Donnie Porko is correct. I'll further explain that I disagree with the wording of you question since "MMA" and "kickboxing" are martial SPORTS that are catered toward one-on-one combat in a controlled environment that consists of separate rounds. Martial arts if taught for applicable combat might not have a calisthenics regimen in their regular curriculum.
For instance, I have had private students where lessons were one-on-one and lasted from 30 minutes to 1 hour. My time for which I was compensated was to teach techniques and concepts, which I explained to students and potential students. I always emphasized the importance of physical fitness, but I implore students to do this on their own (along with practicing their martial arts on their own outside of lessons); why pay me my rate to watch you do sit-ups, push-ups, join you for a run, etc. when you can do that on your own for free? In context, it was a waste of time and money.