> ## Documentation Index
> Fetch the complete documentation index at: https://docs.uplift.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Loading Phase Pelvis Tilt

> Maximum pelvis side-side tilt towards the rear during the loading phase of the serve.

<img src="https://mintcdn.com/upliftlabs/Ku7T6jLWrJyoK7uq/biomechanics/activities/tennis/images/pelvis-tilt.png?fit=max&auto=format&n=Ku7T6jLWrJyoK7uq&q=85&s=b52af12d33fe9c491559c5421e01e3e8" alt="Pelvis tilt during loading" width="500" height="500" data-path="biomechanics/activities/tennis/images/pelvis-tilt.png" />

## Technical Details

* **Variable Type:** Discrete Metric
* **Data Type:** Float
* **Units:** degrees (°)
* **Column Name:** `loading_phase_pelvis_tilt`
* **Measurement:** Maximum pelvis lateral (side-side) tilt towards the rear during the loading phase ([Ball Release](/biomechanics/activities/tennis/events/ball-release) to [Low Arm](/biomechanics/activities/tennis/events/low-arm))
  * Negative values indicate leaning to the dominant side
  * Positive values indicate leaning to the non-dominant side

## Description

Loading phase pelvis tilt is the maximum lateral tilt of the pelvis toward the rear during the loading phase. It reflects lower-body coiling and base position before the arm accelerates.

## Use Cases

* Lower-body coiling and loading
* Pelvis-trunk coordination
* Technique and consistency