Make sure you haven't eaten anything yet and take a seat.
This is the video you never knew you needed.
From Gizmodo:
Everything is cooler in slow motion, and when the Slow Mo Guys point their high-speed cameras at a pair of massive sumo wrestlers with a combined weight of over 450kg, you can actually see the shockwaves rippling through their bodies as the two near-immovable competitors collide in the ring.