I should add that I think your son has already got the complicated part of a good twist serve figured out, as his upper body is almost textbook. Now he just has to start tossing the ball further into the court, lean the left hip out in front of his legs as he crouches to get the body weight in front of his base, then launch forward and upward into the ball. Once he finds the right slot for his toss location to do that, his serve will be a monster.
Beware of this. Your son is young ang flexible and he actually bends his back a lot, but that is neither required nor good for future health. The goal is to get altered swingpath due to torso/shoulder orientation, which is healthily achieved by spine/torso tilt and rotation away from the target. "Limbo" position by pushing hip forward, bending knees, getting on toes. Back arc barely gives an advantage and puts that poor back under huge stress.
Well that's expected to be a reputable source. Still I don't see best pros going with such pronounced back arc, even when serving evidently twisting serves. And multiple sources warned against overdoing back arc. It's up to you to continue observing examples and decide where to move.
Well that's expected to be a reputable source. Still I don't see best pros going with such pronounced back arc, even when serving evidently twisting serves. And multiple sources warned against overdoing back arc. It's up to you to continue observing examples and decide where to move.
Add: I'm also not found of his "buttscratch" demonstration - he seems to overbend the elbow, and dropping the racquet head deeper, to the butt, is still not the "scratching the back of a nearby person" which is observed for better mechanics. So taking this into account, author is at least not 100% credible, which makes me further question his ideas
I think it's really quite good. For me I always start from the toss. In this case I would say the toss is too far behind his head personally. That's one thing that arching the back will do is allow a farther behind toss, but I don't like it so far back because it encourages the bending of the back more than might be necessary and it's also a real giveaway for a lot of servers. That type of toss almost always means the spin out wide. It will give a good returner plenty of time to camp out for the return.
The other thing I think I notice is that the rotation of the arm is not happening during contact. It looks to me, as best I can tell from that video, that he is using quite a bit of wrist deviation when brushing the strings across the ball. That works up to a point, but in my experience it will limit the max swing speed more so than developing a nice rotational technique during the contact. I've struggled off and on with that myself over the years because I learned it first as the most obvious way to brush across the ball. I still fall back into that at times if I'm not careful. Usually just a basket of balls with some slow and deliberate kick serve practice will straighten it back out. You can swing more aggressively and disguise the direction better with the rotation of the arm during the contact. I think it also gives a little more power as you are rotating into the ball a bit as you brush across it.
I like to call that motion of the hand and arm right at contact the "swingularity". Been using the phrase with my students for a long time now. Next to a perfect toss, the swingularity is the second most important component to an awesome serve in my opinion. That motion was the magic component to the serve that I was never taught and had to learn for myself from reading articles and trying to do the different drills I found in them. I wish that I would have been taught it from the beginning, but I still see coaches all the time having their students drill serves with forehand grips. Drives me nuts. Looks like you are doing quite a good job with your son, so kudos to you.
The serve above is what most people think of as a ‘topspin’ serve, but the spin axis is actually roughly 60 degrees from horizontal (or 8 to 2 clock angle). A spin axis 10 more degrees toward horizontal (50 degrees from horizontal, or 7:10 to 1:40, as documented in Cross’s article) will produce a twist serve ‘kick’ to right from server’s vantage point, keeping everything else the same. Conversely, adjust spin axis the other direction, toward 8:30 to 2:30 click angle, will produce a bounce in the opposite direction “topspin slice”).I have video information on the kick serve but none on the 'twist' serve.
I see the racket rising in the three frames before, during and after impact.
Your receiver's view camera arrangement can show the bounce to the side for the kick serve. For the receiver, the bounce appears to the left and for the server, the bounce appears to the right. The direction of the bounce shows up best if the camera is aligned with the trajectory at the bounce.
Here is impact and the trajectory. The camera is hand held and was moving around during the video clip.
The bounce or closest to the bounce. Because of the moving camera, the location of the ball's trajectory to the court is most accurate in this one picture.
Rising ball.
I believe that the ball might have appeared like this and still might have had a little bounce to the left, but I think it had no left bounce. Repeat, camera looking along the trajectory at bounce to improve accuracy for seeing any bounce to the side. Camera behind server looking along the trajectory will show direction of bounce also. With wide angle lens on a smart phone - ?
The leftward bounce comes about because of the large tilt on the spin axis. See post #11. Buy reference Technical Tennis and look at the location of the racket on the ball. Take a racket and ball and see the tilt on the racket to first contact the top half of the ball.
I believe the serve above is a top spin serve and that the racket was not closed at impact using that technique. The racket was probably neutral - not closed - at impact. The racket was not tilted forward/closed as for a kick serve at impact.
I have posted on the kick serve and tilt many times.
https://tt.tennis-warehouse.com/ind...jectory-off-the-racquet.619786/#post-12416289
Do you ever see the ball bounce to the side - to right for the server or to left for the receiver?
Thanks for illustrating that; I do however want to clarify that the video I posted from the receiver standpoint is merely a topspin serve the first video from the server standpoint is the twist ! It Does illustrate the racket continuing upward after impact .
I return his serve all the time and sometimes it’s topspin and sometimes it’s twist depending on how much racket tilt forward he gets . He gets discouraged because sometimes if he tries to get more forward tilt he hits it in the net.
Chas is over-complicating it. Your son is doing just fine finding the right swingpath to make the ball twist. Just work on making tweaks that assist with generating more racquethead speed relative to the ball (more forward leg thrust, deeper racquet drop etc) , and his serve will take off and get better and better.
I am having a problem with interpreting this picture. The red bounce could be going to the side and I believe that it is. But is there some way that the picture can fool us? This is the 2D image of 3D space problem that cameras have.
I think that if you view from behind the server trying to get parallel to the ball's trajectory approaching the bounce, that might be the best view to see the side bounce. Forget the ball's drop and align the camera to the azimuth angle.
It looks like an excellent serve.
The quick interpretation.
I return his serve all the time and sometimes it’s topspin and sometimes it’s twist depending on how much racket tilt forward he gets . He gets discouraged because sometimes if he tries to get more forward tilt he hits it in the net.
I must step forward to support fellow @Chas Tennis here: there evidently is a “drag effect” of the strings when hitting the ball with angled stringbed. This effect lifts the ball on topspin groundies with vertical/closed racquet face (you can find numerous videos when descending ball is hit in the same manner); this effects allows to hit backspin volleys downward with vertical/slightly open racquet face. And same effect allows serving with tilted (closed) racquet face rising through contact to result in ~horizontal initial ball path.
You can only do this with racquet face open a few degrees, right? Also I’m not talking lob type. Just any shot where ball hit at, e.g., belly level and passes the net several feet higher.
