Hmm. 5-10yrs fewer in a nation with long life expectancy is pretty impressive to me, really. The obvious one I used to assume was super bad news is the weight issue, with belly fat tending to be particularly terrible for nearby organs. But apparently with sumotori, it's surprisingly not commonly a major issue due to their training methods and cardiovascular health. IIRC the fat tends to float on top of a dense layer of muscle, unlike ye olde coach potato physique.

Btw, I would guess that head slaps in sumo aren't quite as bad as they might seem, due to them being somewhat of an incidental thing not meant so much to cause damage, but to disorganize an opponent for the purposes of bettering one's position. Compare that for example to the slap-fighting leagues, in which one person has to stand in position while the opponent gets to wind up and deliver the equivalent of a perfect, badass hook shot. I mean, holy shoot, you can be boxing and fighting MMA, struggling for many rounds to get off a shot like that, and yet in slap-fighting, it seems like that's more of an 'every shot,' thing. oO

But yeah, no real surprises about the knee issues. That sucks.