This is called Shaho hassetsu (Kyudo hassetsu) and was established by the Shaho-seitei-iin (constitution committee of shooting an arrow) of the Nihon Kyudo Federation (predecessor of the All Nippon Kyudo Federation) after the war.
これを射法八節（弓道八節）と言い、戦後に日本弓道連盟（全弓連の前身）の射法制定委員により制定された。