Your rear delts, or posterior deltoids, is the back part of your shoulder muscle. It originates on the spine of your shoulder blade and inserts on your humerus (upper arm bone). It aids your lats in extending your shoulder, and also externally rotates your shoulder, together with infraspinatus and teres minor of your rotator cuff.
In this article, you will learn about rear delt muscle anatomy, what some effective rear delt exercises are, and how you can combine them into a workout.
Table of Contents
Rear Delt Muscle Anatomy
Your rear delts are one of three sets of muscle fibers in your deltoids, the other two being the front and lateral delts.
Your rear delts originate from the spine of your shoulder blade, partially covering your infraspinatus and teres minor, two muscles of your rotator cuff.
Your rear deltoid inserts on the outside of your upper arm, and it can thus both extend your shoulder (= bring your arm back, like in a row) and externally rotate it.
It is a synergist to your lats in shoulder extension and a synergist to infraspinatus and teres minor in external shoulder rotation.
The upper parts of your rear delts also abduct your arm.
Rear Delt Exercises
In this section, we’ll take a look at three of the best rear delt exercises. If you train one or two of these exercises, that’s all you need for a good rear delt workout.
1. Barbell Row
First up is the barbell row. While the barbell row hardly isolates the work to your rear delts, it still trains them. Besides, different variations of rows are likely already (or at least should be) part of your training program for a well-developed back, as they do a great job at laying the foundation of your back musculature.
You can increase the work put on your rear delts by taking a wider grip on the bar, and rowing slightly higher on your chest. Note that it will require you to use a lighter weight than in standard rows.
Possible substitutes:
2. Cable Rear Delt Row
In the cable rear delt row, you will be pulling your upper arms straight out to your sides. This will decrease the involvement of your lats, and isolate more of the work to your rear delts and traps.
A rope handle set high in a cable pulley works great for this exercise, but if you want to stick to free weights you can mimic the exercise by leaning forward and rowing in a similar motion with a barbell or a pair of dumbbells.
Possible substitutes:
3. Reverse Dumbbell Fly
Finally, the reverse dumbbell fly is as close as you’ll get to an isolation exercise for your rear delts, although it will train your middle traps as well.
Go very light and focus on form in this exercise. If you’re swinging the weights up by using your hip, it means that you’ve taken work away from your rear delts.
Possible substitutes:
- Reverse Machine Fly
- Reverse Cable Fly
Rear Delt Workout
So what does a good rear delt workout look like?
Well, first of all: depending on what exercises you already do for your back, you might already be training your rear delts well. Rowing and pulling exercises alone might not lead to optimal rear delt growth, but add in some reverse flyes and you’ve got them covered.
A specific rear deltoid workout could look something like this:
StrengthLog’s Rear Delt Workout
- Barbell Row: 3 sets x 8 reps
- Cable Rear Delt Row: 3 sets x 12 reps
- Reverse Dumbbell Fly: 3 sets x 15 reps
Together, these exercises will train your rear delts well, as well as provide training for other muscles in your upper back, such as your traps, rhomboids, and rotator cuffs. By combining different rep ranges (from low to high) it is also possible that you stimulate muscle growth via more mechanisms.
If you train these exercises with a good technique, and regularly try to increase the weight you are using while still maintaining good form, your rear delts are bound to grow bigger and stronger.
Wrapping Up
And that’s it! Hopefully, by now you have a good grasp of your rear delt muscle anatomy, what some effective rear delt exercises are, and how you can combine them into a rear delt workout.
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