Article by Emanuel Giordano

Sai are metallic trident truncheons, and are part of the typical weapons of Okinawan Kobudo. The method of fighting with this weapon is called Sai-jutsu, and involves the simultaneous use of two or three Sai, to be used against an opponent armed with longer weapons. The Sai is built to strike with both ends, to defend using the three points, and to hook the opponent's weapons with the two shorter points. In some ways, its use recalls the trident used by the gladiator retiarius (the man with the net), which in addition to hitting, was also used to trap the opponent's sword, usually a gladiator belonging to the secutor (pursuer) and murmillo (moray eel) categories .
The Sai, however, in addition to being a short weapon, are also used in hojo undo for strengthening the upper part of the body and, in particular, the wrists and forearms. In the numerous Karate books published in mainland Japan they are included among the body training tools, and the captions leave no room for misunderstandings: the Sai, in Japanese Karate, were both a hojo undo tool and a weapon. They appear in 1938 in Karate-do Taikan (Nakasone Genwa) and in Karate-do Nyumon (Mabuni Kenwa), and then reappear in several tables of drawings included in Japanese Karate books and manuals, published in the following decades. The illustrated table accompanying this article is taken from Karate-do Nyumon by Ichikawa Kojiro (1955), a book that proposes many drawings and contents of the aforementioned Karate-do Taikan. To it I have attached two photos that portray Funakoshi Gichin sensei, since in one the Sai appear used as a weapon to oppose the Bo, while in the other they appear together with other tools typical of the hojo undo, in this case geta (presumably tetsu-geta), a chi-ishi and a makiwara. This could suggest that Funakoshi sensei introduced the use of the Sai both as a weapon and as a training tool.
The use of Sai as a training tool in Karate is often related to the practice of Karate kata. The Sai, in fact, are held by the karateka during the execution of the kata of their school. This type of training is present both in Okinawan Karate, as my teacher Maeshiro Morinobu sensei showed me, and in Japanese Karate (mostly in Goju-ryu), as my friend and colleague Matteo Brianti sensei showed me.
  • "Shorin-ryu Karate: kata 2" (here)
  • "Shorin-ryu Karate: kata" (here)
  • "Shorin-ryu Karate: The legacy of the bodyguards of the king of Okinawa" (here)
  • "The legend of the masters of Okinawan Karate: Biographies, curiosities and mysteries"  (here)