The non-motorized elliptical-looking apparatus with individual foot pads allows you to accurately replicate a real running motion with no impact. It has greater stride length/range of motion than an elliptical and less impact than a treadmill.
The most realistic running motion of any non-treadmill I’ve tried. While you can make a variety of movements, from an elliptical-like oval glide and an up-and-down stair step, the Zero lets you flow into a real running gait. That is due to a design that mimics the leg by placing pivot points at the knee and hips, and it includes a foot platform that can flex like an ankle.
That allows you to flick your heel back and almost kick your own butt. Combined with the large potential stride length (I was hitting 50 inches at 6:48 miles, double the length of the best ellipticals), it feels very real. My heart rate, as expected, was a little less than on land by about 10 beats per minute, which actually encouraged me to go at a faster pace (which is displayed on the monitor along with elapsed time and stride length).
Having a problematic right knee, the complete lack of impact was a dream for me. I could see runners using this to do a significant chunk (20% to 30%) of their training, thereby saving wear and tear on the joints without losing any conditioning. In that sense, it’s like water running but more technique-specific. Plugless, self-powered, it is dead silent. It will be available in Busybody and other fitness stores Aug. 1.