The Women's Modern Forehand

[mntlblok]

Left arm

Going back to the top, those clips are high speed with more frames.

Here's a hint. What is the role of the left arm in all three?

I spent a bit of time checking that out and I've spent a fair bit of time pondering your screen shots of all the men together looking almost identical with their left arms pointing to the side at the end of their full turns - even to the point of most having their *fingers* spread in practically the same manner.

It initially really bugged me that over the years almost nobody had ever emphasized that position, or even the unit turn, to me. During the past year (since following TennisPlayer), whenever I've watched good players and then had a chance to pester them about it, I've asked who taught them to do that with their left arms (they've all done it, at least to some degree). Not only have none of them been able to tell me how they learned it, they don't seem to even be aware that they do it.

So, that makes me wonder if this is just another "result", rather than a cause, in the modern forehand. I looked to see in the clips if they were all using the left arm to hold onto the frame for changing their grips, but Justine finishes her grip change before the shoulder turn.

I've wondered if the left arm gets to that "pointing to the side" position due to having been left holding the frame for as long as possible so as to force a shoulder turn, but some of the pros let go of it pretty early. (My theory is that this might be the *best* reason for getting it over there).

I *think* I've noticed that Lindsay both takes her racket back further and points her left arm *less* sideways than others. Roger (and Agassi) seem to take the racket back the least and seem to have the more extreme pointing of the left arm - even *past* sideways.

So, I'm now wondering if the primary purpose of the pointing of the left arm is to control the amount of counterbalance that is necessary for the type of backswing. It sort of reminds me of what you've pointed out with the opposite arm in the most recent one handed backhand article - the more the swing tends to send one off balance, the more the opposite arm swings in the opposite direction (see Lindsay).

I think I've read that the pointing of the left arm is done in order to make the shoulders turn more in the forehand "backswing". While I am sure that this is so to some degree, I can certainly rotate my shoulders plenty without doing *anything* with my left arm. But, with a racket in my hand, I think I would have a more difficult time getting my weight going in the direction I wanted if I didn't extend my left arm some.

I've also noticed that not all players keep the left arm *straight* when they point it to the side (see Justine's move). I would think that the straighter it is kept, the better it would act as a counterbalance.

Now, tell us what the *real* answer is.

Kevin
Savannah

[BrianGordon]

left arm

Happy New Year-

The real answer is - the role of the non-hitting arm on a one handed swing is one or more of the following:

1. An aid to preparation.

2. A direct aid to the driving leg(s) in generating force against the ground (the source of body rotation) - this occurs when the arm is swung in the direction of rotation - the arm swing causes an opposite rotation of the rest of the body which helps the leg(s) push - Newtons 3rd Law.

3. To regulate body rotation speed - for simplicity we can say that arm positional manipulation either increases or decreases the body's moment of inertia (reluctance to rotate) which in turn decreases or increases body rotation speed respectively about an axis in question.

It is that simple, true for all one handed strokes, gender independent, and is an auto-response(2&3) given the global goal of increasing or slowing rotation (i.e. it does not have to coached but probably should be).

[johnyandell]

Kevin,

Just because a player can't describe it doesn't mean that what he does is a consequence. I wouldn't be looking for players to ever be a reliable source of info on this or any technical subject. They play naturally from the inside out versus the rest of us who try to analyze and then try to implement this info from the outside in.

Pete Sampras once told a coach I know "I don't know how to volley." He had been asked to explain the volley to a group of young players. What this probably meant was he had no idea how to explain it in words. It certainly didn't mean that he didn't execute the key motions perfectly in perfect sequence.

Brian,

Judicious, compelling and factual as usual. Wonder if you agree that the left arm increases the amount of turn and the loading or coiling (please correct terminology if necessary) in the upper body. The harder fuller turn with that left arm seems to generate more natural pace with most of the players I've worked with and I've seen dramatic changes with a little more stretch from high school girls to D1 college players, to satellite and lower level tour guys.

Thoughts?

[mntlblok]

Kevin,

Pete Sampras once told a coach I know "I don't know how to volley." He had been asked to explain the volley to a group of young players. What this probably meant was he had no idea how to explain it in words. It certainly didn't mean that he didn't execute the key motions perfectly in perfect sequence.

Well, that just boggles my mind, then. How the heck did he ever learn to do it? Surely he didn't walk out and volley great from day one, did he? If not, then did he just learn it from trial and error, or did he learn it from instruction? Either way, it looks like he would have had to have thought it through at *some* level.

I certainly understand that these super athletes have something that we don't, but surely they don't have great strokes just magically appear, do they? I've never seen or been around anyone who went from being a beginner to becoming a top player, so I really don't have any idea what that must be like. It would be fascinating to know.

Specifically, though, on this left arm thing, are you saying that it is such a necessary move in order to hit a good, modern forehand that all good players must necessarily end up doing it? My somewhat limited experience is that teaching pros don't generally include it as part of their instruction for hitting a forehand. What percentage of teaching pros would you say teach it? Have you ever had to teach it to "already good" players?

I can see that it doesn't necessarily follow that it would be a "consequence" just because players don't know that they're doing it, but it still kind of blows me away how universal it seems to be among very good players, yet it seems not to be univerally taught. Maybe holding onto the racket with the left hand and sort of pushing the racket back as part of the turn *is* universally taught (though I don't remember hearing it in any instruction I've had), and that seems to pretty well get the left arm headed to that position. I *do* see that a good forehand isn't likely to happen without a good unit turn.

Thanks for taking the time to straighten me out - both you *and* Brian.

Kevin
Savannah

[johnyandell]

Do you honestly think Michael Jordan learned his jump shot in a step by step progression from a basketball teaching pro?

I'm sure Pete heard a lot of things when he was learning--see the great Peter Smith article on the Two Step Volley. That doesn't mean he processed it like he was in dental school. There wasn't a written exam.

It shows how much you are in your head about the whole thing. Honestly it is just plain painful to read your posts. Good players watch other good players, they assimilate, they experiment, they feel. They don't have preconceptions that block them from feeling the results.

When they get stuck they usualy just need a picture or two or ten. That usually gets them back to the feel. They mostly could care less about unified theory of stroke production. It's a necessary process--but the idea is to hit the ball well not understand how to hit the ball well. I don't think you get that.

[BrianGordon]

Wonder if you agree that the left arm increases the amount of turn and the loading or coiling (please correct terminology if necessary) in the upper body. The harder fuller turn with that left arm seems to generate more natural pace with most of the players I've worked with and I've seen dramatic changes with a little more stretch from high school girls to D1 college players, to satellite and lower level tour guys.

Thoughts?

John-

YES! - if executed correctly you are EXACTLY correct - both in preparation (amount, and loading) and forward swing execution (magnitude via improved muscle contractile conditions - and probably coiling depending on what that means) - particulary in preparation I key the entire motion off non-hitting arm action (think this through as I know you always do) - and while the forward swing execution will occur naturally, it can be greatly enhanced with proper coaching - touche!

[ccrood]

left arm

[FONT=Arial]

The left arm is simply used as a guide...a helper to set the swing pattern through the contact point. The key thing in teaching is....EVERY player is diff....they will have their own way to set up the proper left arm participation in the process...but the pro's job is to find the best use for their style.

[johnyandell]

I do try to think things thru... To me this is one of the few consistent factors across all the players and grip styles on virtually every ball. At least in the men.

There are some variations in the height of the arm and how long the left arm stays on the racket before straightening out. But with very few exceptions in the men, it stretches across parallel to the baseline.

Now the interesting question is why this is different in the women. That's the main difference in the high speed footage at the top of this thread that I see between Lindsay--who is fairly typical with the left arm for a women--versus Roger.

Justine on the other hand has modeled her revised forehand after the men--especially Agassi--she stretches the left arm out a lot straighter and quite a bit further.

[cyberhound]

Left Hand

Boy that left hand thing killed this thread dead!!

So FWIW here's my take on it. I think the that men's forehands with SSC , racquet staying in front of the body, and low finish are more purely rotational than the women's forehand's with racquet and wrist behind the body, no SSC and finish over the shoulder. The women's swing tends to try to more linear. The do rotate some, but the swing style tends to use linear power and vertical lift probably from the biceps. It's easier to generate rotational energy with the arm back. When I've seen Federer play in person and he really drives the ball, he looks like a top spinning in one spot.

The second issue is balance and how to start the swing. With the arm and racquet pulled behind the body it just feels awkward and unbalanced to pull the left arm back. ( At least for me anyway).

The third factor is starting the swing. With the rotational SSC swing, the hips open aided by the left arm coming forward to start the rotation. With the women's attempt at a more linear power generation, the swing is started by pulling the left arm back toward the body from the extended to the front postion. This helps start the right arm forward and keeps the shoulders from opening quite so much until the follow through.

Hope this generates some controversy to get this thread restarted.

[BrianGordon]

Cyberhound-

Perhaps your comments would spark debate or controversy if someone could figure out their meaning (at least I can’t). With all due respect I can’t find a single point that meshes with my understanding of stroke mechanics. Perhaps you could elaborate on some items:

1 – Female strokes are more linear. The example you site is the biceps, yet the biceps causes ROTATION of the elbow which is LINKED to linear motion of the racquet face. All strokes by all people are ultimately rotational by definition. The only linear component is that of the body center of mass which is relatively insignificant and not differentiated by gender.

2 – SSC utilization and a “rotational SSC swing” – no clue, please enlighten us. Since we see this acronym tossed about of late, I wonder how you apply it in your explanation. The SSC requires stretching of a given muscle in ECCENTRIC (trying to shorten) conditions followed immediately by a CONCENTRIC (actually shortening) action. IF this occurs then:

----There may be neural enhancement to the concentric phase through the stretch-reflex mechanism.

-----There may be passive enhancement to the concentric phase from elastic energy released from stretched components such as tendons.

-----And there is a time to maximum force benefit implied through the pretension of the muscle stretched in the eccentric phase.

How do you determine these actions occur at all, in which muscles, and how is it that men use it and women don’t.

3 – How the actions of the left arm work as you say and what you mean by kinetic energy – what form, what part of the body, how generation is enhanced by various segmental configurations, and why this is important to shot outcome.

I don’t intend this as mean spirited, but your post illustrates a trend in the Tennis world to use mechanical terminology to analyze technique without the requisite expanation.

[cyberhound]

left hand

From Brian Gordon post interspersed with my comments.


"The example you site is the biceps, yet the biceps causes ROTATION of the elbow which is LINKED to linear motion of the racquet face. All strokes by all people are ultimately rotational by definition. The only linear component is that of the body center of mass which is relatively insignificant and not differentiated by gender."

I said perhaps using biceps contraction I didn't cite it as an example. Anyway it's a side issue that distracts from the main point. When I started to play a long time ago I used Vic Braden's "Tennis for the future" as a referenc. He espoused keeping the racquet on the side of the body facing the side fence both on the backswing and of the finish. On the backswing don't go farther past the plane of the shoulders, on the finish arm pointed at the sky and directly in front of the right shoulder. The swing was to be accoplished by lifting with the legs uncoiling the hips but trying to stop that motion when the navel was looking at the ball. (his third eye concept). The palm was supposed to stay directly along the flight path of the ball and the arm didn't pronate. You step into the ball and transfer the weight from right foot to left foot. Perhaps the closest example of this today is the running or off the back foot forehand where one can't get the body into the shot and the the finish is to the right side of the body ( Lansdorp's reverse forehand). To me that seems like an attempt to make all the force generation actions as linear as possible. That contrasts to say federer's swing with 180 degrees of shoulder rotation, arm pronation, uses rotational force generation actions.

"2 – SSC utilization and a “rotational SSC swing” – no clue, please enlighten us."

The SSC refers to stretch-shortening cycle and all that that means. In this instance for lack of better label I used it as a label to refer to the Federer type of swing the racquet kept on the front side of the body and the supination/pronation cycle started at the bottom of the downswing. The label was intended to be a short term to refer to this type of swing rather than the type of swing where the wrist is layed back and pre-stretch and the racquet taken behind the back as the women are more apt to do.

"The SSC requires stretching of a given muscle in ECCENTRIC (trying to shorten) conditions followed immediately by a CONCENTRIC (actually shortening) action. IF this occurs then:

----There may be ... mechanism.

-----There may be passive ...tendons.

-----And there ...phase."

Since this is an label and I'm not discussing the way the SSC occurs all this techical mumbo-jumbo is an inapplicalble red herring .

"How do you determine these actions occur at all, in which muscles, and how is it that men use it and women don’t."

From the video's it appears that the supination/pronation occurs in the Federer and Henin videos and not in the Davenport video as her wrist is layed back on the backswing. I believe that you have previously said that if the muscles are are already stretched that the reflex contraction won't happen. If I were refering to any it would be the forearm. There may well be chest, thigh and other SSC's at work but they are also irrelevant. I was attempting to talk about the action of the left arm when pointed at the opponent or ball rather than when parallel to the base line. Sorry for any confusion.

"3 – How the actions of the left arm work as you say and what you mean by kinetic energy – what form, what part of the body, how generation is enhanced by various segmental configurations, and why this is important to shot outcome."

I'm not even sure what you mean by this

"I don’t intend this as mean spirited, but your post illustrates a trend in the Tennis world to use mechanical terminology to analyze technique without the requisite expanation."

Maybe it wasn't mean spirited, but to sensitive thin skinned guy, all of this speaking in obscure multiple combinations of technical terms, Latin when English would have worked; seems the exemplar inclulcating paradigms attempting to befuddle and intimidate.

respectfully,
cyberhound

[BrianGordon]

Cyberhound-

Thanks for the clarification - your intended meaning is much more clear with this expansion of thoughts - we'll have to disagree on linear/angular, SSC as a generic term to describe a type of stroke, use of the SSC in general, inherent gender differences in use of the non-hitting arm, Latin/English, and befuddle/intimidate - but I do appreciate your effort in the elaboration on your earlier comments - keep up the good work in "generating controversy".

[cyberhound]

controversy

Cyberhound-

Thanks for the clarification - your intended meaning is much more clear with this expansion of thoughts - we'll have to disagree on linear/angular, SSC as a generic term to describe a type of stroke, use of the SSC in general, inherent gender differences in use of the non-hitting arm, Latin/English, and befuddle/intimidate - but I do appreciate your effort in the elaboration on your earlier comments - keep up the good work in "generating controversy".

I don't think I said there was any inherent gender differences. I beleive jyandell made the comment that the arm out front was mostly used by women and the arm parallel to the baseline was used more by men. I think the only inherent gender differences are anatomical and hormonal.

Regarding linear/angular SSC as a label, if you have a better one I'm game. Describing it in detail every time wastes a lot of bandwidth.

Regarding linear, if you pick up "Tennis for the future", you can read where Vic Braden says that rotation on the swing is bad--pulls the ball off target horizantally and you can't hit down the line. The palm and arm must stay in line with the intended flight path of the ball. All force should be lifting up or moving along the flight path. All backed up Biomechanical research and high speed filming. Although I guess it is all rotational, just different axis a horizantal axis instead of vertical axis. The old bowling ball swing.

When I learned I could swing a lot more horizontally, finish down by the hip and rotate my shoulders 180 degrees and still hit the target and use a semi open stance instead of a totally square stance, it made a heck of a difference.

Thanks the compliment about controversy, but I meant controversy about the use of the left arm rather than grammar and semantics.

[BrianGordon]

Cyberhound-

Congratulations, it looks like that thin skin just thickened. Your final comment implies the previous discussion was mostly a disagreement about terminology – wrong, it was a discussion about fact versus fiction. It is clear that you are unwilling to consider the complex and important process details that determine the stroke production you see on video. Instead, you dismiss them as mumbo jumbo and a waste of bandwidth. Fair enough, but it certainly makes further discussion a waste of time. I suspect our differing perspectives on detail reflect diversity in goals – mine is to understand every aspect of stroke mechanics – yours seems to be to hit a better forehand. I guess the readership will have to separate the wheat from the chaff in this discussion.

[johnyandell]

Cyberhound,

No one is trying to imtimidate anyone. You have to admit you have been a master of terminology use in these threads!

I think that it is fantastic that we have someone with Brian's background--and there may be no one else with his combo skill sets on the planet--feeding us back.

I myself have been unwilling to use terms like SSC casually and am trying to learn from Brian.

This is a great comment on the linear/rotational distinction that I think everyone should note:

"All strokes by all people are ultimately rotational by definition. The only linear component is that of the body center of mass which is relatively insignificant and not differentiated by gender."

The left arm on the women and the timing of the torso rotation is definitely different. Should they hit more like the men? Can they? These are some of the issues I hoped this thread might address.

We'll have more on the gender differences later in an article from Anne Pankhurst.

John Yandell