Mezomorf

Mezomorf, or mesomorph, is a term used in the somatotype framework to describe a body type typically characterized by a muscular, well-proportioned physique with a favorable baseline for strength and athletic performance. In this model, mezomorphs are often thought to have a higher proportion of muscle mass and lower body fat compared to other types.

Common physical traits associated with mezomorf bodies include broad shoulders, a narrow waist, a naturally strong and sturdy frame, and the ability to gain muscle relatively easily. Individuals described as mezomorphs are frequently perceived as having a fast or efficient response to resistance training and a tendency toward a lean, athletic appearance with relatively low-to-moderate body fat.

The concept originates from William Sheldon’s somatotype theory developed in the mid-20th century, which also defined ectomorphs and endomorphs. Although the framework has influenced fitness and bodybuilding communities, it is viewed by many scientists as an oversimplified and imprecise model of human physique. Contemporary research emphasizes body composition, genetics, training history, nutrition, and overall health rather than rigid typologies.

In practice, the mezomorf label is most commonly used as a general guide in fitness contexts to tailor training and nutrition, suggesting a potential favorable response to resistance training. However, the classification should be approached with caution, recognizing that individuals often display mixed traits and that outcomes depend on lifestyle factors, not just body type.