Two-handed strikes?

[blindsage]

Yes, the torso pivots around the spine and the two opposite motions of either side cancel each other out.

How does that happen? The kinetic energy of the shoulder hitting the wall just somehow 'cancels' and you don't bounce off the wall? That not really how it works.

With a two handed strike there is no canceling out, but the recoil can be minimized by changing the angle of posture or even the angle of the strike.

There is no cancelling out in either version, the kinetic energy goes somewhere either way, you are in control of where, again, if you understand proper body mechanics. And there shouldn't be any recoil in any strike, the body isn't a gun, you don't have something hitting something else inside your body causing a backward force, you are the hammer. The only time there may be recoil is when you hit a target and the full energy of your hit isn't transferred into the target, but then that would probably be your own fault anyway.

 

[Telfer]

How does that happen? The kinetic energy of the shoulder hitting the wall just somehow 'cancels' and you don't bounce off the wall?

I wasnt referring to the wall scenario...when punching the air for example one side of the torso moves forward and the other side moves back, so the force of both motions cancel each other out.

 

[Telfer]

And there shouldn't be any recoil in any strike, the body isn't a gun, you don't have something hitting something else inside your body causing a backward force, you are the hammer.

The only time there may be recoil is when you hit a target and the full energy of your hit isn't transferred into the target, but then that would probably be your own fault anyway.

There is always an opposite and equal reactive force. When you strike a target you prevent recoil with a stable stance, using the rear foot as a brace against the floor.

 

[blindsage]

I wasnt referring to the wall scenario...when punching the air for example one side of the torso moves forward and the other side moves back, so the force of both motions cancel each other out.

it is not cancelled, it is circular movement of the torso as a whole, if you are moving them seperately, or thinking of them as such it this is not what is happening. If you are moving them as seperate parts, that is a whole other problem all together. If you are punching the air the force of the strike whould be going out, towards or into the target even if punching the air.

 

[blindsage]

There is always an opposite and equal reactive force. When you strike a target you prevent recoil with a stable stance, using the rear foot as a brace against the floor.

But you weren't talking about striking a target, you were talking about shadowboxing basically. If you aren't hitting a target, what is causing the recoil? Why is your back hitting the wall when you throw a two handed hit?

 

[Telfer]

If you aren't hitting a target, what is causing the recoil? Why is your back hitting the wall when you throw a two handed hit?

The contraction of your triceps can be likened to the explosion inside a gun, which forces the bullet forward and the gun backward in recoil.

Your fist is the bullet and your body is the gun.

Except in this case the fist is connected to the body (unlike the bullet) so when it connects with a target the recoil is far more powerful than merely striking the air.

 

[blindsage]

The contraction of your triceps can be likened to the explosion inside a gun, which forces the bullet forward and the gun backward in recoil.

Except that if you are using proper mechanics the tricep is not the source of power your body is.

Your fist is the bullet and your body is the gun.

The entire force of your body should be going into the fist this is why you twist in a boxing style punch, the body is the bullet, not the fist.

Except in this case the fist is connected to the body (unlike the bullet) so when it connects with a target the recoil is far more powerful than merely striking the air.

The 'recoil' comes from not transferring the power properly into your target. The better you get at hitting (understanding body mechanics) the more power goes into your target, and the less 'recoil' you get. The fist doesn't recoil because it's attached to the body, it recoils because it strikes something harder than the force generated, or it's force is actively redirected, not because the body automatically 'recoils' from hitting.

You have a perception of body mechanics that is flawed from the get go. You are either striking with much less power than you are capable of or your understanding of what you are doing is vastly different from what you are actually doing.

 

[Telfer]

The entire force of your body should be going into the fist this is why you twist in a boxing style punch, the body is the bullet, not the fist.

Try holding your arm straight out in front of a heavy bag and hit with the hips as you say.

 

[Telfer]

The 'recoil' comes from not transferring the power properly into your target. The better you get at hitting the more power goes into your target, and the less 'recoil' you get.

There is always an opposite and equal reactive force...its one of the first laws of physics.

So you always get recoil, the trick is to prevent the reactive force from acting on anything but the target...in other words, reflecting it back at the target through the miracle of postural stability.

Imagine a gun held in a VERY strong vise...the force acting on the bullet would be much stronger because of the gun's rock solid immobility.

 

[Chris Parker]

Hi Telfer,

Have to say, you're really off on your understanding here (as a number of others have said). But to put it in the terms you are using here, here we go.

The law you are refering to is Newton's 3rd Law of Motion, the first dealing with inertia, and the second deals with application of force. Pretty important stuff for us to understand and get right. The third law is, as you said, that every action will have an equal and opposite reaction. Unfortunately, you are rather out in where you think that equal and opposite reaction is. And your "wall" experiment is just plain wrong, sorry.

If you strike, as you say, with one shoulder going forward (the striking side, let's say the right here), causing the opposite (the left) to go backwards, then you have lost half of your potential power backwards, and really need to improve your understanding of power generation. Instead, as you strike forward, the balancing force goes back down into the ground through your legs and feet (what most TMA guys and arts refer to as being "rooted" or "grounded"). As we teach it, the pivot point is not your spine, as that results in the aforementioned loss of power, but the opposite shoulder/hip. Think of your body not as a revolving door, but as a gate swinging on a hinge. That way all your body weight goes forward, there is no bouncing off of anything, and you get maximum power generation. And it follows Newton's Laws.

The trick is to prevent the reactive force from acting on anything but the target? Nope, you've kind of lost physics again there. From the sounds of things, you've got a little way to go, so I'd start paying attention to those trying to help you out, sound good?

As to your tricep acting as an explosive force, well, if you are really doing that you will have pretty much no power whatsoever. You are just using a fairly weak muscle in a rather inefficient way, and tensing it which reduces speed, and thereby power. Remember that 2nd Law? F = ma? Force (power in your strike) equals Mass (the weight of your strike, in your case just your arm, in mine my entire body weight) times Acceleration (the velocity or speed of the mass in motion, and by tensing your tricep to provide you with your "explosive power", you are slowing yourself down).

But back to the original topic. Double strikes exist in a number of forms, but the method you have described is rather limited, and not entirely powerful, but looks great in a WWE match. So I wouldn't expect to see it around.

 

[Telfer]

As we teach it, the pivot point is not your spine, as that results in the aforementioned loss of power, but the opposite shoulder/hip. Think of your body not as a revolving door, but as a gate swinging on a hinge.

Well all I can tell you Chris is that what Ive written is nothing new, and you can look it up in detail from some good authorities on the subject.

This pic for example is from page 101 of Nakayama's classic book 'Dynamic Karate'...does it look like the body pivots at the spine?

http://i48.tinypic.com/2cymqsl.jpg

Indeed, and as for the methods of reflecting recoil you can get a broader description of what I've written from a book called 'Martial Mechanics' by Sifu Phillip Starr, chapter 5 pages 31-37 to be exact.

 

[geezer]

Well all I can tell you Chris is that what Ive written is nothing new, and you can look it up in detail from some good authorities...

I really don't know who's right. In fact I seen instructors teach techniques by referencing things that I'm sure are NOT correct from the standpoint of Newtonian physics. Explaining power generation via Ki or Chi for example. But these same guys could really hit. And the instructional models they used helped their students. So Telfer, how is your hitting power? If it's good, I'm not going to waste time arguing with you! Besides, there are a lot of different ways to generate power. It's a little too complex an issue to resolve with words on a forum like this. So I'm happy with whatever works.

 

[Chris Parker]

Well all I can tell you Chris is that what Ive written is nothing new, and you can look it up in detail from some good authorities on the subject.

This pic for example is from page 101 of Nakayama's classic book 'Dynamic Karate'...does it look like the body pivots at the spine?

http://i48.tinypic.com/2cymqsl.jpg

Indeed, and as for the methods of reflecting recoil you can get a broader description of what I've written from a book called 'Martial Mechanics' by Sifu Phillip Starr, chapter 5 pages 31-37 to be exact.

Hi Telfer,

Well, for one thing, I don't teach karate... however karate's power source comes indeed from the twisting of the spine, but not to the degree you were talking about. The rear hand (in a gyaku tsuki reverse punch) is pulled back and down to the hip, but not to the degree that your shoulder is pulled back. Your picture clearly shows that, by the way.

As to reflecting recoil, that should be taken care of by grounding yourself, not twisting around. By understanding the way the mechanics work, you will find that you are not having the force move you back (if you are doing things correctly), so you may have misread that particular book. Small caveat, I haven't read it myself, so it is entirely possible that I would simply be completely disagreeing with the author there rather than yourself. Either way, though, your description is limited and flawed.

Oh, and Geezer, yeah a number of people use concepts such as ki/qui/chi to describe their power source, but you will also find that the mechanics are very well covered as well. By the way, we use both in our schools, as they actually describe different aspects.

 

[Cirdan]

Try holding your arm straight out in front of a heavy bag and hit with the hips as you say.

That was actually quite funny. In a few years you will hopefully look bak at what you wrote and laugh yourself.

 

[KenpoGer]

In my system (Kenpo) you can block and counter an attack at the same time, in my opionion its an very effective way because wasted motion is wasted time.
Why just block or just counter, do both and the fight will end fast.

Kenpo Salute, Timm

 

[Jaspthecat]

In Xing Yi you learn a double palm strike which when combined with a step forward and the right grounding is very powerful.

Practically, I think it would be best used as a shove eg when you are pushing someone away from you to encourage them to back off.

 

[blindsage]

Try holding your arm straight out in front of a heavy bag and hit with the hips as you say.

Umm....no problem.

 

[blindsage]

There is always an opposite and equal reactive force...its one of the first laws of physics.

Yes, you're just applying the concept wrong.

So you always get recoil, the trick is to prevent the reactive force from acting on anything but the target...in other words, reflecting it back at the target through the miracle of postural stability.

You need to study your physics deeper, saying there is always and equal and opposite reaction is not necessarily the same as recoil. The only recoil you should have in the air is that of the air molecules, so not any perceptable. The 'recoil' you experience off a target is (which introduced and explained in an earlier post) when your force hits the object. Yes, posural stability plays a large part in what happens after that, but you can have 'postural stability' standing with your back against a wall and throwing a two handed strike, or putting your arms out straight and hittinga bag with your hips.

Imagine a gun held in a VERY strong vise...the force acting on the bullet would be much stronger because of the gun's rock solid immobility.

Or imagine the ground is the hammer of the gun and your body is the bullet. You'll get a lot more power.

 

[Telfer]

As to reflecting recoil, that should be taken care of by grounding yourself, not twisting around. By understanding the way the mechanics work, you will find that you are not having the force move you back.

Yes, thats what Ive said in more than one post...the book I referenced goes into more detail.

 

[Telfer]

Umm....no problem.

There is a critical problem actually...you may be able to generate a weak pushing action with a torso twist, but you will have minimal velocity. Its very slow.

A higher velocity is what you need to generate knock out power, and this only comes from contracting the tricep.

Stand in front of a heavy bag and this time dont twist your torso at all, but stand with a stable posture. Strike the bag only with your arm and you'll see that this is where your speed comes from.