Capitalizt said:
I don't have the $$$ for classes but would like to learn a real fighting style. Is this possible?
No. That's my first reaction. It's not totally correct through, so I'll elaborate on my position.
Unless you have a good background in other martial arts, you have little to build on. You would be making lots of mistakes because of innocent assumptions, and these mistakes may well be avoided entirely by using a teacher. casualbb made a good point on that.
You wouldn't be learning a "real" fighting style even if you could emulate all the forms you ever saw. Again, you'd have to be a natural or be building on a good body of knowledge to be any good.
Still, there is great value in training on your own, and lots of very capable people train on their own.. although most of them either train in their own time to supplement their existing in-class training or already have a background of experience with the same art to work with.
And yet there are people who study exclusively with videos! (Yes, they exist) These are quite dedicated people, some of whom don't have a background in martial arts. It's still possible to improve yourself on your own time. I'd say the biggest help for self-training would be to have a friend train with you. Even in the absence of a teacher, it's very useful to have feedback and motivation from your friend.
Or should I just get a heavy punching back and get used to kicking the crap out of it?
If you're lucky that'll teach you to kick the crap out of a punching bag. If you're not lucky you'll have poor form and will be learning bad habits. Although there is certainly lots of value in training with objects, people are not much like punching bags. For one they don't tend to stand there for you to hit them.
Still, a punching bag would be good for practicing punching properly.. but only if you already knew how. I used to think that knowing how to punch was obvious, but it's really not. e.g. learning boxing isn't about learning to punch a heavybag.
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All that having been said, there's value in picking up a tape or two and trying stuff out. I'd say that general calisthenics would be the one thing you could do very well on your own. Getting in shape is a big deal, and one which you can learn without a teacher if you try hard (and train safe).
However I maintain that you've got little connection to the real thing training on your own.. unless you have a background to build on.