> ## 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.

# Landing

> The instant of ground contact after the jump.

## Technical Details

* **Variable Type:** Event
* **Data Type:** Integer
* **Units:** Frame number
* **Column Name:** `jump_landing_frame`
* **Required for QA:** True
* **Measurement:** First frame of ground contact after flight

## Description

Landing marks the instant when the athlete makes contact with the ground after the flight phase. This event defines the start of the landing phase and is used for landing mechanics and stiffness metrics.

## Use Cases

* Landing phase start
* Flight time (takeoff to landing)
* Knee valgus at landing
* Joint angles at landing