When English civil Engineer Sir William Cubitt invented the “treadwheel,” he didn’t have fitness on his mind.
His device was used to reform convicts.
Prisoners were forced to climb the spokes of a large paddle wheel known as the “eternal staircase.” The resulting energy was used to pump water or crush grain (hence, the eventual transition from “treadwheel” to “treadmill”).
One prison guard claimed that it was the treadmill’s “monotonous steadiness, and not its severity, which constitutes its terror.”
The use of treadwheels was abolished in Britain by the Prisons Act of 1898. Years later, when aerobic exercise became popular in the 1960’s, the treadmill resurfaced.