I would think all the martial arts training would be great for coil building, concentration and breathing making it a rather Zen experience
There is some truth to that. Martial arts can bring out the best or worst in anyone. It depends on how it is taught.
I was in notorious Chung Mo Quan. It's all funny now but was a reality check when I was in it. People from the outside either laughed at it or feared it. The people in it either were a great fit and wanted to be trained to the nth degree as weapons or looking for a way out. They attracted nothing but the finest because everyone was freaked out to even go in the dojo. One of the Head Regional Instructors attended my high school in Illinois and he won state for his weight division in greco roman wrestling at least 5 times that I know of.
The founder, John C Kim, who had schools in many states was charged with tax fraud. Schools in Illinois, where I attended, were charged with extortion and threatened to harm police officers for telling them that the Governor of the State of Illinois had revoked their license to conduct business within the entire state. I rcvd a call from my mom while at college that there was a standoff being broadcast on TV and several schools were shut down with a few getting arrested. They were extremely tough, bad cookies.
They would sign people up for programs and expected you to be there and did not care that you, your family, or job had other plans. It basically was a cult. You had to run everything by them before you made any major decisions. If you missed, they called. If you missed twice, they sent a car load of high ranking instructors to bring you to school. I know an entire family that joined the US Navy to get away from them. They sold their home, and the mother, son and daughter all enlisted. They were not a McDojo, they were serious nutcakes!
They had class and special lessons from around 4AM to 12PM ever hour, every day of the week. Depending on what program you signed up for, you were expected to be there 1, 2, 3, 4 hours or the entire day depending upon your rank. 2 hour sessions were called double sessions, and almost everyone did them at high intensity.
The instructors lived dorm style in homes purchased by the school. Students could work off or pay for school by working at the instructors residence.
I joined the Marine Corps and was booted for a heart murmur. They were ticked, but couldn't do anything. They kept calling the house to make sure I was "gone" ... hahaha. But as I said, the Marine Corps booted me so one day they caught up with me and made me submit a DRs statement that I could no longer work out with them. They wanted proof!
That isn't the only rogue school out there. I know of others.