Treadmills Were Invented as Punishment

Long before it became a staple of modern gyms, the treadmill was an instrument of grueling prison labor. In early 19th-century England, prisons were filled with inmates who had little to do, a situation that reformer and engineer Sir William Cubitt sought to remedy in 1818. He designed a massive, rotating cylinder with exterior steps, creating an endless staircase. Prisoners would be forced to climb for up to ten hours a day, a monotonous and physically devastating task designed to break their will and serve as a powerful deterrent to crime.

The sheer scale of the labor was immense, with convicts often ascending the equivalent of 7,000 vertical feet in a single shift. This wasn't merely pointless toil; the energy generated by the prisoners' constant stepping was often harnessed for productive means. The turning of the great (Review) wheel could be used to pump water or, most commonly, to mill grain. It was this direct application of treading for milling that gave the device its literal name: the tread-mill. The practice was eventually abolished near the turn of the 20th century after being condemned as excessively cruel, leaving behind a fascinatingly dark origin for today's popular exercise machine.