The dumbbell rear delt fly targets the posterior deltoid and upper back muscles with a bent-over reverse fly motion. It’s the most accessible rear delt exercise — no machine needed, just two dumbbells and space to hinge.
What it is
The dumbbell rear delt fly is a shoulder isolation exercise performed hinged over at the hips. The lifter holds two light dumbbells, arms hanging below the shoulders, then raises them out to the sides in a wide arc to shoulder level. The rear delt and upper back work together throughout.
Muscles worked
| Muscle | Contribution |
|---|---|
| Posterior deltoid | ~50 % |
| Rhomboids, mid-trap | ~30 % |
| Rotator cuff | ~15 % |
| Core (isometric) | ~5 % |
How to dumbbell rear delt fly: 5 steps
-
Hinge over
Feet hip-width, **hinge at hips to 45°,** dumbbells hanging below shoulders.
-
Brace
**Flat back, core tight, slight knee bend.**
-
Raise arms wide
**Raise dumbbells out to sides to shoulder height,** slight elbow bend maintained.
-
Peak squeeze
**Squeeze shoulder blades together at top.**
-
Controlled descent
Lower over 2 seconds to starting position.
How it differs from reverse pec deck
- Free weights instead of machine. No pec deck required.
- Hinged bent-over position. Reverse pec deck uses a seated position.
- Adds lower-back demand. Isometric back extension needed to hold hinge.
- Lighter loads. The hinge and dumbbells cap load below what pec deck allows.
Common mistakes
When to use this variation
Use dumbbell rear delt flys for balanced shoulder development and posture. Program 3 sets of 12-15 reps. Essential to balance the volume of front pressing work in most programs.
FAQ
How heavy?
Very light — 4-8 kg for most intermediate lifters. Rear delts respond to volume and mind-muscle connection more than weight.
Seated bent-over or standing hinge?
Seated bent over a bench reduces lower-back demand and lets you focus on the delts. Both work.
Dumbbell or pec deck?
Pec deck removes the lower-back demand and allows heavier loads. Dumbbell is accessible everywhere. Use both across the week.
Related exercises
- Reverse Pec Deck: machine version
- Face Pull: cable rear delt + rotator cuff
- Y Raise: rear delt with lower trap
- Cable Reverse Fly: cable version




