Arc Trainer?
 

I just joined a new gym, and they have a numnber of Cybex Arc Trainers. I'm not familiar with these at all, and am wondering if anyone who uses them can comment on how they differ vs. an elliptical, as well as how they might be on bad knees?
Cindy

I much prefer the arc trainer to the elliptical. I find it smoother and less lurchy, if that makes sense. I occasionally have knee pain from running, but I have never had any knee issues with the arc trainer. Hope that helps!

I feel like the arc trainer works more muscle groups. Maybe that's just psychological, but that's just how it feels to me. Also, I burn more calories (unless the machine is wrong, which is very possible). Anyway, I do have a problem w/ my right knee, but never felt any issues w/ the arc trainer. :)