I-Sumo (isiJapane: H, Hepburn: sumō, [sɯmoː], ikhanyisiwe. "Ukushayana") kuyindlela yokulwa okuqhudelana ngokugcwele lapho i-rikishi (wrestler) izama ukuphoqa isitha sayo ukuphuma eringini eliyisiyingi (dohyō) noma ekuthinteni umhlabathi nganoma yisiphi isitho somzimba ngaphandle kwamathe ezinyawo zakhe (imvamisa ngokumjikijela, ngokumsunduza noma ngokumcindezela phansi). I-sumo yobuchwepheshe ayikhiphi abesifazane emncintiswaneni nasemikhosini. Imidwebo yodonga lwangaphambili ikhombisa ukuthi i-sumo yavela emdansweni wesiko lezolimo owenziwa ngomthandazo wesivuno esihle. Ukukhulunywa kokuqala kwe-sumo kungatholakala embhalweni wesandla waseKojiki osukela ku-712, ochaza ukuthi ukutholwa kweziqhingi zaseJapan kwathathwa kanjani kumdlalo we-wrestling phakathi kwekami owaziwa ngokuthi yiTakemikazuchi neTakeminakata. UTakemikazuchi wayengunkulunkulu wezulu lokuduma, inkemba, nokunqoba, okwenziwe ngegazi elachithwa lapho u-Izanagi ebulala idimoni lomlilo uKagu-tsuchi. UTakeminakata wayengunkulunkulu wamanzi, umoya, ezolimo nokuzingela, kanye nozalo olude lukankulunkulu wesiphepho uSusanoo. Ngenkathi uTakemikazuchi efuna ukunqoba umhlaba wase-Izumo, uTakeminakata wamphonsela inselelo yokulwa ngezandla. Kuma-melee abo, uTakemikazuchi wabamba ingalo kaTakeminakata wayicoboshisa "njengomhlanga," wehlula uTakeminakata wafuna ne-Izumo.