Close-up video of different Wrist-actions

http://www.badmintoncentral.com/forums/showpost.php?p=972222&postcount=50
watch the video with lee H jung smashing in slow motion

 

Yeah, #3 (pronation and supination) is where wrist power comes from. If you look at #1 (radial and ulnar deviation), it controls the balance between reach and torque when you have a racquet in your hand. #2 (flexion and extension) is not a critical movement in badminton.

I think the current nomenclature for these movements is fine, throwing in terms like hand-action or forearm movement will just serve to confuse people even more. Think of it this way, for pronation/supination you rotate the wrist relative to your elbow, not the other way around which is potentially implied if you call it forearm rotation. Therefore, wrist rotation is a better term for describing the movement.

 

Using the technical terms is great when you're discussing something through writing, but from an instructor's point of view it is best to keep it as simple as possible. Most people are not familiar with the term pronation and supination, and most of those that do usually are not so familiar with it that they can effortlessly visualize the movement just from hearing the term.

 

1 is mainly used for front bachkand shots but it must be executed with a snap to get velocity. 2 is wronly demonstrated and will only hurt your wrist but will send the shuttle nowhere. 3 is only used for forehand shots hit around the head due to its horizontal orientation. Adjust 3 to hit overhead shots like clears, drops, and smashes and you have it.

 

All these movements are used in badminton, although to varying degrees and depending on the shot.

Of the three, only (1) and (2) are wrist movements. (3) is an arm movement (and yes, Mikael has the correct anatomical terms for them).

 

Extension followed by moderate flexion is useful for many forehand shots. For example: for forehand net lifts, a key coaching point is to hyperextend the wrist ("cock it back"). However, the following flexion should not go as far: only back to neutral, or a little farther.

Correct, although there will also be some wrist movement.

Er, what? Not sure I understand this.

Reaching your arm up in the air is used to reach high! Your wrist has little to do with it.

Some radial deviation typically accompanies extension in the backswing, followed by flexion and ulnar deviation in the forwards swing (both limited).

I wouldn't recommend that; change your swing direction and timing instead. You can use grip changes to create sliced smashes, but they don't work well for full-power smashes (you'll end up slicing the shuttle and losing power).

You can also create sliced smashes simply by changing your timing (hitting when your arm is more or less pronated). This is the method I would recommend.

(See my "Which grip for clears, smashes, and drops?" page.)

*sigh* Is it so difficult to maintain a balanced view?

Some people say, "Badminton power is all in the wrist. Only beginners use arm power."

Other people say, "Badminton power is all in the forearm. Using the wrist is a myth."

I say: "Badminton power is mainly in arm rotation, but powerful badminton shots also involve wrist movements -- often on both axes. Often the forwards wrist movement (flexion or ulnar deviation) is less pronounced than the backwards wrist movment (extension or radial deviation)."

I agree that the role of wrist flexion is limited in badminton. Certainly we should not over-emphasise flexion and encourage panhandling! But neither should we say, "wrist flexion should never be used."

 

Is that correct?

If you keep your wrist in its neutral position, and stretch your arm vertically while holding a racket, the racket will be at around 60 degrees to the axis of the forearm. You can get the head much higher by using #1 movement, but not otherwise.

 

You should avoid hitting at full stretch. There should be at least slight angles at each joint.

For arm rotation to be effective, you need some angle between the racket and the forearm. That's how you generate power from rotation. If the racket remained perfectly in line with the arm, then your shots would have hardly any power.

Hitting at full stretch also increases your risk of injury.

Think of hitting at full relaxed reach.

 

Ulnar and radial deviation control the balance between torque and reach between the forearm and the racquet. At full ulnar deviation you have a 90 degree angle at the wrist which maximizes the torque on the racquet. This is key in the early part of the stroke when energy is being transferred from forearm rotation into the racquet. As contact is about to be made and racquet head velocity is already high, there is a tendency towards radial deviation to increase the vertical reach for the shot. However, there can't be too much because at impact you have to stiffen momentarily to transfer energy out to the shuttle. At full radial deviation the impact load is taken by the wrist flexors (in the case of a forehand stroke) which is too weaker in that position and so a poor shot results.

 

You got these the wrong way around (probably a typo).

At full radial deviation you have a 90 degree angle at the wrist, which maximises torque; at full ulnar deviation you have maximum reach.

Apart from that slip, a top-notch explanation that I fully agree with.

By the way, for anyone who has trouble remembering which is which: your radial pulse is located at your wrist underneath your thumb (find it with two fingers). Radial deviation is movement towards this; ulnar deviation is movement away from it. That's how I remember it, anyway.

 

Whoops, I always get those two bones mixed up. Good call Gollum!

 

So is it preferred to use pronation and suplination in every forehand shot like drops, clears, smashes etc.?

 

It's mainly important for power shots, such as clears and smashes.

When playing softer shots, such as drops, there may also be some arm rotation -- but it will be much less violent. Some drops will use more than others (a cross-court reverse slice drop uses quite a bit of arm rotation, for example).