What Martial Art Should I Learn First?

With each person I train, I begin with developing the boxer within him (or her); then I work from there to help him add other systems, concepts, and techniques.
For younger people—elementary or middle school age—I recommend they take advantage of the wrestling opportunities available to them at school (if they're offered [see Note 1]). I'm very grateful for my wrestling experiences as a young boy in elementary school and junior high (see Note 2) and in a local wrestling club. By the time I began training in the striking arts as a teenager, I'd already acquired years of wrestling experience, which can be difficult to acquire later in life. My wrestling background was very helpful during my years in amateur MMA.
In a nutshell, if you're older, begin with some boxing training; if you're younger, pursue wrestling.
Another thing to ask yourself is this: What is my ultimate purpose in training? Is it mostly for self-defense and life preservation? Or, am I more interested in the combat sports side of things? Or, am I just interested in learning how to move better? more gracefully? more fluidly? Personally, I train for all the above, but that's just me. When I was younger, the self-defense and combat sport sides took center stage. When I was in my thirties, it was life preservation. Now that I'm in my fifties, training in moving well and learning how to better take care of myself (in and out of the cage and on and off the street) are my most dominant motivations.
Train hard, train well. I wish you the best!
Daver
Notes:
I understand that, in some school districts, wrestling is no longer being taught or offered in elementary physical education classes. I think that's tragic. If your child's school doesn't teach wrestling, look for a local wrestling club in your area.
In my school district, not only was wrestling taught in elementary school, but it was offered in PE class all the way through the 8th grade. In high school, you could wrestle JV or Varsity. I'm very grateful for the instruction I received from my school coaches: (1) Mr. Hike, Former PE Teacher (and Secret Service Officer [Ret.]), Cardinal Forest Elementary School, West Springfield, VA; and (2) Mr. Epperly, Wrestling Coach and PE Teacher (Ret.), Robinson Secondary School, Fairfax, VA.
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