Alternate Hammer Curl
The alternate hammer curl has you standing with a dumbbell in each hand, palms facing each other, curling one arm at a time as if hammering a nail straight up. It trains the biceps along with the brachialis and forearms, and the neutral, thumbs-up grip changes the emphasis slightly compared to a standard curl, giving your forearms more of the workload.
Why it works
Rotating your palms to face up during a standard curl brings the biceps fully into play, but keeping your palms facing each other throughout the hammer curl shifts some of that work onto the brachialis, a muscle underneath the biceps, and onto your forearms, which have to grip the neutral position the entire rep. Alternating arms rather than curling both together also lets you focus your attention fully on one side at a time, which tends to produce cleaner form and a stronger mind-muscle connection than curling two dumbbells at once.
Set up
- Stand tall holding a dumbbell in each hand, palms facing your body.
- Let your arms hang straight down at your sides, elbows close to your ribs.
- Keep your knees soft and your core lightly braced before the first rep.
How to do it
- Curl one dumbbell up toward your shoulder, keeping your palm facing inward the entire time.
- Keep your elbow pinned close to your side, not drifting forward or out.
- Squeeze at the top of the curl before lowering.
- Lower that arm with control as you begin curling the other side.
- Alternate arms in a steady rhythm, never resting one arm fully before continuing.
- Keep your torso still throughout, resisting any urge to swing for momentum.
Form cues
- Palms face each other the whole rep.
- Elbow pinned to your side.
- No body swing, no momentum.
- Squeeze at the top before lowering.
Breathing: Exhale as you curl the dumbbell up, inhale as you lower it back down.
Common mistakes
Swinging the torso or hips to help lift the weight.
Fix: Choose a lighter dumbbell and keep your core braced; if you need to swing, the weight is currently too heavy for strict form.
Letting the elbow drift forward away from the body during the curl.
Fix: Keep your elbow pinned close to your ribs for the entire rep; a drifting elbow reduces the demand on the target muscles.
Rushing the lowering phase instead of controlling it.
Fix: Slow the descent down; the lowering half of the curl builds as much strength as the lifting half.
Letting the wrist bend instead of staying neutral throughout.
Fix: Keep your wrist straight and firm, in line with your forearm, for the entire movement.
How to program it
- Start with 3 sets of 10 to 12 reps per arm, two or three days a week.
- It pairs naturally with a triceps exercise in the same session to balance the front and back of the upper arm.
- Progress by increasing the weight in small increments once 3 sets of 12 feel controlled on both arms.
- Works well toward the end of an upper-body session, since it's a smaller, more isolated movement than a compound lift.
Safety notes
- Choose a weight you can control through the full range without swinging; strict form matters more than heavy load here.
- Keep the wrist neutral throughout; a bent wrist under load can create unnecessary strain.
Exercise profile
- Force
- Pull
- Mechanics
- Isolation
- Category
- Strength
Frequently asked questions
What's the difference between a hammer curl and a regular curl?
A regular curl rotates your palms to face up, emphasizing the biceps directly. The hammer curl keeps your palms facing each other the whole time, shifting more work onto the brachialis and forearms while still training the biceps.
Should I alternate arms or curl both dumbbells together?
Alternating lets you focus fully on one arm at a time, which often produces stricter form and a stronger connection to the working muscle. Curling both together is faster and can feel more efficient. Either approach works; alternating is simply the more deliberate option.
How many hammer curls should I do?
Ten to twelve reps per arm, for 3 sets, is a solid starting point. Focus on strict form and a controlled lowering phase rather than chasing a high rep count.
Do hammer curls work the forearms?
Yes, more directly than a standard curl. The neutral grip requires your forearms to stabilize throughout the movement, which is part of why hammer curls are commonly included for forearm and grip development.