Treadmill


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.
More recently, treadmills have instead been used as exercise machines for running or walking in one place. Rather than the user powering a mill, the device provides a moving platform with a wide conveyor belt driven by an electric motor or a flywheel. The belt moves to the rear, requiring the user to walk or run at a speed matching the belt. The rate at which the belt moves is the rate of walking or running. Thus, the speed of running may be controlled and measured. The more expensive, heavy-duty versions are motor-driven. The simpler, lighter, and less expensive versions passively resist the motion, moving only when walkers push the belt with their feet. The latter are known as manual treadmills.
Treadmills continue to be the biggest-selling exercise equipment category by a large margin. As a result, the treadmill industry has hundreds of manufacturers throughout the world.

History

, a mechanical engineer, developed the first consumer treadmill for home use. Staub developed his treadmill after reading the 1968 book, Aerobics by Kenneth H. Cooper. Cooper's book noted that individuals who ran for eight minutes four to five times a week would be in better physical condition. Staub noticed that there were no affordable household treadmills at the time and decided to develop one for his use during the late 1960s. He called his first treadmill the PaceMaster 600. Once finished, Staub sent his prototype treadmill to Cooper, who found the machine's first customers, including sellers of fitness equipment.
Staub began producing the first home treadmills at his plant in Clifton, New Jersey, before moving production to Little Falls, New Jersey.

Functions

Use for power

Treadmills as power sources originated in antiquity. These ancient machines had three major types of design. The first was a horizontal bar jutting out of a vertical shaft. It rotated around a vertical axis, driven by an ox or other animal walking in a circle and pushing the bar. Humans were also used to power these. The second design was a vertical wheel, a treadwheel, that was powered by climbing in place instead of walking in circles. This is similar to what we know today as the hamster wheel. The third design also required climbing but used a sloped, moving platform instead.
Treadmills as muscle-powered engines originated roughly 4000 years ago. Their primary use was to lift buckets of water. This same technology was later adapted to create rotary grain mills and the treadwheel crane. It was also used to pump water and power dough-kneading machines and bellows.

Use for punishment

Treadmills for punishment were introduced in 1818 by an English engineer named Sir William Cubitt, who was the son of a miller. Noting idle prisoners at Bury St Edmunds gaol, he proposed using their muscle power to both cure their idleness and produce useful work.
Cubitt's treadmills for punishment usually rotated around a horizontal axis, requiring the user to step upwards, like walking up an endless staircase. Those punished walked around the outside of the wheel holding a horizontal handrail for stability. By the Prison Act 1865 every male prisoner over 16, sentenced to hard labour, had to spend three months at least of his sentence in the labour of first class, which consisted primarily of the treadmill.
Punishment treadmills remained in use until the second half of the 19th century; they were typically twenty-foot long paddle wheels with twenty-four steps around a six-foot cylinder. Several prisoners stood side-by-side on a wheel and had to work six or more hours a day, effectively climbing 5,000 to 14,000 vertical feet. While the purpose was mainly punitive, the most infamous mill at Brixton Prison was installed in 1821 and used to grind grain to supplement an existing windmill which Cubitt had previously installed nearby. It gained notoriety for the cruelty with which it was used, which then became a popular satirical metaphor for early-19th century prisons.
The machines could also pump water or power ventilators in mines.

Use for exercise

The first American patent for a treadmill "training machine" was issued on June 17, 1913.
The forerunner of the exercise treadmill was designed to diagnose heart and lung diseases, and was invented by Robert Bruce and Wayne Quinton at the University of Washington in 1952. Kenneth H. Cooper's research on the benefits of aerobic exercise, published in 1968, provided a medical argument to support the commercial development of the home treadmill and exercise bike. The average lifespan of a treadmill is about 7 to 12 years.
File:RIAN archive 555848 Testing on treadmill.jpg|thumb|left|Treadmill test at the medical center of the Olympic village at the 1980 Summer Olympics
Among users of treadmills today are medical facilities, sports clubs, biomechanics institutes, orthopedic shoe shops, running shops, Olympic training centers, universities, fire-training centers, NASA, test facilities, police forces and armies, gyms and even home users.
Treadmill ergometers are now mainly motor driven. Most treadmills have a running deck with a rotating belt. Before and after the running deck, there are two shafts. The belt is stretched between the shafts and the running deck. Safety standards for treadmills are IEC EN 957-1 and IEC EN 957-6.
For medical treadmills applicable norms, standards and guidelines include the Medical Device Regulation, IEC EN 60601-1, EN 62304, EN 14971 and the machinery directive 2006/42/EC.
Medical treadmills are class IIb active therapeutic devices and also active devices for diagnosis. Treadmills deliver mechanical energy to the human body through the moving running belt of the treadmill. They are typically powered by electric motors, around. The subject does not change their horizontal position and is passively moved and forced to catch up with the running belt underneath their feet. The subject can also be attached in a safety harness, unweighting system, various supports or even fixed in and moved with a robotic orthotic system using the treadmill.
Medical treadmills are also active measuring devices. When connected through an interface with ECG, ergospirometry, blood pressure monitor, or EMG, they become a new medical system and can also be equipped to measure VO₂ max and various other vital functions.
Most treadmills have a "cardio mode", where a target heart rate is defined and the speed and elevation are controlled automatically until the subject is in a "heart rate steady state". So the treadmill is delivering mechanical energy to the human body based on the vital function of the subject.
A medical treadmill used for ergometry and cardiopulmonary stress tests and performance diagnostics is always a class IIb medical device either when used as a stand-alone device in a medical environment or when used in connection with an ECG, EMG, ergospirometry, or blood pressure monitoring device.
File:T.J. Creamer ISS022-E-020918.jpg|thumb|250px|NASA astronaut T.J. Creamer, Expedition 22 flight engineer, equipped with a bungee harness, exercises on the Combined Operational Load Bearing External Resistance Treadmill in the Harmony node of the International Space Station.
On the running deck the subject moves, adapting to the adjustable speed of the belt. The running deck is usually mounted on damping elements, so the running deck has shock-absorbing characteristics. A lifting element raises the entire frame including the running deck and simulates a pitch angle for uphill running. Some treadmills can also reverse the running belt to simulate downhill loads. Most treadmills for professional use in the fitness area have table sizes of about long and width, a speed range of about and slope angle of 0–20%.
Larger, more stable treadmills are required for athletes. With some weight relief, sprinters reach temporary speeds of up to and must therefore run on a large deck of up to in length and up to in width. With high physical exertion and an increased risk of falling, a fall-stop unit is required to prevent the subject or patient from falling. This fall-stop device usually takes the form of a safety arch to which a line is attached to an electrical switch. A harness bears the subject, preventing them from falling and shutting down the running belt if necessary.
Motorized or manual treadmills can use a slat belt design instead of a traditional continuous treadmill belt. Slat belt treadmills have individual rubberized slats that support shod or unshod walking and running.
In some offices, employees are provided with treadmill desks so that employees can walk while working on a computer or speaking on the phone.
In treatment centers, treadmills are used with built-in seats left and right for therapists, for example, so the therapists can move the legs of a stroke patient to simulate walking movements and help them learn to walk again. This is called manual locomotion therapy.
Oversized treadmills are also used for cycling at speeds up to, for wheelchair users and in special applications with sturdy running belts for cross-country skiing and biathlon, where athletes perform training and testing exercises with roller skis on a running deck of up to.

Advantages and disadvantages

Advantages

  • Enables the user to adhere to an indoor exercise regime irrespective of the weather.
  • Cushioned treadmill can provide slightly lower impact training than running on outdoor surfaces. Although cushioned belts have mostly been phased out and cushioned replacement belts may be hard to find, many treadmills have rubber or urethane deck elastomers which are superior in cushioning and last longer than cushioned belts. For a time, banana-shaped flexible decks were available which were among the very best for cushioning and were priced at a mid-range level, but these are no longer being sold, perhaps because of the increased manufacturing cost of making flexible decks. Cushioned belts do not last as long as regular belts due to their construction from weaker materials. For calorie burning, incline can be used to significantly reduce impact for a given rate of energy use.
  • Incline setting can allow for consistent "uphill" training that is not possible when relying on natural features.
  • Rate settings force a consistent pace.
  • Some treadmills have programmes so that the user can simulate terrains, e.g. rolling hills, to provide accurate, programmed, exercise periods.
  • The user can watch TV while using the treadmill, thus avoiding sedentary TV viewing.
  • User progress such as distance, calories burned, and heart rate can be tracked.
  • Running backwards "uphill" may develop many antagonistic muscles otherwise ignored when running forward.
  • Running on a treadmill removes the worry about being a target of criminal activity, traffic, uneven terrain, and other outdoor hazards.