Smart shoulder solutions: an evidence-based approach to training the deltoids

The deltoid muscles, which form the musculature of the shoulders, are among the most important muscle groups in terms of the performance of both sports-related movements and activities of daily living. Whether your goal is to nail a volleyball or place items on an overhead shelf, or anything in between, strong shoulders are critical.

The shoulder is a complex ball and socket joint capable of flexion, extension, rotation and more, which 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 deltoids (figure). Many athletes 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 parts. Unfortunately, the resulting imbalance can sometimes lead to injury and dysfunction.

What the research reveals

Nasty determine which exercises best activate the shoulder muscles, ACE-sponsored research evaluated 10 exercises popular with athletes and the typical gym-goer alike. The researchers began by evaluating each of the 16 study participants‘ maximum one repetition (1-RM). seven out of 10 following exercises:

*1-RM was not collected for these exercises, which use body weight or rope as resistance.

During two subsequent training sessions, researchers placed electromyograph (EMG) electrodes on the three different heads of the deltoid muscle – the anterior, medial and posterior – and had participants perform five of the exercises during each session. For the exercises for which a 1-RM was determined, participants performed five repetitions at 70% of their 1-RM.

This is what they found:

• For the anterior deltoid, the dumbbell shoulder press produced the greatest amount of muscle activation.
• For the medial deltoid, the 45 degree incline row and the lateral raise with bent arms were the best.
• For the posterior deltoid, the seated lateral raise and the 45-degree incline row produced the greatest muscle activation.

The bottom line is that due to the complexity of the shoulder joint and the variety of movements possible at the shoulder, there is no single best exercise to train this muscle group. It is impossible to maximally activate all three heads of the deltoid muscle at once with a single exercise.

Additionally, it’s vital to understand which part of the deltoid muscle each exercise targets so you can balance the workout properly. For example, if a routine consists of dumbbell shoulder presses, lateral raises with bent arms, and the 45 degree incline row, the posterior deltoid is inadvertently neglected and the medial deltoid is doubled.

The researchers recommend that 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, noting that all three exercises are relatively effective at activating the medial deltoid muscle.

Finally, one last piece of advice from the researchers: it is best to start your training with exercises that target the posterior deltoid muscle, which is generally the weakest shoulder muscle, and then train the anterior deltoid muscle.

Expert advice

To give customers options, we asked two experienced ACE Certified Pros to tell us about their favorite shoulder exercises.

Man San Gilwho has been an ACE Certified Personal Trainer for 24 years, chose rotator cuff exercises and dumbbell shoulder presses as his favorite options. “Our rotator cuffs are often overlooked and inadequately trained” he explains. “Just something simple Internal/external shoulder rotation exercises can go a long way in maintaining the structural integrity of our shoulder and help prevent shoulder impingement and other injuries.”

Dumbbell shoulder presses are a great way to work the deltoids while engaging other parts of our body, such as the triceps, levator scapulae, trapezius and rhomboids, he explains. One word of caution: people with current shoulder problems may want to avoid doing overhead presses and instead perform lateral raises or front raises as needed.

Cindy SullivanACE certified personal trainer And Group fitness instructor, says that tWed from her favorite shoulder exercises for my midlife and senior clients are the barbell Sholder Press (sitting or standing) and Sholder Rbows (light weight or no weight).

To make the dumbbell shoulder press easier, use lighter weights (or none) and perform the exercise while seated for extra stability. To make it harder, add pace (slowly on the way down), hold the top, or do it standing with a staggered stance to activate the core.

Shoulder rainbows are ideal for clients working on mobility, posture and coordination, Sullivan explains. “I often use it with people who have limited range of motion or shoulder problems, especially if we relax the shoulder work without pushing too hard.”

To make this exercise easier, decrease the range of motion or perform without weights. To increase the challenge, add resistance (for example, light weights or small Pilates balls) and slow the movement for more control and time under tension.

Final thoughts

Variety in movements is essential when targeting a muscle group as complex as the deltoids. According to the ACE-sponsored study, a training program that includes the dumbbell shoulder press for the front of the shoulders and the 45 degree incline row or seated 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 move used in the ACE-sponsored study, including the first four listed below:

Also check out the links below for our expert suggestions and make sure you share all this information with your customers:

To see all 10 exercises evaluated in the study, Check this out downloadable pdf: Shoulder exercises.

	Corrective exercise (worth 2.5 ACE CECs): As an ACE Corrective Exercise Specialist, you will design programs for clients affected by chronic conditions or injuries, helping them regain daily function and move with confidence.
	Pain-free movement (worth 1.2 ACE CECs): As a pain-free movement specialist, you will better understand how pain affects movement and how you can create new strategies to help people move without pain.