[Joemoplata]

Running can be bad on the knees, lower back, ankles, shins...yes, all this is true. A lot of this has to do with form and posture, surface, and footwear. But the most critical factor for prolonged wear and tear is frequency and duration. Running everyday for 45 minutes is going to cause you some problems most likely later in life. And for martial arts training, jogging (running in an aerobic state) is not that useful anyway. You should be doing HIIT type of training, intervals of high intensity for shorter periods of time. So you should be sprinting, then walking, then sprinting, then walking for like 20-25 minutes. This will get you better results and have less impact on your joints and you don't need to do it everyday.

As for equipment, the treadmills today are NOT a hard surface, they have cushioning mechnisms in them that absorb impact and would be far better than running on the street (but about as good as a good track). Elliptical machines are zero impact when used correctly and as a result are easier on the joints but not as "taxing" usually on the body overall (it's very hard to simulate full sprinting on an elliptical machine).

And to qualify myself, I worked in a gym for a while and was studying for my PT certification.