Kwon

In that video, Kwon compares two elite pro golfers - player 1 who is using a vertical-centralised (or small degree of leftwards-centralised) upper torso loading pattern during his backswing action and player 2 who is using a rightwards-centralised upper torso loading pattern during his backswing action.

Kwon claims that player 1 is going to produce a better pelvic/torso rotation during the downswing. He gives two reasons for his "opinion". He claims that player 1 is getting his body's COM shifted to the right more between P1 and P4 (compared to player 2 who shifts his pelvis targetwards in his later backswing). Secondly, Kwon claims that player 1 can generate a greater moment (torque), which is required to rotate the pelvis/upper torso counterclockwise in his early downswing, because he has a larger moment arm operating between P4 => P5 - even if he does not necessarily generate a larger magnitude of vertical GRF.

I don't disgaree with Kwon's theoretical reasoning, which is based on his theoretical methodology of describing the effect of vertical GRF's that he believes are causally responsible for rotating the pelvis/upper torso counterclockwise during the early downswing. However, I believe that his "theoretical model" does not correlate with the "real life" reality of many pro golfers' driver golf swing actions.

First of all, his theoretical model produces a moment (torque) that operates in the frontal plane. However, the pelvis and upper torso rotate in a much more horizontal plane in the early-mid downswing and they do not really rotate in the "up-and-down" manner demonstrated by Kwon. Secondly, Kwon totally ignores the contribution of pelvic girdle muscles (trail sided lateral pelvic rotator muscles) in causing a counterclockwise pelvic rotation between P4 => P5.

Consider some examples of pro golfers who use a rightwards-centralised upper torso loading pattern, and who are capable of generating very high clubhead speeds at impact in their driver swings.

First example - Tim Burke (2015 world long-drive champion).

Here is a second example of a long-drive champion - Jamie Sadlowski - who uses a rightwards-centralised upper torso loading pattern.

Image 1 is at address. Note that JS has his spine tilted to the right at address and that his head is vertically over a point on the ground that is just inside his right foot.

Image 2 is at P4. Note that he uses a rightwards-centralised upper torso loading pattern and he makes no attempt to pull his spine targetwards in a reverse-pivoting fashion between P1 => P4 (as recommended by Kwon) and that his head has not moved targetwards during his P1 => P4 time period.

Third example - featuring Jack Nicklaus.

Image 1 is at P3 and image 3 is at P4.

Note how JN pushes his pelvis targetwards during his clockwise pelvic rotation that happens between P1 => P4, and note that he has a rightwards-centralised upper torso loading position at P4.

Fourth example - featuring Milo Lines.

Image 1 is at address. Note that Milo Lines has a small degree of rightwards spinal tilt at address, and that his head is behind the center of his stance.

Image 2 is at P4. Note that he has a rightwards-centralised upper torso loading pattern (green line is parallel to his spine). I have drawn a red line vertically downwards from the center of his head and it is still positioned behind the center of his stance. Note that he is not reverse-pivoting and pulling his spine to a more vertical orientation (as recommended by Kwon).

Note how efficiently he rotates his pelvis between P4 (image 2) and P5.5 (image 3). Note that his pelvis is mainly rotating horizontally, and there is no up-and-down motion in the frontal plane axis.

Here are comparison images of Milo Lines and Jamie Sadlowski at P5.5.

Note that they both have a similarly efficient counterclockwise pelvic rotation happening in a relatively horizontal plane between P4 => P5.5, even though they both started from a rightwards-centralised upper torso loading position at P4.

In my previous post I contested Kwon's opinion that a pro golfer should have a centered (either vertical-centralised or left-centralised) upper torso loading pattern by P4. I demonstrated that many pro golfers, who are long drivers of the golf ball, have a rightwards-centralised upper torso loading pattern at P4.

I also disagree with Kwon's "shurn motion" teaching principle where he wants a golfer to first shift the pelvis in a re-centering motion between P3.8 => P4.5+ while increasingly pressure-loading the lead foot, and where he then wants the golfer to secondly use the pressure-loading of the lead foot to induce a pelvic rotation. I have argued that many pro golfers are rotating their pelvis counterclockwise from the very start of the downswing and that they are shifting their pelvis targetwards at the same time, with the degree of pelvis shift depending on the pelvic loading pattern at P4 (being greater for a golfer who has a rightwards pelvic loading pattern like Mickey Wright, being less for a golfer who has a centralised pelvic loading pattern like Jamie Sadlowski and being the least amount if the golfer has a leftwards pelvic loading pattern like Jack Nicklaus).

I thought that it would be instructive to analyse Milo Lines' driver swing in terms of the vertical/horizontal GRFs being generated and I contacted Milo to ask if he had been measured with a Swing Catalyst system. Milo sent me his Swing Catalyst tracing video, which lasts 22 seconds. Milo was measured by Scott Lynn as part of their Driving Force video project - see www.bebettergolf.net/drivingforce.html. You can purchase that Driving Force video for $30. Note that there is teaser video at the bottom of that webpage that lasts 11 minutes. I have not purchased the full video so I do not know what opinions were expressed by Scott Lynn in the full video.

What I am going to do in this post is provide my personal interpretation of Milo's Swing Catalyst measurements of his driver swing, and I am also going to make some golf instructional points that reflect my personal (subjective) opinion.

Milo starts at address with his pelvis centered and with his COP measurements distributed equally (50%) under each foot. Milo has a triggering motion where he momentarily increases the COP measurement under his lead foot to 95% of the total measurement, and that presumably allows him to push off the lead foot to initiate his backswing action.

Here is Milo at his P2.5 position.

This is the time point when the COP measurement under his trail foot reaches its maximum value (=69% of his total COP value as shown in the upper right corner of the image).

Here is a capture image of Milo at ~P3.8 (just before he starts to rotate his pelvis counterclockwise).

Note that he has 66% of his COP measurement under his trail foot. The tour average at P4 is 80%, but there is a large variance - JB Holmes has 100% at P4 while S&T golfers have only 50-60% at P4.

Note that Milo uses a rightwards-centralised upper torso loading pattern during his backswing action, but he uses a centralised pelvic loading pattern where his pelvis does not shift away from the target (as seen in Mickey Wright's and Gary Woodland's driver golf swing action). Therefore, it is understandable that that he does not have >80% of his pressure-loading COP measurement under his trail foot at ~P4 if his pelvis is still relatively centered between his feet at ~P4.

Here is a capture image of Milo at P4.5.

This is the end of the hip-squaring phase where Milo manifests the "Sam Snead sit-down squat look". Note that he still has 52% of his overall COP measurement under his trail foot. That means that he could perform a very efficient hip-squaring counterclockwise pelvic rotary motion between P3.8 => P4.5 without any marked degree of pressure-loading of the lead foot as recommended by Kwon and Sasho MacKenzie. I strongly suspect that Milo is using the active muscular contraction of his trail-sided lateral pelvic rotator muscles to induce his pelvis to rotate counterclockwise away from his "stabilised" trail leg/foot.

Look at the magenta colored graph. That graph measures the amount of horizontal side-force in a targetwards direction that is being exerted by the trail foot. I have drawn a red circular marker to show that Milo reaches his peak horizontal force at P4.5 (see the vertical line capped by a small transparent circle in the magenta colored graph). The black zone represents the pro tour average. Note that Milo's peak horizontal force just reaches the lower edge of the pro tour zone. It is understandable why Milo does not need to produce a large amount of horizontal force under his trail foot in his early downswing - because his pelvis is already centered at P4 and he does not have to re-center his pelvis by performing a large amount of pelvic shift motion during his hip-squaring phase that ends at P4.5. That fact also shows that Kwon's generic golf instructional philosophy of shifting the pelvis before rotating the pelvis does not necessarily make sense. Milo has already rotated his pelvis counterclockwise to square by P4.5 with no preliminary pelvic shift motion.

Look at the yellow colored graph. That graph measures the amount of horizontal GRF-generated torque being generated under the two feet to produce what Kwon calls the pivoting torque - as seen in this capture image at perfectgolfswingreview.net/KwonTorque3Two.jpg . I have drawn a blue circular marker to show that Milo has only generated a small amount of horizontal GRF torque by P4.5 (see vertical line capped by a small transparent circle). That means that Milo's very efficient hip-squaring pelvic rotary motion is happening between P3.8 => P4.5 without a major contribution from a pivoting torque. I think that it is only possible because Milo is primarily using the active muscular contraction of his trail-sided lateral pelvic rotator muscles to square his pelvis and he is not dependent on using his horizontal GRF pivoting torque forces (where the lead foot pushes away from the ball-target line while the trail foot pushes towards the ball-target line).

The cyan-colored graph is the vertical GRF graph produced by the lead foot. Note that Milo is not yet producing any measurable amount of vertical GRF torque at this point of his downswing, and that he efficiently squared his pelvis by P4.5 without even needing to pressure-load his lead foot in the manner recommended by Kwon and Sasho MacKnezie.

Here is Milo at his P5.5 position.

I have drawn a red circular marker over his yellow graph to show that Milo is reaching his peak horizontal GRF torque value at P5.5 and that the amount of pivoting torque being generated is very large (at the top level of the black pro tour zone). In other words, I think that Milo starts his pelvis rotation in his early downswing by using his trail-sided lateral pelvic rotator pelvic girdle muscles, but then continues to actively rotate his pelvis between P4.5 => P5.5 by primarily using a horizontal GRF-generated pivoting torque.

I have drawn a blue circular marker over his cyan-colored vertical GRF graph to show that Milo is producing a significant amount of vertical GRF under his lead foot by P5.5 (that has reached ~60% of his peak value). That significant amount of vertical GRF under his lead foot is needed to brace his lead leg/foot and prevent any pelvic swaying motion while he is actively generating a huge amount of horizontal GRF torque to continue his counterclockwise pelvic rotation - note how i) his lead knee remains bent, how ii) the outer border of his lead pelvis remains well inside his lead foot, and how his pelvis opens up more. I disagree with Kwon's opinion that the lead leg must straighten under the influence of a large amount of vertical-GRF being generated under the lead foot in order to induce a counterclockwise pelvic rotation - and I think that the main function of generating a finite amount of vertical GRF under the lead foot is primarily to brace the lead leg/foot while the pelvis is being rotated counterclockwise by the horizontal GRF pivoting torque.

Here is a capture image of Milo at impact.

Note that Milo has 83% of his overall COP measurement under his lead foot at impact - and that classifies Milo as being a front-foot pattern golfer (and not a reverse foot pattern golfer).

Note that his vertical GRF under his lead foot reaches its peak value at impact. Note that his horizontal GRF torque value is still very large (and well within the black zone), and I believe that it is allowing Milo to continue to rotate his pelvis to a very open alignment position by impact (and through impact).

Note that although Milo generates a very large vertical GRF under his lead foot in his later downswing, that he does not overly straighten his lead leg by impact (as seen in Tiger Woods driver swing and the driver swings of pro golfers who are "jumpers" like Justin Thomas, Justin James and many S&T golfers).

I personally think that Milo has a superb pelvic motional pattern during the downswing of his driver swing action, and I believe that he is using a non-Kwon pelvic motional pattern that much better fits the pelvic motional pattern that I personally recommend when it comes to describing/elucidating the underlying biomechanics/mechanics.

Jeffrey Mann.

https://newtongolfinstitute.proboards.com/thread/931/kwons-opinion-best-rotate-pelvis