GEARS Pro Data: Axis Tilt vs. Pelvis Sway (Shift)

[iacas]

I have 61 swings (29 drivers, 32 irons (two of which are wedges) with full club and body data of men and women Tour players (or former Tour players) in my GEARS system. I've put them all in a spreadsheet and with that, I can plot a number of things against each other. I'm open to soliciting and creating charts that show you any of the data.

In each of these topics, I'll present the data in a chart of some kind and share the data in the quartiles (min, 25th, average, 75th, max) as well as the standard deviation.

Here's one such chart showing the pelvis sway and virtual spine tilt at impact for drivers and irons:

The plot above shows the pelvis sway 1️⃣ for each player (for each club) against the axis tilt (virtual spine tilt) 2️⃣ for each player. Irons are in purple, drivers in blue.

1️⃣ Pelvis Sway is measured from a starting point of 0.0" at address to the amount the center of the pelvis has moved toward the target (positive numbers) or away from the target (negative) at A7 (impact).
2️⃣ Virtual Spine Tilt is measured as the angle (vertical is 90°) from face-on from the center of the pelvis to the center of the shoulders. Less than 90° would show a player leaning his upper body toward the target, greater than 90° shows the player leaning away from the target. Lefties are normalized to match righties.

The charts below show the independent min, max, quartiles, etc. In other words, the low axis tilt of 94.5° may not (and is not) the low pelvis sway (1.6") player.

Irons	Axis Tilt	Pelvis Sway
Low	94.5°	1.6"
25th Percentile	101.2°	3.2"
Average	103.9°	4.7"
75th Percentile	106.5°	5.5"
High	113.4°	9.0"
Range	18.9°	7.4"
Std. Deviation	4.42°	1.72"

and

Drivers	Axis Tilt	Pelvis Sway
Low	101.4°	-0.5"
25th Percentile	104.0°	2.4"
Average	108.0°	3.5"
75th Percentile	111.1°	4.1"
High	118.4°	10.8"
Range	17.0°	11.3"
Std. Deviation	4.73°	2.03"

If you'd like to request some processed GEARS data, please send me a DM.

[Phil McGleno]

Surprised at the lack of comments here.

It does not surprise me that-

• more axis tilt from more pelvis sway generally
• more axis tilt with driver
• less pelvis tilt with driver

You see less upper body sway with the driver to get the axis tilting that much more I imagine-How much? Do you have the sway numbers for the upper body?

[iacas]

1 hour ago, Phil McGleno said:

Do you have the sway numbers for the upper body?

Yes.

Rib Sway A7	Drivers	Irons
Low	-2.6"	-0.1"
25th Percentile	-0.9"	1.5"
Average	0.4"	2.3"
75th Percentile	0.9"	3.1"
High	6.5"	5.7"
Range	9.1"	5.8"
Std. Deviation	1.68"	1.39"

 

[Ty_Webb]

Hi Erik,

Do you have the tilt and sway numbers at other points in the swing? I think it would be interesting to see the numbers at address (for tilt only obviously), half way back, top of backswing, half way down and impact. Not sure if there is an easy way to plot them all on one chart. 

[iacas]

1 hour ago, Ty_Webb said:

Hi Erik,

Do you have the tilt and sway numbers at other points in the swing? I think it would be interesting to see the numbers at address (for tilt only obviously), half way back, top of backswing, half way down and impact. Not sure if there is an easy way to plot them all on one chart. 

Yes. I have them at every point in the swing.

I could choose maybe eight of each swing (driver/iron) and plot them in a line graph so maybe I’ll do that. Send me a message if you didn’t already.

[GolfLug]

Just musing here as to what the takeaway would be - driver has more tilt and less sway compared to irons because of more of a sweep motion compared to irons which is a more of a 'forward swaying drive down' motion at impact?

Curious as to what would these number look like for a typical 40-something mid-capper. Few random case studies would be awesome if readily available. 

[iacas]

29 minutes ago, GolfLug said:

Just musing here as to what the takeaway would be - driver has more tilt and less sway compared to irons because of more of a sweep motion compared to irons which is a more of a 'forward swaying drive down' motion at impact?

Basically. 🙂 And as I said, it also shows you the ranges, and averages… etc. too. So you could see where you "fit" into that spectrum.