My right side has always been much stronger than my left, so I have to work hard to address the weaknesses between my two sides. One of my favorite upper body exercises to do to help strengthen my left side is the single-arm dumbbell bench press.
What is the single-arm dumbbell bench press? The single-arm dumbbell bench press is a variation of the dumbbell bench press in which you press one arm overhead at a time. It has greater demands on balance and stability than a regular dumbbell bench press because your body has to resist the urge to rotate on the bench.
The single-arm dumbbell bench press is a fantastic exercise, but before you try it, it’s important to understand why single-arm work is beneficial and how to perform the movement correctly. In this article, you’ll learn:
- How to perform the one-arm dumbbell bench press
- What muscles are worked with the single-arm dumbbell bench press
- The pros and cons of the single-arm dumbbell bench press
- Common mistakes when doing the single-arm dumbbell bench press
- How to program the single-arm dumbbell bench press
- Who should do the single-arm dumbbell bench press
Table of Contents
Single-Arm Dumbbell Bench Press: Overview
The single-arm dumbbell bench press is a bench press exercise in which you work one arm at a time. Your non-working arm stays overhead or out to the side to help you maintain tightness in your upper body and to help you keep your balance on the bench.
Doing unilateral work is beneficial for addressing strength imbalances, improving balance and coordination, and improving core stability. And not only can unilateral training aid in rehabbing existing injuries, it can also prevent new ones by helping make your right and left sides more symmetrical.
However, the single-arm dumbbell bench press is challenging for many people because it:
- Exposes strength imbalances between your right and left arms
- Is taxing on the core, which has to work harder to stabilize your body on the bench
- Requires you to use less weight than you’d use for other bench press variations
Single-Arm Dumbbell Bench Press: Muscles Worked
The muscles worked in the single-arm dumbbell press are the:
- Pecs
- Triceps
- Anterior deltoids
- Rotator cuff
- Core
The pecs and triceps do the majority of the work. The pecs are the primary driving force behind the upward pressing motion while the triceps assist with the extension of your elbow and the lockout.
The anterior deltoids are the primary muscle group in the shoulders that are involved in the single-arm dumbbell bench press. They assist with shoulder flexion, or the ability to move your arm over your head. The rotator cuff acts as a stabilizer and helps move your shoulders through their full range of motion.
During the one-arm chest press, your core’s job is to prevent you from either leaning into the weight or trying to move away from it. It also works to stabilize your body and keep it from falling off the bench.
Want to learn more? Check out our complete guide on the Muscles Used In The Bench Press.
How To Do the Single-Arm Dumbbell Bench Press
The single-arm dumbbell chest press isn’t an advanced movement, but it still requires proper technique to ensure you’re not putting yourself at risk of injury.
Step 1: Set Yourself up on the Bench
Sitting on a bench, rest a dumbbell on your thigh, then bring it up to your shoulder. Slowly lay down on the bench and keep the dumbbell at your shoulder with a neutral grip.
You can also keep your arm at about a 45° angle, but I don’t recommend bringing the dumbbell out any further than this because it will put your shoulder in a compromising position.
Step 2: Dig Your Feet into the Ground and Arch Your Back Slightly, Drawing Your Shoulder Blades Down and In
Like you would do in a regular bench press, you’ll want to maintain a slight arch in your back, though it doesn’t have to be as pronounced as an arch you would use for a barbell bench press. Keep your feet planted firmly on the ground and retract your shoulder blades.
Step 3: Hold Your Non-Working Arm Either Straight Up Overhead or Out to the Side
By not letting your non-working arm dangle off the side of the bench or resting your free hand casually on your stomach, you’ll be better able to maintain tension in your entire core and upper body.
Step 4: Brace Your Core
Bracing your core during any kind of bench press exercise is important because it creates stability and helps you control the weight, which is more difficult to do when you’re only using one arm.
To brace your core, take a deep breath to fill your lungs with air and expand your stomach. Increase the pressure in your midsection by clenching your abs, and hold your breath until you’ve completed the rep.
Step 5: Push the Dumbbell Overhead
Maintaining the tightness in your upper body, press the dumbbell overhead until your arm is straight but not completely locked out. Resist the temptation to rotate to one side. Hold the dumbbell overhead for a second; don’t just let it drop back down to your shoulder as soon as your arm is straight.
Step 6: Lower the Dumbbell in a Controlled Fashion
Slowly bring the dumbbell back down to your shoulder, remembering to maintain a neutral grip or keep the dumbbell at a 45° angle.
Take a deep breath and re-brace your core, then start over with step #1. Complete all reps on one side and do an equal number of reps on the opposite side.
5 Pros of the Single-Arm Dumbbell Bench Press
Five benefits of the single-arm dumbbell bench press are:
- It challenges your core more than regular dumbbell bench presses
- It helps prevent strength imbalances
- It improves your shoulder stability
- It provides a greater range of motion than barbell bench presses
- It helps prevent overtraining in your dominant side
1. It Challenges Your Core More than Regular Dumbbell Bench Presses
The offset loading of the single arm dumbbell bench press requires your obliques to work harder to prevent your body from rotating. This makes it an excellent anti-rotation exercise that improves the efficiency with which your core can stabilize your spine.
Check out two other anti-rotational exercises we’ve discussed:
- Jefferson Squat: How-To, Benefits, Should You Do It?
- 1 Arm vs 2 Arm Kettlebell Swing: Pros, Cons, Which Is Best?
2. It Helps Prevent Strength Imbalances
You don’t always notice asymmetries when doing standard bench presses because your stronger side compensates for the weaknesses in the other side. Even when you do bilateral dumbbell bench presses, there’s still an even amount of loading on both sides.
Doing unilateral work can help expose any imbalances you may have and help improve the strength in your weaker side.
3. It Improves Your Shoulder Stability
Rotator cuff injuries are common in athletes. To help prevent damage to these small but important tendons and muscles, it’s important to strengthen them and the other muscles that surround them.
1-arm dumbbell bench presses force you to concentrate on keeping your shoulder blades retracted. This prevents you from putting excess strain on your joints and allows you to move more efficiently.
If you’re looking to challenge your shoulder or overhead stability even more, you can also hold a dumbbell in the air with your non-working arm while you complete all of your reps on the working side.
4. It Provides a Greater Range of Motion than Barbell Bench Presses
With a barbell bench press, you can only bring the bar down so far before it reaches your chest and can’t go any further. The single arm dumbbell chest press allows you to bring the weight down a bit further, and that increased range of motion contributes to strength and hypertrophy gains.
With that said, you want to avoid bringing the dumbbell down too far as it can cause excess stress on your shoulders, as I’ll talk about below.
If you work out at home and don't have full equipment, check out our article on dumbbell chest exercises without a bench.
5. It Prevents Overtraining in Your Dominant Side
If you only ever do barbell bench presses, your stronger side will work harder to compensate for the areas in which your weaker side lags behind. This is known as the bilateral deficit. In a bilateral deficit, one side of your body fails to produce as much force as it should during certain activities.
By working just one side of your body at a time, you can overcome this deficit and train all of the necessary upper body muscles to fire properly the next time you do a bilateral movement. This will ensure that both sides of your body do an equal amount of work so you’re not constantly favoring one side, which can lead to overuse injuries.
3 Cons of the Single-Arm Dumbbell Bench Press
1. You Can’t Use Much Weight
I often find that the weight I use for a one-arm dumbbell press is lower than my regular dumbbell bench press. This is because of the offset loading and the greater stability demands it places on your body. Even when you do a bilateral dumbbell bench press, each side counterbalances the other and you can usually press heavier weight.
2. You Can’t Rush Through the Movement
A single arm dumbbell press isn’t a movement that you should speed through. Doing them slowly will allow you to engage all of the proper muscle groups and maintain the stability and control you need to perform each rep effectively.
However, this means it will take you longer to get through each set, which can be challenging for people who don’t have a lot of time to spend in the gym.
3. You May Find It Difficult to Do an Equal Number of Reps with Each Arm
Doing unilateral work means there’s no chance for your stronger side to compensate for the lagging strength on your weaker side. It can be frustrating if you can do 12 or 15 reps with your dominant arm and only 7 or 8 with your non-dominant arm.
When I’m doing single-arm work, I always start with my non-dominant side, which tires out much more quickly than my dominant side. This way, I can match the number of reps on my stronger side and ensure I’m doing the same amount of volume on each arm.
Check out Does Dumbbell Bench Press Help Your Barbell Bench Press?
Common Mistakes of the Single-Arm Dumbbell Bench Press
While the one arm dumbbell press isn’t a difficult movement to perform, it is essential that you do it correctly. Below are some of the most common mistakes seen in the single-arm dumbbell bench press.
1. Not Keeping Your Hips on the Bench
It’s common for the hips to come off the bench as you’re pressing the weight up, especially if it’s too heavy for you to manage. This not only places a lot of pressure on your lower back but it also prevents you from being able to use an effective leg drive.
Furthermore, you’re cheating the movement because it decreases the range of motion and makes it easier for you to get the weight all the way up.
2. Flaring Elbows Out to the Side
Elbow flare is a common mistake of bench presses in general. Doing this puts your shoulders in a suboptimal position and places an excess amount of strain on them.
A lot of exercise tutorials online will tell you to keep your palm facing forward when doing the one-arm dumbbell bench press, but doing this makes it easier for your elbows to flare. A more ideal way to perform the movement is to use a neutral grip or keep the dumbbells at about a 45° angle so your hands are turned in ever so slightly.
This will help you keep your elbow closer to your body and engage more of your pecs and triceps while reducing stress on your shoulder.
3. Bringing the Dumbbell Too Low
While one of the benefits of the single-arm dumbbell bench press is an increased range of motion, it is possible to bring the dumbbell down too low. This puts your shoulders in an unsafe position.
You don’t have to stop as soon as your arms are parallel to the ground, but you shouldn’t go all the way to end range unless you have the strength and shoulder mobility to do so correctly.
4. Not Keeping Your Upper Body Tight
It’s easy to think that you don’t have to follow the same cues for a barbell bench press when you’re lifting with dumbbells, especially if the weight is light in comparison.
But maintaining tension in your upper body is especially important when doing one arm chest presses because it helps keep your body stable and prevents your torso from twisting on the bench.
Who Should Do the Single-Arm Dumbbell Bench Press?
You should do the single-arm dumbbell bench press if you:
- Want to increase bench press strength
- Have significant strength imbalances between your right and left arms
- Are looking for different ways to add more pressing volume into your routine
- Want to improve your shoulder stability
- Are rehabbing an injury and need to bring your pressing strength back up
How to Program the Single-Arm Dumbbell Bench Press
Whether you’re a powerlifter or someone who strength trains recreationally, I recommend programming the single-arm dumbbell bench press as an accessory movement towards the end of an upper body day. It’s not a movement with which you’d try to find a 1RM.
Doing 3 sets of 10-12 reps with a weight that you can manage for 15 reps is a good starting point. This will allow you to continue progressing each week by either increasing the weight or increasing total volume through additional reps or sets.
If you’d prefer to use it more as a strength-building movement, you can move it closer to the beginning of your workout (but still after your main bench press sets) and start with 3-4 sets of 6-8 reps.
I’d also suggest doing this movement before any direct ab work to avoid fatiguing your core too much and affecting your balance and stability.
Other Upper Body Exercise Guides:
- Negative Bench Press: What Is It, How-To, Benefits, Mistakes
- Diamond Push Up: How To, Benefits, Muscles Worked
Frequently Asked Questions
Is the One-Arm Dumbbell Bench Press Effective?
The one-arm dumbbell bench press is effective at improving strength asymmetries, rehabbing injuries or preventing new ones from occurring and increasing shoulder stability. It’s also more effective than regular dumbbell bench presses at working your core due to the extra stabilization that’s required.
Is the Single-Arm Dumbbell Bench Press Harder?
The single-arm dumbbell bench press is harder because the offset loading demands more core and upper body stability. There’s also no way for your stronger side to provide assistance in the areas where your non-dominant arm is lacking.
Other Dumbbell Articles:
Final Thoughts
The single-arm dumbbell bench press is one of my favorite exercises for addressing strength imbalances between my right and left arms. It also has several other benefits including improved core and shoulder stability, a greater range of motion than barbell bench presses, and injury prevention.
The single-arm dumbbell bench press is best done as an accessory movement after you’ve done your main bench press sets. You should start with a weight that’s light enough for you to complete about 15 reps and leave some reps in reserve so you can consistently improve the amount of weight you’re lifting or your total volume over time.
About The Author
Javad Bakhshinejad was born and raised in the Washington Area. Currently, he is a student at Seattle University where he’s been pursuing an MS in Kinesiology, and has been a Strength Coach in the athletic department. He was a competitive bodybuilder for 8 years where he later transitioned to competitive powerlifting for 4 years. Currently, He has his own personal coaching business, where he works with powerlifters and bodybuilders.
