Your Strokes:
Evan Chiang: Serve

Analyzed by John Yandell

Evan Chiang was already an accomplished player when he decided to come to San Francisco to work with me. He had been a ranked junior and played Division II college varsity tennis.

But his serve had always been his least effective stroke. Now, coming back to the game after a few years, he decided that he wanted that to change.

Working together with Evan, we made some structural changes in his motion that have also helped other players I’ve worked with. The first was widening his starting stance somewhat and offsetting the angle of his rear foot more on the model of Roger Federer.

The second was improving his racket drop by opening up his backswing and making it slightly more circular. The result was that the racket fell further along his right side, with the tip truly pointing down at the court. (To see how this worked for a touring pro, Click Here.)

These adjustments set the stage for the third change that I want to focus on here: improving his hand and arm rotation and controlling the role of the wrist.

The correct rotation of the hand and arm is critical in developing racket speed, velocity, and spin. But the issue is often confused by the heated debate on the role of the wrist, a debate that can verge into the fully irrational, if you follow it on the internet message boards.

Does the wrist actually "snap" during the swing? And how what role, if any, does that play in a great technical upward swing and in the followthrough?

The whole issue is further confused by the use of the teaching term "pronation." Technically in biomechanics, pronation refers only to the rotation of the forearm at the elbow joint.

However, the term is commonly applied to the way the entire arm and racket turn over on edge in the followthrough.

Studies by Brian Gordon have shown that pronation accurately defined as independent forearm rotation does not occur in high level serving. And you can see this clearly in our high speed footage as well.

The same is true of forward flex of the wrist. The wrist moves from a laid back position at the drop to a neutral position at contact and well into the followthrough. The wrist break, to the extent it even occurs, is a natural function of relaxation and deceleration at the very end of the swing.

So the key to a great isn’t the "snap" of the wrist. It isn’t the independent pronation of the forearm.

The key is the rotation of the upper arm in the shoulder joint. And research, as I have learned over the last few years, shows that this rotation is the major contributor to racket speed.

In biomechanics, technically this movement of the upper arm that is called "internal rotation." Basically it’s the forward rotation of the upper arm from the racket drop position. You can see it by watching the bicep, which goes from facing upward at the sky to facing downward at the court, a movement of roughly 180 degrees.

The internal or forward rotation of the upper arm starts as the racket starts upward. It then continues as elbow straightens out and through contact and into the followthrough. As the arm straightens out in the upward swing, this rotation also includes the rotation of the entire hitting arm structure and the racket.

This is the rotation that actually turns the racket face over on edge, causing the racket to reach the characteristic position of 90 degrees or perpendicular to the court surface that we see in high level serving.

Again, the forearm isn’t technically" pronating" or moving independently here. It is just along for the ride rotating with the rest of the hitting arm and racket structure.

But when we look at the video of Evan’s serve we can see that his internal rotation and therefore the rotation of the hitting arm and racket is quite limited. In the followthrough, at the moment when the racket face should be on edge, the face is actually pointing mostly downward at the court.

And also, notice there is a substantial forward wrist break. The two are related.

This reduction or breaking of the rotation is the effect I have seen time and time again when players try to "snap" the wrist forward under the mistaken impression that this is the key to power and spin. (Click Here for my early article on the Myth of the Wrist.)

In reality this forward wrist action is actually impeding the hand and arm rotation and inhibiting his ability to generate racket speed, ball velocity, and spin. So the question becomes, how best to make that change?

There are a number of drills I like to do to help players feel this critical rotational component in the service motion. The most basic is to simply model the motion from the racket drop to the fully rotated position in slow motion.

I ask players to do this as slowly as possible, and then to repeat this with the eyes closed focusing on the feeling and the visual image. Getting this image/feeling into the brain/body is key to actually making the physical change.

Although we know eventually the racket will fall and cross back to the left side, I ask players to stop the motion in this fully rotated position with the racket on edge, and use this position to create a mental blueprint.

Then as they actually serve, I ask them to make the racket pass through the model image. This process is tremendously powerful and can also be used to key the motion in actual play.

But there are two other non racket drills I like as well that help players feel the motion and have the advantage of eliminating the worry about whether they hit the serve in the box.

In the first drill the player simply stands on the baseline, puts the palm of his hand to his ear with the elbow pointing basically at the sideline. Notice the bicep is pointing upward at the sky.

Now, staying completely relaxed, the player rotates the upper arm forward as fast as possibly until the arm turns over 180 degrees with the bicep pointing downward at the court. The palm finishes on edge, perpendicular to the court surface.

I ask the player to just let the arm stay relaxed and do what it wants. The result is that it ends up in the perfectly aligned position you see in the serve of great players.

That’s the basic feeling of the hand and arm rotation in the swing. There is no forward break of the wrist past the neutral position. The alignment of the arm happens naturally and automatically as a result of the upper arm rotation.

In the second drill, the player starts from the same position, but this time with a tennis ball in his hand. In this drill the goal is to throw the ball upward, as high as possible, but have the ball still land in the service box.

This drill accurately simulates the actual upward motion of the serve from the racket drop. Note that it results in the same rotation of the hand and arm. Again the upper arm, forearm, and palm are in line, with the palm also on edge at about 90 degrees to the court surface.

The Process

So we looked at Evan’s serve closely frame by frame and saw the limitations. Then we did the various drills, including creating the physical and mental models.

Evan responded tremendously well. As you can see in the after video, he starts upward to the ball from a much better drop position. This resulted, as we noted, from opening up his wind up so the tip could point directly down at the court.

The key movement in the upper swing also changed dramatically. This was a huge difference and one that Evan immediately senses gave him the racket speed he was missing.

Watch the upper arm start to rotate on the upward swing. Watch the elbow straighten slightly before contact.

Then watch what happens next. The arm and racket continue to rotate as a unit well out into the followthrough. There is no independent forearm "pronation" or "wrist snap" just the unitary hitting arm and racket rotation.

Note how well his arm position now matches the model we created from studying Roger Federer. The arm and racket are roughly parallel to the court with the racket face on edge

Notice the wrist which is in a neutral position aligned with the arm and racket face instead of broken forward. This neutral position is key to generating power from the internal forward rotation of the upper arm. Again the forward break is what cuts that rotation off.

Evan noticed the difference instantly. The result was a noticeably increase in his velocity and also his ability to transfer his racket head speed into spin.

For the first time in his life he could actually feel a topspin component in his delivery. And this increased when applied the same motion to his second serve.

I’ll be working back and forth we Evan as he sends me video of his progress. I think the result is going to be very significant.

The amazing thing to me is still how well players at all levels respond to the visual input from the camera and the creation of a few simple model positions and drills!