This is actually an extremely common problem, “Why Are My Biceps Tall But Not Wide?”
In fact, I know that many trainees are extremely satisfied with the peak of their biceps.
Plus, their arms literally look massive from the side.
However, a quick face-on view and your biceps, and arms in general, look extremely skinny, and devoid of any width.
So, I’d like to explain the possible reasons why your biceps lack width and what you can do to fix this.
Why Are My Biceps Tall But Not Wide?
One of the main reasons that your biceps are tall but not wide is that your biceps training is uneven. Many trainees focus on working the short head of the biceps by performing exercises with supination (palms facing up, thumbs pointing out). However, this can typically leave the long head of the bicep lagging behind. Furthermore, training the brachialis can actually make the biceps both taller and wider.
1. Your Biceps Training is Uneven
The most obvious reason for your biceps being tall but not wide comes down to how you train your biceps.
In fact, the vast majority of people don’t train their biceps evenly.
There appears to be a huge focus on training the short head of the bicep, which I guess is what you’d call the “show muscle”.
Training the short head usually involves performing biceps exercises with supination.
In other words, your palms are facing up, while your thumbs are pointing out to the side.
This is the position you’ll generally take up when performing barbell bicep curls, alternating dumbbell curls, concentration curls, preacher curls, etc.
In fact, I can guarantee that for some of you these 4 exercises may constitute your entire bicep training.
However, as the same suggests, biceps is plural.
So, you should actually be training both heads, i.e. the long head and short head.
Furthermore, there is more to your biceps training than the main two heads, and I’ll cover this in a moment.
The short head is the bicep muscle on the inside of the upper arm, whereas the long head is on the outside.
Plus, there is a tendency for the long head to not be as well-developed as the short head in most individuals.
I guess this once more comes down uneven biceps training.
You’ll want to train your biceps with supination, and pronation (palms facing down, thumbs pointing in), as well as exercises with the thumbs pointing towards each other.
A Great Exercise for the Long Head of the Bicep
If you feel your biceps long head is falling behind the short head then one of the best exercises to perform are seated incline dumbbell curls.
The tension placed on the biceps is actually fairly limited during the bottom two-thirds of incline curls.
However, this also provides a fantastic stretch of the bicep muscle at the bottom of the movement, something which you may not be used to with your current bicep training.
With that being said, the biceps are extremely active for the final one-third of incline curls.
In fact, so much so, that this is one of those exercises where you’ll really feel the “burn”.
So, if you’re not already doing them, incorporate seated incline dumbbell bicep curls into your routine.
2. Focus More on Training the Brachialis
I mentioned a moment ago that there’s more to training the biceps rather than just focusing on the long and short heads.
I am specifically talking about the brachialis
The brachialis lies directly below the long head and unfortunately it’s also a muscle that is not known that well or trained that regularly.
However, the brachialis is somewhat responsible for bicep width, plus it pushes up the biceps.
So, in effect, you could say that training the brachialis is responsible for making your biceps both taller and wider.
The brachialis has one sole purpose in the human body, and that is to flex your arm.
With that being said, training the brachialis can make a huge difference to how your biceps look.
The best way to train the brachialis is with either a pronated or neutral grip.
But, if much of your biceps training focuses on supination then you’ll want to train the brachialis with a neutral grip.
Probably the best exercise to achieve this is hammer curls.
However, a study conducted by the American College of Sports Medicine found that you can actually increase brachialis involvement by performing a really slow eccentric phase.
Basically, hammer curls will always work both the biceps and brachialis.
But, when you slow down the eccentric portion of the movement you’ll decrease bicep involvement, while increasing brachialis involvement.
So, a great way to perform your hammer curls will be to use a 5-second eccentric phase.
Therefore, curl the weight up as normal, and then spend 5 seconds slowly lowering the dumbbells back to your sides.
Brachialis Exercises For Wider & Thicker Biceps
3. Genetics Plays a Role in Bicep Width
There’s no two ways about it, genetics will play a role in bicep width.
Now, don’t get me wrong, you can definitely increase the size of your biceps through training.
Plus, you can improve the definition of your biceps through nutrition.
However, your genetics will always limit what you are capable of achieving.
In fact, there are the lucky ones who can perform a few bicep exercises mixed with pulling movements and achieve both tall and wide biceps.
Then again, there are those of us who seem to target the biceps with amazing regularity, and are unable to produce the same results as those who train less than us.
Unfortunately, this is typically down to a difference in genetics.
Some of us will always have skinny arms, especially in terms of width, regardless of how we train and eat.
Obviously, that’s not to say that you shouldn’t focus on training biceps, while perhaps focusing on width.
You can still make changes, but they perhaps won’t be as dramatic as you hoped.
So, it makes sense to continue training both bicep heads, the brachialis, and the brachioradialis.
Just in case you weren’t aware, the brachioradialis is the forearm muscle that flexes the forearm at the elbow.
You will actually hit the brachioradialis with hammer curls too, although most exercises performed with a pronated grip will do a great job, e.g. reverse curls.
Further “Biceps” Reading
4. Don’t Forget Your Triceps
Pure and simple, if you want big arms then you have to train your triceps.
In fact, I would suggest that you spend more time (reps and sets) on training your triceps than biceps.
The biceps are typically one of the most trained muscle groups in the gym environment.
I guess this comes down to your biceps being “on show” much of the time.
Basically, you can see your biceps in the mirror, plus you can see them whenever you look down.
But, the same cannot be said for the triceps (they’re behind you) and they are often forgotten about, and definitely don’t receive as much attention as the biceps.
The triceps actually take up approximately two-thirds of the upper arm.
Furthermore, the triceps have three heads compared to the two heads of the biceps.
So, the triceps are definitely the bigger upper arm muscle.
Realistically, should this not mean that you need to train the triceps more than the biceps?
If you want your arms to look massive then surely the bigger of the arm muscles deserves more of your attention.
And yet, this is rarely the case.
I will also say that more focus on your triceps will help to give you that wider arm look than avoiding tricep training altogether.
So, as you can see, there are a few reasons why your biceps are tall but not wide.
This mainly comes down to uneven training of your biceps.
Realistically, you should be training the short head, long head, brachialis, and brachioradialis.
However, in truth, most bicep training seems to specifically focus on the short head.
A couple of great exercises to help with bicep width include seated incline dumbbell bicep curls and hammer curls.
Furthermore, if you perform an extremely slow eccentric with hammer curls you’ll target the brachialis to much greater effect.
And it is this that helps to increase the width of your biceps.
Hi, I’m Partha, owner and founder of My Bodyweight Exercises. I am a Level 3 Personal Trainer and Certified Strength & Conditioning Specialist through the Register of Exercise Professionals, United Kingdom. I have been a regular gym-goer since 2000 and coaching clients since 2012. My aim is to help you achieve your body composition goals.