Technical Details
- Variable Type: Discrete Metric
- Data Type: Float
- Units: × height (ratio to athlete height)
- Column Name:
contact_phase_wrist_height_per_ht - Measurement: Vertical height of the dominant-side wrist joint center above the ground at Apex, divided by athlete height
Description
Contact phase wrist height (normalized) expresses the wrist height at ball contact as a multiple of the athlete’s own height, rather than an absolute distance. Normalizing by height makes the metric comparable across athletes of different sizes. Values above 1.0 indicate contact is made above the athlete’s own standing height, typical of an overhand serve reaching upward. This is distinct from Contact Phase Wrist Height, which reports the same measurement as an absolute distance in meters.Use Cases
- Contact point consistency across athlete sizes
- Toss and strike height
- Comparison across players or trials