How Iridium Programs This

Iridium tracks accumulated fatigue in the brachioradialis and forearm extensors to schedule this exercise so it does not interfere with grip-heavy pulling movements in your 7-day history. Since this is a unilateral movement, the algorithm also adjusts your session's volume projection to account for the extra time required to train each arm independently against your time constraints.

Form Cues

Stand tall with a neutral spine and brace your core
Grip the dumbbell with your palm facing down (pronated)
Pin your working elbow firmly against your ribcage
Curl the weight up slowly while keeping your wrist straight
Lower the dumbbell with a controlled, 3-second tempo

Don't

Don't swing your upper body to generate momentum
Don't let your elbow drift forward or flare out
Don't curl your wrist inward at the top of the movement
Don't drop the weight quickly during the lowering phase

Common Mistakes

Using excessive momentum to lift the weight
Allowing the wrist to go limp or bend excessively
Lifting the elbow away from the side
Using a weight that is too heavy to control

Muscles Worked

This exercise primarily isolates the brachioradialis (the large muscle on the top of the forearm) and the brachialis, which sits underneath the biceps. While the biceps are recruited, the pronated hand position mechanically disadvantages them, forcing the forearms to do the majority of the work for thicker lower arms.