The treadmill was invented as a punishment device for prisoners. In 1818, British engineer Sir William Cubitt designed what he called the “everlasting staircase” to keep convicts occupied with grueling, monotonous labor. The machine we now associate with New Year’s resolutions and morning cardio spent its first century as one of the most dreaded fixtures in the English prison system.
Treadwheels Existed Long Before Prisons
Cubitt didn’t invent the concept of humans walking to power a machine. Treadwheels date back to ancient Rome, where they were used to operate cranes on construction sites. A Roman crane powered by a treadwheel could lift 6,000 kilograms, double what a hand-cranked winch could manage, with only half the crew. A detailed carving on the Haterii tombstone from the late first century CE shows one of these devices in action.
After falling out of use with the collapse of the Western Roman Empire, treadwheel cranes reappeared in medieval Europe around 1225. They became essential equipment at harbors, mines, and cathedral construction sites across France, England, and Germany. These were productive machines, though. Workers climbed them to move heavy loads. Cubitt’s innovation was stripping away the useful output and turning the act of climbing into the entire point.
Cubitt’s “Everlasting Staircase”
Cubitt designed his treadmill as a wide hollow cylinder made of wooden steps built around an iron frame. Some models were large enough to handle 40 prisoners at once, all walking side by side on the rotating steps. The concept was simple: inmates climbed continuously, like walking up a staircase that never ended.
In some prisons, the treadmill was connected to a grain mill or water pump, giving the labor at least a thin justification of productivity. In others, it powered nothing at all. Prisoners called this “grinding the wind,” stepping endlessly with no result beyond exhaustion. The machine became enormously popular in Victorian England, where inmates were forced onto treadmills for up to 10 hours a day. According to Harvard University researchers, this was the equivalent of climbing a 12,000-foot mountain in a single session.
The purpose was explicitly punitive. Prison authorities believed that hard, monotonous physical labor would deter future crime and impose discipline. The treadmill required minimal supervision, which made it efficient for wardens. It spread rapidly through British prisons and eventually to facilities in the United States, including Connecticut’s Old New-Gate Prison.
From Prison Tool to Medical Device
The penal treadmill was gradually phased out in the late 1800s as attitudes toward prison reform shifted. For decades, the concept sat dormant. Then in 1952, Wayne Quinton and Dr. Robert Bruce at the University of Washington built a motorized treadmill for an entirely different reason: diagnosing heart and lung conditions. Their device let doctors monitor a patient’s cardiovascular response while the patient walked at controlled speeds and inclines. This became the foundation of the cardiac stress test, a procedure still used in hospitals today.
For the next 15 years, treadmills remained clinical tools found only in medical facilities. They were expensive, bulky, and not designed for anyone exercising by choice.
How a Book Created the Home Treadmill
The jump from hospital equipment to home fitness machine happened because of one book. In 1968, Dr. Kenneth Cooper published “Aerobics,” which made a data-driven case that regular cardiovascular exercise could dramatically improve health. The book became a bestseller and helped ignite the jogging boom of the 1970s, a cultural shift fueled by figures like Olympic marathoner Frank Shorter, running coach Bill Bowerman, and even President Jimmy Carter, who ran recreationally.
A mechanical engineer named William Staub read Cooper’s book and noticed a gap in the market. There were no affordable treadmills available for home use. So he built one himself. Staub developed the PaceMaster 600 in the late 1960s, the first consumer treadmill designed for a living room rather than a lab. The machine was basic by today’s standards (his son Gerald designed the on-off switch), but it gave ordinary people a way to follow Cooper’s aerobic exercise recommendations without needing a track, a gym membership, or good weather.
The timing was perfect. Cooper’s research had convinced millions of Americans that running could extend their lives, and Staub gave them a machine to do it indoors. The PaceMaster 600 laid the groundwork for an industry that now fills basements and commercial gyms worldwide.
Two Centuries, Three Purposes
The treadmill’s history is really three separate inventions sharing a mechanical concept. Cubitt built a punishment device in 1818. Quinton and Bruce built a diagnostic tool in 1952. Staub built a fitness machine in the late 1960s. Each version repurposed the same basic idea, a moving surface that forces you to keep walking, for a completely different goal. The fact that millions of people now voluntarily climb onto a machine originally designed to break prisoners’ spirits is one of the stranger twists in the history of exercise equipment.