Cable Shoulder External Rotation at 90°
The Cable Shoulder External Rotation at 90° is a targeted isolation exercise designed to strengthen the rotator cuff and posterior deltoid muscles. This movement improves shoulder stability and mobility by reinforcing the external rotation mechanics essential for overhead athletes and healthy posture.
Since the rotator cuff is small and easily fatigued, the AI's ability to track RPE and intensity is crucial for preventing strain in this delicate area. By analyzing your recovery data and daily readiness, the app can adjust volume to ensure you strengthen these stabilizers without overtraining them before heavy compound pressing. If you report shoulder impingement, the system remembers this pain association and can instantly suggest regressions like the arm-at-side variation to keep your joints safe.
Form Cues
- Keep your upper arm parallel to the floor throughout the set
- Maintain a strict 90-degree bend in your elbow
- Rotate your forearm back until it is vertical
- Keep your wrist neutral and firm
- Brace your core to prevent your lower back from arching
- Don't let your elbow drop below shoulder height
- Don't use momentum to swing the weight back
- Don't arch your lower back to complete the rep
- Don't allow your wrist to curl or extend
- Don't shrug your shoulder up towards your ear
Common Mistakes
- Dropping the elbow below shoulder level
- Using too much weight
- Compensating with lumbar extension
- Rushing the lowering phase
- Shrugging the traps
Muscles Worked
This exercise primarily targets the posterior deltoid and the critical external rotators of the rotator cuff, specifically the infraspinatus and teres minor. It also engages the rhomboids and middle trapezius isometrically to stabilize the scapula while the arm rotates in an abducted position.
Primary
Secondary
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