Building wide, round shoulders is one of the fastest ways to change how your upper body looks.

Side delts play a huge role in creating that broad look and sharper V taper. If you want your shoulders to pop and your waist to look smaller, then training side delts properly is a must.

This post breaks down the three best exercises to start with and explains exactly why they work so well.

WHY SIDE DELTS MATTER

Your delts are split into three parts: front, side, and rear. The side delt is the one that gives your shoulders width. When it grows, it makes your upper body look broader and your waist slimmer. This creates that strong, athletic silhouette that stands out before anyone even looks at the details of your physique.

For most men, the side delts are what make the difference between average shoulders and a set that actually turns heads. They add to the roundness at the top of the arm and finish off the V taper. No matter if your goal is to look sharp in a t-shirt or to step on stage, strong side delts are a major piece of the puzzle.

LYING CABLE CUFF LATERAL RAISE

This is my number one pick for side delts. The key reason is how the cable loads the muscle. With dumbbells, the exercise is hardest at the top when your delts are at their weakest. With a cable, the resistance is greatest when your delts are at their strongest, in the mid to lengthened range. That is where you can produce the most force, which is the main trigger for muscle growth.

Lying on a bench also locks your body in place. You cannot swing the weight up using momentum from your hips, legs, or traps. This forces the side delts to do the work. Adjusting the cable height changes the line of pull so you can keep the tension exactly where you want it.

When doing this, think about moving your arm out to the side, not up. This keeps the load on the side delt rather than letting your upper traps take over. The result is a strict, controlled movement that targets the muscle in its strongest range and allows you to push it hard.

MACHINE LATERAL RAISE

The machine lateral raise comes second. It works on the same principle as the cable, keeping tension on the delts in the mid and lengthened range. Good machines are set up so you can align the pads with your arms or elbows. This means the resistance matches the strength curve of your delts and keeps the work exactly where it should be.

Another benefit is stability. The machine holds you in position and removes cheating from the movement. You can focus fully on pushing through your side delts without worrying about balance. This lets you train with more intensity and safely overload the muscle.

Different brands make different styles, but the main point stays the same. A quality lateral raise machine will load the delts in the strongest part of the range, making it one of the most effective tools for growing them.

SEATED OR CHEST-SUPPORTED DUMBBELL LATERAL RAISE

The dumbbell lateral raise is a classic. It has been used for decades to build shoulders. But compared to cables and machines, it has one drawback. The hardest point of the lift is at the top when your side delts are weakest. At the bottom, when your delts are strongest, the weight does not place much load at all. This makes it slightly less efficient for growth.

That said, it still works. Plenty of people have built impressive shoulders using dumbbells alone. The trick is to control the form. Sitting down or supporting your chest against a bench stops you from swinging the weights up with other muscles. This makes the movement stricter and keeps the focus where it should be.

If dumbbells are your only option, you can make them more effective. One approach is to use lighter weights and spend more time at the top half of the movement where the tension is highest. Another is to combine a set of lighter dumbbells for the full range with heavier dumbbells for partial reps in the top half. This way, you get the best of both worlds.

THE BIG PICTURE

All three of these exercises can grow side delts. The cable and machine versions get the edge because they load the muscle where it is strongest. The dumbbell raise comes in third but is still valuable, especially if equipment is limited.

In a normal shoulder workout, there is no need to do all three. Pick one based on what you have access to and train it hard. Push for progressive overload, adding weight or reps over time. Combine that with staying lean, and you will build the capped shoulders that set your physique apart.

REFERENCES

Burkholder, T.J., Lieber, R.L. (2001). Sarcomere length operating range of vertebrate muscles during movement. Journal of Experimental Biology, 204(9), pp.1529-1536. Available at: https://doi.org/10.1242/jeb.204.9.1529

Wakahara, T., Fukutani, A., Kawakami, Y., Yanai, T. (2013). Nonuniform muscle hypertrophy: Its relation to muscle activation in training session. Medicine and Science in Sports and Exercise, 45(11), pp.2158-2165. Available at: https://doi.org/10.1249/MSS.0b013e318299a6bb

Ackland, T.R., Elliott, B.C., Bloomfield, J. (2009). Applied Anatomy and Biomechanics in Sport. 2nd ed. Champaign, IL: Human Kinetics.