Chest Fly (Dumbbell)
The dumbbell chest fly is an isolation exercise performed on a flat bench that targets the pectoral muscles through a wide arc of motion. It focuses on stretching the chest fibers and building muscle definition by maintaining tension away from the body's midline.
Iridium classifies this movement as a hypertrophy accessory designed to accumulate middle chest volume without the high systemic fatigue of heavy pressing. The AI checks your per-muscle recovery status to ensure your anterior deltoids and pectorals can support the isolation load following recent sessions. To drive progress, Iridium analyzes RPE trends to increase volume safely rather than aggressively pushing 1RM strength on this lift.
Form Cues
- Retract your shoulder blades against the bench
- Maintain a slight, fixed bend in your elbows
- Lower the weights in a wide arc until you feel a stretch
- Squeeze your chest muscles hard at the top
- Keep your feet flat on the floor for stability
- Don't straighten your arms completely at the top
- Don't drop your elbows below shoulder level if it causes pain
- Don't turn the movement into a press by bending elbows too much
- Don't bang the dumbbells together at the peak
- Don't lift your head or hips off the bench
Common Mistakes
- Turning the movement into a press
- Locking elbows out straight
- Going too heavy and compromising form
- Overstretching the shoulder joint
- Using momentum to lift the weights
Muscles Worked
This exercise primarily isolates the pectoralis major, specifically targeting the sternal fibers to build chest width and inner-chest definition. The anterior deltoids and biceps play a secondary role by stabilizing the arm position and controlling the weight during the wide arc of movement.
Primary
Secondary
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