The server does hit upwards on most second serves
Hitting Up on Serves
- Thread starter Topspin Shot
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The server does hit upwards on most second serves
It does make sense in a general way. But here we are really nit-picking. That is where the fun is. Otherwise we could all just agree with whatever Vic Braden said about this (or Djokovic about wrist snap for that matter) and go home.
BTW, Vic Braden has been challenged on a number of other topics on this forum in the past.
donquijote
G.O.A.T.
How can it hit upwards when body has moved forward and has a vertical angle? But oh I know what you mean and you are right about the second topspin serves. But the discussion here is not about those kind of serves and not illustrated in Tomas' video and script.
That is what I have been saying for years
Raul_SJ
G.O.A.T.
Braden was very scientific -- using high speed photography and experimentation. Not familiar with the details on how Vic Braden proved that all serves are hit up, but he would not make the claim without strong evidence. And I have not heard anyone challenge Braden on the claim of all serves being hit up.
donquijote
G.O.A.T.
There is no way that Raonic hitting upwards with that racquet head speed (>100 mph) and it is landing in the serve square on the other side. It has to have an angle downwards.
There are two things which can bring it down if even it is hit up (as in second serve): gravity and top spin. My point has always been that in cases like the above, neither is powerful enough to bring the ball down into the box if Raonic had really been swinging up (which is what you are saying).
That is because most people would understand that he meant swinging up and not what happens at a very fine resolution. From the context, no one would argue with him. I have taken a 1 day clinic with him and he said hit up on the ball because a lot of beginners serve by using a downward motion, like an overhead smash.
donquijote
G.O.A.T.
Of course he is swinging up like anybody else. Even a beginner is swinging their racquet up. But when the racquet meets the ball, there is an angle created by all contributors. His contact point is way high compared to recreational players and until then he is making more distance to create more head speed as Tomas mentioned.
ARKustom93
Professional
Yes, there is ... And that downward angle happens, because vertical RH speed near hand apex(full arm extension) converts into horizontal speed.
In simple terms, the upward arm extension brings up the racquet hand, which at full arm extension can't go up any further, so the vertical RH momentum generated by that up-swing, by means of the racquet's long axis rotating/pivoting about the wrist, turns into horizontal head speed, naturally creating the desired downward angle into the service box. In or out?? Question of timing, nothing else.
Raul_SJ
G.O.A.T.
Braden was not just offering the general advice to swing upwards. He was also addressing the specific issue of racket angle at the contact zone.
Players should keep their head and chest up throughout the critical contact zone. If a server’s head pulls down early, this can dramatically change the racket face angle, which in turn can severely alter the placement of the serve.
Tennis researchers have uncovered some interesting data:
70 percent of a serve’s ball speed is produced by the internal rotation and hand speed of the arm. To have a monstrous serve, a player should focus on these elements.
Sometimes, though, in an effort to accentuate forearm pronation, players mistakenly try to hit down on the hall. After all, this feels natural; almost all players are contacting their serves from well above the net.
However, in the early 1980s at the Vic Braden Tennis College, we did an interesting serve study. One of our students was Artis Gilmore, the 7-foot~2 former star center for the Chicago Bulls. Even at his extreme height, Artis was still too short to hit down on his serve.
Tennis researchers have uncovered some interesting data:
70 percent of a serve’s ball speed is produced by the internal rotation and hand speed of the arm. To have a monstrous serve, a player should focus on these elements.
Sometimes, though, in an effort to accentuate forearm pronation, players mistakenly try to hit down on the hall. After all, this feels natural; almost all players are contacting their serves from well above the net.
However, in the early 1980s at the Vic Braden Tennis College, we did an interesting serve study. One of our students was Artis Gilmore, the 7-foot~2 former star center for the Chicago Bulls. Even at his extreme height, Artis was still too short to hit down on his serve.
http://goo.gl/dGZ5XB
Raul_SJ
G.O.A.T.
The serve is different than an overhead because you are able to hit down on an overhead at the service line. Hitting down is not possible at the baseline.
tennisdad65
Hall of Fame
Regarding the Pat Cash video (post 36 by SureshS).. Very surprising that a player of his caliber would pull his head down so quickly on the serve. He starts pulling his down while the racquet head is at shoulder height. If he was a club level player he would be told to keep his head up on the serve.
Chas Tennis
G.O.A.T.
Raul,
So it's concluded that one must hit up with the serve from the baseline? I have no problem with that concept and instruction
The article by Rod Cross on the kick serve has some information on the angle of the ball leaving the racket (often called 'projection angle' in biomechanics). Also, there is a video from the side. I believe the comments were about the kick serve. The article is hard to find now see above on this page "Improve- TW University - click on the "Top Spin, Side Spin, Gyro..." Spin - Physics of the kick Serve. http://twu.tennis-warehouse.com/learning_center/kickserve.php
"4. Downward force. The racquet head is rotating rapidly towards the net when the ball is struck. The racquet head rotates through an angle of about 10 degrees while the ball is on the strings. If the ball is struck when the head is vertical, then the ball will come off the strings when the head is tilted forward by about 10 degrees. The ball will come off the strings at an angle of about five degrees below the horizontal, rather than 10 degrees, since the force on the ball is a maximum half way through the impact, and is zero at the start and end of the impact. On average, the force on the ball acts in a direction about 5 degrees below the horizontal in that case. The serve angle also depends on the height of the ball toss and whether the head is rising when it strikes the ball. The serve angle is very important in a fast serve since an error of two degrees can result in a fault where the ball either hits the net or lands long."
"In a typical kick serve, the racquet head approaches the ball at about 65 mph and rises at an angle of about 5° just before impacting the ball. The amount of topspin in that case is about S = 1.45 × 65 × 5 = 471 rpm. If the ball toss is not right, and the ball is struck a bit further forward, the vertical approach angle of the racquet head might be only one degree, then the amount of topspin will be five times smaller. If the ball is struck a bit earlier, the approach angle might be 10° instead of 5° then the amount of topspin will double. However, if the ball is struck too early, then it might land on the baseline instead of the service line. Hitting up at a greater approach angle to the ball generates more topspin, but the ball is then launched at a higher angle over the net."
Comments on projection angle.?
Mostly looking at high speed videos, I'm still not sure what 'hitting up' means. Can we relate 'hitting up' to what is seen in high speed videos from the side view?
Also, the general view and the article emphasize the closing aspect of the racket's rotation. The racket also rotates more rapidly around a more vertical axis from ISR, as can be seen in the 6000 fps video above.
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Exactly what I said about the possibility of the racket coming uover and down the cusp in the dwell time.
He should take some FYB courses
Vic Braden study that says a 6' 8" player cannot hit down on the serve might not be understood correctly. Fuzzy Yellow Balls had an analysis of Isner at 6' 9" and Will Hamilton (fyb owner) at 5' 8". The analysis showed the ball flight from contact point to service box. From Isner's height at contact and forward lean into the court, he could hit a serve that just cleared the net and landed 7' (feet) inside the service line. The Isner serve flight line from contact with the racket to contact inside the service box was a straight line with a consistent downward trajectory. So, the study didn't indicate if Isner's stringbed was tilted slightly up or slightly down at contact but it did show Isner could hit a ball on a downward trajectory and land it well inside the court. From Will's height of 5' 8", the serve flight line from contact for a serve that just cleared the net, the serve landed precisely on the service line. So, if you are closer to Will's height, you better bend the serve with spin in order to have any margin that allows you a chance of getting the serve into the box.
Braden said there are 2 ways to get the serve to bend 1. gravity and 2. spin. Vic was big on spinning the serve to get margin because if you use gravity to bend the serve in the air, you must hit the serve very slowly to give gravity enough time to work.
Even Isner from his bird's nest way in the sky uses a lot of spin to bend the serve into the box.
To get spin that pulls the ball down, you must have a bit of topspin to pull the ball downward. Could be just a little like 8 to 2 o'clock rotation axis or it could be steeper topspin like 7 to 1 o'clock for more bend downward into the box. To hit a serve with any element of topspin, you must hit up on the serve. So, tennis players should hit up on the serve if they plan to get the serve into the box. We can debate if the racket makes contact on the way up and then finishes contact after the apex. Braden said you could get the sense of hitting "up and over the ball" at contact, but the point is you must be hitting up a bit to get any element of topspin at contact.
Braden said there are 2 ways to get the serve to bend 1. gravity and 2. spin. Vic was big on spinning the serve to get margin because if you use gravity to bend the serve in the air, you must hit the serve very slowly to give gravity enough time to work.
Even Isner from his bird's nest way in the sky uses a lot of spin to bend the serve into the box.
To get spin that pulls the ball down, you must have a bit of topspin to pull the ball downward. Could be just a little like 8 to 2 o'clock rotation axis or it could be steeper topspin like 7 to 1 o'clock for more bend downward into the box. To hit a serve with any element of topspin, you must hit up on the serve. So, tennis players should hit up on the serve if they plan to get the serve into the box. We can debate if the racket makes contact on the way up and then finishes contact after the apex. Braden said you could get the sense of hitting "up and over the ball" at contact, but the point is you must be hitting up a bit to get any element of topspin at contact.
Just like me:
"There are two things which can bring it down if even it is hit up (as in second serve): gravity and top spin"
Chas Tennis
G.O.A.T.
Gravity -
Here is a gravity calculator for metric or Imperial (Feet);
http://keisan.casio.com/exec/system/1224835316
You can enter the time of flight from impact to bounce for the serve and it will give you the drop produced by gravity. In addition, the ball drop from the toss gives the ball a downward velocity before impact. I don't know what the time of flight between impact and bounce is. I put 0.5 seconds in the calculator and the drop from gravity was over 4 feet or over a meter. What is the travel time for high level serves?
The points you make about the racket going up at impact are good ones and I've seen the interaction in videos, I agree. The hit is up for the flat and slices serves to some small degree and more so for the kick serve. But was that what Tomaz meant or what most understand by "hit up on the ball"? Why would he show those Raonic frames from the side view, showing racket closing, if he meant that? Tomas does not take high speed videos to display serves, no racket paths, at impact, correct? Impact involves the racket path during impact as best seen from behind using high speed videos. But the hit is also across to produce sidespin. Cross says that the kick serve has more sidespin than topspin.....but more topspin than the flat or slice serves. Those were surprising statements for me.
Also, the clock face terms '7 to 1' and '8 to 2' are misleading and servers should not take them as literal instructions without high speed video confirmation, especially for the kick serve. Is the clock face vertical and horizontal or perpendicular to how the server is looking? The spin axes for each serve type have a component of topspin, sidespin and gyro spin as explained in the Cross article and much better in his book. How do the clock face terms describe the the 3D nature of of the axis direction, especially the gyrospin component?
This is another case where some early term, 'hit up on the ball', was widely used. The usage became well established well before research showed that the serve was really very different (because of internal shoulder rotation) than understood, for example, during most of Braden's work, before the late 90s. Does 'hit up on the ball' refer to how the racket face is open but closing approaching the ball? Or to the lateral upward and horizontal string motion that actually causes the racket to go up and to the side during impact, a more complex and accurate description. That is caused by a hitting 'up' in a way. But no one can use those words - 'hit up on the ball' - to understand impact without proper high speed videos to show the actual racket-ball impact. I don't think the phrase, 'hit up on the ball', has been defined anywhere. Terms are very useful to refer to subjects but reading too much into them can be very misleading, especially if the term is not defined anywhere.
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Chas, I read Braden's book and I have read your ISR article. I think your ISR article is excellent but I think what Braden understood and taught is consistent with ISR concepts that you advocate. I don't think your ISR article would have opened any eyes even in the 1990s. The best players have been feeling ISR and using it if not calling it ISR for decades. The concept of forearm pronation has been understood to be a key part of the serve for many decades. Braden also taught that shoulder rotation to whip the arm forward and into contact was a key element to the serve. ISR may not have been the term used in the 1970s but the concepts are the same to me. But, your method of explaining it and your ISR article are good. But, I view them as simplification of existing concepts more than a major breakthrough in serving technique.
I don't know if Tomaz meant the racket face should be pointed up at contact. I for one think it is actually possible to hit up at contact with the face slightly closed at contact to achieve a degree of topspin on the serve just like you can hit a FH groundstroke with an upward swing path and closed face to achieve topspin.
Chas Tennis
G.O.A.T.
I have a high speed video from 1919 showing a strong server doing ISR. He was known as a very strong server, "the Human Catapult",........ I don't know what percentage of the highest level tennis players used ISR in 1919. The second serve is in slow motion. Anyone have high speed video of some of the other prominent players?
The joint motion of forearm pronation, powered by very small muscles, is not the joint motion and muscles used to accelerate the racket. In the late 1980s, I can recall studying pronation of the forearm and can remember then and later looking up at the ball and rotating the racket to face the ball, probably using my forearm with its small muscles. Some of the posters are doing the same weak and pointless motion now, also because forearm rotation without an angle between the forearm and racket develops no racket head speed from rotation. In the information age with Google it's time to start using terms that don't mislead anyone especially new people who look up the terms.
The major break through was in the 1990s with the research and publications of Elliott et al. I believe that it was recognized and acknowledged by a few knowledgeable researchers but not by tennis players, or most coaches or instructors. Earlier research had established the importance of ISR for badminton and baseball. The badminton researchers even communicated that the tennis serve was also powered by ISR. Elliott et al have been active in teaching mostly tennis instructors and coaches. Still, it is hard to understand ISR or hear the term from the majority of instruction books or videos. 20 years after 1995, what percentage of tennis players can discuss ISR?
About 40% or more of the posters have Waiter's Tray serving techniques. I don't think that the serve is well understood. Young serious junior players are being taught how to perform the ISR serve, apparently by a number of coaches.
I think describing the complex 3D interaction of the racket and ball - that changes by a few degrees every millisecond - with a few words, 'up, down, forward,' etc. and not looking at high speed videos to confirm our views or showing them to support our points of view always insures arguments over these simplistic descriptions.
I think that if someone reads the ISR article that they will have an understanding of ISR, get through the membrane once and for all.....
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heninfan99
Talk Tennis Guru
I don't like this concept. Didn't work for me.
Raul_SJ
G.O.A.T.
Not sure how to reconcile this with the Vic Braden College study that stated 7'2" basketball player was "unable to hit down" on the serve.
I interpret Braden's "hitting down" to be referencing the racket face is closed (tilted forward from the vertical) at the moment of initial impact and not to the ball flight path trajectory.
The FYB study showed a straight line from contact over the net and down into the court. The trajectory of the line was downward and completely straight. I am a big fan of Vic Braden and know he advocated hitting up and spinning the serve. Maybe the ball trajectory will be down but the racket swing path is up and out to reconcile the 2 concepts. But, to be honest, I think a 7' 2" guy who is good at serving and using their full extension could actually swing down and get the ball into the court. It is not something they should do as it would likely be a crappy service motion but I think it could be done. I cannot find the FYB study but I know I have cited it correctly. You could also simply draw it with graph paper by estimating contact height - I think Isner's contact height is around 11' - and draw the court, net and service lines.
Tight Lines
Professional
I am going to disagree with this. I think it's a very useful cue. Without it, most beginners will try to hit down on the ball.
Harry
donquijote
G.O.A.T.
Without making the correct routine (good toss, leg drive, jump inside the court, shoulder rotation etc), they will either hit it out of the court or they have to hit slow and/or with lot of spin to be able to land the ball in the box when they hit upwards (or as it feels so). Tomas is right that the timing has to be really good otherwise it will be a fault.
For a non-advanced player, I'd think a better drill would be tossing the ball behind your head so that you can learn hitting upwards with spin and that probably would also force someone to use the knees as well.
I also agree that it is a very useful teaching cue. Eventually, they will find out a way to bring it down into the box by themselves.
LakeSnake
Professional
You will see amateurs in any sport, art, or discipline suffering from typical technical errors. It doesn't necessarily mean the solution to those errors is obscure or unknown to the skilled practitioners or teachers. Usually there is a pathway, and it involves huge amounts of dedicated practice and many sessions with good teachers. Neither of these things is usually available to the casual learner because of time and cost requirements.
Chas Tennis
G.O.A.T.
This report is not easily readable and some of the terms are not specifically defined in the publication.
In particular, the term "Backward Tilt" with reference to the racket seems to say that the racket tilts open at impact by over 10°. I don't believe that tilt angle is typical of serves based on my qualitative estimates of impact frames of ATP servers that nearly all seem to have much more vertical racket tilt angle. ?
Later, the publication discusses 'projection angle', the the ball's trajectory in relation to the horizontal, plotting serves in the net and good serves versus impact height, ball velocity and projection angle. A very interesting plot. They have 3 categories of Australian female servers including a single very high level WTA server, not named, ranked at #4 when the research was done. Stosur?
Anyway, this kind of research can be found using Google Scholar: projection angle tennis serve
A kinematic comparison of successful and
unsuccessful tennis serves across the elite
development pathway
David Whiteside, Bruce Elliott, Brendan Lay, Machar Reid
abstract
While velocity generation is an obvious prerequisite to proficient
tennis serve performance, it is also the only stroke where players
are obliged to negotiate a unique target constraint. Therefore, the
dearth of research attending to the accuracy component of the
serve is surprising. This study compared the body, racquet and ball
kinematics characterising successful serves and service faults,
missed into the net, in two groups of elite junior female players
and one professional female tennis player. Three-dimensional
body, racquet and ball kinematics were recorded using a 22-cam-
era VICON motion analysis system. There were no differences in
body kinematics between successful serves and service faults, sug-
gesting that service faults cannot be attributed to a single source of
biomechanical error. However, service faults missing into the net
are characterized by projection angles significantly further below
the horizontal, implying that consistency in this end-point param-
eter is critical to successful performance. Regulation of this param-
eter appears dependent on compensatory adjustments in the distal
elbow and wrist joints immediately prior to impact and also per-
ceptual feedback. Accordingly, coordination of the distal degrees
of freedom and a refined perception-action coupling appear more
important to success than any isolated mechanical component of
the service action.
Download publication.
http://www.researchgate.net/publica...s_serves_across_the_elite_development_pathway
In particular, the term "Backward Tilt" with reference to the racket seems to say that the racket tilts open at impact by over 10°. I don't believe that tilt angle is typical of serves based on my qualitative estimates of impact frames of ATP servers that nearly all seem to have much more vertical racket tilt angle. ?
Later, the publication discusses 'projection angle', the the ball's trajectory in relation to the horizontal, plotting serves in the net and good serves versus impact height, ball velocity and projection angle. A very interesting plot. They have 3 categories of Australian female servers including a single very high level WTA server, not named, ranked at #4 when the research was done. Stosur?
Anyway, this kind of research can be found using Google Scholar: projection angle tennis serve
A kinematic comparison of successful and
unsuccessful tennis serves across the elite
development pathway
David Whiteside, Bruce Elliott, Brendan Lay, Machar Reid
abstract
While velocity generation is an obvious prerequisite to proficient
tennis serve performance, it is also the only stroke where players
are obliged to negotiate a unique target constraint. Therefore, the
dearth of research attending to the accuracy component of the
serve is surprising. This study compared the body, racquet and ball
kinematics characterising successful serves and service faults,
missed into the net, in two groups of elite junior female players
and one professional female tennis player. Three-dimensional
body, racquet and ball kinematics were recorded using a 22-cam-
era VICON motion analysis system. There were no differences in
body kinematics between successful serves and service faults, sug-
gesting that service faults cannot be attributed to a single source of
biomechanical error. However, service faults missing into the net
are characterized by projection angles significantly further below
the horizontal, implying that consistency in this end-point param-
eter is critical to successful performance. Regulation of this param-
eter appears dependent on compensatory adjustments in the distal
elbow and wrist joints immediately prior to impact and also per-
ceptual feedback. Accordingly, coordination of the distal degrees
of freedom and a refined perception-action coupling appear more
important to success than any isolated mechanical component of
the service action.
Download publication.
http://www.researchgate.net/publica...s_serves_across_the_elite_development_pathway
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Raul_SJ
G.O.A.T.
Raul,
So it's concluded that one must hit up with the serve from the baseline? I have no problem with that concept and instruction
Yes, I believe you need to hit up on the serve. My observations on typical 3.0/3.5 matches is that the vast majority of service faults are hit into the net. This is an indication that players are contacting the ball with an overly closed racket face.
I think the biggest single error that people make on their serve, at the rec and pro level has more to do with their feet than anything else. They transfer their weight to their front foot way too early in the motion. Your toss arm should be fully extended before your weight even begins to move forward on to your front foot. It is so common to see peoples tossing arm go up as they shift their weight on their front foot. The delay needs to be much greater than you think. This will fix the vast majority of service errors. If you do this everything else falls into place. It is not an easy thing to correct, but is well worth the effort. If you keep your weight leaning back, on your back foot through the entire toss, you will find your toss will always be in the proper position to contact the ball properly. And you can use your body more effectively, and you won't have to think so much about the other stuff.
Chas Tennis
G.O.A.T.
Raul,
So it's concluded that one must hit up with the serve from the baseline? I have no problem with that concept and instruction
For the player level from 3.0 to 4.5, probably 40% or more of the servers are using the Waiter's Tray technique, with little or no ISR for racket head speed.
How do you factor that into your comments? To what serving technique do your comment apply?
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Graph showing Isner 11' contact 2 feet into court and how it clears the net:
Very good point here about too much weight on the front foot. I see a lot of rec players that lean in too much, get off balance and kind of drag the racket head through contact as they fall into the court instead of pushing weight up into contact. Related to this, you see a lot of just general balance issues on serve where players chase the toss L or R or lean back or forward. I think a lot of players could benefit from simply serving with their weight balanced between their shoulders when they start the forward swing. Watch youtube of Federer for platform and Ferrer for pinpoint examples of very balanced position as the base for forward motion.
Very good point here about too much weight on the front foot. I see a lot of rec players that lean in too much, get off balance and kind of drag the racket head through contact as they fall into the court instead of pushing weight up into contact. Related to this, you see a lot of just general balance issues on serve where players chase the toss L or R or lean back or forward. I think a lot of players could benefit from simply serving with their weight balanced between their shoulders when they start the forward swing. Watch youtube of Federer for platform and Ferrer for pinpoint examples of very balanced position as the base for forward motion.
I can't believe people are debating this. Yes, you're not actually hitting the ball UP (of course) but the throwing motion is up - why is that hard to understand? You throw the racquet as if you were trying to get about a 70 degree angle up and you're trying to make the racquet flip (end over end) as fast as possible. Contact corresponds exactly to the release point of the racquet, in the imaginary throw, which means the head of the racquet is rotating forward and achieves an angle, all by itself, so that the ball goes forward and maybe down a little. By the way, you can't it the ball up even if you tried because the racquet head is rotating forward as you go into contact.
Yes he does, even more actually.
That's pretty much it - not sure why people don't get it.
First, you ARE actually hitting up on the ball on second serves and second-serve-like first serves. Second, it is not a debate, but a discussion to see what really happens at contact.
Yes, the serve is the same as an overhead smash from the baseline. If the overhead is closer to the net, you'll make your contact point further in front so that the racquet (pivoting on the wrist) is point down more and hence, sends the ball downward more. If you're having to back up to get the overhead then you'll help the racquet head around by snapping the wrist - you don't need to do that on a serve because you toss the ball in front of you.
Maybe we have a translation issue - I said ,"you're not actually hitting the ball UP " - that is not the same as "hitting up on the ball". And you hit up on the ball on ALL serves not just topspin serves.
"Hit upwards" - that has to be defined. I'll do it. "Hitting upwards" - the upward throwing motion in a tennis serve such that if the racquet were released at contact it would fly upwards, flipping end over end, at an angle of about 70 degrees (90 degrees being straight up). This definition applies only to a flat serve. Does that solve the mystery for anybody?
The serve more than any stroke is a kenetic chain. The arm will start to move properly if the the legs and hips move correctly. I think we just put way too much emphasis on the arm from the start, which down the line sabotages ones efforts. If you shift your weigh back and keep your arm by your side it will naturally fall backwards which puts your arm in the proper position to hit the ball. This is an admitted oversimplicification.
Although he's always super balanced, I think Federer actually often gets too much weight forward too quickly. He could add 10mph easily with a slight adjustment. Yes....I said that.
The best example for platform is Raonic or Sampras. They keep their weight way back through the toss. And Isner and Querrey for pinpoint.Chas Tennis
G.O.A.T.
This video shows the ball on the strings, racket face closed, a little after initial impact where the racket may have been open. The video illustrates how rapidly the racket face is closing. At 240 fps it's 4 milliseconds between frames. I see mostly about vertical and don't know if a few degrees open or closed for initial impact applies to the average good serve.
To examine stop-action single frame - you can do stop action if you go to Vimeo's website by pasting - hXttps://vimeo.com/53440915 - in the URL address box above. Remove the X. For single frame, hold the SHIFT KEY and use the arrows (similar to Quicktime).
Open or closed is a very close call using 240 fps video.
Do you mean 1) the racket tilt angle points up at impact or 2) that the path of the strings in contact with the ball is upward? Do you have any video evidence or research to show why you are confident that "And you hit up on the ball on ALL serves not just topspin serves."?
I agree if you mean the string path is somewhat upward for the flat and slice serves and considerably upward for the kick serve. I don't know what the racket tilt - opened or closed - is for initial contact. I don't think anyone on the forum knows that based on high speed video observations. If you have some evidence for this interesting issue please post.
For slow serves like most rec players have (<80 MPH vs 120 MPH) the ball has to have a higher projection angle to get it over the net because gravity has more time to bring the ball down. The racket face more open at impact might be a benefit for slower serves, especially the very common Waiter's Tray technique.
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1) no the racquet does not not point up at impact
2) no the path of the strings is not upward at impact
I guess technically you could say the the wrist is going up and the racquet is being rotated such that at contact, the racquet face is vertical and the wrist has stopped it's upward movement. However, if the racquet is release precisely at contact, the racquet will still fly upwards, flipping end over end. The ball is contacted at the apex of the upward throw, or very close to it.
All you have to do is have a good server release their racquet at contact - the racquet will fly up - that will be your evidence.
