Prone I's
A floor-based isolation exercise that targets the lower trapezius and improves shoulder mobility by lifting the arms overhead in an I-shape. It strengthens the posterior chain to correct posture and support overhead stability.
Iridium treats Prone I's as a low-impact accessory movement, typically programming them when your systemic fatigue is high but your lower trapezius specific volume is below maintenance levels.
Form Cues
- Lie face down with arms extended overhead
- Keep your chin tucked and eyes facing the mat
- Engage your glutes to flatten your lower back
- Lift your arms by squeezing your mid-back
- Hold the top position for a distinct pause
- Don't shrug your shoulders up toward your ears
- Don't crane your neck to look forward
- Don't use momentum to swing the arms up
- Don't arch your lower back aggressively
Common Mistakes
- Overactive upper trapezius (shrugging)
- Hyperextending the neck
- Bending the elbows
- Lifting with the lower back instead of shoulders
Muscles Worked
This movement specifically targets the lower trapezius and middle trapezius, which are crucial for scapular depression and stability. It also engages the erector spinae isometrically to maintain a neutral spine and recruits the posterior deltoids to assist in the arm lift.
Primary
Secondary
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