Im not sure, I would assume its about on par with MMA fighters but because it inst regulated in Japan they dont have to disclose it.
EDIT: Search for the K-1 events from Vegas cause they would have to disclose to the athletic commision...
"If you get hit and it hurts hit him back you not knocked out yet."-Joe Doerksen
The Toxic Terrors (FFL)
Georges St. Pierre*Sarra McMann*Pat Curran*Patricio Freire*Uriah Hall
NP FFL Team Toxic Challenge
Fabricio Werdum*Gilbert Melendez*Rick Hawn*John Dodson*Urijah Faber