Spin Servers—Do you snap your wrist, curveball style, on the serve?

[SouthernCourts]

I just realized last night that when I try a spin serve (it's a new one for me, trying to save my back some stress by getting away from the second serve kick), I snap my wrist using basically the same motion I used to use when throwing a curveball in baseball. I also realized that this might not be necessary, and it's causing a few twinges in the arm. Curious if this is normal, or if the proper technique is just to let the motion and angle of the racket impart the spin. Thanks for any help.

 

[SinjinCooper]

Do not do that.

 

[fuzz nation]

Let the motion and angle of the racquet impart the spin.

Trying to make spin by actively scooping the racquet around the side of the ball when you serve will only put lots of extra stress on the connective tissues in your wrist and forearm. The movement of your wrist can't actually turn the racquet at contact to then turn the ball.

If you're after a good sidespin/slice serve, you can experiment with very simple alterations to your flat serve. The idea is to get more of the angular contact with the ball that's necessary to make spin. Use the same full move through the ball that you use for your natural "flat" serves. To get that sidespin, just shade your grip position slightly more toward eastern backhand - maybe not even a full bevel - and aim your serve a few feet more to the right (if you're a right-hander).

You need racquet speed to generate spin, so use your natural full release and let the ball come off your angled racquet face with the spin you want. After some experiments, you'll gain a sense of where this "crooked" serve will go and your control will improve. It may also feel like you can hit this serve better with your toss located slightly more to the right (again, if you're serving right-handed).

 

[weelie]

I like the "skipping rocks" analogy for slice serve. Works for me.

 

[Chas Tennis]

Here is a kick serve. You should look for similar videos. Your technique and wrist movement can't be described with words. People have been arguing over what a 'wrist snap' is for a long time. If you want to study this issue find videos and take videos of your own technique. This issue requires high speed videos such as 240 fps with small motion blur.

Video showing internal shoulder rotation leading to impact for the kick serve. 240 fps video, 4.2 milliseconds between frames.

To examine single frame - Click "Vimeo", Click full screen. Hold down the SHIFT KEY and use the ARROW KEYS.

Close up of arm with wrist watch. The ISR at the elbow is shown by shadows and bone features. The racket is fixed to the hand and gives an indication of the wrist rotation. The wrist watch can be used as a marker to indicate the rotation of the wrist. The negative millisecond scale gives the time before impact. The positive scale gives time after impact. The highest edge of the racket is shown by orange lines before, during (squished ball),and after impact. Also, the highest edge of the frame for the top of the racket path is indicated by an orange line.The ball's trajectory is indicated by red crosses.

Internal shoulder rotation of the upper arm at the shoulder joint is indicated directly by the rotation of bones at the elbow. When the elbow is near straight the total rotation seen at the wrist is the sum of ISR and pronation. Not serving I can get a total range of motion at the wrist of about 270 d by using ISR and pronation. Try it. For the serve, it appears that the total rotation, start to impact, is under 90 d, 70 d.? Mostly ISR accelerates the arm and racket.

If anyone has a video showing another racket motion to get a high level kick serve, please post.

The bounce to the right is an impression from the high speed video and not measured so the serve could have been a Top Spin serve instead of a Kick serve.

This is how the racket moves for a high level kick serve. Toly produced gif with composite frames.

The frames are 4.2 milliseconds apart for 240 fps video.

Racket position #1 - before impact. Racket lower.
Racket position #2 - during impact (all racket effects on the ball occur within about 3-5 milliseconds around this time).
Racket position #3 - after impact. Racket higher and around the highest point that the racket reaches.

Total time shown in 3-frame gif above, 8.4 milliseconds.

A 30 fps video captures one frame every 33 milliseconds, so that 30 fps cannot possibly show this detail.

The above is why high speed video is required to examine the faster parts of the serve.