Shoulders Exercise · Dumbbell
Biomechanical cues verified by the PlanWorkouts Science Review Board under CSCS editorial oversight; see our editorial standards.
The Dumbbell Rear Fly is a targeted isolation shoulders movement designed to train the Delts with direct engagement of the Rhomboids.
Single-joint horizontal adduction isolating the sternal and clavicular pectoralis fibers without triceps tricep fatigue limiting set termination. Executing this with strict form maximizes muscle fiber recruitment while protecting joint structures.
Quick Exercise Facts
Target Muscle Activation
The rear fly — bent over, arms sweeping out to the sides — isolates the rear deltoids and upper back stabilizers through a wide arc that most pressing and pulling movements skip entirely. Keeping a slight bend in the elbows and leading with the elbows rather than the hands keeps the tension on the rear delts instead of letting the upper traps take over. It's one of the more commonly under-programmed shoulder exercises relative to how much it helps posture.
How to Do the Dumbbell Rear Fly
- Begin standing with feet shoulder-width apart, holding a dumbbell in each hand.
- Bend your knees slightly and hinge forward at the hips, keeping your back straight.
- Extend your arms straight down toward the floor, palms facing one another.
- Keeping a slight bend in your elbows, lift your arms out to the sides and squeeze your shoulder blades together.
- Hold briefly at the top, then lower your arms back down under control.
- Repeat for your target rep goal, keeping your core engaged and avoiding any reliance on momentum.
Recommended Sets & Reps by Training Goal
65–75% 1RM · 60s rest
50–60% 1RM · 30–45s rest
Controlled 3s eccentric · 60s rest
Biomechanical & Joint Load Cues
Single-joint horizontal adduction isolating the sternal and clavicular pectoralis fibers without triceps tricep fatigue limiting set termination.
Common Mechanical Mistakes & Form Errors to Avoid
- Bending Elbows into a Press: Excessively bending elbows into 90 degrees during flyes turns the movement into a press, recruiting triceps instead of isolating pectorals.
- Overstretching the Shoulder Capsule: Dropping arms too far behind the torso plane strains the anterior capsule without adding meaningful pec activation.
- Rushing the Converging Squeeze: Failing to pause briefly at peak contraction in front of the chest misses the maximal short-muscle fiber recruitment.
Proper Breathing Patterns & Core Engagement
Inhale as arms open into full chest stretch; exhale as hands converge in front of the chest.
Add the Dumbbell Rear Fly to Your Custom Workout Routine
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Injury Modification & Joint Safety
Do not overstretch past comfortable range in the bottom position if you have a history of anterior shoulder subluxation or AC joint sprain. If joint irritation persists, immediately stop and substitute this movement with another exercise from the Shoulders exercises category.
Muscles Worked
The Dumbbell Rear Fly primarily targets the Delts, with Trapezius as the primary synergist muscle group, along with the Rhomboids.
More Shoulders Exercises
Band Front Lateral Raise
Band Front Raise
Band Reverse Fly
Band Shoulder Press
Band Standing Rear Delt Row
Band Twisting Overhead Press
More Delts Exercises
Band Y-Raise
Barbell Front Raise
Barbell One Arm Snatch
Barbell Rear Delt Raise
Barbell Rear Delt Row
Barbell Seated Behind Head Military Press
Equipment Alternatives
Don't have dumbbell? These target the same delts with different equipment.
FAQ
- What muscles does the Dumbbell Rear Fly work?
- The Dumbbell Rear Fly primarily targets the delts as the primary agonist. Synergist assistance is provided by the trapezius along with the rhomboids. Maintaining strict biomechanical alignment ensures maximal tension remains focused on the intended muscle fibers rather than shifting to surrounding stabilizer joints.
- What equipment do I need for the Dumbbell Rear Fly?
- The Dumbbell Rear Fly is performed using a dumbbell. Ensure all equipment is securely positioned with collars or safety pins locked before loading working sets. If you train in a home gym or minimal setup, explore our equipment-free and resistance band alternatives below.
- What is the most common form mistake on the Dumbbell Rear Fly?
- The most frequent error is bending elbows into a press: Excessively bending elbows into 90 degrees during flyes turns the movement into a press, recruiting triceps instead of isolating pectorals.. Controlling the 2 to 3-second eccentric lowering phase ensures maximal hypertrophic stimulus while shielding connective tissue.
- How many sets and reps should I perform on the Dumbbell Rear Fly?
- For muscle growth and density, execute 3 to 4 working sets of 10 to 15 controlled repetitions with 60 seconds rest, emphasizing a deep stretch and deliberate peak contraction on every rep.
- What's a good alternative to the Dumbbell Rear Fly?
- If you don't have access to a dumbbell, the Left Hook. Boxing targets the same delts using body weight instead. This alternative replicates the same joint angle and movement plane while allowing you to train effectively with different available gear. You can also substitute it seamlessly in our free Workout Plan Builder.