Physics question: Is power all about racquet head speed?

HunterST

HunterST

Hall of Fame
Obviously the weight of the racquet and the strings affect power also. But in terms of technique and what the player produces, is it all about racquet head speed? Or does the mass of the player come into play as well?

I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.

Obviously it won't affect proper technique either way, but I think it would help to know the physics behind it.
 
Yes, power is about Force.
That force does come from racket head speed.
A lighter racket may, however, lose some forward momentum from impact with the ball
A heavier racket swung at the same speed may impart slightly more force because it is less affected overcoming the force of the opponent's ball,
but that same player may be less able to bring a heavy racket up to the same head speed as a lighter racket.
Path of racket through ball may result in spin- converting some forward momentum into ball rotation which would slow the ball and cause
an arcing that (assuming it lands in the same spot as a "flat" ball) makes it travel a slightly greater distance and lose a bit of speed.
Hitting a "flat" groundstroke may force the player to consciously lessen RHS to avoid hitting long.

A weak player or a player with poor timing and poor form may not be able to take advantage of pure RHS.
A muscle-bound player may not play with the looseness needed to generate RHS.
 
Note that the physics definition of power is somewhat different than the way it is defined for kinesiology / muscle movement.

In physics, power is the amount of energy transferred or converted per unit time. Power is the rate (wrt time) at which work is done. P= W/t

(Electric power is the product of current & voltage. P = IV. For vehicles or motors, power is defined a bit differently).

Contrast this with the way the term, power, is used in kinesiology. Here, it defined as the ability to exert force in the shortest amount of time. While this sounds similar, it is a bit different. Here we are talking about applying a force whereas, in physics, it is a Work rate or the rate of energy transfer (or conversion)

For kinesiology, power can also be defined as the rate at which ATP (adenosine triphosphate) is utilized during a maximal effort against a sub-maximal load.

Confusing, huh?
 
Force = Mass X Acceleration

So, the mass of your racquet and the acceleration of your swing contribute to the force you generate. But the racquet is a stringed tool and so, the stiffness of the racquet, stiffness of the stringbed and the elasticity of the strings all contribute to how much energy is transmitted to the ball which also affects the launch angle and depth of the shot.
 
HunterST said:
I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.
Click to expand...
You can hit very hard falling back, it’s more about how you creat RHS in a well-controlled, reliable manner, and whether you make clean contact. If you use your legs, you also get different alignment of this force when you push up staying in place and when you shift forward — hence even same RHS may create more steep swingpath vs more linear. So if you are overall comfortable with hitting while stepping forward, you may achieve higher ball speed.

From physics perspective, body mass doesn’t have direct effect on the collision during the 3-5ms when it happens. But with good technique swing quality is directly related with whole body movement — we do use all of it to perform proper swings.
 
It’s about bio mechanical principles and kinetic chain implementation.
Bio mechanical principles include
Balance, inertia, opposite force, momentum, elastic energy and coordination.
Racquets and strings do play a role
With kinetic energy you are looking at:
1. Performing links in the right order, without emitting a chain, at the right amount and the right speed;
 
Dragy said:
You can hit very hard falling back, it’s more about how you creat RHS in a well-controlled, reliable manner, and whether you make clean contact. If you use your legs, you also get different alignment of this force when you push up staying in place and when you shift forward — hence even same RHS may create more steep swingpath vs more linear. So if you are overall comfortable with hitting while stepping forward, you may achieve higher ball speed.

From physics perspective, body mass doesn’t have direct effect on the collision during the 3-5ms when it happens. But with good technique swing quality is directly related with whole body movement — we do use all of it to perform proper swings.
Click to expand...
I know someone here who uses your avatar as their tennis logo
 
Simple answer is no. If you could hit the ball absolutely flat along a linear swing path then Yes. Problem is you can’t cuz because your arm is connected to your shoulder. Your path is curved so you’ll impart a vertical and horizontal path to hit ball.

When you ‘step into’ the ball you are adding body mass momentum which is a significant amount of added energy in the ball return. Look at a basebsll batter when they swing. They almost always shift their body when they swing.
 
HunterST said:
Obviously the weight of the racquet and the strings affect power also. But in terms of technique and what the player produces, is it all about racquet head speed? Or does the mass of the player come into play as well?

I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.

Obviously it won't affect proper technique either way, but I think it would help to know the physics behind it.
Click to expand...
The heavier the racket, the harder you can hit, but usually the weight of the head is what counts.

Roger and Rafael add a lot of lead at 12 o'clock for power, I did it once as an experiment, the head literally pulls forward...(it is unstoppable)



Due to putting so much lead on the head, and also playing the head close to the ground, it is very difficult to swing if you want to make a really perfect swing.



But no amateur would put so much lead tape in his racquet, if anything, much less, I'll point out what it looks like if you want a lot of power from the racquet...
 
Last edited:
HunterST said:
Obviously the weight of the racquet and the strings affect power also. But in terms of technique and what the player produces, is it all about racquet head speed? Or does the mass of the player come into play as well?

I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.

Obviously it won't affect proper technique either way, but I think it would help to know the physics behind it.
Click to expand...
Power is defined in physics. Power has a conservational usage in tennis, always undefined unless defined. A zoo of usage.

Some power has been used in tennis analysis. I don't think it is well known or often used. R. E. Bahamonde? Jan 2001. Biomechanics of forehand stroke. Hardly anyone understands.

'Stepping into the ball weight transfer' is a linear ground stroke technique. That differs from the more modern circular technique. Search "I'm on Your Side Tennis", forehand, by Dan Brown. Listen carefully many times to what Dan says and illustrates for the linear vs circular forehand. If the head does not move forward, it probably is not a 'step forward weight transfer' stroke but a circular stroke.
 
Last edited:
In physics power is instantaneous. Energy per unit time. If a racket impacts a ball, the power varies greatly as the ball and strings distort and interact. Power is 0 watts before and after ball and string contact.

Power vs time could also be considered as the body accelerates the racket. The uppermost body turn has significant power transfer as it accelerates the racket. But if power suddenly is shut off when the racket is moving at 100 MPH during the serve, then the racket head continues at 100 MPH with small losses to impact the ball and suddenly transfer power to the ball for about 4 milliseconds. Power is very difficult to measure compared to velocity. Power is measured as watts vs time. What are peak watts during racket-ball Impact? What are watts vs time during a forehand. Power has an undefined conversational usage in tennis..

That being said, looking at high speed videos, the parts of the body, joint movements, that the power is coming from can be seen in videos because they show accelerations. FORCE = MASS X ACCELERATION. You are not going to get anything quantitative, similar to racket head speed or ball velocity, which can be easily measured. If a ball is struck and acquires energy in 4 milliseconds of string contact then the average power was energy / 4 milliseconds.

It is useful to imagine that you get what you are after. Then what?

If you know watts per unit time for everything in a tennis stroke, what do you have?
 
Last edited:
Chas Tennis said:
'Stepping into the ball weight transfer' is a linear ground stroke technique. That differs from the more modern circular technique. Search "I'm on Your Side Tennis", forehand, by Dan Brown. Listen carefully many times to what Dan says and illustrates for the linear vs circular forehand. If the head does not move forward, it probably is not a 'step forward weight transfer' stroke but a circular stroke.
Click to expand...
That video is too primitive, understanding has gone further onward. Every modern player uses "stepping into" situationally to deliver huge blows on the ball. The key is understanding where and how linear momentum of body movement is converted into circular torso rotation to accelerate the arm and finally racquet head.

And this is ridiculously simple, actually.
 
Dragy said:
That video is too primitive, understanding has gone further onward. Every modern player uses "stepping into" situationally to deliver huge blows on the ball. The key is understanding where and how linear momentum of body movement is converted into circular torso rotation to accelerate the arm and finally racquet head.

And this is ridiculously simple, actually.
Click to expand...

I agree that 'Step forward weigth transfer' is being done in tennis. But when the players are not pressured, not running, and have their choice of techniques, what percentage are circular vs linear? In other words, what is their preferred technique when they have a choice.

Have you observed the head motions of ATP players to see if their heads move foreward during their forehands? I have for some time, but I have not done statistics to see what percentage are circular. But I believe that the large majority are circular and that the lack of head motion indicates it.
 
Last edited:
Chas Tennis said:
I agree that 'Step forward weigth transfer' is being done in tennis. But when the players are not pressured, not running, and have their choice of techniques, what percentage are circular vs linear? In other words, what is their preferred technique when they have a choice.

Have you observed the head motions of ATP players to see if their heads move foreward during their forehands? I have for some time, but I have not done statistics to see what percentage are circular. But I believe that the large majority are circular and that the lack of head motion indicates it.
Click to expand...
Always when players hit a sitter ball from the baseline, when they have ton of time, they setup and hit in a specific way, which includes transferring forward.

What you possibly fail to see, transferring forward doesn’t mean linear and no circular. It’s just more reliable way to create momentum before converting it for the swing, preferred when there’s time and space. When there’s limited time, they load in place and unload rotating without forward movement, or sometimes even shifting back.
 
I think the main purpose of using lift and rotation of the body is to increase racket head speed. Even on volleys, you will get a crisper (more powerful) volley if you are moving forward into contact. Core rotation and forward movement increase the speed of the racket into contact. All the other factors, racket weight and SW, string tension, string type, string length and racket stiffness all have an effect on power too. I doubt you would have more power if you gain 40 lbs.
 
Dragy said:
Would you plant your front foot before impact when moving forward on volleys? What thoughts does it bring?
Click to expand...
Some coaches would say that contact comes before you plant the lead foot - plant the back foot and push forward off the back foot, then contact as you are moving forward and then catch weight on front foot. On many volleys, I think this is true. Obviously, volleying is dynamic and you may land on front foot before contact but you would continue to move forward catch your weight as the rear foot lands. In some cases, volleys are totally without forward movement if it is reflex block. Personally, I don't overthink the footwork and try to simply get the strings in the ball's flight and move forward.
 
HunterST said:
Obviously the weight of the racquet and the strings affect power also. But in terms of technique and what the player produces, is it all about racquet head speed? Or does the mass of the player come into play as well?

I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.

Obviously it won't affect proper technique either way, but I think it would help to know the physics behind it.
Click to expand...
Mass of the racket including the mass of part of the lower arm is called the effective mass of the racket. This mass and the RHS appear both in the momentum and kinetic energy terms.

If you hit down on the ball (yes, it can be done), then gravity also adds to the speed.
 
It's all about momentum, which is sort of defined as mass movement, and therefore its units are (mass units)*(speed units). Momentum is what is converted into ball speed at the impact. There is also dissipation, that is a function of string tension and string properties.

When you swing your racquet you create some momentum of its head/hoop. Then, when you strike the ball the momentum is conserved (momemtum of the ball = speed of the ball * mass of the ball) + (momentum of the racquet = speed of the racquet head * mass of the racquet head) before impact = (momemtum of the ball = speed of the ball * mass of the ball) + (momentum of the racquet = speed of the racquet head * mass of the racquet head). Note that momentum is a vector quantity, thus the direction matters. In this process the racquet losses momentum (speed, as the mass of the ball or the racquet does not change).

However, that only works for completely flat shots, and there is more complexity in the physics when thinga are not like that. As the ball also has some rotation inertia, and you will be moving the racquet in a vertical motion (the ball would also moving with a non-zero vertical component) and that would translate into spin, but this phenomenon is tougher to explain. However, here comes into play the energy conservation. The total movement of the ball is divided into linear inertia (previusly explained) + rotational inertia, coming from spin. Energy conservation applies along with momentum conservation. Here the energy of the racquet is 1/2 racquet mass * racquet speed^2. The energy of the ball is 1/2 ball speed * ball mass^2 + 1/2 ball's inertia * spin^2.
 
Dragy said:
Always when players hit a sitter ball from the baseline, when they have ton of time, they setup and hit in a specific way, which includes transferring forward.

What you possibly fail to see, transferring forward doesn’t mean linear and no circular. It’s just more reliable way to create momentum before converting it for the swing, preferred when there’s time and space. When there’s limited time, they load in place and unload rotating without forward movement, or sometimes even shifting back.
Click to expand...
I believe that circular forehand drives without much forward movement of the body are in 2024 being used more than linear forehand drives. The linear and circular drives are shown and perfectly described in the Dan Brown video on forehands. Of the series "I'm on Your Side Tennis"

Any reader can look at 10 ATP forehands and see if the head moves forward or not and post their results in percent.

For reference, head movements can be clearly seen in the Dan Brown video on the forehand. Side camera views only.
 
Last edited:
Chas Tennis said:
The linear and circular drives are shown and perfectly described in the Dan Brown video on forehands. Of the series "I'm on Your Side Tennis"
Click to expand...
No, they are not shown perfectly, it's quite primitive interpretation which makes people, and you among them, misunderstand the role of forward weight transfer in the beginning of shot producing sequence of movements.
 
Chas Tennis said:
Any reader can look at 10 ATP forehands and see if the head moves forward or not and post their results in percent.
Click to expand...
Yeah that's very easy to see. Whenever they get an easier, shorter ball, they use neutral stance and hit with forward shift. Whenever they face pushing, heavy, rising ball, they use open stance and stay more in place (still you can see forward head movement even though most transfer is lateral). I wonder how you cannot see it with your love to videos?

VhEzAEw.png


But the most important thing is all variations - neutral, open, semi-open, with more forward shift, with more upward lift and twist in place, even with backwards shift - all are important and applied situationally. There's no some single mythic ideal way of hitting a forehand. If any, it's how they hit a sitter from the baseline - and it's typically semi-open stance, diagonal weight shift, fade drive.
 
Maybe we can study this watching TV tournaments?
1) see forward motion of head.
2) observe circumstances, running
3) forehand drives.

There is so much running in pro matches that will have to be a factor to somehow consider.

I'm going to watch and see what is going on.

High cameras might show things well if available.
 
I am stuck on a phone for a few days and do not know how to post videos and pictures with a phone.

Toly has high camera composite videos that show circular tennis strokes. There is one of Serena's forehand.

Also, FYB has overhead video of Salazar's forehand with his moving and doing a circular forehand. You see everything relative to this issue and circular forehsnds. I think.

.
 
Last edited:
HunterST said:
Obviously the weight of the racquet and the strings affect power also. But in terms of technique and what the player produces, is it all about racquet head speed? Or does the mass of the player come into play as well?

I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.

Obviously it won't affect proper technique either way, but I think it would help to know the physics behind it.
Click to expand...
In golf the mass of the clubbed is considered as acting independently from the body and even the shaft.

Doubt it would be any difference in another racket sport.

Think of things more as impulse or force over time. Force is ma and go from there.

Energy is conserved, you can consider horizontal and vertical components of velocity, spin and then you get some energy lost in heat, sound etc.

Its important to note its not just impact speed, but also separation speed that will determine ball speed etc, so been able to do work through contact to resist the slowing down during the collision (racket hits ball, ball also hits racket) will basically result in more efficient contact (in golf they measure this as smash factor)
 
TennisCJC said:
Some coaches would say that contact comes before you plant the lead foot - plant the back foot and push forward off the back foot, then contact as you are moving forward and then catch weight on front foot. On many volleys, I think this is true. Obviously, volleying is dynamic and you may land on front foot before contact but you would continue to move forward catch your weight as the rear foot lands. In some cases, volleys are totally without forward movement if it is reflex block. Personally, I don't overthink the footwork and try to simply get the strings in the ball's flight and move forward.
Click to expand...
@Dragy

The planting of the front foot is dependent, to a large degree, on the height of the volley. The way I learned it, perhaps 30 yrs ago, is very much the way that Blair H describes below.

For a majority of volleys, the front foot lands pretty much as the same time that you make contact. However, for very low volleys, weight is often shifted to the front foot earlier. For very high volleys, the front foot lands a bit after contact is made.

 
SystemicAnomaly said:
@Dragy

The planting of the front foot is dependent, to a large degree, on the height of the volley. The way I learned it, perhaps 30 yrs ago, is very much the way that Blair H describes below.

For a majority of volleys, the front foot lands pretty much as the same time that you make contact. However, for very low volleys, weight is often shifted to the front foot earlier. For very high volleys, the front foot lands a bit after contact is made.

Click to expand...
I had some idea, but after review it doesn’t seem to be uniform and true. So nvm.
 
Dragy said:
I had some idea, but after review it doesn’t seem to be uniform and true. So nvm.
Click to expand...
The timing I suggested was not absolute. But, as a general rule of thumb, it worked quite well for me. In both singles & doubs, I spent more time at the net than at the baseline.

For most volleys, the front foot landed very close to impact time. More often than not, that foot landed a bit later for high volleys but somewhat earlier for low volleys.
 
Last edited:
All things being equal (distance from the fulcrum point, contact on strings, angle of contact, technique overall, yadda yadda...) the more force applied, the faster the RHS the more power. But that is REALLY simplified beyond reasonable linear qualification.
 
ITT: Lot's of people trying to show how smart they are, no one has answered OP's question. It wasn't about racquet weights, forces, or definitions of power, he is asking if he fattens himself up will he serve faster.
 
Sometennispun said:
ITT: Lot's of people trying to show how smart they are, no one has answered OP's question. It wasn't about racquet weights, forces, or definitions of power, he is asking if he fattens himself up will he serve faster.
Click to expand...
I did answer his question by pointing out that a part of his lower arm contributes to the effective swinging mass.
 
SystemicAnomaly said:
The timing I suggested was not absolute. But, as a general rule of thumb, it worked quite well for me. In both singles & doubs, I spent more time at the net than at the baseline.

For most volleys, the front foot landed very close to impact time. More often than not, that foot landed a bit later for high volleys but somewhat earlier for low volleys.
Click to expand...
This is also how I've always thought of it (front foot plants before contact for low volleys, after for high ones). But I would like to see if this could be refined, or if there are other thoughts on it.
 
dennis said:
This is also how I've always thought of it (front foot plants before contact for low volleys, after for high ones). But I would like to see if this could be refined, or if there are other thoughts on it.
Click to expand...
See Volley Secrets by Brett Hobden. Youtube 15-20 minutes long.

He has a step forward technique and gives how to do it for various incoming balls and volley paces. Especially look at what he calls, "losing the collision".
 
Last edited:
Dragy said:
Always when players hit a sitter ball from the baseline, when they have ton of time, they setup and hit in a specific way, which includes transferring forward.

What you possibly fail to see, transferring forward doesn’t mean linear and no circular. It’s just more reliable way to create momentum before converting it for the swing, preferred when there’s time and space. When there’s limited time, they load in place and unload rotating without forward movement, or sometimes even shifting back.
Click to expand...
It is the combo of both speed and acceleration and the combo of the linear and circular that Chas mentions, that work together to generate big power. By using a cam effect created by 1st moving towards the contact, then shifting your body mass laterally to some greater or lesser extent... this sets up a similar action for the swing as the next segment of the "multi-segmented" swing known as Type III.

So now the hand can drag the racket first on a very mild, direct arc towards contact, before shifting the arc to a much tighter part of a circle, just before contact, as described by Gordon PhD. THis will G-up the racket head going into contact and multiply the effect of the Mass as it creases force.
 
Last edited:
HunterST said:
Obviously the weight of the racquet and the strings affect power also. But in terms of technique and what the player produces, is it all about racquet head speed? Or does the mass of the player come into play as well?

I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.

Obviously it won't affect proper technique either way, but I think it would help to know the physics behind it.
Click to expand...
In general, ppl with more mass tend to be stronger and can produce more force to hit you harder than smaller folks. Welterweights are typically stronger than featherweights. The added weight usually means more muscle mass. It can also mean more body fat. Can this also add to potential power?

So it stands to reason that ppl with more mass could, more easily, produce more power on tennis strokes — as long as they have halfway decent timing & technique. Hard to say exactly how much of this body mass adds to the effective mass of the racket that they are swinging. Do we add the mass of the forearm? The mass of the whole arm? Or do we add more than this given that more of the body, via the kinetic chain, is used to generate “power” on a stroke.

And how about muscle fiber type? It could very well be more important. If a larger person has a lot more slow twitch fiber (Type I) than fast-twitch fiber (Types IIa and IIx) they might not be able to produce as much power as a smaller person who has & recruits a higher % of fast-twitch fibers.

Too many unkown factors to provide a definitive answer?
 
SystemicAnomaly said:
In general, ppl with more mass tend to be stronger and can produce more force to hit you harder than smaller folks. Welterweights are typically stronger than featherweights. The added weight usually means more muscle mass. It can also mean more body fat. Can this also add to potential power?

So it stands to reason that ppl with more mass could, more easily, produce more power on tennis strokes — as long as they have halfway decent timing & technique. Hard to say exactly how much of this body mass adds to the effective mass of the racket that they are swinging. Do we add the mass of the forearm? The mass of the whole arm? Or do we add more than this given that more of the body, via the kinetic chain, is used to generate “power” on a stroke.

And how about muscle fiber type? It could very well be more important. If a larger person has a lot more slow twitch fiber (Type I) than fast-twitch fiber (Types IIa and IIx) they might not be able to produce as much power as a smaller person who has & recruits a higher % of fast-twitch fibers.

Too many unkown factors to provide a definitive answer?
Click to expand...
Yet among hardest hitting pros are guys like Rublev or Auger-Alliasime. No 60-kilo players though crushing the ball. Maybe for rec players who have less muscle quality some big guys can hit harder.

One of hardest hitters on tour has been Basilashvili using XL Speed racquet.
 
Smecz said:
The heavier the racket, the harder you can hit, but usually the weight of the head is what counts.

Roger and Rafael add a lot of lead at 12 o'clock for power, I did it once as an experiment, the head literally pulls forward...(it is unstoppable)



Due to putting so much lead on the head, and also playing the head close to the ground, it is very difficult to swing if you want to make a really perfect swing.



But no amateur would put so much lead tape in his racquet, if anything, much less, I'll point out what it looks like if you want a lot of power from the racquet...
Click to expand...
You can get it to not pull forward by also adding weight at the top of the handle.

I bet I have more lead on my stick than rog or rafa :) Probably both combined.
 
HunterST said:
Obviously the weight of the racquet and the strings affect power also.
Click to expand...
You may want to think a bit more about your question, if you are really talking about Physics here. "Power" ? Do you mean the velocity of the ball as it goes across the net ? Or the absolute energy on the ball as it hits the opponent racquet?
en.wikipedia.org

Kinetic energy - Wikipedia

en.wikipedia.org en.wikipedia.org
en.wikipedia.org

Momentum - Wikipedia

en.wikipedia.org en.wikipedia.org
www1.grc.nasa.gov

Newton’s Laws of Motion | Glenn Research Center | NASA

Sir Isaac Newton’s laws of motion explain the relationship between a physical object and the forces acting upon it. Understanding this information provides us with the basis of modern physics. What are Newton’s Laws of Motion? An object at rest remains at rest, and an object in motion remains in...
www1.grc.nasa.gov www1.grc.nasa.gov

My guess is that you are really talking about the velicity of the ball
In general, the instantanious velocity change on theball during contact is affected by
1. the mass of the racquet,
2. the instantatnious velocity of the racket
3. the force being applied on the racquet (by your muscles/hand/body to continue accelerating the racquet through contact)
4. The timing and quality of contact on the stringbed

So by pure physics, you just increase all of the above. But in practice, you will see that some of the parameters above may cause some other parameters to degrade, affecting the end result. Which is why you should just ignore physics here, and just get to the court and practice.

For example, trying to do an enormous "racket head speed" (item 2 above) most probably would affect your quality of timing/contact (item 4), based on your skill level, leading to possibly an inverse effect.
Essentially if you try to increase ANY of the parameters above, without considering your skill level, it may adversely affect other items, leading to possibly a reduced quality on shot.
 
Morch Us said:
You may want to think a bit more about your question, if you are really talking about Physics here. "Power" ? Do you mean the velocity of the ball as it goes across the net ? Or the absolute energy on the ball as it hits the opponent racquet?
en.wikipedia.org

Kinetic energy - Wikipedia

en.wikipedia.org en.wikipedia.org
en.wikipedia.org

Momentum - Wikipedia

en.wikipedia.org en.wikipedia.org
www1.grc.nasa.gov

Newton’s Laws of Motion | Glenn Research Center | NASA

Sir Isaac Newton’s laws of motion explain the relationship between a physical object and the forces acting upon it. Understanding this information provides us with the basis of modern physics. What are Newton’s Laws of Motion? An object at rest remains at rest, and an object in motion remains in...
www1.grc.nasa.gov www1.grc.nasa.gov

My guess is that you are really talking about the velicity of the ball
In general, the instantanious velocity change on theball during contact is affected by
1. the mass of the racquet,
2. the instantatnious velocity of the racket
3. the force being applied on the racquet (by your muscles/hand/body to continue accelerating the racquet through contact)
4. The timing and quality of contact on the stringbed

So by pure physics, you just increase all of the above. But in practice, you will see that some of the parameters above may cause some other parameters to degrade, affecting the end result. Which is why you should just ignore physics here, and just get to the court and practice.

For example, trying to do an enormous "racket head speed" (item 2 above) most probably would affect your quality of timing/contact (item 4), based on your skill level, leading to possibly an inverse effect.
Essentially if you try to increase ANY of the parameters above, without considering your skill level, it may adversely affect other items, leading to possibly a reduced quality on shot.
Click to expand...
I attempted to make this point in post #3. But I think you did a more complete job here
 
HunterST said:
Obviously the weight of the racquet and the strings affect power also. But in terms of technique and what the player produces, is it all about racquet head speed? Or does the mass of the player come into play as well?

I feel like I get more power when I step into the ball, etc., but I'm not sure if that's just a way of creating more RHS, or if somehow it is adding energy mass.

Obviously it won't affect proper technique either way, but I think it would help to know the physics behind it.
Click to expand...
@HunterST has only posted the OP and has not been back.

This is another one of those threads where we argue over undefined tennis terms and those same words that have been defined for use in science.

There are some interesting arguments. @Dragy and I have different points of view over linear vs circular drives. That needs some studies of pro tennis players that I would be interested in but am probably not going to start and do. It is an important question that probably is not known or measured in 2024 - percentage of pros that prefer circular vs linear forehands?

Anyhow, if you want to argue over terms, like power, then argue over terms that are defined for some scientific subject and not over completely undefined terms as nearly all tennis terms are. Often you cannot Google the meaning of tennis terms. AI might increase the use of undefined tennis terms and make things worse regarding True vs False. ?
 
Last edited:
Here is a reference review on the forehand and its many variations from 2013.

It has some studies and statistics of what is being done.

Mechanics and Learning Practices Associated with the Tennis Forehand: A Review - PMC

The forehand ranks closely behind the serve in importance in the sport of tennis. Yet, while the serve has been the focus of a litany of research reviews, the literature describing forehand stroke production has not been reviewed as extensively. The ...
www.ncbi.nlm.nih.gov www.ncbi.nlm.nih.gov
 
Dragy said:
Yeah that's very easy to see. Whenever they get an easier, shorter ball, they use neutral stance and hit with forward shift. Whenever they face pushing, heavy, rising ball, they use open stance and stay more in place (still you can see forward head movement even though most transfer is lateral). I wonder how you cannot see it with your love to videos?

VhEzAEw.png


But the most important thing is all variations - neutral, open, semi-open, with more forward shift, with more upward lift and twist in place, even with backwards shift - all are important and applied situationally. There's no some single mythic ideal way of hitting a forehand. If any, it's how they hit a sitter from the baseline - and it's typically semi-open stance, diagonal weight shift, fade drive.
Click to expand...

My standard for a circular forehand follows Dan Brown's description and the video "I'm on Your Side Tennis" Forehand Youtube.

I simply use that if the head moves forward during the forehand much less then a step - it is a circular forehand. I also disregard running or stepping toward the ball for positioning.

Here is a compilation of forehands. I find nearly all are circular and not step-forward-weight-shift forehands. (See Dan Brown video for many details)
 
Last edited:
You must log in or register to reply here.

Similar threads

J
Technique all about raquet head speed?
2
Replies
63
Views
2K
SystemicAnomaly
SystemicAnomaly
P
Physics of ball velocity: Racquet speed versus acceleration?
2
Replies
73
Views
12K
SystemicAnomaly
SystemicAnomaly
T
Serve speed physics question thingamajig
Replies
20
Views
1K
travlerajm
travlerajm
R
Is perfect technique = power/racquet head speed?
Replies
16
Views
2K
wannabe good
W
L
Question about speed
Replies
12
Views
1K
dman72
D
Back
Top