The treadmill is undoubtedly one of the greatest and most convenient exercise machines ever invented. 

It allows you to jog in the comforts of your living room or in fact any confined space big enough to fit a treadmill. 

Source: runnersworld

But did you know that treadmills weren't invented with an exercise machine in mind? The history of the treadmill is pretty interesting and you won't believe how it got its name.

The concept came from the Romans who, around the 1st century AD, came up with a device that was termed as a 'tread wheel'. It was used to lift huge weights. People would step onto the wheel and walk within it, something similar to what the Ferris wheel guy does at melas. 

The wheel was of course much larger in diameter (big enough to hold people inside) and with the help of the crane attached to it, it would heave objects that were twice the weight using just half the manpower.  

Source: wikipedia

Then in the 1800s, horses were made to run on belts that would help generate power because natural wind or water, being inconsistent, did not always work. From a wheel, we moved on to a belt-like structure. 

Interestingly enough, some historians claim that this also contributed to the origin of the term 'horse power'. Imagine that!

Source: thoroedge

Similar machines were used in the late 19th century to perform domestic duties such as churning butter with the help of dogs, sheep or goats. 

Source: neatorama

In 1889, a British engineer named William Cubitt invented a contraption for prisoners. It was meant to ensure that the convicts were never idle and also made good use of the manpower. The device was a mode of punishment, wherein the prisoners were asked to run nonstop for upto 6 hours. 

At times, this would help to grind the grains and pump water for the 'mills'.

Source: myroadtoironman

Combining the original tread wheel with the one used for the mills, the term treadmill came to life. It was only after this that the current fitness version was introduced. 

Which eventually led to the ones jispe hum ghar pe kapde sukhaate hai.

Source: Core