If you've ever been on a treadmill and thought, "This feel like torture," you're not far from the truth.

In order to reform idle convicts and combat crime that plagued the Victorian era, Sir William Cubitt invented the “everlasting staircase" in 1818.

It was a large, imposing 24-spoked paddlewheel that could handle as many as 40 convicts endlessly climbing. They were isolated in compartments and forced to climb for hours each day. The purpose was to crush their wills with the monotony and severity of hard labor. But they only wound up irreparably damaging the health of convicts.

One prisoner said about the treadwheel, “I have worked for months on the wheel. I was quite well on coming in. I have now a great pain in the back part of my legs, my loins, and my left side. I get weaker every day. I can hardly stand upright. I know not how I shall be able to do a day’s work. I have nothing to depend upon but my labor.”

Luckily, the use of treadwheels was abolished in Britain by the Prisons Act of 1898. So the next time you finish a grueling workout — be thankful you have the freedom to stop when you’re tired.

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