70% of speed from hands? Where does this idea come from?

[iacas]

22 hours ago, Nels55 said:

Overall strength including arm strength is the difference.  My point is that women do not and cannot generate the same ground force peaks that men do.  And this is not because their arms are weaker.  Am I wrong about that?

 

Yes, because as I said, the GRF that women can generate versus the GRF that men can generate is well down on the list of reasons why men generally swing faster.

 

Also, remember what the "R" in "GRF" stands for. Men can, from their knees, swing faster with their arms and hands and a little torso turn than women, and that doesn't use a "lot" of GRF (except the obvious shear forces to resist spinning, like you would on ice).

 

Edited June 2 by iacas

[Dewdman42]

The concept of GRP gets over used and leads to misconceptions about it.  It’s an equal and opposite reaction to forces coming at it.  Their weight caused by gravity has nothing to do with club head speed as their mass and weight basically causes an equal and opposite reactionary force from the ground that simply prevents them from falling to the middle of the earth.  However the muscles are able to expend calories and generate new additional forces, a complicated topic in its own and this is where men can potentially generate the additional club head speed from.  But using muscles and biomechanics efficiently to transfer muscle output into club head speed is not an automatic given.  
 

there is possibly something to be said for inertia having a role, as a player moves their hands and shoulders and even the hip shift, these things involve mass being moved, which carries inertia.  If that inertia is directed into the ground or into the club head in the right ways through certain bio mechanical movement patterns it may be possible that men have more mass and more inertia which can be harvested, but only if that inertia is transferred to the club head ultimately.  
 

imho the use of GRF is simply a deflection device that can take some of the inertia and muscle output that moves towards the ground and deflects back through the body with proper bio mechanics to the club head.  Some of our muscle output and interia is already going directly to the club head, but the nature of our muscles is that they generally need something to push against in order to create new movement and inertia.  So we talk about GRF because ultimately that is what our body has available to push against and we need to use complex interactions in our body to use the ground to push against it and generate inertias that will end up directed into the back of the golf ball.  Simple as that, size and mass have little to do with it other then perhaps greater inertia of bigger and heavier moving body parts.  Greater muscle output, however, is a real thing.  Not only that but men also have different bone structures which can relate to the way bio mechanical interactions are carried out.

Edited June 2 by Dewdman42

[Nels55]

15 hours ago, iacas said:

 

Yes, because as I said, the GRF that women can generate versus the GRF that men can generate is well down on the list of reasons why men generally swing faster.

 

Also, remember what the "R" in "GRF" stands for. Men can, from their knees, swing faster with their arms and hands and a little torso turn than women, and that doesn't use a "lot" of GRF (except the obvious shear forces to resist spinning, like you would on ice).

 

I don't understand what you are trying to say here.  Ground reaction force measurement correlates directly with clubhead speed based on the data that I have seen.  The three measured peak forces occurring in the correct sequence at the right moment are the indication of an elite swing.  In the case of an elite swing the higher the measured ground forces the faster the clubhead goes.  Long drive specialists have the highest three peaks and hit the ball the farthest. 

[iacas]

6 hours ago, Nels55 said:

I don't understand what you are trying to say here.  Ground reaction force measurement correlates directly with clubhead speed based on the data that I have seen.  The three measured peak forces occurring in the correct sequence at the right moment are the indication of an elite swing.  In the case of an elite swing the higher the measured ground forces the faster the clubhead goes.  Long drive specialists have the highest three peaks and hit the ball the farthest. 

 

That's like saying that clubhead speed correlates to driving distance.

 

If you're going to have a player generate more clubhead speed, specifically working on "increasing their GRF" is probably well down on the list of things to do. You typically do other things… and let the GRF tick up a bit as a result.

 

Specifically working on GRF stuff is typically not in the top three.

 

Edited June 2 by iacas

[MonteScheinblum]

36 minutes ago, iacas said:

 

That's like saying that clubhead speed correlates to driving distance.

 

If you're going to have a player generate more clubhead speed, specifically working on "increasing their GRF" is probably well down on the list of things to do. You typically do other things… and let the GRF tick up a bit as a result.

 

Specifically working on GRF stuff is typically not in the top three.

 

Everyone knows holding lag is #1.

[MK7Golf21]

20 minutes ago, MonteScheinblum said:

Everyone knows holding lag is #1.

I thought it was eating a bag of skittles. 

[Shilgy]

14 minutes ago, MonteScheinblum said:

Everyone knows holding lag is #1.

Whenever I really want to bust one I start down slowly so I can hold that angle and then jump as high as I can at impact.

 

Is that not ideal?🤔

[Nels55]

1 hour ago, iacas said:

 

That's like saying that clubhead speed correlates to driving distance.

 

If you're going to have a player generate more clubhead speed, specifically working on "increasing their GRF" is probably well down on the list of things to do. You typically do other things… and let the GRF tick up a bit as a result.

 

Specifically working on GRF stuff is typically not in the top three.

 

Okay, I see what you are getting at.  I was not intending to say anything about what to work on to improve speed but I have seen a number of videos where Mike Adams, Terry Rowles, Dr. Scott Lynn along with some others do focus on GRF with students so I guess that it depends on the teacher and the student.  Hmmm, also it comes to mind that I lessons with a pro who had a really early GRF measuring device along with Flightscope and video and he said that the GRF measurement system was his number one tool for helping students.  In the end it really doesn't matter as long as the student gets better.

 

[GoTime]

1 hour ago, iacas said:

 

That's like saying that clubhead speed correlates to driving distance.

 

If you're going to have a player generate more clubhead speed, specifically working on "increasing their GRF" is probably well down on the list of things to do. You typically do other things… and let the GRF tick up a bit as a result.

 

Specifically working on GRF stuff is typically not in the top three.

 

 

What is the top three in your opinion?

[iacas]

6 minutes ago, Nels55 said:

Dr. Scott Lynn

 

The research director for SwingCatalyst does something with GRF in a video? 😄  FWIW, I've had a SwingCatalyst since 2013.

 

3 minutes ago, GoTime said:

What is the top three in your opinion?

 

Depends on the student. I'm just saying that directly working on GRF stuff is often not in the top three. Most people have a lot of lower hanging fruit than that, and increasing GRF stuff directly is often the final few percentage points.

[Soloman1]

and the reason you see them working on grf’s is because the player is already accomplished in swing speed, and it’s the last thing to do better for an incremental increase.

[Nels55]

16 minutes ago, Soloman1 said:

and the reason you see them working on grf’s is because the player is already accomplished in swing speed, and it’s the last thing to do better for an incremental increase.

This fellow works on grf with all of his students:

 

[Soloman1]

sigh, and he fixed other things first. getting to the lead side is more a positional than forces thing.

[johnrobison]

GRF in this case ends up being a result, not the thing being worked on. While grey, perhaps, it's possible to differentiate between sequencing as the goal, and GRF as the goal.

[iacas]

46 minutes ago, johnrobison said:

GRF in this case ends up being a result, not the thing being worked on. While grey, perhaps, it's possible to differentiate between sequencing as the goal, and GRF as the goal.

 

Yes. Virtually everything you do will change the GRF "graph" or "trace" or "arrows." That is different, to me, than working directly on those graphs/traces/arrows.

[Nels55]

43 minutes ago, johnrobison said:

GRF in this case ends up being a result, not the thing being worked on. While grey, perhaps, it's possible to differentiate between sequencing as the goal, and GRF as the goal.

Yes, I would say that everyone who knows what they are doing is teaching grf right from the start.  The pressure plates are simply a tool that can be useful in the right hands and may see more usage with some instructors then with others.  Possibly most or all instructors only use them with advanced students as @Soloman1 mentioned. 

[ferrispgm]

Just thinking out loud....I'm assuming grip strength would be a large limiting factor for female swing speed as well.

[betarhoalphadelta]

On 6/1/2024 at 12:57 AM, Soloman1 said:

it’s usually expressed as a percentage of mass. women usually don’t weigh as much, so force is less.

 

Not arguing with you, as I would REALLY like you to be right as a 250# dude... Then it just becomes improving my sequencing until I can unleash the inherent advantages that my prodigious mass gives me 😂

 

But if this is the case, I wonder why small guys like Rory can generate so much speed. Cam Champ who is 6'0" and listed at 175#. Kyle Berkshire who is pretty damn skinny. 

 

I'm sure they're also amazingly strong--I have seen Rory's numbers on Peloton and he's gotta have some VERY strong legs for a guy his size to be able to put up the outputs he's putting up. But then you'd think that the guys who are much heavier and who are ALSO very strong should be blasting it way past Rory. And yet they're not.

 

So I'm not sure that body mass is necessarily as big of an advantage as one might thing. 

 

As with most things, I'm happy to have someone explain why I'm wrong. 

[Shilgy]

30 minutes ago, betarhoalphadelta said:

 

Not arguing with you, as I would REALLY like you to be right as a 250# dude... Then it just becomes improving my sequencing until I can unleash the inherent advantages that my prodigious mass gives me 😂

 

But if this is the case, I wonder why small guys like Rory can generate so much speed. Cam Champ who is 6'0" and listed at 175#. Kyle Berkshire who is pretty damn skinny. 

 

I'm sure they're also amazingly strong--I have seen Rory's numbers on Peloton and he's gotta have some VERY strong legs for a guy his size to be able to put up the outputs he's putting up. But then you'd think that the guys who are much heavier and who are ALSO very strong should be blasting it way past Rory. And yet they're not.

 

So I'm not sure that body mass is necessarily as big of an advantage as one might thing. 

 

As with most things, I'm happy to have someone explain why I'm wrong. 

@MonteScheinblum has a few thoughts on my girth inertia idea but was reluctant to share them. 😎

 

 maybe you can convince him it’s for research.😂

[Soloman1]

38 minutes ago, betarhoalphadelta said:

 

Not arguing with you, as I would REALLY like you to be right as a 250# dude... Then it just becomes improving my sequencing until I can unleash the inherent advantages that my prodigious mass gives me 😂

 

But if this is the case, I wonder why small guys like Rory can generate so much speed. Cam Champ who is 6'0" and listed at 175#. Kyle Berkshire who is pretty damn skinny. 

 

I'm sure they're also amazingly strong--I have seen Rory's numbers on Peloton and he's gotta have some VERY strong legs for a guy his size to be able to put up the outputs he's putting up. But then you'd think that the guys who are much heavier and who are ALSO very strong should be blasting it way past Rory. And yet they're not.

 

So I'm not sure that body mass is necessarily as big of an advantage as one might thing. 

 

As with most things, I'm happy to have someone explain why I'm wrong. 

 

 

it was a general statement... 😉

 

increasing mass or acceleration has equal result. just because you're big doesn't mean you can accelerate quickly. rory's acceleration is big.

 

rory's speed is not tied to just grf. his core strength, general strength, balance and sequencing all contribute to it.

 

and the direction and timing of the force vector is important, not just the units/

[betarhoalphadelta]

14 minutes ago, Soloman1 said:

 

it was a general statement... 😉

 

increasing mass or acceleration has equal result. just because you're big doesn't mean you can accelerate quickly. rory's acceleration is big.

 

rory's speed is not tied to just grf. his core strength, general strength, balance and sequencing all contribute to it.

 

and the direction and timing of the force vector is important, not just the units/

 

LOL I get it. But if I look at the current top 5 on tour in driving distance and their "official" weights in their PGAT bios:

 

• Rory McIlroy 160 lbs:
• Cam Champ: 175 lbs
• Ben An: 240 lbs
• Kevin Dougherty: 180 lbs
• Wyndham Clark: 172 lbs

Now, every one of them but Rory is 6'0" or taller, suggesting longer levers might be useful. But only one is >200 lbs. 

 

To me, I think it has to do with the idea that being big has an advantage--you have stronger legs. But it has a corresponding disadvantage--you have a lot more mass those legs have to support. 

 

In a lot of the "golf fitness" threads on here, nobody says gain weight so you have higher GRF. They say work on leg strength (squats/glutes) and explosive leg strength (squat jumps/etc). It's not about your mass--it's about the strength to overcome your mass. 

 

As such, I don't think you can point to women having slower CHS because they're unable to generate the same ground forces because they're lighter than men. You could argue that it's because they generally have less leg strength in relation to their mass than men, but I don't think less mass in general is a relevant factor. 

[ThinkingPlus]

3 minutes ago, betarhoalphadelta said:

 

LOL I get it. But if I look at the current top 5 on tour in driving distance and their "official" weights in their PGAT bios:

 

• Rory McIlroy 160 lbs:
• Cam Champ: 175 lbs
• Ben An: 240 lbs
• Kevin Dougherty: 180 lbs
• Wyndham Clark: 172 lbs

Now, every one of them but Rory is 6'0" or taller, suggesting longer levers might be useful. But only one is >200 lbs. 

 

To me, I think it has to do with the idea that being big has an advantage--you have stronger legs. But it has a corresponding disadvantage--you have a lot more mass those legs have to support. 

 

In a lot of the "golf fitness" threads on here, nobody says gain weight so you have higher GRF. They say work on leg strength (squats/glutes) and explosive leg strength (squat jumps/etc). It's not about your mass--it's about the strength to overcome your mass. 

 

As such, I don't think you can point to women having slower CHS because they're unable to generate the same ground forces because they're lighter than men. You could argue that it's because they generally have less leg strength in relation to their mass than men, but I don't think less mass in general is a relevant factor. 

Actually I have mentioned extra body mass as a speed benefit. Specifically it increases the frictional force with the ground. You can also apply pressure into the ground to increase frictional force. Greater frictional force prevents slipping as one turns. Less slipping = higher potential speed.

 

BTW, when this was mentioned, everyone laughed so you have been warned.

[betarhoalphadelta]

10 minutes ago, ThinkingPlus said:

Actually I have mentioned extra body mass as a speed benefit. Specifically it increases the frictional force with the ground. You can also apply pressure into the ground to increase frictional force. Greater frictional force prevents slipping as one turns. Less slipping = higher potential speed.

 

BTW, when this was mentioned, everyone laughed so you have been warned.

 

Not going to laugh... I recall from another thread that you have a STEM background but admitted it's not MechE. I am an engineer, but an electrical engineer, so I am also STEM without direct expertise on this subject. 

 

I think the thing is that all that added mass also works to balance the increased friction though. 

 

Think of a go-kart. I'm 250#. I'm assuming you are significantly less. You and I are approaching a corner. If the added mass of friction gave me an advantage, I should be better able to corner than you. But the issue is that the force required to turn with me in the seat of a go-kart is a lot higher than the force required to turn with you in the seat of a go-kart. So even though I generate more friction due to my higher mass, I don't BENEFIT from that friction because I require more force to change direction. 

 

I would THINK that the same thing occurs in the golf swing. Perhaps as a much heavier individual I might have more ground force than someone who is lighter, but if that ground force is working against my much higher mass, the amount that can be transferred to the clubhead is the same as someone who has lower mass and roughly proportionately lower forces. 

[ThinkingPlus]

2 minutes ago, betarhoalphadelta said:

 

Not going to laugh... I recall from another thread that you have a STEM background but admitted it's not MechE. I am an engineer, but an electrical engineer, so I am also STEM without direct expertise on this subject. 

 

I think the thing is that all that added mass also works to balance the increased friction though. 

 

Think of a go-kart. I'm 250#. I'm assuming you are significantly less. You and I are approaching a corner. If the added mass of friction gave me an advantage, I should be better able to corner than you. But the issue is that the force required to turn with me in the seat of a go-kart is a lot higher than the force required to turn with you in the seat of a go-kart. So even though I generate more friction due to my higher mass, I don't BENEFIT from that friction because I require more force to change direction. 

 

I would THINK that the same thing occurs in the golf swing. Perhaps as a much heavier individual I might have more ground force than someone who is lighter, but if that ground force is working against my much higher mass, the amount that can be transferred to the clubhead is the same as someone who has lower mass and roughly proportionately lower forces. 

Bad analogy. If you were trying to slide your feet in a golf swing the frictional force would work against you. But you aren't. Your feet are planted and you are rotating against that stable base.

 

 

[ferrispgm]

This whole mass, increased friction, GRF stuff seems overplayed.  If you are a larger mass individual...chances are you are out of shape so inherently you won't be athletic enough to even make use of any benefits the increased weight may provide.  Also, if you are out of shape at 250, chances are your mobility would be limited as well.  Not many people on the planet are a natural 250 and athletic.  

 

I wonder how many of the elite pros generate high speeds because they use GRF properly or use GRF properly because they generate a lot of speed.  Like a lot of things, I think people in general want to be able to hit it as far as tour players and don't want to accept they genetically aren't able to generate the same speed....but the moment a new idea comes up that may have something to do with speed, that idea becomes the focus. I'm not saying GRF isn't a factor, but it's not THE KEY to speed.  So now everyone is trying to maximize their GRF, meanwhile their actual swing has not gotten any better or will get worse because their old GRF pattern was necessary to make decent contact.  

[GolfTurkey]

I guess it's worth noting that while we might marvel at guys like Rory for being so fast while resembling @ferrispgm's avatar, it's worth putting it in context.

 

He's fast for the PGA tour and extremely fast relative to the general civilian population. He hits it longer than some guys faster or the same speed as him because of optimal launch conditions (he's the high launch, low spin poster child on Tour). However, compared to the LD guys who are creeping up on 170 CHS he's not fast at all.

 

It's like marvelling at someone who runs the 100m in 12 seconds. Sure that guy decimates a bunch of slobs drinking beer around a BBQ, but in the greater scheme of pushing human limits it's a bit meh.

[Nels55]

1 hour ago, ferrispgm said:

This whole mass, increased friction, GRF stuff seems overplayed.  If you are a larger mass individual...chances are you are out of shape so inherently you won't be athletic enough to even make use of any benefits the increased weight may provide.  Also, if you are out of shape at 250, chances are your mobility would be limited as well.  Not many people on the planet are a natural 250 and athletic.  

 

I wonder how many of the elite pros generate high speeds because they use GRF properly or use GRF properly because they generate a lot of speed.  Like a lot of things, I think people in general want to be able to hit it as far as tour players and don't want to accept they genetically aren't able to generate the same speed....but the moment a new idea comes up that may have something to do with speed, that idea becomes the focus. I'm not saying GRF isn't a factor, but it's not THE KEY to speed.  So now everyone is trying to maximize their GRF, meanwhile their actual swing has not gotten any better or will get worse because their old GRF pattern was necessary to make decent contact.  

GRF a measurement that shows swing efficiency.  The peaks occurring in the correct sequence at the right moment mean an elite swing.  Having really high ground forces at the wrong time will not work.  Same as any other analysis tool when used correctly it will only improve a persons golf swing.  

[mgoblue83]

3 hours ago, betarhoalphadelta said:

 

LOL I get it. But if I look at the current top 5 on tour in driving distance and their "official" weights in their PGAT bios:

 

• Rory McIlroy 160 lbs:
• Cam Champ: 175 lbs
• Ben An: 240 lbs
• Kevin Dougherty: 180 lbs
• Wyndham Clark: 172 lbs

Now, every one of them but Rory is 6'0" or taller, suggesting longer levers might be useful. But only one is >200 lbs. 

 

To me, I think it has to do with the idea that being big has an advantage--you have stronger legs. But it has a corresponding disadvantage--you have a lot more mass those legs have to support. 

 

In a lot of the "golf fitness" threads on here, nobody says gain weight so you have higher GRF. They say work on leg strength (squats/glutes) and explosive leg strength (squat jumps/etc). It's not about your mass--it's about the strength to overcome your mass. 

 

As such, I don't think you can point to women having slower CHS because they're unable to generate the same ground forces because they're lighter than men. You could argue that it's because they generally have less leg strength in relation to their mass than men, but I don't think less mass in general is a relevant factor. 

Now display the same stats for long drive competitors.

 

Guessing most of them are 6’3”+ and

well over 200lbs.

 

There are levels to everything but PGA tour players have been getting taller, stronger and more athletic since Tiger came out.

 

I’ll repeat what I said earlier in this thread that @ferrispgm just mentioned again:

 

Mass, strength, explosiveness, rotation, ground forces, sequencing on and on are great but without enough hand and arm strength you cannot transfer the forces into the ball. It’s the #1 limiting factor for speed in my opinion. The guys you listed are not big by any stretch of the imagination but I guarantee you they have incredible grip strength. Like effortlessly crush your hand in a handshake type strength.

[MonteScheinblum]

3 hours ago, mgoblue83 said:

Now display the same stats for long drive competitors.

 

Guessing most of them are 6’3”+ and

well over 200lbs.

 

There are levels to everything but PGA tour players have been getting taller, stronger and more athletic since Tiger came out.

 

I’ll repeat what I said earlier in this thread that @ferrispgm just mentioned again:

 

Mass, strength, explosiveness, rotation, ground forces, sequencing on and on are great but without enough hand and arm strength you cannot transfer the forces into the ball. It’s the #1 limiting factor for speed in my opinion. The guys you listed are not big by any stretch of the imagination but I guarantee you they have incredible grip strength. Like effortlessly crush your hand in a handshake type strength.

Jamie and I are the only sub 200 pounders since 1990

[Valtiel]

2 hours ago, MonteScheinblum said:

Jamie and I are the only sub 200 pounders since 1990

Can that be retroactively revoked if someone is then *above* 200 for long enough?