after judo class back in the late 90,s in new jersey my judo instructor(a japanese gentleman named yanizuka,we just called him yanni for short)held sumo practice,he had us take off our gi,s,then take our belts and make a circle about 20 ft by 20 ft.i remember they put me in the circle with emanual yarbrough,hes a 700lb sumo guy from rahway new jersey,i charged at him and he threw me with one arm out of the circle and i hit my head on a bench 25ft of the matoff the mat.to be honest i never realized how much technique it took to do sumo,i always thought it was just 2 big fat guys smacking bellies ramming into eachother,lol.but as i started staying for the classes i realized how great your balance and explosive power has to be,i never really got any good at it though,lol