What Karate Students Should Know About the Japanese Sword

What does a karateka need to know about the Japanese sword? Well, nothing really.

Karate's roots are not in feudal Japan, where the katana was ubiquitous. Yes, there were plenty of swords in old Okinawa, but as an art directed mostly at unarmed combat, karate emphasizes movements and strategies that are, in many ways, incompatible with those used to make the sword an effective weapon.

It's odd and sometimes unnerving to watch karate demonstrations given by sword "experts." Assuming that a person can use a sword just because he or she has experience in karate is like assuming that because your basketball skills are excellent, you'll be a good lacrosse player — they're both sports that use a ball, after all.

In short, karate and swordsmanship are both fighting arts, but there's little in the way of technical or strategic overlap.

Nevertheless, it's useful for the karateka who wishes to gain a wider perspective on combat to know a few basics about the katana. At the very least, the karateka will benefit from having the knowledge needed to distinguish a legitimate sword demonstration from a poor one. In that vein, here are some of those basics.

First, it might seem that the katana, given its fearsome reputation, cuts easily. It does not. Actually, it's technically challenging to cut effectively, especially when comparing the katana to a weapon like a Viking longsword. Given the mass of the heavy Viking blade, if you swing it hard enough, you will inflict injury. You might cut only superficially, but the percussive damage done by swinging that big blade will crush flesh and bone.

To cut effectively and efficiently, a katana must be wielded with its edge perfectly aligned with its spine, which is where most of the mass of the blade is located. (This is why in cross section, a katana looks like a miniature hatchet, with a thick ridge that provides stability and that narrows to a fine edge.)Yes, a Japanese sword will cut even if the edge is not perfectly aligned with the spine. However, if you also factor in armor — or even clothing worn by an enemy — you can imagine how difficult it could be to make a proper cut that inflicts enough damage to eliminate a threat.

For this reason, a fundamental term in sword work is hasuji, which refers to correctly aligning the blade as it moves to the target.

Without good hasuji, the weapon can twist or deflect. Even when cutting soft targets in practice, this can cause wrist injuries.
It's also important to understand that the katana cuts by slicing, by moving horizontally at least slightly, through the target. Swordsmen in Japan sometimes demonstrate this by tapping the edge of their blade against the palm of their hand without doing any damage — so long as they make no pushing or pulling motion at all.(Do not try this! If you pull or push the blade even a millimeter, you'll risk not just a nasty flesh wound but also potential tendon damage.)Different schools of swordsmanship approach this matter of slicing in different ways. Some cut in arcs that pull the sword back just at the moment of contact. Others teach you to extend the arms in a shoving action.

However it's achieved, the result of a well-delivered strike from a katana are gruesome. Skin and the layers of flesh beneath it have a tension that's maintained by muscles. A cut interrupts that tension. Make a batch of gelatin and, when it sets, run a sharp knife along the surface. You'll see the "skin" split and widen. This is what happens when a katana strikes.

Historically, it was discovered that this effect was intensified when a blade had a wider spine that added weight. Old teaching scrolls sometimes use poetic language to describe the result, referring to "scarlet blossoms blooming," proving that even hardened warriors felt some queasiness at the prospect of such horrible consequences.

The aftermath of these cuts — skin split into a wide "V" — meant that wounds healed slowly and poorly, if at all. Photographs of samurai from the final years of feudalism show jagged scars that arc like miniature mountain ranges. They were the lucky ones, in a sense. The more common outcome, aside from bleeding out in a matter of moments if an artery was severed, was a long, hideously painful death from infection.

A fundamental term in sword work is hasuji, which refers to correctly aligning the blade as it moves to the target. Without good hasuji, the weapon can twist or deflect.

Hand someone a katana and ask him or her to swing it using both hands. It's almost guaranteed that the person won't do it effectively. Chances are the top (right) hand will supply the power. Because most of us are right-handed, this propensity is exaggerated even more. Watch videos of people cutting straw mats or bamboo, and you can see this dramatically.

The left hand seems to be just along for the ride. A katana swing, however, is most effective when the left hand generates the power and the right hand guides the movement of the blade. One of the most challenging aspects for teachers to address is to get students to use their left hand and arm to generate power.

Speaking of those videos — the ones that display awesome tameshigiri feats that entail hacking through objects — I once heard a teacher who had just watched such a video say, "This isn't tameshigiri, or test-cutting; it's tameshi-kudaki, or test-smashing."

Yes, it's impressive to see a blade go through rolls of wrapped straw. Likewise, it's impressive to see a hammer smash a walnut. However, the second "feat" isn't terribly productive if you want to eat the walnut's meat, which will be smashed, as well.

The goal of a sword cut is to inflict deliberate, focused damage. One feat that demonstrates this kind of control is cutting a roll of straw placed horizontally so the blade goes through all but the bottom few strands. That allows the roll to break in half yet stay connected. This is control. This is focused energy. It's an example of how powerful a sword can be when used properly — and how delicate is its destructive touch.

Dave Lowry has written Karate Way since 1986. For more information about his articles and books, visit blackbeltmag.com and type his name into the search box.

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