"Principles of judo explained by science"

This videoclip gives an easy to follow and simple biomechanical classification of a number of principles that are at work in a jûdô throw.




Please, note that this is a simplified view, more intended to explain a number of concepts defined by Kanô. This is not the same as a thorough scientific analysis of what a throw is. In reality there is not really a separate kuzushi phase that is separate from the throw. But a thorough explanation of what is at work in a jûdô throw is a complicated matter. So take (and enjoy) this clip for what it is, with that caveat in mind.

Nice animation. Kano would be thrilled. Though, it's a bit odd to have a "scientific" analysis performed in such a martial vacuum i.e. detached from the key element of interaction between tori and uke. Tori's throw is a reaction to uke's action rather than tori's move against a non-resisting uke or worse, a move regardless of uke's resistance. In other words, a throwing action is a sequential event so reference to the previous stage should be made otherwise it sends a wrong message. Eye-catching CGI can't compensate for logical flaws.

Brainjutsu wrote:Nice animation. Kano would be thrilled. Though, it's a bit odd to have a "scientific" analysis performed in such a martial vacuum i.e. detached from the key element of interaction between tori and uke. Tori's throw is a reaction to uke's action rather than tori's move against a non-resisting uke or worse, a move regardless of uke's resistance. In other words, a throwing action is a sequential event so reference to the previous stage should be made otherwise it sends a wrong message. Eye-catching CGI can't compensate for logical flaws.

You will have noticed that my post started with the words: "Please, note that this is a simplified view".

When you scientifically analyze things, in particular complicated things, you have to strip them of confounding variables, and there are many. Throws are typically applied in a jûdô match, or randori or yaku-soku-geiko. In such a situation, there are huge confounders. The actual throw though is a throw. Some of what you describe isn't the throw itself but debana, or opportunity or at least the chosen moment as to when the throw is applied, but isn't the throw itself. Much of the training of throws in jûdô is also applied in simplified situations such as uchi-komi or static practice.

One of the aims of describing or posting things here is also that people can still more or less understand it, so that there is some sense in writing the post. The more one deviates from simplified situations, the more it will be over the head of many readers, making the post somewhat senseless. Scientific analysis in addition to learning to simply "know how things work" also has the merit that it can contribute to facilitating skill transfer (= teaching) or improvement of a competitor's technical flaws. This is important not just for the individual itself, but also because traditional jûdô teaching as well as some concepts are not accurate, which possibly contributes to why skill transfer in jûdô is difficult. Some of these problems have to do with Kanô's own limitations. They have inflated jûdô with some errors, one of the most important ones being that Kanô's approach to kuzushi was based on an approach that considered the human body as a rigid body, which obviously it is not. Other errors, or perhaps more accurately 'flaws', have to do with the absence of a third dimension in its teaching of kuzushi, which is also what our friend NBK has picked up on in his thread on the Vitruvian Man model. People need to understand that Kanô was primarily as pedagogue, not a scientist, and this is likely one of the reasons why there are some flaws in jûdô not just as a discipline but also as a pedagogical model. Both happô-no-kuzushi and the gokyô are two of jûdô's most important didactic models. Are they ideal ? Given the difficulties in skill transfer in jûdô which we teachers are confronted with every single practice session, the question can be raised whether ... if Kanô's understanding of the underlying sciences would have been more accurate if this could not have led to a more effective didactic approach. Is the gokyô the ideal teaching approach, or would a gokyô or model that would have been based on accurate scientific understanding possibly be more pedagogically-effective than the current one which is merely based on perception of progressive difficulty of ukemi ?

For the rest, the teaching approach in Kôdôkan jûdô is, understandably, focused on "chopping up" pieces, such as a throw in several components. That works to some extent, but there too there is room for discussion. Kôdôkan typically uses three sequences (tsukuri, kuzushi, kake), some use others, I use seven, and a pure scientific approach is even different from that. As with most things that involve science, an important task is to not perform the science purely for the science, but ensure its effective application in actual teaching, practice, or competing.

Cichorei Kano wrote:

Brainjutsu wrote:Nice animation. Kano would be thrilled. Though, it's a bit odd to have a "scientific" analysis performed in such a martial vacuum i.e. detached from the key element of interaction between tori and uke. Tori's throw is a reaction to uke's action rather than tori's move against a non-resisting uke or worse, a move regardless of uke's resistance. In other words, a throwing action is a sequential event so reference to the previous stage should be made otherwise it sends a wrong message. Eye-catching CGI can't compensate for logical flaws.

You will have noticed that my post started with the words: "Please, note that this is a simplified view".

When you scientifically analyze things, in particular complicated things, you have to strip them of confounding variables, and there are many. Throws are typically applied in a jûdô match, or randori or yaku-soku-geiko. In such a situation, there are huge confounders. The actual throw though is a throw. Some of what you describe isn't the throw itself but debana, or opportunity or at least the chosen moment as to when the throw is applied, but isn't the throw itself. Much of the training of throws in jûdô is also applied in simplified situations such as uchi-komi or static practice.

One of the aims of describing or posting things here is also that people can still more or less understand it, so that there is some sense in writing the post. The more one deviates from simplified situations, the more it will be over the head of many readers, making the post somewhat senseless. Scientific analysis in addition to learning to simply "know how things work" also has the merit that it can contribute to facilitating skill transfer (= teaching) or improvement of a competitor's technical flaws. This is important not just for the individual itself, but also because traditional jûdô teaching as well as some concepts are not accurate, which possibly contributes to why skill transfer in jûdô is difficult. Some of these problems have to do with Kanô's own limitations. They have inflated jûdô with some errors, one of the most important ones being that Kanô's approach to kuzushi was based on an approach that considered the human body as a rigid body, which obviously it is not. Other errors, or perhaps more accurately 'flaws', have to do with the absence of a third dimension in its teaching of kuzushi, which is also what our friend NBK has picked up on in his thread on the Vitruvian Man model. People need to understand that Kanô was primarily as pedagogue, not a scientist, and this is likely one of the reasons why there are some flaws in jûdô not just as a discipline but also as a pedagogical model. Both happô-no-kuzushi and the gokyô are two of jûdô's most important didactic models. Are they ideal ?  Given the difficulties in skill transfer in jûdô which we teachers are confronted with every single practice session, the question can be raised whether ... if Kanô's understanding of the underlying sciences would have been more accurate if this could not have led to a more effective didactic approach. Is the gokyô the ideal teaching approach, or would a gokyô or model that would have been based on accurate scientific understanding possibly be more pedagogically-effective than the current one which is merely based on perception of progressive difficulty of ukemi ?

For the rest, the teaching approach in Kôdôkan jûdô is, understandably, focused on "chopping up" pieces, such as a throw in several components. That works to some extent, but there too there is room for discussion. Kôdôkan typically uses three sequences (tsukuri, kuzushi, kake), some use others, I use seven, and a pure scientific approach is even different from that. As with most things that involve science, an important task is to not perform the science purely for the science, but ensure its effective application in actual teaching, practice, or competing.

The most important part of your explanation involves the very last paragraph (and in particular the last sentence). Too much "science" can muddle the understanding for most humans. As one, among the many of common folk, it would make no difference to my learning if you could produce a scientist who could explain the throw in a purely scientific method--- with equations that computed the exact direction, speed and motion of the atoms comprising tori and uke. We operate in world where approximations do us the most good. And its not perfect, but works. However, I would contend that most of our understandings will continue to come from close approximations. And as teachers we need to make the most of this valued teaching tool even if its not perfect.

afulldeck wrote:
The most important part of your explanation involves the very last paragraph (and in particular the last sentence). Too much "science" can muddle the understanding for most humans. As one, among the many of common folk, it would make no difference to my learning if you could produce a scientist who could explain the throw in a purely scientific method--- with equations that computed the exact direction, speed and motion of the atoms comprising tori and uke. We operate in world where approximations do us the most good. And its not perfect, but works. However, I would contend that most of our understandings will continue to come from close approximations. And as teachers we need to make the most of this valued teaching tool even if its not perfect.

My response to that would be that learning poses a number of problems. Firstly, not everybody learns in the same way, probably because of different brain wiring. It remains unclear to what extent personal preference and culture are a factor in this. Nevertheless, I regularly (at university) have had students who would claim that they were visual learners, while others do not make such statements. That does not necessarily mean this is true, but of course I have no objective means for assessing this. Visual means certainly sometimes are "more fun", but something "more fun" does not mean learning is better although having that fun tend to imagine it does. Some people can learn by simply seeing teacher doing something like that whether jûdô, or dancing or drawing. Others clearly can't. Some need a lot of explanations, others don't at all.

Take music for example. Traditional music teaching stands with learning to play scales, and then finger exercises, etc. That is common, but does it have to be that way ? Why does music teaching not commonly start with playing music ? Certainly some autodidactic people have started in some very different ways, and some have reached remarkable heights.

The next issue is the depth of learning. While people learn, not everyone learns things at the same depth. Some are very superficial, others are not, some memorize, others understand. What I have always perceived in my (university) students as significant discriminator between the final outcome is the extent to which a student can do what I call diagonal learning and making connections. The really best and likely also most intelligent, can do this spontaneously, the average student seriously struggles with it. It's like comparing a standard low-budget computer with a computer build around a top processor and maximal memory; the first one may simply freeze up and not do anything anymore, the other one will do it promptly with hardly more effort than a simply calculation.

We see something in jûdô too and across the whole scale of dan-ranks. I have known high dan-ranks who have been around forever, are respected, have been in any committee, have been teachers for dozens of years, did all their time-in-grade, have won medals, yet don't know a whole lot about jûdô. I have known teachers at the Kôdôkan who when you would ask them a couple of questions about jûdô would go numb. And yet at the other end of the scale, you have people like Okano, Hirano, Daigo, who have these profound insights, skills, creativity that is totally different from others who have been in jûdô the same time.

Why ? Is this a consequence of personal limitations, or does teaching or the lack of teaching quality they've had play a significant role in this ? Why can't most people do uchi-mata ? Is it because their low motor skills, or is it because they did not have the appropriate teaching and teachers ?

These are important questions, and science does have a place in this, an important place even.

Imagine your uchi-mata sucks. Your sensei who is at least 124 years old demonstrates it and it works flawlessly, and so you ask "sense, my uchi-mata, no good, what am I doing wrong ?" So your sensei answers: "Grashopper, you are not using your ki. Use your ki and uchi-mata will follow naturally".

You are working with your friend, and your friend has perfectly learnt uchi-mata from your sensei, and you being frustrated wonder, how is that possible. So you ask you friend "Satô-san, my uchi-mata, no good, but you have learnt well from sensei. How is that ? What is your secret, how did you become so good at it?"

So, your friend answers: "afulldeck-san, before, my uchi-mata like yours, no good. But sensei told me to use my ki, so I used my ki, and now, uchi-mata good"


This scenario is not unthinkable in jûdô and from a teaching-point of view, well ... your friend Satô was able to learn it by a simply comment from your sensei, yet, you did not and in fact have no idea what is really wrong with your uchi-mata, and how on earth to have or use ki.

This is a problem, since ki does not exist as physics force. Everything that happens in martial arts is nothing more and nothing less than Newtonian mechanics.

You are in despair, but suddenly, you hear some noise, and yes, it is professor Stephen Hawking in a motorized wheelchair and dressed in jûdôgi who rides his wheel chair on to that tatami to the black board on the wall. He grabs a piece of chalk, and scribbles some mathematical formulas on the board and says: "afulldeck-san, blimey but your uchi-mata before was not very stellar. This is why".

Will your uchi-mata now be better ? Probably not. But, this example does not prove that science fails to contribute to your learning of jûdô. Both the ki-example and the Hawking-example suffer from the same problem, namely the lack of translating that material into something that is individually usable applied to your situation, and both failed to actually 'teach'. They explained, but they did not teach. Your first teacher failed to exlain what ki, is how you develop it, how you apply it and how it relates to uchi-mata, and professor Hawking failed to translate his mathematical formulas into usable practical information for you. But, Hawking was not wrong. There just was a teaching and communication problem. It is there where the skills of an accomplished teacher come in. In jûdô this problem is extremely prevalent. It is the same issue we see at the elite level, where time after time national coaches are selected because they have won themselves some Olympic, world or continental medal, something almost entirely irrelevant and useless with regard to their task. They can't teach and they are clueless about the weaknesses of their athletes and lack the insight and skills to change the process.

Of course in individual teaching it is easier to be more flexible than in group teaching where you have to create and average teaching strategy, too slow for some, too quick for others. And despite all this we should not forget that the teacher can only facilitate; at the end of the day it is still the jûdôka him-/herself who has to undergo the development and who has the responsibility to practice in order to achieve that goal. Even the best teacher will fail to optimally transfer skills to a student who does not do his/her part of the deal.

The topic of video is to show how the principle of “softness overcoming hardness” is applied in judo. Two applications of a throwing technique are shown, one hard and the other one soft. Whether a throwing technique can be shown detached from uke’s action is debatable. I don’t think it can because judo is essentially a way of adjusting to opponent’s input and gokyo a way of learning variables in it. Basic idea such as “when pushed-pull and when pulled-push” clearly imply the causality. In other words, no uke's action - no tori's throw. The video is clearly short on that element. A simplified model would portray such input in a one-dimensional manner, for example, but shouldn’t remove it altogether. Still, given that the demo seems to be aimed at entertaining rather than educating, the omission is tolerable (the basic conclusion after watching it is more likely to be “how cool”, than “let’s try it”).

The biggest flaw with the presented video, however, is that it implies that judo is about tori choosing “soft” over “hard” while in fact is should be that uke’s “hard” is countered by tori’s “soft”. The overall idea is that uke’s “hardness”, being “softly” redirected against him by tori, will do the “hard work” for tori. The underlying condition is that tori cannot do the same amount of “hard work” on his own initiative. Otherwise, he wouldn’t opt for delayed initiative, which is a much harder and riskier form of fighting.

@CK, you are very correct to point out that learning style is also a problem. I tend to think of knowledge acquisition as a kind of dyad relationship (teacher-student) whose meiosis ends with new judoka, engineer, musician etc. The 'quality' of the teaching component and the 'quality & attributes' of the student comprise the end result. In short, the end result could be good, mediocre or be bad depending on the quality and attributes brought to the dyad.

@brainjujitsu, you can still pick up a sandbag and throw it. Most people, especially, those new to judo think in those terms. However, I believe you are correct (aka no uke action-no tori action) when you are talking judo. Further, I think a harder example would be to show how a big (tall) man would throw a smaller man using only the judo principles in the video (without falling to the knees).

CK, is this similar to calling psychology a science? Or, justifying "political science"? Bother are pseudo science.

afja_lm139 wrote:CK, is this similar to calling psychology a science?  Or, justifying "political science"?    Bother are pseudo science.

Not sure what you mean; neither psychology nor politology are exact sciences, but physics is, and jûdô is nothing but the application of Newtonian mechanics: lever actions, conservation of momentum, torque, potential and kinetic energy, heat dissipation, and forces. The actions that take place involving throws probably can be best modelled using Hamilton-Lagrangian Equations and Hamilton's Action Principle, the Jacobi form of the Least Action, and the Poinsot geometrical description of free forces of motion of a body. This isn't exactly laymen's stuff hence why before a general public of jûdôka one has to enormously dumb things down, which is exactly what is done and what is the merit of te video.

afulldeck wrote:@brainjujitsu, you can still pick up a sandbag and throw it. Most people, especially, those new to judo think in those terms. However, I believe you are correct (aka no uke action-no tori action) when you are talking judo. Further, I think a harder example would be to show how a big (tall) man would throw a smaller man using only the judo principles in the video (without falling to the knees).

Yes, the sandbag approach is actually quite common in today's practice. But that’s caused by judo’s logical incoherence and the nature of sport matches rather than by the intention of judo practitioners. When you join a judo club and stand on tatami, your options are rather limited. In fact, applying more force into techniques is quite often a necessity, not a cheap way out of the skill.

I originally learned judo from the self-defense aspect where uke’s action was a given fact. In that sense, most of gokyo-no-waza worked just fine in learning to recognize “how the attacker wanted to be thrown” as my instructor used to say. Yet, in sport match you essentially have two tori fighters competing to make uke of each other. By coming from the same martial background and conditioned by sport rules, they simply have to force out gokyo throws in any possible way. Also, unlike self-defense where it’s the effect of the throw that counts (along with other things), the sport competition is about making a throw itself. It’s questionable if such substitution of goals for means is what judo was meant to be or if Kano himself cared about the difference when developing judo, but that’s another matter. Judo throws are consequence of the specific environment, one way or the other.

In that sense, your dilemma about having a bigger man throw a smaller one in the fashion showed in video, can by answered in this way: why would he even go for such option at all given the circumstances?

Best regards

Brainjutsu wrote:

afulldeck wrote:@brainjujitsu, you can still pick up a sandbag and throw it. Most people, especially, those new to judo think in those terms. However, I believe you are correct (aka no uke action-no tori action) when you are talking judo. Further, I think a harder example would be to show how a big (tall) man would throw a smaller man using only the judo principles in the video (without falling to the knees).

Yes, the sandbag approach is actually quite common in today's practice. But that’s caused by judo’s logical incoherence and the nature of sport matches rather than by the intention of judo practitioners. When you join a judo club and stand on tatami, your options are rather limited. In fact, applying more force into techniques is quite often a necessity, not a cheap way out of the skill.

I originally learned judo from the self-defense aspect where uke’s action was a given fact. In that sense, most of gokyo-no-waza worked just fine in learning to recognize “how the attacker wanted to be thrown” as my instructor used to say. Yet, in sport match you essentially have two tori fighters competing to make uke of each other. By coming from the same martial background and conditioned by sport rules, they simply have to force out gokyo throws in any possible way. Also, unlike self-defense where it’s the effect of the throw that counts (along with other things), the sport competition is about making a throw itself. It’s questionable if such substitution of goals for means is what judo was meant to be or if Kano himself cared about the difference when developing judo, but that’s another matter. Judo throws are consequence of the specific environment, one way or the other.

In that sense, your dilemma about having a bigger man throw a smaller one in the fashion showed in video, can by answered in this way: why would he even go for such option at all given the circumstances?

Best regards

Why? To learn real judo of course. The biggest gorilla on the tatami never needs judo...

afulldeck wrote:

Brainjutsu wrote:

afulldeck wrote:@brainjujitsu, you can still pick up a sandbag and throw it. Most people, especially, those new to judo think in those terms. However, I believe you are correct (aka no uke action-no tori action) when you are talking judo. Further, I think a harder example would be to show how a big (tall) man would throw a smaller man using only the judo principles in the video (without falling to the knees).

Yes, the sandbag approach is actually quite common in today's practice. But that’s caused by judo’s logical incoherence and the nature of sport matches rather than by the intention of judo practitioners. When you join a judo club and stand on tatami, your options are rather limited. In fact, applying more force into techniques is quite often a necessity, not a cheap way out of the skill.

I originally learned judo from the self-defense aspect where uke’s action was a given fact. In that sense, most of gokyo-no-waza worked just fine in learning to recognize “how the attacker wanted to be thrown” as my instructor used to say. Yet, in sport match you essentially have two tori fighters competing to make uke of each other. By coming from the same martial background and conditioned by sport rules, they simply have to force out gokyo throws in any possible way. Also, unlike self-defense where it’s the effect of the throw that counts (along with other things), the sport competition is about making a throw itself. It’s questionable if such substitution of goals for means is what judo was meant to be or if Kano himself cared about the difference when developing judo, but that’s another matter. Judo throws are consequence of the specific environment, one way or the other.

In that sense, your dilemma about having a bigger man throw a smaller one in the fashion showed in video, can by answered in this way: why would he even go for such option at all given the circumstances?

Best regards

Why? To learn real judo of course. The biggest gorilla on the tatami never needs judo...

Can you educate me on this real judo you speak about???    

afulldeck wrote:

Brainjutsu wrote:

In that sense, your dilemma about having a bigger man throw a smaller one in the fashion showed in video, can by answered in this way: why would he even go for such option at all given the circumstances?

Why? To learn real judo of course. The biggest gorilla on the tatami never needs judo...

You mean something like this:)



Actually, I was thinking about a bigger (and taller) man knowing judo and using it. However, the video above shows what softness vs. hardness really means or should mean. It's not how you setup the lever.

"Real Judo" is when you are having fun doing it.

Koga should have had no chance in Ne waza.

If a Judoka is less than half of the weight of your own, you can simple turn him around. I am near 50 and we have a very high level international Judoka -60kg in our club and he has no chance in newaza against me, simple I have more than double weight and a lot more power. In Tachi Waza it's much more difficult to use pure strenght.

.

Anatol wrote:Koga should have had no chance in Ne waza.

If a Judoka is less than half of the weight of your own, you can simple turn him around. I am near 50 and we have a very high level international Judoka -60kg in our club and he has no chance in newaza against me, simple I have more than double weight and a lot more power. In Tachi Waza it's much more difficult to use pure strenght.

.

There are two parts to your post, namey whether "Koga" would not have any chance in newaza, and whether that can be extrapolated to "any judoka other than Koga".

Your suggestion has limitations that deserve some exposure. Those limitations are twofold:

1. that the newaza skills of both jûdôka are somewhat comparable.
2. that newaza is limited to osae-komi-waza

These limitations are important, and the more the newaza skills of one jûdôka outweighs the other the less that becomes true. Koga is not known for having newaza skills that are as exceptional as his tachi-waza, but I doubt that they are mediocre, as generally the Japanese are less focused on just one part of jûdô than Westerners. In any case some jûdôka do or did newaza skills that were as exceptional as their tachi-waza. Okano Isao is such an example. Let's not forget that the man won the All Japan Championships twice and add also a silver medal to it. I think that when dealing with someone like Kashiwazaki who too has extraordinary newaza skills that most much heavier jûdôka would know very well they would stand little chance. Particularly in order to choke someone, differences in body mass are a lot less important.

I think that there are also some examples of this in BJJ. I bet that the best among the Gracies too were able to defeat much heavier opponents in grappling.

While I am not twice as heavy as my head-sensei in Kyôto who is in his 80s, I am pretty convinced that I would not stand a chance against him in newaza. He is considered probably the greatest newaza expert in Japan and until a couple of years ago still competed in the masters. He never lost a match in that, and neither did in the Continental masters in which he participated, defeating every single opponent with ippon and in newaza. He is one of the old surviving Kôsen jûdôka and a former sparring partner to the legendary Kimura. When I started training in Kyôto my eyes went open wide essentially realizing that in the West we knew nothing about newaza, and the club I left when I went to Kyôto was actually a newaza club.

But you are correct when it comes to osae-komi-waza, and that can also be scientifically proven. The reason is that biomechanically osae-komi-waza is something entirely different from nage-waza. Osae-komi-waza mechanically is nothing else but pressure, and pressure can be overcome if the other person can generate significantly more pressure. Don't forget though that shime-waza and kansetsu-waza too are totally different from osae-komi-waza as they are lever actions of which the efficiency is increased by exerting them on particularly suited locations on the body.