Modern nutrition and training science focuses more on individual response to stimuli (training, diet, sleep) than fixed body type categories.