power of the racquet and serve

Discussion in 'Tennis Tips/Instruction' started by taurussable, Sep 21, 2013.

  1. taurussable

    taurussable Professional

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    I can rarely first bounce to fence with a mg rad mp.. but I can do it with a lm rad os more easily. does someone has similar experience regarding power of the racquet and serve velocity?
     
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  2. SystemicAnomaly

    SystemicAnomaly G.O.A.T.

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    Yes, a more powerful racket can undoubtedly can produce more powerful (faster) serves. The problem with a very powerful racket is that it makes it more difficult to keep the groundstrokes from going long -- depth control is more of a challenge with a power stick.
     
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  3. Roger Wawrinka

    Roger Wawrinka Professional

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    Try a pure drive or an aero pro drive, you'll see a difference.
     
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  4. Topspin Shot

    Topspin Shot Legend

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    Yes, a more powerful racket can make a difference on your serve. Not a huge difference, but somewhat of a difference. I feel like my Prestige Pro makes my serves pop more, which is one of the reasons why I like it so much. Babolats will also give your serve more power. The thing is though, the Radical MP in your signature is much heavier than a stock Radical MP. With all that lead, the racket may be too heavy for you. You may have added all that lead to make the racket have a bigger sweetspot, but the weight may be slowing your serve down. Try a Babolat and see what you think. It can't hurt just to try, and you may be pleasantly surprised.
     
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  5. Roger Wawrinka

    Roger Wawrinka Professional

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    I would also note that the stiffness makes a big difference.
     
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  6. taurussable

    taurussable Professional

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    the mg rad is soft, way too soft with all the lead. You can feel the hoop flex when you bounce tennis ball on it...
    http://www.youtube.com/watch?v=mIgLO2s8ISI
    is the serve i've got with it. Really attempted to try a powerful racquet.
     
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  7. ChicagoJack

    ChicagoJack Hall of Fame

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    Oh man, I don't know where to start. I could (and have) posted for weeks on this topic, yet I've only scratched the surface. Almost everything you'd want to know about about racquet power and serve speed can be found right here in the TW University.

    Short version is that stiffness is a factor, but it's a relatively minor one. The two biggies are racquet head speed and swingweight. Yes, I know the other factors well ... overall mass, beam width, twistweight, recoilweight, string tension, string stiffness, string pattern, head size, racquet length. They all play a role, but they are dwarfed by the 2 largest factors which (stated again for emphasis) are racquet head speed, and swingweight.

    I posted a little bit on the basics of ACOR / Racquet Power in a similar thread here,. Might wanna give that a quick look see. Of particular interest to the OPs question, see posts #12, 13, 24, 34, 119, 121, 223, 228 ... as well as Corners' excellent posts # 111, 117, 147, 148, 151

    Also this thread here : See my posts #23, 25, 44, 54, 56

    -Jack
     
    Last edited: Sep 21, 2013
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  8. LeeD

    LeeD Bionic Poster

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    After I had my MGRadOS for a month, and I was using it maybe once every couple of weeks, and old fart at our local courts showed up with a MGRadMid in his bag, as he played with the newer IGRadOS.
    I tried his racket a few shots. I can hit everything harder with his mid than I can with my OS. So I tried HIS OS. I still hit harder with his Mid.
    Have since settled on Dunlop4DAero300's, a close clone to the MGRadMid.
     
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  9. sureshs

    sureshs Bionic Poster

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    Only if the server can swing it fast
     
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  10. TomT

    TomT Hall of Fame

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    As other posters have mentioned, and as I've experienced, the specific racquet that you're serving with can make a difference.

    But here's the thing. If you have a fairly decent serving motion, with fairly decent weight transfer and contact point, then you should be hitting a few feet up on the back fence on the first bounce, at will, with ANY racquet.

    If you can't do that, then my two cents is that the immediate problem isn't which racquet to use, but rather to do the work necessary to improve the serve so that you can do that.

    When you can do that, and after sampling several other racquets I think you'll come to the conclusion that, while the racquet can/does make a difference, the difference isn't significant enough to make a difference.
     
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  11. SystemicAnomaly

    SystemicAnomaly G.O.A.T.

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    I believe that a majority of "power" rackets tend to have a low/moderate static weight or swingweight. Exceptions???
     
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  12. Baxter

    Baxter Professional

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    I play with a bunch of different rackets, from woodies to brand new, and the serve is the stroke least impacted the racket, IMO.
     
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  13. ChicagoJack

    ChicagoJack Hall of Fame

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    1. The higher the swingweight, the higher the inherent raw power of the frame. The lower the swingweight, the lower the raquet power. Grossly simplified ... ACOR/Racquet Power + Racquet Head Speed = Ball velocity. The inherent raw power of the frame is called ACOR (Apparent Co-efficient of Restitution). It is determined by measuring the rebound speed of the ball after it impacts the string bed. As it turns out, (if the swing speed is constant) the higher the swingweight the faster the rebound speed. That is why, in the screen grab below, you will see that the extremely heavy, (and yet very flexible) Boris Becker 11 is by far the most powerful frame. Vastly more powerful than the stiff and lightweight frames. Keep in mind these impact studies performed at 13 different locations on the string bed were obtained using real balls, and real racquets, this is not a hypothetical extraction. Yet we still have to swing these very heavy frames, so that is where the question of racquet head speed and player technique comes into play.

    2. The biggest gains (on paper) with regards to increasing power would come from increasing mass, while keeping racquet head speed constant. If you could do that, switching from a 250 gram racquet to a 400 grams racquet results in a 15% increase in ball speed on a 100 MPH serve. So you'd get a pretty big bump up to the vicinity of 115 MPH. However, it's safe to assume it's not possible to swing a 400g racquet as fast as a 250g racquet.

    3. Informal recent studies have noted that when you throw a test group of players onto the court, and steadily increase the sw, the velocity of the ground strokes steadily increased, but the serves did not. Simple explanation for that. It is reasonable to assume that as mass increases, maximum RHS drops. In a serving motion we are already swinging as fast as we can on both first as second serves. All that really changes if your technique is good is that the second serve has more spin. So, in the serving motion, where you are already swinging for the fences, there is much less room for improvement in serving speed by adding mass. We also know from the study of hi speed film that the speed of the tip of the frame is always traveling about as fast the serve. Think about that for a fat second. What this means is that serve speed is almost directly related to the speed of the swing. In other words, directly from the players arm. Careful racquet selection might make a difference of a few MPHs, but serving speed is mostly about racquet speed. So the easiest way to get a 1% increase in serving speed, is to simply swing the racquet 1% faster.


    [​IMG]

    References, Links, Suggested Reading:

    Link [1] Basic Facts about Frames and Strings,
    The United States Racquet Stringers Association
    http://www.racquettech.com/top/basic_facts.html
    http://www.tennis-warehouse.com/lc/basicfacts.html

    Link [2] Raw Racquet Power, By Rod Cross
    http://www.racquetsportsindustry.com/articles/2006/02/raw_racquet_power.html

    Link [3] Racquet Handle Weighting And Maneuverablility, by Rod Cross
    http://www.racquetsportsindustry.com/articles/2006/04/racquet_handle_weighting_and_m.html

    Link [4] The Inch That Changed Tennis Forever, By Rod Cross
    http://www.racquetsportsindustry.com/articles/2006/01/the_inch_that_changed_tennis_f.html

    Link [5] Racquet Power Comparison Tool
    http://twu.tennis-warehouse.com/cgi-bin/comparepower.cgi

    Link [6] The Physics And Technology Of Tennis
    http://www.tennis-warehouse.com/The_Physics_and_Technology_of_Tennis/descpage-PHYSICS.html

    Link [7] Mark Philippoussis Service Speed Testing:
    Averages 124 MPH with a Wood Racquet, and 126 with his Graphite Racquet,
    Time Magazine, June 2009
    http://www.time.com/time/magazine/article/0,9171,1899876,00.html

    Link [8] Power Potential, The Total Performance Measurement
    http://twu.tennis-warehouse.com/learning_center/totalperformance.php

    Link [9] The Ingredients Of Maximum Shot Speed
    http://twu.tennis-warehouse.com/learning_center/maxspeedeasy.php

    Link [10] Maximum Shot Speed, Where to Hit on the Racquet
    http://twu.tennis-warehouse.com/learning_center/maxshotspeed.php

    Link [11] Why Is Maximum Power In the Throat and Maximum Shot Speed Toward The Tip?
    http://twu.tennis-warehouse.com/learning_center/PPandspeed.php

    Link [12] Compare Racquet Shot Speeds (Mph)
    http://twu.tennis-warehouse.com/cgi-bin/comparespeed.cgi

    Link [13] Compare Racquet Trajectories
    http://twu.tennis-warehouse.com/cgi-bin/trajectory_compare.cgi

    Link [14] More Tennis Physics, Rod Cross
    http://www.physics.usyd.edu.au/~cross/presentations.html

    Link [15] Power, Does the Racquet Matter?
    http://twu.tennis-warehouse.com/learning_center/racquetcontribution.php

    Link [16] Power Potential Test Procedure
    http://twu.tennis-warehouse.com/learning_center/test_method.php

    -Jack
     
    Last edited: Sep 22, 2013
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  14. SystemicAnomaly

    SystemicAnomaly G.O.A.T.

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    ^ The "power" rackets that I am referring to are the powerful "old man/lady" rackets for players with very short swings and a slow/moderate swing speed. These rackets typically have a low/moderate weight & swingweight and derive their power from frame stiffness and other factors.

    My experience says otherwise. Try Federer's or Novak's racket and compare it to the Head Ti.S6 racket for the serve. Huge difference I would imagine.
     
    Last edited: Sep 22, 2013
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  15. ChicagoJack

    ChicagoJack Hall of Fame

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    Yeah cool, I get what you are saying, that's a common idea. The Granny Stick/Snow Shoe/Walmart special is the "power" racquet, because it is lighter, stiffer and has a huge head. But we have all ready done this kind of testing, and the results don't support the idea that stiff, light, and larger head frames make for meaningful difs in maximum serve speed. In 1997, in a test sponsored by tennis magazine, Mark Philippoussis averaged 122 mph with a classic wood racquet where flex is in the the 30's-40 ra and a 72 Sq. inch head. With his own graphite, (stiffer, larger head) he averaged 124 mph. See quote below. (or any of my 16 other references) I'm not making this up. It is not a personal theory or idea. It is just the basics.

    [..]

    Quote: " The tale of what tennis did not become begins with the racket, perhaps the most misunderstood implement in the history of sports. The composite, or “graphite,” racket, made from carbon fibers and other materials including Kevlar, took over the game in the 1980s. Composite rackets are routinely cited as the villain behind the surge in power in tennis, yet it is these rackets that saved the game from becoming an utterly boring one.

    The fact is that composite rackets help players hit better ground strokes, impart more spin, and return rocket serves, but they do very little to speed up serves. In 1997, in a comparative test done by Tennis magazine, Mark Philippoussis, the six-foot-five, 217-pound Australian renowned for his powerful serve, averaged 124 mph when serving with his own composite racket. With a classic wooden racket, he averaged 122 mph.

    Scientists explain this using a simple formula: ball velocity after impact divided by ball velocity before impact (the racket must be suspended freely or held firmly in hand, not clamped in place). The resulting number, called ACOR, for Apparent Coefficient of Restitution, is an indicator of how much energy a racket loses when it collides with a ball. If a ball approaches a racket at 100 mph and bounces off it at 40 mph, the ACOR is 0.4. A racket with a higher ACOR is a racket with more power. Crawford Lindsey, a partner at the United States Racquet Stringers Association and co-author of the influential Physics and Technology of Tennis, points out that wooden rackets, because of their greater weight, have a greater ACOR than most of the composite rackets on the market today (though only when struck dead center). Top players serve so much faster today not because of their rackets but because of their raw physical power. Male professional tennis players have grown roughly two or three inches taller and fifteen to twenty pounds heavier in the last thirty-five years, according to International Tennis Federation data.

    While the racket does not impart speed to the serve, it has a lot to do with the accuracy and pace of forehands and backhands. Stiff carbon fibers produce a structurally sound racket at a lighter weight than wood—as little as nine ounces compared with fourteen or fifteen. Additional weight placed along the head, away from the handle, improves stability and prevents the racket from twisting or bending backward upon impact. As a result, the racket returns more energy to the incoming ball. It also has more power—a greater ACOR—for off-center hits. Put simply, it has a larger “sweet spot.”


    -- Spin Doctors, The Atlantic Magazine, July 1, 2006
    By Tom Perrota

    Nutshell: If the above epic tale does not make sense to you, recall my original, single premise. Ball velocity is almost directly related to swingweight + racquet speed. Most wood frames are 13-15 ounces and evenly balanced. That pushes the swingweight out to 350-360, about where most pro frames are today. Scud is able to get within 2 mph of his top speed with a woodie, because the swingweights are probably very close. And with a serve, most of the ball speed comes from the players arm. There is almost a direct relationship btwn the speed of the tip of the frame and the speed of the outgoing ball. If the speed of the tip of the frame is 110, the ball will be traveling pretty close to 110 mph.

    - Jack
     
    Last edited: Sep 22, 2013
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  16. SystemicAnomaly

    SystemicAnomaly G.O.A.T.

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    ^ It could very well be dependent on who is serving. Timing, technique, anatomy, string tension, etc have a lot to do with how fast or how much power a given server can generate. The specs you provided and the testing that you have referenced only tell part of the story. I do not believe that it provides an absolute truth for all players.
     
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  17. Larrysümmers

    Larrysümmers Hall of Fame

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    i find people with higher powered rackets seem to put less effort in their serves than people with lower powered. pdr was so easy and with the prestige mid really have to put some oomph into it
     
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  18. HughJars

    HughJars Professional

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    Rackets and serving are a really touchy subject for me...Ive tried for extended periods new rackets that feel great on ground strokes (Extreme Pro 2.0, Wilson Tour, Wilson BLX Fierce FX and Babolat Aero Pro Lite) and fantastic on the return game , but I still cant go past my piece of crap 8 year old $100 Dunlop M-Fil on the serve. It just feels like home. Groundstrokes its horrible - no power, unstable, stiff as a board. But it open stringed, and light and just fits perfectly with my serve, and I havent been able to find anything weighted exactly like it.

    Its like an ex-girlfriend - you know her inside and out. All the things you like...and all the things you hate...and you keep finding yourself going back to her cos you know what youre gonna get...

    Anyway...

    So Im in a Catch 22 when I play now - do I take out old faithful which I KNOW will give me a strong service game, or do I use my new rackets to help my ground strokes and return games and risk losing my serve?

    My first serve is an important component of my game. I find when I lose my serve it affects my whole game. Im very much a confidence player.

    And for the upcoming club season - do I stick with old faithful to the detriment of my ground game, or hope I can eventually find a groove on the serve with my newer racket (currently using the Babolat Aero Pro Lite)? When I land the serve with the Babolat its great, kicks like a mule with plenty of pace. But currently the consistency isnt up there with my old one.

    Hell, Ive even considered swapping rackets for my serve and return games - has anyone ever done this???
     
    Last edited: Sep 22, 2013
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  19. ChicagoJack

    ChicagoJack Hall of Fame

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    Yeah .. Almost anything I post here on racquet power, and max serve speed will be incomplete and will only tell part of the story. It's a big story! I can only post as much as a hectic life permits me. That's why I've posted 16 or so links. Its all there, read! :) ... and its easier than me explaining all of this. I'm only offering the rough basics. However, just a few quick thoughts fer ya here on my lunch break.

    1. Agreed. If we are discussing racquet selection, there is no absolute truth as to which racquet will create maximum serving speed for every player. The closest thing to an absolute truth is the age old axiom which has stood the test of time for decades: "The most powerful frame is the heaviest racquet you can still swing fast". That is why there is currently a ginourmous range of sw, balance and overall mass out in the current market place. Players have differing levels of fitness, conditioning, height, weight, muscle mass and limb length etc. Good old Newtonian physics plays a role here, I'll get to that later. However, when a player is talking about "racquet power" he or she usually has in mind the inherent power of the frame that is separate and distinct from whatever fitness or technique he brings to it. From that context, when we do the lab testing that just involves racquets, balls and measuring rebound speed, there are observable facts, which can be found in any of the dozen or so links I have provided.

    2. There is a concept called "Racquet Power" which is entirely separate and distinct from the player, his talent, and his skill level. This is exactly what the OP is wondering out loud about ... if I switch to a more powerful racquet, I'm still the same guy, but will I able to serve faster? Well, you need to understand something about racquets with the player out of the equation first. We will plop him back in there later, but racquet power is just the first section of racquet power + swingspeed = ball velocity. When you fire balls at freely suspended racquets, and measure the rebound speed, it turns out that as swingweight is increased, rebound speed is increased proportionately, and is by far the largest factor. Stiffness matters only slightly and only for impacts off center. Hit anywhere near center, and a flexible frame is just as powerful as a stiff frame. All things being equal, a flexible frame is never more powerful than a stiff frame, because bending and vibration represent energy loss. But when you hit center, there is very little bending and vibration occurring, and the impact is very efficient. That's not entirely accurate, as you might recall from elementary school science class that energy is never lost it is merely converted. In this case, vibration represents energy being converted into friction and heat, and other stuff not very useful for making a ball go fast. So this is why stiffer frames are slightly more powerful, (about 2-3% max) but only in the places where mishits occur and vibration is very pronounced. Hit anywhere near the tip and the sensation isn't pleasant at all. Stiff frames suffer less energy loss at the tip, and way out at 3-9. Some might call this "more power" others might describe this as larger sweetspot, or less power drop off.

    3. But nobody is leaving players out of the equation. Racquet Power/ACOR is merely the first thing to understand clearly, when we are attempting to understand maximum ball velocity out on a tennis court. We know that hi sw frames are more powerful low sw frames. The biggest gains on paper would come if we assume swing speed remains constant, and mass increases. In that case, switching from a 250 gram racquet to a 400 grams racquet would mean an increase in max serve speed by 15%, so if you topped out at 100 mph, you'd now show 115 on the radar gun. That is an impressive gain but not entirely realistic. Notice how the conversation has shifted just a little bit? We are now left with a puzzler. Can I really swing a heavier racquet just as fast? The answer is two fold. On groundies, the answer is probably yes. On serves, the answer is probably no, you probably can't swing that heavier frame just as fast. But hold that thought. Sir Issac wants to chime in here and explain why.

    4.

    F=MA ( Force = Mass times Acceleration)

    This simple Newtonian equation is present every time we pick up a cup of coffee, swing a baseball bat, launch a rocket into outer space or swing a racquet, and is incredibly revealing if you study it closely. Notice that if the mass of the racquet is doubled, the force required to achieve the same acceleration is doubled. Said another way, if the mass is doubled, and the force remains constant, acceleration will be halved. I'm just a dumb jock at heart. The dumb jock in me translates that last version into tennis terms something like this: If I switch to a racquet that is twice a heavy, and the force available to swing that racquet remains constant, (because I still have the same muscles) then my maximum swing speed will be cut in half. So ... on a serve you can swing a heavier racquet with more rebound power, but your max swing speed will be reduced proportionately. Or, you can swing a lighter, less powerful frame faster, but the racquet has less rebound power in it. It's a wash at the end of the day. This explains why, on real tennis courts, with real players, max serving speed stayed about the same as sw was steadily increased. For a serve, we are most likely already swinging as hard as you can. Or at least that is what you are doing if your technique is correct. With a second serve, the racquet should still be traveling at top speed, but you just adjust the racquet face to create more spin, which gives you much better odds that the ball will clear the net, and land inside the box. So ... the added mass on the serve probably means that acceleration decreases. You can swing faster with a lighter frame, but the lighter frame will have less Pop to it. You can swing a heavier frame with more inherent rebound power, but your swing speed will drop. Newton pays you a visit, and it's basically a wash.

    5. In that same study however, velocity of ground strokes increased as sw was increased. So, why does added mass do little for maximum serve speed, yet seems to increase groundstoke MPHs? Groundies are another story, because you are not always swinging as fast as you can on groundies. Most times you are intentionally dialing down your swing speed to gain consistency. You might unleash your most fierce FH if your guy is rushing the net, but swinging as fast as you can on every groundie will often produce a bunch of unforced errors. So the added mass on a ground stroke is something that the player can probably adjust to. The racquet might be a bit heavier, but he is able to swing at he same speed and timing that hes is grooved to because he has some muscle strength "in reserve" so to speak. You might feel differently about the added mass in a fifth set tie breaker on a hot and humid day, so this is where fitness plays a role.

    6. Yes, string tension plays a role. Probably not as much as we think, given all the references to "Rocket Launcher" and "Bazooka" I see around here. (eye roll) When the book "The Physics And Technology of Tennis" was written a decade ago, it was estimated that for every 10 lbs drop in tension you'd get 1% increase in ball velocity. More recent testing on real courts with real players indicates about 2 -2.5 % (on average, and depending upon the stroke) increase for every 10 lbs using syngut string. Probably not the huge difference most players talk about, but still meaningful in my book. Mentally extrapolating the difs in say... Full gut at 40 lbs, and Kevlar at 70, I think string selection represents that largest area for "free" power that we have, because its just as easy to swing a racquet at 50 lbs as it is to swing a racquet at 60lbs. Suffice to say that Kevlar at 70 might cost you the price of one perfectly good arm, and full gut might cause your wallet to be a bit thinner.

    Nutshell : (For those who are skimming for a summary) Swingweight is almost directly related to Racquet Power. It is not the only factor, but it is by far the largest. This leads us to a conundrum, which is... can I swing that heavier racquet just a fast? The answer is two fold. Probably yes on groundies, though you might feel differently in a 5th set tie breaker. And probably not on a serve. Added mass will likely result in additional ground troke speed (or the option to swing slower and keep the same speed). But added mass is not likely to cause a gain in max serve velocity.

    -Jack
     
    Last edited: Sep 24, 2013
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  20. Overdrive

    Overdrive Legend

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    ^

    Too much reading! ;)
     
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  21. taurussable

    taurussable Professional

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    agree, off center hits on flex frame has significant drop in power.

    should I contact at center of frame or a little above center in serve?
     
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  22. LuckyR

    LuckyR Legend

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    ChiJack is correct in his overall premise which seems to be, swingspeed correlates directly with flat serve speed. He does a great job of describing the factors that impact swingspeed.

    Groundstrokes (and spin serves for that matter) are a totally different matter for the simple fact that except for overheads, spin plays a huge role in the "speed" of the stroke. Or to put it another way there is not a player on the planet that can't hit a "faster" groundstroke long, than what they can get to land in. Thus the rate limiter is not the stroke itself nor the racquet. Rather it is the ability to get the spin/pace ratio perfect enough to keep the ball from going long.
     
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  23. ChicagoJack

    ChicagoJack Hall of Fame

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    Oh hello again Overdrive (smile)

    Yeah, I know my audience. That's why I posted a summary conclusion at the very bottom. Maybe wasn't there on your first drive by, but it's there now. It's a big topic, tough to cover completely in as few words as possible, but I'm doing my best.

    Hi Lucky R -

    Yes, there's some extra nuggets in there, perhaps outside of my premise, but you have got the basic idea. I lump 2nd serves in with 1st serves, because if your technique is good you are still swinging as fast as you can on your second serves, just like you are swinging as fast as you can on your firsts. There isn't a coach in God's green earth who will tell you to swing slower and guide the ball into the court on a second serve. What you should do is swing the same speed and adjust the racquet face to create more spin. We know from the study high speed film, that on a serve, the speed of the ball and the speed of the tip of the frame are about equal. If the ball travels about 100 mph, the tip of the frame is traveling about 100 mph. This leads us to a rather bleak conclusion. That is to say, a racquet choice might make a slight difference of a few MPHs or so, but mostly all of the serving speed comes directly from the players arm. Again, racquet choice a probably a very minor factor overall, as evidenced by the 2 MPH difference on Mark Phillipoussis max serving speed with Wood Vs. Graphite racquets. If you want to serve 1 MPH faster, the best way to do that is to swing 1% faster.

    In case anybody is wondering why we are not still playing with wooden 72 square inch racquets, the big difference is not power. The big difference is spin, about 5 times more spin. See link below. 1980's gave us wider heads, which created the opportunity for faster swings and more extreme angles of contact. Late 90's gave us polyester strings, which create about 20% more spin than gut or nylon on average. But it wasn't until the the early 2000's when things began to really take off. We got a whole new generation of beefier, more physically fit players on the tour that were able to swing racquets fast enough to take advantage of this new technology. But the average junior hotshot who picked up a racquet in 2005 knows nothing of the historical evolution of tennis. All he sees is that Roddick, or Nadal or Jack Sock play(ed) with stiff frames, so stiff frames equal power. They have no idea (nor explanation) for the fact Colin Dibley's 148 mph serving speed record stood stood for 24 years before Roddick and Rusedski served up 149 and 150 MPH circa 1998.

    Link [4] The Inch That Changed Tennis Forever, By Rod Cross
    http://www.racquetsportsindustry.com/articles/2006/01/the_inch_that_changed_tennis_f.html


    -Jack
     
    Last edited: Sep 24, 2013
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  24. ChicagoJack

    ChicagoJack Hall of Fame

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    Aug 11, 2005
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    2,265
    Hi Taurussable -

    Yes. If all things are equal... a stiffer frame means more power (or slightly less drop off if you prefer) at the edges primarily near the tip, by about 1-3 percent. See screen grab. Look at the rebound speed of the YT Rad Pro vs the APDGT. The flex differs by a whopping 12 units, but they are very close overall. It's a wash in the middle, with the APDGT slighty more pop at the tip. Notice also the 3% spread btwn the Donnay X-Gold 99 and the 2013 PD. Near the center, they are very close, but near the tip, the much thicker beam of the PD is clearly superior up top, at an even lower sw. I'll leave that up to you to determine if these 1-3% difs are significant. I have no idea why The Donnay P1 has higher digits than it should near the tip, perhaps the hoop is stiffer than the flex point in the throat.

    I can elaborate if time permits. In the meantime you could have a look at Links 2, 5 for more on your power drop off question, and links 10 and 11 for the question about maximum power location.

    Hope that helps!

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    References, Links, Suggested Reading:

    Link [1] Basic Facts about Frames and Strings,
    The United States Racquet Stringers Association
    http://www.racquettech.com/top/basic_facts.html
    http://www.tennis-warehouse.com/lc/basicfacts.html

    Link [2] Raw Racquet Power, By Rod Cross
    http://www.racquetsportsindustry.com/articles/2006/02/raw_racquet_power.html

    Link [3] Racquet Handle Weighting And Maneuverablility, by Rod Cross
    http://www.racquetsportsindustry.com/articles/2006/04/racquet_handle_weighting_and_m.html

    Link [4] The Inch That Changed Tennis Forever, By Rod Cross
    http://www.racquetsportsindustry.com/articles/2006/01/the_inch_that_changed_tennis_f.html

    Link [5] Racquet Power Comparison Tool
    http://twu.tennis-warehouse.com/cgi-bin/comparepower.cgi

    Link [6] The Physics And Technology Of Tennis
    http://www.tennis-warehouse.com/The_Physics_and_Technology_of_Tennis/descpage-PHYSICS.html

    Link [7] Mark Philippoussis Service Speed Testing:
    Averages 124 MPH with a Wood Racquet, and 126 with his Graphite Racquet,
    Time Magazine, June 2009
    http://www.time.com/time/magazine/article/0,9171,1899876,00.html

    Link [8] Power Potential, The Total Performance Measurement
    http://twu.tennis-warehouse.com/learning_center/totalperformance.php

    Link [9] The Ingredients Of Maximum Shot Speed
    http://twu.tennis-warehouse.com/learning_center/maxspeedeasy.php

    Link [10] Maximum Shot Speed, Where to Hit on the Racquet
    http://twu.tennis-warehouse.com/learning_center/maxshotspeed.php

    Link [11] Why Is Maximum Power In the Throat and Maximum Shot Speed Toward The Tip?
    http://twu.tennis-warehouse.com/learning_center/PPandspeed.php

    Link [12] Compare Racquet Shot Speeds (Mph)
    http://twu.tennis-warehouse.com/cgi-bin/comparespeed.cgi

    Link [13] Compare Racquet Trajectories
    http://twu.tennis-warehouse.com/cgi-bin/trajectory_compare.cgi

    Link [14] More Tennis Physics, Rod Cross
    http://www.physics.usyd.edu.au/~cross/presentations.html

    Link [15] Power, Does the Racquet Matter?
    http://twu.tennis-warehouse.com/learning_center/racquetcontribution.php

    Link [16] Power Potential Test Procedure
    http://twu.tennis-warehouse.com/learning_center/test_method.php
     
    Last edited: Sep 25, 2013
    #24

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