Ecorche
An écorché (French pronunciation: [ekɔʁʃe]) is a figure drawn, painted, or sculpted showing the muscles of the body without skin, normally as a figure study for a work, or as an exercise in training. Renaissance architect and theorist, Leon Battista Alberti recommended that when painters intend to depict a nude, they should first arrange the muscles and bones, then depict the overlying skin.
Some of the first well known studies of this kind were performed by Leonardo da Vinci. His studies included dissecting the cadaver and creating detailed drawings of the subject. However, there are some accounts of this same practice taking place as far back as ancient Greece, though the specifics are not known.
The term écorché, meaning literally "flayed", came into usage via the French Academies (such as the École des Beaux Arts) in the 19th century. This form of study still continues at traditional schools throughout the world including the New York Academy of Art, the Art Students League of New York, the Grand Central Academy of Art in New York City, the Pennsylvania Academy of the Fine Arts in Philadelphia, and the Academy of Art University in San Francisco.
During the Renaissance in Italy, around the 1450 to 1600, the rebirth of classical Greek and Roman characteristics in art led to the studies of the human anatomy. The practice of dissecting the human body was banned for many centuries due to the belief that body and soul were inseparable. It wasn’t until the election of Pope Boniface VIII that the practice of dissection was once again allowed for observation. Many painters and artists documented and even performed the dissections themselves by taking careful observations of the human body. Among them were Leonardo da Vinci and Andreas Vesalius, two of the most influential artists in anatomical illustrations. Leonardo da Vinci, in particular, was very detailed in his studies that he was known as the “artist-anatomist” for the creation of a new science and the creative depiction to anatomy. Leonardo’s anatomical studies contributed to artistic exploration of the movement of the muscles, joints and bones. His goal was to analyze and understand the instruments behind the postures and gestures in the human body.
...
Wikipedia