Answer: The Treadmill

In modern use, the term treadmill refers to an exercise device in which the user walks on a belt which continuously cycles around the machine such that the user can walk or run for as long as they desire to do so. But why call it a “treadmill?” Why not a name that actually describes what it does like “treadbelt” or “tread walker?” Where does the mill bit come from?

It turns out the origins of the treadmill are both archaic, a bit torturous, and actually related to milling. Back in 1818, an English engineer (Sir William Cubitt) created a device that looked like a very long paddle wheel he called the “tread-wheel” which he intended for use as a tool to reform strong willed and defiant convicts in the British penal system.

The prisoners were forced to walk up the paddle wheel, in a method of movement that is more like a modern stair climber than a treadmill, and much like water turns the paddle wheel of a mill to crush grain, the energy of the prisoners was harnessed and used to either pump water, grind grain, or power ventilators in mines. Eventually, thanks to the widespread use of the devices to grind grain, the name tread-wheel was dropped in favor of tread-mill.

The treadmill was widely credited with subduing problematic behaviors in inmates and New York prison guard (the treadmill migrated well outside of England by the end of the 1820s) James Hardie wrote that it was the treadmill’s “monotonous steadiness, and not its severity, which constitutes its terror.”

Nearly two centuries later prisoners no longer run on treadmills to grind grain, but the general population at large has certainly taken (thanks to the rise of the aerobics movement in the late 20th century) to the activity with a passion.