Enter the Ishi-Sashi: Old-Style Functional Karate Strength Training for the 21st Century

The other day somebody asked me how to strength train for Karate. What machines to use, how many sets, how many reps, what muscle groups, what angles, what type of weights… ad infinitum.

So, to that guy and the rest of you hear ye, hear ye:

One thing that many people of today’s Karate world seem to have grossly misunderstood, and sometimes even forgotten, is the concept of supplementary training.

Now, don’t get me wrong here. Cross-training is huge these days, I know, but knowing what, how and when to perform supplementary training (that is; extra training which supplements and ultimately boosts your skills in Karate) is a bit tricky. And it’s more popular in modern martial sports (MMA, Thai boxing, wrestling and such), than in the more traditional martial arts like Karate. We don’t do it because it’s not always “traditional”, right?

Most Karate people might just jog a little, or hit the gym now and then. If even that.

Which is fine.

But not optimal.

So why settle for less than optimal, if optimal happens to be just a few tweaks away? Or just a special tool away?

In this article I’ll give you some advice on how to bring traditional Karate-style hojo undo (supplementary strength and conditioning training) into the 21st century; using one of the most popular strength training tools on the market today.

Rocky Balboa

But first, let’s take a quick stroll down memory lane:

People in the martial arts have always been trying to improve their fighting skills through extra training, whether it be kicking bamboo trees in the hot jungle or punching frozen pigs in a cold slaughterhouse. You know it, Rocky knew it, and the old masters of Karate knew it. I’ve written about this numerous times before by the way, so I don’t make me convince you again.

Strength training and conditioning is essential for every Karate nerd.

But the big question is; “What’s the most optimal way?

Should we hit the local gym, where there’s only useless open-chain machines that exercise completely wrong angles and muscles for Karate? Or should we try some of that cool Crossfit stuff? Billy’s Bootcamp? Tae Bo? Yoga? Elastic bands? Wrist weights? Dumbbells? Ankle weights? Weight vest? Pure body-weight exercises?


Or, yes, sometimes, but not now. Because we need to go back to the roots, check out some of the original training implements used in old-school Karate, figure out how to translate that to the 21st century, and hopefully achieve greatness.

So here’s what I’m suggesting for every Karate man or woman out there:





Why? Here’s why:

  1. Great combination of cardio and strength.
  2. Great solution for busy people.
  3. Comparatively cheap. One tool, hundreds of exercises.
  4. Increases metabolism (6 pack, yes please!).
  5. Not boring and easy (like barbells and dumbbells).
  6. Gives you a complete, full body workout.
  7. It’s fun.
  8. The old masters did it too (explanation below).

Ever heard about ishi-sashi?

If you practise traditional Goju-ryu, I bet you have.


The ishi-sashi, or “awesome stone padlock” as the names translates to, is an old strength training tool from Okinawa (originally from China though) used for training the specific muscles of Karate through highly functional drills and movements. Today most Karate dojo that does hojo-undo (supplementary training) only uses stuff like the chi-ishi, makiwara and perhaps the nigiri-game, but the ishi-sashi mustn’t be forgotten. And this is not only for Goju-people this is for everyone. Shaolin monks too.

I mean, it’s not a coincidence that the kettlebell, the #1 strength training tool of choice for practically every UFC fighter and functional fitness coach today, is almost an exact copy of the ishi-sashi that the old Karate masters used.

They knew something.

It simply rocks too much to not use.

Here’s a pic taken from a video of the ishi-sashi in use, pre-WW2 (that is, before Miyagi Chojun codified his brainchild of Goju-ryu):

Double ishi-sashi to the far right

So what’s the difference between the ishi-sashi and a kettlebell?

See for yourself:

Practically speaking, there’s no significant difference.

You can do the exact same exercises.

However, since there is a larger market for kettlebells today than for old Okinawan/Chinese stones with handles, kettlebells can come in various sizes and shapes. They also vary in weight and material, ranging from 5 to 175lbs and cast iron to sand-filled plastic. Many companies have created adjustable kettlebells with different variations of handles too, some of which can be removed and connected to other weights. Also, for protection, some kettlebells are wrapped in thick plastic and have grips in the handles to avoid damage to floors (and improve safety when swing motions are used).


“So what’s so great about the ishi-sashi, or kettlebell, anyway?” I hear you going. Well, when using kettlebells for Karate training, you can incorporate a wider, longer range of motion, more sport specific movements (read: Karate movements) and the off-centered weight will force you to use more stabilizer muscles (= “belii impoootant” as your Japanese sensei would have said). Using kettlebells teaches you how to absorb the shock from the ballistic movements of the exercises, similar to punching, blocking and kicking.

In other words, good great stuff.

Kettlebell training to more closely mimics the dynamic and explosive movements that are executed in a fight than the traditional push and pull movements used in a body building routine does. With a kettlebell, you can basically mimic several of the moves you’ll perform in a real fight, such as getting up from the ground with an opponent pushing you down, or shifting the body’s center of gravity to take on an opposing force while keeping balanced, throwing somebody down, twisting the hips for pounding somebody’s face in, etc.

In short, you need one.

Right now.

Not only for the historical significance (ishi-sashi = kettlebell), but for the sheer practicality of it!

Mark my words.

To finish this off, I’ll supply you with a couple of great exercise clips you can use, and if you’re interested you can always Karate-ify them even more. Delayed onset muscle soreness (DOMS) guaranteed. Use a kettlebell, but if you want to feel the wings of history flap then feel free to acquire a real ishi-sashi from somewhere. Not necessary, but cool.

Here’s two Karate clips:

And here’s three original Chinese (mostly used in Shuao Jiao) clips:

(compare that last one to the regular kettlebell swing!)

Now get going.

More power to you!

(PS. Oh, you thought the popular “Bulgarian Bag” was a new fitness fad thingy? Think again. In China they call it the Chang Daizi, and it’s old as hell. You Goju-ryu guys are sure to recognize the Ning Zi too, also originally from China. “Nothing is new under the sun”, as the saying goes…)


  • patrick
    great info, by by dummbells welkom kettelbell
  • Fatihsan
    The question is;At what age should a young person begin lifting weights or using Kettle bells?
    • That is a very old debate, actually! Most people begin responding best to strength training around puberty (for muscle hypertrophy) but younger children also benefit from strength training, especially when it comes to developing the nervous system (focus on practising posture, correct technique and such, with lighter weights). There is a popular myth that strength training for children will harm their development, but that has been debunked by several studies; showing that you can start weight training from 5 years of age, even. Scientists also believe there would be fewer sports related injuries if people would start strength training earlier in childhood, as preventive measure. It's very individual too, of course.
      • Randy
        Kettle bells and similar tools, including Indian clubs and chi'ishi, require a high degree of stabilization of the joint via synergists and stabilizer muscles. The latter tend to be smaller and more prone to injury since they are not typically worked as much as the larger prime movers and synergists and lack the endurance that a prime move might have. The body will go with what is strongest, so if the stabilizers are not up to the task, join motion is impaired. In general, functional training is best and safest when stability exercises targeting the rotator cuff and shoulder stabilizers are included as well. Internal shoulder rotation, external shoulder rotation, upper trapezius, rhomboid, and middle trapezius exercises are good places to start. Exercises that encourage or require internal rotation of the arm and protraction (rounding) of the shoulder require appropriate stretching to keep the RC tendons from becoming impinged and damaged.For kids training, care needs to be taken that proper movement patterns are developed before swinging a weight that can force the shoulder to move in ways that damage the stabilizers (primarily the rotator cuff muscles). Stabilizer conditioning programming should be in line with the demands of the kettle bell training- ie, reps, sets, resistance, tempo, intensity and duration. For the stabilizers, start light and regress the other training if stability issues start to appear. Resistance cables/bands are a great way to start this conditioning for beginners, people in need of stabilizer activation and conditioning, and for experienced folks who are in a stability and corrective phase involving lesser resistance and intensity.
  • John
    Jesse, How much did the traditional ishi -sashi weigh? Did its weight vary (as kettlebells do today)? I'd like to understand how much weight the person in the first karate clip is flipping on to the back of his wrist. Too much invites injury. Regards,
    • Actually, John, I've never thought about that! Though I've seen different sizes of ishi-sashi, I've never looked up the actual weight. :/ Maybe some Goju folks can help...?
      • Paul Enfield
        That's Gima Sensei of the Jundokan and those ishi-sashi weigh no more than approximately 15lbs.
      • Ken
        I think the weights went something like "lightest, lighter, light, medium, heavy, heavier, heaviest." :-P
  • Joe
    Sashi usualy weigh between 3 to 5KG (about 6-11 lbs) But it can vary depending on the experience and methodology of the user. One of the big differences is that when using sashi you have to tighten your grip to keep the weight from flapping around. Think of doing military presses with kettle bells while supporting the ball above your hand, not behind it, you would normaly not be able to use the same weight as you would if holding the kettle bell the normal way. Another example and a regular exercise is to do front raises and using your grip to keep the weight in the same position (out in front of you hand) during the full movement (And no cheating, you can't swing the weight up like a front swing. You need to be able to stop the sashi at any point in the motion and keep the weighted end locked out in front).
  • Shureido in Naha sell some pretty cool ishi sashi. I wish my luggage hadnt already been 10kg over or I would have picked some up! I used them at Jundokan for the first time - and yes, they rock!!
  • Next you should explore the nigh-forgotten chi'ishi clubbell connection... and are they the same thing as the Indian Clubs mention in the other comment? Inquiring want to know...
  • John Durning
    To be honest, I can't help but think that kettle bells are in fashion right now. And like any fashion they'll be overtaken in the next few years by the next next big thing. The single most effective weight training you can do is the Snatch and the Clean and Jerk in my opinion. This involves going from maximum effort and tension to complete relaxation and speed and back to maximum effort and tension in a split second. The single fastest movement you'll see the human body doing is the transition from pulling the bar to getting under the bar. Don't know about you but that sounds pretty similar to the way we want to be doing our techniques. Weightlifters have an incredible level of athletisism and don't deserve the reputation that they have for being immobile body builders. Many olympic lifters can outsprint almost any other athlete, particularly over short distances, and can jump higher than almost any other athlete. And the downside? Well, if you commit to learning these lifts then you're commiting to a completely new sport. 6 months to a year minimum is the sort of time frame you're looking at to becoming proficient and it's many years of training after that to master the techniques. Certainly I won't be going back to kettlebells or powerlifting now that I've started Olympic Lifting.
  • WillieMaize24
    John, The blogger at the Expert Boxing website doesn't recommend weigh training for boxing because boxing calls for snapping punches and movements with gravity and with the core muscles, while weight training involves pushing movements against gravity and with the outer muscles. I suppose the same reasons would apply to karate. Jesse, There are a few other things besides kettle bells that can be tried. I'd suggest that someone who wants to cross train do a search for "Systema" or for Brazilian Jiu Jitsu warmups and you'll find lots of exercises that are useful and that might not be taught in your dojo. There's also the Hsing-I San Ti stance. Anyone who hasn't practiced it would do well to be able to hold it for 5 minutes.
  • Jess awesome input! Look into sledge hammers and compare with Chishi! I have both in my dojo. As an adult we should try use hojo undo within every days training, it's really the continuous overload principle, but working to create much more functional strength power and stability. Improves kihon, kata but must influence bunkai most of all, finally to kumite. As a classical practitioner I'm not concerned with periodisation as I train for every days trials. However an athlete may need to consider this for event preparation.
  • vince
    I am planning to buy some clubbells from rmax or some steel clubs from onnit someday. It has a displaced center of mass like the kettlebell, but I heard it is even more challgening to swing around. Also, you can replicate sport movements with the clubbell.
  • Great article...I am buying kettle bells tomorrow.
  • will
    I have question regarding frequency of use. In his book, "Essential Karate" (1979), Sosai Mas Oyama suggested using sashi everyday. His regimen consisted of 12 exercises, each performed for one set of 10-12 reps. Oyama does not specify the weight of the sashi, but if the other posts are taken as truth, an I do take them as truth, then the sashi in the photographs weigh approximately 15lbs. Is everyday too much? Should I space my exercises out over the week?
  • Anonymous1234
    Kettlebells don't have the weight distributed in the same way as ishi-sashi, due to the difference in shape. So exercises may not be exactly the same
  • Alan
    Martial arts-specific movement’s typically should be done with lighter weights. Think of punching with light weights: For pure punching 1-5 lbs suffices. Try it for 3 minutes straight. More than that leads to bad form and shoulder injury. The karate exercises are very specific. If you’re using 25-100 lbs for pure ballistic action you’re asking for trouble. The Eastern Europeans have a lot to offer here. Look up “Enter the Kettlebell.” If you’re unfamiliar with them and belong to a gym take a class that uses them. Or read up and YouTube your way to knowledge. I have seen people fling them across the room by accident. It’s a cannonball with a handle. Swing it into the back of your forearm in an uncontrolled motion and you could end up with a plate in your forearm. These are fantastic full-body tools if you educate yourself. If you don’t you could injure your wrists, shoulders, elbows, and lower back all in a few sets. Start light, and if you feel strain in any motion stop. Use them right and you can end up with a full body strengthening routine including grips, and do upper and lower body plus abs in 30-40 minutes.
  • Dave papwirth
    I have been following you on many platforms and reading your knowledge for some time now, I'm in a transitional period within life now where things are getting better but the dojo I practice shotokan at has taken a severe dip and I've questioned myself about looking for a fresh dojo to start. I am also in a position to be able to subscribe to everything you have available and I'm willing to take the Karate Nerd test again. Thank you sensei

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