THREE MACHINES IN ONEThe Cybex Arc Trainer offers broad incline & resistance ranges which means it is really 3 machines in one. At the lower incline levels, the "glide” is a cross country skier. In the mid-range levels, the motion is a "stride” (like an elliptical except with proper positioning). At the high levels, the "climb” of a stepper or climber. Glide, Stride, & Climb. &... lots of programs also make the Arc Trainer fun to use. EASY ON THE JOINTSNo more "elliptical knees”. Unlike other cross trainers on the market the patented Arc pattern of motion allows the hip & knee to move synchronously while the foot stays under the knee reducing joint pains & providing a more comfortable workout.