There is something that many martial arts have in common. This similarity deals with the fundamental structures we assume with our bodies during combat, and how it can dictate our positioning against an opponent. From my own experience, along with cross-training with and conversing with others, I’ve learn that this fundamental structure is very basic in nature, but is a root support even for advanced instructions. While the approach may differ from one martial art system to another, the end result is generally the same.

This article will discuss this from a kobudō point of view, although I’m sure those from different systems will be able to relate. 2 fundamental body structures that are prominent are “ichimonji” and “hira ichimonji”.

Ichimonji (一文字) in Japanese means “straight line”. While the attitude of the body depicts this, the underline principles speak on it much more. In kobudō, kamae, or postures, that use this body structure generally have one leg forward, and the other leg behind. The front leg’s toes are usually facing forward, while the back leg’s toes are pointing outward, almost 90 degrees. Examples of kamae that are used that greatly represent this linear body structure are Ichimonji no kamae, Katate Seigan no kamae, and Kōsei no kamae.

The strength of this ichimonji, or “straight line” body structure is that it dictates moving forward linearly in a slimmer profile. In application, one can punch or block on a linear path, and have a longer reach because the upper body turns to the side. The slimmer profile makes it easier to be a smaller target, with the ability to slip by and evade oncoming attacks.

The next fundamental body structure, hira ichimonji (平一文字), describe objects that are straight laterally and appear “flat”. In combative scenarios, this shape can be referred to as “squaring up”. In kobudō, postures that use this body structure have us facing forward with our shoulders and hips aligned, and our feet pointing forward at an angle. Examples of kamae with this body structure include Hira Ichimonji no kamae and Hoko no kamae.

Since we are wider with a Hira Ichimonji body structure, there is more rooted stability. It is easier to impose strength, such as during grappling, or show a lack of strength with one’s arms down. It is a more natural body form, meaning movements of all types can be done as well.

Here is an example of how these fundamental structures determine mechanical movement. There is a unique method of movement called shikkō (膝行), which involves walking while kneeling down. We start off in a kneeling position called seiza (正座), with both palms placed on top of the thighs near the hips. Next, we raise our right leg up and put our right foot forward while turning our upper body to the left through our hips. from there, we bring our right knee down to the ground as our entire body slides forward. Lastly, we return back to seiza by pulling our left leg forward next to our right leg, all the while turning our hips to face forward. We repeat this by alternating to our left leg by raising it up & forward in the same fashion. In seiza we have a hira ichimonji structure, but whenever we step forward our body shifts into an ichimonji structure. This is the proper way to do it, for trying to maintain only hira ichimonji structure is unnatural and very difficult. This demonstration of shifting our body into an ichimonji structure is also key for many other skills while in seiza, which includes punching and grappling.

Earlier it was mentioned that each fundamental structure represents a posture. While this is truth for the most part, it is not entirely written in stone, especially since postures are not static poses. In fact, it is not unusual for a posture to have both an ichimonji structure and a hira ichimonji structure. Let’s take Hassō no kamae from Kukishinden ryu Naginatajutsu. When we assume Hassō no kamae with our naginata in hand to our right side, it is not wrong to stand with our left foot forward and upper body turned to the right, or with both feet roughly lined up together while facing forward with our chest. Each variation of this kamae have their advantages, especially when analyzed from a battlefield perspective.

If we look at the ichimonji structure of this kamae, not only does it allow the user to evade an incoming strike from an enemy while setting up for a counterattack, it also makes a person a smaller target while wearing armor, along with using the oosode (大袖, plates of woven armor draped beside the shoulder) as a shield. On the other hand, hira ichimonji structure is beneficial in group formation, for if a group of warriors are wielding naginata, they create a natural barricade against incoming enemies, all the while having the ability to push back with the shaft and quickly delivering a kesa giri (袈裟斬り, diagonal cut) through small motions. There is great versatility with these 2 fundamental body structures in the techniques of kobudō, offering infinite possibilities once well versed in adapting them in our movements.

In closing, these two fundamental body structures are linear, making the concept of them representing a lateral and horizontal line simple to grasp. As many things that are simple in nature, they hold an abundance of value when applied to strategic lessons. This holds true for kobudō, as well as other martial arts.