Kinematic Graphs Of PGA Pros - Which one is the caster all the way from top of backswing?

[WILDTHING]

Golf instruction on 'How' is an art while the biomechanics 'stuff' is a 'What'. Biomechanics in itself might be able to determine the differences in the kinematics/kinetics between pros and recreational golfers but it cannot teach a recreational golfer how to swing like a pro.

If a golf instructor has done his job properly , he would assess your capabilities and then decide what might work best for you although there is a risk he could be leading you down a crooked path.

If I was offered a golf lesson and the instructor said I need to teach you 'stack and tilt' , I think I have enough knowledge to decide not to use him . Not because I don't think its a valid swing technique (it is) but I know it will cause my specific body damage .

Further , if the golf instructor was going to teach me a technique to actively use my wrists in the downswing , I'd probably decline. Or if the golf instructor said he was going to teach me a body swing with passive arms , I'd probably go elsewhere.

I know I cannot swing like a Tour pro and I'll probably end up with an arm swing (with a reactive pivot) than a pivot driven one (ie. with dynamic x-factors built in). When I say reactive pivot , I don't mean that it doesn't follow the kinematic sequence. It will still be Pelvis/Ribcage/Arm/Club but there won't be some stretch-shorten x-factor between my pelvis & torso or torso & shoulder girdle. I'll probably be using only my shoulder girdle muscles to create clubhead speed (with some x-factor between the shoulder girdle and wrists) in the early downswing before release and some ground reaction forces to get my body out of the way of my swinging arms.

 

[rocullen]

Golf instruction on 'How' is an art while the biomechanics 'stuff' is a 'What'. Biomechanics in itself might be able to determine the differences in the kinematics/kinetics between pros and recreational golfers but it cannot teach a recreational golfer how to swing like a pro.

Yeah, if an instructor grabbed your hips and said they have to turn like this, the golfer could figure out what needs to be done to get the hips to turn that way. Most, not all, could read til they pass out and not understand the "talk" or know how to go about doing it.

If a golf instructor has done his job properly , he would assess your capabilities and then decide what might work best for you although there is a risk he could be leading you down a crooked path.

If I was offered a golf lesson and the instructor said I need to teach you 'stack and tilt' , I think I have enough knowledge to decide not to use him . Not because I don't think its a valid swing technique (it is) but I know it will cause my specific body damage .

Further , if the golf instructor was going to teach me a technique to actively use my wrists in the downswing , I'd probably decline. Or if the golf instructor said he was going to teach me a body swing with passive arms , I'd probably go elsewhere.

Agree. All an instructor can do is do what he thinks is right. May not be.
I played for decades(off and on) with a baking soda approach(Arm and Hammer(hands) that the more I "think" passive hands the better I hit the ball. I know they're still there and do their part, but I don't try any actuation with them.

I know I cannot swing like a Tour pro and I'll probably end up with an arm swing (with a reactive pivot) than a pivot driven one (ie. with dynamic x-factors built in). When I say reactive pivot , I don't mean that it doesn't follow the kinematic sequence. It will still be Pelvis/Ribcage/Arm/Club but there won't be some stretch-shorten x-factor between my pelvis & torso or torso & shoulder girdle. I'll probably be using only my shoulder girdle muscles to create clubhead speed (with some x-factor between the shoulder girdle and wrists) in the early downswing before release and some ground reaction forces to get my body out of the way of my swinging arms.

Unfortunately, I'm leaning that direction, although I found a "drill" today to help. Grip the club as normal, take bottom hand off and grab the hosel. Swing that a few times and I can achieve a feel I can fairly often reproduce and I have incorporated a fairly level hip turn to start down swing.
Now all I need is a few more elements.

 

[WILDTHING]

While delving into Kinematic sequence graphs I also found this research article that amalgamates all the research done using 'Electromyography' of the main muscles used in the golf swing. This is the best information I could find that provides some scientifically measured data rather than opinion . Note that 'Electromyography' measures eccentric and concentric muscles contractions but cannot measure isometric muscle contractions (ie. remember that 'Bullworker' strength device)

799.full.pdf (bmj.com)

Electromyography (EMG) measures muscle response or electrical activity in response to a nerve's stimulation of the muscle. During the test, one or more small needles (also called electrodes) are inserted through the skin into the muscle. The MMT (Manual Muscle Testing) percentages provide a measure on the degree of muscle contraction

So while I had some spare time I decided to post some pictures of the muscles that are mainly used in the the golf swing . I couldn't be bothered to do the muscle images of the follow-through but I've mentioned whether it's the LEFT or RIGHT muscle being contracted. This might be useful for future reference if we get into debates about which muscles might need to be trained/developed in a golf swing.

1. Backswing
2. Forward Swing (from top of backswing P4 to club shaft horizontal P6)
3. Acceleration (from club shaft horizontal P6 to impact P7)



BACKSWING



FORWARD SWING



ACCELERATION




One thing I noticed for the early downswing stage (P4-P6) is there's lots of lower and upper body muscle contractions but very little used in the mid-section of the torso.

In the later downswing stage (P6-P7) there is still a lot of upper and lower body muscle contractions but the right oblique gets more involved.

I can only assume that for most of the downswing the legs are primarily responsible for turning the ribcage , while there is also some assistance from the right oblique.

 

[WILDTHING]

On reflection , I think that from transition to left arm horizontal (P5) in the downswing , there is an isometric contraction of the obliques as the pelvis rotates, and then they are actively concentrically contracted from P5 -Impact (P7). But I need to double check this.

The video below shows how the obliques could be used to rotate the ribcage/spine.

0:25 -0:28 would be a more isometric contraction
0:31- 0.:33 would be the concentric contraction




Tyler Ferrell suggests an active concentric contraction from transition but I think that might not be wholly accurate.

 

[WILDTHING]

I checked this out with Dr Mann and he says

"I don't think that a golfer should worry about the type and degree of muscular contraction of the abdominal obliques that are happening between P4 => P5.5 because there is a huge variability depending on whether one has hula hula flexibility and depending on whether one has a tendency to generate dynamic X factor stretch during the transition. I have zero hula hula flexibility and most of the muscle power to rotate my body comes from the use of my pelvic girdle muscles, which causes my pelvis and upper torso to rotate as an unit. I am sure that my abdominal oblique muscles are also contracting at the same time, but I do not need to know whether they are contracting isometrically or isotonically, concentrically or eccentrically. If a golfer has a lot of hula hula flexibility, the pelvis can out-run the upper torso so he may need to contract his abdominal oblique muscles sooner and more powerfully. However, he only needs to think of the timing of his upper torso rotary motion, and he does not need to know which muscles are involved in the biomechanical event. "

"A golfer who has a lot of hula hula flexibility (which is a term that I use to describe a high degree of flexibility of the lumbar spine zone that can allow a golfer to rotate his pelvis independently without simultaneously rotating his mid-upper torso - as seen in hula hula dancers) can potentially rotate his pelvis so fast between P4 => P6 that the mid-upper torso cannot keep up from a rotational perspective. Under those non-optimum conditions, the golfer will develop an excessive amount of torso-pelvic separation, where the upper torso/arms are too far back (relative to the pelvis) at the ~P5.5 position. That biomechanical predicament can potentially result in two different non-optimum pivot motion events that can resultantly happen between P5.5 => P7. The first resultant possibility that can happen if the pelvis out-races the mid-upper torso between P4 => P5.5 is that the upper torso/arms "hang back" far too much and the golfer will then approach impact with his clubshaft angled far back behind his hands, which can repeatedly result in push-sliced shots. The second resultant possibility is that the golfer will unconsciously try to compensate for his excessive degree of torso-pelvic separation by activating his right-sided mid-upper torso muscles during his mid-downswing, and that can produce an "OTT move" type of golf swing action that happens in the mid-downswing (and not at the very start of the early downswing). This mid-downswing variant of the "OTT move" type of golf swing action will produce a "tumble action" where the golfer "tumbles" the clubshaft over the swingplane during his mid-downswing time period, thereby resulting in an undesirable out-to-in clubhead path through impact. "

 

[wadesworld]

Maybe a kinematic sequence graph of your own swing compared to PGA tour pros could help identify areas to make your swing more efficient (ie. more clubhead speed with less effort) . However there is no guarantee that a perfect kinematic sequence will make you a better player but 60% (a high percentage) of all pga pros use the pelvis/ribcage/arm/club in their swing biomechanics.

I've obviously got no direct experience, but my understanding is the vast majority of PGA Tour pros do not spend their time in such minutia. They swing the club. Their teachers are VERY careful about making changes to their natural move. It's more tweaks than changes.

I think an amateur golfer trying to pursue such minutia is more likely than not to wreck their swing.

 

[Lane]

Just curious - Please explain for me - what exactly do you mean by , “ lead hand “ ?

 

[rocullen]

the one "not" following. The target hand.

 

[WILDTHING]

I've obviously got no direct experience, but my understanding is the vast majority of PGA Tour pros do not spend their time in such minutia. They swing the club. Their teachers are VERY careful about making changes to their natural move. It's more tweaks than changes.

I think an amateur golfer trying to pursue such minutia is more likely than not to wreck their swing.

As I've mentioned before this is the 'What' going on in the swing , not the 'How'. I don't use any of these body thought moves when I swing and nor does Dr Sasho Mackenzie who is an expert in the kinetics of the golf swing (he actually uses external focus cues as per Dr Gabriele Wulf's research) . But if your trying to improve your technique, you need an appreciation of the 'What' before you start on the 'How' , but of course, its theoretical just like every golf instruction out there .

I disagree that PGA pros just swing the club because many (with the help of their instructors) are now using 3D systems , force plate technology , trackman to 'tweak' any changes. The problem arises when the instructors theorise what changes need to be made depending on their own ideas of cause and effect in the golf swing. Sometimes the changes make a positive difference while others can have a detrimental effect on their swings.

This is a good video (if you have the time to view it) that has given me a better idea of how muscles generate forces in the golf swing . So faster contracting muscles produces less force (something I've only just learned from this video).

 

[Lane]

Wow! This a bit of information to process. I appreciate the information. Gives me something to think about during boring conference calls

This a "Chicken wing" that has won 3 majors and 10s of millions of dollars.
At the end of the day, if it works, it works.

Jiffy pop- Wildtgin

Wow! This a bit of information to process. I appreciate the information. Gives me something to think about during boring conference calls

This a "Chicken wing" that has won 3 majors and 10s of millions of dollars.
At the end of the day, if it works, it works.

Wow! This a bit of information to process. I appreciate the information. Gives me something to think about during boring conference calls

This a "Chicken wing" that has won 3 majors and 10s of millions of dollars.
At the end of the day, if it works, it works.

Yes , his short game and putting seems to be a major (no pun intended) contributor to those wins.

69th ranked driving distance
186th ranked driving accuracy ( 54.29% )
23rd Eagles
8th Birdie Average
11th Scoring Average
7th Putts per round
118th Greens In Regulation

Wow! This a bit of information to process. I appreciate the information. Gives me something to think about during boring conference calls

This a "Chicken wing" that has won 3 majors and 10s of millions of dollars.
At the end of the day, if it works, it works.

Jiffypop - let’s just pause for a second and think about the suggestion someone made to Windthing that , “ the chicken wing helps keeps the clubface square ** POST ** impact !
HUH? —- wouldn’t that ONLY be made possible by keeping the clubface * square / facing the target * PRE - IMPACT ? AND - what is the ONLY part of the human body that can make this happen. This misinformation is prevalent in today’s golf instruction and , unfortunately, many never pause and use their own skills of deduction to reject such nonsense. They just follow the herd and that is a shame !

 

[Lane]

On reflection , I think that from transition to left arm horizontal (P5) in the downswing , there is an isometric contraction of the obliques as the pelvis rotates, and then they are actively concentrically contracted from P5 -Impact (P7). But I need to double check this.

The video below shows how the obliques could be used to rotate the ribcage/spine.

0:25 -0:28 would be a more isometric contraction
0:31- 0.:33 would be the concentric contraction




Tyler Ferrell suggests an active concentric contraction from transition but I think that might not be wholly accurate.

Protractions, reactions , infractions , contractions ( whatever ) . Simply more analytical analysis goobdelygook done to indicate how intelligent I am ! Humans are genetically designed so we don’t need to worry about how they work . We don’t need to think about how we walk, throw objects . We don’t need to think about the distance between our feet when we walk or run BC- the human body will always position itself to accommodate the path it’s dominant hands wish to travel And that is all a player needs to know to be successful at golf .
If you want to waste your time thinking about things which you HAVE NO CONTROL OVER that’s your prerogative !
You can’t change or alter the human genetics structure . Therefore, your only choice is to serve it and knowing what CONTROLS all those muscles is the ** key ** to a successful swing . All memory is stored in the brain and it sends signals to it extremities to perform task AND - those dummies ( puppets on a string ) will stretch and pull bones to form levers as they are instructed . They are not capable of remembering. Their is no such thing as * muscle memory *!

 

[WILDTHING]

Lane

Check out what I said in the opening post

"Not sure this would interest many of you who aren't into golf biomechanics "

I appreciate you prefer your own theories but I'm not really interested in human genetic structure and you are free to ignore this thread if you find it personally irrelevant.

 

[WILDTHING]

For those of you who want to learn more about the biomechanics and use those kinematic sequence graphs to help analyse what the golfer might be doing , then check this blog article by Dr Phil Cheetham.

Variations in the Downswing Kinematic Sequence of Golf: Stretching, Riding, Fanning - Dr Phil Cheetham

I may have been partially correct about a previous post comment made but only specific to some golfers who use 'Riding'.

"I think that from transition to left arm horizontal (P5) in the downswing there is an isometric contraction of the obliques as the pelvis rotates, and then they are actively concentrically contracted from P5 -Impact (P7). But I need to double check this. "

It seems that if a golfer's pelvis/torso graph lines (in the kinematic sequence) are 'Riding' on top of each other it suggests that the 'Core' muscles (not just the obliques) are in isometric contraction . Isometric contractions are able to create lots of tension in the Core muscles than could be utilised later in the downswing (say in the Release -Impact phase).

LPGA women can rotate their hips and ribcage faster (as individual segments) than PGA men, but that doesn't mean they are creating as much tension/force in their Core muscles as PGA men which can be utilised later in the golf swing to transfer energy from the Core to the arms/club.

Note what Dr Cheetham said in his blog below

"The stretching method in the downswing is more efficient than the riding method provided that the stretch is not too excessive or too slow."

LPGA women who have lots of flexibility between pelvis and torso can just stretch and stretch and stretch but still not create enough tension force in their Core muscles. Further, because the stretch is too slow this can disrupt the timing of their kinematic sequence in transition and early downswing and affect the efficiency of their 'Release'.

Here is Dr Phil Cheethams blog extract.
--------------------------------------------------------




Three methods of beginning the downswing kinematic sequence are explained; they are:

• Stretching: Proximal segment precedes the distal segment, stretching the muscles, putting them in eccentric contraction hence providing more force for later in the downswing.
• Riding: Proximal and distal segment turn at the same speed in the downswing, the muscles are in isometric contraction to stabilize the distal segment. Large force is built up between the segments also providing large initial force for later in the downswing.
• Fanning: Distal segment immediately precedes the proximal segment in the downswing with the muscles immediately going into concentric contraction not allowing as much force to build; not as effective at the other two methods.

These relationships can be explained by looking at the force-velocity curve of muscle contraction.

The key to an efficient transfer of energy in the downswing is a good kinematic sequence. Each body segment should accelerate and decelerate in an orderly sequential manner. But there is more to it than simply seeing the curves accelerate and decelerate. Look at the two downswing kinematic sequence graphs below; yes, it is obvious that the golfer on the right is out of sequence, the blue curve (the lead arm) peaks before the red (pelvis) and the green (thorax or upper body); whereas, the peaking order of the golfer on the left is correct; pelvis, thorax, arm then club.



There is another obvious difference between the two graphs and you can see from the captions, one is called “riding” and the other is called “fanning”. Riding is where all the curves track very closely together in the early phase of the downswing and fanning is where they fan apart. What does this mean and how does this effect efficiency? Unfortunately, the fanning method does not transfer energy as well as the riding method.

To simplify the discussion, let’s use graphs of just the pelvis and thorax sequences in the downswing. Remember that the kinematic sequence shows the turning or swinging speed of the segments. Let’s also add a third version called “Stretching”. Focus in on the area in the gray circle; this is the beginning of the downswing.

Examine the middle graph first; if the two curves rise very closely together then these two body segments are turning at about the same speed and accelerating at approximately the same rate (at least for the early portion of the downswing). That means there is no relative speed difference between the two body segments so the thorax is “riding” on the pelvis and the core muscles are in isometric contraction. Let’s look at this from a muscle biomechanics perspective. Check out the Force-Velocity Curve in the graph below.




Notice that when there is isometric contraction, force production in the muscle is very high, that is, the muscle is very capable of generating a large force in an isometric contraction. This is a classic example of energy transfer across a joint, in this case, the “joint” is lumbar and lower thoracic spine. The energy generated by the legs and butt gets the pelvis turning, and in the “riding” example, the core is strong enough to pass this energy (and speed) directly to the thorax. At the appropriate time the core muscles fire explosively, the thorax increases speed but the pelvis is pushed back. This opposite torque causes the pelvis to “peel” off and then decelerate. The riding method is a very efficient method of transferring and adding energy to the thorax.

Now look at the stretching example; here the pelvis is moving slightly faster than the thorax in the early part of downswing. This means that the spine angle is actually widening under eccentric contraction. The muscles are lengthening slightly so the force-velocity curve now shows that the muscle is capable of generating even more force than in the isometric condition. This is one physiological reason why it is beneficial to stretch the core in the downswing; it allows the muscles to produce more force and store energy which is returned and transferred to the thorax as soon as the muscles begin concentrically contracting.

So in summary so far; when the red curve is higher on the graph than the green curve, the pelvis is turning faster than the thorax and the core muscles are eccentrically contracting; this is the “stretching” example. In contrast, when the red and green curves are riding almost exactly on top of each other then the pelvis and thorax are turning at the same rate and the muscles are isometrically contracting; this is the “riding” example. The stretching method in the downswing is more efficient than the riding method provided that the stretch is not too excessive or too slow. This action is known as the stretch-shorten cycle of muscle. Both stretching and riding are better than the fanning method which is now to be discussed.

What happens in the “fanning” method and why is it not as efficient? Again look at the pelvis (red) and the thorax (green) curves in the graph. You see that pretty much immediately after the top of backswing, the thorax curve accelerates faster than the pelvis curve, consequently there quickly becomes a large speed difference between the two body segments and the muscles are immediately contracting concentrically. Looking at the force-velocity graph we see that we have dropped to a lower force on the curve. As speed increases the muscles cannot produce as much force. Certainly as the speed between segments increases even more the force a muscle can produce drops even more.

In short, research has shown that a pre-loaded muscle can contract more forcefully than one that is not pre-loaded. So both the stretching and the riding methods pre-load the muscle. It has also been proven that a quick pre-stretch of the muscle may produce an even more forceful contraction so an appropriately pre-stretched muscle will contract more forcefully than one that is not.

I have used the pelvis and thorax as the example here, but if you look at the first graph presented you can see that similar actions occur at each joint during the downswing. The shoulder and the wrist also undergo a similar eccentric, isometric or concentric contraction at different phases of the downswing. Looking at the shape of the kinematic sequence curves in the early downswing can give us insight in how powerful the downswing is likely to be; moderate stretching and riding are good, but fanning is not. Note that fanning at the wrist joint early in the downswing is also more commonly known as casting; using this analogy you could call fanning at the shoulder; casting the arm, and fanning at the spine as casting the thorax.

---------------------------------------------

 

[WILDTHING]

Here is another example where Dr Phil Cheetham was trying to analyse an LPGA players swing issues.

Saturday, December 12, 2009
Changing the Kinematic Sequence with Biofeedback Drills

I am currently working with an LPGA player to improve her efficiency in the kinematic sequence and get her more swing speed. Remember that the kinematic sequence is the graph of turning speed of pelvis (red), thorax (green), arm (blue) and club (brown). It is measured in degrees/second along the vertical axis and shows time through the swing along the horizontal axis. (Check my earlier blog articles for more detail or amm3d.com). After capturing her swing with the AMM3D golf motion capture system, I analyzed it with the TPI 3D biomechanics report. Below is the graph of her kinematic sequence with a driver. There are many “expert” characteristics in the graph; transition order is good, peaking order is good, accelerations and decelerations generally look good too.




Although she transitions in the correct order; pelvis, thorax, arm, club; you can see that she pauses with her hips before transition (the red curve flattens out), also her transition period is too long, there is minimal downswing loading of any joint and her turning speeds are fanning early in the downswing. This pause really limits the speed contribution of the “stretch-shorten cycle” of the muscles. In an ideal stretch-shorten cycle there should be virtually no time between the eccentric/concentric contraction phases of the muscle; this “amortization” phase or pause should be as short as possible. The lack of downswing joint loading means she is leaving a lot of power on the table and the fanning of the curves means that the relative speed between the body segments is increasing, reducing the amount of force that can be produced in each muscle; (see my article on amm3d.com regarding Riding, Stretching, Fanning, I’ll post it soon on this blog too).

So while she was still in the AMM3D system we began using real-time audio biofeedback to see if we could change the sequence and teach her not to pause at the top; hence allowing the smooth acceleration into and out of transition and improving the stretch-shorten cycle. We set the audio tone to sound if she achieved a good core stretch at the beginning of downswing and worked on half backswing drills. Very quickly she was able to coordinate her downswing loading (aka “X-Factor Stretch”) and the curves became smoother before and after transition. We also saw that thorax, arm and shaft “rode” up together (good energy transfer); however, her total transition time was still very long. This means that the drill was definitely successful but that we still need to work on lessening the transition time from about 0.17 seconds to about 0.8 seconds. This will require a combination of half swing drills and strengthening of the core muscles so they can support fast pelvis firing without leaving the thorax behind. Check out the kinematic sequence graph below, this is from one of the half swing drills.



Drills can definitely change the kinematic sequence very quickly, but conditioning exercises will also need to be done in the gym to support the change. The trick will be to transfer this to the full swing.

-------------------------------------------------------

 

[WILDTHING]

I would throw in there that it is difficult to isolate any stretch-shortening effects from how the timing of when each subsequently more distal segment starts to speed up (and those effects). From a momentum transfer-perspective, it is this timing that is essential to the final speed at the most distal end. Any ‘slack’ can have effects on both timing and force/torque output, and duration, in more proximal segments.

I’ve seen folks emphasize things like the X-factor concept and not understand how their efforts influence leg outputs (turning the pelvis) and timing of subsequent segments.

There is a research article that did a lot of measurements of kinematic data between LPGA vs PGA and here is a comparison of the results.



The PGA men had slightly better peak trunk rotational velocity and that might partially explain why their driving distances are superior to LPGA women.

But look at the left and right wrist peak angular velocities and how quickly the PGA men's right elbow straightened.

So is there another partial reason to explain PGA superior clubhead speed other than an optimally timed kinematic sequence and x-factor stretch? Maybe it relates to how quickly the left wrist uncocks and how quickly the right wrist moves from extension in the flexion direction. That seems to suggest that LPGA women can't release their wrists as efficiently as men or maybe find it more difficult to hold the lag angle and are releasing earlier in the downswing. However , am still unsure how the rapid straightening of the elbow might affect clubhead speed.

The research article does point to the fact that LPGA women suffer twice as many injuries to their lead wrist compared to PGA men.

Still a bit of a mystery to be honest .

 

[WILDTHING]

I'll chew on the numbers more, but to me the torso rotation is the big one....
My understanding of the chart is they are only looking at angular rotation. There are linear aspects that are not captured in the chart. Linear components may be small for the pelvis and torso, but their contributions (to speed at the club head) increase as you move down to the other segments and ultimately the club head.

To my eye, torso rotation, while not significantly different at some p-value (the range of swings you mention above lead to enough variance), is still the essential piece. When coupled with, on average, longer levers (starting with shoulder width and continuing out to the clubhead) and the linear components, men are going to generate faster clubhead speed. Small differences in torso rotation will be magnified at the clubhead.

The analogy has its flaws, but imagine a whip made of segments. If you measured rotation rates of each segment you might end up with data like above. But if you look at the linear components (instantaneous) near the handle versus those at the tip you'll see large differences in speed.

And if you've ever cracked a whip, you quickly see how timing is everything and small movements at the handle (pelvis-torso on the golf swing) can influence whether the tip reaches the speed of sound.

Does that make sense?

I can understand (for example) when an ice-skater is spinning with their arms stretched horizontal that if you measured the speed of their hands it would be greater than when they brought their arms closer to their body . That although the body ends up rotating faster , their hands are moving at a slower speed . So yes , the LPGA players could theoretically be rotating quicker than PGA men but because their arms are shorter, their hand speed could still be inferior. The fact that PGA men are rotating their trunks quicker than LPGA might show up as a significant increase in their hand speed.

Not sure I understand what you mean by linear components but the research article link is below (you can download the pdf if you wish -its free)

(PDF) Swing Kinematics for Male and Female Pro Golfers (researchgate.net)

 

[WILDTHING]

Regarding linear components, I’ll have a look at the paper and see how they measure stuff when I get a chance. I’m just thinking about actual movement- how is it rotating relative to some reference point and is displacement relative to some point also happening. Rotational information might not capture how an end part is moving relative to something (like the ball). Those curvilinear paths are not made up of just angular movement.

For example, I could hold a pen with one arm and 7-iron with the other, both arms straight.
I then perform a curl and some maximum angular velocity (degrees per second) is reached while doing it.
Let’s say the maximum angular velocity is the same for both the arm+pen and the arm+7-iron.
While max angular velocity is the same, the speed (along the curved path) of the pen point and clubhead are very different.
Two people (one short, one tall) could have similar angular rotations of a bunch of body parts but due to their different sizes (like shoulder width, upper arm, and forearm) the clubhead could be moving at different speeds.

In a segmental system, small differences in proximal segments (like size or velocity) can lead to larger differences later due to additive effects. The data in the chart are consistent with that.

Yes , I see what you mean . I don't think the research article will provide body segment measurements but we do get shorter PGA men who can still bomb the driver more than LPGA women . Pity we don't have the data for those scenarios (ie. short PGA men kinematics versus tall LPGA women).

There is another possibility for the PGA superior driving distances and that could be the 'In Plane MOF' they generate is higher than LPGA (I'll post an image soon to describe what I mean).

Does this image provide a possible reason? Could PGA men be able to create superior ground force reactions to extend their lead side more powerfully than LPGA women? Apologies but I've used some TGM terminology like PP1 in the image (I'll attach another image to make that clearer).




Here is PP1 pressure force (the yellow region 'Pressure point #1' ).

 

[blugold]

Yes , I see what you mean . I don't think the research article will provide body segment measurements but we do get shorter PGA men who can still bomb the driver more than LPGA women . Pity we don't have the data for those scenarios (ie. short PGA men kinematics versus tall LPGA women).

There is another possibility for the PGA superior driving distances and that could be the 'In Plane MOF' they generate is higher than LPGA (I'll post an image soon to describe what I mean).

Does this image provide a possible reason? Could PGA men be able to create superior ground force reactions to extend their lead side more powerfully than LPGA women?

I think the reason why PGA tour players are better at creating swing speed than LPGA professionals.

Swing speed isn't just about angles and mechanics. There's a genetic predisposition to dynamic movement that is not coachable or trainable at play here.

 

[WILDTHING]

I think the reason why PGA tour players are better at creating swing speed than LPGA professionals.

Swing speed isn't just about angles and mechanics. There's a genetic predisposition to dynamic movement that is not coachable or trainable at play here.

The mystery is that the measurements show LPGA women rotate their arms, pelvis and sometimes even their upper torso faster than PGA men but still create significantly less clubhead speed.

Here is an article from Monte Scheinblum and he is using the kinematic sequence to explain how clubhead speed is optimised.

Faster Hips do NOT Create Club Head Speed · Rebellion Golf

But the problem here is that there isn't much difference between the kinematic sequences of LPGA vs PGA (their rhythm and timing are very good) so there must be other reasons to explain why PGA men can create so much more clubhead speed. The data seems to suggest something to do with the left and right wrists and the right arm straightening, yet we know that there is very little active wrist torques being applied in the golf swing (they are relatively passive).

MIG could be correct about the generation of linear forces being a reason for PGA superior clubhead speed.

 

[pattyboy21]

Nick Faldo said he would use a chicken-wing swing if he absolutely HAD to hit a fairway or green on a particular shot. https://www.golftipsmag.com/instruc...he chicken swing is a,Cook by a single stroke.

 

[Desmond]

Just saw this thread - I can't devote the time it requires and we are all different. Thx for the posts.

My instructor, whom I pay and tells me not to look at youtube or golf forums for instruction (lol), tells me to start releasing from the top. He also tells me to feel as if the clubhead is the last part that starts moving. To me, that means the active movement of the lower, then upper body gets the club going, slowly at first, and then faster, building momentum and then the arms going as fast as you want or can, to make a swing at the ball and drive it.

 

[WILDTHING]

But nothing is cut and dry in golf biomechanics . We have a lot of support for the Kinematic sequence and X-factor stretch as per Dr Phil Cheetham's research but check this research article by Anderson (2007) who used 500 golfers with an handicap of 5 or less . I haven't read all 149 pages (yet ) but the conclusion does not support Phil Cheetham's kinematic proximal-distal sequence pattern.

---------------------
The 'Conclusion' on page 143 did not follow a Proximal-Distal order in angular kinematics, kinetic energy or angular momentum. The only connection point to show a consistent delay in peaks between neighbouring segments was the wrist, or the interface between arms and club segments.

That the Arm angular momentum peaks before all other segments and it is unlikely that the Arms segment receives an angular momentum transfer from either the torso or hip segments in the downswing.

www.yumpu.com/en/document/read/10580132/anderson-speed-generation-in-the-golf-swing-thesis

Found a copy of the pdf at this link below

.item (bac-lac.gc.ca)

Back to square one!!!

 

[rocullen]

But nothing is cut and dry in golf biomechanics . We have a lot of support for the Kinematic sequence and X-factor stretch as per Dr Phil Cheetham's research but check this research article by Anderson (2007) who used 500 golfers with an handicap of 5 or less . I haven't read all 149 pages (yet ) but the conclusion does not support Phil Cheetham's kinematic proximal-distal sequence pattern.

---------------------
The 'Conclusion' on page 143 did not follow a Proximal-Distal order in angular kinematics, kinetic energy or angular momentum. The only connection point to show a consistent delay in peaks between neighbouring segments was the wrist, or the interface between arms and club segments.

That the Arm angular momentum peaks before all other segments and it is unlikely that the Arms segment receives an angular momentum transfer from either the torso or hip segments in the downswing.

www.yumpu.com/en/document/read/10580132/anderson-speed-generation-in-the-golf-swing-thesis

Found a copy of the pdf at this link below

.item (bac-lac.gc.ca)

Back to square one!!!

I will state up front that I am no physicist or know anything about bio mechanics. The posters carrying this discussion at the moment probably know that all to well.
But, I have a hard time believing that a body/object already in motion isn't sped up by a new force more than that force application to a motionless object.
Unless the thesis implies that the arms can only go "so fast"

I know when I have a good lower body rotation, the ball goes farther than when I don't. When practicing into a net there is also a louder "pop".

 

[WILDTHING]

I will state up front that I am no physicist or know anything about bio mechanics. The posters carrying this discussion at the moment probably know that all to well.
But, I have a hard time believing that a body/object already in motion isn't sped up by a new force more than that force application to a motionless object.
Unless the thesis implies that the arms can only go "so fast"

I know when I have a good lower body rotation, the ball goes farther than when I don't. When practicing into a net there is also a louder "pop".

That Anderson research paper is difficult for me to understand but I think the author is saying the following:

The golf swing doesn't follow the analogy of a bullwhip . That is where the segments in the direction from handle to tip passes energy and momentum to its neighbouring segment until you get incredible speed at the tip (faster than the speed of sound which is why you hear that crack). In Dr Phil Cheetham's research he is claiming the golf swing does follow that analogy , from hips -> torso-> arm -> club , optimally using x-factor stretches in the downswing. Anderson is claiming that the results show that the golf swing is more like a double pendulum where the 1st segment is the ' hips/torso/arm' all moving together as one unit , while the club is the 2nd segment.

In the analogy of a bullwhip which uses 'Proximal-Distal' type kinematics (movements) each neighbouring segment has smaller 'volume/mass/length' . The centre of mass of each neighbouring segment gets closer to the 'connection' (joint) of the preceding segment but the golf swing is different because the distal segment is the 'hand and club clamped together' which , although having less mass/volume than the arm (its neighbouring preceding segment), is longer and has its COM further away from the wrist joint (making its MOI - moment of inertia - its resistance to rotation) larger.

When you throw something , it does follow the 'Proximal -Distal' kinematic sequence . Your lower body from 'legs->hips' can be assumed to be the larger segment , then torso the 2nd segment , arm the 3rd segment , hand being the most distal 4th segment. Energy is transferred through those segments to the hand just like a bullwhip but in the golf swing the 'hand equivalent segment' (as seen in the throwing action) is replaced by the 'hand/club' unit which is longer and whose COM is further away from the wrist joint (than in the throwing action) . It follows that the kinematics may not follow the 'Proximal-Distal' sequencing advocated by Dr Phil Cheetham and the results of Anderson's research seems to prove it .

Hope that makes sense because the physics/maths in that research paper was too much for my brain to handle (stamina wise as well as intellectual).


In summary the 'general' golf swing kinetics for generating speed is quite simple and follows the description of 'Rod White' (a New Zealand Physicist).

"The golfer initially holds the club close to the body using wrist cock, and works very hard to build up the kinetic energy in the body and arms. The golfer then allows the club to swing away from the body, so the body and arms slow down and the club speeds up. I emphasise the term “allows”, because it can be an entirely passive process; the golfer does not have to make the club swing out – it happens naturally. "

The only transfer of energy is from the rotating 'hips/body/arms' (viewed generally as a single unit) via tension in the shaft to the clubhead , its not from 'legs/hips' -> torso -> arm -> club.

Obviously, the detailed golf swing biomechanics is far more complex as it involves describing the body movements and forces generated (via the hands on the club) to optimise the golf swing . The Proximal-Distal sequencing concept promoted by Dr Phil Cheetham or this alternative conclusion from Anderson doesn't provide any information on how the golfer squares the clubface by impact.

 

[DataDude]

Aaaaaand I just went cross-eyed

Yep, mine are stuck and I learned nothing. Have no clue what I'm looking at LOL!