Hammer Curl
Thick arms need more than the biceps, and the hammer curl trains what standard curls miss. Holding the dumbbells with a neutral, palms-facing grip shifts the load toward the brachialis — the muscle underneath the biceps that pushes it up — and the brachioradialis along the top of the forearm. It also lets most lifters handle more weight than a supinated curl, which makes it a natural heavy companion to regular curls.
How to do the hammer curl, step by step
- Stand holding a dumbbell in each hand at your sides with palms facing your body, like holding hammers.
- Set your shoulders back, pin your elbows to your ribs, and brace lightly.
- Curl the dumbbells up while keeping the neutral grip the entire way — no rotation.
- Stop when the dumbbell approaches your front delt, with the elbow still at your side.
- Squeeze briefly at the top.
- Lower under control for two to three seconds to a fully straight arm, and repeat either alternating or both arms together.
Form cues that fix most reps
Imagine driving the thumb toward the shoulder to keep the path tight and the grip truly neutral.
You can go heavier here than on supinated curls — take advantage of it, but not at the cost of a still torso.
Curling across the body toward the opposite shoulder biases the brachialis even further if plain hammers get stale.
Common mistakes (and the fix)
Hammer Curl sets and reps
Match the rep range to your goal, not the other way around. These are the standard evidence-based ranges:
| Goal | Sets × Reps | Rest |
|---|---|---|
| Strength | 3–5 × 3–6 | 2–3 min |
| Muscle growth | 3–4 × 8–12 | 60–90 sec |
| Endurance | 2–3 × 15–20 | 30–60 sec |
How our free programs prescribe it
Upper B3 × 12–15PPL 6-day
Pull A3 × 12–15Powerbuilding 5-day
Pull · volume2 × 12–15Body-Part 5-day
Arms3 × 10–15
Hammer Curl FAQ
What muscles does the hammer curl work?
The brachialis and brachioradialis take the lead thanks to the neutral grip, with the biceps brachii still assisting. The brachialis sits beneath the biceps, so building it pushes the whole upper arm out and adds visible thickness near the elbow.
How many sets and reps should I do?
Three sets of 8–12 reps is the standard dose. Because the neutral grip is strong, hammer curls suit slightly heavier loading than supinated curls — many lifters pair 8–10 hard hammer reps with lighter, higher-rep standard curls in the same week.
Should I do hammer curls or regular curls?
Both, ideally. Regular curls bias the biceps brachii and its peak; hammer curls bias the brachialis and forearm, which build arm thickness. If you only have time for one in a given session, alternate them week to week rather than dropping one entirely.
More biceps exercises
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