manual treadmill?

Question
Nick
I had to curtail my running to to an injury in my knee, which may be becoming arthritic. I can still walk fine but the running action is not so good.
I recently tried a manual treadmill. Until then I thought they were for old ladies recuperating from hip surgery, but I got a great workout. I started sweating quicker than I would from a run, and I could feel a pull in my lower back and abs-probably from the motion and incline. Only drawback was having to hang on to the bar.
I dont understand why these things arent more popular.
Your comments?

Answer
Yea, treadmills are good and bad. Often, treadmills can be great for recovery, but also the footing and placement, which on a treadmill, can be 'tough' and hard on the knees, depending how fast you go. I recently hooked up with this brand, Alter G treadmills, not sure if they are in your area, but definitely worth a look if you have time to http://www.alter-g.com/functional-rehabilitation --

They are great treadmills, and if you can find one by your place of residence, you'll see some amazing results, worth a try being your condition.

Treadmills just don't get the same love natural running does. Like myself, I prefer the outside,and trail running, which can be softer on the joints, and worth a shot if you do have any outside trails by you.

good luck!