punching bag

A stuffed or inflated leather bag that is usually suspended so that it can be punched with the fists for exercise.

Background

A punching bag is a round or cylindrical piece of athletic equipment used by professional boxers for training and by amateurs for exercise. The bags come in a variety of sizes for a variety of uses. The largest, known as the heavy bag, is used to develop footwork and power. The timing bag, usually suspended from the ceiling and floor by bungee cords, develops timing and hand-eye coordination. The small speed bag develops hand speed, coordination, and rhythm.

History

The sport of boxing dates to the ancient Olympic Games. The first gold medal in boxing was awarded to a fighter named Onomastos in the twenty-third Olympiad. The earliest boxers were trained as if soldiers for war. There was little sophistication in the sport. Participants boxed bare-handed. One of the earliest boxers, Eurydamus, was known for his fierceness; he was reported to have swallowed his own teeth during a match rather than admit that he had been severely injured.

By the beginning of the first century A.D., boxing had been forbidden and would not be seen again in the sports world until the eighteenth century in Great Britain. The first recorded English boxing champion was James Figg, who fought in the early part of the 1700s. Figg was followed by Jack Broughton in the mid century. Broughton was considered a master of blocking, parrying, and hitting on the retreat. In 1743, Broughton created a boxing code of conduct called the London Prize ring rules. (The rules were later revised and became known as the Revised London Prize Ring rules.) When Broughton's patron, the Duke of Cumberland, asked him to teach some of his well-to-do friends to box, Broughton devised special gloves, or mufflers, so that these "gentlemen" would not injure their hands.

The sport was further refined by the establishment of the Queensberry Rules, which were created under the sponsorship of another patron of the sport, John Sholto Douglas, the eighth marquess of Queensberry. These rules, still in effect today, set round limits, established glove weights, and created fighter classes by weight. They also forbade hits below the belt, to the back of the head, to the neck and to the kidneys.

It is not certain when the punching bag became part of the boxer's training regiment. The United States Office of Patents and Trademarks awarded a patent for the punching bag to Simon D. Kehoe in 1872. Since that time, others have made improvements to better simulate the human body.

With the increased interest in physical fitness and the advent of health clubs in the 1970s, amateurs became more interested in boxing as a form of fitness. By the beginning of the twentieth century, large numbers of people in the United States were enrolled in some type of boxing class.

Design

Paper patterns are created for the various panel sizes. The patterns are placed on sections of leather. Using chalk or grease pencils, a worker traces the shape of the pattern onto the leather.

A striking bag is usually constructed of two leather balloons, inserting one inside the other, then inflating the inner balloon with air to create a resilient ball.

Raw Materials

The earliest striking bags were made from kangaroo skin. However, goatskin is now more commonly used for small punching bags. The animal skin is dipped in strong chemicals to remove the hair prior to being cured in salt water. After curing, the skin is stretched and dried and ready for use in manufacturing.

The larger, heavy bags are constructed of polyvinyl or canvas. Canvas is a heavy cotton material. Polyvinyl is a plastic material developed during the Second World War. It is made from the byproducts of petroleum and coal.

A heavy, coated synthetic thread, typically nylon and polyester, is used to stitch the pieces of leather together.

While the striking bag is inflated with air, the heavy bags are filled with sand or finely shredded wood clippings.

Snaps, hooks, zippers, chainlink, and cord lacings are used to close the bags, attach them to the rebound board, and/or attach them to other bags.

The Manufacturing
Process

The manufacture of striking and training bags are accomplished through a combination of manual and mechanical steps.

Constructing the striking bag

1. The leather for the bag is usually derived from goatskin. The skin must be tanned by placing it in rotating drums filled with a salt and water solution. The salt ingredient is typically chromium. In approximately eight hours, the chromium soaks through the skin. The chromium is then "fixed" to the skin by the addition of an alkaline chemical such as sodium carbonate or bicarbonate.
2. The tanned skin is run through a machine that shaves it to the desired thickness. After that, it is passed through a wringer to remove excess moisture.
3. Once the leather has been dried and prepared, it is ready to be cut. First, patterns that are the exact size and shape of each panel are traced onto the leather using chalk or a grease pen. Then, these sections are manually cut by workers using leather-cutting shears or knives.

   Some manufacturers employ automated cutting machines in order to create the panels. In these cases, a very sharp metal component is constructed in the exact size and shape of the panel. As the leather passes under this metal die, the die cuts down into the fabric similar to a cookie cutter.

4. The next step is to sew the leather panels together. The bags are constructed with either four or six panels, depending on the desired size. When sewn together, the panels create a pear-shaped balloon. Heavy duty nylon or polyester thread is used to stitch the pieces to one another. The stitching is performed by a worker operating a sewing machine.
5. Once the two bags have been sewn together, the inner bag needs to be inflated with air. An inflation device called a collar is inserted into the inner bag just before the two bags are completely stitched. A valve on the inflation collar regulates the amount of air that is blown into the outer bag. Inflated air is measured in terms of pounds per square inch, or psi. The striking bag is inflated to a measure of 4—4.5 psi. A cap on the collar then clamps the bag wall to the collar skirt.
6. The final step involves manually connecting the striking bag to an overhead rebound board by a piece of flexible metal combined with a ball-and-socket joint. The rebound board may be constructed of wood or a thick, durable plastic.

Constructing the training bag

1. Training bags are usually made of vinyl or canvas. The vinyl or canvas is cut from patterns using a garment knife or die cutting machine, just as the leather was cut for a striking bag. The round top and bottom pieces are cut on a punch press.
2. Once all of the material has been cut to the specified size, the pieces are sewn together. Again, strong nylon or polyester thread is used. The pieces are stitched together by a worker operating a sewing machine. The top is left open.
3. In order to fill the bag, it is placed over a sleeve attached to a hopper. The stuffing materials, such as shredded wood clippings or sand, are loaded into the hopper. Forced air fills the bag with the stuffing materials.
4. The top of the bag is sealed by sewing tabs of vinyl or canvas to the top edges of the bag. A round length of tubing, called a torus, is threaded through the tabs. Four metal rings, attached to four chains, are fitted around the torus. The top is then closed with laces or with zippers.

Quality Control

In order to ensure that bags have been properly constructed, manufacturers will periodically test the final product. Either manually or using automatic robotic devices, the bags undergo rigorous tests that determine the durability of the seams, the outer material, and the hanging components. To test the seams, the fabric may be pulled in opposing directions at measured forces or repeatedly tugged and timed. Punching the bag in a manner similar to how it will be used is also another quality control measure. It is important to ensure that the final product can withstand excessive wear and tear and that the primary components will remain in tact after use, especially considering the purpose of this product.

Byproducts/Waste

Scraps of leather, vinyl, canvas, thread, and fill material are the excess waste produced through the manufacture of punching bags. Depending on the size of the scrap fabrics, they will either be reused for other goods produced by the company or, more likely, disposed of in the trash. Any pieces of thread will also be thrown away. Fill material may be recollected for the same use if it is still in good condition. Excess wood clippings could be safely incinerated and sand can be disposed of at an appropriate dump site if not adequate for reuse.

The Future

Manufacturers continue to make improvements to punching bags in an effort to better simulate the human body and its reactions to strikes. A patent was issued in 1998 by the United States Trademark and Patent Office for a training apparatus that combined a head-sized striking bag to a hanging training bag.

Other innovations are designed to attract the amateur boxing enthusiast. One such version is the Soc-o-Mac, developed by Howard "Mack" McConnell in 1976. The Soc-o-Mac weighs about 450 lb (204 kg) and sits in a weighted steel pan on the floor. The steel pan's curved bottom keeps the bag upright and allows it to roll over and back up when hit.

In the early 1980s, Tom Critelli, a former deputy sheriff invented a water-filled bag that can be drained and refilled. Another invention in the last decade of the twentieth century, was the SoloSpar, an automated heavy bag that moves when punched and talks back when struck in certain spots.

Where to Learn More

Books

Carpenter, Harry. Boxing: A Pictorial History. Chicago: Henry Regnery, 1975.

Periodicals

Lidz, Franz. "A Fighter Would Have to be All Wet." Sports Illustrated (20 June 1983): 12.

McDonnell, Terry. "Punchline." The Business Journal (serving Phoenix and Valley of the Sun) (19 June 1989): 1.

Millman, Chad. "Automated Attitude." Sports Illustrated (21 February 1994): 89.

Other

"U.S. Patent 5142758: Punching Bag Construction and Suspension." Delphion Web Page. December 2001. <http://www.delphion.com> "U.S. Patent 5769761: Striking Bag Training Apparatus." Delphion Web Page. December 2001. <http://www.delphion.com>.

[Article by: Mary McNulty]

The noun has one meaning:

Meaning #1: an inflated ball or bag that is suspended and punched for training in boxing
  Synonyms: punching ball, punchball

A muay thai fighter "working his hands" on a heavy bag.

A punching bag is a sturdy bag designed to be repeatedly punched, for use in physical exercise or stress relief in order to improve one of three areas: physical strength, aerobic fitness, or punching technique.

Contents 1 History 2 Construction 2.1 Types of bag 2.2 Safety precautions 3 Turn of phrase 4 References

History

Punching bags have been used in martial arts and swordplay for as long as there has been a written history of military training.^[1] Similar apparatus in Asian martial arts include the Okinawan makiwara and the Chinese mook jong, which may have padded striking surfaces attached to them.^[2]

In martial arts and combat sports such as Karate, Taekwondo, and Muay Thai; heavy bags, standing bags, and similar apparatuses have been adapted for practicing kicking and other striking maneuvers in addition to developing punching technique.^[2]

Construction

Punching bags are often filled with grains, sand, rags, or other material and are usually hung from the ceiling or affixed to a stand.^[3] Other bags have an internal bladder to allow them to be filled with air or water. The design of a punching bag allows it to take repeated and constant physical abuse without breaking. The bag must also absorb the impact of blows, without causing harm to the user.

Types of bag

There are different types of punching bags, with different names based on their size, use and mounting method. Almost all punching bags are covered with leather or synthetic materials such as vinyl which resist abrasion and mildew. Canvas is also used as a bag material where there is lower use and humidity.

Speed bags are small, air-filled bags anchored at the top to a rebound platform parallel to the ground. Speed bags help a fighter learn to keep his hands up, improve hand-eye coordination and learn to shift weight between feet when punching. They are also known as SpeedBalls or Speed Ball Bags. Generally you will find that again, they are filled with air (mostly) and fitted around a tight PU based or other leather material.

Swerve balls / floor to ceiling balls are almost the same as Speed balls. Swerve balls - or floor to ceiling balls, these are almost the same as Speed balls with the only difference that the bag size shape and material may be different and that the cable system is attached to the ceiling and a clip on the floor - when the boxer places any motion on the ball, it tightly reacts by swinging fast towards them, the object is to swerve, punch, dodge and learn about co-ordination. The harder and faster they are hit - the more they rebound and react in different motions of angles, thus giving greater practice to the fighter.^[1][2]

A comparison of a speed ball system and a floor to ceiling bag system

Double-end bags or Focus bags are light, round bags, often anchored to floor and ceiling with elastic or semi-elastic materials. These types of bags are used to practice mobility and accuracy on a moving target.^[1][2]

Maize bags are not punched with great force but are used in boxing training to improve the athlete's head motion and ability to evade an opponent's punch, their name deriving from the fact that traditionally they are filled with maize.

A heavy bag is a larger, cylindrical bag, usually suspended by chains or ropes for practicing powerful body punches.^[1][2]

Pedestal bags or tower bags are heavy bags mounted on a weighted pedestal rather than being hung from above. Other variations on the standard heavy bag include horizontal suspension from both ends to practice uppercut punches and non-cylindrical shapes.

A "body opponent bag" on a pedestal mount.

Body-shaped training aids such as the modern "body opponent bag" are made primarily of synthetic materials, and punching bags are sometimes mounted on a weighted pedestal rather than hanging from above. These are not punching bags in the strict sense, but modern versions of apparatus such as the wooden man apparatus of Chinese Wing Chun, the medieval quintain and target dummies used in modern bayonet training. Large inflatable balloons with weighted bases are another kind of punching bag, often painted with a picture and sold as a children's toy.

A "upper cut bag" for specialist training.

The upper cut punch bag started showing itself towards the beginning of the century. With so many different variations of bags and training equipment for boxing taking off, the upper cut bag was and is still a common sight in clubs and gyms. Designed for upper cut practice, jabbing, curl punching and low quick burst of high and low punching practice. It allows the fighter to punch at different lengths, different speeds and different forces compared to the standard average 4ft straight pu (polyurethane) punch bags.

Safety precautions

Powerful strikes to the heavy bag aren't recommended for younger athletes, lest they risk damage to their still-developing bones. Adult athletes who strike the bag with full force are encouraged to use hand wraps and bag gloves to avoid injuries such as the boxer's fracture of the fifth metacarpal.^[1][2]

Turn of phrase

A "punching bag" is a name used for a person who is the victim of bullying.

References

1. ^ ^{a b c d e} DePasquale, Peter (1990), The Boxer's Workout, Fighting Fit, 176, ISBN 0962705004
2. ^ ^{a b c d e f} Lee, Bruce (1977), Bruce Lee's Fighting Method,Vol. 2: Basic Training, Ohara, 128, ISBN 0897500512
3. ^ "NBC 30 Connecticut". Family's Punching Bag Holds Smelly Surprise. 2007-05-17. http://www.nbc30.com/news/13331924/detail.html?rss=har&psp=weird-news. Retrieved on 2007-05-26. 

Look up punching bag in Wiktionary, the free dictionary.

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)