In 3D biomechanics, the "Kinematic Sequence" refers to the order in which energy is transferred through the body segments during the downswing. Every elite ball striker—regardless of how their swing looks on video—exhibits the exact same sequence.
The Sequence: 1-2-3-4
Energy must transfer from the ground up. If a segment fires out of order, or fails to decelerate properly, speed is lost and compensations must be made.
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1. Pelvis (Hips)
Initiates the downswing. Accelerates first, peaks in speed, then rapidly decelerates to transfer energy upward.
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2. Torso (Chest/Shoulders)
Fires next. It achieves a higher peak rotational velocity than the pelvis, then severely decelerates.
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3. Arms (Lead Arm)
Whips off the decelerating torso. Reaches peak speed just before impact, then brakes.
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4. Club
The final link. As the arms brake, the clubhead violently releases past the hands, achieving maximum velocity exactly at impact.
The Deceleration Principle
Speed is not created purely by acceleration; it is created by the sudden stopping of the preceding segment. Imagine cracking a whip: the handle must stop for the tip to snap.
Visualizing the Data
When looking at an AMM 3D graph (Advanced Motion Measurement), a proper sequence looks like a cascading waterfall of peaks, each higher and slightly later in time than the last.
| Segment | PGA Tour Avg Peak Velocity | Timing (Relative to Impact) |
|---|---|---|
| Pelvis | 450 - 550 deg/sec | Early Downswing |
| Torso | 700 - 850 deg/sec | Mid Downswing |
| Lead Arm | 1000 - 1200 deg/sec | Late Downswing |
| Club | 2000+ deg/sec (113+ mph) | Impact |