Smart Workout Diary

Dumbbell Alternating Preacher Curl Hammer

The dumbbell alternating hammer preacher curl is an isolation exercise performed one arm at a time with the upper arm supported on a preacher bench and a neutral grip. It primarily trains the biceps and brachialis, while the forearms assist with gripping and elbow flexion. It supports arm strength and muscle development while limiting body swing.

Demonstration

Dumbbell Alternating Preacher Curl Hammer — demonstration 1
Dumbbell Alternating Preacher Curl Hammer — demonstration 2

Instructions

  1. Set the bench: Adjust the preacher pad so your armpits sit close to its top edge and your upper arms can rest firmly against it.
  2. Take position: Sit tall with a dumbbell in each hand. Place both upper arms on the pad and use a neutral grip, with palms facing each other.
  3. Start controlled: Let one arm extend toward the bottom without forcefully locking the elbow; keep the opposite arm still.
  4. Curl one arm: Exhale and bend the working elbow to raise the dumbbell toward the shoulder while keeping the upper arm pressed into the pad and the wrist neutral.
  5. Lower and alternate: Inhale as you lower the dumbbell slowly to the starting position, then perform the same repetition with the other arm. Keep your torso still throughout.
Muscle Group
Biceps
Other Muscle Groups
Brachioradialis
Type
Strength
Mechanics
Isolation
Equipment
Dumbbell, Bench
Difficulty
Beginner

Technique tips

  1. Use a manageable load: Choose dumbbells that allow a slow lowering phase without lifting the upper arm off the pad.
  2. Keep the wrist neutral: Do not bend the wrist back or curl it forward to move the dumbbell.
  3. Avoid elbow lockout: Keep a slight softness at the bottom rather than forcing the elbow fully straight.
  4. Control the alternation: Finish the lowering phase on one arm before starting the other to avoid rushing or swinging.
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