My knees have always been a little weak and as I aged running became harder and harder on my joints. I still really enjoy cardio and Qi has these incredible glider machines that mimick the motion of inline skating or cross country skiing. The machine doesn't hurt my knees at all and I still get to work up a sweat with some powerful cardio that's the kind of workout I enjoy.
Pros: Great variety of machines and eqipment
more