Training and ritual
Shiko is the familiar movement in which a wrestler shifts weight onto one leg, raises the other leg, and stamps it down before repeating on the opposite side.
In training, shiko develops balance, hip mobility, leg strength, and control of the wrestler's center of gravity. It is deliberately repeated and should not be confused with a decorative dance step.
Shiko also has a ceremonial role. Wrestlers stamp near the dohyo before a bout, and the Yokozuna performs large, deliberate stomps during the Yokozuna dohyo-iri. In the ritual explanation given by the Japan Sumo Association, the stamps drive evil from the ring. The crowd may time a call of “yoisho” to the Yokozuna's foot coming down.