Your guide to deciphering your body type. If your eyes glazed over in health class when your teacher started talking “somatotypes,” we’re here to refresh your memory.

Your muscle and fat distribution throughout your body frame determines your somatotype, which is also referred to as your body type.
There are three of these general physiques: ectomorphs, mesomorphs and endomorphs.

QUIZ: What’s Your Body Type?

History of Somatotypes
The somatotype theory dates back to the 1940s, when psychologist Dr. William Sheldon derived the names ectomorph, mesomorph and endomorph from the layers of embryo tissue (ecto-, meso- and endoderm) that develop into parts of the body. In his original theory, Dr. Sheldon drew correlations between body type and temperament, which (no surprise here) he could never prove.

For example, Dr. Sheldon claimed that ectomorphs (who have the tendency to be skinny) are artistic and introverted, while endomorphs (who have more fat on their frame) are tolerant and more extroverted. While it’s true that mesomorphs have a more athletic build, this doesn’t mean they’re more energetic and aggressive, as Dr. Sheldon proposed.


Ectomorphs have a delicate frame without much extra fat. Their limbs are long, and their muscles, lean. They tend to be slender.

Health Implication: A high metabolism means ectomorphs are hungry frequently. Choosing nutritional foods to satisfy this urge is the key to keeping healthy. Ectomorphs could also afford to bulk up more muscle.

Celebrity Examples: “Twiggy” actresses Keira Knightley and Courtney Cox, Paris Hilton and you guessed it—60s model icon, Twiggy herself.

Best Exercise: Walking lunges or squats help build muscle. It tones the legs, and like we said—ectomorphs could bulk up a bit!