I think I'm like most dumbass Americans in conceptualising Sumo as "just a bunch of fat guys bouncing off each other until one a them falls out the ring, haha."
But in reality, yeah, those guys are actually thunderous powerhouses of muscle and technique, from what I understand. I've read here and there about what makes for a sumōtori, and it's... gosh, almost like living upon a different planet. Almost.