Fight Science! Did anyone watch this?

[imaybehurt]

Hello all
Sorry for the late reply but the life of a goober such as me is busy.
I will do my best to answer your questions all together if I can.
Wish me luck.

I believe that Chi is electro magnetic and has an "aura" (for want of a better word) just as electrical wiring in a house gives off electro magnetic energy so do we, and our wires aren't insulated. hee hee
Personally I don't believe that this "Chi" can effect someone without them being within our magnetic field which is relatively close (under a foot)
I think if people are doing this and getting knock outs etc, it is heavily psychosomatic.
ok Chi is not mystical or supernatural….a unicorn is…….lol
I don’t believe that a person can fly yet but am willing to change my perception if someone can show me a person doing it.
Shooting electricity from our Fingertips? hmmmmm anyone that has ever tried to get into your car during summer in LA I’m sure has been shocked at some point. In some cases, I know that at dusk I have actually seen the light blue electricity jump between my fingers and the car.
Ever taken a polyester sweater off in a dark room? we can make it glow and crackle with electricity. This is natural. Most people just don’t understand therefore we are more than willing to automatically categorize these events into our mystical/supernatural folder.

(1) Yes my punch was more powerful than the bat or crowbar (around 10, 000 lbs)
(2) No it didn't hurt my hand (I can’t figure that one out either)
The idea is to maximize the energy transfer. When you swing a bat the weight/energy is thrown to the end of the bat same as my hammerfist, the bat unfortunately losses a lot of impact energy out the end of the bat and then bounces off.
I try to maximize the “fluid shock transfer” by pulling the fist back towards me just before impact.

I am not trying to discount anybody’s beliefs as I have my own as well.
We must remember that beliefs are merely our congregation of thoughts and ideas that we as individuals hold clos, but it doesn’t necessarily mean that they are true. Even my own. I will hold them close until proven otherwise.
I think that the major problem with the explanation of Qi, Chi, Tao etc is the fact that the names are taken from one language, then roughly translated into others. This forces (in some cases) the real meaning to be lost.

Even in religion people are still fighting over the meanings of the original texts.
So the study of the peace and love of God somehow becomes a battle.
This unfortunately travels into everything else such as the discussion of Chi.

I promise you this I will not force my opinion on you. If you agree then great and if you oppose then that’s fine to. The information will get to the right people regardless.

Thank you all for your interest,

Glen Levy

 

[Stimpson J. Cat]

I have not seen the show, but based on what I have read here, and on what Geln Levy has said, I think I have an idea of what is going on.

First of all, I am a physicist. I am also a martial artist (for about 15 years). That said, I think that one thing people have to keep in mind is that there are different types of striking energy, which are useful for different purposes, and that simply measuring something like an impact displacement doesn't come close to telling the whole story.

I can give an example from my experience with the SCA, which is a group which fights in full metal armor using ratan sticks. Two common types of strikes they use are what I will refer to as a "blow-thru" strike, and a "whipping" strike. The blow-thru strike is what most people would think of as a very powerful blow. The attacker attempts to transfer as much of his body mass into the strike as possible, with a combination of hip rotation, torso rotation, shifting of body-weight (usually forward), and sinking. Likewise the attack usually follows a rather long distance, allowing for maximal time of acceleration. The attacker also strikes "through" the target, rather than bouncing back, stopping on impact, or drawing across the surface.

The result of this, mechanically speaking, is a blow which transfers a maximal amount of momentum into the target. This can be desirable for a number of reasons, the primary one being of course to inflict as much damage on a successful strike as possible, but in addition, the strike is difficult to block, and is likely to disrupt the target's balance, or even knock them down. When delivered against a shield, such attacks also greatly fatigue the defender.

The same principle applies in empty hand fighting. Attacks like a roundhouse kick, or a powerful right-hand punch, work in much the same way. In addition to hitting hard, the attacks will, even if blocked, unbalance and fatigue the defender.

The whipping strike is completely different, though. Here the goal is not to maximize the transfered momentum, but instead to maximize the kinetic energy of the strike. For those not familiar with the difference, kinetic energy goes as the square of the velocity, whereas momentum is proportional to velocity. For example, a baseball thrown at 60mph hour has much more momentum than a bullent going at 500mph, but the bullet has much more kinetic energy.

This whipping energy is achieved by striking in such a way as to get the tip of the weapon moving as fast as possible, and then snapping back just before impact (usually by stapping the hip and tensing the arm muscles). This snapping motion can greatly accelerate the tip, but actually steals much of the momentum that would otherwise be transfered by the blow. Such strikes would be considered by many measures to be much "softer" than the blow-thru strike described above, but their ability to inflict damage on certain types of targets can be much greater. In my experiences with the SCA, for example, it was whipping strikes which would tend to leave big dents in the armor, whereas blow-thru strikes are more easily absorbed by rigid metal armor. Incidentally, the situation is just the opposite with Kevlar, which is designed to dissipate the huge amount of kinetic energy of a bullet. A bullet will punch right through steal plate armor, and a sharp sword thrust will punch right through kevlar.

I believe that what Glen Levy has described is essentially a whipping strike, and it would not at all surprise me if what was measures is really more a function of the total kinetic energy tranfered, than a function of the momentum transfered. After all, in a car accident the time over which the car stops is what is critical. In the car wreck the mass of the dummy is constant, so the real variable is the speed of impact. Airbags, good bumpers, and crumpling car bodies, all reduce the effecting speed of the impact.

It also would not at all surprise me that a well executed whipping strike with a hammer fist could transmit more kinetic energy than a blow from a baseball bat. That does not necessarily mean that it would do more damage to the human body. Likewise, I am sure that I could generate even more kinetic energy from a whipping strike with a ratan stick that weighs less that a quarter of what the bat does. Bats are specifically designed to transmit momentum, not to maximize the speed of the point of impact.

Dr. Stupid

 

[nemesise1977]

here is another way to see how that force can be achived. comon mesurement of impact force in the US is psi or pounds per square inch. so lets say you tag someone with a basball bat with 500 lbs of force and the impact area is a 1/4 inch wide by 6in long section of the bat, the surface area is then 1.5 inches so impact force is 500/1.5 or 333 PSI. now lets say you use the same 500 lbs of force in a two nuckle punch where the survace area is the peaks of the first 2 nuckles the area measures about 1/4 wide by1/2 long on each nuckle so surface area is .25 square inches making the equation 500/.25= 2000 PSI. Because the point of impact is so much smaller the force is actually multilplied because instead of the force being spread out it is focused. Kinda like driving a Nail into a board with a hammer, a large nail requires more force because it spread the force over a greater area vs a smaller nail , this is also why arrowheads, bullets and nails have a smaller end, it magnifieys the force and intensifies penetration power, This is also why a knife stab will amke it through Kevlar while a bullet won't the focused enery on the very small point of a knife or icepick is much more than that of a more blunt bullet. Now if you made a bullet point as small as a knife point it would go through much easier than the knife would.

Same as in the video where the samll point of the knee breaking ribs, you can hit softer but in a much smaller surface area you will have a much greater impast at that point, you hit the correct point things break.

 

[Ashles]

Hello all
Sorry for the late reply but the life of a goober such as me is busy.
I will do my best to answer your questions all together if I can.
Wish me luck.

I believe that Chi is electro magnetic and has an "aura" (for want of a better word) just as electrical wiring in a house gives off electro magnetic energy so do we, and our wires aren't insulated. hee hee

Electricity as trasmitted within our body operates entirely differently from that of how electricity is transmited in wires.
The analogy simply does not work.

Personally I don't believe that this "Chi" can effect someone without them being within our magnetic field which is relatively close (under a foot)
I think if people are doing this and getting knock outs etc, it is heavily psychosomatic.
ok Chi is not mystical or supernatural….a unicorn is…….lol
I don’t believe that a person can fly yet but am willing to change my perception if someone can show me a person doing it.
Shooting electricity from our Fingertips? hmmmmm anyone that has ever tried to get into your car during summer in LA I’m sure has been shocked at some point. In some cases, I know that at dusk I have actually seen the light blue electricity jump between my fingers and the car.

Static electricity is well understood and does not operate by conscious thought.
Are you serious with these points?

 

[Dustin Kesselberg]

Glen. What do you mean you punch with "10,000 lbs"? Do you mean 10,000 psi? If you do then you're telling a tall tale.

10,000 psi is superhuman. I watched the show and no one punched with a psi that high. As a matter of a fact the boxer had a higher PSI than you had and his PSI was somewhere around 1,500 or something like that.


Also, When humans have static electricity it has nothing to do with our bioelectricity. It has to do with the fact we are simply good electrical
conductors. The energy in a static shock comes from the friction caused, Not from our 'bio electricity'.

 

[Kevin_Lowe]

Just to add to Stimpson's excellent post, a trademark trick of Chen tai chi, Hsing I and related martial arts is generating surprisingly powerful strikes with little obvious body movement. Although I can't do it myself, the people who do claim to "get it" and are not woo-woos say that the trick involves a combination of good biomechanics using almost completely extended limbs to maximise internal leverage, and storing and releasing oomph in a manner analogous to snapping one's fingers.

It sounds from Glen's description of what he is doing, and the fact that he says he got the basic idea from tai chi chuan, that this is what Glen does to generate his staggering numbers.

(I will say though that there is absolutely no way that pulling your punch at the last second can increase its power. It might feel that way, but it can't possibly work that way. What Glen might be doing is rotating his elbow down and extending it very slightly just before impact, which could feel like pulling the punch but might increase its power).

Nobody has ever to my knowledge demonstrated the ability to do the trick to a competently resisting target, which is not to say that nobody ever will. However as far as the currently available evidence goes strikes like Glen's are a demonstration technique not a fighting technique.

I think this is why you don't see such strikes, or for that matter the fatalities some people expect from such strikes, in venues like the UFC. The techniques used in the UFC aren't the most powerful techniques, they are the most powerful techniques that can be made to work a high percentage of the time against a competently resisting opponent.

 

[luchog]

Just to add to Stimpson's excellent post, a trademark trick of Chen tai chi, Hsing I and related martial arts is generating surprisingly powerful strikes with little obvious body movement. Although I can't do it myself, the people who do claim to "get it" and are not woo-woos say that the trick involves a combination of good biomechanics using almost completely extended limbs to maximise internal leverage, and storing and releasing oomph in a manner analogous to snapping one's fingers.

What Bruce Lee called "putting your hip into it", or "putting your entire body into the blow". What people who dismiss things like the 1-inch punch don't seem to realize is that for most people, punching involves a relatively small part of the body, very few muscle groups. Those who are better at delivering strikes are those who are able to involve more of the body in the strike, put more of their physical force behind it. Bruce Lee had simply trained to the point where he was able to leverage much more of his body, focus more of his overall physical force into his strikes than the average untrained, or moderately-trained person is able to.

Along with that, there is also the issue of focussing the transfer of kinetic energy, and knowing the precise method of striking that will alow the maximum amount of that energy to be transferred to the target. I've seen others with a similar amount of training and experience replicate the 1-inch punch very effectively.

And observing it, it is clearly not a push, the dynamics are considerably different. And since it appears to rely entirely on a compliant target, it strikes me (sorry) as being, in itself, rather useless as a combat strike; but rather as a demonstration of the value of the sort of leverage and focus training that does create effective combat techniques.

 

[dakotajudo]

I haven't seen the NG show myself, but I have collected some references, relating to striking force, that may add to the discussion.

Ed. It seems I haven't posted enough to post URL, so, citations the old-fashioned way:

Atha, J., Yeadon, M., Sandover, J., and Parsons, K. (1985). The damaging punch. Br Med J (Clin Res Ed)., 291:1756–1757.
Olsen, P. and Hopkins, W. (2003). The effect of attempted ballistic training on the force and speed of movements. J Strength Cond Res, 17(2):291–8.
Walilko, T., Viano, D., and Bir, C. (2005). Biomechanics of the head for olympic boxer punches to the face. Br J Sports Med, 39(10):710–9.

The first and third are freely available as a download from PubMed, the other may require a subscription.

I'd be curious so see how the forces measured in these studies compare to the forces measured in the show.

 

[Stimpson J. Cat]

luchog,

Just to add to Stimpson's excellent post, a trademark trick of Chen tai chi, Hsing I and related martial arts is generating surprisingly powerful strikes with little obvious body movement. Although I can't do it myself, the people who do claim to "get it" and are not woo-woos say that the trick involves a combination of good biomechanics using almost completely extended limbs to maximise internal leverage, and storing and releasing oomph in a manner analogous to snapping one's fingers.

What Bruce Lee called "putting your hip into it", or "putting your entire body into the blow". What people who dismiss things like the 1-inch punch don't seem to realize is that for most people, punching involves a relatively small part of the body, very few muscle groups. Those who are better at delivering strikes are those who are able to involve more of the body in the strike, put more of their physical force behind it. Bruce Lee had simply trained to the point where he was able to leverage much more of his body, focus more of his overall physical force into his strikes than the average untrained, or moderately-trained person is able to.

Just to clarify: The so-called "1-inch punch", and the whipping strikes I mentioned (which I belive is what Glen Levy was describing), are very different things. The body mechanics, circumstances of use, and resulting effects, are all very different.

Along with that, there is also the issue of focussing the transfer of kinetic energy, and knowing the precise method of striking that will alow the maximum amount of that energy to be transferred to the target. I've seen others with a similar amount of training and experience replicate the 1-inch punch very effectively.

And observing it, it is clearly not a push, the dynamics are considerably different. And since it appears to rely entirely on a compliant target, it strikes me (sorry) as being, in itself, rather useless as a combat strike; but rather as a demonstration of the value of the sort of leverage and focus training that does create effective combat techniques.

I strongly disagree about it requiring a compliant target. On the contrary, the great thing about the mechanics behind the 1-inch punch is that it allows one to make effective attacks from positions where normally he would be unable to, and from which the target neither realizes that he can be effectively attacked, nor has any real possibility of trying to defend the attack.

Incidentally, those body mechanics also translate into weapons use, allowing for weapon strikes well within what would normally be considered the optimal range of the weapon.


I also very much disagree with the idea that whipping strikes require a compliant target, or cannot be used effectively in combat. Again, these strikes all have situations which they are useful for. Often times one notices that a particular attack cannot be effectively used as an opening attack, and thus incorrectly assumes that it is useless.


Dr. Stupid

 

[Kevin_Lowe]

I strongly disagree about it requiring a compliant target. On the contrary, the great thing about the mechanics behind the 1-inch punch is that it allows one to make effective attacks from positions where normally he would be unable to, and from which the target neither realizes that he can be effectively attacked, nor has any real possibility of trying to defend the attack.

As always, link a video or cite a fight where someone has used a one inch punch in this fashion or I will remain skeptical.

I also very much disagree with the idea that whipping strikes require a compliant target, or cannot be used effectively in combat. Again, these strikes all have situations which they are useful for. Often times one notices that a particular attack cannot be effectively used as an opening attack, and thus incorrectly assumes that it is useless.

I said that the Chen/Hsing I mechanism has never been demonstrated to be effective against a competently resisting opponent that I am aware of. I am agnostic about what you call whipping strikes, although it wouldn't surprise me if it turned out that bare-handed whipping strikes just aren't much good at stopping an angry human.

 

[Stimpson J. Cat]

Kevin Lowe,

As always, link a video or cite a fight where someone has used a one inch punch in this fashion or I will remain skeptical.

I've used it in weapon sparring. My opponent trapped my sword arm against his torso with my hand approximately between the stomache and rib cage. By turning my body I was able to line up my arm and shoulder properly, and got about an inch or two of space between my hand and his body. I then did the punch at about 1/2 strength (we were just sparring after all). He lost his grip and had a nice bruise there afterwards. Had it been full strength I am sure I would have broken a rib.

Now I am sure that there are many people out there who can do this punch much better than I can, but I was still able to make it work.

I said that the Chen/Hsing I mechanism has never been demonstrated to be effective against a competently resisting opponent that I am aware of. I am agnostic about what you call whipping strikes, although it wouldn't surprise me if it turned out that bare-handed whipping strikes just aren't much good at stopping an angry human.

I can't really comment on the Cheng/Hsing I mechanism, as I am not familiar with it. The only place I have ever seen bare-handed whipping strikes used is in limb destruction type techniques, where you strike the attacking limb while defending the strike. In such cases the goal is not to "stop" the opponent, but to damage the attacking limb, and the benefit of the whipping strike is not that it somehow does more damage than a normal strike would, but instead just has to do with the mechanics of how the strike is combined with the defense. Basically whipping strikes add options. From any given position, there are a finite number of ways to generate power for a strike, each one places limitations on the targets you can effectively attack. So the more ways of generating power you have, the more options you have.

The same goes for techniques in general. People who look at some particular technique, and say "that is less effective than technique X", or "that technique won't work in any of the following situations...", is really missing the point.



Dr. Stupid

 

[Kevin_Lowe]

I've used it in weapon sparring. My opponent trapped my sword arm against his torso with my hand approximately between the stomache and rib cage. By turning my body I was able to line up my arm and shoulder properly, and got about an inch or two of space between my hand and his body. I then did the punch at about 1/2 strength (we were just sparring after all). He lost his grip and had a nice bruise there afterwards. Had it been full strength I am sure I would have broken a rib.

Now I am sure that there are many people out there who can do this punch much better than I can, but I was still able to make it work.

This is, sad to say, your stock standard MA anecdote. It happened in semi-contact sparring, it is unverifiable, it was a one-off event and the effectiveness of the technique in practise is pure speculation ("Had it been full strength I am sure I would have broken a rib"... Why are your sure? How are you sure?).

I can't really comment on the Cheng/Hsing I mechanism, as I am not familiar with it. The only place I have ever seen bare-handed whipping strikes used is in limb destruction type techniques, where you strike the attacking limb while defending the strike. In such cases the goal is not to "stop" the opponent, but to damage the attacking limb, and the benefit of the whipping strike is not that it somehow does more damage than a normal strike would, but instead just has to do with the mechanics of how the strike is combined with the defense. Basically whipping strikes add options. From any given position, there are a finite number of ways to generate power for a strike, each one places limitations on the targets you can effectively attack. So the more ways of generating power you have, the more options you have.

Full-contact competition tends to darwinise those kinds of "limb destruction" techniques entirely from what I understand. They don't stop an opponent who has their blood up when they work, and they leave you open to get hit when they don't. That's why boxers and MMAers evade or absorb strikes rather than trying to block them with "limb destruction" techniques.

The same goes for techniques in general. People who look at some particular technique, and say "that is less effective than technique X", or "that technique won't work in any of the following situations...", is really missing the point.

It's not a matter of looking at it and taking a guess at when and how it might (or might not) work, it's a matter of whether there is any evidence anybody can make it work against a competently resisting opponent.

 

[pipelineaudio]

99.99999% of the time of the UFC fights (not many) that I've seen, it comes down to a strength contest.

I see some cool grappling moves once in a great while, but punching and kicking seem like theyre some sort of ceremonial thing before the guys do their on the ground strength contest

I have seen dudes in real life fighting each other with "chop saki" (TMA from too much tv shows) techniques, but not usually too convincingly

I have no doubt from personal full on fight for your life stuff that traditional karate blocks work, and work VERY well, so I dont see why it would be so much of a stretch to think the punches and kicks might work.

I never had the power to put behind a punch, and never really learned to kick, so I cant say

 

[Kevin_Lowe]

99.99999% of the time of the UFC fights (not many) that I've seen, it comes down to a strength contest.

I see some cool grappling moves once in a great while, but punching and kicking seem like theyre some sort of ceremonial thing before the guys do their on the ground strength contest

To some extent this is simply the truth, because strength matters a great deal in real fights. To some extent you are missing the element of skill in grappling because you don't have the eye for it yet. If you don't know what you are looking for then skilled grappling is often hard to distinguish from a couple of musclebound people hugging.

This is especially so when both participants are good grapplers. It's much more fun and dynamic when a good grappler is wrecking someone who is clueless, but you have to go back to the early UFCs to see that because nobody in the modern events enters without a strong grappling skill set.

I have no doubt from personal full on fight for your life stuff that traditional karate blocks work, and work VERY well, so I dont see why it would be so much of a stretch to think the punches and kicks might work.

They work well against the totally untrained haymaker, but that is about it. Against jabs and crosses the traditional karate blocks will just get you hurt, which is why you never see them used in full-contact karate competitions.

I never had the power to put behind a punch, and never really learned to kick, so I cant say

There's no doubting the power of full-contact karate exponents. (Woo-karate exponents, the majority, are a different matter). Kyokushinkai karateka can and have competed with thai kickboxers with a limited amount of success, which is saying a great deal.

 

[Wudang]

Every time I hear someone argue that leg muscles are stronger than arms so kicks are stronger than punches, I ask them how they push their car if it's stuck in snow. Do they stand on one leg and push with the other? If I want to take down a door I don't kick it, I shoulder it. That way I can use my leg muscles and others better.

 

[Stimpson J. Cat]

Kevin Lowe,

This is, sad to say, your stock standard MA anecdote. It happened in semi-contact sparring, it is unverifiable, it was a one-off event and the effectiveness of the technique in practise is pure speculation ("Had it been full strength I am sure I would have broken a rib"... Why are your sure? How are you sure?).

Well, it is still an example of being able to use the technique on an uncooporative opponent. And I never claimed that this single example was proof of anything. It is exactly what I said it was, and example of using the technique effectively against an uncooporative opponent. And it was effective. As for me knowing that I would have broken a rib, that is based on my observation of the effect the blow did have, and my knowledge of how easy it is to break the lower ribs. I have done it before accidentally, it doesn't really take much.

That said, the effectiveness of the technique in practice is hardly "speculative". First of all, I would not even call it a technique. It is a mechanism for generating power, which can be used for a variety of techniques. Second, the fact that it does generate significant power is quite easy to demonstrate. The fact that this power can be generated from a dynamic position (as opposed to having to take time to carefully "line things up"), is also easy to demonstrate. Given those factors, whether or not it can be used effectively in a fight is simply a function of whether you find yourself in a situation where generating power in that way may be useful.

Full-contact competition tends to darwinise those kinds of "limb destruction" techniques entirely from what I understand. They don't stop an opponent who has their blood up when they work, and they leave you open to get hit when they don't. That's why boxers and MMAers evade or absorb strikes rather than trying to block them with "limb destruction" techniques.

I disagree. Fighting with other highly skilled martial artists is what tends to "darwinise" them. You don't fight a guy in a bar swinging a bear bottle at you the same way you would fight a boxer. One of the first things a fighter learns in sparring (if his training hasn't already ingrained it into him), is how to make it very difficult for such techniques to be used against him.

There is a lot more to martial arts than just full-contact competition.

It's not a matter of looking at it and taking a guess at when and how it might (or might not) work, it's a matter of whether there is any evidence anybody can make it work against a competently resisting opponent.

Well, my example above is such evidence. The fact that it was not full contact does not change this. Also, I am not even sure it makes sense to talk about "resisting" for this type of thing. I am not talking about a hold or throw here, nor about a joint-lock. Nor am I talking about some sophisticated nerve strike or balance disrupting technique. I am talking about punching somebody hard enough to cause damage. If I can demonstrate that the punch is hard enough to inflict damage, and that it can be successfully executed in a dynamic situation, then what more needs to be said? It is an effective way to generate power for a strike. Whether or not you can use it effectively depends on you, just as it does for any other way of generating power for a strike.

As for whether it has ever been used in full-contact competition, I have no idea. I don't watch full-contact competition. Then again, if it was used in such a competition, I doubt people watching would even recognize that it was. It looks like a push, and what's one more bruise after the fight is over?


Dr. Stupid

 

[Wudang]

The reason the sledge hammer wasn't able to go through all of the bricks and the man was is because with the sledgehammer you can't continue to put pressure all of the way through the strike, All of the pressure is put into the initial blow and thats it. However the man was able to do the strike and then continue to put all of his bodyweight down onto the brocks to continue crushing them. Don't forget he was over 250lbs.

I haven't seen the show but that's how woo MA-ists break concrete slabs. Remember if you put concrete slabs on the ground they need an even layer of sand to support them. To break one, support it either end, slap your hand on the slab (which deadens your hand a biot and settles the slab) then slam your weight down.

 

[Big Les]

One disappointing thing about the show was the JKD guy doing the samurai thing, and not the fat guy, was really looking forward to him ripping that dummy apart.

Yeah, it was sad that they went with Mr Buff and Hunky, over the guy who really knew how to use a katana. In fact the whole edged weapon bit was a real let-down - instead of debunking the myths surrounding the katana (as a type, it's no better than any other type of sword) they perpetuated them by either ignoring the outrageous ones (silk scarf and cannon-barrel cutting for example) or by implying that the katana was way ahead of the other (eastern) swords they showed. It descended into subjective argument - any type of sword could have cut the ballistics gel like that - it's technique more than anything.

 

[geni]

If I want to take down a door I don't kick it, I shoulder it.

Might work depending on how much you weigh but kicks around the lock seem to be the recomended technique. Never needed to remove a door but from the demotiltion I've done during canal restoration my experence is that feet work the best.

 

[Wudang]

Kicks around the lock work best for pretty cheap yale locks IIRC. Even better if you stand on a chair and kick just below the lock.