Stirrup



A stirrup is a light frame or ring that holds the foot of a rider, attached to the saddle by a strap, often called a stirrup leather. Stirrups are usually paired and are used to aid in mounting and as a support while using a riding animal (usually a horse or other equine, such as a mule). They greatly increase the rider's ability to stay in the saddle and control the mount, increasing the animal's usefulness to humans in areas such as communication, transportation and warfare.

In antiquity, the earliest foot supports consisted of riders placing their feet under a girth or using a simple toe loop. Later, a single stirrup was used as a mounting aid, and paired stirrups appeared after the invention of the treed saddle. The use of paired stirrups is credited to the Chinese Jin Dynasty and came to Europe during the Middle Ages. Some argue that the stirrup was one of the basic tools used to create and spread modern civilization, possibly as important as the wheel or printing press.

Modern stirrups come in a wide variety of styles, sizes and materials and are attached to most saddles by means of adjustable stirrup leathers, which can be altered in length to fit both the size of the rider and the need to remain over the horse's optimal center of balance for a given equestrianism discipline. There are safety concerns associated with the use of stirrups, including a risk that a fallen rider may get their foot caught in the stirrup and be dragged by the horse, or that long hours of use without rest may cause problems in the human foot's Peroneus Tertius tendon. Stirrups are safer to use when riding boots are worn, and proper sizing and placement of the foot on the stirrup increases both safety and usability.

Etymology
The English word "stirrup" stems from Old English stirap, stigrap, Middle English stirop, styrope, i.e. a mounting or climbing-rope. From Old English stīgan "to ascend".

History
The stirrup, which gives greater stability to a rider, has been described as one of the most significant inventions in the history of warfare, prior to gunpowder. As a tool allowing expanded use of horses in warfare, the stirrup is often called the third revolutionary step in equipment, after the chariot and the saddle. The basic tactics of mounted warfare were significantly altered by the stirrup. A rider supported by stirrups was less likely to fall off while fighting, and could deliver a blow with a weapon that more fully employed the weight and momentum of horse and rider. Among other advantages, stirrups provided greater balance and support to the rider, which allowed the knight to use a sword more efficiently without falling, especially against infantry adversaries. Contrary to common modern belief, however, it has been asserted that stirrups actually did not enable the horseman to use a lance more effectively (cataphracts had used lances since antiquity), though the cantled saddle did.

Early development
The invention of the stirrup occurred relatively late in history, considering that horses were domesticated in approximately 4500 BC, and the earliest known saddle-like equipment were fringed cloths or pads with breast pads and cruppers used by Assyrian cavalry around 700 BC.

The earliest manifestation of the stirrup was a toe loop that held the big toe and was used in India late in the second century BC, though may have appeared as early as 500 BC. This ancient foot support consisted of a looped rope for the big toe which was at the bottom of a saddle made of fibre or leather. Such a configuration was suitable for the warm climate of south and central India where people used to ride horses barefoot. A pair of megalithic double bent iron bars with curvature at each end, excavated in Junapani in the central Indian state of Madhya Pradesh have been regarded as stirrups although they could as well be something else. Buddhist carvings in the temples of Sanchi, Mathura and the Bhaja caves dating back between the 1st and 2nd century BC figure horsemen riding with elaborate saddles with feet slipped under girths. In this regard Sir John Marshall described the Sanchi relief as "the earliest example by some five centuries of the use of stirrups in any part of the world". Later, a single stirrup was used as a mounting aid by a nomadic group known as the Sarmatians.

The invention of the solid saddle tree allowed development of the true stirrup as it is known today. Without a solid tree, the rider's weight in the stirrups creates abnormal pressure points and make the horse's back sore. Modern thermography studies on "treeless" and flexible-tree saddle designs have found that there is considerable friction across the center line of a horse's back. A coin of Quintus Labienus, who was in service of Parthia, minted circa 39 B.C. depicts on its reverse a saddled horse with hanging objects. Smith suggests they are pendant cloths, while Thayer suggests that, considering the fact that the Parthians were famous for their mounted archery, the objects are stirrups, but adds that it is difficult to imagine why the Romans would never have adopted the technology.

In Asia, early solid-treed saddles were made of felt that covered a wooden frame. These designs date to approximately 200 BC. One of the earliest solid-treed saddles in the west was first used by the Romans as early as the 1st century BC, but this design also did not have stirrups. The first dependable representation of a rider with paired stirrups was found in China in a Jin Dynasty tomb of about AD 322. The stirrup appeared to be in widespread use across China by AD 477.

Stirrups in Europe
By the late 6th or early 7th century, primarily due to invaders from Central Asia, such as the Avars, stirrups began spreading across Asia to Europe. In terms of archaeological finds, the iron pear-shaped form of stirrups, the ancestor of medieval European types, has been found in Europe in 7th century Avar graves in Hungary. A total of 111 specimens of early Avar-age, apple shaped, cast-iron stirrups with elongated suspension loop and flat, slightly inward bent tread had been excavated from 55 burial sites in Hungary and surrounding regions by 2005. The first European literary reference to the stirrup may be in the Strategikon, traditionally ascribed to the Byzantine Emperor Maurice, and therefore written sometime between 575 and 628 AD, but this is widely disputed, and the work placed in the eighth or ninth century by others. Maurice's manual notes the appropriate equipping of Imperial cavalry: "the saddles should have large and thick clothes; the bridles should be of good quality; attached to the saddles should be two iron steps [skala], a lasso with a thong...." Dennis notes that the lack of specific Greek word for stirrup evidences their novelty to the Byzantines, who are supposed to have adopted these from their bitter enemy the Avars, and subsequently passed them on to their future enemies, the Arabs. An early 7th-century date is secured for most Hungarian finds of stirrups with elongated suspension loops, though some of these must even be dated to before 600. Literary and archaeological evidence taken together may indicate that the stirrup was in common military use in South-Central Europe and the Eastern Mediterranean by the latter half of the 6th century, with the Byzantine Empire having them in use by the year 600.

By the 8th century stirrups began to be adopted more widely by Europeans. The earliest stirrups of western Europe, those of Budenheim and Regensburg, were either brought from the Avar Khaganate as booty or gifts, or were local imitations of stirrups in use at that time among Avar warriors. However, the Avar-style stirrups were not as widely adopted in western Europe. Stirrups do not appear in the Merovingian and Italo-Lombard milieu in large numbers, nor as frequently as within the Carpathian Basin. Most other stirrups found in Germany that date to the 7th century do not resemble the iron Avar style commonly found in burial assemblages from Hungary and neighboring regions. Instead, hanging mounts occasionally found in burial assemblages in southern Germany suggest the use of wooden stirrups. The scarcity of early-medieval stirrup finds in western Europe was noted by Bernard Bachrach: "Out of 704 eighth century male burials excavated in Germany untill [sic] 1967, only 13 had stirrups." The earliest stirrups in the Baltic region are replicas of those in existence in Germany during the 7th century. In northern Europe and Britain the metamorphosis of earlier wood, rope and leather forms of stirrups to metal forms can be seen in the archeological record, “suggesting that one or more of the early forms have parallel development with those in Hungary, rather than being derived solely from the latter region.” "In Scandinavia two major types of stirrups are discerned, and from these, by the development and fusion of different elements, some almost certainly of central European origin, most other types were evolved." The first main type, Scandinavian type I, appears to owe little to Hungarian forms. The earliest variety of this type can be dated to the 8th century in Vendel grave III in Sweden. The second principal type in North Europe has, as its most characteristic feature, a pronounced rectangular suspension loop set in the same plane as the bow, as found amongst the Hungarian examples, and is predominantly centered in Denmark and England during the later 10th and 11th centuries. A variant of this type, called the North European stirrup, has been dated to the second half of the 10th century in Sweden, found at the boat-burial cemetery at Valsgärde.

In Denmark from the 920s to the 980s, during the reign of the Jelling kings, many leading Danes were buried with military honors and equipped with stirrups, bits and spurs, in what are called cavalry-graves, found mostly in north Jutland. Into England, it is argued, stirrups were not introduced by the Scandinavian settlers of the 9th century but are more likely related to later Viking raids led by Cnut the Great and others during the reign of king Aethelred (978-1013).

In what today is France, Charles Martel distributed seized lands to his retainers on condition that they serve him by fighting in the new manner, which some attribute to his recognizing the military potentialities of the stirrup. Later, Charlemagne ordered his poorer vassals to pool their resources and provide a mounted and armed knight, though the system proved unworkable, and instead the system of distributing land to vassals based on a knight's service was developed.

Great Stirrup Controversy
The introduction of the stirrup not only made the mounted warrior supreme in medieval warfare, but may have initiated complex and far-reaching social and cultural changes in Europe. Some scholars credit this use of the stirrup to the birth of feudalism and its subsequent spread into Northern Italy, Spain, Germany and into the Slavic territories. It is argued that the rising feudal class structure of the European Middle Ages derived ultimately from the use of stirrups: "Few inventions have been so simple as the stirrup, but few have had so catalytic an influence on history. The requirements of the new mode of warfare which it made possible found expression in a new form of western European society dominated by an aristocracy of warriors endowed with land so that they might fight in a new and highly specialized way." Other scholars dispute this assertion, suggesting that stirrups may provide little advantage in shock warfare, but are useful primarily in allowing a rider to lean farther to the left and right on the saddle while fighting, and simply reduce the risk of falling off. Therefore, it is argued, they are not the reason for the switch from infantry to cavalry in Medieval militaries, nor the reason for the emergence of Feudalism.

Japanese stirrups
Stirrups (abumi) were used in Japan as early as the 5th century. They were flat bottomed rings of metal-covered wood, similar to European stirrups. The earliest known examples were excavated from tombs. Cup-shaped stirrups (tsuba abumi) that enclosed the front half of the rider's foot eventually replaced the earlier design.

During the Nara period, the base of the stirrup which supported the rider's sole was elongated past the toe cup. This half-tongued style of stirrup (hanshita abumi) remained in use until the late Heian period when a new stirrup was developed. The fukuro abumi or musashi abumi had a base that extended the full length of the rider's foot and the right and left sides of the toe cup were removed. The open sides were designed to prevent the rider from catching a foot in the stirrup and being dragged. The military version of this open-sided stirrup (shitanaga abumi) was in use by the middle Heian period. It was thinner, had a deeper toe pocket and an even longer and flatter foot shelf. This stirrup stayed in use until European style-stirrup rings were reintroduced in the late 19th century. It is not known why the Japanese developed this unique style of stirrup. The abumi had a distinctive swanlike shape, curved up and backward at the front so as to bring the loop for the leather strap over the instep and achieve a correct balance. Most of the surviving specimens from this period are made entirely of iron, inlaid with designs of silver or other materials, and covered with lacquer. In some examples there is an iron rod from the loop to the footplate near the heel to prevent the foot from slipping out. The footplates are occasionally perforated to let out water when crossing rivers, and these types are called suiba abumi. There are also abumi with holes in the front forming sockets for a lance or banner.

Stirrup leathers
Because a rider must be able to move his or her legs while riding, stirrups cannot be attached on the body of the saddle itself, but rather must be attached in a manner that allows the rider's leg a full range of motion. Therefore, stirrups are attached to a saddle by means of adjustable straps, called stirrup leathers. Depending on the design of a saddle, stirrup leathers may be attached to a "stirrup bar," a small forged steel bar embedded into the saddle tree, or may be wrapped around the bars of the tree itself. Because different riders are of different heights, and stirrups also may need to be adjusted up or down to accommodate different types of activity, stirrup leathers have buckles and holes that allow length to be adjusted.

On an English saddle, leathers are quite thin, only about one inch wide. On a western saddle, they are very heavy, three to four inches wide on the side closest to the horse, and even wider, expanded into a decorative "fender" on the outside (which also protects the rider's legs from the sweat of the horse). Stirrup leathers on other saddle designs fall in between the extremes represented by the English and western saddles.

Stirrup leathers are usually manufactured so that the smooth side of the leather faces the wearing surface, as the smooth side wears less quickly than the rough side. There are also modern alternatives to leather, including nylon, plastic covered nylon (biothane being one example) or leather over a nylon reinforced core. These new "leathers" may last longer and also resist stretching. On the other hand, they may chafe and rub the leg, and poorly made products may break more easily than leather.

As the rider's whole weight must be carried at one side when mounting, on an English saddle, one stirrup leather often becomes stretched longer than the other, usually the left one, because most mounting occurs on that side. While a simple adjustment of the leather can even up the stirrups, to preserve the integrity and longevity of the leathers, they should be switched to the opposite sides from time to time. On a western saddle, with a heavier, permanently installed fender and stirrup leather that cannot be switched, stretching is slower and less extreme, though it also occurs in this type of saddle. Any unevenness in the leathers can be managed by adjusting the stirrup length, and if necessary, by adding extra holes in the leathers to allow them to be buckled at an intermediate point between the existing prepunched holes provided by the saddle manufacturer.

Adjustment and uses of stirrups
There are two basic methods of using stirrups, a shorter stirrup to allow more mobility and a longer stirrup to allow greater control. The stirrup itself is similar, but the length of the stirrup leather is different. In each case, the stirrup length allows the rider to remain over the center of balance of the horse for the average speed characteristic of the discipline; the faster the horse travels, the more forward the rider must be positioned, and hence the shorter the stirrup.

Long stirrups allow the rider to ride with a long leg, with the knee relaxed and only slightly bent, allowing a deep and stable seat in the saddle. When riding a long stirrup, the rider has excellent control of the horse and the greatest ability to feel and communicate with the horse via the riding aids. This provides a sturdy base for activities where precision is required or when the rider is at risk of being unseated. For both reasons, long stirrups were thus the choice of heavy cavalry such as the medieval knights, who fought in close quarters and used weapons such as the lance and long, heavy swords. Historically, this type of stirrup adjustment and the riding seat it produced was called la brida. Today it is the choice for dressage and many types of western riders.

Shorter stirrups require a rider to keep the knees bent at a greater angle. When riding in a short stirrup, the rider has the ability to partially stand up and get the seat clear of the saddle. This allows more mobility than a longer stirrup would, but at the cost of having less feel of the horse and less security. It is a position designed to help the horse achieve greater speed, and also allows the rider greater physical mobility in the saddle. When riding with short stirrups, the rider often adopts what is known as a forward seat, thus inhibiting the horse's balance and athletic maneuverings as little as possible. In the past, this style was preferred by light cavalry. These fighters required speed and needed the flexibility to turn their own bodies in any direction to use light weapons such as the bow, javelin, short swords, and later, the rifle and pistol. The horsemen of Central Asia, such as the Mongols, used this type of stirrup, as did the Islamic Bedouin and Moors of the Middle East and North Africa. Historically, this type of stirrup adjustment and the seat it produced was called la jineta. Modern Jockeys, eventers, and show jumping riders use this type of stirrup, as do some cowboys when performing certain jobs that require a forward position to allow agility of horse and rider, such as calf roping

While an inexperienced rider may feel more secure with a slightly too-short stirrup, in reality, it is actually easier to be thrown from the horse because the rider's legs act as a stabilizing agent, much in the same way the long pole of a tightrope walker balances the acrobat. Obviously, a stirrup leather so long that a rider cannot reach it is useless, and a stirrup length that does not allow a rider with a properly positioned leg to keep the heel lower than the toe is also easily lost. However, shortening the stirrup until the rider feels they will not lose the stirrup is counterproductive; the goal of correct equestrianism is to make maximum use of the leg. Lengthening the leg creates a more secure seat, while shortening the stirrup is done only to accommodate the needs of the horse to perform athletic movement. Thus correct stirrup length creates a balance between control and mobility that fits the discipline performed.

There are a spectrum of stirrup lengths, which the rider may chose depending on the purpose. For example, in dressage, the longest possible stirrup length is used in order for the rider to have complete control over every nuance of the horse's movement. Likewise, a very long stirrup is used in the western sport of cutting, where, though the rider relinquishes control to the horse, requires maximum security to stay in the saddle during the rapid stops, turns and bursts of speed the horse uses when maneuvering cattle. For a comfortable ride over long hours at slow speeds, the long stirrup is also preferred by trail riders.

Riders jumping low fences may wish for an intermediate length stirrup that can allow the horse some freedom of movement, while supporting the rider over the fence, and still providing enough leg for excellent communication. A rider travelling rapidly cross-country, over varying terrain while fox hunting or endurance riding, will also have an intermediate stirrup, needing to strike a compromise between mobility for the horse and the need of the rider to not be unseated. In the western rodeo sport of calf roping, a moderately short stirrup is also required to help the horse to sprint quickly from the box, and to allow the cowboy the freedom to swing a lariat.

A show jumping rider will have a shorter stirrup than other English riders, in order to maximize the jumping effort of the horse. However, the rider also has the challenge of staying on over the fence and controlling the horse through rapid changes of pace and direction, so still needs some length of leg for stability.

Jockeys must be completely off their horse's backs, balanced well forward over the withers, to allow their mount optimum speed in a long, galloping stride. Therefore they have the shortest possible stirrup length. The cost for maximum speed is minimum control and security. Jockeys must be in superb muscular condition and possess outstanding balance; they cannot achieve the finesse of leg aids needed in other equestrian sports, and must rely primarily on the use of their seat and a crop for speed, and on their arm strength for directional control or slowing down. Their relative lack of control is clearly demonstrated by the use of "pony" horses to lead the race horse and jockey to the track, the use of assistants at the starting gate to load the horses, and the availability of outriders (all with much longer stirrups) to assist the jockey at the end of a race or in the event of an accident. If the horse does anything but run in essentially a straight line with long gradual curves, or if anything goes seriously wrong, jockeys can easily be thrown, as their high rate of injury so amply illustrates.

Weaknesses in design
The stirrup design does have two inherent design flaws. The first is a safety issue: even with a properly fitted stirrup, there are several ways in which the rider's foot can be trapped and cause the rider to be dragged in the event of a fall from the horse. The second is the potential negative impact on the health of the human foot.

One reason riders can become hung up is due to improper stirrup sizing. If the stirrup is too large, the foot can go through the stirrup opening and be caught. If the stirrup is too small, the foot can become trapped more easily as the foot cannot free itself. The main reason for a rider to become hung up in the irons is due to the 'closing door effect' of a lost stirrup trying to return to lie flat against the side of the horse. When the rider falls and the stirrup is free, it tends to return to its home position flat against the horse's side. As the stirrup returns to the horse, the opening for the foot gets smaller and smaller and can catch a falling rider's boot in that smaller opening.(see Fitting the stirrup, below). Proper stirrup placement, on the ball of the foot, instead of jammed "home" clear up to the arch, also lowers the risk of a rider being dragged.

Modern English saddles are designed with a stirrup bar that allows the stirrup leathers to fall from the saddle if the rider starts to be dragged. Some English stirrups are also designed with breakaway sides or non-standard designs intended to make it easier for the foot to come out of the stirrup when necessary.

Western saddles have significantly wider stirrups, particularly at the tread, to minimize this risk. Sometimes, they are equipped with tapaderos, leather covers over the toe that close each stirrup from the front. A tapadero prevents the rider's boot from slipping through and also prevents brush encountered while working cattle on the open range from poking through the stirrup, injuring or impeding the horse or rider. However, the tapadero is not common in modern times and is not allowed in most show competition.

The second design flaw of the stirrup affects the health of the human foot. The rider's whole weight is at times supported entirely by the stirrups. During these periods, excessive pressure can be exerted on the peroneus tertius tendon, which runs along the lateral side of the foot. In extreme cases, stirrups have been found to cause damage to the tuberosity of the fifth metatarsal bone. Over long periods of extreme use, this can cause various medical conditions ranging from simple impaired walking to severe pronation or supination of the foot. Normal riders, however, generally have no related problems, even over a lifetime of riding. Disciplines that require long hours in the saddle, such as endurance riding and some types of western riding on a working ranch, often use a wider stirrup to provide more support to the foot.

For the comfort of the horse, all stirrups require that the saddle itself be properly designed. The solid tree of the saddle distributes the weight of the rider over a greater surface area of the horse's back, reducing pressure on any one area. If a saddle is made without a solid tree, without careful engineering, the rider's weight in the stirrups and leathers can create pressure points on the horse's back and lead to soreness. This is especially noticeable with inexpensive bareback pads that add stirrups by means of a strap across the horse's back with a stirrup at each end.

Riding boots
The risk of being dragged by a foot caught in the stirrup spawned an adaptation in riding footwear: Riding boots have a raised heel of at least a half-inch, and in special designs like the western cowboy boot, often more. This "ridge" created by the raised heel will usually catch on the bottom of the stirrup, preventing the foot from slipping through the stirrup and dragging the rider. Riding boots also have a smooth sole that can easily slide in and out of the stirrup.

Footwear such as a tennis shoe or a hiking boot is considered inappropriate for riding both because the shoe has little or no raised heel and because the heavy tread that provides traction for athletic endeavors can cause the foot to catch in the stirrup and become trapped. Modern synthetic materials have allowed the design of riding boots that will slide from a stirrup but are also comfortable for walking, with a sole using varying hard and soft materials that provides reasonable traction with a minimal amount of raised tread.

Modern stirrups
The modern stirrup can be made from a variety of materials including metals, wood and certain synthetics. Stirrups with a wider tread tend to be more comfortable and a rider is less likely to become hung up in the event of a fall. Thinner stirrups provide greater security. Though the underlying design of a flat bottom and curved top have not significantly changed from the earliest artifacts, some modifications have made the stirrup safer and more comfortable.

One of the most dangerous problems with the stirrup is that the rider can get a boot stuck in it in the event of a fall, which would result in the person being dragged. Several different designs have been developed to allow the stirrup to break away, fall off or easily release the foot if the rider falls. Other modern stirrup designs have changed the angle or orientation of the tread, either permanently or by added hinges, supposedly to help the rider flex the ankle and get weight into the heels. Other experimental improvements have included a swivel feature at the top of the leather to keep the stirrup turned out to face the rider's foot.

English-style stirrups
Stirrups used on English saddles are usually made of metal. Though called "irons," they are no longer made of iron, as a rule, but instead stainless steel is the metal of choice, due to its strength, though when weight is an issue, such as for a jockey, they may also be made of aluminum. Inexpensive stirrups may be made of nickel, which can easily bend or break and should be avoided. Stirrups may also be made of synthetic materials and various metallic alloys. There are many variations on the standard stirrup design, most claiming to either be safer in the event of a fall or to make it easier for a rider to maintain a proper foot and leg position.

Some variations include:


 * Standard iron: The most common stirrup iron, consisting of a tread, with two branches, and an eye at the top for the leather to run through. The main styles seen today include:
 * Fillis: A design with a heavy tread, and branches that rise to the eye in a rounded triangular shape.
 * Prussian: A rounder and lighter design.
 * Safety stirrups. There are a number of designs intended to release the foot more easily in the event of a fall. One style has an outside branch that  is curved, rather than straight.  Other designs feature a breakaway outer branch which will detach with sufficient pressure, freeing the foot.
 * Side-saddle stirrups: usually have a slightly larger eye to accommodate the thicker stirrup leather on a sidesaddle.
 * Other designs: have joints or hinges in the branches of the stirrups to allow for them to flex. However, one model was recalled in 2007 due to a tendency for the hinges to break. A variation on the hinged stirrup is the Icelandic Stirrup, which has the eye fixed at a 90 degree rotation to allow for less stress on the tendons, and easier retrieval should a stirrup be lost. There are a number of other patented designs with various features that are usually intended to either increase comfort or to assist proper foot position.

Western-style stirrups
The stirrup of a western saddle is more difficult to remove or replace than the English stirrup and therefore, unless damaged or a different style is desired, the same stirrups usually are kept on for the life of the saddle itself. The tread is mostly flat, but may be curved at the sides to some degree. The branches are wide at the bottom and narrow at the top, where they are joined by a heavy dowel of wood, or rod of metal. The stirrup leather loops under the rod and a "keeper," a strap with a buckle that wraps around the front and back of the stirrup leather, keeps the stirrup in place. Western stirrups are generally made of leather-covered wood, others of steel, aluminum, or even very strong fiber-reinforced plastic.

Western stirrups are designed to parallel the use intended by the design of the saddle itself; a trail riding saddle will have a wide, comfortable stirrup, a saddle for saddle bronc riding will have a narrow tread, to avoid being easily lost by the rider. A saddle for barrel racing or reining will have stirrups of a medium width, narrow enough to not be lost when a horse is moving at high speed, but with enough width to remain comfortable for a few hours. Stirrups on a saddle intended for western pleasure may be highly ornamented with silver. Stirrups on saddles used by people who use horses for hunting game in the forest are sometimes made of blaze orange for visibility to other hunters, and, because much big game hunting in the American West takes place late in the year when it is very cold, some "winter boot" designs are deliberately made extra large with an especially smooth bottom so that a person can wear heavy winter boots with a raised tread without as much risk of getting them caught up in the stirrup.

Fitting the stirrup
It is very important that the stirrup be the correct width for the boot. A stirrup that is too narrow will increase the chance that the boot will get caught in it (which would be very dangerous should the rider fall), and a too-wide stirrup makes it harder for a rider to keep it under the foot, and presents some risk that the foot might slip all the way through. It is generally suggested that the stirrup be no more than 1 inch larger than the widest part of the sole of the rider's boots.

Additionally, the rider's boot should have a heel (both English and Western-style riders).

Placement of the stirrup on the foot
In general, the stirrup is placed on the ball of the foot, allowing the rider to let his weight flow down the back of the leg into the heel by way of the flexible ankle. This provides the rider with the support of the stirrup while still allowing for him to easily absorb the shock of the horse's motion. If the stirrup is too far forward, on the toes, the rider risks losing if he pushes with too much pressure (forcing it off the foot) or too little (allowing it to simply slide off).

Some riders ride with the stirrup more "home," or shoved toward the heel. This is seen most often in sports such as polo and eventing, where the speed and sudden changes of direction of the former, and the great change in terrain and solid fences of the latter, make the rider more likely to be jarred loose from the saddle and increases the risk of losing a stirrup. However, this placement actually puts the stirrup on the arch of the foot, in a weaker position that leads to tension in the leg, stiffness in the knee and decreases the flexibility of the ankle, and therefore the shock-absorbing ability of the rider; paradoxically increasing the risk of a fall. Additionally, it increases the chance that the rider's foot will become stuck in the stirrup during a fall, a very dangerous situation. This placement is often counterproductive and should not be used if it is not an absolute necessity. The "home" position has some value in saddle bronc riding, as a lost stirrup will almost inevitably result in the rider being thrown from the bucking horse, but because riders are thrown from the horse at a high rate even under normal circumstances, this event also has a high rate of riders being hung up in their stirrups and injured in the process.

Additional sources

 * Bennett, Deb. Conquerors:  The Roots of New World Horsemanship. Amigo Publications Inc; 1st edition 1998. ISBN 0-9658533-0-6
 * John Sloan, "The stirrup controversy"
 * Medieval Technology Pages:Paul J. Gans, The great stirrup controversy"
 * Gies, Frances and Joseph. Cathedral, Forge, and Waterwheel. New York: Harper Perennial, 1994.
 * Gies, Frances and Joseph. Cathedral, Forge, and Waterwheel. New York: Harper Perennial, 1994.