How does Sine Wave look when done correctly, and how does it add power?

andyjeffries

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I know this has been discussed before, but I've got some specific references and I'd love an explanation from any ITF chaps/chappesses here....

As I understood Sine Wave (about a month ago), it was down-up-down and you land the strike on the final down portion of the movement. This always felt like although in theory you're adding gravity to the movement (which is a + in force) you're removing the solid connection and ground reaction force (so --- force). Boxers like Mike Tyson strike on the up portion of the movement, and I can understand that adds considerable power.

However, on another site I was in a discussion with someone and they said that you are 50% extended (let's say in to your straight punch) at the top of the motion, and that is when you impact the opponent. The remainder is follow through. This I could understand and agree it makes sense, it's literally impacting at the top of the "up" portion.

I followed up with some resources from General Choi (taking him to be the defining force or authoritative source for Sine Wave) and it seemed that my original understanding was correct.

Videos:
Book:
  • In Volume 2 (page 34) of his Encyclopaedia set. He shows that the hip is raised in the middle of the step and drops down from there in to the punch (and in the middle of the step where the body is at the highest, it can only go down from there)
Please take this as an "educate me - what is correct, and how does it add power", I'm open to understanding, if the answers are logical and reasonable. Thanks in advance
 
Your understanding matches how I was taught sine wave, but that was a minute ago. Does it add power? I don't think it does. The physics and physiology don't work. Although I practice the Chang Hon forms, I do them as I was originally taught - without sine wave. Since I haven't been with an ITF (or offshoot) school in decades, and the Chang Hon Tul are not required in our MDK system, there's nobody to squawk about it.
 
Power can be produced by delivering body mass behind the strike. It can be upward, using the bent legs to raise the body to a more upright position, it can be downward, dropping the body using "marriage of gravity", or it can be forward, using legs and hips. I think there is a time and place for each depending on circumstances, one's posture at the time, and desired target.

That said, from a non-TKD guy, IMO the sine wave seems excessive in motion and energy spent, and this may be counter-productive to power generation as well as speed. To me, short, direct, quick bursts of power are more effective. The exaggerated movement also telegraphs the step/technique. Perhaps it is an idea carried too far off the rails.

I'm not sure of the TKD theory behind it, but it seems to have drawbacks in practical applications.
 
Power can be produced by delivering body mass behind the strike. It can be upward, using the bent legs to raise the body to a more upright position, it can be downward, dropping the body using "marriage of gravity", or it can be forward, using legs and hips. I think there is a time and place for each depending on circumstances, one's posture at the time, and desired target.

That said, from a non-TKD guy, IMO the sine wave seems excessive in motion and energy spent, and this may be counter-productive to power generation as well as speed. To me, short, direct, quick bursts of power are more effective. The exaggerated movement also telegraphs the step/technique. Perhaps it is an idea carried too far off the rails.

I'm not sure of the TKD theory behind it, but it seems to have drawbacks in practical applications.
Since the movement is downward, I can see an argument for it adding power to downward strikes. But the idea of a linear art, such as Taekwondo, is that power is generated and delivered directly inline into the target. It doesn't seem to me that adding a vertical movement to a horizontal strike is going to do anything good or useful.
 
Boxers like Mike Tyson strike on the up portion of the movement, and I can understand that adds considerable power.

However, on another site I was in a discussion with someone and they said that you are 50% extended (let's say in to your straight punch) at the top of the motion, and that is when you impact the opponent. The remainder is follow through. This I could understand and agree it makes sense, it's literally impacting at the top of the "up" portion.
Explanation of "strike on the up portion."


marvin8 said:

Small guy...

1. Weight on front foot.
2. Shift weight to back foot (roll back/pull), while stepping ahead with front foot. This sets up mechanics for the right hand (push). Target (head) is between both feet.
3. Issue straight right by pushing off both feet, while shifting weight to front foot.

Unknown_ Sources
Nov 9, 2015

Never pick on the small guy

n1NKjUL.gif


 
To my eye, it looks as if he pushes up and settles down with the body, but allows the fist to stay level throughout.
(... and that he's exaggerating the up/down body motion)
 
I've always been fascinated with the sine wave too...

Is it possible that it's not so much the downward motion directly transferring energy forwards, but moreso a real 'sinking' feeling upon the forward strike allowing you to better root or connect with the ground? I could see that. So the power transfers more efficiently (without leaking out anywhere) as you get that 'connect' feeling with the ground straight upon impact?

And perhaps just super exaggerated in a larger way in forms to really connect with that feeling? Just thoughts, not a TKD guy but it's interesting to me.
 
I think this kind of goes in line with a video that @Tony Dismukes made a while back:


There are different ways of generating power. Some of that can be by pushing with your legs. Some of that can be with your legs lifting you to generate potential energy, which you use gravity to bring the power.

I've used gravity to generate power when doing power breaking with a downward hammerfist. It's also helpful in an axe kick or stomp. We see this in MMA with the superman punch and the ground-and-pound techniques. Or, if you want to look at grappling, I've used this with an omoplata sweep.

I have a slightly different interpretation of sine wave. Not the way it's taught, but the way I think of the principle. Since you can generate power with lift or with the fall, you can use the sine wave as it appears on a graph, with constant ups and downs. You can rotate left and right to generate power on subsequent jabs and crosses, so why not use level changes up and down to alternate power sources?
 

It's like a finger pointing away to the moon. Don't concentrate on the finger or you will miss all that heavenly glory.​

Bruce Lee
So, as an initial premise you can either accept that pattern motions are often exaggerated (Like Pulling the opposite hand to the hip, or length of stances) and have an esthetic quality - or not. So, my point is don't focus so much on the up and down motion of the body (Yes, there is a light initial down) but how it gets there which is primarily thru knee flexion. Also look at the bottom video and see how as part of the knee flexion the rear heal is raised and then lowered. Now with regard to the bottom vide comment "Don't twist your Bdy" my though is he was commenting on what he considered excessive shoulder / upper body rotation since he still taught using muscles of hips and abdomen to generate power. By flexing the knees you allow the utilization of the hips and abdomen more than if knees are not flexed. You can see Mike Tyson and other boxers flex their knees as they punch. These ideas are not unique to TK-D only the terminology is and it was a metaphor which General Choi used to contrast with Flat and Saw Tooth Wave,. Adddittionaly you hve the Kinetic Linking component . Compare what happens in this video with the bottom video above .
 
Explanation of "strike on the up portion."
Just to be clear, I don't know if this was for my benefit or for others, but I entirely agree striking on the up portion (although in Kukkiwon Taekwondo we tend to go "in" rather than "up") makes sense. It's the striking on the down portion that I disagree with, and knowing if that's even correct.
 
Take this with a grain of salt from a non-TKD guy.

When I first saw the "sine wave", I thought it was "WTF" TKD and I don't mean the World TaeKwonDo Federation...if you get my meaning.

I can't remember who because it was a lot of years ago, but I was talking with a higher ranking person in the ITF and we were discussing the "sine wave". He said that the majority of people do it wrong. Gen. Choi didn't have the best English, so in seminars he would really over exaggerate what he was doing to emphasize and illustrate what he was trying to say. According to this gentleman, the sine wave is supposed to be a lot more natural and not so artificial and much more subtle. Gen. Choi called what he saw most people doing, "see saw" and not sine wave. They are just going up and down in their movement without the other principles in play.

Some movements, the weight does "sink" to add more power, in other movements (as I probably poorly misunderstood it) it seemed that the "dropping" as you move forward was to almost get a "gravity assist" to get you there faster. To use a really poor analogy, think pedaling your bike on flat ground and then using the same effort to pedal on a slight downward slope. You increase your speed due to gravity helping.
 
>>>I can't remember who because it was a lot of years ago, but I was talking with a higher ranking person in the ITF and we were discussing the "sine wave". He said that the majority of people do it wrong. Gen. Choi didn't have the best English, so in seminars he would really over exaggerate what he was doing to emphasize and illustrate what he was trying to say. According to this gentleman, the sine wave is supposed to be a lot more natural and not so artificial and much more subtle. Gen. Choi called what he saw most people doing, "see saw" and not sine wave. They are just going up and down in their movement without the other principles in play.
FWIW my first in depth personal experience with General Choi was at an Instructor course in 1990. Prior to that although the term had been published in at least one earlier text. the term SW was not in widespread use. Although pre use of the term the texts did refer to bending the knees, Knee Spring and raising and lowering the hips. The earlier term we used was "Spring Style".

I agree that some recent examples excessively exaggerate the motion. The better examples are found on the internet in the videos which are filmed against a Black Background.
 
Explanation of "strike on the up portion."


marvin8 said:

Small guy...

1. Weight on front foot.
2. Shift weight to back foot (roll back/pull), while stepping ahead with front foot. This sets up mechanics for the right hand (push). Target (head) is between both feet.
3. Issue straight right by pushing off both feet, while shifting weight to front foot.

Unknown_ Sources
Nov 9, 2015

Never pick on the small guy

n1NKjUL.gif



Just to be clear, I don't know if this was for my benefit or for others, but I entirely agree striking on the up portion (although in Kukkiwon Taekwondo we tend to go "in" rather than "up") makes sense. It's the striking on the down portion that I disagree with, and knowing if that's even correct.
It was meant to be a benefit to the entire discussiongiving more detail on what you mentioned, "strike on the up portion." Your OP was so well balanced I found it interesting and didn't know exactly what side you were on.
 
Do a google scholar search and you can find several kinematics studies on power development in combat sport/martial arts. Most of them focus on Boxing and kick boxing but a few directly address the ITF sine wave. With the exception of one study that was administered by an ITF practitioner with clear biases and no control or baseline (it is a great study on how not to do a scientific study), the consensus is that to maximize power for a punch you need to have strong legs and core. The most beneficial exercises to maximize punching power is surprisingly squats and lunges and pushing against the ground and pivoting at the waist is the best way to deliver that power.
 
">>> the consensus is that to maximize power for a punch you need to have strong legs and core. "The most beneficial exercises to maximize punching power is surprisingly squats and lunges and pushing against the ground and pivoting at the waist is the best way to deliver that power.

I have read books on boxing stating that XXX% (A Large Percentage) of the punch power comes from the legs. It usually does not state how that percentage is determined. In order to use the legs to generate power in the punch you need to flex the knees. The resulting smooth raising and lowering of the body is what General Choi called SW in order to contrast it with "Flat Wave" (No raising / lowering) and Saw Tooth Wave (Sharp angular Raising and Lowering) The idea of flexing the knees is not unique to TK-D as a physical activity. Only the term is unique although like many things in patterns it may be exaggerated / stylized.
 
I have read books on boxing stating that XXX% (A Large Percentage) of the punch power comes from the legs. It usually does not state how that percentage is determined. In order to use the legs to generate power in the punch you need to flex the knees. The resulting smooth raising and lowering of the body is what General Choi called SW in order to contrast it with "Flat Wave" (No raising / lowering) and Saw Tooth Wave (Sharp angular Raising and Lowering) The idea of flexing the knees is not unique to TK-D as a physical activity. Only the term is unique although like many things in patterns it may be exaggerated / stylized.
I could be mistaken, but from the videos I've seen it also seems the ITF forms only utilize half of the sine wave. Where my interpretation of the principle is that it applies in both the lifting and falling.
 
I have read books on boxing stating that XXX% (A Large Percentage) of the punch power comes from the legs. It usually does not state how that percentage is determined. In order to use the legs to generate power in the punch you need to flex the knees. The resulting smooth raising and lowering of the body is what General Choi called SW in order to contrast it with "Flat Wave" (No raising / lowering) and Saw Tooth Wave (Sharp angular Raising and Lowering) The idea of flexing the knees is not unique to TK-D as a physical activity. Only the term is unique although like many things in patterns it may be exaggerated / stylized.
In the Taiji Classics they say: "The Jin should be rooted in the feet, generated from the legs, controlled by the waist, and manifested through the fingers"
 
I could be mistaken, but from the videos I've seen it also seems the ITF forms only utilize half of the sine wave. Where my interpretation of the principle is that it applies in both the lifting and falling.
I have never heard the principal mentioned in falling. I am having a hard time visualizing how that would work.
 
In the Taiji Classics they say: "The Jin should be rooted in the feet, generated from the legs, controlled by the waist, and manifested through the fingers"
And in my case all too often - blocked with the face.
 

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