> ## 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.

# Fatigue Index

> A player's freshness at a point in the game.

> [!WARNING]
>
> The Game Data API is in preview. Endpoints, fields and limits may change before release, and it is not yet available to call.

## Technical Details

* **Variable Type:** Event
* **Event Type:** `fatigue_index`
* **Subtypes:** None
* **Layer:** `position` (player positions only)
* **Returned By:** [List Game Events](https://docs.uplift.ai/api-reference/game-data/events/list.md)
* **Filter:** `event_type=fatigue_index`

## Description

A player's freshness at a point in the game, from their recent and longer-term workload.

Every event has the same envelope fields, including time, frames, player, team, pitch coordinates, `phase`, `team_possession_id`, `player_possession_id` and `confidence`. See [List Game Events](https://docs.uplift.ai/api-reference/game-data/events/list.md). The fields below are specific to this type and are returned in `attributes`.

## Attributes

| Field | Units | Description |
| - | - | - |
| `time_s` | s | Time in the period the reading applies to. |
| `acute_freshness` | — | Freshness from recent efforts. |
| `chronic_freshness` | — | Freshness from longer-term load. |
| `band` | — | Freshness band, for example `amber`. |
| `recent_high_efforts` | count | High-intensity efforts in the recent window. |

## Example

Only the type-specific fields and a few envelope fields are shown.

```json theme={null}
{
  "event_type": "fatigue_index",
  "attributes": {
    "time_s": 2580,
    "acute_freshness": 64,
    "chronic_freshness": 82,
    "band": "amber",
    "recent_high_efforts": 6
  }
}
```

## Related

* [High-Speed Running](https://docs.uplift.ai/api-reference/game-data/event-catalogue/events/high-speed-running)
* [Get Physical Summary](https://docs.uplift.ai/api-reference/game-data/physical/get.md)


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