Apidej Sit-Hirun (September 1941 – April 4, 2013), born Narong Yaenprateep, was a famous muay Thai fighter. Born in Samut Songkhram, Thailand, Sit-Hirun was best known for his powerful kicks. In one fight, he broke both of Sompong Charoenmuang's arms, and forced the fighter to retire. He is considered the hardest kicker in muay Thai history. Apidej simultaneously held no less than seven muay Thai and boxing titles for a period during the 1960s. Thereafter, he was acclaimed as a national hero and Muay Thai Fighter of the Century by HRH King Bhumibol Adulyadej. After his retirement, Apidej taught as an instructor at the Fairtex school outside Bangkok, Thailand alongside modern champions such as Yodsaenklai Fairtex and Kaew Fairtex. He died of lung cancer at the age of 72 on April 4, 2013, at Phramongkutklao Hospital, Bangkok.