A mesomorph is one of the three primary body types in the somatotype classification system, which was developed by William Sheldon in the 1940s. Mesomorphs are characterized by a muscular and well-proportioned physique, with broad shoulders and a narrow waist. They typically have a higher percentage of muscle mass and can gain strength and size more easily than other body types. Individuals with a mesomorphic body type often excel in physical activities and sports due to their natural athleticism. They usually have a medium frame and can maintain a balanced weight with relative ease. This body type is often associated with a fast metabolism, allowing for efficient energy use and recovery.