Shoulder Plane vs Arm Plane

I've noticed, looking through different swings on YouTube, that a lot of the pros have their arms steeper than their shoulders at the top of the backswing (notably Rory, Tiger, Phil, and Spieth). I was just curious as to whether there was something about the steeper arms that is advantageous over having the arms more parallel or flatter than the shoulders (ala Matt Kuchar). Is it something that is beneficial, or is it just something that may be more common?

Are they just more flexible? It seems like it could give you more leverage if your shoulders are flexible enough?

Nicklaus was fairly upright with the arms too. May be somewhat harder to do well with longer clubs as a shorter player (unless you grip down) as there may be less room for a wide steep arc with the shoulders closer to the ground.

Advantage may be a bit more potential energy due to gravity from the higher hands position. Realizing that extra potential energy will still depend a lot on how you bring the club to the ball, though. Brandel Chamblee said that an upright swing is an advantage from the rough.

Kuchar's 'single plane' action is intended to be more consistent / mechanically simpler / less timing dependent with the arm swing more matched to the shoulder turn.

This is what I originally thought about, but the fact of the matter is that the extra potential energy from raising your hands about 6 inches is approximately 75 joules when you assume a club weight of 500 grams. This equates to .5 m/s (or 1.1 mph) of velocity in a straight up vertical drop of the club over someone else, assuming that they are 100% efficient in using that potential energy to gain extra clubhead speed. That doesn't seem like a significant enough reason to have most players on tour swinging in such a manner, just because I know that the reality is that working out and just refining your technique would have far greater impacts on clubhead speed as opposed to a change in the height of the hands. This is still all assuming that they are 100% efficient in using the potential energy to their advantage, which I suspect is not the case but cannot prove since I don't have a full understanding of the physics in a golf swing.

I also heard this, but this is another thing that prompted me to ask why the steeper arm angle is more popular. If the "single plane" is more consistent and less dependent upon timing, why wouldn't more players use it? Conversely, how would someone play just as consistent golf with the vertical plane unless they had significantly better timing? This is another question I have, but didn't ask in the original post just because it seemed a little bit off from my main question.

I know Rory and Rickie are only 5'9", and they both are the same with the shoulder more upright. It seems to span the height spectrum as a common occurrence, and the only person I could immediately see different was Matt Kuchar who's actually 6'4", which makes me wonder if longer clubs are a factor.

Sorry, I'm not picking on you or your post, I just noticed a lot of things in it that I had wondered previously.

As for unofficial counts (and I have a feeling this is an unscientific count) I found a website that actually had at least some numbers for players with varying shoulder and arm angles at the top of the backswing: http://www.aroundhawaii.com/lifestyle/health_and_fitness/2013-08-the-backswing-plane-survey-of-tour-professionals.html (As a sidenote, I would have just combine the last three categories to sort them as flatter/equal to shoulders and steeper than shoulders) The count they came up with was 15 players with an arm that was equal to or flatter than their shoulder plane (counting the old Rickie swing) and 165 that were above the shoulder.

It's obvious that that website is pushing for very steep arms at the top of the backswing, and the count is probably off at least some, I still find it somewhat interesting that there is such a large discrepancy between the different kinds of swing. I'm specifically hoping that Mvmac, Iacas, or someone else who definitively knows the answer could shed some light on this for me.

Yeah, I grant you it's minimal. It was a brainstorm thought. Still, the acceleration of gravity is constant and free. Also, isn't it additive to any acceleration the muscles create at each point in time in the downswing?

If not helpful for speed, perhaps it helps the arms automatically (gravity guided) track on a plane / path that is closer to the target line with less compensation / effort than a flatter plane?

As far as Kuchar, one plane is distinct from 'upright'. Yes, Kuchar's arms are aligned with his shoulders, but he is slightly more bent over (and so a bit more upright with his driver swing plane) at the waist than say Hogan was. But both their left arms roughly align with their shoulders at the top (single-plane as I understand it). Hogan was more two-plane in his 'Power Golf' swings (hands well above shoulders), though.

One thing for sure is that clubs are more upright in lie than they used to be and that (as well as offset) is intended to help amateur golfers draw the ball and get more distance. So that is probably closer to a functional justification for upright arms. May facilitate a steeper arc into the ball facilitating lower, drawing flight for penetration / distance.

Or it might be that upright facilitates a cut (Nicklaus) so that helped (or self-selected) those players who were more upright with their arms in their formative years to reduce the amount of draw more upright club lies produce and thereby got a tighter dispersion. When Bubba hit his big hook at Augusta he seemed to rehearse and use a flatter arc with his arms than the extremely steep L arm with his standard driver swing. Would be interesting to see results of the same survey for earlier eras and see if there was the same ratio of two-plane to one-plane swings?

Food for thought.

Just a quick comment here. It isn't directly additive once the arms begin to accelerate the club faster than gravity itself. At that point it just makes it so that it requires less force to accelerate the club further, but the main limiting factor usually isn't the force you can apply to the club but instead the distance that the club has to accelerate and the speed at which someone's body is physically capable of swinging the club.

I get you, but I wasn't thinking of the simple acceleration on the clubhead, but he impact on the hands delivered through the lever of the club. In other words, if there is a small amount of free acceleration on the arms / hands wouldn't that small amount multiply through the moment arm of the club as it releases through impact? A guy who models the golf swing wrote: "more hand speed...eventually translates into clubhead speed".

Don't many players use the 'free ride down' / 'gravity move' to help guide their 'drop into' the slot coming into delivery?

Or maybe the 2-plane bias on tour has something to do with " the benefit of a shorter moment arm for delivering shoulder torque to the hands"?

Your post seemed to be saying that the arm position is just the result of how they moved the club back. Do you see no significant pluses / minuses in '2-plane' vs. '1-plane'? If so, why do you think the distribution among pros is uneven (assuming the survey was fairly accurate)?

Funny, I was gonna ask about the pro's standing so close to the ball. Saw Stenson, when he was playing shortish irons, and thought to myself, dang he stands close to the ball, if I did that, it'd be a S%$#k for sure..

Are you sure you don't want to qualify that assertion? I think 8% is pretty significant.

There is no 8% gain.

http://www.tutelman.com/golf/swing/models2.php#lessons

It says gravity accounts for 8% of your swingspeed. That's gravity over the course of more than 6'. 2-3" won't make a difference.