# Single-Arm Overhead Dumbbell Extension: how to do it

- Main muscles: triceps
- Equipment: dumbbell
- Level: beginner
- 3D demo (side view): https://media.trainaq.com/exercises/single_arm_overhead_dumbbell_extension/45cca6da2e/side-m-720.mp4

## Steps

1. Stand tall and press one dumbbell straight overhead, upper arm by your ear.
2. Brace your abs and keep your ribs down.
3. Bend your elbow to lower the dumbbell behind your head.
4. Straighten your arm to return, keeping your upper arm still.

## Cues

- Elbow points forward, not out
- Upper arm stays by your ear
- Ribs down, no lean back

## Common mistakes

- Elbow flaring out; keep it close to your head.
- Arching your back; brace your abs and squeeze your glutes.
- Upper arm dropping forward; keep it vertical throughout.

## Starting position

Standing, feet hip-width apart (a short split stance is also fine), knees soft (about 175°), glutes and abs braced, ribs down, natural low-back curve, head neutral and in line with the spine. One dumbbell in the right hand (mirror for left), closed grip round the handle, palm facing forward and slightly in, wrist straight. The free hand rests on the hip.

## The movement

Only the elbow moves. The dumbbell travels in an arc behind the head and back up the same arc. The upper arm stays vertical and still; the shoulder does not shrug or press. Torso, hips and legs stay still: no backward lean, no rib flare.

## End position

(turnaround point): elbow bent so the dumbbell sits behind the head at about neck to upper-ear level, just clear of the head. Elbow flexion about 120° (accept 90–140°). Upper arm still vertical by the ear, or drawn back slightly by the weight (up to 10°); elbow still pointing up and forward, close to the head, not flared out.

## Tempo

Lower 2 s, pause 0.3 s, extend 1.2 s, hold 0.3 s.

## Form in numbers

| Measure | Target | Good range | Sources |
| --- | --- | --- | --- |
| Stance width | hip width | hip to shoulder width |  |
| Upper arm from vertical | 0° | 0–10° back |  |
| Elbow at top | 175° | 170–180° (no snap) |  |
| Elbow flexion at bottom | 120° | 90–140° |  |
| Elbow lateral flare | 0° | 0–15° |  |
| Dumbbell at bottom | behind head, neck to ear level | 2–5 cm clear of the head |  |
| Low-back arch added at bottom | 0° | 0–5° |  |

## Sources

1. [[ExRx.net: Dumbbell One Arm Triceps Extension (Internet Archive copy, 2022)](](https://web.archive.org/web/20221005123151/https://exrx.net/WeightExercises/Triceps/DBOneArmTriExt)
2. [[ACE: Triceps Extension (dumbbell, overhead)](](https://www.acefitness.org/resources/everyone/exercise-library/74/triceps-extension/)

Source: https://trainaq.com/exercises/single-arm-overhead-dumbbell-extension