Heya (sumo)

In professional sumo wrestling, a heya or beya (部屋, lit. 'room'),^[a] most commonly and metaphorically translated in English as "stable",^[1][3][4] but also known as "training quarters",^[4] or "fraternity",^[5] is an organization of wrestlers where they train and live in a "quasi-monastic and militaristic lifestyle".^[3]

Closer to a medieval fraternity than a modern sports team, a stable is a group that lives, eats, trains, sleeps and socializes together, under the authority of one or more elders.^[5] Additionally to wrestlers, all the traditional sports professionals (such as gyōji, yobidashi and tokoyama) must belong to a heya. Heya vary in size, with the largest and most successful stables having a completely different training environment from the smaller stables that have a dimension described as being more family-oriented.^[6] Most heya are based in and around the Ryōgoku district of Tokyo, sumo's traditional heartland, although the high price of land has led to some newer heya being built in other parts of Tokyo or its suburbs.^[7]

In 2004, the Japan Sumo Association recorded a record number of 55 active stables.^[8] There are currently 45 active sumo stables (as of October 2024), each of which belongs to one of five ichimon (factions or clans).^[b] These groupings of heya, each with their own history, traditionally serve to maintain the cohesion of stables linked by family ties, but also have a role to play in the struggle for influence within the Japan Sumo Association.

During the Genroku period various sumo groups concentrated from the countryside to the major cities of Edo, Osaka and Kyoto.^[10][8] These groups consisted of masterless samurai (called rōnin) who had lost their social benefits with the peace period established by the Tokugawa shogunate.^[11] Rōnin had no choice but to put their martial art skills to good use in street sumo tournaments, called tsuji-zumō (辻相撲, tsuji-sumo, lit. 'street-corner wrestling'), for the entertainment of passers-by.^[12] Similarly, a number of street entertainment wrestling groups formed and began touring, sometimes with the support of shrines that occasionally recruited them as part of religious festivities and to help priests raising money for the construction of buildings.^[13]

Gradually, the groups self-organised under the leadership of elders, who welcomed the wrestlers into their homes, which took the name of heya (meaning "fraternity house") in reference to the rooms in which these elders met to organise matches during tournaments.^[10] During this period, the term heya therefore referred to both the training institutions and the living space of the masters.^[8] The system became profitable and was quickly adopted by sumo associations in Osaka and Edo between 1757 and 1792.^[11] During the Hōreki era, masters began to inherit the names of their predecessors, and heya were gradually referred to by the name borne by the master.^[10] Nearly all of the sumo stables founded by the Edo-based sumo association were founded between 1751 and 1781.^[1] During this same period, Edo established itself as a major sumo sports center, and it was common wrestlers from other major metropolises (such as Kyoto and Osaka) to emigrate and train with the heya of the Edo-based sumo association.^[14] Although mostly founded by former wrestlers, some stables dating back to the 17th century were founded by gyōji.^[14]

During the Edo period, all wrestlers were officially attached to a stable, but a formal exception existed for wrestlers who benefited from the patronage of local lords, the latter taking the most prominent wrestlers under their wing.^[15] These wrestlers, who continued to wrestle for their stable, were however considered "borrowed" from the lords rather than officially attached to their heya, thus giving the name kakae-rikishi (抱え力士, lit. 'embraced wrestler' or 'retained wrestler') to the wrestlers and to the system.^[16]

During the Meiji Restoration and the abolition of the han system, this system came to an end and stable lost the patronage of the lords, who were forbidden to maintain households of their own.^[17] With the loss of income security and social status came a period of semi-censorship of sumo, with the adoption of Western ideology leading to the perception of sumo as unworthy of the new era, as the matches were seen as barbaric and the semi-nudity of the wrestlers shocking.^[18] With the disappearance of government protection, some stable organized themselves into fire brigades.^[19] Historically, it was possible to found a stable while still being an active wrestler. This process was allowed by the nimaikansatsu (二枚鑑札) rule, or two-license system, meaning possessing both a wrestler's and a trainer's license.^[20]

In 1943, at the turning point of the Pacific War, sumo competitions were disrupted and Tokyo became the target of intensive bombardments that destroyed many stables.^[21][22] Most of the remaining stables decided to move to the Tokyo suburbs or neighboring towns to escape the bombing.^[23] During that period, the wrestlers were either drafted into the army or navy, or incorporated into provincial work units organized by stable.^[21]

During the 1970's, the question of opening up the toshiyori title, and ultimately the creation of stables, to foreign wrestlers arose for the Japan Sumo Association, the latter declaring firstly that sumo being Japan's national sport, it was inconceivable that a foreigner could participate as a trainer.^[24] The statement was subsequently severely criticized in the press.^[25] This led the association to correct its position in this regard, with the JSA subsequently declaring that the two rising stars of foreign origin Takamiyama and Kaneshiro would indeed be eligible to become coaches within the association after their retirements.^[26] Takamiyama was the first to retire, becoming a coach under the name Azumazeki and founding Azumazeki stable, the first foreign-born sumo wrestler to do so.^[26][27] In 2003, former yokozuna Musashimaru also retired and in 2013 founded Musashigawa stable, the second stable to be founded by a wrestler of foreign origin.^[28]

Only retired wrestlers can open stables.^[29] To create a stable, they must be eligible for toshiyori status (and acquire an elder share) within the Japan Sumo Association.^[30] Only wrestlers who have reached the ranks of san'yaku (meaning yokozuna, ōzeki or sekiwake and komusubi) and have held it for at least one tournament are directly entitled to apply to remain as an executive within the association. Wrestlers who have attained the rank of maegashira must have held their status for twenty tournaments, while jūryō wrestlers must have held theirs for thirty tournaments.^[30] Technically, any retired wrestler who has secured possession of an elder share can open his own stable.^[31] There is thus a maximum potential of 105 stables within the association.^[31][32] The approval of the Japan Sumo Association is required to open one's own stable or to inherit an existing one.^[29][33] The approval is however regularly granted without much difficulty.^[33] To found the stable, a master must also ask permission from the owner of the stable to which he belongs.^[34] Furthermore, since 1976, if a foreigner wishes to remain in the Sumo Association after his retirement to acquire an elder share and found a stable, he must give up his nationality and become a Japanese citizen.^[35][36] In recent years, an increasing number of wrestlers of foreign origin have become elders and founded stables.^[8]

In general, access to the responsibility of stablemaster is a question of inheritance. A toshiyori is given full power to choose his successor as soon as a wrestler is eligible for that title by fulfilling the minimum requirements of the status.^[37] When a stablemaster dies or retires, it is usually left to an active or retired member of the stable to take over the said stable.^[34] In most cases, an oyakata will change his elder name in order to take over the reins of the stable.^[34] To do so, he must make a traditional payment to the former stablemaster in order to inherit his elder share, as well as a payment for the building and land.^[34] Since speculation on elder shares was driving up prices to the point of making them virtually unobtainable, it was not uncommon for masters to sign a contract with retiring stablemasters or their families to make monthly payments or rental fees if they were unable to provide the entire succession price at once.^[34] There are nuances in the inheritance of stables that differ slightly from the classic management of an elder share that would not be attached to the ownership of a stable. Stables are run on the basis of family relationships, and hence a stablemaster is more likely to give his stable to a relative if the latter achieve sekitori status.^[38] It is also not uncommon for former sekitori to inherit a stable from a stablemaster if they have married into the latter's family.^[34][39] For example, former yokozuna Sadanoyama secured the inheritance of Dewanoumi stable by marrying the daughter of his master, former Dewanohana, to the detriment of former yokozuna Chiyonoyama.^[34]

The other way to become a stablemaster is independance. In most cases, a stable is often founded because a master wishes to become independent of the stable to which he is attached.^[34] Often, it is because a master has little chance of inheriting his master's stable and therefore prefers to found his own.^[34] The creation of a stable is never immediate. Elders who wish to set one up usually stay with their former stable for a while as a coach, to learn how to manage it.^[40] The new stable is usually founded by taking on some of the wrestlers from the old stable.^[34] Since the foundation of a new stable is often based on the master's former stable, it is common for the new stable to maintain strong links with its original stable.^[34] However, the creation of new stables remains a marginal phenomenon, as elders often lack the financial backing to become independent.^[41] In the 1990s, rumor had it that you needed to acquire around ¥200 million to found a stable.^[40] In the early 2020s, the trend was even for stables to close and merge with one another.^[42]

A heya is always named after the toshiyori kabu (the name of the elder share) owned by its head coach. An stablemaster is obligated to retire and pass on ownership of a heya at age 65. When a new oyakata who has not inherited the retiree's elder name takes over a heya, the name of the heya is generally changed to the new owner's elder name to reflect this.^[43][44] Further oyakata may be attached to the stable.^[3]

Until 1950, the stables operated without assistance from the association. In return, the stables divided up the Japanese territory to organize tours and the donations collected went entirely to the stable.^[8]

Since 1950, stablemasters receive an additional sum with their salary every month to cover the needs of their stable.^[45] These include the cost of buying food, maintaining the building and training equipments and paying for the extra costs of training wrestlers.^[45][46] In addition to this maintenance sum, a fixed sum is paid for any wrestler in the stable who has not reached sekitori status.^[47] A so-called "incentive" sum is also paid every tournament month, meaning every two months starting in January, for each wrestler trained to sekitori status.^[47] This sum varies according to a wrestler's current rank: the higher he is in the hierarchy, the higher the sum paid to his stable master.^[47] In this system, where the big stables receive large sums of money, the distribution of funds is designed as an incentive for elders to recruit and train winning wrestlers.^[29] In the wake of the scandal, which revealed links between several wrestlers and trainers and organized crime, reforms were put in place forcing stables to publish the list of their patrons and to be able to set up only in buildings whose owners had been previously recognized by the Sumo Association, in order to increase the financial transparency of professional sumo.^[46]

Although the association gives money to the stables, they remain financially very complicated to maintain, with costs such as food purchases running into the thousands of US dollars per month.^[29][42] A saying states that a stable is only profitable when it can house ten wrestlers.^[42] Stables are therefore largely dependent on support groups. These groups of patrons, known as koenkai, began to emerge during the late and mid-Edo period in Edo and Osaka.^[47] The groups grew during the Meiji period, when nobles who had always formed wrestling groups turned away from the sport. In their place, associations of patrons were frequently formed to award prizes to wrestlers who scored well in tournaments.^[48] The first two associations among the oldest known were the hinoshita kai (日下会) and the banzai kai (万歳会), the latter not being linked to any particular stable.^[48] The practice of creating a patron's club to support famous wrestlers then developed in the early 20th century.^[49] In those days, supporting wrestlers by taking them to lunch or paying for their entertainment was considered a great extravagance.^[47] Nowadays, being seen in the company of wrestlers is still an indication of status and wealth.^[47]

Patron groups can support specific stables or wrestlers. They vary in size according to popularity.^[47] It's not unusual for koenkai to be run by powerful financiers or government officials, with a restricted and elitist group membership.^[47] Although most of the support and sums paid to the stables remain secret, some relationships are well known, such as the relationship between the old Futagoyama stable (latterly known as the former Takanohana stable) and a Buddhist sect, which is said to have contributed the equivalent of $5 million to the stable.^[50]

In the world of stables, there is no place for women with the exception of the stablemaster's wife and possibly a maid.^[51] In this highly masculine world, a Shōwa era saying held that the birth of a daughter in the midst of a heya was a source of great joy.^[52]

The wife of the stablemaster is known as the okamisan and she is expected to assist him.^[33] To do this, she is traditionally expected to abandon her career and devote herself entirely to helping her husband.^[53] She takes on the role of surrogate mother for the people attached to the stable, logically imitating the stablemaster's paternal role.^[54] Since most young recruits become wrestlers after junior high school, the emotional and physical separation from their families can be very painful, and it's the okamisan's role to comfort and advise them.^[55] In the stable, the okamisan is responsible for a wide variety of tasks. She mainly advise recruits and help with kitchen chores.^[54] She is also in charge of management, teaching, accounting and even banking, since she is often in charge of the young wrestlers savings.^[56] The okamisan also manage the public relations of the stable, whether with the wrestlers' families or the patron's organization.^[33] Okamisan play such an important role in the stables that without them many heya would find it difficult to function.^[56] In order to support each other, it's no secret that okamisan have organized a group to exchange and advise each other.^[56]

It's not unusual for the okamisan herself to be familiar with the world of stables, and some are the daughters of sumo wrestlers who have become stablemasters in their own right.^[55] A recent example included the marriage of former ōzeki Takakeishō to the daughter of former Hokuten'yū in 2020.^[52] Historically, most of stablemaster's wives came from families managing ryokan or even traditional dancers.^[52] Some okamisan were also models or actresses. For example, the wife of former Wakashimazu is the former popular singer Mizue Takada.^[52] Most unusually okamisan of Asakayama and Nishikido are also former pro-wrestler and soprano respectively.^[56]

Due to the Shinto roots of professional sumo, women do not have full freedom of movement in the stable. Their actions are subject to the same restrictions, due to traditions that consider women's bodies impure, as other professional sumo-related events. In fact, even in the stable, a woman is not allowed to move around the training area, and must remain on the observation platform next to it to converse or watch the wrestlers.^[57][58] Furthermore, unlike other traditional sumo professionals, who are all men, okamisan do not receive a salary despite their important position in the organization of the stables.^[56] Because their position is based exclusively on a marital bond, some okamisan faced with the death of their husband are required to hand over their home (the stable) to a successor of their husband and leave the building's apartments to take up other activities. This was notably the case for the wife of Asashio III who, after his sudden death, left to run a family chankonabe restaurant in Nagano prefecture.^[52]

The process of being recruited by a team is fairly straightforward, with most teams happy to publish their details and telephone number on their own website.^[59]

Since the 1970s, sumo has developed an intensive scouting system.^[60] The largest stables have established scouting networks throughout the country, partly supported with the help of their nationwide patron organizations, with retired wrestlers and patron-club members acting as part-time scouts for the stables.^[60] It is also not rare for acquaintances of the coaches or stablemaster, or one of the stable wrestlers, to also bring potential apprentices to a specific stable.^[61] When on provincial tours, masters always lookout for potential talent.^[60][61] Despite all the efforts made by masters to attract new talent, it is often the case that young wrestlers are motivated to join the stable solely by the reputation and achievements of the current master.^[62] Most of the time, the stables ask their new recruits to train for a trial period before accepting a wrestler definitively.^[59]

However, recruiting new wrestlers has become increasingly difficult. This is mainly due to low financial guarantees, as only wrestlers who have qualified as sekitori can earn a salary.^[63] The rigors of stable life, typical of the lower ranks of the hierarchy, are also an obstacle.^[63] It was also noted that stablemasters with the best links to school and university programs attracted more wrestlers, threatening the survival of stables without this type of contact.^[42]

Statistically speaking, the most populous stables in professional sumo are (as of April 2024 and in descending order), Isegahama stable, Nishonoseki stable and Kokonoe stable. Four other stables only manage to maintain a roster of more than twenty wrestlers, with Sadogatake stable and Oitekaze stable (each tied for fourth most populous stable) and Takasago stable and Kise stable.^[64] By contrast, only two sables have fewer than five wrestlers: Kataonami stable with four wrestlers (including two sekitori) and Nishikido stable with three wrestlers (including one sekitori).^[64] In terms of proportions, Kise stable and Oitekaze stable are the stables with the best ratio of sekitori to total members (six sekitori out of twenty-one wrestlers each).^[64] Isegahama stable was recognized as having the best ratio, but since the merger of Miyagino stable in March 2024, its number of wrestlers have more than doubled.^[64] Of all the active stables, twelve had no salaried wrestlers.^[65]

When registering as a wrestler, foreigners must have the support of two guarantors and a work visa.^[63][66] Foreigners who are accepted as apprentices generally find it very difficult to integrate into stable life, and more particularly to get used to the diet.^[67]

The Japan Sumo Association caps the number of foreign wrestlers who can enter a professional stable. Restrictions on the number of foreigners allowed in professional sumo began in 1992, after Ōshima stable had recruited six Mongolians at the same time.^[68] The Sumo Association's new director Dewanoumi, announced that he was considering limiting the number of foreign recruits per stable and to cap it at the level of the entire association. The decision remained informal, but foreign recruitment ceased for a period of around six years.^[69] Dewanoumi's decision was later overturned, with the formalization that a limit of only two foreign wrestlers could belong to the same stable. At association level, the total number of foreign wrestlers was set at forty.^[69]

Then in 2002, a one foreigner per stable policy was officially adopted, though the ban was not retroactive, so foreigners recruited before the changes were unaffected. The move has been met with criticism, not least because Japanese culture, with its centuries-old and xenophobic culture, is accustomed to treating foreign wrestlers as gaijin (外人, lit. 'outsiders' or 'aliens'), regardless of their place of birth, reinforcing the difference that the public and the media make between foreign and Japanese wrestlers.^[35][69][70] Paradoxically, all wrestlers involved in professional sumo are formally treated the same once they have joined the stables, and no distinction is clearly made as to any special treatment for foreigners.^[70] John Gunning also proposed another interpretation of the decision, claiming that this rule was not based on racist sentiment but to ensure that foreign rikishi assimilate into sumo culture.^[71] He explained, there would be ten Hawaiian wrestlers in the same stable living in their own "little clique," not learning Japanese, so the rule "protects the culture of stables."^[71]

Originally, it was possible for a place in a stable to open up if a foreign born wrestler acquired Japanese citizenship. This occurred when Hisanoumi changed his nationality from Tongan at the end of 2006, allowing another Tongan to enter his stable.^[72] However, on 23 February 2010 the Sumo Association announced that it had changed its definition of "foreign" to "foreign-born" ('gaikoku shusshin'), meaning that even naturalized Japanese citizens will be considered foreigners if they were born outside of Japan. The restriction on one foreign wrestler per stable was also reconfirmed.^[73] This change in policy was also attributed to the actions of former yokozuna Asashōryū, which fueled a growing anti-foreigner feeling within the Sumo Association.^[74] As Japanese law does not recognize subcategories of Japanese citizen, it was pointed out that this unique treatment of naturalized citizens may be illegal under Japanese law.^[75]

Since stable members live in a brotherhood similar to a family, they are forbidden to fight another member of their stable during tournaments.^[76][77] This rule was not always the norm and during the Edo period, stablemates could compete against each other.^[8] The current rule was introduced in particular because of the fear that wrestlers who share the same training, coaches, hobbies and meals would give in to the temptation of wanting to help a stablemate.^[76] Since stables are generally created by transferring wrestlers from an original stable, match-ups between wrestlers who used to belong to the same stable are also avoided as much as possible.^[34][76] A special rule nonetheless dictates that wrestlers from the same heya can fight each other in a playoff situation for a yūshō or divisional championship.^[78][77] Since wrestlers don't compete directly with each other, this system encourages a sense of unity and loyalty between members of a given stable.^[54]

This non-confrontation rule is known to create feelings of frustration shared by stables that don't have several top-ranked wrestlers.^[79] For example, the rule worked to the advantages of Futagoyama stable's Takanohana, Wakanohana and Takanonami, during the 1994–2000 period, as they never had to fight each other when all three were at the top of the ranking, either ranked at ōzeki or yokozuna.^[80] In addition, during Futagoyama's pinnacle, these wrestlers could do without facing five other wrestlers on the makuuchi roster with the presence of Akinoshima, Takatōriki, Misugisato, Takamisugi and Wakashoyo during the 1992–1995 period.^[79] During the same period of time, however, Yokozuna Akebono had to face all the wrestlers in the same division.^[79] Since Akebono and Wakanohana had close matches, when the latter won against the former it was common to say that Wakanohana provided suppressive fire (援護射撃, engoshageki) for his brother Takanohana, who was often in the title race with his rival Akebono.^[79]

Recent examples also include Takayasu's promotion to the rank of ōzeki while stablemate Kisenosato was yokozuna or when Terunofuji was also ranked at ōzeki while stablemate Harumafuji was also yokozuna.^[79] During the same period of the duo Kisenosato-Takayasu and Harumafuji-Terunofuji, ōzeki Gōeidō and both yokozuna Kakuryū and Hakuhō were to face most makuuchi wrestlers.^[79]

Generally speaking, professional sumo does not allow a wrestler who has decided to retire to return to the sport.^[59] Furthermore, there are no player trades in professional sumo. When a wrestler begins his career in a stable, he is expected to stay there until he retires.^[81] Rare exceptions are if the coach who originally scouted him leaves to found a new heya, in which case he might be permitted to follow him, or if a heya shuts down due to retirement or death of the stablemaster, mismanagement or financial reasons, the remaining wrestlers are often permitted to transfer to another heya, usually within the same ichimon.^[82]

Unofficially, however, discontent can lead to wrestlers leaving their stables. This was particularly true of Shikihide stable in 2020, where, to show their dissatisfaction with the okamisan's management methods, half of the stable's wrestlers fled and went to the Sumo Association for help, complaining about her strict behavior and invasions of their privacy.^[83]

Active wrestlers and masters are not the only members of the Japan Sumo Association to be attached to the stables. All the traditional professions affiliated with the association are attached to the stable system.^[80]

Wrestlers who have not attained the prerequisites to become a master or who have not been able to secure possession of an elder share may remain with their stable. Their tasks are to supervise the young wrestlers and manage minor jobs for the association. They essentially become contract employees, customarily retaining their old shikona as their professional name. They are separated into two distinct roles: wakaimonogashira (若者頭) and sewanin (世話人). Wakaimonogashira, or "youth leaders", serve as officials of the association. They typically work at their former stables or within the associated ichimon. Wakaimonogashira are tasked with arranging maezumō matches and supervising young sumo wrestlers from makushita and below. They also appear in public next to the dohyō during the honbasho closing ceremony, receiving the trophies given to the tournament winner to return them backstage. There is a maximum of eight wakaimonogashira within the Japan Sumo Association.^[84][85] Sewanin, or "caretakers", work as transportation and storage managers, handling association equipment used for tournaments and regional tours. In addition they deal with miscellaneous, primarily physical tasks. They are instructed by the master of the stable they belong to, or other association members (including wakaimonogashira). There can be only thirteen sewanin within the Japan Sumo Association.^[84][86]

In addition to the former wrestlers, the stables also host gyōji (referee) and yobidashi (handymen).^[87] Both groups are involved in the management of their stables during the periods between tournaments, and it is not uncommon for referees to be entrusted with clerical work.^[88] Tokoyama (hairdressers) are also affiliated to the stables.^[89] Stables that do not have their own tokoyama can rely on hairdressers from other stables belonging to the same ichimon (clan) to do their wrestlers' hair.^[89][90] If a tokoyama's stable doesn't have a more experienced hairdresser, a hairdresser from the same ichimon will take over the apprenticeship.^[91]

The entrance to a stable is often marked by a calligraphic wooden nameplate.^[81] Some of them are carefully written by famous caligraphers.^[92] Most signs are installed vertically, but some are also installed horizontally.^[93] Stables have a great deal of freedom in the signs they choose to install: the Arashio stable's sign was calligraphed to depict a cliffside landscape facing the sea,^[94] while the Miyagino stable's sign made the unconventional choice of applying gold leaf to the name, at a total cost of ¥2 million.^[95]

Each stable features the same basic layouts,^[96][97] with common rooms that can be used as dormitories, a dining area, communal baths and a training room equiped with a dohyō (called keikoba).^[5][98] Next to it, a wooden or tatami platform is set up so that masters can watch training more comfortably and visitors can observe the training session.^[99][100] The stablemaster lives in his stable, with his quarters on the upper floors. He lives there with his family in an apartment better furnished than the rest of the building.^[53] In the common room, personal storage is usually nothing more than a plastic container.^[96]

An emblematic feature of stables, the keikoba is often located on the first floor, next to the entrance.^[96][100] This particularity is often a challenge for architects who work on the construction of stable buildings because this land is considered sacred ground and no one is supposed to walk or sleep above it.^[32] Some stables have therefore decided to install their training ring on the top floor.^[32] The floor of the training room is entirely covered with earth, and the walls are often clad with wooden planks, installed to absorb the shock of wrestlers who are pushed against the walls during training.^[53] In the corners of the room are often teppō, wooden poles for practicing striking.^[100] The training room is often equipped with several windows for ventilation, as most stables do not have air conditioning or heating installed in this room.^[100] Since the floor is considered sacred ground, a kamidana (a small Shinto altar) is often hung on the wall.^[100] Stables traditionally display their members' names and rankings on the wall of their training room. This is done using calligraphic wooden plaques.^[100] Some stables decide not to imitate competition rings in order to minimize the risk of injury by removing straw limits, while others install several training dohyō to allow several apprentices to train at the same time.^[32]

Until the end of the 1960s, a large number of stables were still housed in buildings in a dilapidated state. During the 1970s, many stables began to undertake renovation work, aided by the success of their star wrestlers (such as Taihō for Nishonoseki stable and Takamiyama for Takasago stable).^[32] As financing a new stable building is expensive, it's not uncommon for newly-independent stablemasters to take up temporary residence in unsuitable buildings before moving again. Onoe stable, for example, converted a narrow garage into a training room.^[101] Another method of obtaining a suitable building is to reuse the building of a stable that has previously moved, as was the case for Musashigawa stable, which currently occupies the premises of the now-defunct Nakamura stable.^[101]

Most of the stables are located in the district of Ryōgoku of Sumida, Tokyo.^[96] Historically, this installation is due to the decision of the Edo authorities to maintain two tournaments per year at the Ekō-in temple, located in this district.^[8] Within Ryōgoku, a good half of the stables are located less than two kilometers from the Ryōgoku Kokugikan.^[96] Even during the period when the association's headquarters were relocated to the Kuramae neighborhood (in Taitō) with the Kuramae Kokugikan, no stable made the choice to move out of the Ryōgoku district.^[102] However, some stables choose to relocate, in particular under the impetus of districts wishing to revitalize their neighborhoods by setting up a sumo institution, which is usually a popular tourist spot.^[96] In the 2020s, several stables have chosen to relocate in the neighbourhoods of Shibamata (Katsushika), Hashiba (Taitō) and Rokuchō (Adachi).^[103]

When the stables have to travel outside Tokyo for the year's three outdoor tournaments, they often set up in shrine grounds.^[80] This is because the ancestral links between professional sumo, which used to organize charity tournaments for temples and shrines, are being maintained.^[104] For example, Tatsunami stable is known for being hosted at the Sumiyoshi-taisha during the Osaka tournament,^[104] and Miyagino stable at Nanzo-in during the Kyushu tournament.^[105] In recent years, however, more and more stables have opted for community centers.^[106] The decision to relocate accommodation is often due to requests from sanctuaries who, in accommodating the large stables, often notice damage to temple precincts and buildings.^[107] These installations in community centers also raise a number of questions, not least because some municipalities, particularly interested in the presence of wrestlers, often offer a large number of lodgings, some of which are also dedicated to emergency accommodation in the event of natural disasters.^[106]

For residents of the communities where the stables are located, it's also an opportunity to take part in activities designed to strengthen ties between residents and wrestlers.^{[106][107][108]} During the local tournaments, the relative independence of married wrestlers comes to an end, as they are obliged to stay with the rest of the wrestlers in the dormitory.^[80]

During the scandal surrounding the links between certain stables and organized crime, it was revealed after investigation that several stables had used a criminal network to find land on which to settle, such as Sakaigawa stable for the Nagoya tournament or Matsugane stable for the Osaka tournament.^[109]

Life in a stable is organized on the basis of a social structure similar to that of a family home and a paramilitary organization.^[110] Stable management is above all autocratic and incorporates elements of communal life.^[2] Most wrestlers, and all junior-ranked ones, live in their stable in a dormitory style: training, cleaning, eating, sleeping and socializing together.^[111] At the top of the social pyramid, the shishō (師匠, stablemaster) takes on a paternal role.^[5][54] Of all the coaches potentially present in the stable, he alone is the owner of the stable and therefore the highest authority in communal life.^[112]

The treatment a wrestler receives in his stable is based exclusively on his ranking.^[90] Upon joining the stable, a young recruit is assigned to a more experienced wrestler. In theory, this mentoring by a senior wrestler is encouraged so that a newcomer is familiar with the codes of stable life. In practice, however, recruits become responsible for so many chores that they can be considered "personal slaves".^[54] At the very top of the active wrestlers is the heya-gashira, the highest-ranked wrestler in his stable.^[5]

The cornerstone of stable life is training (often early in the morning).^[79] Wrestlers ranked in the lower divisions get up at dawn (usually around four or five) to do morning chores around the building and stretch in preparation for the usual empty stomach morning training.^[113][114] Just before the training session, the day's lunch team begin their preparations.^[113] The morning exercises done by the wrestlers are designed to exhaust wrestlers and strengthen their fighting spirit, and are repeated every morning without exception.^[115] Gradually by rank, the wrestlers join in the training and the stablemaster only appears once the sandanme wrestlers have started training.^[113] Sekitori-ranked wrestlers always turn up last at training sessions, often around eight o'clock, and their assistants have to temporarily leave the training to help them put on their mawashi.^[114][115] On arrival at the training hall, sekitori are systematically greeted by wrestlers of lower rank than themselves.^[115]

When the sekitori practice is at its height, the stable cooks begin to prepare the first and major meal of the day (usually chankonabe).^[116] The chankoban (ちゃんこ番), meaning being responsible for preparing the meal, is a rotating task that includes shopping the day before, preparing the meal and making sure the kitchen is clean after use.^[117] In most stables the cooking brigade is supervised by one of the oldest and most experienced of the low-ranking wrestler, the chanko-cho,^[118] often affectionately referred to as ojii-chan (おじいちゃん, lit. 'grandpa').^[116] Although chankonabe recipes have been homogenized, each stable is known for a its specific recipe, each with its own ingredients and flavors.^[119] Around eleven, the wrestlers all head for the baths-in descending order of rank, so that the sekitori always benefit from a clean bathroom.^[116] Wrestlers eat by turns according to rank.^[120] The sekitori are served by makushita wrestlers, who are in turn served by sandamme wrestlers, and so on down to the youngest apprentices.^[120] The lowest ranks, who were up and working before anyone else, must patiently and hungrily wait until all of the others have finished and gone upstairs to have a siesta-like nap.^[120] Within the stable, only wrestlers who have qualified as sekitori have the right to a private room, with the rest of the wrestlers sleeping in a dormitory-like communal room.^[113] Since the vast majority of wrestlers live in this room, it often lacks space and can only accommodate a futon and a few personal belongings.^[5] Even the sekitori's private rooms can seem small by Western standards.^[5] Wrestlers who have obtained the right to marry may move out of the stable to live with their spouse.^[81]

During the COVID-19 outbreak, sumo stables were particularly closely monitored because of their communal living system, which is particularly conducive to the development of the virus.^[121]

During the afternoon hours, the non-sekitori wrestlers often take on other tasks, such as cleaning the entire stable and the baths, emptying the garbage cans or doing the laundry and drying the used mawashi.^[122] After these chores, it is not unusual for a stable to be perfectly silent.^[120] Afternoon periods are generally devoted to relations with support organizations and fan clubs, hobbies, or taking care of a family, if a wrestler has obtained the right to marry.^[120]

On the evening of the end of a tournament, the stables organize an uchiage, a party including all stable members and patron groups.^[123]

In the 1970s, the testosterone-rich environment of the stables created a number of problems, including frequent police interventions for public drunkenness, disorderly conduct, brawling and inappropriate behavior towards women.^[52] Recently, however, changes in Japanese society have softened the young recruits, who are now much calmer. It's even widely accepted that the disciplinary regime required by the Sumo Association for its stables is now much stricter than in the rest of Japanese society.^[52] In recent years, the stable system has been gradually reinventing itself.^[124] These changes are partly attributable to changes in the way spectators view wrestlers.^[52]

The new developments involve changes to the traditional hierarchical structure of the stables and in the tasks performed by each individual. It is no longer unusual to see food advisors (like in Nishonoseki stable) or professional cooks (Hidenoyama stable) operating to enable better dietary monitoring of wrestlers.^[125][126] As early as the 1990s, stablemasters and okamisan also began to take part in housekeeping and cooking activities, whereas in previous decades these tasks had been assigned exclusively to low-ranking wrestlers.^[52] It's also interesting to note that some stablemasters now do sport-related degrees before opening their own stable, such as the former Kisenosato (Waseda University) and Kotoōshū (Nippon Sport Science University).^[127][128]

Many stablemasters now arrange the buildings of their stables in a less traditional way, in order to make life easier for their wrestlers.^[97] These new developments can sometimes be taken to extremes, as with Asahiyama stable, which, with a view to asserting itself as a community center, founded back-to-back an animal shelter and a bakery in 2021.^[129][130] For its part, Oshiogawa stable opted for an apartment complex (the Creative House Bunka) mixing rental apartments with stable quarters. The initiative was taken to strengthen social ties in the neighborhood, and Oshiogawa stable provides access to morning training sessions and organizes chanko dinners for residents and photo sessions with babies.^[131]

It is becoming increasingly common for stables to be involved in partnerships and cooperation agreements. These partnerships often aim to cooperate further in a wide range of areas, including tourism, culture, sports, and educational promotion, and work closely to revitalize local communities. This was particularly the case for Ōshima stable, Kokonoe stable and Futagoyama stable that signed a partnership and cooperation agreement with the Katsushika Ward of Tokyo.^[132]

In contrast to the secretive reputation of professional sumo, it has become common practice for stables to welcome visitors to watch training sessions.^[133] Spectators can attend free of charge, although rules vary from stable to stable, as to the size of the group and whether advance notice or a Japanese speaker are required.^[134]

In addition to occasional visitors, the stables regularly welcome elementary and junior high students during the summer vacations as part of the "Open sumo stable" program organized by the Sumo Association.^[135]

As in other traditional disciplines such as Noh or Shogi, where players belong to schools which in turn belong to larger groups of traditions, heya belong to groups formed throughout the history of sumo.^[136] In professional sumo, these groups are called ichimon (一門, lit. 'clan' or 'family'), a grouping of stables in which each stable must be affiliated.^[41] Because of their specific nature, clans are also sometimes referred to as the sports equivalent of a traditional family or a commonwealths.^[137][138]

Each ichimon answers to its honke, its mother house, which is the stable whose name is used to designate the entire clan.^[137][139] The clan's other stables are referred to as bunke (branches),^[137] and the relationship between them and the mother stable is called dōmon (同門, "studying under a same teacher").^[140] If an elder decides to set up his own stable and he and his former master part on good terms, his stable will be part of the same group as his original stable.^[138] The organization of the clan system is particularly important within the Japan Sumo Association, as its balance determines the positions of directors and the balance of power within the board of directors ahead of the elections.^[141]

Following the Takanoiwa affair and the dissolution of the Takanohana ichimon in 2018, the total number of clans in the Sumo Association was fixed to five and it was made mandatory for all stables to choose which clan to join, putting an end to the loose system and the autonomy of stables in their choice of alignments.^{[139][142][143]}

Of the five current clans, not all enjoy the same aura or influence within the association. For example, the Dewanoumi and Nishonoseki clans each have more influence than the three smallest clans (Tokitsukaze, Isegahama and Takasago) combined.^[144] The powers of the various clans have also evolved with the association itself.

Although the term ichimon did not appeared until the Shōwa era,^[145] the system itself dates back to the Edo period.^[146] Originally, ichimons were called kumiai (組合, union), with the meaning of an "itinerant group".^[136][145] Before the Shōwa era, the operation of professional sumo revolved around these independant groups under the patronage of the sumo association.^[146] Without earned wages, wrestlers belonging to the stables of a particular union were largely dependent on the income from tours organized by the said union. These tours were organized by the unions themselves, and there was no association-wide tour system.^[145] In those days, the clan chief distributed the winnings from the tours to the stables according to their contribution.^[147] At the start of the Meiji era, professional sumo went through a period of disfavor and many stables continued to exist without having the means to invest in training grounds. The system of grouping into clans allowed these stables to mutualize training possibilities.^[8] In 1909, out of forty-seven stables, only eleven had a training ground.^[8]

The clan system became even more important at the end of the Taishō era. At the time, professional sumo was shaken by social movements and the tournament system, where wrestlers competed according to banzuke (sumo ranking sheet) divisions (east or west) and were forbidden to face wrestlers from the same division, offered little diversity in the matches.^[148] In 1932, the last major wrestlers' strike in history broke out with the Shunjuen Incident. That movement called for fundamental reform within the newly created Japan Sumo Association.^[149] Following the resignation of a significant number of wrestlers, the association acceded to a number of their demands and created the clan competition system, allowing more wrestlers to compete against each other in matches, the only restriction being that wrestlers from the same clan couldn't compete against each other.^[148] However, this system favoured the largest clans.^[138] Following political pressure to reform the association in 1957, the clan competition system was abolished to introduce a round-robin tournament system then replaced by the current system, based on stables, that was adopted in 1965.^[145] Because of the traditional construction of professional sumo, the clan system was able to survive because the modern factions had been built on the basis of personal relationships between the masters and the students.^[146]

In the past, the clans were close-knit, but this bond has weakened with time and the reforms of professional sumo. Nowadays clans serve primarily as political factions.^[139] Elders' ambition has also caused some clans to splinter, turning a cohesive landscape into a fragmented one.^[137] Of the clans founded during the Edo period, none remain today.^[150]

The Dewanoumi ichimon (出羽海一門), known as a conservative movement in professional sumo,^[151] also enjoys a reputation as a pillar of the association's history.^[146] The clan is the second oldest in professional sumo.^[150] In its history, six of the twelve chairmen from the wrestlers' ranks came from this clan. The ichimon also produced the most yokozuna in the sport's history, with nine wrestlers.^[8][151]

Led by prominent figures in the sport such as former yokozuna Hitachiyama, this clan had a policy of centralization, not allowing any oyakata to become independent of the stable until Tochigiyama's independence in 1925.^[146] This policy came to an end in 1981, when the former Mienoumi established Musashigawa stable. He became the first oyakata to become independent of Dewanoumi stable in 14 years, the first since the expulsion of Kokonoe (former yokozuna Chiyonoyama) in 1967 and the first to do so in a friendly manner in 56 years since Tochigiyama.^[150][152] At its peak in 1931, an entire section of the banzuke was occupied by wrestlers of the clan during the spring and summer tournaments.^[151]

The Nishonoseki ichimon (二所ノ関一門), also sometimes called the Nishonoseki-Futagoyama clan,^[141] was founded just before World War II by Yokozuna Tamanishiki.^[153] Initially, the Nishonoseki stable was part of the larger Tomozuna clan led by the eponymous stable [ja]. The Nishonoseki stable was led by former sekiwake Kaizan Tarō II [ja], who recruited Tamanishiki. The former Kaizan died in 1931, and Tamanishiki took over his name and rebuilt his stable in 1935.^[154] When the clan was created, its unofficial aim was to challenge the supremacy of the Dewanoumi ichimon.^[155] In the immediate post-war period, his successor, the former sekiwake Tamanoumi Umekichi [ja], launched a policy of clan expansion by encouraging independence. This had the direct consequence of the independence of Kotonishiki (Sadogatake stable) and Ōnoumi (Hanakago stable).^[156] Since this policy was continued by subsequent generations of Nishonoseki, the Nishonoseki ichimon is today the clan with the largest number of stables.^[9]

After the initial post-war period, the clan continued to gain influence,^[157] while being led by then-young figures like yokozuna Taihō, Tamanoumi, Wakanohana I, Wajima and Kotozakura I.^[155] Due to the clan's expansion policy, their unity is considered weak and this situation created many problems, notably in 1975 when Oshiogawa stable was founded following the dissatisfaction of former ōzeki Daikirin (which led to the retirement of top-ranker Tenryū) and also when Takanohana stable became independent in January 2010.^[146] Although still influential on the Sumo Association board of directors, the clan stagnated in recent years. One of the reasons given was that no main houshold stablemaster had previously held the rank of yokozuna since Tamanishiki's retirement in 1938. This lack of clan leader sporting influence came to an end when Kisenosato assumed the Nishonoseki elder name in December 2021.^[144]

The Tokitsukaze ichimon (時津風一門) is also an influential clan, thanks in part to former yokozuna Futabayama. The latter was a wrestler for Tatsunami stable and decided to become independent by launching his own dojo in 1941.^[158] Thanks to Futabayama's good relations with other wrestlers, his stable grew in numbers by merging other smaller stables (notably the Kumegawa stable of former ōzeki Kagamiiwa).^[158] The clan was later strengthened by the incorporation of the Izutsu stable, which had a long tradition, and Isenoumi stable, which until its integration into the Tokitsukaze ichimon led its own clan.^[146][159] Thanks to their growing number, the Tokitsukaze faction was soon able to become independent of the Tatsunami ichimon to which the main stable belonged.^[158] After Futabayama, the clan continued to grow in influence, thanks in particular to Yutakayama Katsuo. He maintained strong links with his alma mater, the Tokyo University of Agriculture, and many of the clan's recruits still come from this university.^[146]

In recent years, the clan's fortunes have been changing. In particular, the clan was publicly criticized after the Tokitsukaze stable hazing scandal.^[159] In December 2016, based on persistent disagreements between the masters of the two stables, the Oitekaze stable switched clans and left the Isegahama ichimon to join the Tokitsukaze clan. This decision was based on the long-standing ties between the Tatsunami ichimon (the former name of the Isegahama clan) and the Tokitsukaze ichimon, whose founder Futabayama himself came from Tatsunami stable.^[160]

Because of its size, the clan frequently collaborates with the Takasago ichimon to form alliances of interest.^[161]

Although the Takasago ichimon (髙砂一門), sometimes referred as the Takasago-Kokonoe clan,^[141] is the oldest of all the existing clans, it is also the smallest.^[150] The clan's origins lie in the discontent of wrestlers in the early Meiji period. One of them, Takasago Uragorō, launched protest movements before leading his own troupe independent of the Tokyo-based sumo association: the Takasago Kaisei-Gumi (高砂改正組).^[162][163] In the 1880s, the group reattached to Tokyo and Takasago emerged as a major figure in the association, being elected director in 1883.^[164][165]

The clan seems to be losing momentum with the lack of iconic wrestlers in recent years, despite a large part of the clan's influence being due to Kokonoe stable and to the emblematic wrestler Chiyonofuji and the wrestlers he raised.^[146] Chiyonofuji himself, however, never rose to the rank of chairman of the Sumo Association despite his sporting achievements, one of the reasons given being his membership of a weak clan and a certain arrogance in his dealings with the other elders.^[144] Because of its size, the clan frequently collaborates with the Tokitsukaze ichimon to form alliances of interest.^[161]

In 2020, the former Asasekiryū took charge of Takasago stable and became the first foreign-born wrestler to head an ichimon in professional sumo history.^[166]

The Isegahama ichimon (伊勢ヶ濱一門) is one of the smallest and lacks influence, notably because its stables had few links with each other before the clan was founded.^[146] The clan's complex history is reflected in its name, which has changed as the balance of influence within the ichimon shifted. The clan's history dates back to the Taishō era when former komusubi Midorishima [ja] founded the Tatsunami stable in 1915. This stable was part of the Tomozuna ichimon, from which the Nishonoseki ichimon also descended. As more stables were incorporated into the Tatsunami stable and through its alliance with the Isegahama stable, the clan was able to expand under the name of Tatsunami-Isegahama union (立浪-伊勢ヶ濱連合).^[167] When the original Isegahama stable closed in February 2007, the clan was renamed for the first time as Tatsunami ichimon (立浪一門).^[167] In May 2012, the Tatsunami stable left its own clan to join the newly created Takanohana ichimon. As a result, the clan decided to change its name to Kasugayama-Isegahama union (春日山-伊勢ケ浜連合).^[168] Finally, in November of the same year, the clan changed its name to Isegahama ichimon after the affair and resignation of the former Kasugayama stablemaster (the former Kasugafuji).^[169]

The ichimon owed the basis of its influence to the golden age of the Dewanoumi ichimon, when the latter dominated competitions with both yokozuna Tsunenohana and Tochigiyama. The Isegahama ichimon managed to stand out under the impetus of former sekiwake Kiyosegawa [ja] and Hatasegawa [ja].^[170]

The Isegahama clan is the only one to have never acceded to the association's chairmanship.^[171] Because of his sporting achievements, former yokozuna Hakuhō was long considered by public opinion to be a prime candidate for the association's highest office, but following Hokuseihō's scandal and retirement his position was considered compromised.^[171]

There was a multitude of clans in the past, some of them having been dismanteled. Before 2018, it was possible for stables to form loose coalitions or not to align themselves with a particular clan and remain independent.^[139]

The Tomozuna ichimon (友綱一門) was the major clan of the mid-Meiji era. The Tomozuna clan has its origins in the decline of the Tamagaki ichimon (玉垣一門), that clan having raised important wrestlers, such as Umegatani I.^[172] At the heart of the clan was the eponymous stable, founded by former maegashira Kaizan Tarō I [ja] when the latter became independent of the Tamagaki stable [ja]. The clan could count on the support of Itagaki Taisuke, who became a major patron of the stable.^[173] The clan quickly gained influence, thanks in particular to the trio Tachiyama, Kunimiyama and Yahatayama.^[174] From this clan came the ichimon of Nishonoseki and Isegahama (then founded by Tatsunami stable). Tatsunami was founded by Komusubi Midorishima in 1915 and Nishonoseki was founded by Yokozuna Tamanishiki in 1935.^[174]

Another example of a historic clan is the recently disbanded Takanohana ichimon (貴ノ花一門). After retiring from the ring in 2003, Yokozuna Takanohana inherited Futagoyama stable from his father, the former Takanohana Kenshi. On the strength of his great popularity, he stood for election as director of the Sumo Association in 2010. This was an unusual candidacy, as it is traditional to discuss candidacies within one's clan before standing. Takanohana left his clan, the Nishonoseki ichimon, because it had decided to nominate other candidates. This unprecedented event was later called the Takanoran (貴の乱, Taka's rebellion).^[150] Takanohana was elected director of the association,^[175] and the stables that had supported his candidacy joined his faction, which became independent of the Nishonoseki ichimon after the exclusion of stables from this group (Ōnomatsu stable, Ōtake stable, Magaki stable) that had voted in contradiction to the clan's plans. A fourth stable (Tatsunami stable) joined the Takanohana faction in 2012 and in May 2014 the independent group was officially recognised as an ichimon, because, according to the association's statutes, there was no difference in the amount of money to be paid to the Takanohana group that could differentiate it from a fully-fledged clan.^[176] After the Takanoiwa affair, the clan began to distance itself from Takanohana.^[175][177] Takanohana disbanded his ichimon in 2018 after a failed director election.^[178][179]

Immediately after the dissolution of the Takanohana ichimon, Ōnomatsu stable took over the leadership of the group from the remaining stables formerly affiliated with Takanohana (the Tatsunami and Chiganoura stables had already separated from the clan).^[180][181] The newly formed Ōnomatsu group (阿武松グループ) was short-lived and the group disbanded in November 2018, with all the stables that showed support for Takanohana joining the Nishonoseki ichimon, with the exception of Tatsunami, which joined the Dewanoumi ichimon.^[143][182]

The ichimon are encouraged to support each other.^[41] This support is shown above all during training sessions, with the clans regularly organising and taking part in joint training sessions. These sessions, called degeiko (出稽古) offer wrestlers (and mainly sekitori) a chance for more rewarding training by expanding the number of wrestlers they can train with.^[183] Each clan has its own way of doing things. For example, it is customary for the Nishonoseki ichimon to organise six joint training sessions a year.^[136] Within the Dewanoumi ichimon, it is often the Dewanoumi and Kasugano stables that meet in preparation for the January tournament.^[136]

Outside of training sessions, members of an ichimon are expected to attend the wedding and funeral of a member of the same clan. Similarly, when a promotion is announced, it is customary for members of a clan to attend to congratulate the promoted wrestler.^[136] At the end of a tournament, it is customary for the winner to be accompanied in the parade out of the arena by a wrestler from his ichimon, who acts as flag-bearer.^[175] After a wrestler is promoted to the rank of yokozuna, it is traditional for the ceremony to create his tsuna (sacred rope belt) to be organized by his stable and those of his ichimon.^[184] It is also customary for a yokozuna to perform his ring-entering ceremony accompanied by a tsuyuharai and a tachimochi from his clan.^[136]

However, the most visible part of the support shown by the ichimon is political, with the association's chairman elected every two years.^[141] The ichimon serves as quasi-political groupings, each clan nominating candidates for the ten positions or so that are available on the association's board each election cycle.^[139] Each vote is normally along the interests of the ichimon, which explain why the bigger clans more often holds the association's chairmanship.^[137][185] Former wrestler popularity however plays a role in the credit given to an application. For example, former yokozuna Takanohana won four straight election bids to become director before his demotion in 2018, despite being the leader of a (now dissolved) small ichimon.^[186]

The ichimon also plays a role in the appointment of shimpan (judges) who can question the decision made by the referees during matches, each clan having a number of judges reserved for it in this department of the association, which has only twenty members.^[102]

• Glossary of sumo terms
• List of sumo stables - a list of active heya.
• List of sumo elders
• Japan Sumo Association
• Toshiyori
• Gyōji
• Yobidashi
• Tokoyama

• Buckingham, Dorothea M. (1994). The Essential Guide to Sumo. Bess Press. ISBN 1880188805.
• Cuyler, Patricia Lee (1979). Sumo: From rite to sport. New York: Weatherhill. ISBN 9780834801455.
• Hall, Mina (1997). The Big Book of Sumo: History, Practice, Ritual, Fight. Stone Bridge Press. ISBN 978-1-880656-28-0.
• Kakuma, Tsutomu (1993). Sumo watching. Yohan Publications. ISBN 4896842367.
• Kenrick, Douglas M. (1969). The Book of Sumo: Sport, Spectacle, and Ritual. New York: Weatherhill. ISBN 083480039X.
• Newton, Clyde; Toff, Gerald J. (2000). Dynamic sumo. Kodansha International. ISBN 4770025084.
• Schilling, Mark (1994). Sumo: a fan's guide. Japan Times. ISBN 4789007251.
• Sharnoff, Lora (1993). Grand Sumo:The Living Sport and Tradition. New York: Weatherhill. ISBN 0-8348-0283-X.
• West, Mark D. (1997). "Legal Rules and Social Norms in Japan's Secret World of Sumo". The Journal of Legal Studies. 26 (1). The University of Chicago Press: 165–201. doi:10.1086/467992. JSTOR 10.1086/467992.

• The dictionary definition of heya at Wiktionary
• List of active stables at Japan Sumo Association homepage