I used to run. Not daily, but at least a couple times a week, and it kept my endurance up. However, my knees are not what they used to be and running on pavement seems to aggrevate them.
So, I am looking into other options, which include running on dirt trails (there are good trails about 5 miles away that I could hit before work), or bicycling (25 mile rides with about 2000 feet of climbing, or longer rides with less climbing; lots of good routes around here). I usually only ride on weekends.
So, my question for all you martial artists is this: what do you do for conditioning and endurance training? What have you found to be most effective and least damaging to your aging joints?
Thanks,
-brian