Until I was 10, I was very violent and had a behavior problem.
I served many detentions, suspensions, and was expelled from many schools.
It wasn't that I couldn't fight, it was the attitude to fight, win or lose, and to misbehave.
My parents had tried everything, including a psychiatrist. To which he had told them, that I being the "middle child", I was seeking special attention via my actions. (These words I know form later discussions, many years after, with my parents). I believe he was wrong. I had did bad things not for attention, but because I had liked it. I wanted to "get away" with anything or not get caught. To show my attitude, I told the psychiatrist if he didn't stop seeing me and taking my parents' money, I will say that he was touching me in my privates. Sessions ended after that speech.
At a large family gathering, a reunion that family members were allowed to bring friends, my mother had met and spoke with a woman whom had a "problem child" with the same behavior as mine.
The woman told her that she had enrolled her son in Karate and that his attitude had changed. So my mother spoke with my father (whom had made a discission at the time to send me to a boys' home), about Karate lessons. They could not understand the concept.
Decades later, while taking courses in psychiatry, I had realize why, per monks, would do so. I have written a thesis/article in this.
Anyway, my first Karate school and/or lessons, did not go so well as I was expelled from that one. Bascially, the teacher had no experience with a child such as me and I tested his patience to the brink.
But, I would later attend other martial art schools, due to rekindled desire and changed residencies.
