4 Best Side Delt Exercises to Build Boulder Shoulders

Everybody dreams of getting those boulder shoulders, and we train our delts hard, but many of us just don't seem to get anywhere.

What many people may not know is that there are three parts to the deltoid muscle, and when it comes to building those big shoulders, one is more important than the others.

The trick is working out the right part of your deltoids, which in this case is the side deltoid, otherwise known as the lateral deltoid.

Let's figure out everything you need to know about the best side delt exercises to build big shoulders.


The Anatomy of the Deltoids


As mentioned in our opening, the deltoids consist of three separate heads or parts.

Which one you work out makes a big difference in terms of growing bigger and stronger shoulders.

The three parts of the deltoids include the anterior deltoids, the posterior deltoids, and the lateral deltoids, which is what we are here to focus on today.

Let's take a quick look at each of the deltoid heads, so you're clear on exactly what they do.


Posterior Deltoids

Your posterior deltoids are also known as the rear deltoids, and this is the muscle found on the back of the shoulders. This muscle is important, as it helps you rotate your shoulder externally and extend it.

Whenever you move your arm behind you and upwards, that's your rear deltoid working.

It's an important muscle to strengthen as it helps to take some of the pressure off of your front and anterior deltoids, thus helping to prevent injuries from occurring.


Anterior Deltoids

We then have the anterior deltoids, otherwise known as the front deltoid.

This is an important muscle because it allows for medial or inward rotation, horizontal abduction or movement towards the body, and shoulder flexion.

They're important for several reasons, and doing a full shoulder day to help strengthen your anterior deltoids is always recommended.


Lateral Deltoids

Now, the muscle we are here to focus on today is the lateral deltoid, otherwise known as the side deltoid.

This may also be referred to as the lateral head of the deltoid muscle, and it's responsible for any kind of outward movement when you move your arm away from your body.

Whenever you lift your arm sideways and away from you, that's your side deltoid muscle working. It also helps with the inward rotation of the shoulder, making it one of the most important parts of your shoulder.

Not only is this a very important muscle in terms of functionality, but it also helps you build those big boulder shoulders.

If you want broad shoulders, it's the lateral deltoids that you need to work out. Let's move on and go over some important tips on how to strengthen those lateral deltoids in the safe way.


Building Big Shoulders The Right Way

We are going to talk about a wide range of exercises that you can do to help build those big shoulders, specifically by working out the lateral deltoids.

However, before we do that, we want to go over some invaluable tips on doing shoulder workouts, so you can get the most out of each one, without injuring yourself, all to achieve the biggest gains.


Lighter Could be Better

Lighter Could be Better

While it is technically true that lifting heavier weights may activate your muscles more, There are times when it may be beneficial to go a bit lighter. Sure, anywhere between 15 and 25 lbs is fine if you are doing rear delt raises, front raises, lateral raises, or anything else of the sort.

However, what you may never have considered is going a bit lighter, down to 10 lbs or even 5 lbs. Although it might sound counterintuitive, when you lift less weight, you can force your lateral deltoid to contract much more, perform more of the work, lift more of the weight, and ultimately be stimulated in a much bigger way.

If you want to build broad shoulders and gain muscle, that's the way to do it. Next time you're at the gym, try using those 5 lbs dumbbells to do some lateral raises and see how far you get.


More Weight Can Be Beneficial – When Done Right

If you are trying to get big lateral deltoid muscles, using heavy weights might seem like a great idea, but that's only the case if you do the right exercises and if you do them the right way, something that we are going to teach you below.

The issue however with trying to use weights that are far too heavy for lateral deltoid exercises is that you'll end up cheating.

What we mean by this is that you'll end up engaging other muscle groups, such as your lower back, your legs, your trunk, your torso, and everything in between, just to help you get that weight up into the air.

Of course, you don't want to target any other muscle except for the lateral deltoids, which means that going with super heavy weights may not always be the answer unless you're doing the proper exercise.

If you are going to use super heavy dumbbells to work out your lateral deltoids, there are a select few exercises that you want to focus on, with the abduction row being one of them.


Abduction is King

Abduction is King

Above we mentioned a word, abduction, which is a great type of exercise to help target your middle deltoids.

The number one job of the lateral deltoid is to abduct the shoulder, which means that any exercise you do to grow your lateral deltoid needs to involve moving your arm up and away from your body, preferably sideways.

Yes, pushing motions such as overhead presses and bench presses also help grow your lateral deltoids, although rowing motions and lateral raises work well too.


Mistakes to Avoid with Side Deltoid Exercises

Just like there are some big tips for you to follow to do lateral deltoid exercises the right way, for those big shoulders, there are also some crucial mistakes that you need to avoid.

These are beginner mistakes, and with just a bit of effort, you can avoid all of them.


Shrugging Your Shoulders

One of the biggest mistakes that people make when doing lateral deltoid exercises is to shrug the shoulder, which ends up activating your trap or trapezius.

This happens because you'll try to lift a dumbbell that's too heavy, and once you get to a certain height, you can't lift it any higher, which means that your lateral deltoids don't have the strength for the full movement.

What people therefore end up doing is engaging the trapezius muscles and shrugging the dumbbells up to where they should be, which ends up activating your traps more than anything else.

This can cause shoulder pain and injury, and at the very least, just doesn't fully activate your deltoids.

Related: Muscles worked by upright rows.


Leaning Over

Another big mistake that people make when doing side deltoid exercises, particularly lateral raises with heavy dumbbells, is leaning to the front or in the opposite direction. Leaning in the opposite direction is an attempt to balance and use your core to get that dumbbell up.

However, if you're doing this, you're not abducting the arm at all, but instead are engaging your elbow. If you find this happening, use a lighter weight and focus on form over everything else.


Rotating Externally

The third big mistake that many beginners make when trying to exercise the side deltoids is external rotation. Most often, the issue with lateral raises, especially if someone is bent over, is that you end up rotating your shoulder externally.

This is because at the top of the movement, particularly if you're bent over, your shoulders will have to rotate externally to get the weight up to its peak position.

External rotation is not necessarily a bad thing if you're targeting other parts of the shoulders, but not for your middle deltoids. Once again, abduction is king, and this should be your main focus.


The 4 Best Lateral Deltoid Exercises to Grow Bigger Shoulders

What we want to do now is provide you with a list of the best lateral deltoid exercises so you can grow bigger shoulders.

Let's get to it and take a look at some of the best lateral deltoid exercises to grow bigger muscles.


The Lateral Raise

The Lateral Raise

We're starting with a classic side delt exercise, the lateral raise. This is otherwise known as the side delt raise. This is the number one exercise to target your side delts specifically, as it involves moving your arm sideways and upwards away from your body.

It's also an exercise that focuses on increasing the range of motion of your lateral deltoid. It's a great exercise to increase both the size and flexibility of your shoulders.

Start by standing upright with your hands at your sides. Hold a pair of dumbbells, starting with light ones, just 5 lbs to see how it feels. You're going to use a neutral grip, which means that your palms face inwards towards your body.

Slowly raise your arms upwards laterally until they are fully extended outwards from your body while keeping your back straight and your elbows locked. By keeping your arms straight, most of the tension should be in your side delts. Do 8 to 12 reps of this, and try to do at least three sets.

You can also use cables to perform lateral raises and this is one of our top choices for cable shoulder exercises.


Full-Range Lateral Raise

If you go to the gym, you might see people doing what looks like making a snow angel but standing up. Some people may refer to this exercise as angel wings, weighted jumping jacks (without the jumping), or most commonly, a full-range lateral raise.

If you are looking to target your lateral deltoids, as well as your front deltoids, and you want to increase your range of motion, then doing this exercise is great. This is one of these exercises we're starting with a very lightweight, just 5 lbs, as it’s more than enough for you to feel the burn.

Start by holding a pair of 5 lbs dumbbells in a reverse grip, which means that your hands should be facing away from your body with your palms facing forwards.

Starting with your arms down at your sides and your palms facing forwards, slowly raise your arms, just like in the lateral raise, but instead of stopping when your arms are horizontal, continue the exercise until they are fully extended up above your head.

Try to do this movement as slowly as possible, hold at the top, and then very slowly return down to the starting position, allowing yourself to feel as much of that burn as possible. While you do this exercise, make sure that your palms always face forward and away from your body.


Seated Arnold Press

When it comes to building boulder shoulders, Arnold Schwarzenegger had some of the best in the business. So what better exercise to do than the seated Arnold Press to develop coconut shoulders. It is similar to a dumbbell shoulder press but is modified with rotation to improve activation and mobility of the shoulders.

Start with a relatively light dumbbell, no more than 10 lbs. Seated, hold the dumbbells with your arms bent by your sides with the palms facing towards your chest.

Then rotate your arms out so your palms are now facing forward while simultaneously pressing the weight to raise it above your head like you would in a shoulder press.

Then reverse the previous steps back to the starting position. and aim to complete 10 to 12 reps.

Related Post: What Muscles Does Overhead Press Work?


The Abduction Row

Whereas all of the other exercises we've looked at today involved using relatively light weight, here we're talking about the abduction row, and here you can increase the weight quite a bit.

If you're a beginner, start with about 20 lbs, but if you've already got a good bit of shoulder strength, you should be able to manage 30 lbs have you been 40 lbs with ease.

Many people might not think of rowing as being a good exercise for the deltoids, but in reality, it's actually one of the best things you can do, especially if you want to use a heavyweight.

Your middle deltoid, when you are rowing, can handle a fair amount of weight, with a bit of help from the rear deltoid, although the main focus will still be on your lateral deltoids here.

Now, instead of just rowing, you will also be abducting, which is what really helps to target the lateral deltoids, while also minimizing how much your lats contribute to the movement. This makes the abduction row a great exercise to target your side deltoids specifically.

To do the abduction row, start by standing with your feet shoulder-width apart. Although you could technically do both arms at once, we recommend starting with a single arm, so you can really focus on proper form and motion.

Holding a dumbbell of an appropriate weight for your fitness level with an overhand grip, lean forward at roughly a 30° angle. For those of you who don't know, an overhand grip means that your palm should be facing backwards or towards your body.

Start by doing a normal row by using your shoulders to lift the dumbbell, but as you raise the dumbbell, also abducted, which means rotating your arm outwards so that your knuckles face outwards and your palms face inwards.

By combining both the abduction and the rowing motion, you serve to target the lateral deltoids in a really big way, making this by far one of the most effective lateral deltoid exercises on the list.

Related: Exercises to Target the Lower Traps


Best Side Deltoids Exercises – Final Thoughts

Best Side Deltoids Exercises

As you can see, there are plenty of exercises that you can do to grow those side deltoids. Of course, if you're looking to grow bigger shoulders in general, you also need to target both your posterior and anterior deltoids.

To this end, you could do other exercises such as the accommodating front delt raise, the dumbbell pressout, the rear delt row, and bodyweight back widows. With that being said, the four exercises we've discussed today are by far the best in terms of growing big boulder shoulders and increasing the size of your lateral deltoids.

Author's Photo

William Parrett

Will, co-founder of Home Gym Supply, launched the company in 2019 after 15-years in the fitness industry. His expertise stems not only from his professional background but also from his athletic pursuits. A former competitor in the World Beauty Fitness & Fashion (WBFF) and a competitive rugby player, Will has always been dedicated to health and fitness.