Revisiting Measurements for Training Weapons

In a previous post from a few years back, I spoke about the importance of measurements for one’s weapons according to the martial system being studied. There, it was mentioned how necessary it is to wield weapons that have proper dimensions according to our body type when we are beginners. For this post, we will take this same subject and look at it from another perspective, where I discuss about the strong points of training with weapons of irregular dimensions in kobudō (古武道, Classical Japanese martial arts) as an advanced student.


When first starting out, a student is required to acquire training weapons that fit their body type in order to study the lessons correctly. After some time has passed where the student has become familiar with a particular weapon of a standard length, they should next come out of their comfort zone and handle one of a different length. Sometimes this can be impromptu during class, or other times the focus of the lesson can be placed on this point. There are many reasons behind this. For starters, to further understand the principles for said weapon, whether it be a sword or staff, one has to be exposed to conditions that teach us lessons that go beyond just the physical. Distance, timing, and positioning are just some of the principles that require being explored under not-so-usual conditions.

An example of bokutō (wooden swords) of different lengths

For starters, against an adversary with a sanjaku dachi (三尺太刀, a Japanese sword that measures about three feet), a rokushaku bō (六尺棒, six-foot stick) provides a great reach that allows the wielder to perform ashibarai (足払, leg sweep) from a safe distance. Yet, when given a sanjaku bō (三尺棒, three-foot stick), you won’t have the same advantage as before. Still, with further training and having a deep understanding of the principles of one’s art, you can still perform an ashibarai to defeat an opponent without getting cut down.


Sometimes the same set of kata for one particular weapon is used to teach how to use another weapon even if it’s a different size. This is another challenging point that can further support an martial system’s ideology across a different span of weapons. For example, some traditional schools in Japan have used the kata for the naginata as a means to learn how to wield the yari. Others have used the kata for the katana to understand how to utilize the kusarigama. each of these weapons have unique traits that provide interesting results, especially in the case of the kusarigama; a sickle with a flexible chain & weight takes a great amount of understanding and control if pitted in the same scenario where a katana would be used.

Next, there are those kata where one performs with a katana, but then later does it with a much longer sword like an ōdachi, or with a much smaller one like a kodachi. All three are categorized as swords, but with varying lengths. For an advanced student, one of the greatest challenges here is understanding the strengths & weaknesses of the weapon in hand, and how it affects not only the control (or lack of) they may gain, but also how their opponent will react based on how each weapon is manipulated.


When an adequate amount of training has been put in, an advanced student should begin to develop the ability  to use anything that comes into hand. Looking the development of different martial systems in Japan’s history from the 1500s onward, many incorporated the study of multiple weapons in the form of sōgō bujutsu (総合武術, martial system featuring numerous disciplines). This not only encouraged bushi (武士, warriors) to be familiar in many different skills, but to be resourceful enough to use anything that they could get their hands on, including their opponent’s own weapon. The same mentality remains in various martial arts schools even today.

Many countries have very strict laws against carrying weapons, even those for self defense purposes. While it may seem impractical to study classical systems that specialize in the use of the yari, kusarigama, and so forth, this isn’t truth. Much of what is learned can be applied to common tools and items we find around ourselves everyday. An umbrella substituted for a sanjaku bō, a shovel used in place of a yari, or even a belt wielded like a kusarifundō are but examples of adapting one’s training for self-defense in today’s contemporary world. With a thorough understanding of the principles necessary for this through consistent training, it is possible to naturally use any common item in your environment as a weapon without getting caught up in small details such as being the “correct” length with the iaitō used in training, and so on.


In conclusion, working with weapons of different dimensions during training has its merits for advanced students. This can range from handling same-type weapons of varying lengths to using a specific to learn another different weapon type. In the end, a student should be able to go past form & structure of a particular weapon and grasp a deep understanding of the principles behind what make it work. Achieving this, that student will be able to reach the outcome they so desire despite the length of said weapon being slightly off of what would normally fit their body type.

Discerning Measurements for Training Weapons

Great care is necessary when studying weapons in martial arts. In the beginning, there are specific forms or drills one must go through in order to understand the characteristics of the weapon that is connected to the ryuha¹, or style of martial system, one is training in. One of the challenging points to ensure correct study is obtaining a training weapon proportional to your body type. For this post, we will look at how the characteristics of weapons (i.e. measurements, material, etc.) are preserved by traditional schools and the hurdles that come with this, the ups & downs of dealing with manufactures that follow the “one size fits all” model, and how one should go about to training with weapons that match us properly.


A good martial arts school will ensure that new students obtain a training weapon suitable for them, whether they are buying it or not. For Japanese traditional martial systems this is commonplace. For example, there are numerous types of systems for kenjutsu² (sword techniques), each with their own unique philosophies. Some may specialize a slightly shorter blade length that requires ashisabaki³ (evasive movements with the feet), or a much longer blade where maai⁴ (distance) and chōshi⁵ (timing) are key components. Others may utilize a nitōryū⁶ (2-sword style) system, where two swords that are wielded in each hand are a different size from each other. At any rate, when wielding a sword that does not fit your school’s criteria, unforeseen adjustments will be made, which will prevent a new student from grasping the principles of the particular kenjutsu being studied.

Example of training kusari fundo I’ve made over the years. Each can have a variation in length, weight, size of the weighted ends, etc.

During my years as an assistant instructor at my previous dojo, I was adamant regarding using training weapons that were proportional with those who attended my class. In one case, the monthly theme was a weighted chain called kusari fundo⁷. We used rope versions for safe training. Since I was already making these rope versions for my own training, I did so for those who attended my class to ensure they learned correctly. I had to measure each student’s arm length so to have their rope kusari fundo tailor-made to them.

There is an interesting story⁸ that deals with the weighted chain. A man by the name of Charles Gruzanski, a military officer stationed in Japan during the 1950s, was accepted as a student in Masaki ryu Manrikigusari jutsu⁹ under the 10th successor at the time, Nawa Fumio. One of the challenges that his teacher had to deal with was finding an appropriate chain size for Charles, as he was a tall man with large hands. The weighted chains that Fumio had just were too short, which would’ve made studying the techniques difficult to comprehend. Through some searching, he finally tracked down a chain from a different style that was large enough for Charles to use. This story is an important reminder that appropriateness in weapon size is necessary in the beginning of one’s training.


There can be a fascination regarding information in ancient documentations, such as scrolls and manuals. Those that have descriptions of weapon dimensions, for example, are important details critical to the identity of a martial system. However, one must take caution in following these details too literally. When a training weapon is being prepared based on specific dimensions, it still needs to be adjusted based on the student’s body proportion.

3 pics that illustrate different lengths in staves used in Japanese martial arts. When first studying bōjutsu that requires the rokushaku bō, choosing the right length is critical. Click on each pic for descriptions.

Let’s look at a very common weapon used in Japanese martial arts, which is the rokushaku bo¹⁰, or 6-shaku staff in English. A shaku¹¹ is an old measurement unit used in Japan. This “6-shaku” is a length that serves as a standard, a rough measurement for a staff that should be around or slightly taller than your height. In the past, this length would be appropriate for most Japanese martial artists that were above 5 feet, but it was not unusual for the staff to be made shorter for accommodation purposes. Likewise, those who are much taller than 6 feet (especially in western countries) would need a staff slightly longer. In cases like these, access to having weapons custom made according to a practitioner’s needs is a must.


Shopping for one’s training weapons can be at times difficult. Going to a common martial arts store in your neighborhood that sells everything at only one size is limiting unless you are at that perfect height where everything fits your body type (around 5″6 & up). When shopping around, especially online, what you should look for from retailers is those that A) provide multiple sizes, B) provide customization services, or C) custom make their weapons.

Stores that offer multiple sizes of a particular training weapon is very convenient. Not only does it make finding one that fits you quickly, but this is also convenient for practitioners of all ages. For example, some stores may offer a wooden daito¹² (a standard sized sword) in 3 sizes: large, medium, and small. This ensures that no matter which size you select, it is proportionally designed, from the blade down to the handle. Those needing a smaller size daitō will not need to substitute with a wooden kodachi, which is naturally designed as a one-handed short sword¹³.

Some retailers may offer a customization service, whether they do it on-site or can have it done by another party. This is good when small adjustments are needed, but don’t necessary need to be redesigned from the ground up. Looking at the rokushaku bō as an example, it may be possible to have one adjusted in length in the case where a shorter one is needed.

Here is a comparison of 2 bokken, or wooden swords. The bottom one is a custom made version of the sword that is used in one of the ryuha I study, Togakure ryu. I was given the dimensions as it is said to be written in that system’s scroll, but had to make slight adjustments when getting it designed in order to match my body type.

Possibly the best option is to shop from a retailer who has training weapons custom made. Not only is it possible to have the dimensions tailored to your liking from the smallest detail, but can go as far as craft it and make it unique just for you. While this can be a great option, it can also be more pricier, as time, cost of materials, and labor goes into custom making training weapons. Quality control for custom made weapons tends to be very high, so if money and time is not an issue, then this is a great route to go.


As a rule, it is important to train with weapons that proportionally match. Finding what matches the practitioner is a task that can be handled by the teacher, as it will ensure little to no errors when purchases are made. However, when this has to be in the hands of a student, the best choice are from retailers that give many options that can fit one’s needs.

1) 流派

2) 剣術. An older name related to fighting techniques with a sword. The modernized system of kendo (剣道) derives from this.

3) 足捌き

4) 間合

5) 調子

6) 二刀流

7) 鎖分銅

8) You can read the full story, and more about Charles Gruzanski’s life story in Japanese martial arts at “Tru-Flyte Martial Arts Memorial Website“, which is maintained by Robert C. Gruzanski.

9) 正木流万力鎖術. Manrikigusari is another name for a weighted chain.

10) 六尺棒. Usually translated as 6-foot staff in English, thus most are sold as so. However, in reality 6 shaku does not equal to 6 feet.

11) 1 shaku = 11.93 inches.

12) 大刀

11) 小太刀. A big difference between a daitō and a kodachi is that the handle of a daitō is long enough for 2 hands to grip, while a kodachi’s handle is long enough for only one hand. Size difference in handle makes it difficult, if not impossible, to practice kenjutsu that requires a normal sword, such as a daitō.