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# Lead Knee Angle at Ball Contact

> Amount of lead knee flexion at ball contact. This measures the knee angle of the front leg at the instant of impact.

## Technical Details

* **Variable Type:** Discrete Metric
* **Data Type:** Float
* **Units:** °
* **Column Name:** `lead_knee_angle_at_ball_contact`
* **Aggregation:** mean
* **Precision:** 0
* **Measurement:** Lead knee flexion angle
* **Timing:** At ball contact event
* **Typical Range:** 13 – 28 °
* **Optimal Direction:** Middle — moderate values are optimal

## Description

Lead knee angle at ball contact measures the amount of flexion in the lead knee at the moment of ball contact, indicating the front leg position and stability during impact.

## Normative Ranges

Percentile distributions by competition level from the 2026 Q1 dataset; the optimal range spans the 25th–75th percentiles.

| Population         | Optimal Range (25th–75th) | 10th | 25th | 50th | 75th | 90th |
| ------------------ | ------------------------- | :--: | :--: | :--: | :--: | :--: |
| Youth              | 22 – 34 °                 |  18  |  22  |  27  |  34  |  39  |
| High School        | 19 – 29 °                 |  15  |  19  |  24  |  29  |  32  |
| College            | 10 – 23 °                 |   7  |  10  |  16  |  23  |  32  |
| Professional       | 8 – 17 °                  |   6  |   8  |  11  |  17  |  21  |
| Broad (All Levels) | 13 – 28 °                 |   8  |  13  |  21  |  28  |  34  |

## Use Cases

* Front leg stability analysis
* Knee mechanics assessment
* Impact position evaluation
* Balance optimization