Balance
Balance in a swing context is the ability to maintain a stable base and controlled center of mass through the full motion — from setup through the end of the follow-through.
A swing that starts in balance can lose it at any point: excessive lateral sway moves the center of mass outside a stable position; falling back through impact is a common balance fault in golfers; lurching forward in a baseball stance is another. SwingVantage tracks center-of-mass displacement from pose estimation and flags significant deviations from the starting position. Balance faults are labeled as estimated because video-based center-of-mass computation is inherently approximate without force-plate data.
Example
A golfer's center of mass shifts 8 cm toward the trail foot at the top — within acceptable range — but drifts 12 cm trail-side at impact, a reverse-pivot balance fault.
Related terms
- Ground Reaction ForceGround Reaction Force (GRF) is the force the ground exerts back against an athlete's feet — the foundational energy input for the kinematic chain in every swing sport.
- Stability vs MobilityStability vs mobility is the biomechanical principle that joints alternate between roles — some must be stable anchors, others must be mobile movers — and faults often come from reversing these roles.
- Kinematic ChainThe kinematic chain is the sequence of body segments — from ground to tip — through which force and speed are transferred in a swing, with each segment's energy amplifying the next.
- Pose EstimationPose estimation is the computer-vision process that detects the positions of major body joints (keypoints) in each video frame, producing the skeleton that SwingVantage uses to measure angles and movement patterns.
Put this into your swing
SwingVantage can spot this in your own swing — free to start.