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Kretschmer’s personality theory
Ernst Kretschmer
...theory that certain mental disorders were more common among people of specific physical types. Kretschmer posited three chief constitutional groups: the tall, thin asthenic type, the more muscular athletic type, and the rotund pyknic type. He suggested that the lanky asthenics, and to a lesser degree the athletic types, were more prone to schizophrenia, while the pyknic types were more likely...
Personality: Morphological (body type) theories
...psychiatrist Ernst Kretschmer. In his book Physique and Character, first published in 1921, he wrote that among his patients a frail, rather weak (asthenic) body build as well as a muscular (athletic) physique were frequently characteristic of schizophrenic patients, while a short, rotund (pyknic) build was often found among manic-depressive patients. Kretschmer extended his findings and...