Exercise movement reviewed by:Marie Braga, PT, DPT, CSCS

How Iridium Programs This

Iridium evaluates recent abdominal and hip flexor volume to determine if your core is sufficiently recovered for this compound movement. Because this exercise relies on body weight, Iridium tracks your rep count relative to your current weight to ensure consistent progressive overload. If your hip flexors show high cumulative fatigue from recent lower-body sessions, the AI may pivot your core training to less hip-dominant isolation exercises.

Form Cues

Draw your navel deeply toward your spine
Lift your head, shoulders, and hips simultaneously
Exhale sharply as your knees meet your chest
Squeeze your abs at the top of the movement
Lower your body slowly with control

Don't

Don't pull on your neck with your hands
Don't use momentum to swing your body up
Don't let your lower back arch excessively at the bottom
Don't hold your breath during the contraction

Common Mistakes

Pulling on the neck
Using momentum instead of muscle
Arching the lower back
Incomplete range of motion
Rushing the lowering phase

Muscles Worked

This exercise primarily targets the rectus abdominis, effectively engaging both the upper and lower regions by bringing the rib cage and pelvis together simultaneously. The hip flexors play a significant secondary role in drawing the knees toward the chest, making it a functional movement for overall core strength.