How to Do the Rear Delt Fly (Form & Benefits)

In an ideal world, we would be able to close our eyes and have our bodies look like Arnold Schwarzenegger’s.

Unfortunately, we live in the real world and we have to put in the time, work, and effort in order to reach our goals.

Deltoid muscles take time and commitment to grow and with an effective exercise routine, your goals can become reality. The rear delt fly is an exercise that can be performed with dumbbells to isolate and target those shoulder muscles that are often forgotten about. The exercise strengthens many of the upper body muscles but it mainly focuses on the deltoids.  

What Is a Rear Delt Fly?

A rear delt fly is an effective exercise that targets your deltoid muscles. Although it does work numerous muscles in the upper body, it mainly focuses on the shoulder muscles. The incorporation of upper body muscles not only improves performance in the gym but can also improve your quality of life by making functional, daily movements easier. 

This exercise can be incorporated into anyone’s workout routine whether you are seeking to be a bodybuilder, improve your fitness or simply want to change your boring upper-body routine. 

A rear delt fly is typically performed with a set of dumbbells

But you may also use a cable machine or a pec dec machine to raise weights to your sides in an arching motion.

Individuals with shoulder pain or injury should avoid doing this exercise unless they are working with a certified personal trainer who is monitoring the exercise. Individuals who have lower back pain may want to incorporate variations of this exercise that avoid the bent-over version to decrease the risk of injury and/or pain.

Training is an effective way to  protect yourself against injury but it is important that the training is designed for your needs and particular injuries. 

What Muscles Does a Rear Delt Fly Target?

Primary Muscles:

• Posterior Deltoids: You may also know the posterior deltoids as the rear delts. The posterior deltoids are one of the three main fibers of the deltoid muscle and they receive the most tension in this exercise. Strengthening your rear delts increases your upper body abilities athletically as well as daily to prevent injury.

Secondary Muscles:

• Trapezius: By strengthening the trapezius muscle, you are able to pull your shoulders back and stabilize the neck and upper back muscles to improve everyday movements.
• Rhomboids: By strengthening the rhomboid muscle, you are able to maintain good posture in order to prevent upper back pain.
• Erector spinae: The erector spinae is overlooked often but it plays a huge role in protecting and stabilizing the spine.

Benefits of Incorporating Rear Delt Fly Into Your Routine

1. Development of Stronger, Stable Shoulders

By engaging the shoulder muscles, they become stronger and more developed as time goes on. This exercise can also provide you with the extra strength needed to perform other exercises such as the overhead press or deadlift. In comparison to isolation exercises, this exercise is special as it works numerous upper-body muscles all at once.

2. Maintenance of Proper Posture

Our lives can often be filled with desk jobs and long commutes that cause us to hunch over and harm our posture. Poor posture may not seem like a big deal in the short run but constantly having bad posture will haunt you in the future. Not only will good posture prevent back pain and decrease the risk of injury, but  it also can improve your mental health and decrease fatigue. 

The rear delt fly combats this obstacle by adding muscle engagement in the upper body to tighten your upper back muscles and prevent hunched over shoulders. The exercise also targets the core muscles which aids in maintaining a straight back for proper posture.

3. Building Symmetry With The Shoulder - Improving Aesthetics

Well-developed shoulders contribute improving your overall body composition. Shoulder muscles need to be isolated and targeted, but once the muscle growth starts to show, your may may need to update your shirt collection.

How to Do the Rear Delt Fly (Form)

1. Grab hold of a pair of dumbbells with a neutral grip (palms facing inwards) in each hand and begin to bend at the hips and knees. Your torso should be parallel to the floor. 
2. Make sure your back is straight and keep a slight bend in your elbows. 
3. Begin to raise both of your arms out to the sides until the dumbbells are at shoulder height. 
4. Hold for a count of two then, with control, begin to lower the dumbbells to the starting position. 
5. Repeat this movement for the desired number of reps and sets.

Rear Delt Fly Tips and Common Mistakes

• Focus on keeping a neutral back: People tend to curve their spine when performing this exercise and this can lead to a lot of strain and pain in the lower back. 
• Do not bend your arms too much: It is important to keep those elbows slightly bent, but bending the arms too much can actually change the muscles targetted which is not the goal here.
• Do not straighten your elbows: On the other hand, straightening your elbows and not having any bend in the arms can be dangerous as locking out your elbows can lead to potential injuries in the joints.
• Do not lift too heavy: Weights that are too heavy can lead to altered reciprocal inhibition temporarily, and synergistic dominance in the long run which are two things that we would like to avoid all-in-all. It is a good rule of thumb to start off with a light weight then slowly move up to a heavy weights once you have executed proper form and are confident in the exercise. Proper form is crucial when it comes to preventing injury as well as effectively targetting the desired muscle groups.

Effective Rear Delt Fly Variations

1. Bent-Over Rear Delt Fly 

1. Find a bench and sit at the end of it with a pair of dumbbells in your hands. 
2. Bend from the hips with the dumbbells hanging on both sides. 
3. Begin to lift the dumbbells so they are at a level that is slightly higher than your shoulders. 
4. Slowly, lower to starting position. 
5. Repeat these steps for your desired number of reps and sets.

2. Machine Rear Delt Fly 

This exercise machine can restrict your range of motion as it provides more stability, decreasing your risk of injury.:

1. Sit down facing a rear deltoid machine. 
2. Place your chest against the backrest and grab ahold of the handles. 
3. Make sure your hands are directly in front of you with your arms stretched at shoulder level's height. 
4. Begin to pull the handles back as far as you can while maintaining proper form. Make sure your elbows are high and your arms are parallel to the floor. 
5. Return to the starting position by returning the handles directly in front of you.
6. Repeat these steps for your desired number of reps and sets.

3. Cable Rear Delt Fly 

1. Find a cable pulley and grab the handles by holding the left-side handle in the right hand and the right-side handle in the left hand. 
2. Stand in the middle of both handles and bend at your waist, never the lower back. Make sure your back is straight as well as parallel to the floor. 
3. Begin to raise your hands upward to shoulder level and make the cables cross over. 
4. Slowly, lower down the handles to the starting position.
5. Repeat these steps for your desired number of reps and sets.

4. One-Arm Rear Delt Fly 

1. Hold a left dumbbell in your left hand and lean forward at the hips. 
2. Place your right hand on your thigh. 
3. Begin to raise the dumbbell straight out to the side, ensuring that your left arm is parallel with the floor. 
4. Take a breath at the top of the movement then begin to lower the weight down to starting position.
5. Repeat these steps for your desired number of reps and sets then switch to the right side to ensure balance.

5. Lying Reverse Dumbbell Fly

1. Place two dumbbells on each side of a flat bench. 
2. Lie down with your chest on the bench and grab ahold of a dumbbell in each of your hands. You can spread your legs on the floor to provide yourself with extra support. 
3. While making sure you are keeping a slight bend in the elbows, begin to lift both of your arms out to the sides to shoulder height. 
4. Hold in this position for a count of two then slowly begin to lower the dumbbells to starting position. 
5. Repeat these steps for your desired number of reps and sets.

If you find that this exercise is too challenging or causes strain on your lower back, the use of an incline bench may overcome this issue. The next exercise explains how to effectively perform this modification.

6. Chest Supported Dumbbell Rear Delt Fly

1. Place dumbbells on each side of a bench. 
2. Set up the incline bench and lay down on it with your chest. 
3. Pick up the dumbbells in each arm and begin to raise your arms to the sides.
4. Make sure you squeeze your rear delts at the top to maximize engagement. 
5. Maintain a slight bend in the elbow to prevent them from locking out.
6. Hold in this position for a count of two then slowly begin to lower the dumbbells to starting position. 
7. Repeat these steps for your desired number of reps and sets.

7. Standing Reverse Fly With Resistance Bands

If you would like to gear away from machines or free weights, resistance bands are a great way to go. If you’re unsure as to what resistance bands to use or purchase, check out our advice on  the types of resistance bands and which one to get.

1. Stand up with a slight bend in your knees with your feet shoulder-width apart. 
2. Place a resistance band around any stationary post such as a squat rack. 
3. Grab hold of the resistance band in front of you slightly lower than the shoulder's height. 
4. Make sure to still maintain that slight bend in the elbows despite the fact that we are not using free weights. 
5. Squeeze the rear deltoid muscles to encourage engagement and open up the arms to the sides by pulling the resistance band apart. 
6. With control, return to the starting position and repeat
7. Repeat these steps for your desired number of reps and sets.

Final Verdict

It is easy to forget about the deltoid muscles but they play a larger role in your overall strength than you think. The incorporation of the rear delt fly or any of the variations you learned about above will lead you one step closer to your dreams and goals. 

It’s hard to say if we’ll be looking like Arnold anytime soon but we will be one step closer. Keep trying out different deltoid exercises until you figure out what works best for you and make sure you are getting your  protein stack in.