James Lafond recounts the history of the punching bag:
The earliest form of striking equipment was not used for punching, but for kicking and other strikes specific to the pankration, the ancient Greek form of MMA. This bag was an entire pig skin filled with sand and hung upside down by the tail. The strike depicted being used on this equipment in the surviving artwork is the precise kick that was recently used by Anderson Silva to KO Vitor Belfort. A later source mentions the use of this device for clinch practice.
The second type of ancient striking equipment was a hanging ‘effigy’, a stuffed replica of a human torso, analogous to the freestanding anatomical ‘bobs’ preferred today for martial arts practice in karate schools.
The third type of ancient punching bag, preferred by boxers throughout antiquity, was a sack of barley hung from a roof beam. This item was about the size of a human head and moved more like a maize ball [the small bag used for head movement drills in some gyms] than any modern piece of striking equipment.
Bare-knuckle boxers had learned their art without the aid of striking equipment for two hundred years, when, in 1877, American Middleweight Champion Mike Donovan began hitting a rugby ball in Troy New York, and then got the bright idea to hang it from the ceiling. Within ten years pro boxers [who, at this stage fought with bare-knuckles, driving gloves, and sometimes 6 oz to 8 oz ‘mufflers’] were using three types of punching bags based on the original ball that Mike had begun bouncing off of walls and punching back in Troy.
Only ten years into their use, punching bags were considered indispensable tools for developing combinations, or as combination punching was then called ‘two-handed punching’. A boxer was supposed to strike the bag with the bare-knuckles to condition his hands and learn how to avoid hand injuries.
The ‘flying bag’ was a rugby ball suspended from the ceiling on a string, and based on its name, was used to train cutoff punches and counter punches. It could not — when hung from the high ceiling of a barn or dance hall — be of much use for training combination punches. For men who fought without hand protection this was an important tool. To avoid chasing it and to work on combinations it was sometimes hung in a corner from a low ceiling.
The ‘heavy bag’ was a chamois cloth sack stuffed with horse hair [which was being used to stuff gloves up until the 1970s] that only weighed 10 to 20 pounds. It was usually hung from a rope and swung along a wide arc. If it was hit with a vertical fist [the common bare-knuckle fist orientation] or while it was swinging at the fighter, wrist injury was likely. It was not a favorite tool, and tended to be avoided.
The ‘oval bag’ was a large air-bladder double-ended reflex bag. This was the most popular type of bag in gyms on the eve of the gloved era circa 1890. It would fall into obscurity but survive. Film from Ray Robinson’s training camps [circa 1950] show him working this large double-ended bag.
The three types of bag described above would evolve into the three standard pieces of striking equipment present in boxing gyms until the early 1980s.