fȳst-gebēat, n.n: a blow with the fist. (“fuhst-yeh-beh-aht”)
I found this image on Medievalists.net along with a paper discussing whether the art of boxing vanished during the Middle Ages. It’s surprisingly difficult to find medieval images of unarmed people fighting with their hands only. This one (Codex Wallerstein) is from the late Middle Ages, c. 1470.