An Evidence-based Approach to Training the Deltoids
Provided by American Council on Exercise
Key Takeaways
Evidence-based workouts are the foundation of a
good resistance-training program. The shoulder exercises presented here will
develop both strength and function.
ACE-sponsored research compared muscle
activation of the anterior, medial and posterior deltoids when performing 10
different exercises.
To learn how to properly perform our recommended
shoulder exercises, check out the links provided in the Final Thoughts section
below:
o Dumbbell
shoulder press
o 45-degree
incline row
o Bent-arm
lateral raise
o Seated rear
lateral raise
o Rotator
cuff exercises (internal rotation and external rotation)
o Shoulder
rainbows
To see all 10 exercises evaluated in our research, check out this downloadable PDF: Shoulder Exercises
The deltoids, which make up the musculature of the shoulders, are among the
most important muscle groups in terms of the performance of both sport-related
movements and activities of daily living. Whether your goal is to spike a
volleyball or place items on an overhead shelf, or anything in between, strong
shoulders are vital.
The shoulder is a complex ball-and-socket joint capable of flexion,
extension, rotation and more, which is what makes training the deltoids so
complex. Anatomically, the deltoid is one large triangular muscle divided into
three parts (or heads) based on the attachment of the muscle's fibers the
anterior, medial (or middle) and posterior deltoid (Figure). Many exercisers
focus on the part of the shoulder they can see in the mirror while training
(i.e., the anterior deltoid) and neglect the medial and posterior portions.
Unfortunately, the resulting imbalance can sometimes lead to injury and
dysfunction.
What the Research Reveals
To determine which exercises best activate the shoulder
muscles, ACE-sponsored research evaluated 10 exercises
popular among both athletes and the typical gym-goer. The researchers began by
evaluating each of the study s 16 participants one-repetition maximum
(1-RM) on seven of the 10 following exercises:
|
Dumbbell
shoulder press
Push-up*
Cable
diagonal raise
Dips*
Dumbbell
front raise |
Battle
ropes*
Barbell
upright row
Bent-arm
lateral raise
45-degree
incline row
Seated
rear lateral raise |
*1-RM was not collected for these exercises, which use body weight or the
rope as resistance.
On two subsequent workout sessions, researchers placed electromyograph (EMG)
electrodes on the three different heads of the deltoid muscle the anterior,
medial and posterior and had the participants perform five of the exercises
during each session. For those exercises for which a 1-RM was determined, the
participants performed five repetitions using 70% of their 1-RM.
Here's what they found:
For the anterior deltoid, the dumbbell shoulder
press elicited the highest amount of muscle activation.
For the medial deltoid, the 45-degree incline
row and bent-arm lateral raise came out on top.
For the posterior deltoid, the seated rear
lateral raise and the 45-degree incline row provided the greatest muscle
activation.
The bottom line is that, because of the complexity of the shoulder joint
and the variety of movements possible at the shoulder, there is no one best
exercise for training this muscle group. It s impossible for a single
exercise to maximally activate all three heads of the deltoid muscle at one
time.
In addition, it s vital to understand which area of the deltoid each
exercise targets so that you can properly balance the workout. For example, if
a routine consists of dumbbell shoulder presses, bent-arm lateral raises and
the 45-degree incline row, it inadvertently neglects the posterior deltoid and
doubles up on the medial deltoid.
The researchers recommend people perform the dumbbell shoulder press for
the front of the shoulders and either the 45-degree incline row or the seated
rear lateral raise for the back of the shoulders, pointing out that all three
exercises are relatively effective at activating the medial deltoid, as well.
Finally, one last piece of advice from the researchers: It s best to begin
your workout with exercises that target the posterior deltoid, as that s
typically the weakest of the shoulder muscles, then follow up by working the
anterior deltoid.
Expert Advice
In the interest of providing options for clients, we asked two experienced
ACE Certified Pros to tell us about their favorite exercises for the shoulders.
Mann San Gil,
who has been an ACE Certified Personal Trainer for 24 years, chose rotator cuff
exercises and dumbbell shoulder presses as his go-to options. Our rotator
cuffs are often overlooked and undertrained, he explains. Just some
simple internal/external shoulder rotation exercises go a long way in
preserving our shoulder's structural integrity and help prevent shoulder
impingement and other injuries.
Dumbbell shoulder presses are a great way to work the delts while having
other parts of our body engaged, including the triceps, levator
scapulae, trapezius and rhomboids, he explains. One word of caution: People
with current shoulder issues may want to avoid doing overhead presses and
instead perform lateral raises or front raises as needed.
Cindy
Sullivan, ACE Certified Personal Trainer and Group Fitness
Instructor, says that two of her favorite shoulder exercises for my
midlife and senior clients are the dumbbell shoulder press
(seated or standing) and shoulder rainbows (light weight or no
weight).
To make the dumbbell shoulder press easier, use lighter weights (or none)
and perform the exercise seated for added stability. To make it more difficult,
add tempo (slow on the way down), hold at the top, or do it standing with a
staggered stance to engage the core.
Shoulder rainbows are ideal for clients who are working on mobility, posture
and coordination, Sullivan explains. I use it often with those who have
limited range of motion or past shoulder issues especially when we re easing
into shoulder work without pushing too hard.
To make this exercise easier, reduce the range of motion or perform without
weights. To increase the challenge, add resistance (e.g., light weights or
small Pilates balls) and slow the movement down for more control and time under
tension.
Final Thoughts
Variety of movement is essential when targeting a muscle group as complex as the deltoids. According to the ACE-sponsored research, a training program that includes the dumbbell shoulder press for the front of the shoulders and either the 45-degree incline row or the seated rear lateral raise for the back of the shoulders is effective for both sports performance and function. Also, consider adding our expert recommendations to the mix. Watch this YouTube video to learn how to perform each movement used in the ACE-sponsored research, including the first four listed below:
Also, check out the links below for our expert suggestions and be sure to
share all of this information with your clients:
Dumbbell shoulder press
45-degree incline row
Bent-arm lateral raise
Seated rear lateral raise
Rotator cuff exercises (internal rotation and external rotation)
To see all 10 exercises evaluated in the research, check out
this downloadable PDF: Shoulder Exercises.
Author
American Council on Exercise
Contributor