The Plumb Bob: How Pelvis Position at Setup Influences Ballstriking

At setup, golfers make decisions that influence how the club will travel through impact. Stance width, ball position, posture and body orientation all matter. One relationship we frequently evaluate in the TPI lab is what we call the plumb bob.

To identify a golfer’s plumb bob, find the midpoint between their feet, then compare it with the center of their pelvis. If an imaginary plumb bob were dropped from the pelvis, would it fall behind, directly over or ahead of the center of the stance?

That relationship gives us a useful reference for understanding how a golfer is organizing their mass at address. It can also provide insight into the expected location of the bottom of the swing arc.

There Is No Single Correct Position

The goal is not to place the pelvis in the same position for every shot. The appropriate relationship changes with the club and the type of contact the golfer is trying to create.

With the best drivers in the world, the plumb bob is typically behind the center of mass as the golfer generally wants the club traveling upward at impact. 

With an iron, the golfer needs the low point far enough forward to strike the ball before the ground. Accordingly, the pelvis will commonly be more forward relative to the stance than it is with a driver.

A wedge tends to push that pattern farther. For many wedge shots, the golfer is trying to produce a downward strike with a low point in front of the ball. Elite wedge players will often set the center of the pelvis farther forward relative to the center of the stance.

A Setup Pattern Can Help Explain a Performance Pattern

This comparison becomes especially useful when a player performs well with one part of the bag but struggles with another.

In the example shown in the video, the player described ball striking as a strength and wedge play as a weakness. Their 3D data offered a possible clue. The pelvis moved progressively forward from driver to iron, which matched the expected pattern, but moved back again with the wedge. Instead of establishing the most forward plumb-bob position with the shortest club, the player set up in a position more likely to move the bottom of the arc back.

That does not prove that one setup variable caused every poor wedge shot. It does, however, provide a logical place to investigate. Before rebuilding motion, it is worth asking whether the address position is helping the golfer create the contact required by the shot.  After all, adjusting set up is one of the least invasive changes an instructor can make to a swing. 

Don't Change Position at the Expense of Pelvic Side Bend

Moving the pelvis backward or forward is not always as simple as shifting weight or sliding the hips laterally. When golfers move the plumb bob back, they may also raise the trail hip and introduce excessive pelvic side bend. That is not the setup pattern we typically see in great drivers of the golf ball.

Ideally, the pelvis remains relatively level at address, sometimes with the lead hip slightly higher, while the center of the pelvis moves into the desired relationship with the stance. Some golfers may need to soften a knee to find that position without tilting the pelvis.

If the golfer cannot separate those two adjustments, the limitation may not be purely technical. Restrictions in the hips or spine can affect the golfer’s ability to shift the pelvis while maintaining an appropriate pelvic orientation. That is where the Body-Swing Connection matters: a setup change that looks simple may require a physical capability the golfer does not currently possess.

Plumb Bob is a Reference, Not a Rule

The plumb bob is one piece of the setup, not a prescription that should be applied in isolation. Ball position, stance width, trunk position, shot intent and the golfer’s physical capabilities all influence how the club reaches impact.

But as a comparison across clubs, it can be extremely useful. In a well-organized setup, the pelvis generally moves from a relatively rearward position with the driver toward a progressively more forward position with irons and wedges. That progression helps create the changing low-point and attack-angle demands through the bag.

Getting the setup right does not guarantee perfect contact, but it does give the golfer a better opportunity to produce it.

---

If you're a golfer interested in a physical assessment, you can connect with a TPI Certified expert via our Find an Expert page.