Seated Bent-Over Dumbbell Rear Delt Fly: how to do it right
In short: The seated bent-over dumbbell fly isolates the rear delt, loaded the most at mid-range of horizontal abduction.
How to do it, step by step
- 1Seated, torso bent toward your thighs, back braced and neutral, dumbbells under your legs.
- 2Elbows fixed in slight flexion: spread your arms out to the sides, not backward.
- 3Rise until your arms are parallel to the floor, without going past.
- 4Control the return without letting go, keep continuous tension.
- 5Slow, steady rhythm, no jerks and no momentum from the torso.
The mistake to avoid
Don't lift your torso off your thighs to go higher.
Other common mistakes
- Pulling your elbows backward recruits the back: keep the elbows fixed and spread out to the sides.
- Using momentum from your torso cheats the load: lock the trunk and move only the arms.
- Shrugging your shoulders toward your ears overloads the upper traps: keep your shoulders down and your shoulder blades stable.
- Going too heavy breaks the path: lower the weight to feel the back of the shoulder.
Muscles worked
- Main:
- Rear delts
- Supporting:
- Traps
The rear delt (the posterior head of the shoulder) is the prime mover: it pulls the arm backward in horizontal abduction. The mid and lower traps, along with the rhomboids, assist by bringing the shoulder blades together and stabilizing them. The infraspinatus takes a slight part in external rotation.
What to replace it with
Same muscle, same part of the movement: these exercises do the same job.
Frequently asked questions
How do I do the seated fly correctly?
Seated, torso bent toward your thighs, back braced and neutral, dumbbells under your legs. Elbows fixed in slight flexion: spread your arms out to the sides, not backward. Rise until your arms are parallel to the floor, without going past, then control the return without letting go. Slow, steady rhythm, no momentum from the torso.
How high do I raise my arms?
Rise until your arms are parallel to the floor, and no further: higher, the rear delt is shortened and the traps take over. At the bottom, control it without letting the dumbbells rest under you, tension is almost zero there and you'd lose all the benefit of the middle zone.
Where should I feel the fly?
You should feel the back of the shoulder, the rear delt, first. The mid and lower traps and the rhomboids assist by stabilizing the shoulder blades. If it burns mostly at the top of the traps, near the neck, you're shrugging: keep your shoulders down and go lighter.
What tempo on the seated fly?
Slow, steady rhythm, no jerks. Tension is highest at mid-range, arms halfway to horizontal, where the lever on the rear delt is longest. Don't look for a bounce at the bottom, stay continuous and controlled so you don't lose the load in that middle zone where it really counts.