"Developing inner strengths by
following the path of harmony."

February 8, 1995

i. Introduction[toc]

This document is copyright 1995 by Neil Gendzwill, all rights reserved. Permission is granted for free distribution in electronic or hard copy, provided that the document is maintained as a complete work. Copying or distribution for profit is expressly denied.

This FAQ is intended to cover all aspects of Japanese swordsmanship. However, my particular bent is towards kendo, so any flames about other arts are probably deserved. Heck, corrections or additions on anything in this document are welcome. Please *mail* comments to gendzwill@SEDSystems.ca. Please do *not* reply to the account which posted the FAQ. If you have comments, I'll either incorporate your changes or explain to you why I didn't.

This FAQ has been cross-posted to rec.martial-arts, rec.sport.fencing and the iaido-l mailing list. It is also available by anonymous FTP from two sites: see section 5 for details.

ii. Acknowledgements[toc]

Thanks to Jens Nilsson for the WKC results and European federation addresses and Don Seto for most of the rest of the organization addresses. If your organization has been overlooked or has inaccuracies in its entry, let me know.

Thanks to Frank Lindquist and Richard Stein for Section 15 (on purchasing nihon-to).

Thanks to all the members of iaido-l who have helped expand my knowledge, especially the owners, Kim Taylor and Johanna Botari, and the owner-operator of the FTP site, Ron Fox. Thanks to Kim for the information on the ko-ryu. Thanks to all who have written, your comments have been incorporated where possible.

iii. Table o' Contents

i. Introduction

ii. Acknowledgements

iii. Table o' Contents

1. What is kendo?

1a. OK, then what is kenjutsu?

1b. Isn't bokken technique taught in aikido?

1c. What is kumdo?

1d. Are there different styles of kendo/kenjutsu?

2. What is iaido?

2a. OK, then what is iaijutsu?

2b. Are there different styles of iaido/iaijutsu?

3. What about batto-jutsu, tameshi-giri, shinkendo and others?

3a. OK, so if they're watered down, why study kendo or iaido?

4. How do I find a school?

4a. How do I evaluate a school?

5. Are there any other net.resources?

6. How did kendo originate?

7. How did iaido originate?

8. What are those funny clothes kendo and iaido players wear?

8a. Why do they wear hakama?

8b. What virtues do the hakama pleats represent?

9. How is a Japanese sword constructed?

9a. How many layers in a Japanese sword?

9b. What are the different types of Japanese swords?

10. What sort of weapons are used for practice?

1. What is kendo?[toc]

Kendo is the way of the sword, Japanese fencing. About 8 million people worldwide participate, 7 million of them in Japan. It is taught as part of the school physical education curriculum. College kendo teams in Japan are high-profile; major competitions are televised complete with colour commentary.

Kendoka wear armour protecting the head, throat, wrists and abdomen; these are the only legal targets. The split-bamboo practice sword, called a shinai, is wielded two-handed; the kendoka faces his opponent squarely. A small number of high-level practitioners utilize a shinai in each hand. Kendoka move using a peculiar gliding step refined for use on the smooth floors of the dojo.

1a. OK, then what is kenjutsu?[toc]

*Generally* (but not always) in Japanese martial arts, the "do" forms are those used to improve the self, while the "jutsu" forms concentrate on teaching the techniques of war.

The art of winning real fights with real swords is kenjutsu. The goal of kenjutsu is victory over opponents; the goal of kendo is to improve oneself through the study of the sword. Kendo also has a strong sporting aspect with big tournaments avidly followed by the Japanese public. Thus kendo could be considered the philosophical/sporting aspect of Japanese swordsmanship.

In terms of learning to fight with a sword, kenjutsu has a more complete curriculum. Kendo of necessity limits the range of techniques and targets. Kendoka generally use shinai, which allow techniques which do not work with real swords. Kenjutsu practitioners do not usually use shinai in training, preferring to use bokken (wooden swords) or katana (steel swords) in order to preserve the cutting techniques of real sword fighting. Kenjutsu training largely consists of practicing cutting technique and performing partner kata.

In some ryu, there is contact, which usually happens in a controlled manner within a partner kata. Some of the ryu use protective equipment, such as the gloves and head padding of the Maniwa Nen Ryu. Others, Shinkage Ryu in particular, use a fukuro shinai which is made of bamboo split into many pieces at the end and completely covered with leather.

1b. Isn't bokken technique taught in aikido?[toc]

Yes, with qualifications. Not every aikido dojo offers qualified instruction in actual sword techniques. Many of them use bokken practice only as a way of better understanding the empty-handed techniques, as these techniques are grounded in kenjutsu.

Ueshiba-sensei was trained in many styles of bujutsu, including kenjutsu, jojutsu and aikijutsu. He distilled and modified the myriad of techniques he knew into modern aikido. Most modern students do not have the time or inclination to learn the empty handed curriculum as well as bokken and jo, so the concentration tends to be on the aiki techniques. Even among those dojos which emphasize bokken, the techniques are somewhat different from kenjutsu. Ueshiba-sensei's swordsmanship was excellent, incidentally. Should you ever get an opportunity to watch film of him with a bokken, take it.

1c. What is kumdo?[toc]

Kumdo is the korean word for kendo. They wear different clothing and dispense with the Japanese terminology for reasons based on racial enmity, but the techniques are sufficiently similar for Korea to compete successfully in international tournaments.

1d. Are there different styles of kendo/kenjutsu? [toc]

Kendo is pretty much the same world-wide. Most dojos are governed by the International Kendo Federation (IKF), which grew from the Zen-Nippon Kendo Renmei (ZNKR, the All-Japan Kendo Federation). There is a second federation in Japan, not as popular, but the differences are more political than technical.

There used to be many kenjutsu ryu; only a handful have survived. One of the oldest is Tenshin Shoden Katori Shinto Ryu. There is also Itto Ryu, from which much of modern kendo is derived. Bokuden Ryu, Kashima Ryu and Maniwa Nen Ryu still survive. Two branches of Musashi's Niten Ichi Ryu are still going: Hyo Ho Niten Ichi (also called Noda Ha) and Santo Ha. Yagyu family kenjutsu survives as Shinkage Ryu, probably the most popular of the modern kenjutsu traditions.

2. What is iaido? [toc]

Iaido is the art of drawing and attacking with a sword, although a more indepth reading of the Japanese characters for iaido results in (very roughly) "the way of harmonizing oneself in action". Iaidoka (and kendoka) wield a sword not to control their opponent, but to control themselves.

Iaido is performed solo as a series of kata, executing varied techniques against single or multiple imaginary opponents. In addition to sword technique, it requires imagination and concentration in order to maintain the feeling of a real fight and to keep the kata fresh. Iaidoka are often recommended to practice kendo to preserve that fighting feel; it is common for high ranking kendoka to hold high rank in iaido and vice versa.

2a. OK, then what is iaijutsu? [toc]

Iaijutsu is the art of killing on the draw. Iaijutsu teaches how to draw quickly and in such a fashion as to negate an opponents attack with finality.

Seitei-gata iaido (that set of techniques recommended by the ZNKR) is like a moving meditation - the draw and cut are very deliberate, formalized and beautiful. It is as far removed from iai-jutsu as kendo is from kenjutsu. Iaijutsu is more direct and forceful, less concerned with the state of the practitioner's mind and more with dispatching the opponent.

Having said that, iaido schools are generally affiliated with a particular ryu of iaido. In addition to the seitei-gata, students also learn their own ryu's techniques, which may be close to the seitei-gata in feeling or close to what is described here as iaijutsu. It's not completely black and white.

2b. Are there different styles of iaido/iaijutsu? [toc]

Iai is like karate, it is a broad "method of combat" which involves drawing and cutting like karate involves kicking and punching. The various styles are just that, styles. The main thrust stays constant.

The only (legitimate) ryu that usually calls itself iaijutsu that the author knows of is the Tenshin Shoden Katori Shinto Ryu. Katori Shinto Ryu is a bujutsu ryu, meaning many types of armed and unarmed combat are taught. Most other so-called iaijutsu schools are run by charlatans.

Two of the oldest iaido ryu extant today are Tatsumi Ryu and Shindo Munen Ryu. The other ryu listed here, and most of the ryu practiced today come from a common root, the Muso Ryu of Hayashizaki Jinsuke Shigenobu. These include Sekiguchi Ryu, Hoki Ryu, Tamiya Ryu, Jushin Ryu, Suio Ryu and Ichinomiya Ryu.

The most popular (in terms of numbers of students) forms of iaido are represented by the Muso Jikiden Eishin Ryu and the Muso Shinden Ryu. The iaido of the ZNKR is heavily based on these two schools, that of the ZNIR (Zen-Nippon Iaido Renmei, the All-Japan Iaido Federation) mostly based on the former. Most modern students belong to one of the two ryu, plus the ZNKR or ZNIR.

Toyama Ryu and Dai Nihon Batto Ho are offshoots of Muso Jikiden Eishin Ryu, although Toyama Ryu is actually just a subset.

There are many other ryu, especially in Japan. This has been a partial listing of the most popular.

3. What about batto-jutsu, tameshi-giri, shinkendo and others? [toc]

Again, *generally*, batto-jutsu is another word for iaijutsu, tameshi-giri is the art of physically cutting with the sword and shinkendo is fencing from a real sword perspective.

However, hundreds of years ago, the various sword teachers called their arts by various names which all designated more or less complete curricula of sword technique. In other words, what one ryu called kendo (or iaijutsu, or kenjutsu, or batto-jutsu) in the 15th century is not the same as what we call kendo today - it would have incorporated techniques of fencing, drawing and cutting, as no swordsman would be sufficiently trained without all three skills.

3a. OK, so if they're watered down, why study kendo or iaido? [toc]

Studying swordsmanship in the late 20th century is not a practical matter. Unlike the various empty-handed arts, there is no direct application for self-defence. You are unlikely to whip out a katana or bokken when accosted in a dark alley.

People start the study of swordsmanship for a variety of reasons. Those who study for a long time end up staying for two reasons: they enjoy the practice, and they feel they improve themselves through their practice. These things can be accomplished through kendo and iaido, in fact some might say they are more readily accomplished through the do forms, as that is their intent. Note that just because an art is labelled jutsu does not mean that there is no spiritual side to the training; that is a distinction that separates the most extreme sides to each style.

If your interest is in accurate and realistic sword technique applications, then you may not be satisfied with kendo or iaido. Be aware that *qualified* instructors of kenjutsu or iaijutsu are extremely difficult to find. There are only a handful in the US, none that I know of in Canada, and a whole passle of charlatans. Even the handful that are generally considered legitimate, including Lovret and Obata, have their detractors.

4. How do I find a school? [toc]

The operative word here is "a". Unless you're lucky enough to be living in Japan or an area with a large Japanese community, there may only be one choice in your area, and it may be iaido rather than kendo, kendo rather than kenjutsu, and so forth. In North America, prime areas include: San Francisco, southern California, Seattle, New York City, Vancouver and Toronto.

Lists of dojos for North America and Europe can be found on the iaido-l FTP site - check section 5 for details. If you don't have FTP access, send mail to gendzwill@sedsystems.ca and I'll rummage the lists for you.

Bear in mind that the lists may not be complete or may be out of date. If there is nothing in your area or if the contact for your area is a dead end, contact the next closest dojo and ask for help.

4a. How do I evaluate a school? [toc]

If you are looking at a kendo dojo, they should be affiliated with the International Kendo Federation through the local federation. For example, dojos in Canada belong to a local federation such as the Ontario Kendo Federation, which is in turn a member of the Canadian Kendo Federation, which is a member organization of the I.K.F. Dojos in the U.S. are likewise linked through a regional federation such as the Pacific Northwest Kendo Federation to the All U.S. Kendo Federation and then to the I.K.F.

If you are looking at a iaido dojo, then a similar association through the I.K.F. would be one sign of legitimacy, or else a link to the Zen Nippon Iaido Renmei. Not all iaido dojos belong to one of the two federations, though. In that case, you should ask what ryu (tradition or school) the dojo belongs to and what the instructor's qualifications are.

For federation-affiliated kendo and iaido, ideally the instructor should be at least yondan (4th degree). But in some isolated areas that is not possible and you may find a junior person doing the best they can.

If you have your heart set on kenjutsu or iaijutsu you are probably out of luck. Instructors are few and far between. If you find a school, be cautious - there are frauds about. Be especially wary if a lot of money is being charged. Kendo and iaido instructors are always volunteer and most legitimate kenjutsu instructors work the same way. Another warning sign is if the kenjutsu classes are offered as one of many styles taught by the same school - "we teach karate, jujutsu, tai chi and kenjutsu at Bubba's Black Belts". Similar to unaffiliated iaido dojos, find out what the ryu is, what the instructor's qualifications are and who his teacher is. If you get unsatisfactory answers or the questions are being dodged, don't join.

Ask if you can observe a class - there should be no problem. When visiting a class, arrive early and stay for the entire class. If you have questions, ask them before class or save them for after class. Be polite.

At the rec.martial-arts FTP site, you can locate the Newbie Guide to the martial arts, which has some good generic advice on locating a dojo.

5. Are there any other net.resources? [toc]

Why, yes there are.

The rec.martial-arts FTP site is cs.huji.ac.il ( This FAQ may be found in the directory /pub/doc/faq/rec/martial.arts, file name sword-art-faq.txt.gz. The file is g-zipped ASCII text.

The iaido-l FTP site is rudolf.nscl.msu.edu. Login with the username anonymous and any password you feel like using. The directory is /pub/iaido. Currently the site contains a number of good things. 00files.txt has the complete list and instructions for use, but in brief you can find dojo lists for kendo and iaido for North America and Europe, several glossaries, a set of True Type kanji fonts, some GIFs, a number of Quicktime clips and lists of literature, as well as this FAQ.

The FTP availability of this FAQ usually lags the posting date by a few days for new versions, so if you find an older version at either site, wait a while.

If you are interested in more information on sword arts, subscribe to the iaido-l mailing list. Covering mostly iaido, kendo and sword collection, but also kenjutsu and iaijutsu, this excellent service comes to us courtesy of Kim Taylor and Johanna Botari. Send e-mail to:


with the only contents being:

SUBSCRIBE iaido-l Your Real Name

Wouldn't hurt to have it in the subject either. Once you're on, send mail to iaido-l@uoguelph.ca to contribute.

There arent too many web sites about, here is the only one I know of:


6. How did kendo originate? [toc]

The earliest swords known to exist in Japan were of Chinese style and origin and date to the 2nd century BC. These ancient swords are referred to as ken, the Japanese pronunciation of the Chinese ideogram for sword or knife. From this term comes kendo, way of the sword, and kenjutsu, art of the sword.

Japanese sword technology began to outstrip the continental blades around 700 AD, with the advent of the first curved swords. Japanese historians refer to three stages of swordsmanship in ancient times - joko- ryu, chuko-ryu and shinto-ryu (ancient, middle and new styles).

One of two people are credited with the founding of kenjutsu, the synthesis of the ancient styles. The Kojiki and the Nihon-shoki (the 2 main references for ancient Japanese history) refer to Choisai Iizasa. Other historians refer to Kumimatsu no Mahito, a famous swordsman whose style is fabled to be the Kashima no tachi or Kashima Shrine style, which continues to this day.

Reference to the use of bokken (wooden sword) for fighting and training date back to 400 AD. This was followed by tachikaki, the art of drawing the sword. From this various ryus, or styles, developed. Once a fencing master became famous, he would form a ryu to give his name to the particular technique he had developed. Tachikaki developed into tachiuchi (match with swords) by the 8th century, after which there was slow development in kenjutsu.

In the 14th century, kenjutsu became popular once more. Dojos began to be established to teach kenjutsu and perpetuate ryu. Around that time, Kagehisa Ittosai Ito achieved a reputation for peerless swordsmanship and deep-thinking philosophy. He named himself Ittosai (one sword man) and founded Itto-ryu, the one sword school. It still exists today and strongly influences modern kendo.

In the 16th century, the Shinkage ryu was founded and remains one of the more popular kenjutsu ryu. Kami-izumi-ise-no-kami, the founder is credited with the invention of the fukuro shinai, a bamboo sword split 16 or 32 ways and completely covered in leather.

In the mid-18th century, Chuto Nakanishi developed the modern four- piece shinai and the kote (gloves). The do (chestplate) and men (helmet) followed, and by the end of the century, the practice armour and weapons had been refined into more or less the form they are used today. The new equipment required a new set of rules for the dojo, and the new style of fencing became known as kendo.

In 1871 the Japanese government made kendo compulsory training in schools and emphasis was placed on the mental, moral and physical value of training in an ancient martial art. Kendo was slowly becoming a sport. When the government banned the public wearing of swords in 1878, kenjutsu was barely able to survive. The Japanese police are credited with much of the effort in keeping swordsmanship alive during this period.

In 1909, the first college kendo federation was formed, followed by the Zen-Nippon Kendo Renmei (ZNKR, All-Japan Kendo Federation) in 1928. This federation, along with the Zen-Nippon Iaido Renmei (ZNIR, All-Japan Iaido Federation), govern kendo and iaido today.

7. How did iaido originate? [toc]

The above history of kendo/jutsu applies also to iaido/jutsu. In the latter half of the 15th century, Ienao Izasa (also known as Choisai Izasa) founded the Tenshin Shoden Katori Shinto Ryu. Together with his leading swordsman, he devised the art of attacking with the draw called iai-jutsu. In the early part of the 16th century, the Tatsumi Ryu and Takenouchi Ryu also practiced iai-jutsu.

In the late 16th century, Shigenobu Jinsuke allegedly was divinely inspired to develop a new sword-drawing art. He renamed himself Hayashizaki after the inspirational place and founded the Shimmei Muso Ryu to teach his art, called batto-jutsu. He was one of the first to teach swordsmanship as a way for spiritual development. Popularly misidentified as the originator of iai-jutsu, his influence has been great. More than 200 ryu have been founded in the wake of Jinsuke's inspiration and image, many of them named after him.

Various headmasters in the line of Jinsuke's teachings formed their own ryu. Among them were Shigemasa Tamiya (Tamiya Ryu), Kinrose Nagano (Muraku Ryu) and Eishin Hasegawa (Muso Jikiden Eishin Ryu), who were the 1st, 3rd and 7th headmasters descending from Jinsuke. The ryu which branched out from the teachings of these and others are too numerous to mention here.

Hakudo Nakayama, who lived at the beginning of the 20th century, studied Omori Ryu, Muraku Ryu and Muso Jikiden Eishin Ryu and was experienced in all aspects of swordsmanship. He became the 16th and last undisputed successor to the Jinsuke/Eishin line. He also studied Shindo Munen Ryu and Yamaguchi Itto Ryu. He went on to develop his own style, Muso Shinden Ryu batto-jutsu. Due to his diverse experience, the ryu boasted a bewildering array of techniques. He was asked to develop a simplified curriculum. He did so, and made the techniques available to all interested persons, largely kendoka. These forms of iai-jutsu, along with others, were gradually restyled as iaido in the late 40s.

In 1967, the Zen-Nippon Kendo Renmei formed a committee to develop a standardized curriculum of study for iaido. This curriculum was to be recommended as study to students of kendo, who were losing touch with the dynamics of combat with real swords. Members of Muso Jikiden Eishin Ryu, Muso Shinden Ryu and Hoki Ryu recommended a curriculum of seven kata that became known as the seitei gata. In 1977, another committee from the same ryu plus Tamiya Ryu added three more kata to the seitei gata.

The seitei-gata iaido has the largest popular following in Japan and abroad. The Zen-Nippon Iaido Renmei was formed in 1948, and has done a great deal of work to promote iai-jutsu and iaido. It has its own autonomy and standards.

Only a handful of ryu are represented by the major organizations; thus the hundreds of traditional iai-jutsu ryu did not contribute to the foundation of iaido. Classical iai-jutsu exists today but largely goes its separate way from iaido.

8. What are those funny clothes kendo and iaido players wear? [toc]

The top is called a keiko-gi (also kendo-gi or just gi). It is a heavy, quilted cotton shirt with three-quarter length sleeves. The kendo-gi is very similar to the top of the judo uniform, but longer. Iaidoka usually wear a gi about the same weight as a karate uniform. Kenjutsuka and iaijutsuka wear what kendoka and iaidoka wear, respectively.

The bottom is called a hakama. It is a pleated, divided skirt (the modern term might be a culotte, but that's not strictly accurate) generally made of cotton or cotton-poly blend. The hakama are the same as aikidoka wear, except that kendo/iaido attaches no particular grade to the hakama. In my club, we let beginners wear them as soon as the footwork is solid enough that we don't have to correct it constantly (the hakama hides the feet).

Traditionally, the hakama is black or indigo blue for men and white for women. The gi is blue or white. Iaidoka sometimes wear all black or all white regardless of sex. Children's gi have a diamond-shaped line pattern on them. Most people wear all blue. A good quality Japanese gi is died with natural indigo, and so is the kendoka wearing it until the salt from sweat sets the dye. You can also cheat and wash a new gi in cold water and salt before wearing.

8a. Why do they wear hakama? [toc]

Hakama and keiko-gi are robust versions of the formal samurai clothing of the 18th and 19th centuries. They are worn during sword practice, in preference to something like the clothes worn in karate, to emphasize the formality of occasion. Kendo or iaido training is meant to be more than just physical training, and the choice of clothes emphasizes this. Additionally, the clothes add grace and dignity to an already graceful and dignified art.

From a practical standpoint, the hakama is cool and comfortable, allows easy movement and disguises the feet from the opponent.

8b. What virtues do the hakama pleats represent? [toc]

1: Jin (benevolence)

2: Gi (justice)

3: Rei (manners)

4: Chi (wisdom)

5: Shin(faithfulness, trustfulness)

9. How is a Japanese sword constructed? [toc]

Very carefully.

Seriously, there are as many as a half-dozen people involved in the construction of a sword.

The swordsmith forges the actual blade. He starts usually with a special kind of traditional Japanese steel called tamahagane, and works with hammer and forge to fold it a number of times. There are two processes in general, one to make core steel (shinganae) and the other to make jacket steel (kawagane). Kawagane is folded more times and ends up being harder and less ductile than shinganae. In the most simple construction, a piece of kawagane is folded around a piece of shinganae to form a jacketed core. Thus the shinganae allows the sword to flex instead of breaking on impact, and the kawagane allows it to take the famous razor edge. More complicated construction methods can produce swords made of as many of 5 pieces of steel, all forged differently.

The folding process is used to closely control the uniformity and carbon content of the steel. An accomplished smith can tell by eye to within a tenth of a percent the carbon content of a piece of steel.

When the basic blank has been constructed, the smith will continue to work what is essentially a metal bar into the shape of the sword. When the forging is done, the blade is the correct length, curvature and general shape, but lacks a finish and certain of the various edges and features. The smith will then use coarse polishing stones to further define the blade before passing it onto the polisher.

The polisher uses successive grades of stone to finish the blade. The polisher is responsible for the famous edge, but that is only one part of his job. His real job is to bring out the beauty of the smiths art. Properly polished, the complexity of the construction is revealed. Improperly polished, the blade is ruined.

A woodcarver makes a saya (scabbard) for the sword. Each saya is custom carved out of wood from the ho tree. The actual blade is required, as the carver will use it as a template to make a properly fitting saya.

A jeweller makes the habaki, the small but critical metal piece which is constructed to fit exactly on the blade next to the tang, and provide the snug friction fit which keeps the blade from rattling in the saya.

Further craftsmen make the finishings. There can be separate craftsmen for the tsuka (handle), tsuba (handguard) and menuki (hilt ornaments).

9a. How many layers in a Japanese sword? [toc]

It depends on the smith. Shinganae is generally folded about 10 times, resulting in about a 1000 layers. Kawagane is folded anywhere from 12 to 16 times, depending on the smith and the metal he is working with, and so could have from 4000 to 65000 layers.

9b. What are the different types of Japanese swords? [toc]

Generally, the swords are classified by length. A daito is a sword with a blade longer than two shaku ( shaku = 11.9 inches ). A wakizashi is between one and two shaku in length, and a tanto is less than one shaku.

There are lots of other names. The most common one, katana, refers to the style most people have seen, a daito which is worn stuck through the obi (belt) with the edge up. A tachi is an older style, slightly longer and more curved, worn slung on cords with the edge down, usually used in a calvary style. A no-dachi is a bigger tachi, with a very long handle, worn slung over the back for battlefield application. A ko-dachi is a different word for a wakizashi, or short sword. A chokuto, or ken, is a very old style straight sword.

10. What sort of weapons are used for practice? [toc]

The usual weapon used in Kendo is the shinai. It is constructed of 4 pieces of split bamboo. The tip of the shinai is covered in leather; the four staves are held apart by a t-shaped piece of rubber. The staves are held together at the opposite end by a long leather handle. The handle is round rather than oval like a real katana. A leather lace tied in a complicated knot about a third of the way from the tip keeps the staves from spreading too far apart. A string runs down one stave -it signifies the dull edge, or back of the sword.

The split construction allows the staves to both flex and compress against each other, absorbing much of the energy of the blow. Attacks which miss the armour cause bruises; nothing more. Poorly maintained shinai can be dangerous - bamboo shinai must be checked and sanded regularly to avoid splinters, and oiled or waxed to help prevent drying out and subsequent breakage. For this reason carbon fibre shinai have become popular. Although expensive and less lively-feeling compared to bamboo, they are virtually maintenance free and last for years. Also, carbon fibre shinai may be purchased with an oval grip, which many people prefer. Previously, only expensive hand-made bamboo shinai had oval grips.

More advanced kendoka use bokken, or wooden swords. Bokken are usually constructed of white Japanese oak, although they can be made of a variety of exotic hardwoods. They are curved and sized like a katana, and the handle is about the same length and oval. Kenjutsu is often practiced with bokken, and in fact kendoka use bokken to practice the kendo kata, which are derived from kenjutsu.

Iaidoka at lower ranks use iaito, which are dull katana. A good iaito at the least has a proper handle with rayskin and cord grip and is constructed strongly enough so as not to be a danger in practice. The more expensive a iaito gets, the more closely it's construction mirrors that of a good sharp sword (shinken).

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