> ## 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.

# Arm Slot Angle

> Abduction angle of the arm at ball release compared to vertical.

## Technical Details

* **Variable Type:** Discrete Metric
* **Data Type:** Float
* **Units:** °
* **Column Name:** `arm_slot_angle`
* **Aggregation:** mean
* **Precision:** 0
* **Measurement:** Abduction angle of arm (shoulder to wrist) at ball release
* **Reference:** Vertical (adducted) = 0°
* **Typical Range:** 39 – 63 °
* **Optimal Direction:** N/A — depends on pitching style

## Description

Arm slot angle measures the abduction angle of the arm (from shoulder to wrist) at ball release compared to vertical (adducted, 0°).

Sidearm and submarine throwers have larger arm slot angles than overhand throwers.
A perfectly side-arm release has an arm slot angle of 90°.

Uplift's arm slot categories broadly follow an article from Graeme Lehman: Do Different Arm Slots = Different Mechanics?
[https://treadathletics.com/arm-slot-differences/](https://treadathletics.com/arm-slot-differences/)

## 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              | 36 – 58 °                 |  23  |  36  |  50  |  58  |  70  |
| High School        | 41 – 60 °                 |  29  |  41  |  50  |  60  |  69  |
| College            | 41 – 71 °                 |  34  |  41  |  55  |  71  |  88  |
| Professional       | 38 – 61 °                 |  30  |  38  |  52  |  61  |  84  |
| Broad (All Levels) | 39 – 63 °                 |  29  |  39  |  51  |  63  |  75  |

## Use Cases

* Arm slot classification
* Release angle assessment
* Pitch consistency tracking