I have bad knees but I decided to attend several classes before making my decision. As Josh mentioned, lots of hand techniques. Excellent instruction and a great group of people. I have been going now for 20 months. Best shape I have been in years. I highly recommend you come observe a few classes.
The style often focuses more on hand techniques than kicking, and the stances are higher and not as difficult on the knees as other styles of kung fu or karate. That being said it is worth trying it out to see how you feel. This school has a very relaxed and engaged instructor and offers a trial period that let's you try it out and see if you like it before making the financial investment.
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