The machine is designed to work out not just the legs and hips but also the arms and shoulders. The only part of the body it leaves untouched is the brain, that restless organ.
Outdoor walks provide a moving display of images on which to dwell: familiar houses comfort, treed paths shelter, new vistas enliven.
But the elliptical walker has, if she wishes, a TV with streaming shows and old movies and whatever else she can find for distraction. She has a library of music and books to plug into on her phone. She has, in short, the world at her fingertips. And so she walks, and walks, and walks ... going nowhere but quite content.