Sled Pull · Shoulder Roll (Hand-Over-Hand)

Why this matters

Hand-over-hand pulls one arm at a time, so every stroke tries to rotate the trunk toward the pulling side. The core's job is to resist that rotation — anti-rotation strength keeping the shoulders level while the arms alternate. When the core can't hold it, the pulling shoulder dips and the trunk rolls. That roll is wasted motion: energy goes into oscillating the spine instead of into the sled, and the lumbar takes an unnecessary rotational load every stroke.

Because the fault is rotational, it only shows from the front — a lateral clip can't see it.

What good looks like

From the front, the line across the shoulders stays close to horizontal even at the peak of each arm pull. The trunk faces the sled and stays there; the arms do the reeling while the core keeps the shoulders quiet.

Reading the result

• Stable (<15°): core anti-rotation is doing its job — energy goes to the sled, not the spine.
• Rolling (15°–30°): some rotational leak under heavier pulls; modest power loss and lumbar oscillation. Train Pallof presses and anti-rotation carries.
• Very rolling (>30°): significant rotation — the trunk is twisting with each pull instead of anchoring against it.

Coaching cues

• "Square shoulders to the sled" — the direct target.
• "Brace the core, let the arms work" — puts the anti-rotation job where it belongs.

How to mark

1. Use a frontal-view clip (athlete facing the camera) — a lateral clip won't show the dip.
2. Points: one acromion → the other acromion (the angle is direction-invariant).
3. Capture the peak of an arm pull, when the pulling side drops.
4. The tool reports the shoulder line's angle from horizontal.

Common mistakes: using a lateral-view clip (won't show the dip — the clip must be tagged Anterior/Posterior); drawing between collarbone points instead of acromions.

Related measurements

• Knee Anchor (Hand-Over-Hand) — the planted base that gives the core something to brace against.
• Elbow Flexion at Peak Pull (Hand-Over-Hand) — the arm draw that provokes the rotation.