Dumbbell Back Fly
The Dumbbell Back Fly is a bent-over isolation exercise that targets the posterior deltoids and upper back muscles to improve posture and shoulder health. By raising dumbbells in a wide arc, you strengthen the muscles responsible for pulling the shoulder blades together.
Since the rear deltoids are small muscles that fatigue quickly, maintaining proper load is crucial to prevent momentum-based cheating. The AI analyzes your RPE and drop-off in performance to ensure you are using a weight that isolates the target muscles without straining your lower back. Additionally, by monitoring your recovery status and HRV, the app can adjust volume to prevent overuse injuries in the shoulder joint, which is particularly sensitive to cumulative fatigue.
Form Cues
- Hinge at your hips until your torso is nearly parallel to the floor.
- Maintain a neutral spine with your core braced tightly.
- Keep a slight, fixed bend in your elbows throughout the entire arc.
- Squeeze your shoulder blades together firmly at the top of the movement.
- Control the descent slowly to resist gravity.
- Don't swing your torso upward to generate momentum.
- Don't shrug your shoulders up toward your ears.
- Don't round your lower back or let your chest collapse.
- Don't straighten your arms completely or lock your elbows.
- Don't let the weights drop quickly during the lowering phase.
Common Mistakes
- Using excessive momentum to swing weights
- Standing too upright during the set
- Bending elbows too much (mimicking a row)
- Rounding the spine (kyphosis)
- Leading with the hands instead of elbows
Muscles Worked
This exercise primarily isolates the posterior deltoids, rhomboids, and middle trapezius, which are essential for scapular retraction and posture correction. Secondary engagement occurs in the upper trapezius and forearms, while the spinal erectors and core work isometrically to stabilize the bent-over position.
Primary
Secondary
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