|Country of origin||Japan|
Sumo (相撲 sumō ) is a competitive full-contact wrestling sport where a rikishi (wrestler) attempts to force another wrestler out of a circular ring (dohyō) or to touch the ground with anything other than the soles of the feet. The sport originated in Japan, the only country where it is practiced professionally. It is generally considered to be a gendai budō (a modern Japanese martial art), though this definition is misleading as the sport has a history spanning many centuries. Many ancient traditions have been preserved in sumo, and even today the sport includes many ritual elements, such as the use of salt purification, from the days when sumo was used in the Shinto religion. Life as a wrestler is highly regimented, with rules laid down by the Sumo Association. Most sumo wrestlers are required to live in communal "sumo training stables" known in Japanese as heya where all aspects of their daily lives—from meals to their manner of dress—are dictated by strict tradition.
In recent years, a number of high-profile controversies and scandals have rocked the sumo world, with a concomitant effect on its reputation and ticket sales. It has also greatly impacted the sport's ability to attract new recruits.1
- 1 Origins
- 2 Winning a sumo bout
- 3 The wrestling ring (dohyō)
- 4 Professional sumo
- 5 Professional sumo tournaments
- 6 Life as a professional sumo wrestler
- 7 Salary and payment
- 8 Amateur sumo
- 9 See also
- 10 References
- 11 Further reading
- 12 External links
In addition to its use as a trial of strength in combat, sumo has also been associated with Shinto ritual, and even certain shrines carry out forms of ritual dance where a human is said to wrestle with a kami (a Shinto divine spirit); see Shinto origins of sumo. It was an important ritual at the imperial court. Representatives of each province were ordered to attend the contest at the court and fight. They were required to pay for their travels themselves. The contest was known as sumai no sechie, or "sumai party."
Cross-influence from other nations adjacent to Japan, sharing many cultural traditions, cannot be ruled out, as they also feature styles of traditional wrestling that bear resemblance to sumo. Notable examples include Mongolian wrestling, Chinese Shuai jiao (摔角), and Korean Ssireum.
Over the rest of Japanese recorded history, sumo's popularity has changed according to the whims of its rulers and the need for its use as a training tool in periods of civil strife. The form of wrestling combat probably changed gradually into one where the main aim in victory was to throw one's opponent. The concept of pushing one's opponent out of a defined area came some time later.
Also, it is believed that a ring, defined as something other than simply the area given to the wrestlers by spectators, came into being in the 16th century as a result of a tournament organized by the then principal warlord in Japan, Oda Nobunaga. At this point wrestlers would wear loose loincloths, rather than the much stiffer mawashi wrestling belts of today. During the Edo period, wrestlers would wear a fringed decorative apron called a kesho-mawashi during the bout, whereas today these are worn only during pre-tournament rituals. Most of the rest of the current forms within the sport developed in the early Edo period.
Professional sumo (大相撲 ōzumō ) can trace its roots back to the Edo period in Japan as a form of sporting entertainment. The original wrestlers were probably samurai, often rōnin, who needed to find an alternative form of income. Current professional sumo tournaments began in the Tomioka Hachiman Shrine in 1684, and then were held in the Ekō-in in the Edo period. Western Japan also had its own sumo venues and tournaments in this period with by far the most prominent center being in Osaka. Osaka sumo continued to the end of the Taishō period in 1926, when it merged with Tokyo sumo to form one organization. For a short period after this four tournaments were held a year, two tournaments in locations in western Japan such as Nagoya, Osaka and Fukuoka, and two in the Ryōgoku Kokugikan in Tokyo. From 1933 onward tournaments were held almost exclusively in the Ryōgoku Kokugikan until the American occupation forces appropriated it and the tournaments were moved to Meiji Shrine until the 1950s. Then an alternate location, the Kuramae Kokugikan which was near Ryōgoku, was built for sumo. Also in this period, the Sumo Association began expanding to venues in western Japan again, reaching a total of six tournaments a year by 1958 with half of them in Kuramae. In 1984, the Ryōgoku Kokugikan was rebuilt and sumo tournaments in Tokyo have been held there ever since.
The winner of a sumo bout is either:
- The first wrestler to force his opponent to step out of the ring.
- The first wrestler to force his opponent to touch the ground with any part of his body other than the bottom of his feet.
There are also a number of other less common rules that can be used to determine the winner. For example a wrestler using an illegal technique (or kinjite) automatically loses, as does one whose mawashi (or belt) becomes completely undone. A wrestler failing to turn up for his bout (including through a prior injury) also automatically loses (fusenpai).
On rare occasions the referee or judges may award the win to the wrestler who touched the ground first; this happens if both wrestlers touch the ground at very nearly the same time and it is decided that the wrestler who touched the ground second had no chance of winning as, due to the superior sumo of his opponent, he was already in an irrecoverable position. The losing wrestler is referred to as being shini-tai (“dead body”) in this case.
Matches consist solely of a single round and often last only a few seconds, as usually one wrestler is quickly ousted from the circle or thrown to the ground. However, they can occasionally last for several minutes. Each match is preceded by an elaborate ceremonial ritual. Traditionally, sumo wrestlers are renowned for their great girth and body mass is often a winning factor in sumo. There are no weight divisions in professional sumo, and considering the range of body weights in sumo, an individual wrestler can sometimes face an opponent twice his own weight. However, with superior technique, smaller wrestlers can control and defeat much larger opponents.2
Sumo matches take place in a dohyō (土俵): a ring, 4.55 metres (14.9 ft) in diameter and 16.26 square metres (175.0 sq ft) in area, of rice-straw bales on top of a platform made of clay mixed with sand. A new dohyō is built for each tournament by the bout callers (or yobidashi). At the center are two white lines, the shikiri-sen, behind which the wrestlers position themselves at the start of the bout.3 A roof resembling that of a Shinto shrine may be suspended over the dohyō.
Professional sumo is organized by the Japan Sumo Association.4 The members of the association, called oyakata, are all former wrestlers, and are the only people entitled to train new wrestlers. All practicing wrestlers are members of a training stable (heya) run by one of the oyakata, who is the stablemaster for the wrestlers under him. Currently there are 47 training stables for about 660 wrestlers.5
All sumo wrestlers take wrestling names called shikona (四股名), which may or may not be related to their real names. Often wrestlers have little choice in their name, which is given to them by their trainer (or stablemaster), or by a supporter or family member who encouraged them into the sport. This is particularly true of foreign-born wrestlers. A wrestler may change his wrestling name several times during his sumo career.4 In rare instances, some sumo wrestlers have kept their real family names as their shikona, prominent examples being Wajima, Hasegawa and Shimotori.
Sumo wrestling is a strict hierarchy based on sporting merit. The wrestlers are ranked according to a system that dates back to the Edo period. Wrestlers are promoted or demoted according to their performance in six official tournaments held throughout the year. A carefully prepared banzuke listing the full hierarchy is published two weeks prior to each sumo tournament.6
In addition to the professional tournaments, exhibition competitions are held at regular intervals every year in Japan, and approximately once every two years the top ranked wrestlers visit a foreign country for such exhibitions. None of these displays is taken into account in determining a wrestler's future rank. Rank is determined only by performance in Grand Sumo Tournaments (or honbasho), which are described in more detail below.3
There are six divisions in sumo: makuuchi (maximum 42 wrestlers), jūryō (fixed at 28 wrestlers), makushita (fixed at 120 wrestlers), sandanme (fixed at 200 wrestlers), jonidan (approximately 185 wrestlers), and jonokuchi (approximately 40 wrestlers). Wrestlers enter sumo in the lowest jonokuchi division and, ability permitting, work their way up to the top division. A broad demarcation in the sumo world can be seen between the wrestlers in the top two divisions known as sekitori and those in the four lower divisions, known commonly by the more generic term rikishi. These differences in compensation, privileges and status are enumerated here.7
The topmost makuuchi division receives the most attention from fans and has the most complex hierarchy. The majority of wrestlers are maegashira and are numbered from one (at the top) down to about sixteen or seventeen. In each rank there are two wrestlers, the higher ranked is designated as "east" and the lower as "west", so the list goes #1 east, #1 west, #2 east, #2 west, etc.8 Above the maegashira are the three champion or titleholder ranks, called the san'yaku, which are not numbered. These are, in ascending order, komusubi, sekiwake, and ōzeki. At the pinnacle of the ranking system is the rank of yokozuna.7
Yokozuna, or grand champions, are generally expected to compete for and to win the top division tournament title on a regular basis. Hence the promotion criteria for yokozuna are very strict. In general, an ōzeki must win the championship for two consecutive tournaments or an "equivalent performance" to be considered for promotion to yokozuna.4 More than one wrestler can hold the rank of yokozuna at the same time.
In antiquity, sumo was solely a Japanese sport practiced by Japanese. Since the 1900s, however, the number of foreign-born sumo wrestlers has gradually increased. In the beginning of this period, these few foreign wrestlers were listed as Japanese, but particularly since the 1960s, a number of high profile foreign-born wrestlers became well-known and in more recent years have even come to dominate in the highest ranks. Half of the last six wrestlers promoted to ōzeki have been foreign born and there has not been a Japanese yokozuna since 2003. This and other issues eventually led the Sumo Association to limit the number of foreigners allowed in each stable to just one each. For more details on foreign participation in sumo see here.
As of 1958 there are six Grand Sumo tournaments (Japanese: honbasho) each year: three at The Sumo Hall (or Ryōgoku Kokugikan) in Ryōgoku, Tokyo (January, May, and September), and one each in Osaka (March), Nagoya (July) and Fukuoka (November). Each tournament begins on a Sunday and runs for 15 days, ending also on a Sunday.9 Each wrestler in the top two divisions (known as sekitori) has one match per day, while the lower ranked wrestlers compete in seven bouts, approximately one every two days.
Each day is structured so the highest-ranked contestants compete at the end of the day. Thus, wrestling will start in the morning with the jonokuchi wrestlers and end at around six o'clock in the evening with bouts involving the yokozuna. The wrestler who wins the most matches over the fifteen days wins the tournament championship (yūshō) for his division. If two wrestlers are tied for the top, they wrestle each other and the winner takes the title. Three-way ties for a championship are rare, at least in the top division. In these cases the three wrestle each other in pairs with the first to win two in a row taking the tournament. More complex systems for championship playoffs involving four or more wrestlers also exist, but these are usually only seen in determining the winner of one of the lower divisions.
The matchups for each day of the tournament are announced a day in advance. They are determined by the sumo elders who are members of the judging division of the Sumo Association. As there are many more wrestlers in each division than matchups during the tournament each wrestler will only compete against a selection of opponents from the same division, though there can be small overlap between two divisions. With the exception of the san'yaku ranked wrestlers the first bouts tend to be between wrestlers who are within a couple of ranks of each other. Afterwards the selection of opponents takes into account a wrestler's prior performance. For example in the lower divisions wrestlers with the same record in a tournament are generally matched up with each other, and the last matchups often involve undefeated wrestlers competing against each other, even if they are from opposite ends of the division. In the top division in the last few days wrestlers with exceptional records will often have matches against much more highly ranked opponents, including san'yaku wrestlers, especially if they are still in the running for the top division championship. Similarly more highly ranked wrestlers with very poor records may find themselves fighting wrestlers much further down the division. For the yokozuna and ōzeki the first week and a half of the tournament tends to be taken up with bouts against the top maegashira, the komusubi and sekiwake, with the bouts within these ranks being concentrated into the last five days or so of the tournament (depending on the number of top ranked wrestlers competing). It is traditional that on the final day the last three bouts of the tournament are between the top six ranked wrestlers, with the top two competing in the very final matchup, unless injuries during the tournament prevent this.
There are certain match-ups that are prohibited in regular tournament play. Wrestlers who are from the same training stable cannot compete against each other, nor can wrestlers who are brothers, even if they join different stables. The one exception to this rule is that training stable partners and brothers can face each other in a championship-deciding playoff match.
The last day of the tournament is called senshūraku, which literally means the pleasure of a thousand autumns. This colorful name for the culmination of the tournament echoes the words of the playwright Zeami to represent the excitement of the decisive bouts and the celebration of the victor. The Emperor's Cup is presented to the wrestler who wins the top division makuuchi championship. Numerous other (mostly sponsored) prizes are also awarded to him. These prizes are often rather elaborate, ornate gifts, such as giant cups, decorative plates, and statuettes. Others are quite commercial, such as one trophy shaped like a giant Coca-Cola bottle.
Promotion and relegation for the next tournament are determined by a wrestler's score over the 15 days. In the top division, the term kachikoshi means a score of 8–7 or better, as opposed to makekoshi which indicates a score of 7–8 or worse. A wrestler who achieves kachikoshi will almost always be promoted further up the ladder, the level of promotion being higher for better scores. See the makuuchi article for more details on promotion and relegation.
A top division wrestler who is not an ōzeki or yokozuna and who finishes the tournament with kachikoshi is also eligible to be considered for one of the three prizes awarded for "technique", "fighting spirit" and for defeating the most yokozuna and ōzeki the "outstanding performance" prize. For more information see sanshō
A top division wrestler will arrive at the stadium in the afternoon and enter the changing room. There are 'East' and 'West' rooms so competing wrestlers do not meet their opponents of the day before the match. The wrestler will change first into his keshō-mawashi, an ornate, embroidered silk 'apron', which he will wear during the ring entering ceremony, or dohyō-iri. There are four dohyō-iri on each day, two for jūryō and two for makuuchi division wrestlers. In each case there is a procession of those in the east changing room and one for those in the west. During the ceremony the wrestlers are introduced to the crowd one-by-one in ascending rank order and form a circle around the ring facing outwards. Once the highest ranked wrestler is introduced they turn inwards and perform a brief ritual before filing off and returning to their changing rooms. Yokozuna have a separate, more elaborate dohyō-iri; see yokozuna.
Once in the changing room the wrestlers change into their fighting mawashi and await their bouts. The wrestlers reenter the arena two bouts before their own and sit down at the side of the ring. When it is their turn they will be called into the ring by a yobidashi (announcer) and they will mount the dohyō.10
On mounting the dohyō the wrestler performs a number of rituals derived from Shinto practice. Facing the audience, he claps his hands and then performs the leg-stomping shiko exercise to drive evil spirits from the dohyō as the gyōji, or referee, who will coordinate the bout announces the wrestlers' names once more.
In addition, the top two divisions add even more rituals. Stepping out of the ring into their corners, each wrestler is given a ladleful of water, the chikara-mizu ("power water"), with which he rinses out his mouth; and a paper tissue, the chikara-gami ("power paper"), to dry his lips. Each wrestler receives these from a wrestler from his side of the ring (east or west). He cannot receive them from a wrestler who has lost his bout lest he be contaminated by the other's defeat. Accordingly, he will receive these from wrestler who competed in the bout preceding his, or if that wrestler lost his bout, from the wrestler who will compete in the following bout. Both wrestlers then step back into the ring, squat facing each other, clap their hands, then spread them wide (traditionally to show they have no weapons). Returning to their corners they each pick up a handful of salt which they toss onto the ring to purify it.
Finally the wrestlers crouch down at the shikiri-sen, or starting lines, each trying to stare the other down. When both wrestlers place both fists on the ground on or behind the shikiri-sen, they spring from their crouch for the tachi-ai (the initial charge). In the lower divisions they are expected to start more or less immediately. However, in the upper divisions they almost never charge on the first occasion. Instead, after staring at one another, they return to their corners for more mental preparation. More salt is thrown whenever they step back into the ring where they will again crouch and glare at one another in a build up to the actual bout. This can happen a number of times (about three, or even more in the case of the highest ranks) until on the last occasion the referee informs them they must start the bout. The total length of time for this preparation is around four minutes for the top division wrestlers.
At the initial charge both wrestlers must jump up from the crouch simultaneously after touching the surface of the ring with two fists at the start of the bout, and the referee can restart the bout if this simultaneous touch does not occur. Upon completion of the bout, the referee must immediately designate his decision by pointing his gunbai or war-fan towards the winning side. The referee's decision is not final and may be disputed by the five shimpan (judges) seated around the ring. If this happens they will meet in the center of the ring to hold a mono-ii (lit: a talk about things). After reaching a consensus they can uphold or reverse the referee's decision or order a rematch, known as a torinaoshi. The wrestlers will then return to their starting positions and bow to each other before retiring. A winning wrestler in the top division may receive additional prize money in envelopes from the referee if the matchup has been sponsored. If a yokozuna is defeated by a lower ranked wrestler, it is common and expected for audience members to throw their seat cushions into the ring (and onto the wrestlers), though this practice is technically prohibited.
In contrast to the time in bout preparation, bouts are typically very short, usually less than a minute, and often only a few seconds. Extremely rarely a bout can go on for many minutes (up to four minutes), in which case the referee or one of the judges sitting around the ring may call a mizu-iri or "water break". The wrestlers are carefully separated, have a brief break and then return to the exact position they left off in. It is the referee's responsibility to reposition the wrestlers. If after four more minutes they are still deadlocked they may have a second break, after which they start from the very beginning. Further deadlock with no end of the bout in sight can lead to a draw (hikiwake), an extremely rare result in modern sumo. The last draw in the top division was in September 1974.4
A sumo wrestler leads a highly regimented way of life. The Sumo Association prescribes the behavior of its wrestlers in some detail. For example, in the wake of a serious car accidentcitation needed involving a wrestler the Association banned wrestlers from driving their own carscitation needed. Breaking the rules can result in fines and/or suspension, not only for the offending wrestler, but also for his stablemaster.
On entering sumo, they are expected to grow their hair long to form a topknot, or chonmage, similar to the samurai hairstyles of the Edo Period. Furthermore they are expected to wear the chonmage and traditional Japanese dress when in public. Consequently, sumo wrestlers can be identified immediately when in public.
The type and quality of the dress depends on the wrestler's rank. Rikishi in jonidan and below are allowed to wear only a thin cotton robe called a yukata, even in winter. Furthermore, when outside they must wear a form of wooden sandals called geta that make a distinctive clip-clop sound as one walks in them. Wrestlers in the makushita and sandanme divisions can wear a form of traditional short overcoat over their yukata and are allowed to wear straw sandals, called zōri. The higher ranked sekitori can wear silk robes of their own choice and the quality of the garb is significantly improved. They also are expected to wear a more elaborate form of topknot called an ōichō (lit. big ginkgo leaf) on formal occasions.
Similar distinctions are made in stable life. The junior wrestlers must get up earliest, around 5 am, for training whereas the sekitori may start around 7 am. When the sekitori are training the junior wrestlers may have chores to do, such as assisting in cooking the lunch, cleaning and preparing the bath, or holding a sekitori's towel. The ranking hierarchy is preserved for the order of precedence in bathing after training, and in eating lunch.
Wrestlers are not normally allowed to eat breakfast and are expected to have a form of siesta after a large lunch. The most common type of lunch served is the traditional sumo meal of chankonabe which consists of a simmering stew cooked at table which contains various fish, meat, and vegetables. It is usually eaten with rice and washed down with beer. This regimen of no breakfast and a large lunch followed by a sleep is intended to help wrestlers put on weight so as to compete more effectively.
In the afternoon the junior wrestlers will again usually have cleaning or other chores to do, while their sekitori counterparts may relax, or deal with work issues related to their fan clubs. Younger wrestlers will also attend classes, although their education differs from the typical curriculum of their non-sumo peers. In the evening sekitori may go out with their sponsors while the junior wrestlers generally stay at home in the stable, unless they are to accompany the stablemaster or a sekitori as his tsukebito (manservant) when he is out. Becoming a tsukebito for a senior member of the stable is a typical duty. A sekitori will have a number of tsukebito, depending on the size of the stable. The most junior are given the most mundane tasks and only the senior tsukebito will accompany the sekitori when he goes out.
The sekitori also are given their own room in the stable or, may live in their own apartments, as do married wrestlers. In contrast, the junior wrestlers sleep in communal dormitories. Thus the world of the sumo wrestler is split broadly between the junior wrestlers, who serve, and the sekitori, who are served. Life is especially harsh for new recruits, to whom the worst jobs tend to be allocated, and there is a high dropout rate at this stage.
The negative health effects of the sumo lifestyle can become apparent later in life. Sumo wrestlers have a life expectancy of between 60 and 65, more than 10 years shorter than the average Japanese male. Many develop diabetes, high blood pressure, and are prone to heart attacks. The excessive intake of alcohol can lead to liver problems and the stress on their joints can cause arthritis. Recently, the standards of weight gain are becoming less strict, in an effort to improve the overall health of the wrestlers.1112
- yokozuna: 2,820,000, about US$30,500
- ōzeki: 2,347,000, about US$25,000
- san'yaku: 1,693,000, about US$18,000
- maegashira: 1,309,000 or about US$14,000
- jūryō: 1,036,000, about US$11,000
Wrestlers lower than the second division, who are considered to be trainees, receive only a fairly small allowance instead of a salary.
In addition to the basic salary, sekitori wrestlers also receive additional bonus income, called mochikyukin, six times a year (once every tournament, or basho) based on the cumulative performance in their career to date. This bonus increases every time that the wrestler scores a kachikoshi (with larger kachikoshi giving larger raises). Special increases in this bonus are also awarded for winning the top division championship (with an extra large increase for a "perfect" championship victory with no losses), and also for scoring a gold star or kinboshi (an upset of a yokozuna by a maegashira).
san'yaku wrestlers also receive a relatively small additional tournament allowance, depending on their rank, and yokozuna receive an additional allowance every second tournament, associated with the making of a new tsuna belt worn in their ring entering ceremony.
There is also prize money for the winner of each divisional championship, which increases from 100,000 yen for a jonokuchi victory up to 10,000,000 yen for winning the top division. In addition to prizes for a championship, wrestlers in the top division giving an exceptional performance in the eyes of a judging panel can also receive one or more of three special prizes (the sansho) which are worth 2,000,000 yen each.14
Individual top division matches can also be sponsored by companies. In such cases the winner of the bout typically receives around 30,000 yen net per sponsor (out of the sponsors contribution of 60,000 yen—much of the remainder goes in paying the wrestler's tax on the prize). These bout prizes are called kenshōkin. For bouts involving yokozuna and ōzeki the number of sponsors of the matchup can be quite large, whereas for lower ranked matchups there may be no bout sponsors at all unless one of the wrestlers is particularly popular, or unless a company has a policy of sponsoring all his matchups. No bout prize money is awarded for a bout decided by a fusenshō or forfeit victory.
Sumo is also an amateur sport, with participants in college, high school and grade school in Japan. In addition to college and school tournaments, there are also open amateur tournaments. The sport at this level is stripped of most of the ceremony. The most successful amateur wrestlers in Japan (usually college champions) can be allowed to enter professional sumo at makushita (third division) rather than from the very bottom of the ladder. This rank is called makushita tsukedashi, and is currently makushita 10 or 15 depending on the level of amateur success achieved. Many of the current top division wrestlers entered professional sumo by this route. All entry by amateur athletes into the professional ranks is subject to them being young enough (under 23) to satisfy the entry requirements, barring qualification as a makushita tsukedashi (under 25).
There is also an International Sumo Federation, which encourages the sport's development worldwide, including holding international championships. A key aim of the federation is to have Sumo recognized as an Olympic sport. Accordingly, amateur tournaments are divided into weight classes (men: Lightweight up to 85 kg (187 lb), Middleweight up to 115 kg (254 lb), Heavyweight over 115 kg (254 lb), and Open Weight [unrestricted entry]), and include competitions for female wrestlers (Lightweight up to 65 kg (143 lb), Middleweight up to 80 kg (180 lb), Heavyweight over 80 kg (180 lb), and Open Weight).
Amateur sumo clubs are gaining in popularity in the United States, with competitions regularly being held in major cities across the country. The US Sumo Open, for example, was held in the Los Angeles Convention Centre in front of 3000.15 The sport has long been popular on the West Coast and in Hawai'i, where it has played a part in the festivals of the Japanese ethnic communities. Now, however, the sport has grown beyond the sphere of Japanese diaspora and athletes come from a variety of ethnic, cultural and sporting backgrounds.
Amateur sumo is particularly strong in Europe. Many athletes come to the sport from a background in judo, freestyle wrestling, or other grappling sports such as Sambo. Some Eastern European athletes have been successful enough to be scouted into professional sumo in Japan, much like their Japanese amateur counterparts. The most notable of these to date is the Bulgarian Kotoōshū, who is the highest ranking foreign wrestler who was formerly an amateur sumo athlete.
- Controversies in professional sumo
- Glossary of sumo terms
- List of active sumo wrestlers
- List of past sumo wrestlers
- List of sumo stables
- List of sumo record holders
- List of sumo tournament top division champions
- List of sumo tournament second division champions
- List of years in sumo
- List of yokozuna
- "Sumo East and West", documentary on Sumo
- "Decline in apprentices threatens future of national sport". Asahi Shimbun. Retrieved June 23, 2013.
- "Rules of Sumo". Beginner's Guide of Sumo. Japan Sumo Association. Retrieved June 26, 2007.
- Hall, Mina (1997). The Big Book of Sumo: History, Practice, Ritual, Fight. Stone Bridge Press. ISBN 1-880656-28-0.
- Sharnoff, Lora (1993). Grand Sumo. Weatherhill. ISBN 0-8348-0283-X.
- "Sumo Beya Guide". Japan Sumo Association. Retrieved July 8, 2007.
- Kamiya, Setsuko, "Steeped in tradition, Shinto, sumo is also scandal-stained", Japan Times, February 19, 2010, p. 3.
- "Banzuke". Beginner's Guide of Sumo. Japan Sumo Association. Retrieved June 27, 2007.
- Professional rankings: The Banzuke
- An exception to this rule occurred when Hirohito, the former Emperor of Japan, died on Saturday, January 7, 1989. The tournament which was to start on the following day was postponed; starting on Monday, January 9 and finishing on Monday, January 24.
- Schuler, Nicolas; Macan, Jelena (trans.) (April 2004). "Detailed description of a sumo bout". Le Monde de Sumo N°3. Retrieved August 3, 2007.
- "Becoming a Sumo Wrestler". Sumo East and West. Discovery Channel. Retrieved November 18, 2005.
- "United Nations Statistics Division – Demographic and Social Statistics". Retrieved November 18, 2005.
- "Rikishi Salaries" (in Japanese). Retrieved October 29, 2007.
- "Sumo Questions". Retrieved November 18, 2005.
- My First Date With Sumo (2007) Gould, Chris http://www.amazon.com/My-First-Date-Sumo-ebook/dp/B0061BMG0O
- Benjamin, David (1991). The Joy of Sumo: A Fan's Notes. Rutland, Vermont, U.S.A. & Tokyo, Japan: Charles E. Tuttle Company. ISBN 0-8048-1679-4.
- Gould, Chris (2011). Sumo Through the Wrestlers' Eyes. Amazon. ASIN B006C1I5K8.
- Gould, Chris (2007, revised: 2011). My First Date With Sumo. Amazon. ASIN B0061BMG0O.
- Schilling, Mark (1994). Sumo: A Fan's Guide. Tokyo, Japan: The Japan Times, Ltd. ISBN 4-7890-0725-1.
- Shapiro, David (1995). Sumo: A Pocket Guide. Rutland, Vermont, U.S.A. & Tokyo, Japan: Charles E. Tuttle Company. ISBN 0-8048-2014-7.
- Sharnoff, Lora (1993). Grand Sumo. Weatherhill. ISBN 0-8348-0283-X.
- Tablero, Fco. Javier (2002). Parentesco y organización del sumo en Japón. Madrid: Universidad Complutense de Madrid. ISBN 84-8466-257-8.
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- Nihon Sumo Kyokai Official Grand Sumo Home Page
- The Sumo Forum
- Sumo FAQ
- Searchable Sumo Database
- Sumo News and Analysis
- A Matter of Size, an Israeli fictional film on Amateur Sumo (2009)