A popular alternative motion cardio unit that offers extreme efficiency and effectiveness backed by exercise science. It’s really three machines in one.At lower incline levels, it glides like a cross-country skier. In the middle, it strides like an elliptical. At higher levels, it’s a climber. The Arc Trainer produces less stress on the knees than walking, and is ideal for general exercisers, those looking for a challenging HIIT workout, and everyone in between.