What is the preacher hammer curl?
The preacher hammer curl is a dumbbell curl performed with a neutral, palms-facing grip while your upper arm rests on the angled pad of a preacher bench. The pad removes momentum and shoulder involvement, so every rep is pure elbow flexion. The neutral grip shifts the emphasis from the biceps toward the brachialis, the muscle underneath that pushes the biceps up, and the brachioradialis along the forearm. It suits anyone who swings their standing curls, and lifters chasing arm thickness rather than just a biceps peak.
How to do the preacher hammer curl
- 1
Set the seat height
Adjust the seat so your armpit sits snug over the top of the pad and your whole upper arm lies flat against it. If the pad hits mid-triceps, you are set too high.
- 2
Grip neutral, start long
Hold the dumbbell with your palm facing in, thumb up. Lower to a nearly straight arm, keeping a soft 5-10° bend at the bottom to protect the biceps tendon.
- 3
Curl without lifting the elbow
Drive the dumbbell up until your forearm is just past vertical. Your elbow and upper arm stay glued to the pad from the first centimetre to the last.
- 4
Lower on a 3 s count
The stretched bottom position is where the preacher earns its keep. Fight the dumbbell down for a full 3 s, re-tension at the bottom, then curl again.
Pro tip
The last 15° of extension is where elbows get cranky on a preacher bench. With heavy dumbbells, stop just short of a dead-straight arm and save the full stretch for your lighter sets.
Common mistakes
Hips lifting off the seat.
Rising up and leaning over the pad recruits your whole torso to heave the weight. If you need body English on a preacher bench, the dumbbell is too heavy.
Dive-bombing the stretch.
Dropping fast into full extension loads the biceps tendon at its most vulnerable length. Preacher curls have torn biceps that way: control every centimetre down.
Elbow floating off the pad.
Lifting the elbow at the top turns the curl into a weak front raise and gives the muscle a rest exactly when it should squeeze. Keep the arm welded to the pad.
Copying your standing curl weight.
The pad removes the cheat that inflates standing numbers. Expect to use noticeably less weight here, and treat that as the exercise working, not you getting weaker.
Variations and progressions
Easier
Machine preacher curl
The pin-loaded version guides the path and lets you adjust the load in small steps, ideal for learning strict elbow flexion.
Harder
Paused preacher hammer curl
Add a 2 s pause near full extension and a 4 s lowering phase. The bottom position becomes brutal, and so does the growth stimulus.
No preacher bench?
Incline dumbbell hammer curl
Lie back on a 45-60° bench and let your arms hang: gravity fixes the upper arm behind your torso and loads the same deep stretch, no pad required.
How to program it
Three protocols by goal. Pick one per cycle and aim for progression on load or distance.
| Goal | Sets × distance | Load | Rest |
|---|---|---|---|
| Hypertrophy | 3 × 8-12 per arm | RPE 8 | 90 s |
| Eccentric focus | 3 × 6-8, 4 s lowering | Moderate | 2 min |
| Finisher pump | 2 × 15-20 | Light | 45-60 s |
Preacher Hammer Curl FAQ
Hammer grip or supinated grip on the preacher: which builds bigger arms?
Run both across the week, they do different jobs. The supinated preacher curl biases the biceps itself, especially the peak. The hammer version hits the brachialis and brachioradialis harder, which adds width to the upper arm and size to the forearm. If your arms look thin from the side despite decent biceps, the hammer grip is the one you have been skipping.
One arm at a time or both together?
One arm at a time is worth the extra minutes. You can centre your body behind the working arm, watch the elbow stay down, and give full attention to the 3 s lowering phase. Alternating also reveals strength gaps between sides that two dumbbells moving together will happily hide. Save the two-arm version for time-crunched sessions.
Why do my elbows ache after preacher curls?
Usually a dose problem: heavy loads taken fast into full extension, several times a week. Fix it by stopping 10-15° short of straight on heavy sets, slowing the eccentric, and checking the seat height, because a pad that is too high cranks the shoulder and elbow into a poor line. If a sharp pain shows up at a specific spot, drop the exercise for two weeks rather than pushing through.
