Muscles worked
What the dumbbell rear delt fly trains
Tap a muscle to see just that one and what it does in the lift.
Before the first rep
How to set up
- 01
Pick light dumbbells. Choose a weight you can lift for at least 10 clean reps without swinging. The rear delts are small, and going too heavy at first is the most common mistake.
- 02
Hinge forward. Stand with feet hip width, soften your knees and push your hips back until your torso is close to parallel with the floor. If you can't get that low with a flat back, stop around 45 degrees or use the bench version. Keep your neck in line with your back.
- 03
Let the weights hang. Hold the dumbbells with palms facing each other and let them hang straight under your shoulders, just short of touching.
- 04
Set your elbows. Put a slight bend in your elbows and keep that same bend for the whole set.
- 05
Or use a bench. If your lower back gets tired, lie chest down on a bench set to a low incline and let the dumbbells hang from there. The form is the same.
Step by step
How to do the dumbbell rear delt fly
- 01
Brace. Take a breath, tighten your stomach and lock in your hinge so only your arms will move.
- 02
Sweep out. Raise the dumbbells out to the sides in a wide arc, leading with the backs of your hands rather than pulling with your elbows.
- 03
Finish level. Stop when your upper arms are about in line with your body, roughly level with your shoulders. You should feel it in the back of your shoulders, not your neck.
- 04
Pause. Hold the top for a moment. Your shoulder blades can move a little, but your arms should do the work, not a hard pinch of your back.
- 05
Lower slowly. Take about two seconds to bring the dumbbells back under your shoulders, then start the next rep without letting them swing.
Cues to say in your head
- Chest still, arms move
- Reach wide, not back
- Keep the elbow bend
- Shoulder height, then stop
- Pause at the top
- Slow on the way down
Fix these first
Common mistakes
Going too heavy and swinging
Drop the weight until you can raise it without your torso bobbing. If you need momentum, your lower back and legs are doing the work instead of your rear delts.
Turning it into a row
Keep the same slight elbow bend from start to finish. Bending more as you lift pulls the elbows back and shifts the work to the lats and mid back.
Standing up as you lift
Hold your hinge angle for the whole set. Rising up turns the move into a lateral raise for the side delts.
Shrugging toward your ears
Keep your neck long and your shoulders away from your ears. If you feel it in your upper traps, go lighter.
Rounding your back
Keep a flat back with your chest open. If you can't hold the hinge, switch to the chest supported bench version.
Dropping the weights
Lower under control over about two seconds. The lowering half is a big part of the work.
Stay safe
Use weights light enough that you never have to jerk them up, and keep your back flat; if your lower back tires before your shoulders, do the fly lying chest down on an incline bench. To end a set, lower the dumbbells under control back under your shoulders, then stand up or set them down. Stop if you feel sharp or pinching pain in the front or top of the shoulder, and get it checked if it keeps coming back.
Programming
Sets, reps and how much weight
| Goal | Sets | Reps | Load | Rest |
|---|---|---|---|---|
| Muscle | 3 to 4 | 10 to 20 | 55–72% 1RM | 1 to 2 min |
| Endurance | 2 to 3 | 15 to 25 | 40–60% 1RM | 45 to 90 sec |
| Technique | 2 to 3 | 12 to 15 | 40–55% 1RM | 1 min |
Plan your next session
Put in a recent set. You get working weights for your goal, a warm-up and the plates to load.
Estimated 1RM 216 lb
Endurance sets
86–129lb
2 to 3 sets of 15 to 25 reps, 45 to 90 sec rest. Good as a finisher or for posture work. Keep the pace slow and steady.
Estimates use the Epley formula and work best from sets of 3 to 8 reps. Treat them as a starting point and adjust by how the first working set moves.
Questions
Dumbbell Rear Delt Fly questions
What muscles does the rear delt fly work?
Mainly the rear delts, the back part of the shoulder. Your mid traps and rhomboids help move your shoulder blades, and your lower back and hamstrings hold you in the bent over position.
Is the reverse pec deck the same as a rear delt fly?
It's the machine version of the same movement. You sit facing the pad and sweep the handles back, which supports your torso so you can focus on the rear delts.
How do you do a cable rear delt fly?
Set two pulleys at about shoulder height, grab the left cable with your right hand and the right cable with your left hand, then sweep your arms out and back with a slight elbow bend. Keep your chest still and stop when your arms line up with your body.
How do you do a band reverse fly?
Hold a light band in front of you at shoulder height with both hands and a slight bend in your elbows, then open your arms out to the sides until they line up with your body, keeping your shoulders down. The band pulls harder as your arms open, so return slowly instead of letting it snap your hands back together.
How heavy should rear delt flys be?
Light. Pick a weight you can raise for 10 to 20 reps without swinging or shrugging; for most people that is a light pair of dumbbells.
Should I squeeze my shoulder blades together on a rear delt fly?
A little movement is natural, but don't lead with a hard pinch. If the rep starts by squeezing your shoulder blades, more of the work tends to shift to your mid back and away from the rear delts.
Train in Protocol
Log your dumbbell rear delt fly by voice. Protocol tracks the rest.
Your last session shows up before every set, warm-ups and plates are worked out for you, and your coach sees every lift next to your sleep and recovery.