The bicep is one of the most visible and identifiable muscles in the human body, and for a good reason. It is a large muscle that helps you lift things, gives your arm definition and shape, and makes it easier to push against objects.
But what if one bicep is bigger than the other? What does this mean? And should you be worried about it?
The definition of a bicep is quite simple. Yet, this body part is the most prominent muscle of the upper arm, giving support whenever lifting or lowering the forearm. The truth is each side of your body will never be the same size.
For example, your right bicep may be stronger than the left. You see this a lot when people are lifting, carrying heavy loads, or opening the door. When one bicep is stronger than the other, there will be a significant difference in size.
According to Scientific American, 70 to 95 percent of the world population is right-handed. Yes, that means that only 10 to 30 percent are left-handed. Most people have a “dominant” arm that they use in day-to-day activities.
For some people, their dominant arm can be as much as 1-inch bigger or more. This is harmless unless it causes muscle strain or limits range of motion during exercises. However, that’s not to say you should not fix the issue.
In this article, we explain why you have one bicep bigger than the other but, more importantly, how to fix it.
Can One Bicep Be Bigger Than the Other?
This is a common question, and the answer is yes – one bicep can be bigger than the other. This can happen due to a number of factors, such as muscle imbalance or weaker arm.
We all have a dominant hand that prefers to do almost everything when doing specific tasks, for example:
- Brushing your teeth
- Eating meals
- Carrying shopping bags
The list is endless. If you think about your daily activities, you will notice you have a preference. The use of repetition over time leads to a slightly more developed arm.
The bicep may be slightly different in size, and this is where an imbalance can be the result of training one part of the body than the other.
What Causes One Bicep to Be Slightly Bigger?
The main cause of one arm being bigger than the other is not necessarily because you use one arm more frequently for day-to-day tasks. Combing your hair with just your right hand will not suddenly make the bicep on your arm bigger. There are some other factors at play.
1. Muscle Dominance
One of the most common reasons for one bicep being bigger than the other is muscle dominance. Muscle dominance means that you most likely have a dominant hand/arm. Most people do, unless you are in the rare minority of ambidextrous individuals. For example, when lifting equipment, one arm will do most of the lifting.
This is not even something you control because it is almost an involuntary action resulting from muscle memory. Having an overly dominant hand can be one of the main reasons why one bicep is bigger.
2. Muscle Fiber Proportions
Another reason for one bicep being bigger than the other can be due to muscle fiber proportions. Your muscle fiber proportions might be slightly different between your two arms. This means that the higher proportion of fibers in one arm can, over time, result in more muscle growth as these muscle fibers are more responsive to growth.
This occurs when one muscle has a higher percentage of slow-twitch muscle fibers and the other has a higher percentage of fast-twitch muscle fibers. The fast-twitch muscle fibers are bigger and stronger than the slow-twitch muscle fibers, resulting in one bicep being bigger than the other.
Some people might be better with their dominant hands. These muscle movements will result in bigger biceps. The arm that receives more stimulation grows bigger. The margins for this are small, but it can still be a factor.
Genetics can also play a role in one bicep being bigger than the other. This occurs when one muscle is genetically predisposed to be bigger than the other.
The human body is not symmetrical. While most bodybuilders aim to develop a truly symmetrical physique, only top-level athletes make it to this position because of genetics.
Take, for example; your abs could be asymmetrical. The right side of your abs is positioned higher up than the left side, and this will not change through weight-lifting as it is a genetic factor. Muscle bellies and the shape of a muscle can also dictate its size.
Your muscle imbalance could therefore be genetic, and workouts can help reduce the imbalance. This is not something you can always achieve, as you cannot shape a muscle.
However, here is how you can fix it based on shape.
What Can I Do If One Bicep Is Bigger Than the Other?
Fixing a muscle imbalance is not necessarily easy. However, it is very achievable if you follow these basic steps listed below.
1. Use Unilateral Exercises
The best thing to reduce and fix a muscle imbalance in your arms is through unilateral workouts. This means that each arm will work independently from the other one. Take the barbell bench press, for example.
With a fixed bar, it can be easy for a dominant arm to take over and essentially lift more of the weight. If, however, you use a barbell with dumbbells, both arms will now be equally responsible for lifting the exact same amount of weight.
The most dominant arm can no longer help the non-dominant arm. Therefore, all reps and sets will create equal stimulation between both arms. This can be done through multiple workouts for the shoulders and arms.
We only caution that in some workouts, it is perfectly fine to use the Leadnovo Dumbbell and barbell set to balance the training stimulation and reduce muscle imbalances.
Unilateral workouts are the most beneficial way to reduce muscle imbalance; this should be the first thing you start to implement.
2. Consistent Workout Reps
In addition to unilateral exercises, it is important to do consistent reps and sets when training your biceps. This will help to increase the size of both arms.
Consistent workout reps are usually more of a preventative measure. However, it is something common with younger lifters not necessarily following a set rep scheme, and that is an imbalance in terms of reps.
Let us say you are doing dumbbell curls, and your rep target is 10 reps with each arm. Your dominant arm is likely going to hit this target comfortably, depending on your weight selection.
Lifters will push each arm on a set even though the points for both arms could be different. If you can only hit 7 reps with your left arm but manage to do 12 with your right, there is a very good chance that your right arm will only be bigger.
Make sure you use the same number of reps for each arm. Over time, this will allow the smaller arm to catch up in strength and size to the larger one.
3. Increased Training Frequency
A third way to fix one bicep being bigger than the other is through increased training frequency.
If you are following the first two steps mentioned above, then this third point should only be considered as a last resort in examples of extreme muscle imbalances. Increasing training frequency involves working the non-dominant arm with a higher frequency than the dominant arm.
We suggest Ativafit Resistance Bike for arms.
This is the approach many people try to fix a muscle imbalance. You should increase the workout frequency for your non-dominant arm. This could be as simple as adding an extra 5 sets to each workout.
The reason why this is a better approach is that the stimulation will activate muscle protein synthesis (MPS). This is a muscle-building state brought about by both resistance training and protein consumption that can last anywhere from 24-72 hours, depending on how intense your workouts are.
By activating a bicep with some additional, you can activate more muscle growth without impacting your central nervous system through additional training sessions.
What Workouts Can I Do to Make Both Biceps Symmetrical?
There are a lot of ways you can train your biceps. Some people like to put their focus on one side at a time, while others prefer to train both sides simultaneously. Whatever your preference, there are certain exercises that can help you achieve symmetry in your biceps.
1. Alternative Curls
How to perform alternative curls
- Hold the right dumbbell in both hands.
- Raise the elbow on your weaker arm up to your chest.
- Lower the dumbbell down.
- Repeat the same workout on the other arm.
Here’s a detailed YouTube video on how to do alternative curls.
2. Hammer Curls
This workout is similar to traditional curls.
- Keep both palms facing each other.
- Lift the dumbbell to your chest and feel the tension.
- Keep both elbows pinned to your body
- Use your arms to move the dumbbell.
For more, check out this Youtube Video.
3. Dumbbell Shoulder Press
- Position a bench at a 90-degree angle.
- Lay with your back against the bench while carrying two dumbbells over your shoulders.
- Extend both arms to push the dumbbell above your head.
- Maintain momentum and return to the starting position.
- You can also do this workout one arm at a time with breaks in between reps.
Video: How to do a dumbbell shoulder press.
Some exercises you can do at home without equipment to make both arms even stronger are:
- Tricep dips
- Wall sits
- Bicep curls with cans of food or weights
If you are looking to specifically target the weaker arm, there are exercises that can help. For example, if your left arm is weaker than your right, you can do more repetitions with your left arm during workouts.
The importance of doing exercises that target all parts of the bicep muscle group is key to getting an even muscular development. The biceps muscle group comprises the brachialis muscle, which is found underneath the biceps, and the bicep brachii, which is located on top of the forearm. These two muscles make up what we call biceps.
For each arm joint (elbow joint and shoulder joint), there is a weaker and stronger muscle. If one bicep is bigger than the other, the weaker muscle is likely the biceps brachii, and the stronger muscle is the brachialis.
Frequently Asked Questions
Is it bad if one arm is bigger than the other?
If it is only slightly bigger, then it is not a bad thing. There will almost always be imbalances in your body. Take, for instance, a lot of people have one arm longer than the other. However, you do not want to see too much difference in arm size, as this can affect posture and other muscle groups. This is why we suggest you use the DEDAYL hydraulic power twister.
Do muscle imbalances fix themselves?
No. Muscle imbalances usually occur through our everyday movements and posture. If left unattended, they are more likely to get worse rather than fix themselves.
Why is my right side bigger than my left side?
There are several reasons why one arm can be bigger than the other. As mentioned above, muscle dominance, muscle fiber proportions, and genetics can all play a role.
Is it normal to have uneven arm size?
While it is not considered normal to have one arm that is significantly bigger than the other, it is not necessarily a cause for alarm. Several things can cause one arm to be larger than the other, such as muscle imbalance, genetic disposition, or injury. However, if you are concerned about the size discrepancy, you can speak to a doctor.
Professional bodybuilders who try to be extremely symmetrical too have differences in their left and right side of arms. Many sportspersons like tennis players, badminton players, and cyclists have strong-sided body parts because they are either left-handed or right-handed.
No matter how much they train to keep them balanced, the difference will always show.
So, having a bigger bicep is okay.
However, one should always add some unilateral isolation workouts to the weak bicep if they feel there is too much difference between the biceps.
Training should not be all doing challenging core exercises and cardio. You can train your abs with this modern ab wheel kit when trying to be symmetrical.
There are a few ways you can train your biceps to increase symmetry. One of the most effective is to perform alternating curls. The alternating curl, or alternating lateral raise, is a great way to train both biceps simultaneously. Simply perform one set of each exercise with both arms and switch back between the two sets in the following weeks. This will help increase muscle balance and symmetrical development.
Another way to train your right and left biceps is to use a resistance band to create a slow, constant tension that forces your muscles to work equally as hard. This will help prevent one arm from having an advantage over the other.
Finally, you can use heavier weights on one arm when doing curls or tricep extensions, which will help keep the two muscles aligned as you build strength and size.