力士 (rikishi) are professional wrestlers in the traditional Japanese sport of sumo. They compete in a circular ring called a dohyo, where their goal is to force their opponent out of the ring or to make any part of their body other than the soles of their feet touch the ground. Rikishi come from various backgrounds and undergo rigorous training in stables known as heya. They wear a distinctive garment called a mawashi, which is a belt made of thick fabric. The sport is steeped in tradition and rituals, reflecting Japan's rich cultural heritage.