Hi,
Does anyone here incorporate boxing into your fitness routine?

I'm having some knee issues so have had to back off on eliptical, treadmill and bikes. There is a boxing bag at the gym I go to and today I decided to try it. I LOVED it! There is an older guy there that gave me a few pointers to get me started but I'd like to learn more about developing a routine.

Does anyone have any sources to point me to or any advice? (I did a google but didn't find much for starting routines for women to do with a bag.)