The dumbbell hammer curl, also known as the neutral grip dumbbell curl, targets the muscles responsible for arm thickness and forearm development. This exercise uses a neutral grip to shift focus away from the bicep peak and toward deeper arm flexors. Incorporating the hammer curl builds comprehensive upper arm mass and improves overall grip strength. Mastering the correct technique ensures the intended muscles are fully engaged, maximizing effectiveness.
Executing the Standard Hammer Curl
Begin by standing with a dumbbell in each hand, arms hanging naturally at your sides. Use a neutral grip, with palms facing inward toward your thighs. Keep your feet shoulder-width apart and brace your core to maintain a stable foundation.
To initiate the lift, curl the dumbbells upward by bending only at the elbow. Keep your upper arms locked against your torso, ensuring the movement is smooth and controlled. Continue lifting until the dumbbells reach shoulder level and your forearm is fully contracted.
Pause briefly at the top before slowly lowering the weights back to the starting position. Resist gravity during the descent, taking two to three seconds to fully extend your arms and achieve a full range of motion.
Muscles Targeted by the Neutral Grip
The neutral grip alters muscle recruitment compared to a traditional underhand curl. This position emphasizes the brachialis, a muscle lying deep beneath the biceps. Developing the brachialis contributes significantly to the overall thickness and width of the upper arm.
The neutral grip also engages the brachioradialis, a long muscle running along the thumb side of the forearm. This muscle acts as an elbow flexor, contributing to forearm size and enhancing grip strength.
The biceps brachii remains active as a primary elbow flexor, with the neutral grip emphasizing the long head of the biceps. Targeting these muscles simultaneously provides a comprehensive stimulus for total arm development.
Avoiding Common Form Errors
One frequent error is using momentum, or “swinging,” to lift the weight. This happens when the weight is too heavy, forcing the lower back and hips to generate force instead of the arm muscles. Select a lighter dumbbell that allows you to maintain a stationary torso and lift using controlled muscle tension.
Another common mistake is allowing the elbows to float forward or away from the sides. When the elbows shift, the front shoulder muscles (deltoids) become engaged, reducing tension on the arm flexors. Pinning the elbows against the sides ensures the targeted muscles perform the work.
A lack of control during the lowering phase, or “skipping the negative,” is a missed opportunity for muscle growth. Ensure the descent takes at least two seconds, actively resisting the downward pull of gravity throughout the range of motion.