Entering the Ring and Starting a Bout
Sumo bouts are conducted in a ring with a hard dirt surface. On top of a square platform, there is a circular ring 4.55 meters (about 15 feet) in diameter. The bouts take place inside the ring.
After their shiko-na (official wrestling names) are called, the wrestlers climb into the ring, perform shiko (alternately raising and stamping their feet on the ground forcefully, with their hands on their knees) and throw salt into the ring to purify it. They then match their opponent's movements as they lower their waist, open their knees to the side, and go into their shikiri (taking their mark and facing their opponent in a posture that will allow them to move forward at any moment). The wrestlers match their breaths with their opponent, and once both of them place fists on the ground, the bout begins. While the bout is underway, the referee shouts "Nokotta!" (Remaining!) while the wrestlers are grappling with each other and "Hakkiyoi!" (Come on!) when the wrestlers are not moving.
How the Winner is Determined and Kimarite (Winning Techniques)
When one of the wrestlers is forced out of the ring or touches the ground with any part of his body other than his feet, the referee raises the fan in his hand to declare the winner. The kimarite (winning technique) where the winner forces his opponent out of the ring by getting in close and lifting him out by his mawashi is called yorikiri, while bringing him down is known as yoritaoshi. When a wrestler uses his weight to push his opponent backwards down to the ground, this is called abisetaoshi.
Oshidashi involves one wrestler pushing the other underneath his arms or in the chest without grappling, and forcing him out of the ring. Whether it happens inside or outside of the ring, oshitaoshi is a move by which a wrestler pushes his opponent to the ground. When a wrestler uses one arm to grab his opponent underneath the arm or on his side and forces him down at an angle, this is called tsukiotoshi.
A wrestler grabbing his opponent's mawashi from outside the opponent's arms and throwing him to the ground is known as uwatenage, and when he does the same thing while dragging his opponent, it is called uwatedashinage. When a wrestler grabs his opponent inside his arms, this is called shitatenage. The number of winning techniques has increased and decreased over the years, but at present there are 82.
In addition, there are 8 moves that are prohibited. These include striking an opponent with a clenched fist; poking an opponent in a vulnerable area, such as the eyes and the pit of the stomach; and kicking an opponent in the chest or the stomach. Wrestlers who use prohibited moves lose by hansoku (disqualification).