I dont do Kyokushin but i know that my style has roots in it. We do 20 2 minute rounds of full contact bare knuckle sparring with the only breaks being changing partners. on the second day of shodan grading, that morning you are buggred anyway because of the previouse day that took 5 hours to complete (inkluding lots of throws). for nidan we have to do 30 2 minute rounds bare knuckle full contact. i dont know if this is any indicator, but thats how it goes for us.