Chinese Kenpo for about 8 yrs., boxing, Muay Thai, some grappling and Kali. I mostly train in boxing now, usually on my own. I recently went to a boxing class at a local health club. It wasn't bad, but they didn't stress technique too much. It was mostly for cardio, 3 minute rounds with 30 second rest. I made it through the class, but at age 55, was the oldest person in the class. It almost seemed to be too much for me.