Holding a dumbbell in each hand, sit on a bench or chair.
Allow the dumbbells to hang down by your sides, palms facing in (neutral grip).
Keeping your torso upright and upper arms by your sides, exhale as you flex one elbow to raise the dumbbell up towards your shoulder. As you raise the dumbbell, supinate your forearm so that, by the end of the movement (or ‘curl’), your palm is facing your shoulder.
After fully flexing your elbow, you may move your elbow forward a little until your forearm is vertical.
Hold for a count of two and squeeze your biceps brachii.
Inhale as you slowly reverse the motion and return the dumbbell to the starting position.
Repeat the same movement with your opposite arm.
Repeat for the desired number of repetitions, alternating the arm that you use.
Comments and tips
Use the seated alternating dumbbell curl to isolate, strengthen, and build your elbow flexors. Being seated reduces your ability to cheat by using your legs and hips to build momentum.
Keep your body still. Only your forearms should move.
In elbow-flexion exercises, the position of the elbow and the type of grip used dictates which muscle is targeted. The biceps brachii acts as the primary elbow flexor when the forearm is supinated. Therefore, in order to fully emphasize the biceps brachii, the forearm must supinate as the elbow flexes.
If there are strength or size differences between your biceps, start the seated alternating dumbbell curl with your weaker arm and do not do more repetitions with your stronger arm, thus allowing your weaker arm to catch up.