> ## 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.

# Repetition Time

> Time from seat off to sit for each sit-to-stand repetition, with its mean, variability, and change across the capture.

## Technical Details

* **Variable Type:** Discrete Metric
* **Data Type:** Float
* **Units:** seconds (s); percent (%) for CV and Change
* **Column Name:** `repetition_time`, `mean_repetition_time`, `repetition_time_cv`, `repetition_time_change`
* **Optimal Direction:** Lower is better
* **Measurement:** Time from [Seat Off](https://docs.uplift.ai/biomechanics/activities/stability/sit_to_stand/events/seat-off) to [Sit](https://docs.uplift.ai/biomechanics/activities/stability/sit_to_stand/events/sit) of the same repetition

## Variants

* **Repetition Time** (`repetition_time`) (per repetition): time from Seat Off to Sit.
* **Mean Repetition Time** (`mean_repetition_time`) (summary): average Repetition Time across all analyzed repetitions.
* **Repetition Time CV** (`repetition_time_cv`) (summary): coefficient of variation of Repetition Time, `100 × standard deviation / mean`. Requires at least two repetitions.
* **Repetition Time Change** (`repetition_time_change`) (summary): percent change from the first to the last repetition, `100 × (last − first) / first`. Positive values mean the last repetition was slower than the first. Requires at least two repetitions.

## Description

Repetition Time is the duration of one full sit-to-stand-to-sit cycle.
Time spent seated between repetitions is excluded, so a pause in the chair does not lengthen Repetition Time.
Mean Repetition Time summarizes overall speed, Repetition Time CV describes how consistent the pace was, and Repetition Time Change indicates whether the person slowed down over the capture.

Repetition Time includes all analyzed repetitions, including those flagged as [invalid](https://docs.uplift.ai/biomechanics/activities/stability/sit_to_stand/metrics/repetition-validity).

## Use Cases

* Overall sit-to-stand speed
* Pacing consistency across repetitions
* Fatigue or slowing over the test


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.