Exercise movement reviewed by:Cody Lockling, MS, CSCS

How Iridium Programs This

Iridium cycles in this hammer-grip variation when sub-muscle fatigue analysis identifies that your brachialis and forearms are fresher than the biceps heads typically targeted by supinated movements. Because the preacher bench enforces strict isolation, the system closely monitors RPE trends to ensure progressive overload comes from muscular adaptation rather than momentum. This targeted volume is calculated to fit within your specific Maximum Recoverable Volume for the arms, ensuring accessory work does not impede recovery for heavy pulling sessions.

Form Cues

Sit with your armpits resting snugly over the top edge of the pad
Hold the dumbbells with palms facing each other in a neutral grip
Keep your triceps firmly planted against the bench throughout the set
Lower the weight slowly under full control
Squeeze the biceps and forearms hard at the top of the movement

Don't

Don't lift your elbows or triceps off the pad as you curl
Don't fully lock out your elbows at the bottom to avoid hyperextension
Don't use your body weight to rock the weight up
Don't let your wrists curl inward or drop downward

Common Mistakes

Lifting hips off the seat for leverage
Hyperextending elbows at the bottom
Rushing the lowering phase
Using a weight too heavy to control
Allowing wrists to rotate out of neutral position

Muscles Worked

This exercise primarily targets the brachialis (a muscle underneath the bicep) and the brachioradialis in the forearm due to the neutral hammer grip. It also works the biceps brachii, specifically emphasizing the long head, while the preacher bench setup eliminates shoulder assistance to ensure pure isolation.