Figure 4. Terracotta Panathenaic prize amphora ca. 500 B.C. Atributed to Kleophrades Painter. The picture is derived from the site of the Metropolitan Museum of Art: https://www.metmuseum.org/art/collection/search/130009546. Depicting an umpire (hellanodike) watching the athlete executing the kick known as gastrizein or pternizein. The opponent was able grab the foot and is about to react with another technique. The image has been analyzed by OpenPose and is viewed using Matplotlib.

From

Estimating Athletes’ Centre of Mass as Presented on Ancient Greek Pottery Depictions

Andreas G. Bourantanis, Nikitas N. Nomikos, Constantinos C. Trompoukis, Weijie W. Wang

American Journal of Sports Science and Medicine. 2022, 10(1), 12-16 doi:10.12691/ajssm-10-1-3