For complete shoulder development, it is important to train the posterior shoulder head, or posterior deltoid muscle, or rear deltoid in a targeted manner. Yet many people often ‘forget’ this. Maybe because they don’t know whether to train this muscle group on shoulder or back day.
The pars spinalis, as also referred to as the posterior part of the three-headed shoulder muscle, is an auxiliary muscle in most back exercises. Some see this as a good argument not to train the muscle in a targeted manner. But the same argument could be used to not train your biceps directly.
THE IMPORTANCE OF TRAINING REAR DELTS
By not training the rear delts directly, your shoulders may lack thickness in the side view. But there are also functional reasons why you should not ignore this muscle. A complete shoulder development, so of all three heads (front, middle and back) is important to get stronger in the basic exercises for both back and chest. But also for injury prevention, because with strong back shoulders you prevent an imbalance in the shoulder joint. In short, make sure that the rear delts do not become a weak link.
If the rear delts are already being trained in a targeted manner, people usually opt for bent-over lateral raises (also called rear delt flyes or reverse flyes) and rear delt rows. Great exercises, but you don’t really isolate the rear delts with them. In fact, it’s your entire upper back that is trained: back of shoulders, the middle and bottom of the trapezius, and the rhomboid.
If you really want to train your rear delts in an isolated way, you have to perform the exercises mentioned in a specific way. And so we get the next selection of exercises, specific for the rear delts.
1. SINGLE-ARM REAR DELT ROW
This exercise is similar to the single-arm dumbbell row, but you move your arm in a significantly different way. The main point is external rotation of the shoulders, which means turning your elbow out a little and then bringing it back as far as possible, without moving your upper body. Bodybuilding coach Jeff Cavaliere demonstrates this in the video below. Get a good mind-muscle connection: think of that little muscle at the back of your shoulder.
You perform the exercise leaning, but rather a bit higher than on a bench, so for example on the back of a bench, or – if it is not busy in the gym – on a dumbbell rack.
2. INCLINE BENCH DUMBBELL FLY WITH LIMITED ROM
Bent-over dumbbell lateral raises are best done on an incline bench, because then you don’t have to stabilize your body during the exercise. In this way, your lower back in particular remains out of harm’s way. To optimally stimulate the rear delts, do the following:
1. Press your shoulders forward as far as you can throughout the exercise, as if you were scraping the floor with dumbbells;
2. Use a half to 2/3 range of motion (ROM). So don’t go completely parallel with your arms, but stop at an angle of roughly 45 degrees with the floor. This way you leave the back muscles largely untouched and you ensure constant tension on the rear delts.
With reverse flyes, you use a neutral grip as standard, with your palms facing each other. This appeals to your rear delts best for the given movement, as research by hypertrophy expert Brad Schoenfeld has shown.
3. REAR DELTOID CABLE RAISE
A tip from YouTube oracle Scott Herman: do cable raises in the following way for a better mind-muscle connection.
Bend forward until your chest is nearly parallel to the floor. Keep your shoulders in a neutral position, so don’t squeeze your shoulder blades together. And maintain a slight bend in your elbow throughout the exercise.
The crux of the exercise is twofold:
1. Pull the weight as far away from your body as possible and only then back;
2. At the end of the movement, rotate your wrist so that your thumb is pointing back if you were sticking it out (which you can also do to check). By rotating this you put extra emphasis on the rear delt.
4. REVERSE PEC DECK FLYE WITH LIMITED ROM
Reverse flying on a pec deck machine is one of the most popular exercises for the rear delts. But for this exercise too, it’s better to cut off a bit of the ROM (about 1/3) to isolate the back of your shoulders as much as possible. So don’t go completely horizontal with your arms, unless you prefer to make it an exercise for your total upper back. Press your shoulders forward as far as possible again.
5. SIDE LYING DUMBBELL REAR DELT FLYE
If you don’t have access to a pec-deck machine or cable station, do this exercise instead of conventional bent-over lateral raises (aka dumbbell rear delt flyes). Because you lie sideways on an inclined bench, you train the rear delts in a way that they must constantly offer optimal resistance. In the regular version with dumbbells you miss resistance at the bottom of the exercise.
6. FACE PULL
Face pulls are basically rear delt rows, but instead of toward your waist or stomach, you pull the resistance toward your face. This stimulates your rear delts in a unique and extremely effective way. But your lateral delts (middle shoulder heads), traps and rhomboids also get a kick out of it. The face pull is therefore not an isolation exercise for your rear delts, but in our opinion it is indispensable for the full development of these muscles, and actually for more depth (thickness) in the entire upper back.
Face-pulls also strengthen the rotator cuffs, the four small muscles that stabilize the shoulder joint. In this way, the exercise also contributes to the health of your shoulder joint and injury prevention.
7. 45 DEGREE INCLINE ROW
Like the face pull, the 45-degree incline row fits perfectly in a workout where you want to target both the middle and rear shoulder heads. In an EMG study (study with electrodes) a few years ago, this rowing exercise emerged as the exercise that activates the lateral delts the most. But because you lean forward, the rear delts are also well trained. For the rear delts, the 45-degree incline row turned out to be the second best exercise, after the seated rear lateral raise.
According to the guidelines of coach Mike Israetel average to advanced bodybuilders need 6-8 sets per week to give the rear delts minimal growth stimulus. This is in addition to the indirect work you do with your back exercises. If you completely isolate the rear delts, as in most of the exercises above, 6 sets are sufficient. If you do an exercise like face pulls, which also targets other muscle groups, you need to charge a little more volume – around 8 sets.
For optimal growth you need even more sets. Our advice: do 10-12 sets and increase the volume if you notice that the growth is stagnating.
You train a small muscle group like the rear delts preferably with lighter weights. In terms of number of repetitions, you aim for 8 to 15.
Training frequency becomes more important the more volume you do. Ideally, you should do no more than 5-10 sets per muscle group per workout. If you do 12 sets for the rear delts, it is therefore best to spread them over two training sessions (2 x 6 sets) or even three training sessions (3 x 4 sets) per week.