Prior to starting their bout in the ring – the “dohyo” made of sand and clay – both sumo wrestlers, or “rikishi”, go through ancient ceremonial preparations. They clap their hands to “awaken the gods”, they toss salt into the ring for its purification, and they stamp their feet to “crush all that's evil”. Dressed only in tightly wound silken loincloths, they then crouch and prepare for the opening charge – both hands are out in front of them, knuckles down on the ground. A bout may last anywhere from a few seconds to several minutes. Whatever the duration, the athletes combine power and technique to force their opponents out of the ring or force them to the ground – with any part of the body other than the soles.