Called the "penal" or "prison" "treadmill," or "treadwheel," it is invented to force hard labor on incarcerated people. The intent is to force suffering and sweat as a form of penance. Invented in England, the treadmill comes to U.S. prisons a few short years later, eventually to be discontinued within a generation.

In the early 1900s, the design will be picked up again and marketed as a training machine. It is now the top-selling piece of exercise equipment in the United States.