POWER

Perhaps the most significant distinguishing aspect of our art is that we require powerful blows.  The method that I teach to create power has a strong theoretical basis.  That is the main thrust of this paper. 
Understanding this theoretical basis will allow you to make informed choices when choosing which technique to learn.  It will also help you in that learning by providing the understanding of why the technique is performed in a particular way.  

Teaching the “Snap”

This is the teaching analog for the Snap that I currently use. 
Start the training without using the sword, and help the student get the body mechanics down.  I suggest that you teach this with the students in a normal, shield-foot-forward stance.  (You can modify it later, if you wish.)  Also, insist on slow movements until the student can correctly repeat the motion.

1. Position the student in a proper stance.  (Please refer to my manual for a complete description.) The most important points are that it be upright, slightly "open" (feet not in line), balanced, with the sword arm held with the elbow back so that the muscle in front of the shoulder is tight, and the hand just below the ear, closed, with the palm down.
2. Stand on the sword side of the student, facing him/her.  Assuming a right-handed fighter, place the fingertips of your right hand on the second knuckles (from the ends of the fingers) of his/her sword hand.  Place your left hand lightly on his/her sword elbow.
3. Instruct the student to push lightly (stress lightly) into your right hand.  When you feel the pressure, tell him/her to maintain the pressure, while rolling the hand under yours.  Use your left hand to guide the elbow down and around the body, moving slightly across their chest.
4. When the elbow has moved about as far as it can, allow the hand to move directly forward in a line towards the target, as if the student is trying to deliver a back-fist strike to the face.  The hand should not move forward until the shoulder has fully rotated.

While this is happening, the student's weight should be moving towards their front knee (shield foot), while the shield shoulder pulls back.  While they are learning the technique, have them pull back and down with their shield hand, rather than holding (or pretending to hold) a shield.  This will help them to use their entire body to supply power.  Do not allow them to twist their back foot, or lean forward.  If you look from the side, the head should remain stable, with the sword hip moving forward, and the shield shoulder moving back.
There are several problems that might occur.

1. If the student continues to lean forward, have them execute the movement while your hand is right in front of their face, almost touching them.
2. Many students have difficulty moving their weight to the front foot during the technique.  Instead, they straighten or push back with the front leg.  Sometimes, I kneel down on their shield side, and pull the knee forward and very slightly to their shield side as they start the movement.  Alternatively, I will stand behind them, with my right hand behind the sword hip, ready to push, and my left hand on their shield shoulder, ready to pull.  As they start the motion, I push the sword hip forward, and pull the shield shoulder back.

If the student complains about discomfort of the left knee, either straighten that foot, or have them make smaller movements.  (The movements in slow training should be exaggerated.  They tighten up when executing the techniques at full speed.)

3. Make sure that their abdominal muscles are tight throughout the movement.  "Leading with the hip" is correct, but it is probably better to think about the whole body turning at once.  The hip will lead, but not by much.
4. Some students, usually the heavily muscled men, lead with their sword shoulder, bringing it “over the top”, rather than sliding under to follow the hip.  You can help them to correct this by pressing down on the sword shoulder, and holding it back during the initial part of the movement.  If this doesn’t work, use the technique of standing behind them, and pulling their left shoulder back and pushing their right hip forward as they swing, as described above.

Once they have the movement correct, let them use a sword, and eventually, let them speed up to full speed, in gradual steps.  If they are not using a pell, stress that the arm should not fully extend, to avoid injuring the elbow, and the blows should not be full speed.
Adding the shield is reasonably easy.  As the shield shoulder rotates back, the shield arm must extend slightly to keep the shield in position.  In any case, at full speed, all of the movements are tighter and smaller, so the arm is not required to extend a great distance.

Providing Power

Technical

The methods of supplying power to a sword swing that I believe are the most efficient are:

1. The rotation of the body of the fighter.
2. Moving the mass of the fighter slightly away from the direction the sword is pointing.

I prefer to use the analog of a rotating cylinder, when I discuss sword swings.  The body of the fighter would be the cylinder.  The rotation of that cylinder would be the first method by which the sword would be powered.  The other method would be the weight of the fighter’s body moving away from the sword – the weight adding to the pull of the rotating cylinder. 
From a standing start, my body doesn't move a whole lot - it's more of an almost simultaneous spasm of most of my muscles.  I increase power by leaning slightly away from the direction of the sword tip, specifically in the direction of the knee on my shield side, on a line about 30 degrees to the shield side of straight forward.
Please note that “leaning” in this context refers to a dynamic shifting of weight with an upright body, not leaning by bending at the waist.  I stress that it’s a dynamic lean – against the pull of the sword while it’s swinging, rather than static, leaning stance.
This isn't much of a lean, and probably wouldn't be noticed by an observer.  The front knee would probably not move more than an inch, at fast speed.  In this application, it isn’t even precisely a lean.  The body remains upright, and the weight slides slightly down, and towards the knee.
In the case of starting a sword swing from rest, the sword would fly to the target on a tangent to the cylinder.  It is much closer to a throw than a swing – actually more like the strike of a rigid whip - with the sword hand moving directly towards the target, and the sword tip moving through a curve to the same point.
When a mass (like a sword) is being moved from rest by a rotating power source (your body), it is easier to start moving if the radius of rotation is shorter.  The radius of rotation is the distance between the center of the rotation (the center of your body) and the center of the mass (the balance point of your sword) being moved.  For this reason, my stance with sword and shield is such that the balance point of my sword is held as close to the center of my body's rotation as possible - usually behind my head, resting on my shoulder.
An example of this is that it would be easier to start your sword moving, if it is resting on your shoulder, rather than being held out to your side with your fully extended arm.
Once the mass (sword) is moving, it hits harder with a longer radius of rotation.  For this reason, my swords balance about 7 inches in front of my hilt.  This is my optimum balance point for handling characteristics of the sword and the impact on contact.  This varies for the individual.
Contrast the hilt balanced sword with an axe.  The sword handles much better, and moves faster.  The axe hits a lot harder.
Using the Snap technique:

1. The power is applied in the earliest part of the swing is when the radius of rotation is the shortest, and the sword is easiest to move. 
2. This allows me to have the balance point of the sword moving as fast as possible when it whips around my body, extending the radius of rotation to produce more power at impact.
3. The sword then moves freely on a tangent (of the rotating cylinder) towards the target, with minimal or no power being applied.

Transmission Links

I believe that it is more efficient to use the large muscles in the legs and body to supply power to the sword blow, since they are the strongest muscles in the body.  These muscles apply power early in the sword swing.
I de-emphasize the use of the shoulder, arm, wrist and hand when applying power to the sword swing because they are relatively weak, compared to the muscles of the legs and body.  I am not saying that they don’t supply any power, but it is not efficient to rely on them to do so.
Since the muscles of the legs are separate from the body, the muscles of the abdomen must act as a power transmission link.  Once they are linked, they act as a unit.
Since the muscles in the body are not in contact with the sword, the intermediate joints – shoulder, elbow, wrist and fingers, must act as transmission links during the swing.
The transmission links work best if they are essentially rigidly connected.  If they are not, they must use their relatively weak muscles to transmit the power from the relatively stronger body muscles.  This does not provide an efficient transfer of force, since the weaker muscles in the transmission links can’t handle that much power – especially at the speed the power is being applied.
The tight abdominals are required to provide a power-transmission link between the lower and upper body.  The blows with swords have roughly the same mechanism as Karate blows, but the whipping effect created by the hip strongly leading the turn of the upper body doesn't work well in heavy weapons fighting, mainly because of the weight of the weapons.  It’s a timing issue.  The power application in a Judo throw is much closer, but more difficult to see as an example.

Not using Wrist and Arm

I acknowledge that the wrist, in some instances, can add power to a swing, but not the way I do it.

As I described above, the power for swinging the sword comes from a rotating pull from my center, pulling the sword towards its hilt, and from leaning away from the sword to shorten the radius of rotation.  Both of these factors require a center of rotation in my body.  This is obvious for the rotating pull, and the lean must have a properly oriented center of rotation to act upon. 

In both cases, using the wrist would tend to move the center of rotation towards, or to, my wrist.  Once this happens, it reduces the effectiveness of the application from the sources I've mentioned, since the powerful body and leg muscles wouldn’t have much influence on a center of rotation in the wrist, and it would not be oriented properly for the lean to be effective.

In addition, the wrist is the weakest link in the power-generation chain.  Following the old adage to "accentuate the positive", I've accentuated the more powerful power generators, at the expense of the weakest.  The elbow and shoulder would be the next in line for de-emphasis.  An over-reliance on the weaker power-generation links is what leads to wrist, elbow and shoulder injuries.

Concerning my fingers, I always keep a firm grip on the sword.  My lower fingers are tighter than are my upper ones, because I'm essentially pulling the sword to me.  I could, and have, taped my hand to my sword, and my wrist rigid, and had no problems fighting.  I didn't even have to make adjustments.  At no time do I tighten my fingers to apply power to the sword.

I want the sword to act as an extension of my arm, so I want the connection with the sword to be at the pommel end of the handle.  When this is the case, when the sword is deflected or rebounds, it acts as in integral part of my arm.  I don't want it to pivot around my hand, except at the very end of a strike, or in certain specific circumstances, like a wrap.

I do not use "triggers".  They make the connection to the sword at the upper part of the hand, and encourage it to pivot around the hand.  As a substitute, I sometimes use a lanyard that is attached to the sword in front of the hilt, and loops around my wrist at the base of my hand.  This holds the sword to my hand, but keeps the connection at the pommel end of the handle.

Injury

When talking about using the larger muscles and pulling the sword to increase the efficiency of the power application, there is another important aspect of this to discuss – injuries.
I feel that most of the injuries of the wrist, elbow and shoulder are caused by not swinging swords in the way I’ve described.  If the arm and wrist are being used as major sources of power in the sword swing, they are, in the vast majority of cases, being used in an application for which they are not suited.  To make matters worse, they are being used in biomechanically unsound positions. 
For instance:

1. If the sword hand is held forward, and the shoulder is not locked, the sword will be moved forward initially by a push from the body, rather than a rotation.  Since there is no rigid connection to the body, the sword must be whipped around by the forearm, both to add power and to properly orient the striking edge.
2. If, in an effort to strike a forehand blow over a shield, the arm is raised before the power is generated, the sword must be wrenched around by the wrist and forearm – both of which are in a terribly inefficient position.
3. The same is true, in reverse, when trying to throw a quick offside to the head.

Those of use who have arms like Popeye, and I’m one of them, can make all of these unsafe techniques work effectively.  At least, we can until the constant wear starts to injure our shoulders, elbows and wrists.  Luckily, I figured this out early, and avoided doing it, so I can still fight without elbow and shoulder pain, and I'm in my 60's, at the time of this writing.
A good rule of thumb when throwing a forehand blow is that if your hand is in front of your shoulder, and it is palm down, you are using too much forearm to throw the blow.  The further in front of your shoulder that your hand is before you turn it, the more incremental damage you are doing to your arm.  Blows thrown in this manner can be effective, but they will injure your arm.
I have various ways of deciding whether to teach a technique.  Probably the most important one is that a technique must not only be effective for me, but a 5’ tall, 110 pound woman must be able to strike with power, when using it.  So when you consider using a technique, ask yourself if it is useful to you only if you have sufficient strength.  If the answer is “yes”, then try to determine if that strength is being used to overcome unsound or injurious body mechanics.

Focus

Earlier, I mentioned that the Snap was less like a swing, and more like the strike of a rigid whip.  Carrying this simile further, the strike of the sword is directed towards a point.  This creates an impact at that point.  If the point moves because of the strike, the movement is caused by the energy transferred during the impact of the sword, rather than by the sword pushing it.
In the case of the Snap technique, which is designed to create an impact at the point of contact,

1. The energy of the sword is released all at once, in a very short time. 
2. When the sword comes in contact with the target, all of the energy of the strike has already been supplied to the sword.
3. The fighter is swinging to the target.
4. If performed correctly, the sword will not be moving after initial contact at the target.
5. The technique is designed to break what it hits.

In the case of a swinging blow, which is driven to a point past the point of contact,

1. The power is released in a longer period of time. 
2. It is very likely that energy is still being applied to the sword. 
3. The fighter is swinging through the target”. 
4. If performed correctly, the sword will be moving after the initial contact.
5. The technique is designed to move what it hits.

One of the demonstrations that I do to illustrate this, is to swing at a target that is out of range.  Of course, I can’t reach the target, so I am aiming to a point that contains nothing.  Using a full speed swing, the sword stops at about that point, and rebounds due to the “spring” of my arm. 
I have found that this demonstration is not a good thing to do very often, since because it strongly pulls the tendons in the back of my hand have.  I’ve since modified the demonstration by releasing the blade, which then flies directly forward, spinning as it goes.

*  *  *

I feel as if I should explain, “designed to break what it hits”. 
Many relatively solid materials are elastic.  This means that if an object made of this material is deformed, it will return to its original form.  Some materials return much quicker than others, and those are considered more elastic.  Steel, for instance, is very elastic – much more so than rubber.  It just takes a lot more force to deform it.
The speed at which a material returns to its original form determines its coefficient of elasticity.  If a material is deformed at a speed that is greater than its coefficient of elasticity, it will not return to its original form.  It dents or breaks.
The Snap delivers all of it’s force in a very short time, which produces much higher acceleration of the target than would a swinging blow of the same force – since the force of the swinging blow is delivered over a longer period of time.
The Snap is designed to break armor.  This is not to say that armor cannot be broken with a swinging blow.  You just have to hit harder.
There are several advantages to the Snap:

1. They are easier to control.  The force is transferred more efficiently at impact, and therefore does not require as great a force to be applied to the sword as the swing starts.  Since less force is applied, it is easier to control.
2. They are safer, in some cases.  They are designed to break the armor, not the fighter.  The force is applied to the armor.  The armor, since we are using rattan, absorbs it, even if it dents.  If it misses the armor, it stops, rather than being driven in.  The concussion will leave a nice bruise, in any case.  A blow with significant follow-through will continue in its path, with force continuing to be applied.
3. They hit harder with less effort, again due to the efficiency of force transfer.  This makes it easier for weaker fighters to strike powerful blows.

If the aggressor is very powerful, the swinging type of blow can more easily lead to injuries because of the more severe movement it causes in the target, and the greater amount of force used, in general.

1. They do not pull you out of position, if you miss.
2. They allow you to retrieve your blade quicker.  Since your body does not continue to push or rotate forward after the blow strikes, it can move into the return motion sooner.

Returns and Combinations
If the sword is already moving, as it would be when it is moving through a return of the sword from one blow while it is moving into the next blow of a combination, the same factors for generating power, rotation and leaning, still apply.  The main differences are:

1. The sword is already moving, and has momentum.
2. The radius of rotation is greater than if the sword was starting from rest, on the fighter’s shoulder.

The rotation of the body continues to pull the sword around a curve, since the mass of the sword is held by a rigid tether – the arm. 
Since the starting radius of the rotation of the sword is relatively great, it provides another opportunity for applying power to the blade – reducing the radius of rotation.  The lean of the body away from the sword serves to reduce the radius of the curve, so the speed of the sword will increase.  I must stress that this lean is very small, in most cases.   
This is one instance where the arm can be used effectively and efficiently in the process of generating power.  When the sword is swinging around in back of the fighter, simply flexing the arm pulls the sword in towards the fighter’s body by pulling it towards the sword’s hilt, down the length of the blade.  In this way, you decrease the radius of rotation without fighting against the rotational momentum of the blade.
This has some implications concerning technique. 

1. Since reducing the radius multiplies the speed and power of the blade, the resultant speed and force will be much greater if the sword already had a lot of speed and power.  Therefore, most of the force should be applied to the blade on the backswing.
2. Any continuous backswing must follow a smooth curve as it comes back forward towards the target. 
1. If it does not, most or all of the rotational momentum, and therefore power, will be lost. 
2. Using the concept of pulling the sword around curves, hilt first, also provides a method of changing the direction of a forehand blow significantly.

Since many fighters do not create this curve in their backswings, they are forced to use a lot of arm to supply power for the subsequent swing – especially those to the offside.

1. The technique must be constructed such that the “lean” of the body occurs during most of the swing, starting from its beginning.  This enhances the torque being applied by the rotating body.  However, the reduction in the radius of rotation caused by flexing the arm must occur later in the swing, so significant rotational momentum exists to be multiplied.

For example, consider throwing an overhead offside blow as the second blow of a combination – the first blow of which was a forehand blow.  You often see a fighter lean strongly towards his/her shield side immediately, at the start of the backswing, then pull the blade forward and swing with his/her arm to complete the blow.
What is happening is that the complete lean has occurred so early in the backswing that it is perpendicular to the direction of the blade, which is still pointed at (or perhaps still touching) the target of the first blow.  Since little or no rotational momentum has been generated, and the lean is in the wrong direction (it is not pulling the hilt of the sword down the blade), it does nothing to increase power.  In fact, since the lean has already occurred, it can no longer be used in power generation.  Additionally, it inhibits further rotation, taking most of that power source out of the equation.
This is not to say that you should never throw a blow to or from the offside once the sword has stopped.  If you do, though, you should be in a position so that your arm is already cocked, and your body can easily rotate back to supply power. 
Please note that this can work well in the middle of combinations, but effective, powerful blows in this situation require a lot of movement to set up.  If you are doing one with the blade at rest in normal starting position, and not in the middle of a combination, you will be giving your opponent a lot of warning.
However, if the backswing technique is such that the sword does stop at the rearmost point, it is most efficient to start the swing forward by pulling the sword towards it’s hilt, rather than trying to move it sideways.  This is essentially the same technique used in starting a swing with the sword at rest. 
For instance, if you've done an overhead return:

1. Your sword is roughly horizontal, just over your head, about 6" towards your sword side, pointing towards your opponent.
2. Your sword arm is behind you.  The upper part of your sword arm is horizontal, with the elbow pointing towards the rear, with the forearm vertical

If you simply move your hand forward, even if impelled by the rotation of your body, the sword will simply change ends, without swinging, unless you twist it around with your forearm.  This isn't good for your elbow.
If instead, you pull back slightly on the hilt, as your body starts to rotate forward, or if you simple "kick" the tip of your sword back with your thumb, the blade will follow the hilt around the small circle mentioned above, accelerate nicely, and provide a good impact.

Wraps
In this case, I am referring to the “big” wraps, not those techniques that are essentially a regular forehand blow, during which the hand turns over (snap-wrap).
The power for wraps is generated by reducing the radius of rotation of the sword by changing the position of the center of rotation.
When the sword is swinging at the end of an arm, and that arm stops, the blade will pivot around the hand at the end of the arm (the turning point).  When this happens:

1. The center of rotation moves from the center of your rotating body to your hand.
2. The radius of rotation is reduced:
1. From the distance from the center of your body to the balance point of the sword (which is being held at the end of your partially-extended arm)
2. To the distance from your hand to the balance point of the sword.
3. The result is that the sword speeds up a lot, when the radius of rotation is drastically decreased as the sword “goes around the corner”.

Unless you have very fast foot speed, just stepping into the wrap will take too much time, and give your opponent too much warning.  I prefer to use another technique to close the distance, and use the wrap as the second blow.  I usually use an offside blow as the lead-in technique.  This blow does not have to be powerful, just quick, to cover the slide step with your shield foot being used to close the distance.  This could just as well have been a right cross (snap towards the opposite shoulder).
I used the offside for the example, because performing an overhead return puts your arm is a perfect position to do a wrap, as you start to step into the wrap with your sword foot. 

To throw the wrap:

Perform the lead-in technique, then:

1. Start the step with your sword foot as you do the overhead return.
1. The step with your sword foot should be towards the turning point (where the sword will swing around your hand).
2. The distance between the turning point and the target should be the distance between your hilt and the “sweet spot” of your sword.
2. As you take the step into the wrapping position with your sword foot:
1. Delay shifting your weight
2. Have your sword shoulder and hip lag behind.  When you do this while stepping forward, you are “winding” your torso like a spring.
3. Simultaneously, shift your weight towards your sword foot, and twist your sword hip and shoulder forward – both towards the turning point.
1. Lean slightly to your sword side, so that the sword hand moves forward in a shallow curve, rather than a straight line.  Don’t pull your arm in towards your shoulder.
2. As you do this, don’t unlock your shoulder, or extend your arm, but move the sword elbow slightly in, as your body turns.
3. Allow the blade to swing around towards the turning point – like a slightly curving snap with the arm partially extended.
4. You can your arm to extend – not fully – as the blade approaches the turning point.
4. Since you are moving everything in a circular motion from sword-side towards shield-side, while shifting your weight towards the turning point, the motion of your hand is easily stopped, without pulling back, because it is moving in a curved path, and stops sideways, rather than along the length of the arm.
5. As the blade swings around the turning point, push towards the turning point with the heel of your hand to keep your hand from moving in towards your opponent.

Notes:

1. The plane in which the wrap occurs is basically defined by the line through your shoulders.  To throw a low wrap, lean towards your sword side as you throw.  To throw a high wrap, lean towards your shield side as you throw.
2. The arm never fully extends.
3. The arm remains “locked” at the shoulder.
4. Everything should arrive at the turning point at the same time - your weight, your shoulder, and the sword.
5. It is important to deliver the blow so that the impact is close to the focal point of the swing, which is when the blade is roughly at a right angle to the original direction of the swing.

Problems

Potentially injurious problems arise when we consider how the hand is stopped. 

1. If the arm fully extends

If the arm is fully extended, and the hand is stopped because of this, considerable stress, in the form of a sharp outward pull, is placed on the elbow and shoulder.

1. If the arm is pulled back sharply

The same thing happens when the hand is stopped by the sword hip and shoulder being pulled sharply back, causing the arm to fully extend.

1. If the elbow rises above the plane of the shoulders

In addition, for the higher wraps, the elbow is often above the plane of the shoulders, and this causes the shoulder to be “unlocked” when the stress is applied, so that the shoulder is not in an optimal position to withstand the stress.
Please note that very powerful, fast wraps can be thrown while doing all of these things.  However, the shoulder and elbow will suffer incremental injury, eventually to the point of disability. 
The technique cannot be used for wraps thrown with your sword hand close to the front of your face.  These require pulling back with the sword hip, shoulder and elbow.  While these techniques are effective, it is my opinion that the poor body mechanics involved will eventually cause injury to the person using them.
To avoid this problem:

1. Never extend your arm fully when using these techniques.
2. Don’t pull back sharply with your shoulder or hip, especially if it fully extends your arm.
3. Keep the elbow below the plane of your shoulders to keep the shoulder “locked”, even if it is necessary to tilt the plane of the shoulders to make this happen.
4. Use the rotation of your body (shoulder), rather than your arm, to move the sword.  Try to throw the wrap without unlocking your shoulder.  You may not be able to do this, but the closer you come, the better off you will be.
5. Shift your weight (an upright lean) towards the turning point of the sword around the hand, not towards the target.  For best results, time it with the blade arriving at the turning point.
6. Keep your hand from moving in towards your target from the turning point of the blade.
1. This not only reduces the force of the blow by increasing the radius of rotation, it causes stress on your elbow and shoulder because you are applying lateral force with an extended arm.
2. To help keep your hand at the turning point, push forward with the heel of your hand as the blade crosses in front of your hand.

And never throw a wrap which consists of simply a swing with the back edge forwards.

Post Script
I am very much in favor of retaining a reasonably high level of force (calibration) in our fighting.  Powerful blows require good technique.  If powerful blows are no longer required, then proper technique will no longer be required.  When this occurs, some fighters will start using techniques that are faster or easier to perform, but which could not ever supply decent power.  This degrades the art.
Of course, this is my opinion.