Bent versus Straight Hitting Arms

[jeremy93]

Jeremy -

Here's Brian's article on different backswings.

https://www.tennisplayer.net/members/biomechanics/brian_gordon/understanding_professional_forehands/part_01/

To paraphrase Brian - The elbow is lifted in the backswing then drops the arm from the shoulder to get a more vertical hand path that carries speed into the forward swing.

Thanks Seano, I’ll have to look at that again. I read/watched it a while ago.

[arturohernandez]

Jeremy -

Here's Brian's article on different backswings.

https://www.tennisplayer.net/members/biomechanics/brian_gordon/understanding_professional_forehands/part_01/

To paraphrase Brian - The elbow is lifted in the backswing then drops the arm from the shoulder to get a more vertical hand path that carries speed into the forward swing.

Thanks for reminding us of this technical work. I have to keep rereading it and thinking about it on a fourth pass. I imagine that coaches who have played at the pro level and then coached at the pro level know a lot about tennis.

I suppose there are those who know a lot about biomechanics. Then there is the BG (the OG BG?). I consider myself lucky to have access to it.

To think that it all started with a book with still photographs of tennis strokes.

https://www.amazon.com/Visual-Tennis-2nd-John-Yandell/dp/0880118032

[seano]

Jeremy -

Here's Brian's article on different backswings.

https://www.tennisplayer.net/members/biomechanics/brian_gordon/understanding_professional_forehands/part_01/

To paraphrase Brian - The elbow is lifted in the backswing then drops the arm from the shoulder to get a more vertical hand path that carries speed into the forward swing.

[jeremy93]

I was doing alright with Pat Cash's descriptions of straight- and bent-arm forehands until I got to this:

"Because a bent arm forehand brings your contact point closer to your core which is a stronger, more balanced position. From here your body can twist, turn, tilt and adjust all at the same time without causing resistance in your kinetic chain. The result is a fluid, relaxed and stable forehand stroke that is less injury prone."

It is not obvious why having the contact point closer to your core is more powerful than the extra leverage you get with a straight-arm forehand. Maybe you can rotate faster the closer the contact point is to you, like ice skaters pulling their arms in to spin faster, but then there's that extra leverage the farther away from you the contact point is. It is also not obvious why having a closer contact point is more balanced; try standing on one foot, eyes closed, with your arms folded and then outstretched.

The kinetic chain for a forehand, as for backhands and, especially, serves, consists of a sequence of accelerations, then decelerations, of each part of the body, always starting with the legs and ending with the head of the racket. In the process, the kinetic eneragy of each part is concentrated into a smaller mass, thereby increasing the velocity of the increasingly smaller mass. So, these strokes are all whip cracks. With a whip, all of that kinetic energy ends up in the tip, which breaks the sound barrier (~800 mph) producing the "crack."

If that's the kinetic chain, I'm not sure what "resistance in the kinetic chain" means. It looks like players hit forehands by rotating, then briefly decelerating, their hitting shoulder (relative to their upper arm), just like cracking a whip. The momentum of the arm and racket then drags the shoulder around, giving the illusion that the shoulder is powering through the shot. I'm not sure about this, but if you look closely at the relative speed of the hitting shoulder and upper arm, there's a big change just before or at the instant of impact. Also, when I try to momentarily stop my shoulder rotation just before contact, the ball goes faster, but, then, I'm not Roger or Rafa. Anyway, I don't see where there would be any more "resistance," which I asume means "disruption" of the kinetic chain with a straight, compared to a bent, arm.

As a practical mater, for all of us normal humans, with the footwork of alligators, we're hitting any forehand we can reach, sometimes with a 90 degree, rib-bruising, bent arm to a desperately straight one when we're stretched out. And the way tour level players are hitting groundstroke angles, it seems like they would be doing the same when they have to, for example, Medvedev.

Great points in everything here. As BG said, the straight arm seems to be more common with the younger players atp and wta then in the past. Not a huge fan of the article for some of the reasons you mentioned. Happy to see a successful tennis player try to make it in the teaching world however.

[jeremy93]

Good discussion folks. And though I don't like (or have the time) to interfere in threads outside of my articles, I guess this one hits close to home.

I agree, and have said many times, the straight arm is very difficult to hit and is probably not a great solution for the vast majority of players. On the other hand, the degree of bend is variable and I think this is lost in the article (and examples).

Elbow angles in excess of 150 or 160 mimic the straight arm mechanics much more than they do the more bent counterparts. The mechanics logic in this article, such as it is, could only apply to very bent elbows though I question (as others have) the injury differences and I have no idea what "resistance in your kinetic chain" even means.

Over the years I've discussed many attributes of straight or nearly straight hitting arm structures. It is my position that adding a degree of freedom (the shoulder joint) enhances the ability to produce horizontal AND vertical racquet speed in relative isolation (though not unrelated).

Sean has done a great job of summarizing my logic in the horizontal direction. Perhaps more important is the straight arm benefit to producing vertical speed from the slot dynamics and superior ISR configuration.

And so... while I respect what Mr. Cash did on the court and his opinion on this issue, I stand by my long developed interpretation. Ultimately the athletes will resolve this one I guess. Anecdotally it seems to me elbows are getting more, not less, straight for the up-and-comers at the high performance level, and on both tours - and for good reason. Stay tuned.

Thanks a lot for the knowledgeable words Brian

[jeremy93]

In re-watching - Brian's video in Understanding Professional Forehands Part 1 (10:42 minutes in length) - He discusses 3 reasons why the straight arm is better than a bent arm in creating hand speed the forward swing.

1) Because the arm/racquet are further away from the shoulder joint in the backswing, it creates more LAG in the early part of the forward swing and puts the muscles more on stretch.
2) More inertial effect swinging forward because the arm/racquet are further away from the shoulder, causing the muscle fibers to contract at a slower rate, creating more force.
3) Speed of the hand is proportional to the angular velocity of the shoulder joint X the distance from the shoulder to the hand (his words, not mine). With the straight arm, the distance is greater between shoulder and the hand, creating much more hand speed.

This is why bent arm forehands tend to have a functional backswing, in order to make up the difference from the starting point to the contact point. They need to carry hand speed into the starting point.

Also the bent elbow is less likely to have independent arm motion. Remember the ideal is to have the arm spring through the torso rotation with minimal muscular activity.

I sometimes enjoy getting into the weeds of the strokes to fully appreciate what is actually happening.

Sean

Seano could you expand on the below words? What do you mean by functional backswing? Thanks in advance.

“This is why bent arm forehands tend to have a functional backswing, in order to make up the difference from the starting point to the contact point. They need to carry hand speed into the starting point.”

[jeremy93]

One interesting thing about the article is the idea of moving the body in synchrony. My daughter would practice a modified forehand while holding her hitting arm wrist with her left hand. We also do medicine ball throws. A lot of the mechanics are similar to these two motions and she hits with a bent arm. Her forehand is very good. She is compact so she can absorb power quite well.

Also, I wonder if Federer uses more of a bent arm for returns and for some of his forehands that have more feel.

https://www.tennisplayer.net/members...act_classical/

I’m confident Fed uses a bit of a bent arm when returning and when hitting angles (feel shots).

[bjmiller]

I was doing alright with Pat Cash's descriptions of straight- and bent-arm forehands until I got to this:

"Because a bent arm forehand brings your contact point closer to your core which is a stronger, more balanced position. From here your body can twist, turn, tilt and adjust all at the same time without causing resistance in your kinetic chain. The result is a fluid, relaxed and stable forehand stroke that is less injury prone."

It is not obvious why having the contact point closer to your core is more powerful than the extra leverage you get with a straight-arm forehand. Maybe you can rotate faster the closer the contact point is to you, like ice skaters pulling their arms in to spin faster, but then there's that extra leverage the farther away from you the contact point is. It is also not obvious why having a closer contact point is more balanced; try standing on one foot, eyes closed, with your arms folded and then outstretched.

The kinetic chain for a forehand, as for backhands and, especially, serves, consists of a sequence of accelerations, then decelerations, of each part of the body, always starting with the legs and ending with the head of the racket. In the process, the kinetic eneragy of each part is concentrated into a smaller mass, thereby increasing the velocity of the increasingly smaller mass. So, these strokes are all whip cracks. With a whip, all of that kinetic energy ends up in the tip, which breaks the sound barrier (~800 mph) producing the "crack."

If that's the kinetic chain, I'm not sure what "resistance in the kinetic chain" means. It looks like players hit forehands by rotating, then briefly decelerating, their hitting shoulder (relative to their upper arm), just like cracking a whip. The momentum of the arm and racket then drags the shoulder around, giving the illusion that the shoulder is powering through the shot. I'm not sure about this, but if you look closely at the relative speed of the hitting shoulder and upper arm, there's a big change just before or at the instant of impact. Also, when I try to momentarily stop my shoulder rotation just before contact, the ball goes faster, but, then, I'm not Roger or Rafa. Anyway, I don't see where there would be any more "resistance," which I asume means "disruption" of the kinetic chain with a straight, compared to a bent, arm.

As a practical mater, for all of us normal humans, with the footwork of alligators, we're hitting any forehand we can reach, sometimes with a 90 degree, rib-bruising, bent arm to a desperately straight one when we're stretched out. And the way tour level players are hitting groundstroke angles, it seems like they would be doing the same when they have to, for example, Medvedev.

[ten1050]

A number of years ago, I had a bad case of tennis elbow. My physical therapist recommended that I use a straight arm on my forehand since my forehand was causing all the problems. At the time, I thought the therapist was wrong however I gave it a try out of sheer desperation. My tennis elbow disappeared, my forehand improved, and best of all I could play tennis every day. There is a wonderful comment above that essentially states that a straight arm will move through the torso rotation with less muscular activity. Maybe the straight arm has contributed to Roger’s longevity.

Norman Ashbrooke

[arturohernandez]

In re-watching - Brian's video in Understanding Professional Forehands Part 1 (10:42 minutes in length) - He discusses 3 reasons why the straight arm is better than a bent arm in creating hand speed the forward swing.

1) Because the arm/racquet are further away from the shoulder joint in the backswing, it creates more LAG in the early part of the forward swing and puts the muscles more on stretch.
2) More inertial effect swinging forward because the arm/racquet are further away from the shoulder, causing the muscle fibers to contract at a slower rate, creating more force.
3) Speed of the hand is proportional to the angular velocity of the shoulder joint X the distance from the shoulder to the hand (his words, not mine). With the straight arm, the distance is greater between shoulder and the hand, creating much more hand speed.

This is why bent arm forehands tend to have a functional backswing, in order to make up the difference from the starting point to the contact point. They need to carry hand speed into the starting point.

Also the bent elbow is less likely to have independent arm motion. Remember the ideal is to have the arm spring through the torso rotation with minimal muscular activity.

I sometimes enjoy getting into the weeds of the strokes to fully appreciate what is actually happening.

Sean

Thanks for the summary. It is also why, at least for me, the reverse forehand gives the feeling more independent arm movement. As Brian pointed out this independent movement can be achieved with some bend. I have also experimented with holding the tip of the racket in the backswing and have my kids pull the racket forward.

The spring idea is great. There is a lot of racket head speed that can be created with this lag, spring and release.

[arturohernandez]

Good discussion folks. And though I don't like (or have the time) to interfere in threads outside of my articles, I guess this one hits close to home.

I agree, and have said many times, the straight arm is very difficult to hit and is probably not a great solution for the vast majority of players. On the other hand, the degree of bend is variable and I think this is lost in the article (and examples).

Elbow angles in excess of 150 or 160 mimic the straight arm mechanics much more than they do the more bent counterparts. The mechanics logic in this article, such as it is, could only apply to very bent elbows though I question (as others have) the injury differences and I have no idea what "resistance in your kinetic chain" even means.

Over the years I've discussed many attributes of straight or nearly straight hitting arm structures. It is my position that adding a degree of freedom (the shoulder joint) enhances the ability to produce horizontal AND vertical racquet speed in relative isolation (though not unrelated).

Sean has done a great job of summarizing my logic in the horizontal direction. Perhaps more important is the straight arm benefit to producing vertical speed from the slot dynamics and superior ISR configuration.

And so... while I respect what Mr. Cash did on the court and his opinion on this issue, I stand by my long developed interpretation. Ultimately the athletes will resolve this one I guess. Anecdotally it seems to me elbows are getting more, not less, straight for the up-and-comers at the high performance level, and on both tours - and for good reason. Stay tuned.

I knew it! Thanks for giving us your 2 cents. If I ever go back to school or training of any sort, I am going to book a ticket and hotel and just follow you around and pickup balls so that I can just listen and watch. The only problem her is that this is a big IF.

[BrianGordon]

Good discussion folks. And though I don't like (or have the time) to interfere in threads outside of my articles, I guess this one hits close to home.

I agree, and have said many times, the straight arm is very difficult to hit and is probably not a great solution for the vast majority of players. On the other hand, the degree of bend is variable and I think this is lost in the article (and examples).

Elbow angles in excess of 150 or 160 mimic the straight arm mechanics much more than they do the more bent counterparts. The mechanics logic in this article, such as it is, could only apply to very bent elbows though I question (as others have) the injury differences and I have no idea what "resistance in your kinetic chain" even means.

Over the years I've discussed many attributes of straight or nearly straight hitting arm structures. It is my position that adding a degree of freedom (the shoulder joint) enhances the ability to produce horizontal AND vertical racquet speed in relative isolation (though not unrelated).

Sean has done a great job of summarizing my logic in the horizontal direction. Perhaps more important is the straight arm benefit to producing vertical speed from the slot dynamics and superior ISR configuration.

And so... while I respect what Mr. Cash did on the court and his opinion on this issue, I stand by my long developed interpretation. Ultimately the athletes will resolve this one I guess. Anecdotally it seems to me elbows are getting more, not less, straight for the up-and-comers at the high performance level, and on both tours - and for good reason. Stay tuned.

[seano]

In re-watching - Brian's video in Understanding Professional Forehands Part 1 (10:42 minutes in length) - He discusses 3 reasons why the straight arm is better than a bent arm in creating hand speed the forward swing.

1) Because the arm/racquet are further away from the shoulder joint in the backswing, it creates more LAG in the early part of the forward swing and puts the muscles more on stretch.
2) More inertial effect swinging forward because the arm/racquet are further away from the shoulder, causing the muscle fibers to contract at a slower rate, creating more force.
3) Speed of the hand is proportional to the angular velocity of the shoulder joint X the distance from the shoulder to the hand (his words, not mine). With the straight arm, the distance is greater between shoulder and the hand, creating much more hand speed.

This is why bent arm forehands tend to have a functional backswing, in order to make up the difference from the starting point to the contact point. They need to carry hand speed into the starting point.

Also the bent elbow is less likely to have independent arm motion. Remember the ideal is to have the arm spring through the torso rotation with minimal muscular activity.

I sometimes enjoy getting into the weeds of the strokes to fully appreciate what is actually happening.

Sean

[johnyandell]

Arturo,
Great point on the returns.

[arturohernandez]

One interesting thing about the article is the idea of moving the body in synchrony. My daughter would practice a modified forehand while holding her hitting arm wrist with her left hand. We also do medicine ball throws. A lot of the mechanics are similar to these two motions and she hits with a bent arm. Her forehand is very good. She is compact so she can absorb power quite well.

Also, I wonder if Federer uses more of a bent arm for returns and for some of his forehands that have more feel.

https://www.tennisplayer.net/members/avancedtennis/john_yandell/pro_returns/part_1_compact_classical/