Pull-up muscles worked
Every role here is for this technique: overhand grip a little wider than the shoulders, from a dead hang to the chin over the bar.
What muscles does the pull-up work?
The prime movers of the pull-up are latissimus dorsi, brachialis and biceps brachii. They produce shoulder adduction and extension, and elbow flexion. Six synergists assist, among them brachioradialis, teres major, the sternal part of pectoralis major and the lower trapezius. Five stabilizers hold joints and segments still, among them the wrist and finger flexors, infraspinatus, and teres minor.
Joint actions and their prime movers
| Joint action | Prime movers |
|---|---|
| Shoulder adduction and extension | Latissimus dorsi |
| Elbow flexion | Brachialis and biceps brachii |
Every muscle by role
A prime mover produces the lift’s main joint action against the load; a synergist assists that action, or adds a secondary action the lift needs; a stabilizer contracts mostly isometrically to hold a joint or a segment still. A role describes what the muscle does in the technique above, not how hard it works or how much it grows.
Prime movers 3
| Muscle | What it does here |
|---|---|
| Latissimus dorsi | Pulling the upper arms down to the sides |
| Brachialis | Elbow flexion |
| Biceps brachii | Elbow flexion |
Synergists 6
| Muscle | What it does here |
|---|---|
| Brachioradialis | Elbow flexion with the forearm turned down |
| Teres major | Shoulder adduction and extension |
| Pectoralis major, sternal part | Pulling the upper arm down from overhead |
| Lower trapezius | Pulling the shoulder blades down More active in the pull-up than the chin-up (Youdas et al. 2010). |
| Rhomboids | Rotating the shoulder blades down and drawing them in |
| Posterior deltoid | Shoulder extension |
Stabilizers 5
| Muscle | What it does here |
|---|---|
| Wrist and finger flexors | Gripping the bar |
| Infraspinatus | Holding the head of the humerus in its socket |
| Teres minor | Holding the head of the humerus in its socket |
| Rectus abdominis | Keeping the body from swinging |
| External oblique | Keeping the body from swinging |
Lowering and lifting
| Phase | What the prime movers do |
|---|---|
| Lowering | Latissimus dorsi and the elbow flexors lengthen as the body drops |
| Pulling | They shorten to lift the body to the bar |
Where these prime movers also work
- Latissimus dorsi: prime mover in the bent-over barbell row, chin-up and lat pulldown; synergist in the parallel-bar dip.
- Brachialis: prime mover in the bent-over barbell row, chin-up, lat pulldown and barbell biceps curl.
- Biceps brachii: prime mover in the bent-over barbell row, chin-up, lat pulldown and barbell biceps curl.
Compared with the other vertical pull lifts
- Chin-up: the same prime movers, synergists and stabilizers. The lower trapezius here: more active in the pull-up than the chin-up (Youdas et al. 2010). Biceps brachii in the chin-up: more active in the chin-up than the pull-up (Youdas et al. 2010). The sternal part of pectoralis major in the chin-up: more active in the chin-up than the pull-up (Youdas et al. 2010).
- Lat pulldown: prime movers in both, latissimus dorsi, biceps brachii and brachialis; prime movers only in the lat pulldown, teres major.
Sources
- Youdas et al. (2010), J Strength Cond Res 24(12):3404
- NSCA, Essentials of Strength Training and Conditioning, 4th ed. (2016)
The cited studies that measured muscle activity used electromyography, and a larger signal need not mean more force or more growth (Vigotsky et al. (2018), Front Physiol 8:985). The roles draw on those studies for which muscles a lift involves and how two lifts differ, never to rank one muscle against another.
The values are facts and free to use; this page’s selection and presentation are © 2026 ScienceQuest.