Grips. Index knuckle, heel pad confusion?

[davced1]

Grip instructions are often given as "eastern backhand grip, index knuckle and heel pad on bevel 1". Is it really so? The eastern backhand grip just never felt good when I tried to do that but now I realized that as long as my heel pad is on bevel 1 I have a strong backhand grip probably eastern but I am not sure because my index knuckle is on bevel 2.

My friend who has a great one hander showed me his grip and the knuckle was clearly on bevel 2, I told him that's a continental grip but then he showed me the heel pad, on bevel 1 of course.

For the record this advice seems to hold true for forehand grips but is it really the same for the 1hbh?

Help me sort this out, enough with the confusion.

 

[SystemicAnomaly]

The base index knuckle is the primary reference for the grips. This position is used to establish the name of the grip. The heel pad is a secondary reference. The racket should lie across the palm of the hand diagonally. This will often put the heel pad on the same bevel (or corner) as the base index knuckle.

The simplest grip instructions will usually put both reference points on the same bevel or corner. However, the racket can lie in the hand at an angle where the heel pad will not be on the same level as the primary reference.

The heel pad can often be offset from the knuckle position by a half bevel -- or even as much as a full bevel. When I was studying the official grip descriptions for USPTA coaching certification (in the early 00s?), they had the heel pad offset from the knuckle position by a half or full bevel. However, these grip descriptions were eventually simplified to where both references were on the same bevel. This simplified description was pretty much the same descriptions I learned in the mid/late 90s.

 

[davced1]

The base index knuckle is the primary reference for the grips. This position is used to establish the name of the grip. The heel pad is a secondary reference. The racket should lie across the palm of the hand diagonally. This will often put the heel pad on the same bevel (or corner) as the base index number.

The simplest grip instructions will usually put both reference points on the same bevel or corner. However, the racket can lie in the hand at an angle where the heel pad will not be on the same level as the primary reference.

The heel pad can often be offset from the knuckle position by a half bevel -- or even as much as a full bevel. When I was studying the official grip descriptions for USPTA coaching certification (in the early 00s?), they had the heel pad offset from the knuckle position by a half or full bevel. However, these grip descriptions were eventually simplified to where both references were on the same bevel. This simplified description was pretty much the same descriptions I learned in the mid/late 90s.

Thanks! Then me and my friend must have a continental grip for the backhand. However my grip for 1hbh and slice backhand are slightly different. On both occasions the base index knuckle is on bevel 2 but for the slice its more to the right on the bevel so it must be variations on the continental grip.

 

[SystemicAnomaly]

Thanks! Then me and my friend must have a continental grip for the backhand. However my grip for 1hbh and slice backhand are slightly different. On both occasions the base index knuckle is on bevel 2 but for the slice its more to the right on the bevel so it must be variations on the continental grip.

It is not uncommon to have continental grips that are different for serves, volleys & groundstrokes. Even IF the bass index knuckle is squarely on bevel 2 for these different shots, the heel pad positioning might differ from one type of shot to the next. Many players will have 2 versions of the continental. (It is conceivable that a some players might have 3 versions, but this might be rare)

 

[Dragy]

Two guys with different approach to BH gripping:

 

[Chas Tennis]

Grip instructions are often given as "eastern backhand grip, index knuckle and heel pad on bevel 1". Is it really so? The eastern backhand grip just never felt good when I tried to do that but now I realized that as long as my heel pad is on bevel 1 I have a strong backhand grip probably eastern but I am not sure because my index knuckle is on bevel 2.

My friend who has a great one hander showed me his grip and the knuckle was clearly on bevel 2, I told him that's a continental grip but then he showed me the heel pad, on bevel 1 of course.

For the record this advice seems to hold true for forehand grips but is it really the same for the 1hbh?

Help me sort this out, enough with the confusion.

The way to sort it out is to
Google: ATP one hand backhand close up pictures

Many instructions say to place the racket on the fat pad but for many grips the racket butt ends at the area of the little finger. See pictures of ATP pros one hand backhand grips.

 

[davced1]

Two guys with different approach to BH gripping:

What is the difference you mean? Looks about the same to me.

 

[Chas Tennis]

Thread on the Fat Pad issue.

For the high level forehand, one hand backhand and the serve, the fat pad is most often not contacted by the racket. That's my opinion looking at high level stroke videos and pictures. But when I look at most instructions the 'fat pad' or 'heel pad' is used as a reference point. True or false?

Google: tennis grips hand placement
https://www.google.com/search?q=gri...FeD4KHaNkDIIQsAQIHA&biw=1366&bih=891&dpr=0.87

 

[SystemicAnomaly]

What is the difference you mean? Looks about the same to me.

The shape of these backhands are somewhat the same. However the exact positioning is slightly different. Stephanos, in the bottom image, has his base index knuckle pretty much squarely on the top bevel (bevel 1). This is a variation of the EBh grip. Unlike a more standard version of the EBh grip, the heel pad position does not appear to be on the same bevel. Somewhat closer to bevel 8 from what I can tell.

Dominic's base index knuckle is slightly shifted forward on bevel 1 -- a skosh toward bevel 2 (but still primarily on bevel 1). His heel pad, like that of ST is offset (about bevel 8).

Take a close look at the top knuckles of each finger for both DT and ST. These knuckles are not quite in a straight line but they are at a slight angle from the horizontal. If the heel pad was on the same bevel as the (top) base index knuckle, the top knuckles of the other fingers would be at more of a downward angle

 

[Chas Tennis]

What is the difference you mean? Looks about the same to me.

One difference is that Thiem closes his eyes on ground strokes.

 

[Dragy]

What is the difference you mean? Looks about the same to me.

Stefanos has his hand as diagonal as you may go. Dominic is closer to perpendicular, closes fist gripping. Stefanos has his big finger touching middle finger, while index finger is set away - like “pistol” grip. Dominic, again, has closed fist with big finger over the index finger.

I believe they have heel pad on same bevel, but index knuckles are located differently as @SystemicAnomaly explained.

 

[Chas Tennis]

QUICK STATS
It helps to have a racket in your hand.

Here are some pictures where grips can be seen.

Google: tennis strokes close up grips pictures

tennis strokes close up grips pictures - Google Search

Look for pictures where the butt of the racket handle goes farther than the little finger area. %
Look for pictures where the butt of the racket handle ends around the little finger. %

Note whether the pictures are ATP players.
Note whether the pictures are internet instructional websites for the grip.

Can you find ATP players where the handle butt goes much past the little finger?

Note - I believe that Semi-Western and Western grips can have the handle butt past the little finger area and it does not make a difference to the forearm-to-racket-shaft angle. I don't see that the fat pad or heel pad is touched for those grips, or most other ATP grips.

Are the Western Forehand Grip and Eastern Backhand Grip the same, but the hand is under the handle for the WFG and over the handle for the EBG?

 

[Chas Tennis]

Excellent pictures of Federer's and Djokovic's grips.

Close enough?

 

[Chas Tennis]

Using Fat Pad instead of the little finger area changes the forearm-to-racket shaft angle.

Tennis Grips - Usually the Fat Pad Doesn't touch ANYTHING! ?

For the high level forehand, one hand backhand and the serve, the fat pad is most often not contacted by the racket. That's my opinion looking at high level stroke videos and pictures. But when I look at most instructions the 'fat pad' or 'heel pad' is used as a reference point. True or...

tt.tennis-warehouse.com

From this earlier thread -

"I held the racket from the index knuckle to the fat pad and then to the little finger wrap around area. The blue line represents bevel #2 to the fat pad. The red line represents bevel #2 to the area of the little finger. The two "T"'s at the ends of each line were traces of the end of bevel #2.

This shows the forearm-to-racket shaft angle for the fat pad (blue) and the little finger area (red).

This is bevel #2 resting on the fat pad, blue line. Note the angle between the forearm and the racket.

This is bevel #2 to the area where the little finger wraps around the butt of the racket, red line. Note the decreased angle between the forearm and racket. I measured the angular difference between the red and blue lines on the hand in the first picture with a protractor as 10 degrees.

The two figures shown are applicable to the forearm-to-racket angle on the serve.

In my opinion, 10 degrees is a large angle in biomechanics and especially for the forearm-to-racket angle for the serve. One point is that the kick serve has a smaller forearm-to-racket angle at impact."

 

[davced1]

So do I have a continental or an eastern backhand grip?

 

[SystemicAnomaly]

So do I have a continental or an eastern backhand grip?

It's a Conti variation. As I indicated previously, the base index knuckle is usually taken to be the primary reference. The heel pad placement will determine variations of the base grip

 

[Curious]

So do I have a continental or an eastern backhand grip?

I believe Federer has the same grip as this on his topspin backhand. Does anyone have close up pictures of his grip?

 

[Dragy]

I believe Federer has the same grip as this on his topspin backhand. Does anyone have close up pictures of his grip?

Fed grip is a bit different. Thumb between index and middle finger, and index knuckle more over the edge between 1-2 bevel

 

[Dragy]

 

[Curious]

index knuckle more over the edge between 1-2 bevel

Thanks. I knew it didn’t quite look eastern. Heel pad on bevel 1 though, agree?

 

[Dragy]

Thanks. I knew it didn’t quite look eastern. Heel pad on bevel 1 though, agree?

I think so, he isn’t fully diagonal (like Tsitsipas). He’s just conservative, but it’s a OHBH topspin grip, not conti.

 

[Chas Tennis]

Two guys with different approach to BH gripping:

The Eastern backhand grip lends itself to easy adjustment for ball impact height. A single frame does not show the variety that may be out there in the ATP. I guess that these two grips are similar the Western Grip and Semi-Western Grip on forehands, only upside down.

 

[Chas Tennis]

....................................................................................................

My friend who has a great one hander showed me his grip and the knuckle was clearly on bevel 2, I told him that's a continental grip but then he showed me the heel pad, on bevel 1 of course.
...................................................

The OP should not take the grip used by his friend as a model. Why not ATP grips?

For what to believe about the heel pad, look at 10 ATP players and see how many have the racket butt in contact with the heel pad vs the little finger area.
Google: One hand backhand impact pictures

Gasquet has a special butt cap modification, so that the little finger area and heel pad are both very close. To single frame on Vimeo hold down the SHIFT KEY and use the ARROW KEYS.

Try not to see chest press. (on upper arm) Try not to see Scapulothoracic Protraction. (shoulder forward)

 

[Dragy]

The Eastern backhand grip lends itself to easy adjustment for ball height impact. A single frame does not show the variety that may be out there in the ATP. I guess that these two grips are similar the Western Grip and Semi-Western Grip forehands, only upside down.

They definitely grip it "somehow different" for BH vs FH. For example, it's very rare to see (if any) a grip like Thiem on FH side. W grips on FH commonly have "pistol" index finger, to some degree.

 

[Dragy]

And there are better ways to play BH than taking it high, and better solutions than using stronger grips. Occasionally, one can play high balls even with conti grip, just tough to put topspin on it. But better thing - move up or move down and play it with preferred grip at some good height.

 

[Chas Tennis]

And there are better ways to play BH than taking it high, and better solutions than using stronger grips. Occasionally, one can play high balls even with conti grip, just tough to put topspin on it. But better thing - move up or move down and play it with preferred grip at some good height.

I had an instructor that told me, 'high balls don't need topspin'. He advised to use side spin on high balls. Prior to asking him, I was trying to put top spin on everything and having trouble especially on the high 1 hand backhand, like a lot of people. I can't say it is the preferred way to hit a high ball, it helped me out of a lot of backhand weakness. I have seen the side spin for high balls in the ATP but never tried to get the stats on what percent are side spin and at what height the side spin should first be used.

 

[Curious]

I had an instructor that told me, 'high balls don't need topspin'. He advised to use side spin on high balls. Prior to asking him, I was trying to put top spin on everything and having trouble especially on the high 1 hand backhand, like a lot of people. I can't say it is the preferred way to hit a high ball, it helped me out of a lot of backhand weakness. I have seen the side spin for high balls in the ATP but never tried to get the stats on what percent are side spin and at what height the side spin should first be used.

Same on the forehand side.

 

[SystemicAnomaly]

I believe Federer has the same grip as this on his topspin backhand. Does anyone have close up pictures of his grip?

Your grip appears to be a Continental variation. This is not Roger's topspin Bh grip. Most sources have him using an EBh grip or a modified EBh grip. Very close to a standard EBh (which has the base index knuckle and heel pad on bevel 1). In Roger's case, he is primarily on bevel 1 but shaded slightly toward the edge between bevels 1 and 2

Federer Backhand Grip - Understanding The Roger Federer Backhand Grip - Tennis Instruction

Players around the world admire Federer’s backhand as one of the most elegant in the game today. While Roger Federer’s forehand gets a lot of press, especially the inside-out version, his elegant backhand can sometimes get overlooked in the hubbub over his mysterious forehand grip and stroke...

tennisinstruction.com

 

[Dragy]

I had an instructor that told me, 'high balls don't need topspin'. He advised to use side spin on high balls. Prior to asking him, I was trying to put top spin on everything and having trouble especially on the high 1 hand backhand, like a lot of people. I can't say it is the preferred way to hit a high ball, it helped me out of a lot of backhand weakness. I have seen the side spin for high balls in the ATP but never tried to get the stats on what percent are side spin and at what height the side spin should first be used.

On high balls you noticeably add sidespin and end with diagonal spin. Going with close-to-pure sidespin is quite a limited option:
- it’s very good when hitting aggressively and low over the net, attacking high ball; mostly speaking for FH side
- it’s good to kill some pace and add control when hitting deep-to-deep with strong cut
- it’s not good when on defensive, as it’s tough to find balance between landing it short (and it sits up with no kick) and floating long (as it doesn’t dip down)

Once again, if talking BH side, and receiving a shot which kicks high and pushes me, I go to either of the options:
- take it on the rise; works if I can get behind the ball, but hard if need to move laterally to reach for it
- fall back and play high arcing topspin + sidespin a-la Thiem (but not going for same brute power obviously, more of heavy spin high arc moderate speed) - if I have space to lift it, it’s much easier to make high contact
- play high slice with sidespin, going around the outer part of the ball; this option is also sidespin, but skids and stays low more, even if goes shorter; or flows deeper, if goes higher - both safe neutralizing outcomes

 

[Chas Tennis]

Your grip appears to be a Continental variation. This is not Roger's topspin Bh grip. Most sources have him using an EBh grip or a modified EBh grip. Very close to a standard EBh (which has the base index knuckle and heel pad on bevel 1). In Roger's case, he is primarily on bevel 1 but shaded slightly toward the edge between bevels 1 and 2

Federer Backhand Grip - Understanding The Roger Federer Backhand Grip - Tennis Instruction

Players around the world admire Federer’s backhand as one of the most elegant in the game today. While Roger Federer’s forehand gets a lot of press, especially the inside-out version, his elegant backhand can sometimes get overlooked in the hubbub over his mysterious forehand grip and stroke...

tennisinstruction.com

Pictures of Federer's one hand backhand grip show the butt of the racket ending at his little finger.

Google: federer one hand backhand pictures

Many Federer 1HBH pictures are found.

When I clicked on this picture, it appears to the right and there is an icon next to it. That icon is for a Google image search capability to do a picture search. You can do quick stats on this type of image in very little time.

You can find pictures of the heel pad being used and the little finger area being used during ATP tennis strokes. I've posted for years on this issue with evidence.

It's important because heel pad vs little finger area also changes the forearm-to-racket shaft angle.

Could you show heel pads being used in ATP strokes? %?

 

[Jonesy]

Grip instructions are often given as "eastern backhand grip, index knuckle and heel pad on bevel 1". Is it really so? The eastern backhand grip just never felt good when I tried to do that but now I realized that as long as my heel pad is on bevel 1 I have a strong backhand grip probably eastern but I am not sure because my index knuckle is on bevel 2.

My friend who has a great one hander showed me his grip and the knuckle was clearly on bevel 2, I told him that's a continental grip but then he showed me the heel pad, on bevel 1 of course.

For the record this advice seems to hold true for forehand grips but is it really the same for the 1hbh?

Help me sort this out, enough with the confusion.

 

[Chas Tennis]

Original. To single frame on Youtube stop video and use the period & comma keys.

Reality. Blue line shows angle of racket handle to the fat pad. Red line shows angle of racket shaft to the little finger area. The angle affects the forearm-to-racket shaft angle. Try it with a racket.

Tennis Grips - Usually the Fat Pad Doesn't touch ANYTHING! ?

For the high level forehand, one hand backhand and the serve, the fat pad is most often not contacted by the racket. That's my opinion looking at high level stroke videos and pictures. But when I look at most instructions the 'fat pad' or 'heel pad' is used as a reference point. True or...

tt.tennis-warehouse.com

Cut & Paste World

Google Search

Tennis Racket Grip - What is true?

 

[Friedman Whip]

Grip instructions are often given as "eastern backhand grip, index knuckle and heel pad on bevel 1". Is it really so? The eastern backhand grip just never felt good when I tried to do that but now I realized that as long as my heel pad is on bevel 1 I have a strong backhand grip probably eastern but I am not sure because my index knuckle is on bevel 2.

My friend who has a great one hander showed me his grip and the knuckle was clearly on bevel 2, I told him that's a continental grip but then he showed me the heel pad, on bevel 1 of course.

For the record this advice seems to hold true for forehand grips but is it really the same for the 1hbh?

Help me sort this out, enough with the confusion.

I think you've asked a very good question. Personally on all of my 3 grips, topspin BH, serve and FH, my heel pad is 1/2 bevel different from the base knuckle. Putting pad and knuckle on same bevel has never felt as stable to me as being offset a bit.

 

[optic yellow]

Original. To single frame on Youtube stop video and use the period & comma keys.

Reality. Blue line shows angle of racket handle to the fat pad. Red line shows angle of racket shaft to the little finger area. The angle affects the forearm-to-racket shaft angle. Try it with a racket.

Tennis Grips - Usually the Fat Pad Doesn't touch ANYTHING! ?

For the high level forehand, one hand backhand and the serve, the fat pad is most often not contacted by the racket. That's my opinion looking at high level stroke videos and pictures. But when I look at most instructions the 'fat pad' or 'heel pad' is used as a reference point. True or...

tt.tennis-warehouse.com

Cut & Paste World

Google Search

Tennis Racket Grip - What is true?

What is difference between the racquet handle and racquet shaft?

 

[Chas Tennis]

What is difference between the racquet handle and racquet shaft?

The orientation of the racket shaft is always easier to see than the handle. What you see in a video is 2D but the racket shaft and the forearm are in 3D space - so you have to be careful to remember that when estimating - it is often not very accurate. Take a paper clip and straighten it. Put a bend in it. Hold one end and rotate it. The apparent angle changes as you rotate the clip.

 

[optic yellow]

The orientation of the racket shaft is always easier to see than the handle. What you see in a video is 2D but the racket shaft and the forearm are in 3D space - so you have to be careful to remember that when estimating - it is often not very accurate. Take a paper clip and straighten it. Put a bend in it. Hold one end and rotate it. The apparent angle changes as you rotate the clip.

I don't see a shaft on a tennis racquet expect the part that I would call the handle.

 

[Chas Tennis]

I don't see a shaft on a tennis racquet expect the part that I would call the handle.

You have a point.

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The racket has a long axis, running through the center of the butt cap to the tip of the racket and beyond. How that long axis tilts 'closed' for the serve at impact is very important. The long axis angle determines where the racket face first contacts the ball. Try it. It's important also for ground strokes, but we have few overhead camera videos to use it. For analysis, I want that long axis direction and don't look at the part of the racket blocked by the hand, commonly called the 'handle'. The forearm-to-racket shaft angle is also useful for stroke analysis to connect the arm and the important racket long axis (I say 'shaft'.)

 

[SystemicAnomaly]

What is difference between the racquet handle and racquet shaft?

Can you handle being shafted?

 

[optic yellow]

You have a point.

Account Temporary On Hold

The racket has a long axis, running through the center of the butt cap to the tip of the racket and beyond. How that long axis tilts 'closed' for the serve at impact is very important. The long axis angle determines where the racket face first contacts the ball. Try it. It's important also for ground strokes, but we have few overhead camera videos to use it. For analysis, I want that long axis direction and don't look at the part of the racket blocked by the hand, commonly called the 'handle'. The forearm-to-racket shaft angle is also useful for stroke analysis to connect the arm and the important racket long axis (I say 'shaft'.)

What does 'closed' mean? In what dimension and in reference to what? I understand the concept of the 'shaft' as the long axis of the racquet.

 

[optic yellow]

Also for groundstrokes the purpose is to manipulate sidespin and horizontal launch angle in conjunction with the swingpath.

 

[Chas Tennis]

What does 'closed' mean? In what dimension and in reference to what? I understand the concept of the 'shaft' as the long axis of the racquet.

When I learned the use of the term 'closed' for tennis, it was used in a defined way. Closed meant that the highest point on the racket face was forward more than the bottom edge in the direction of racket travel. If the racket were moving forward slowly, a 'closed face' would direct the ball more down. If 'open' it would direct the ball up. It was a defined tennis term in how it was used. ( I hope that it still is for serious tennis players somewhere, because it was useful for communication.)

Here on the forum many posters use the terms 'open' or 'open up' for the horizontal direction. I do not believe the term is defined in forum usage. The term open of closed was very useful, but now the other forum usages make readers uncertain of the meaning.

In a scientific field, defined terms are widely used so that you don't have to explain what your terms mean every time time that you use them. Here the discussions are becoming more scientific, but the undefined conversational terms make communication to readers ambiguous. Worse, is to take a defined term in biomechanics and use it incorrectly for the poster's thought. Usage of the term Pronation during the tennis serve is the flagship of incorrect tennis usage.

How Science Describes the Orientation of a Surface, Plane or Curved. To describe the orientation of surface like the racket face, science uses the normal to the surface. The normal is a line that is perpendicular to the surface at a point. For the racket face instead of saying 'open'. You could say the face of the racket is point up by 10 degrees, meaning the normal is pointing 10 degrees above the horizontal direction. But most people don't know what a normal is. The normal also works well for curved surfaces too, since it is defined for a point on the curved surface.

Normal (geometry) - Wikipedia

en.wikipedia.org

Normal Vector -- from Wolfram MathWorld

The normal vector, often simply called the "normal," to a surface is a vector which is perpendicular to the surface at a given point. When normals are considered on closed surfaces, the inward-pointing normal (pointing towards the interior of the surface) and outward-pointing normal are usually...

mathworld.wolfram.com

.

 

[Chas Tennis]

This picture shows the butt of the racket going beyond the little finger area. Maybe that is the fat pad? Unlike this picture, most ATP grips that I have seen have the butt ending very near to the little finger area. If you are interested in what is true for this issue. Google: ATP tennis close up pictures count fat pad vs little finger area - post your results

Account Temporary On Hold

 

[optic yellow]

When I learned the use of the term 'closed' for tennis, it was used in a defined way. Closed meant that the highest point on the racket face was forward more than the bottom edge in the direction of racket travel. If the racket were moving forward slowly, a 'closed face' would direct the ball more down. If 'open' it would direct the ball up. It was a defined tennis term in how it was used. ( I hope that it still is for serious tennis players somewhere, because it was useful for communication.)

Here on the forum many posters use the terms 'open' or 'open up' for the horizontal direction. I do not believe the term is defined in forum usage. The term open of closed was very useful, but now the other forum usages make readers uncertain of the meaning.

In a scientific field, defined terms are widely used so that you don't have to explain what your terms mean every time time that you use them. Here the discussions are becoming more scientific, but the undefined conversational terms make communication to readers ambiguous. Worse, is to take a defined term in biomechanics and use it incorrectly for the poster's thought. Usage of the term Pronation during the tennis serve is the flagship of incorrect tennis usage.

How Science Describes the Orientation of a Surface, Plane or Curved. To describe the orientation of surface like the racket face, science uses the normal to the surface. The normal is a line that is perpendicular to the surface at a point. For the racket face instead of saying 'open'. You could say the face of the racket is point up by 10 degrees, meaning the normal is pointing 10 degrees above the horizontal direction. But most people don't know what a normal is. The normal also works well for curved surfaces too, since it is defined for a point on the curved surface.

Normal (geometry) - Wikipedia

en.wikipedia.org

Normal Vector -- from Wolfram MathWorld

The normal vector, often simply called the "normal," to a surface is a vector which is perpendicular to the surface at a given point. When normals are considered on closed surfaces, the inward-pointing normal (pointing towards the interior of the surface) and outward-pointing normal are usually...

mathworld.wolfram.com

.

So you draw a vector in the same direction as the racquets travel and use that as the normal vector to define a plane then you can measure the deviation of the racquet face from that ideal plane using its own normal vector which then describes spin generation and launch angle when adjusted for whatever factors there are with ball-string surface interaction.

 

[Chas Tennis]

So you draw a vector in the same direction as the racquets travel and use that as the normal vector to define a plane then you can measure the deviation of the racquet face from that ideal plane using its own normal vector which then describes spin generation and launch angle when adjusted for whatever factors there are with ball-string surface interaction.

If the highest racket edge is more forward than the lowest edge, the racket is closed. Forward is also in the direction of the racket motion.

TennisSpeed Research: A Roadmap to a Hall-of-Fame Forehand - Part 1: What is the Racket Really Doing in the Impact Zone?

tennisspeedresearch.blogspot.com

Tennisspeed has the ideal way to show open and closed.

Side camera view.

1) Forward direction of stroke.
2) The top racket edge is more forward than the bottom racket edge.

This racket is closed at impact (green) and impact closes it more (red).

Closed gives you the orientation of the racket face relative to gravity. That is very important for how far the ball travels. In biomechanics, the angle of a ball trajectory to the horizontal is called the 'projection' angle. Closed and open are important for the projection angle.

Take a racket in your hand, imagine the ball on the racket face at impact. Imagine open and closed.

Tennis usage of term 'closed'. Link.

Google Search

Forum usage of term 'closed'? It is muddling the use of the term 'closed' on the forum.

 

[optic yellow]

If the highest racket edge is more forward than the lowest edge, the racket is closed. Forward is also in the direction of the racket motion.

TennisSpeed Research: A Roadmap to a Hall-of-Fame Forehand - Part 1: What is the Racket Really Doing in the Impact Zone?

tennisspeedresearch.blogspot.com

Tennisspeed has the ideal way to show open and closed.

Side camera view.

1) Forward direction of stroke.
2) The top racket edge is more forward than the bottom racket edge.

This racket is closed at impact (green) and impact closes it more (red).

Closed gives you the orientation of the racket face relative to gravity. That is very important for how far the ball travels. In biomechanics, the angle of a ball trajectory to the horizontal is called the 'projection' angle. Closed and open are important for the projection angle.

Take a racket in your hand, imagine the ball on the racket face at impact. Imagine open and closed.

Tennis usage of term 'closed'. Link.

Google Search

Forum usage of term 'closed'? It is muddling the use of the term 'closed' on the forum.

Why do they call it projection angle rather than launch angle? I mostly got what you were saying with closed I was trying to let you know I understood the concept of the normal vectors and agreed with using it. I see how it is useful to oriented open-closed with the component of racquet tilt in that plane. That seems to be the practical effect of defining by whatever is the highest point on the racquet hoop.

 

[Chas Tennis]

Why do they call it projection angle rather than launch angle? I mostly got what you were saying with closed I was trying to let you know I understood the concept of the normal vectors and agreed with using it. I see how it is useful to oriented open-closed with the component of racquet tilt in that plane. That seems to be the practical effect of defining by whatever is the highest point on the racquet hoop.

'Projection angle' is a defined term in biomechanics. The projection angle is a large factor in determining the range of throwing or hitting a ball. Look up the definition of projection angle in biomechanics. Once a term is defined in some field and useful - don't use that specific term in an undefined way where it is ambiguous.

'Launch angle' is often used for rocket launches.

Get a reference on Kinesiology. Get a reference on Biomechanics.

Shop for a cheap copy of The Biomechanics of Advanced Tennis, 2003, B. Elliott et al. For about 15 years, that ITF book was $275.00. Once you are into biomechanics with defined terms, science is set up to take on change as new things are learned.

The terms 'Projection Angle', 'open' and 'closed' relate to ball's trajectory and the direction of gravity being important on earth. That is why the terms came into first use for tennis and biomechanics - how far is the ball going to go?

Saying 'I opened up early on the forehand' is a different usage, not related to the vertical direction of gravity.

 

[optic yellow]

'Projection angle' is a defined term in biomechanics. The projection angle is a large factor in determining the range of throwing or hitting a ball. Look up the definition of projection angle in biomechanics. Once a term is defined in some field and useful - don't use that specific term in an undefined way where it is ambiguous.

'Launch angle' is often used for rocket launches.

Get a reference on Kinesiology. Get a reference on Biomechanics.

Shop for a cheap copy of The Biomechanics of Advanced Tennis, 2003, B. Elliott et al. For about 15 years, that ITF book was $275.00. Once you are into biomechanics with defined terms, science is set up to take on change as new things are learned.

The terms 'Projection Angle', 'open' and 'closed' relate to ball's trajectory and the direction of gravity being important on earth. That is why the terms came into first use for tennis and biomechanics - how far is the ball going to go?

I'm not doubting this I literally was just curious why that is the term they used. Yes launch angle is used for rocket launches but there is not fundamentally any difference between a rocket and a tennis ball - both are projectiles released with energy to fight against or work with Earth's gravity. I'm not asking you to defend it, just explain if you know.

Saying 'I opened up early on the forehand' is a different usage, not related to the vertical direction of gravity.

What does this mean?