# What is a sine wave?



## Gemini (May 6, 2006)

I've heard therm used from ITF practitioners, and I know it has to do with motion, but what type of motion? Where did it come from? For what purpose? Do any others arts use it?

I know, lots of questions. Any insite is appreciated though.


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## Rich Parsons (May 6, 2006)

Gemini said:
			
		

> I've heard therm used from ITF practitioners, and I know it has to do with motion, but what type of motion? Where did it come from? For what purpose? Do any others arts use it?
> 
> I know, lots of questions. Any insite is appreciated though.




A Sine Wave:

Draw a straight line across a piece of paper. 

Draw a half circle above the line. 

Where the right end of the upper ends against the line begin the next half circle where the left end of the circle underneath begins. This then continues to infinity. 

So would the question be circular or half circular techniques?


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## bustr (May 6, 2006)

It's just a graphic representation of amplitude, motion, flow rate or pressure over time. "Sine" specifically refers to a smooth arc on the graph. It sounds like the ITF guys are throwing out technical jargon to impress customers.

http://en.wikipedia.org/wiki/Sine_wave


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## shesulsa (May 6, 2006)

I'm not TKD, but this is the best I can answer that question:

The ITF uses a subtle sinewave influence in their movements in the idea that it provides more focused power behind strikes, hence allegedly causing more damage and offering more power.

Done correctly, it's rather inconscpicuous.


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## Rich Parsons (May 6, 2006)

shesulsa said:
			
		

> I'm not TKD, but this is the best I can answer that question:
> 
> The ITF uses a subtle sinewave influence in their movements in the idea that it provides more focused power behind strikes, hence allegedly causing more damage and offering more power.
> 
> Done correctly, it's rather inconscpicuous.



Could you explain a technique?


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## TigerWoman (May 6, 2006)

This is a topic that has been discussed numerous times.  If you do a search you would have found a lengthy thread on it but I'm sure you know that but here it is..  http://www.martialtalk.com/forum/showthread.php?t=1366&highlight=sine+wave  TW


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## shesulsa (May 6, 2006)

Rich Parsons said:
			
		

> Could you explain a technique?



Erm ... no, I really can't.  But when I went to GM Serriff's seminar in Clackamas (we were guests), he talked about sine wave and everyone else (a gymnasium full of people) around me was doing it.  I only mimmicked it.

I could describe what I did as a basic element, though.  Let's take a step-through punch, remembering that some Korean styles punch and step same-side, i.e. with a right punch, the right foot also steps through.   At the beginning of the element, there is the slightest lift, ebbing down (emulating the decline of the first part of sine wave) and half-way through the movement you are on a central plane, or x-plane if you will.  The second half of the movement there is a slight dip and return to the x-plane, emulating the second half of sine wave.

The theory can, I'm sure, be found at the link TW found.  My apologies for my bumbling explanation, I hope it was somewhat understandable.


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## shesulsa (May 6, 2006)

TigerWoman said:
			
		

> This is a topic that has been discussed numerous times.  If you do a search you would have found a lengthy thread on it but I'm sure you know that but here it is..  http://www.martialtalk.com/forum/showthread.php?t=1366&highlight=sine+wave  TW



I was really hoping someone IN the ITF would come forward and explain.  Thank you, though.


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## Marginal (May 6, 2006)

Bagatha is an ITF practitioner who responded on the subject in the thread TW linked. (I don't technically count myself since the USTF split off, but we do use it...)

From what I've read, Sine wave was initially borrowed from Chinese martial arts. (At least, the concept of downward motion adding to force led to its creation.) Unfortuantely, I can't source that anymore, and I've never read anything else that really explains the origins any deeper than "Gen Choi introduced it."

As I'm taught it now, the primary idea is to employ a natural motion. You don't keep exactly level when you walk, and when moving from one stance to the next, it remains more natural to slightly bend you knees before you move forward. The benefits are usually presented in contrast to a style like Shotokan which demands you keep your hips level through all transitions, which steals some power from the practitioner thanks to the startup motion being less biomechanically efficient. (Have to work a little more to get your rear leg moving forward.) 

Easiest explanation I guess would be if you're in a front/walking stance you'd bend your knees slightly before you start moving forward. While you're moving forward, you let yourself rise a little higher than starting position, and sink down as you set into stance. The motion's always described as down, up down. Sine wave's also used as a tool to help teach varying cadences in patterns. Connected - techniques done with no pause with a sine wave for each. Fast - techniques with their own sine waves but with a brief pause and performed faster than normal cadence, and Continous - techniques performed within one sine wave motion. (I might be off on those three. I haven't reviewed them in a while, and I didn't have much luck with my reference books.)

http://www.itf-information.com/patterns09.htm

Move #19 has an example of the cadence notation as it's used in a pattern.


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## Gemini (May 6, 2006)

Actually, both of those did help a bit. I wonder why Gen Choy adopted that and if it was in fact, a more efficient movement, the WTF style as I practice it, didn't follow suite. I'm hoping someone can come on that has practiced both methods and can speak to both accordingly. I appreciate your input.


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## Marginal (May 6, 2006)

IIRC, Gen Choi introduced it in the 80's so a lot of old timers remember pre and post sine wave methods of practice. It wasn't especially well understood whien it was introduced, (a strong initial school of thought beleived that the downward motion replaced hip motion which created a lot of confusion, and heel injuries etc) which further muddies the waters when the time comes to deliver the verdict.


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## Rich Parsons (May 6, 2006)

shesulsa said:
			
		

> Erm ... no, I really can't. But when I went to GM Serriff's seminar in Clackamas (we were guests), he talked about sine wave and everyone else (a gymnasium full of people) around me was doing it. I only mimmicked it.
> 
> I could describe what I did as a basic element, though. Let's take a step-through punch, remembering that some Korean styles punch and step same-side, i.e. with a right punch, the right foot also steps through. At the beginning of the element, there is the slightest lift, ebbing down (emulating the decline of the first part of sine wave) and half-way through the movement you are on a central plane, or x-plane if you will. The second half of the movement there is a slight dip and return to the x-plane, emulating the second half of sine wave.
> 
> The theory can, I'm sure, be found at the link TW found. My apologies for my bumbling explanation, I hope it was somewhat understandable.




Thank you!


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