King Rama VII (r. 1925–35) pushed for codified rules for muay, and they were put into place. Thailand's first boxing ring was built in 1921 at Suan Kularp. Referees were introduced and rounds were now timed by kick. Fighters at the Lumpinee Kickboxing Stadium began wearing modern gloves, as well as hard groin protectors, during training and in boxing matches against foreigners. Traditional rope-binding (Kaad Chuek) made the hands a hardened, dangerous striking tool. The use of knots in the rope over the knuckles made the strikes more abrasive and damaging for the opponent while protecting the hands of the fighter. This rope-binding was still used in fights between Thais but after the occurrence of a death in the ring, it was decided that fighters should wear gloves and cotton coverlets over the feet and ankles. It was also around this time that the term muay Thai became commonly used while the older form of the style came to be known as muay boran, which is now performed primarily as an exhibition art form.