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Frank Silbermann
10-23-2007, 07:07 PM
What are the bio-mechanical principles that cause a "control" or "players'" racket to offer more control than a power racket? How does greater flexibility translate into greater accuracy?

Is it because a too powerful racket forces a strong player to hold back, so that the variety of depth and power must be matched to a smaller range of effort -- thus making the differences in stroking speed more subtle?

Or is it that all rackets are dead around the perimeter, and therefore the livelier it is at its sweet spot the bigger a difference you get for each inch away from it?

Or is it string deformation that causes a loss of directional control, and if your strings aren't going to give then you need more give in the racket to avoid destroying your elbow?

Noveson
10-23-2007, 07:38 PM
What are the bio-mechanical principles that cause a "control" or "players'" racket to offer more control than a power racket? How does greater flexibility translate into greater accuracy?

Is it because a too powerful racket forces a strong player to hold back, so that the variety of depth and power must be matched to a smaller range of effort -- thus making the differences in stroking speed more subtle?

Or is it that all rackets are dead around the perimeter, and therefore the livelier it is at its sweet spot the bigger a difference you get for each inch away from it?

Or is it string deformation that causes a loss of directional control, and if your strings aren't going to give then you need more give in the racket to avoid destroying your elbow?

It doesn't. Quite the opposite in fact, that's why I love listening about the PS85's 'legendary' control. Stiffer racquets offer greater directional control, with all else being the same.

NoBadMojo
10-23-2007, 08:39 PM
What are the bio-mechanical principles that cause a "control" or "players'" racket to offer more control than a power racket? How does greater flexibility translate into greater accuracy?

?

It's because flexible racquets are less powerful racquets and people equate less power with more control.

for better players the control comes from spin control in large part, and better players can play well with just about anything and they indeed play with all manner of gear including 'game improvement' frames

the other element to the control subject is that denser stringbeds are usually less powerful stringbeds and therefore more controllable

people often overlook what arguably is the more important type of control....that being depth control. you gotta hit the sweetspot consistently for that kind of control, have good spin control, and have good technique and not let the ball get behind you...to that end, the larger headed lighter stiffer frame can actually be the easier racquet to control...................not the other way around

gerikoh
10-23-2007, 08:41 PM
flexible, stiffer stringbed, larger sweetspot, very stable, loads of headlight.
i'm not sure about the composition but wilson would usually defy the laws of physics.

Keifers
10-23-2007, 10:58 PM
The way I see it, more flex (and weight) in the frame means more ability to absorb the energy of a fast/heavy incoming ball, and the increased dwell time provided by the flex means more ability to control the direction and spin of the outgoing ball. At least that's the case with my game...

AlpineCadet
10-24-2007, 01:43 AM
What are the bio-mechanical principles that cause a "control" or "players'" racket to offer more control than a power racket? How does greater flexibility translate into greater accuracy?

Is it because a too powerful racket forces a strong player to hold back, so that the variety of depth and power must be matched to a smaller range of effort -- thus making the differences in stroking speed more subtle?

Or is it that all rackets are dead around the perimeter, and therefore the livelier it is at its sweet spot the bigger a difference you get for each inch away from it?

Or is it string deformation that causes a loss of directional control, and if your strings aren't going to give then you need more give in the racket to avoid destroying your elbow?

It doesn't. Quite the opposite in fact, that's why I love listening about the PS85's 'legendary' control. Stiffer racquets offer greater directional control, with all else being the same.

It's because flexible racquets are less powerful racquets and people equate less power with more control.

for better players the control comes from spin control in large part, and better players can play well with just about anything and they indeed play with all manner of gear including 'game improvement' frames

the other element to the control subject is that denser stringbeds are usually less powerful stringbeds and therefore more controllable

people often overlook what arguably is the more important type of control....that being depth control. you gotta hit the sweetspot consistently for that kind of control, have good spin control, and have good technique and not let the ball get behind you...to that end, the larger headed lighter stiffer frame can actually be the easier racquet to control...................not the other way around

flexible, stiffer stringbed, larger sweetspot, very stable, loads of headlight.
i'm not sure about the composition but wilson would usually defy the laws of physics.

The way I see it, more flex (and weight) in the frame means more ability to absorb the energy of a fast/heavy incoming ball, and the increased dwell time provided by the flex means more ability to control the direction and spin of the outgoing ball. At least that's the case with my game...

The answer is: it's subjective. Both can work the same for different players.

For some, a stiffer racket will give you better directional control, while for others, a softer racket will give you better directional control because of the user specific dwell time (which is needed for the individual to have the best control for their playing style.)

Hopefully this helps.

keithchircop
10-24-2007, 02:19 AM
What some people fail to understand is that not everyone HITS the same way and on the same surface. Some hit with heavy topspin, some hit with less topspin, some hit with no topspin at all. Some hit very hard, some hit moderately hard, some hit very soft. We are blessed to have such a huge variety of racquets to suit our particular playing styles.

The word "control" doesn't make any sense used this way. Nadal hits very hard with massive topspin with a midplus. Does he have control issues? Safin hits very hard with much, much less topspin using a midsize. Does he have control issues? Both their racquets suit their own games, especially on their favourite surfaces.

AlpineCadet
10-24-2007, 02:22 AM
Keith, are you jumping on that same bandwagon/train-of-thought after reading my post? Awesome! (Ignore me, I'm just patting myself on the back.)

keithchircop
10-24-2007, 02:36 AM
Keith, are you jumping on that same bandwagon/train-of-thought after reading my post? Awesome! (Ignore me, I'm just patting myself on the back.)

Whatever turns you on.

Seriously now, I'm glad you used the word "subjective". It seems few people around here grasp the concept of subjectivity.

Some people are like, "Get a BMW 750, it's the best car ever!".
Maybe you live in the Desert.
Maybe it's not available in left-hand-drive, which is what you're used to.
Maybe it's only available with manual gearshift, which you hate.
Maybe you don't have a garage, and you live in a bad Detroit neighborhood.
The BMW may well be a great car, just not a great car for you and your situation.

Player A plays on clay, B on hardcourts, C on grass.
A hits with heavy topspin, B with moderate topspin, C hits flat.
Offering the same advice to all of them is downright ridiculous. They control the ball in different ways because, that's right, they are different people in different situations. Hence, they should use different "control" racquets.

AlpineCadet
10-24-2007, 02:50 AM
Yeah, you did jump on that 'bandwagon.'

Nice!


*pats himself on the back*

keithchircop
10-24-2007, 03:05 AM
Yeah, you did jump on that 'bandwagon.'

Nice!

*pats himself on the back*

Am I on the bandwagon?

Now, the world don't move to the beat of just one drum,
What might be right for you, may not be right for some.
A man is born, he's a man of means.
Then along come two, they got nothing but their jeans.
But they got, Diff'rent Strokes.
It takes, Diff'rent Strokes.
It takes, Diff'rent Strokes to move the world.
Everybody's got a special kind of story
Everybody finds a way to shine,
It don't matter that you got not alot
So what,
They'll have theirs, and you'll have yours, and I'll have mine.
And together we'll be fine....
Because it takes, Diff'rent Strokes to move the world.
Yes it does.
It takes, Diff'rent Strokes to move the world.

Damn right I am.

AlpineCadet
10-24-2007, 03:10 AM
What an awesome thread. (I wish more threads were like this one.)

keithchircop
10-24-2007, 03:28 AM
Yeah, we totally hijacked a thread about bio-mechanical principles of physics, and string deformation causing loss of directional control.

I guess it was my way of telling the OP: "Dude, I don't know."

paulfreda
10-24-2007, 04:33 AM
Great question Frank !

Note that this discussion could be taking place in 1965 or earlier as this is a classic issue in tennis technique .... control vs power.
The parameter of spin which came about with Borg and his use of topspin; and the equipment revolution beginning with Howard Head using alternative materials have changed the game and has raised the level of play enormously.
So topspin with a
lighter [fast swing],
stiffer [more power],
modern frame brings new dimensions and thus meaning to the word control.

That being said ..............

What are the bio-mechanical principles that cause a "control" or "players'" racket to offer more control than a power racket? How does greater flexibility translate into greater accuracy?

Flexibility in a frame allows it to absorb the kinetic energy of the ball. Thus the player must supply more power to return the ball. This puts the player "in control" because it is he and not the frame which determines power/pace.
Note that this is depth control which is the classic and most fundamental type of control. To be able to hit deep keeping the opponent behind the baseline puts him on defense, takes time away from him and cuts down on his angles.


Is it because a too powerful racket forces a strong player to hold back, so that the variety of depth and power must be matched to a smaller range of effort -- thus making the differences in stroking speed more subtle ?
Yes !


Or is it that all rackets are dead around the perimeter, and therefore the livelier it is at its sweet spot the bigger a difference you get for each inch away from it ?
Now we are talking directional control. Lower tensions yield less directional control most would agree. And stiffer frames increase directional control.


Or is it string deformation that causes a loss of directional control, and if your strings aren't going to give then you need more give in the racket to avoid destroying your elbow?
I would agree that high tensions can hurt an elbow on any frame, but less so with a flexible frame.
I personally had a terrible TE problem 6 years ago with a flexible heavy frame and it was not until I dropped tension to below 50 that it went away. I am back to 52-54 these days but only with frames with stiffness at or under 65.

Frank Silbermann
10-24-2007, 08:55 PM
Great question Frank !

Flexibility in a frame allows it to absorb the kinetic energy of the ball. Thus the player must supply more power to return the ball. This puts the player "in control" because it is he and not the frame which determines power/pace.
Note that this is depth control which is the classic and most fundamental type of control.

Lower tensions yield less directional control most would agree. And stiffer frames increase directional control.
Then it would seem to me that the ideal racket has a staff which is very flexible right above the grip, with gradually increasing stiffness towards the tip (so the racket gives without being dead at the top). It would be even better if the flexibility were in a single dimension, i.e., that the staff could bend straight back but couldn't twist.

Ideally, this should be accomplished through high tech materials, rather than using a wide-body strategy (a wide beam prevents heavy topspin).

Has any racket manufacturer tried to do this sort of thing?

paulfreda
10-24-2007, 09:16 PM
Then it would seem to me that the ideal racket has a staff which is very flexible right above the grip, with gradually increasing stiffness towards the tip (so the racket gives without being dead at the top). It would be even better if the flexibility were in a single dimension, i.e., that the staff could bend straight back but couldn't twist.

Ideally, this should be accomplished through high tech materials, rather than using a wide-body strategy (a wide beam prevents heavy topspin).

Has any racket manufacturer tried to do this sort of thing?

I don't know the answer to that question.

But you raise an important issue and that is specification details.
Present specs do not tell us enough about what the variations in weight/density along the frame [weight/density distribution] , stiffness along the frame [stiffness distribution; altho some frames say 22m then 23mm, etc if thickness varies], and stiffness versus x, y z direction are.
This is important for things like swingweight. Two frames can have the same SW and balance but very different weight distibutions.
Some players would like to know this information.
Especially those who customize their frames.

ps60
10-24-2007, 10:45 PM
i love the feel of soft rackets, but they are not quite stable.

n90,K90 or some darn stiff Prince (tweeners) are stable, but i don't really like the feedback.

Strings (again) plays a major part in control i think. Just 2 lb. lighter in the mains (same PSGD) on my T10 mid makes it an unbearable rocker launcher !

Azrael
10-25-2007, 12:55 PM
...bio mechanical?

And to join the bandwagon, I agree with keithchircop and AlpineCadet.

Legend of Borg
10-25-2007, 01:15 PM
It doesn't. Quite the opposite in fact, that's why I love listening about the PS85's 'legendary' control. Stiffer racquets offer greater directional control, with all else being the same.

So, let me get this straight. Stiffer rackets offer more accuracy at the cost of power and vice versa?

AlpineCadet
10-25-2007, 01:22 PM
So, let me get this straight. Stiffer rackets offer more accuracy at the cost of power and vice versa?

Did you read through the entire thread? lol. In my words, you can increase your control of the ball with either a stiffer OR softer frame because it's subjective and depends on your playing style and personal preferences.

Klatu Verata Necktie
10-25-2007, 06:49 PM
So, let me get this straight. Stiffer rackets offer more accuracy at the cost of power and vice versa?

I think it is generally accepted that, all things being equal, a stiffer racquet will be more powerful than a more flexible racquet.

Cervantes
10-25-2007, 10:16 PM
You're right...It all depends on your personal appearance...


"Iím the knot in the pit of your stomach..."
George W.

keithchircop
10-25-2007, 10:47 PM
And to join the bandwagon, I agree with keithchircop and AlpineCadet.

Welcome to the bandwagon!

AlpineCadet
10-25-2007, 11:59 PM
My bandwagon. I have been the first to say this: do a search. :D


*chuckles*

marcb
10-31-2007, 03:36 PM
This is a fantastic (albiet slightly old) resource for the physics behind racquet science. Polish your slide rule and happy reading.

http://www.racquetresearch.com/sevencri.htm