Single Arm Dumbbell Shoulder Press (How To, Muscles Worked)

The Single-Arm Dumbbell Shoulder Press strengthens the shoulders while also challenging your core and overall stability. Pressing with one arm at a time forces your torso to resist rotation and side bending, turning a classic shoulder movement into a full-body effort.

It’s a smart way to build shoulder strength and improve balance between sides.

Primary Muscles Worked: Deltoids (Primarily Anterior and Medial Heads)
Secondary Muscles Worked: Triceps Brachii, Core Stabilizers, Upper Traps
Equipment Needed: Dumbbell

How To Do DB Single-Arm Shoulder Press

Step-by-Step Instructions

Set-Up:
- Stand tall or sit upright on a bench without back support.
- Hold a dumbbell at shoulder height with your palm facing forward.
- Engage your core and keep your non-working arm at your side or on your hip for balance.
Execution:
- Press the dumbbell overhead until your arm is fully extended and your bicep is near your ear.
- Pause briefly at the top, then lower the dumbbell back to shoulder level with control.
- Complete all reps on one side before switching arms.
Tips for Proper Form:
- Keep your ribcage down and avoid leaning or arching your back—brace your core tight.
- Press in a vertical path—don’t let the weight drift forward or out to the side.
- If standing, keep your feet shoulder-width apart and knees slightly soft for stability.

Key Benefits

Builds shoulder strength and size while reinforcing proper pressing mechanics.
Improves core strength and stability through anti-rotation.
Helps correct muscular imbalances between left and right sides.

Modifications and Variations

Easier Option: Use a lighter weight or perform seated for more control.
Harder Option:
- Add a pause at the top of each rep.
- Perform from a half-kneeling position to increase core challenge.
- Use tempo (e.g., slow eccentric) to increase time under tension.

Common Mistakes

Overarching the Back: Keep your core engaged to protect your lower back.
Letting the Elbow Flare Too Wide: Keep your elbow just in front of the body in the press path.
Pressing Unevenly: Move in a smooth, straight line—avoid swaying or tilting to the side.

Reps and Sets Recommendations

For Beginners: 3 sets of 8–10 reps per arm with light to moderate weight.
For Strength: 4 sets of 6–8 reps per arm with heavier dumbbells and solid core control.
For Hypertrophy: 3–4 sets of 8–12 reps, focusing on controlled tempo and full range of motion.

Single Arm Dumbbell Shoulder Press Variations

Here are a few Single Arm DB Shoulder Press variations that only require a slight tweak and can all work perfectly to add a little variation to your workout program.

Dumbbell Shoulder Press

Most would actually consider Single Arm DB Press to be a variation of the more standard Dumbbell Shoulder Press. Either way, the simplest way to make a slight change to the single-arm version of the exercise is to press both dumbbells at once.

You will lose some of the core stability that comes with pressing with one arm at a time, but pressing with both arms at the same time will save you time and make your workout plan more efficient.

Seated DB Shoulder Press

The simplest variation to the Dumbbell Shoulder Press is to turn it into a seated movement – Seated Dumbbell Shoulder Press. This could be sitting freely on a bench or box or with a bench adjusted up to 90 degrees allowing the lift then brace against.

Pressing from a seated position helps eliminate the ability to cheat reps by using the legs and it works as a great alternative for anyone with a lower-body injury that prevents them from standing easily.

Obviously, this variation can also be done one arm at a time as well as a single-arm movement.

Alternating DB Shoulder Press

For this variation, press both dumbbells overhead. Leave one dumbbell overhead while you lower down and press the other. Continue alternating back and forth like this until all reps are completed – always leaving one dumbbell in the pressed-out position.

This variation works great because it creates a lot of time under tension and forces the shoulder to stabilize the weight in the overhead position.

Dumbbell Shoulder Press Alternatives

Looking to change up your workout a bit? Here are some great alternatives to try out.

Overhead Press

If you don’t have dumbbells but you have a barbell then I would suggest giving Overhead Press a try.

The Overhead Press is a barbell shoulder press from a standing position. It’s one of the best upper body movements for building mass and strength.

Landmine Single Arm Press

Push one end of your barbell into a corner or stable surface. Load the other end with some weight. I would recommend starting very light at first as you get used to this movement that is most likely new. Standing in an athletic position, perform single-arm presses with the “landmine”.

Kneeling Dumbbell Shoulder Press

Put one knee down and keep the other up. If your right knee is up, put the dumbbell in your left hand and knock out your presses. The Kneeling DB Shoulder Press is a great movement for novice lifters that need to progress their way through overhead pressing movements.