
A treadmill is a device generally used for walking, running, or climbing while staying in the same place. Treadmills were introduced before the development of powered machines to harness the power of animals or humans to do work, often a type of mill operated by a person or animal treading the steps of a treadwheel to grind grain. In later times, treadmills were used as punishment devices for people sentenced to hard labour in prisons. The terms treadmill and treadwheel were used interchangeably for the power and punishment mechanisms.
A stationary bicycle (also known as exercise bicycle, exercise bike, spinning bike, spin bike, or exercycle) is a device used as exercise equipment for indoor cycling. It includes a saddle, pedals, and some form of handlebars arranged as on a (stationary) bicycle.
The forerunner of the dumbbell, halteres, were used in ancient Greece as lifting weights and also as weights in the ancient Greek version of the long jump.[3] A kind of dumbbell was also used in India for more than a millennium, shaped like a club – so it was named Indian club.[4][5] The design of the Nal, as the equipment was referred to, can be seen as a halfway point between a barbell and a dumbbell. It was generally used in pairs, in workouts by wrestlers, bodybuilders, sports players, and others wishing to increase strength and muscle size.