The advantages of running on a treadmill

In 1817, Sir William Cubitt, an eminent British civil engineer, designed a machine called treadwheel to reform idle prisoners and use their power to be productive. Their work was used to pump water and grind grains, the reason why the machine was later called a treadmill. Some say a certain prison guard claimed that it was the monotonous steadiness and not the work intensity which made the machine...