Knife defenses: Death by Disarm

One of our ongoing R&D initiatives is to explore the design space around aikido-based techniques and training methods to respond to a knife attack (tanto-dori). Tanto-dori has been an integral, but not heavily emphasized component of Aikido since since the early days of the art. It’s not a major focus for most aikido practitioners. No martial art can excel at everything and each style (and dojo) has its areas of specialization.

In light of the technical challenge of seeking effective aikido based responses to more realistic and sophisticated knife attacks and the pervasive nature of knives in today’s society, we’ve been excited to explore this niche area in greater detail. Especially since we have the privilege of being able to learn from some of the world’s finest knife technicians.

One such individual is Jeff Imada, a martial artist master that has trained directly under Guro (Sensei) Dan Inosanto for over four decades. Jeff has trained in a wide range of martial arts, but has deep specialization in Filipino arts that have very mature knife and dual weapon wielding systems. Jeff’s attacks and offensive tactics look nothing like what we’ve all seen in traditional aikido-based knife practice.

If you don’t have time read this entire post, you must at least watch this video. You’ll see how a basic aikido-based disarm works against a skilled knife fighter. It doesn’t end well for me.

Keep in mind that Jeff Imada is a legendary martial arts master with over 45 of experience. The average knife wielder won’t move like this, but the video reveals a stunning display of what the weapon can do.

It’s too early in our research to have any kind of well-formulated aikido-based techniques or training methods to share. However, we do feel confident outlining some general principles that may provide valuable context for tanto-dori practice in the dojo and may save your life if you ever find yourself facing a real attacker with a knife.

Thoughts on Traditional Aikido Knife Defenses

Traditional aikido knife disarms are usually based on attacks that would symbolize a samurai using a tanto to penetrate an opponent’s armor. In these training forms, the attacker generally makes a single committed cut or thrust along one of three lines of attack – a shomenuchi cut, a yokomenuchi cut, or a thrust. After a single attack that conforms to one of these three lines of attack, the nage (defender) will usually move off the line and transition directly into a joint lock based disarm or throw, like kotegaeshi or gokyo.

We believe these training exercises are useful and do have value. They teach timing and entry angles and build the skill to transition smoothly into a range of techniques. These exercises also enhance our empty handed movements. However, expecting a real knife attack to conform to these attack patterns can lead to highly undesirable outcomes – whether from a skilled or unskilled opponent.

Here are four general principles to be mindful of for aikidoka seeking a deeper understanding of the nature of the short blade:

1. Escape is the Best Option

A knife is a very difficult weapon to defend against. It’s elusive and deadly. Those who have deep experience with the weapon always highlight the risk of a knife encounter and tell defenders they can expect to be cut.

It’s important to realize the controlled and engineered nature of our knife disarm practice methods. These training methods have value in the context of our overall development as aikidoka, but don’t be overconfident in your ability to get a disarm to work against an active opponent. If the option is available, running is almost always the best choice.

2. Don’t Force a Disarm

When defending against a knife, don’t focus on a disarm. Disarms are high risk and low priority. Higher priority objectives are to isolate the weapon away from your vital areas and to gain initiative over the opponent via atemi (vital point strike) and / or kuzushi (balance breaking). Disarms should be attempted only when an opportunity presents itself, in the flow of the engagement.

“Don’t chase after something that’s not there.” Jeff Imada

Josh gets to a successful disarm position after using hand movements to clear two prior attacks.
Josh gets to a successful disarm position after using hand movements to clear two prior attacks.

3. Don’t Fixate on the Weapon

A common mistake when facing an armed opponent is fixation on the weapon. Having tunnel vision and focusing exclusively on a weapon causes one to lose sight of other threats (like a grab or strike) and to compromise their situational awareness.

At higher levels as aikidoka, we practice tachi-dori – sword disarms. From this practice, we know that fixation on the blade can cause positioning and timing errors. The issue is even more magnified with a knife because it’s a one-handed weapon. The attacker’s other arm is free to attack, defend, or pro-actively shut down your defensive responses.

While awareness of the weapon is imperative, it’s just as important to track the opponent’s entire body. This insight brought about a paradigm shift for me.

With both of Josh's hands fixated on the knife, Jeff uses his free arm to apply an ikkyo control that shuts down the disarm attempt.
With both of Josh’s hands fixated on the knife, Jeff uses his free arm to apply an ikkyo style control that shuts down the disarm attempt.

4. Expect Non-Standard Lines of Attack

If you’re only trained to defend against an overhead strike or a 45 degree angle or straight thrust, you may have problems dealing with an untrained attacker’s wild strikes or a trained attacker that has fluency with 12 or more lines of attack – some of which create very surprising attack vectors.

Our Raw Research Material

In an effort to promote knowledge exchange, we’ve decided to begin making some of our raw research material available in The Lab, a new section of Ikazuchi.TV One of the pieces of source material we’re now contributing to The Lab is a video with Jeff Imada sharing kali-based insights and principles of knife disarms.

We extend our most sincere respect and gratitude to Jeff Imada and the Inosanto Academy for their openness and generosity.

Group photo at Jeff Imada's "show and tell" session at Ikazuchi Dojo.
Group photo at Jeff Imada’s “show and tell” session at Ikazuchi Dojo.

This article is being co-published with the kind permission of Josh Gold Sensei of the Ikazuchi Dojo. The original article appears here.


Josh Gold

Executive Editor of Aikido Journal, CEO of Budo Accelerator, and co-founder of Ikazuchi Dojo.


  • The responses Josh started were all right for the knife HAND. There was no thought of immediate balance break. No thought of atemi. No thought of checking the knife arm up where it isn’t going nearly as fast.

    I think you need to start with a blocking counter strike, a mix of Saito Sensei’s and Nishio Sensei’s responses.

    I had a student come in who was an old Vietnam veteran Special Forces. He talked about a knife attack that cut four or more of your main arteries while you were just trying to catch up with the knife hand. I wanted more information to practice a response, but I think he has gotten sick and hasn’t been back.

    Perhaps one of the best responses will be an irimi with really strong atemi. That artery cutting attack looked extremely dangerous.

    This video the knife was clearly visible. I think most knife attacks, you won’t see the knife till you are already bleeding from the first cut. You may still not see the knife.

    I am not in any way claiming to be an expert. These thoughts are coming from watching and listening to others experiences. I try to teach a good bit of knife take-aways and to continue to look for / get more knowledge of various attacks and devise responses for them. It needs to be ongoing education.
    Tom Huffman

  • Excellent. Now as homework take an average kitchen knife and, say, a watermelon or pumpkin. We usually apply small muscle movements in the kitchen. With a large muscle movement, especially a stab, see how effortless it is to cut the vegetable. Precise? Maybe not, but precision isn’t all that important in stabbing. Taking this out of the kitchen, consider how our usual atemi, which are not usually that powerful, become important if you have any sort of blade in your hand. I saw a nice Japanese kid, black belt, have a practice knife stuck through his forearm in a demo at the old SF Turk Street school. The edge was round, but the point still worked fine. He finished the kotegaeshi and got the knife. Then he then got first aid and an ambulance to the hospital. If you escape a knife attack uninjured, God was really on your side. As noted in the article, and assuming you notice the weapon at all, don’t fixate on it. In fact if you get a technique on the “off” side, that might be easier. Yes you might be slashed on the way to completion. You may not notice it. And the old Roman rule of thumb was a foot of slash is about as bad as three inches of stab. Oh. Blood is slippery. If, as is likely, your hands get bloody your grip won’t be as secure as you are used to. Is there good news? Yes. In the US there are lots of knives but little real expertise in their use. There’s more good news. In the unlikely event that you have a problem with a knife master, he’s unlikely to announce that (in this corner, champion of the Manila Knife Matches…). So, just be yourself. If you’ve trained well, you may live.

  • Thoughts on knife attack. As I often teach, kata form are not realistic. Neither are prearranged attack or defense. Aikido are not realistic, only your reaction is. However the question remains. How to withstand a skilled knife attacker without injury. And why would you be in such situation. Second as mentioned in the video, none of them gives 100 percent. Any outcome would be highly theoretical.
    In the end it’s all about who draw first blood.

  • Stan:

    Excellent article. Very salient points.

    Having put a little, but very serious, time in with an Escrima teacher many moons ago, it became VERY clear that empty-hand against a knife wielded with even a modicum of skill combined with deadly intent is virtually hopeless.

    It is a ‘last ditch alternative’. And even then, to even nudge the “odds against” just a little in my favor, I had to think way out of the Aikido ‘Box’.

    Chairs, rolled up magazines, articles of clothing, thrown objects, ‘dirty tactics’ … anything and everything had to be employed. And even then, the outcome was almost always multiple slashes, cuts, and punctures regardless.

    Don Angier, the Yanagi Ryu Aikijujitsu Soke, used to encourage us to train in empty-handed techniques AS IF uke held a knife … or even two. It adds a keenness of awareness and sensitivity to ‘Ma-ai’ and ‘Suki’ that is usually lacking in Taijitsu training.

    Distance – Timing – Openings.

    My own take is to integrate “Aiki” awareness with the Waza of an established knife fighting tradition for the best of what must be called a fighting chance in a “Very, Very Bad Day” scenario.

    There is a reason for the expressions:

    “You can’t be a Boy Scout in a knife fight.”

    … and sure as hell …

    “Don’t bring a knife to a gun fight.”


    Know which one you’re doing and why. Inform yourself. Be clear about your choices. Train intelligently.

  • This is FANTASTIC! Much thanks to Mr. Imada, Gold-sensei, and the Ikazuchi Dojo for this gem. The knife presents a fascinating challenge in real combat. Below is a link to an old tanto-dori seminar conducted by Mitsugi Saotome-shihan (with the late, great Kevin Choate as first uke). He takes a lot of time demonstrating how complex dealing with a knife can be.

    Saotome-shihan dazzled a crowd at an early All Japan Aikido Demonstration in the seventies with a randori featuring knife wielding ukes! Eeeyouch! 🙂

  • The aforementioned knife randori featuring young Mitsugi Saotome-shihan in 1973 can be seen here:

    He makes a lot of space, then uses a lot of atemi and a lot of irimi. I’m betting there were plenty of window-rattling “KIAI!” too. Obviously technique and tactics would change drastically under less than ideal circumstances such as the open, deliberate, and classic attacks seen here, but it’s still fantastic budo!

    Thanks, nevertheless, for helping us with a realistic demonstration of the problems with a very skilled attacker in short range. Something to consider….

  • Spot on Jeff Imada! Ossu! It’s a whole different world when training with trained knife, and other blade weapons, martial artists! The training as usual need a major overhaul in reality! Cudos to Gold Sensei for bringing that experience into his dojo! Peace!

  • Thank you Josh and Jeff for addressing tanto training with a tactical perspective, rather than the purely ritualistic
    approach usually taken in aikido. As you point out, tsuki practice in aikido mimics a knife thrust on a 14th century battlefield – where a single full force thrust was needed to pierce armor. This attack allows for beautiful, artistic, and relatively easy martial arts practice, but has little relation to any edged weapons threat a student is likely to face today.

    I totally agree that evasion and escape – rather than disarming – is the realistic approach to this training. A tactical retreat if one has a moment – to escape /or grab any weapon is a better response than choosing to stay and fight unarmed. Usually a weapon can be obtained with a 5-10 second all out run: Outside – a branch / stone/ dirt/ sand/ trash can/piece of trash/etc. Inside – a chair/table/lamp/mop/broom/desk/fire extinguisher/etc. And a knife wielding assailant on the run after you loses a lot of his balance and other tactical advantages.

    A few recommendations for giving tanto practice more integrity and realism:

    Critically important tools for every practice are KIAI and ATEMI. Just poking the eye of a 250 lb. fellow put him
    out of action for several minutes – you can’t stab what you can’t see.

    Do not present the knife prior to attack – most people attacked with a weapon report “it came out of nowhere”
    or “I never saw the knife before I got cut.” So practice immediately recognizing a weapon is present when a palm
    or hand is subtly hidden. A knife being advertised is to threaten – not to attack.

    Josh’s position to attempt kotegaeshi wrist throw was the common position that works fine for modern “acrobatic
    aikido” but was not the Founder’s aiki budo POSITION. Close and AT UKE”S SIDE (ever heard of Tai No Henko !)
    we are not only safer, and more able to take his balance, but most important > we do not loose contact with the
    weapon hand as it retracts to attack again (sorry no single full body thrusts these days as in classical Japan.)

    Students must be told the TRUTH because information is power – When confronting an edged weapon attack
    “expect to be cut.” Martial arts illusion-fantasy-mythology has no place on the training floor, leave that stuff to
    performers doing demonstrations. And let students know you can get all cut up and still function very well.
    With a four inch cut right to bone across my forearm – I was fully functional, until the adrenaline wore off a half
    hour later. Fear (adrenaline) thank God, increases the clotting factor of blood tremendously. Ignore being cut !

    Attempting to react to some attackers’ movements is nearly impossible, often with delay results. Real life does
    not happen in slow-telegraphed- predictable ways as in most dojo training. We must stop the passive “waiting
    – reacting – blending” which is the hallmark of modern aikido. The Founder almost always – moved FIRST.
    This forces the attacker to react US, putting HIM at a disadvantage > momentarily nullifying any tactical
    skills he may possess.

    Perhaps most important is POISE – neither freezing / nor over reacting. The vast majority of knife weilding individuals use the knife to THREATEN – NOT ATTACK. To fight someone who demands the paper or plastic in my wallet is a gross over reaction in my opinion. That may not sound very macho for an ex-cop – martial artist, but I am not willing to kill or die over material stuff. Only to protect life. But this element of mental stability within us which O-Sensei called our EARTH element must be nurtured and strengthened with continuous/rigorous SHUGYO. The Founder made this a huge part of his training – we should follow his lead.

    Tom Collings
    Long Island Asian Studies Center Dojo,
    Bellmore, NY

  • Entirely agree with these comments. Tanto dori against realistic knife attacks is a very good way of showing up weaknesses in aikido technique and yes focus on the knife, lack of effective irimi and atemi, and struggling to complete a technique that is not working are all problems I’ve noted. Looking forward to hearing more on this.