Yeah. It's basically just kicking and punching in the air. I read the same book (really good, wasn't it?), and I tried it. It's really good for just loosening up, letting yourself flow (which is good for me, because I tend to think too much about what I'm doing instead of just letting it flow through me), and provides a moderately good cardio exercise (depending on how good of shape you're in, and how fast you shadow box). Hope this helped!
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"If life gives you lemons, you blow those lemons to bits with your laser cannon!" - Brak