Rear Delt Fly
What is the rear delt fly?
The rear delt fly is an isolation exercise for the posterior deltoid (the back of the shoulder). Performed in a hinged-forward position with dumbbells, the trainee raises the dumbbells out to the sides, isolating the rear deltoid through a focused range of motion. For balanced shoulder development and posture, rear delt work is essential alongside front-deltoid-dominant pressing.
Who should do rear delt flyes?
Most lifters benefit from including rear delt flyes in their program. Pressing-dominant programs underdevelop the rear deltoid, producing rounded-shoulder posture and shoulder imbalances. Beginners and advanced lifters alike should include 4 to 8 weekly sets of rear delt work; the volume produces visible improvement in shoulder appearance and posture.
How do you program rear delt flyes?
Two to three times per week. For hypertrophy: 3 sets of 12 to 20 reps. The rear deltoid is small and responds well to high-volume work with light to moderate loads and strict form. Most programs include rear delt flyes alongside face pulls for complete posterior deltoid development.
Frequently asked questions
Should you do rear delt flyes seated or standing?
Both work. Seated removes the lower-back demand of maintaining the hinge; standing trains the lower-back endurance simultaneously. The seated version is often preferred because the trainee can focus exclusively on the rear delt rather than maintaining position.
Rear delt fly vs face pull?
Both train the rear deltoid. Face pulls additionally train the rotator cuff externally rotators; flyes do not. Most balanced programs include both for complete shoulder health and rear delt development.
How heavy should you go?
Light. Most trainees produce best results with 5 to 12 kilogram dumbbells. The rear delt is a small muscle; heavy loads break form and reduce isolation. Build to clean sets of 15 to 20 reps before progressing weight.
What about the reverse pec deck?
The reverse pec deck (machine rear delt fly) is excellent. The chest support eliminates stabilization demands and isolates the rear delt cleanly. Programs with access to the equipment often use it as the primary rear delt exercise.
Common mistakes
- Using too much weight and swinging the torso. Rear delts need precision.
- Rounding the back. Maintain a flat back during the hinge.
- Bringing dumbbells too far back behind the body. Stop at parallel to the floor.
- Pulling with the biceps. Lead with the elbows and squeeze the rear delts.
- Not feeling the rear delts. Check shoulder blade movement; if bent forward enough, the rear delts engage.
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