What is the science behind the ectomorph, mesomorph and endomorph

Body Types: Mesomorphs. Ectomorphs, & Endomorphs Explained - NASM

Body Types: Mesomorphs. Ectomorphs, & Endomorphs Explained - NASM

360fit: From Mesomorphs to Ectomorphs - Body type and weight loss

Train For Your Body Type: Endomorph, Mesomorph And Ectomorph

Is Chris Evans an ectomorph, mesomorph, or endomorph? - Quora

Mesomorph Body Type Characteristics & Diet Explained

Ectomorph: Body Type Characteristics & Diet Plans - Tua Saúde

I'm short with a lot of belly fat and low muscle mass. I have narrow shoulders, a relatively wide pelvis, short limbs, thin arms, relatively thick legs, and small wrists and ankles.

Are the terms 'ectomorph', 'mesomorph' and 'endomorph' accepted and used by the scientific community? - Quora

What does it mean to be a pure endomorph or a pure mesomorph? Is it possible to fit these descriptions exactly, and if so, what would someone who does look like?

Is Chris Evans an ectomorph, mesomorph, or endomorph? - Quora