If you want to build strong, defined shoulders, you need to train all three heads. Learning how to do rear delt flys with dumbbells is the most effective way to target the often-neglected posterior deltoids. This exercise is crucial for balanced shoulder development and better posture, but only if you use the right technique.
Many people perform this movement incorrectly, using too much weight and turning it into a back exercise. This guide will walk you through the exact steps to master the form, ensuring you actually work the muscles you intend to.
How to Do Rear Delt Flys with Dumbbells
This section breaks down the standard bent-over dumbbell rear delt fly. We’ll cover the setup, the step-by-step movement, and common pitfalls to avoid.
Equipment and Setup
You only need a pair of light to moderate dumbbells. Choosing the right weight is critical here—this is an isolation exercise for a small muscle group. If you can’t control the weight with perfect form, it’s too heavy.
Find a clear space on the gym floor or use a bench. You can perform this exercise standing or seated, but we’ll start with the standing version as it’s most common.
Step-by-Step Instructions
Follow these numbered steps closely for each rep.
1. Grip and Stance: Pick up the dumbbells with a neutral grip (palms facing each other). Stand with your feet roughly hip-width apart for stability.
2. Hinge Forward: With a soft bend in your knees, hinge at your hips to lean your torso forward. Aim to get your torso almost parallel to the floor. Keep your back straight and core braced—do not round your spine.
3. Starting Position: Let the dumbbells hang directly below your chest, arms extended downward with a slight bend in your elbows. This bend should be fixed throughout the movement; don’t change the angle at your elbow joint.
4. The Fly Movement: Squeeze your shoulder blades together and lift the dumbbells out to your sides. Focus on leading with your elbows and the back of your shoulders. Your hands should travel in an arc, not a straight line.
5. The Top Position: Lift until your arms are roughly in line with your torso. Do not go higher, as this often engages the upper traps. At the top, you should feel a strong squeeze between your shoulder blades.
6. The Lowering Phase: Slowly and with control, lower the dumbbells back along the same path to the starting position. Resist gravity on the way down for maximum muscle tension.
Common Form Mistakes to Avoid
Watching for these errors will instantly improve your effectiveness.
* Using Momentum: Swinging the weights up with your body means the weight is too heavy. Each rep should be strict and controlled.
* Shrugging Shoulders: If your shoulders creep up toward your ears, you’re using your traps. Consciously keep your shoulders down away from your ears.
* Rounding the Back: A rounded spine puts your lower back at risk. Maintain a neutral spine from your head to your tailbone.
* Bending the Wrists: Your wrists should stay in a neutral, straight line with your forearms. Don’t let them bend downward as you lift.
* Pulling Too High: Lifting past parallel with your body shifts work away from the rear delts. The contraction at the top is subtle but powerful.
Rear Delt Fly Variations
Once you’ve mastered the basic form, you can try these variations to keep your training fresh.
Seated Rear Delt Fly
Sitting on the edge of a bench eliminates any chance of using leg drive or body english. It forces you to rely soley on your rear delts. Lean forward until your chest is near your thighs and perform the movement.
Incline Bench Rear Delt Fly
Lie face down on an incline bench set to about 30-45 degrees. This supports your chest and lower back, allowing you to focus completely on the squeeze. Let the dumbbells hang straight down and perform the fly.
Standing Cable Rear Delt Fly
Using a cable machine provides constant tension throughout the entire range of motion. Set the cable pulleys to about chest height, grab the handles, and perform the same hinged, flying motion.
Why Proper Form is Non-Negotiable
Getting the form right on rear delt flys isn’t just about building muscle; it’s about safety and function. Poor form can lead to shoulder impingement or lower back strain, setting you back for weeks.
Correct technique ensures the rear delts are the primary mover. This improves shoulder stability, counteracts the hunched-forward posture from daily life and chest training, and creates that coveted 3D shoulder look.
Programming Your Rear Delt Training
To effectively incorporate this exercise into your routine, consider these guidelines.
* Frequency: Train your rear delts 2-3 times per week. They recover relatively quickly.
* Rep Range: Aim for higher reps, typically 10-15 per set. This promotes muscle growth and endurance in smaller stabilizer muscles.
* Sets: 3-4 working sets per session is sufficient.
* Placement in Workout: Perform rear delt flys later in your shoulder or back workout, after your heavier compound lifts like overhead press or rows.
Remember, consistency with light weight and perfect form far outperforms sporadic heavy, sloppy sessions. Track your progress by how strong the mind-muscle connection feels, not just by the number on the dumbbell.
FAQ Section
What muscles do rear delt flys work?
The primary muscle worked is the posterior deltoid (rear shoulder). It also significantly engages the muscles of the upper back, specifically the rhomboids and trapezius, as stabilizers and synergists.
How heavy should the dumbbells be for rear delt flys?
Start much lighter than you think. The goal is a strong contraction and a controlled motion, not moving max weight. Most people find success with dumbbells between 5-20 pounds, depending on their strength level.
What’s the difference between a rear delt fly and a bent-over row?
A rear delt fly is a horizontal abduction movement, where you move your arms out to the sides with a fixed elbow angle. A bent-over row is a pulling movement, where you pull weight toward your torso by bending at the elbows. Rows work the larger back muscles more.
Can I do rear delt flys every day?
It’s not recommended. Muscles need time to repair and grow. Training them 2-3 times per week with at least one day of rest between sessions is a more effective strategy for long-term progress.
I feel it more in my back than my shoulders. What am I doing wrong?
This usually means you are retracting your shoulder blades (squeezing them together) too early and too aggressively in the movement. Focus on initiating the lift by thinking about moving from the back of your shoulder joint, not by pinching your shoulder blades together first. The scapular movement should be a natural consequence of the arm movement.
Are resistance bands good for rear delt flys?
Yes, resistance bands are an excellent tool for rear delt flys. They provide accommodating tension, meaning the resistance increases at the top of the movement where you are stronger. This can lead to a fantastic pump and is great for home workouts or warming up.
Mastering how to do rear delt flys with dumbbells is a game-changer for your physique and shoulder health. It requires patience and a willingness to prioritize technique over ego-lifting. Start light, focus on that mind-muscle connection, and be consistent. Over time, you’ll build stronger, healthier shoulders that look as good as they function.