Who Pushes Off With Their Trail Leg?

[hoselpalooza]

2 minutes ago, iacas said:

He's not pushing off here.

yes, he is. and later hashimoto explains his quick pressure shift forward as a result of the push off here.

Just now, saevel25 said:

Pushing off would indicate a spike. Since the pressure goes from 80 trail foot to immediately 80 forward foot, there is no spike, so no push off. 

you missed the spike which occurs half a frame earlier. it moves from 68 -> 80. 

3 minutes ago, saevel25 said:

2. The measured pressure under the trail foot does not spike. 

this is also incorrect. watch the video again. the pressure on the lead foot jumps from 20 -> 74.

[saevel25]

1 minute ago, hoselpalooza said:

this is also incorrect. watch the video again. the pressure on the lead foot jumps from 20 -> 74.

Sorry, that was a mistake, but also it was edited while you were posting. That is why your quote of mine does not match my post now. 

2 minutes ago, hoselpalooza said:

you missed the spike which occurs half a frame earlier. it moves from 68 -> 80. 

Still the backswing. You admit it in your post anyway that it goes to 80 at the top of the backswing. So, stop shifting stuff to make it look like you are making solid points. Be consistent. 

[hoselpalooza]

Just now, saevel25 said:

Still the backswing. You admit it in your post anyway that it goes to 80 at the top of the backswing. So, stop shifting stuff to make it look like you are making solid points. Be consistent.

after making bogus points easily refuted with data from the video you're still not making any sense. 

both of the pressure spikes which you said didn't exist are plain to see, which you admit, but you still refuse to believe those pressure spikes were caused by pushing off of the right foot. the data indicate this, the qualified professional performing the analysis indicates this, in another article kevin said he wants to feel this early in the downswing, and so on. 

are we having fun yet? /s

[Shindig]

36 minutes ago, hoselpalooza said:

in another article kevin said he wants to feel this early in the downswing, and so on. 

Lots of lessons are based around feeling something that isn't real in order to cause something real to happen.  

[boogielicious]

It’s is like debating with a flat-Earther.

[Piz]

This issue used to come up, on occasion, when I was coaching pitchers.  Some people say you have to push off, some say you stand tall and fall, and some don't give it a lot of thought.  The bottom line, for me, is this: if you are going to rotate your upper body you need a modicum of traction.  Imagine trying to throw a baseball, or swing a golf club, while standing on ice.  That is where I think the notion of pushing off comes from.  

Another way to look at it is to consider ambulatory activity.  (We don't use the W-word around pitchers)  We take smaller steps when traversing slippery surfaces lest our feet lose their purchase.  We keep the upper body quite still to minimize lateral stress on the lower body...specifically the feet.  

So...you can think of it either way: either you are going somewhere or staying put.  And in either case you need some traction to do so.

[Slim_Pivot]

1 hour ago, Piz said:

This issue used to come up, on occasion, when I was coaching pitchers.  Some people say you have to push off, some say you stand tall and fall, and some don't give it a lot of thought.  The bottom line, for me, is this: if you are going to rotate your upper body you need a modicum of traction.  Imagine trying to throw a baseball, or swing a golf club, while standing on ice.  That is where I think the notion of pushing off comes from.  

Another way to look at it is to consider ambulatory activity.  (We don't use the W-word around pitchers)  We take smaller steps when traversing slippery surfaces lest our feet lose their purchase.  We keep the upper body quite still to minimize lateral stress on the lower body...specifically the feet.  

So...you can think of it either way: either you are going somewhere or staying put.  And in either case you need some traction to do so.

Whats the "W-word"?  Wide? Wet? 

[iacas]

2 hours ago, Piz said:

The bottom line, for me, is this: if you are going to rotate your upper body you need a modicum of traction.  Imagine trying to throw a baseball, or swing a golf club, while standing on ice.

You may have missed the video @billchao made a few pages ago.

54 minutes ago, Slim_Pivot said:

Whats the "W-word"?  Wide? Wet? 

Walk.

---

I'm traveling all day, so if this debate heats up again, I'm here to throw a little water on it pre-emptively.

As briefly as I can, here's why we know that while it's possible to push off, high level players don't:

• Empirically, none of >100 Tour players seen on SwingCatalyst or other pressure plates are seen "pushing off."
• Biomechanically, it wouldn't make sense to push off. Ph.D. biomechanists can tell you this, and I've talked with several such people throughout my career. Among other things, it would tend to shift the moment to the trail side of the COM, which is anti-rotational (i.e. it would apply more clockwise force from the face-on view to the golfer).
• We've attached electrodes and thus studied what muscles activate during the golf swing, and the trail leg is seen doing very, very little in high-level players.

If someone did literally "push off" with their trail leg from the trail side to the lead side late in the backswing or early in the downswing, we would likely see something from the list below occurring:

• The trail knee extending. In most cases, it actually increases in flex early in the downswing. A flexing knee reduces pressure.
• The trail foot remaining flat. In most cases, the heel comes up and the foot banks inward, indicative of reducing pressure.
• An increase in the area and/or the magnitude on the pressure mat. Instead, we see the area shifting to a smaller area (the trail toe area) and/or the magnitude decreasing.
• Corresponding to the item just above, the actual amount of force (and the percentage, when viewed that way and if it's < 100%), would "spike" on the trail side. Instead, we see the number and percentage decreasing.
• We'd see the trail foot wanting to slide out backward, away from the target. Instead, we see the foot slipping out behind the player, perpendicular to the target line (because the hips are rotating counter to that direction). (As @billchao showed, your foot would be far, far less likely to slip out if you were actually using it to push off. Pushing off would increase the pressure and thus the friction. Feet slip out because they have less friction from decreased forces. On a mat, we'd measure shear forces away from the target line. Instead, we see them in the direction the foot actually slips - perpendicular to the target line.
• If you think the pushing is downward (since shear forces indicate it's not backward), we'd see elevation of the trail side. Instead, we see the trail side lowering the whole downswing.

How do players get their weight and pressure forward?

• There's a little bit of a fall. Because pressure increases on the trail side, it would seek a balance. The trail side is higher (that's why pressure has increased - you're moving the trail side upward, against gravity, and pushing against the ground to do so), so it "falls" left to try to balance out.
• Your core - and we know this from much of the above - "slides" your hips forward a little bit.
• Later in the downswing (often from ~ 5.5 to 7.2), the left knee extends FAST, which really spikes the pressure distribution left and aids in turning. The right leg is at this point "pulled along" and often extends by the right hip being pulled forward. Even at this point, it's not "pushing."

Nobody's debating these two things:

• It's possible to "push" with the trail leg. But no high-level player has been seen actually doing it.
• That some players feel that they're pushing with their trail leg. Feel ain't real.

Now, I may have missed some things, and I was as brief as I could be given that I have to pack up and get in the car for a long day for my daughter's tournament, but there you go. There's really only one person debating this stuff, and unlike @mvmac and myself, he's not spent thousands of hours studying this stuff. He's not talked with Ph.D biomechanists. He's not seen hundreds of pressure traces of high-level players. He thinks his "feel is real," and he's relying almost entirely on that to see things not as they are, but how he wants them to be.

[saevel25]

So I decided to take this seriously in that I tried to push off with my trail leg as something I should be working on. Meaning, I applied slow specific intent. 

I tried to feel what it felt like to push off towards the target. Then I tried to feel what it was like to push off closer to impact (hips open). Then I tried implementing a push off, and it didn’t go well. You can see that it’s not a movement that works well, at least for me. Pushing off the back foot leads to me being launched towards the target uncontrollably. What happens more often is the hip slides forward and the torso turn, and my back foot is dragged off the ground by rotation and left side extension. 

[Vinsk]

1 hour ago, saevel25 said:

So I decided to take this seriously in that I tried to push off with my trail leg as something I should be working on. Meaning, I applied slow specific intent. 

I tried to feel what it felt like to push off towards the target. Then I tried to feel what it was like to push off closer to impact (hips open). Then I tried implementing a push off, and it didn’t go well. You can see that it’s not a movement that works well, at least for me. Pushing off the back foot leads to me being launched towards the target uncontrollably. What happens more often is the hip slides forward and the torso turn, and my back foot is dragged off the ground by rotation and left side extension. 

@hoselpalooza doesn’t push off either. However, he’ll never just succumb to that so I’m leaving it at ‘ I believe that he believes he’s doing it.’ Until he puts up GRF plates on himself in a video and shows he’s reading it correctly ..I’m not convinced otherwise. 

[ncates00]

I think boditrack traces, swing catalyst data, and other metrics prove no good golfers push off their back foot.  The data shows pressure increasing in the front foot.  If the push off the back foot were true, we would most certainly see a pronounced increase in pressure in the trail foot through the downswing, but pros are getting to their left side  near 90% at impact.  Some will get a Z curve with driver where their trace will go forward but then "back up" to help with their hitting up with driver; some will even get a "ghost trace" where they're airborne.  If anything, those such players are pushing back off the ground from their front foot.  

[DrMJG]

I, also, thought you needed to push off of the trailing leg, as one might do in baseball.  But what resulted, in that form, was that everything else, from hip turn to club face through the swing was off.  The first aspect my coach changed was this; he made me focus on my left leg the moment the club moved towards the down swing.

It was difficult to change the concept and took a LOT of mirror work, checking the club hands and hips/legs at all the check points often discussed in these threads.

If I have any sort of feel, it is that when my weight transfers left thru the stages the swing, I feel nothing from the right leg, it becomes weightless. (To me, a "good feel" comes only when the mechanics are working; you become aware of only the good mechanics.)

Then I saw this and became aware of just how the trailing leg has minimal aspect in the swing.

 

Edited June 8, 2019 by DrMJG

[boogielicious]

18 hours ago, saevel25 said:

So I decided to take this seriously in that I tried to push off with my trail leg as something I should be working on. Meaning, I applied slow specific intent. 

I tried to feel what it felt like to push off towards the target. Then I tried to feel what it was like to push off closer to impact (hips open). Then I tried implementing a push off, and it didn’t go well. You can see that it’s not a movement that works well, at least for me. Pushing off the back foot leads to me being launched towards the target uncontrollably. What happens more often is the hip slides forward and the torso turn, and my back foot is dragged off the ground by rotation and left side extension. 

Thank goodness that is not your preshot routine. 😜

Here is a video from a few weeks back. I've been working on getting my weight more towards my right leg in set up with my instructor. It has more to do with my head position, but part of the feel I have is more weight on the right foot. 

But as you can see in the video, as soon as I begin the downswing, my right knee bends and right heel starts to lift. It can feel like I am pushing with the ball of my right foot, but I'm not. My body starts to rotate and the weight goes to the left side. What I am really feeling is my right foot starting to tilt on the ball of the foot. I tend to keep too much weight back on the right foot and am working to eliminate that with better hip and shoulder rotation. 

 

[hoselpalooza]

you guys are comically wrong about this. literally everyone pushes off to the right to some extent because of physics. some golfers just do so more than others. 

"With sufficient traction between the golfer's feet and the surface, the horizontal force allows the golfer to push in one direction to move in the opposite direction (for example pushing to the right to move the body mass to the left at the beginning of the downswing for a right-handed golfer)."
https://www.swingcatalyst.com/learning-center/articles/ground-reaction-force

dr. scott lynn, PhD and research director at swing catalyst discussing pushing off of the trail foot during a swing catalyst certification course:

some key points so you don't have to watch it all:

6:55
demonstrates pushing off of trail foot to shift COP/COM forward

8:24
demonstrates how kevin chappell pushes off with the trail foot at the top of the backswing to shift COP/COM forward

https://www.youtube.com/watch?v=PCvLsgVtfjM#t=6m55s

let's recap:

- numerous tour-level pros and instructors mention the trail leg push off, many likening it to throwing a baseball.
- sean foley, who uses swing catalyst and whose work with justin rose has been referenced by dr. lynn in certification courses, describes the push off as a "key source of power", and uses throwing a baseball as an analogy. https://www.youtube.com/watch?v=VWmUOyVa5hA
- every single baseball pitcher pushes off of the mound because of physics. if you missed the swing catalyst certification video explaining the physics behind this or if you still don't believe pitchers push off, just google it. there are numerous scientific studies which incorporate force plate data to describe the horizontal force pitchers use to achieve forward translation (or push off).
- and lastly, the research director for swing catalyst clearly demonstrates/explains how some elite golfers, kevin chappell in this case, push off of the ground with their trail foot toward the top of the backswing to move their COP/COM forward. and the swing catalyst website literally mentions how right-handed golfers push to the right to move the body mass to the left.

On 6/8/2019 at 3:01 AM, boogielicious said:

It’s is like debating with a flat-Earther.

@boogielicious, this is my favorite comment so far; i really appreciate your use of irony. because, you know, physics... ;) 

Edited June 9, 2019 by hoselpalooza
broken image link

[hoselpalooza]

On 6/8/2019 at 2:37 PM, ncates00 said:

I think boditrack traces, swing catalyst data, and other metrics prove no good golfers push off their back foot.  The data shows pressure increasing in the front foot.  If the push off the back foot were true, we would most certainly see a pronounced increase in pressure in the trail foot through the downswing, but pros are getting to their left side  near 90% at impact.  Some will get a Z curve with driver where their trace will go forward but then "back up" to help with their hitting up with driver; some will even get a "ghost trace" where they're airborne.  If anything, those such players are pushing back off the ground from their front foot.  

boditrak is one dimensional so it won't show forward translations (or push off). i just thought it was easy enough to see/extrapolate but apparently that's not the case for others.

you should review the swing catalyst information i shared above, including the clip from the swing catalyst certification seminar taught by the PhD director of research.  

On 6/7/2019 at 11:01 PM, Vinsk said:

On 6/7/2019 at 10:57 PM, hoselpalooza said:

it's possible to make a lateral shift toward the target by pushing off with the trail foot before completing the backswing. 

Of course it’s possible. But that’s not what’s happening. It’s also possible to shake your head violently during the backswing as well. 

i really should have phrased this differently. it's physically impossible to move the COP/COM toward the target without pushing off with the trail foot near the top of the backswing. it's just the extent to how much golfers push will vary depending on things like foot dominance, how they like to shift pressure, etc.

again, don't take my word for it. just look at the information i've already posted. 

On 6/8/2019 at 6:34 AM, Piz said:

This issue used to come up, on occasion, when I was coaching pitchers.  Some people say you have to push off, some say you stand tall and fall, and some don't give it a lot of thought.  The bottom line, for me, is this: if you are going to rotate your upper body you need a modicum of traction.  Imagine trying to throw a baseball, or swing a golf club, while standing on ice.  That is where I think the notion of pushing off comes from.  

Another way to look at it is to consider ambulatory activity.  (We don't use the W-word around pitchers)  We take smaller steps when traversing slippery surfaces lest our feet lose their purchase.  We keep the upper body quite still to minimize lateral stress on the lower body...specifically the feet.  

So...you can think of it either way: either you are going somewhere or staying put.  And in either case you need some traction to do so.

this is the closest somebody's come to acknowledging push off happens. thank you for braving the storm. 😂 

Edited June 9, 2019 by iacas
Removed moderation complaining.

[hoselpalooza]

@iacas, you might want to re-up on your swing catalyst certification.

source: https://carolinas.pga.com/wp-content/uploads/sites/3/2019/03/Dr.-Scott-Lynn-PhD-Swing-Catalyst.pdf

[saevel25]

28 minutes ago, hoselpalooza said:

(for example pushing to the right to move the body mass to the left at the beginning of the downswing for a right-handed golfer)."

The lateral shift in the golf swing is not a push off from the right foot. Especially in transition.

You have never addressed the fact that golfers gain flexion in their right knee in transition. This alone shows that they are not pushing off.

Ever use a dead lift machine at a gym? To move the weight you need to "Push" it with your leg. It's impossible to push it if you gain flexion in the leg.

Again, how is a golfer pushing off in transition when the leg is gaining flexion well into the downswing? 

34 minutes ago, hoselpalooza said:

demonstrates pushing off of trail foot to shift COP/COM forward

He did the same thing I did trying it out on the range, he pushed himself way off balance. Hence, golfers do not push off. They would lose balance. 

Andrew Rice describes the shift in pressure well. He doesn't once talk about pushing off. He talks about what the numbers actually show. 

1. Increase in pressure to the top of the backswing on the trail foot
2. Decrease in pressure to about 50/50 when the club is at A5 (parallel to ground in downswing) 
3. Majority of pressure under the lead foot at impact. 

You can see Stewart's pressure smoothly fluctuates with no pressure spikes you should see if he pushed off. 

 

46 minutes ago, hoselpalooza said:

numerous tour-level pros and instructors mention the trail leg push off, many likening it to throwing a baseball.

Already been addressed. Tour players are routinely wrong about what really happens. Slow Motion video has been a great boon to golf instruction since it has proven many swing feels as myths.  

47 minutes ago, hoselpalooza said:

sean foley, who uses swing catalyst and whose work with justin rose has been referenced by dr. lynn in certification courses, describes the push off as a "key source of power", and uses throwing a baseball as an analogy. https://www.youtube.com/watch?v=VWmUOyVa5hA

Sean Foley's comments really contradict themselves. 

1. He says people have a bad tendency to get their weight too far forward too soon. 
2. He claims people should focus on getting off their right side.... I believe these are the same thing.  

Also, his drill is not pushing off, it's rotating through as much as possible. Also, he doesn't even come close to performing what he says he is doing, pushing off. 

1. His right knee if flexed way late in the downswing. An indication that he is not pressing into the ground. As you need to extend the leg to push off. 

2.His right leg is still FLEXED!!! His left leg is fully extended. He is not pushing off at all with his right foot. He has pushed down hard with his left leg though. 

 

3. He finishes by continuing to turn as much as possible. This drill is more about not letting the body hang back due to lack of turn and weight shift than pushing off. 

 

 

[hoselpalooza]

1 minute ago, saevel25 said:

The lateral shift in the golf swing is not a push off from the right foot. Especially in transition.

You have never addressed the fact that golfers gain flexion in their right knee in transition. This alone shows that they are not pushing off.

Ever use a dead lift machine at a gym? To move the weight you need to "Push" it with your leg. It's impossible to push it if you gain flexion in the leg.

Again, how is a golfer pushing off in transition when the leg is gaining flexion well into the downswing? 

just so we're clear, you're saying that the PhD director of research at swing catalyst is wrong about this?

do you want me to toss out more data published by other PhD's which supports the fact that golfers, to some extent, push off of their right side?