Non-combat benefits of MA training
As I think about it, there are also some benefits we haven't really discussed, but that are still real.
1) Learning how to fall and roll. In my case, this helped me with downhill skiing, of all things. In aikido and aiki-jutsu, falling and rolling are viewed as pro-active, not reactive. One doesn't wait until one's joints are hyper-extended, one feels the lock coming on and throws oneself into a roll or fall to protect the joint. Perceiving falling as pro-active makes falling much less scary. As far as skiing went, I was able to rapidly move up to diamond and double diamond trails, once I realized that if I grew uncomfortable with speed or with an upcoming, ultra-tight turn, I could just toss my body uphill from my skis into a side fall, stop, and regroup.
In a training partner's case, extensive practice in rolling came in handy when a little old lady pulled out in front of his chopper. He flew over her hood, hit the ground in a shoulder roll, and came up with just some scuffed leather and no injuries beyond bruises.
2) Improved balance. A lot of people see a slow form, like in Tai Chi, and think, "What value is there in moving so slowly?" Try it sometime. If you can change directions and shift balance in super-slow-mo, you'll find it very easy to do it in normal speed. Slow speeds reveal poor foot placement and balance, and also can show where effort is being wasted. Slow speed drills therefore increase efficiency and economy of motion, and improve balance. Note that improved balance, posture, and footwork can really improve shooting skills... but who in this forum would care about that?
3) (Potentially) improved overall fitness. Where I'm currently training, we work out when it's hot and humid. We start out with 50 knuckle pushups, 50 crunches, a bunch of planks, running in place, jumping jacks as standard. Then we'll add things. Yesterday, one of the warm-ups involved several sets of one partner lying on his back, the other assuming a sort of push-up position above and slightly forward of him; guy on the ground grab the other guy's gi, and using a pull-up form, pulls his body up and forward across the mat; up guy advances position, and down guy does another pull-up. Cross the room several times this way, changing positions each leg. Then, we picked up various target pads, and did a round robin of ten kicks or punches on each pad, from either hand and foot. Again, this was the warmup. We did a few other things in there, too, like military style low crawls and jujutsu style shrimping. Everybody was sweating pretty hard before we started on any technique training.
4) Not to be overlooked: it's fun. And, by the way, OP, of the four of us who trained yesterday, three of us are 43, all class of '86. Not sure about the other guy, but think he's late 30's. And the three 43 year olds also hit the shooting range together with some frequency. Some of my longest lasting friendships have been with people from dojos where I've trained over the years.
Now, there are potential downsides. Overconfidence has been alluded to by several. Of course, overconfidence isn't a risk when it comes to CCW... Also, time and effort are required, and those are often precious. Money is usually required, too - although the organizations where I train usually only charge enough to pay the rent and replace broken training equipment. In such organizations, instructors don't get paid, or else they get paid a token amount.
And, of course, there's injury. Over the years, I've broken my left big toe (guy went for a takedown, slipped, and his knee fell square on my toe), dislocated both thumbs (thankfully not at the same time), had more cuts inside my mouth than I care to think about, sprained my neck, suffered chronic wrist pain (from nikkyo locks) for a couple years (those finally went away last year).
In training accidents, I've dislocated one partner's shoulder (he resisted taking a fall or roll until way too late in the throw - he said that himself) and just yesterday hyper-extended another's elbow with an arm bar (he was trying to show me I was out of position on his arm by resisting; meanwhile, I was shifting position because I could tell I was a bit off; we both felt it when one of his ligaments shifted and rolled around the elbow a bit; I let off as soon as I felt that - I felt bad about it, he looked at it as having been his own fault).
I won't count the number of times I've hit somebody a bit harder than anticipated, or they've done the same to me. Get two bodies in motion (or more, for that matter) and things happen.
Oddly enough, it's not normally the new guys who get hurt. It's normally the more experienced guys, who tend to push limits a bit more. Or, it's the more experienced guys, trying to protect the new guys - trying to catch a guy who's falling wrong can do bad things to backs, shoulders, etc.
Still, the benefits outweigh the negatives, at least in my view.