When it comes to building bigger arms everyone thinks of the biceps and triceps first. But the brachialis is the true unsung hero that is often neglected. This is why, for optimal arm development, it is crucial to incorporate some isolation exercises for the brachialis into your workout program.
This small yet powerful muscle is located between the biceps and triceps, and is responsible for flexing the elbow.
In this article, we’ll take a closer look at the brachialis muscle, its importance in arm size and strength, and the five most effective exercises for the brachialis.
By incorporating these brachialis exercises into your workout routine, you’ll be on your way to building the impressive arms you’ve always wanted.
So, let’s dive in.
Anatomy of the Brachialis Muscle
The brachialis muscle is a muscle located in the upper arm. It’s positioned beneath the biceps and sits on the lower front part of the humerus bone.
It’s primary function is elbow flexion – think of curling exercises.
While the brachialis is about twice as smaller than the biceps it is a much stronger elbow flexer (source).
This is because the brachialis does not cross the shoulder joint and acts as a “pure flexor” of the forearm and elbow (source). In other words, it can concentrate solely on elbow movement.
Even though the biceps is the most noticeable muscle in the upper arm, its main function is to assist and stabilize the deeper and stronger brachialis muscle when lifting or lowering the forearm (source).
Yes, you read that right. The biceps is not the only star of the show during curling exercises. As a matter of fact, the biceps is more of a backstage assistant.
I’m going to go into more detail in the following sections of the article, it will all make sense.
What Are The Benefits Of Exercising The Brachialis?
Even though, when compared to the triceps and biceps, the brachialis is a much smaller muscle, it still makes up 20% of the total muscle mass of your arms (source). So, by exercising the muscle you’re ultimately contributing to your overall arm size.
But what makes the brachialis such a unique muscle is the way it interacts with its neighbours – the biceps and triceps.
Because of its location, when the brachialis grows in size it also pushes out the biceps and triceps, giving your arms an even larger appearance. A double whammy, if you will. This may also lead to wider and thicker looking arms.
As a powerful elbow flexor, training the brachialis will have a trickled-down effect. What that means is that brachialis exercises will also improve your strength during other curling/pulling exercises.
This is especially important if your goal is to improve functional strength.
Lastly, The elbow joint is a vulnerable area that is prone to injury due to the complexity of the joints within the elbow and the presence of numerous muscles, tendons, and ligaments that hold it together. Additionally, the elbow is the first joint that experiences the force generated by lifting weights, making it susceptible to damage.
Increasing the strength of your brachialis can significantly reduce the risk of injury.
How to Train and Work The Brachialis
I don’t want to just give you a list of exercises for the brachialis and call it a day. I want you to understand why they work at targeting the brachialis.
This will also help ensure that you maintain proper form and range of motion (ROM) during these movements.
There are two main strategies that will allow us to isolate the brachialis:
- Grip position; and
- Eccentric movement
Grip Position
There are three main muscles that act on elbow flexion:
- Brachialis
- Brachioradialis
- Biceps
In order to isolate the brachialis, we would need to place the remaining two muscles in a mechanical disadvantage.
The Biceps
The bicep is tri-articulate – it acts on three joints to perform three different functions (source, source).
The three joints are:
- Elbow – to perform elbow flexion.
- Shoulder joint – the bring the arm upward, in a forward motion.
- Radio-ulnar joint – supination of the forearm.
Here’s another shocking revelation:
If you are not adding some form of supination (palm pointing up with pinkie rotating out) to your curling exercises, you’re targeting the brachialis far more than the biceps. As we discussed, this is because the brachialis is a much stronger elbow flexor than the biceps.
When supination is combined with flexion, the mechanical momentum of the brachialis is disadvantaged, and the biceps takes over (source).
In order to isolate the brachialis all we have to do is the opposite. Keep the arm in a neutral (palm pointing in) or pronated (palm pointing down) position.
The Brachioradialis
There appears to be nothing we can do to remove the brachioradialis from the equation.
This is the muscle located on the lateral (outer) side of the forearm. It is involved in stabilizing the elbow joint.
According to research papers, the brachioradialis appears to be active both during neutral and pronated grips (source, source).
According to the same research, the brachioradialis seems to compensate the biceps when the palms in in pronation.
Slow Eccentric Movement
Eccentric movement is a lenghtening muscle contraction. For example, when lowering the barbell during barbell curls.
This paper from the American College of Sports and Medicine reported that by slowing down the eccentric portion of a curling exercise you decrease the involvement of the biceps and increase that of the brachialis.
According to the researchers, this is due to the structure and fibre type differences between the two muscle groups.
The brachialis is likely to be more slow-twitch muscle fibres.
The 5 Most Effective Exercises for The Brachialis
1. Hammer Curls
The hammer curl is the probably one of the most well-known exercises for the brachialis.
Because you’re using a neutral grip and are keeping your arms close to the body, you’re allowing the brachialis to take over.
How to perform
- Stand up straight with your feet shoulder-width apart and your arms extended down by your sides, holding a pair of dumbbells with your palms facing your body.
- Curl the weights up towards your shoulders while keeping your elbows close to your sides and your palms facing each other.
- Slowly lower the weights back down to the starting position and repeat for the desired number of reps.
2. Zottman Curls
Zottman curls will target all of the elbow flexors – biceps, brachialis, and brachioradialis.
It can be a great addition to your arm workout as it allows you to also save some time.
How to perform
- Stand up straight with your feet shoulder-width apart and your arms extended down by your sides, holding a pair of dumbbells with your palms facing your body.
- Curl the weights up towards your shoulders while keeping your elbows close to your sides and your palms facing up.
- At the top of the curl, rotate your wrists so that your palms are now facing down.
- Slowly lower the weights back down to the starting position and repeat for the desired number of reps.
3. Rope Hammer Curls
The main difference between traditional hammer curls and the rope hammer curls is time under tension.
A cable machine will apply more time under tension, especially during the upper portion of the exercise.
How to perform
- Stand with your feet shoulder-width apart and hold a rope attached to a cable machine with an underhand grip.
- Keep your elbows close to your sides and curl the rope towards your shoulders while exhaling.
- Pause at the top of the movement and squeeze your biceps and brachialis.
- Slowly lower the rope back to the starting position while inhaling.
- Repeat for the desired number of repetitions.
4. E-Z Reverse Curls
Using an overhand (pronated) grip will allow you to target the brachialis.
The E-Z bar releaves some of the strain that you place on your wrists and takes away some of the involvement of the brachioradialis.
How to perform
- Stand with your feet shoulder-width apart and hold an E-Z bar with an overhand grip (palms facing down).
- Keep your elbows close to your sides and curl the bar towards your shoulders while exhaling.
- Pause at the top of the movement and squeeze your biceps and brachialis.
- Slowly lower the bar back to the starting position while inhaling.
- Repeat for the desired number of repetitions.
5. Cross Body Hammer Curls
According to experts, while the hammer curl is great for targetting the brachialis, it also involves the brachioradialis far too much.
While the cross body hammer curls place more strain on the brachialis directly.
How to perform
- Stand straight with your feet shoulder-width apart and hold a dumbbell in each hand with palms facing inwards towards your body.
- Extend your arms down by your sides, fully extending your elbows.
- Begin the exercise by curling the right arm dumbbell up towards your opposite shoulder in a diagonal motion.
- As you curl the dumbbell, keep your elbow close to your body and rotate your wrist so that your palm faces your shoulder.
- Hold the contraction for a second at the top of the curl, and then lower the dumbbell back down to the starting position.
- Repeat the same motion on the opposite side, curling the left arm dumbbell up towards your right shoulder.
- Alternate arms for the desired number of repetitions.
Remember to use a weight that challenges you but allows you to maintain good form throughout the exercise. It’s better to use a lighter weight and focus on proper form than to use a heavier weight and risk injury.
Brachialis Exercises to avoid
I’ve seen a few articles list some exercises as suitable for the brachialis, but that’s not the case.
For example, exercises that ask of you to extent your arms in front of the body will engage the biceps.
The long head of the bicep is also responsible for shoulder flexion – bringing the arm forward, in front of the body. This is true for the initial 30° of elevation (source).
Exercises such as preacher curls and incline dumbbell curls will involve the biceps more than exercises where you keep arms to your side. This is because they bring your arms infront of the body at a 30-45 degree angle, enough to engage the biceps.
I have also seen exercises such as pull-ups and neutral grip chin-ups make their way in some lists of exercises for the brachialis. While these exercises will engage the brachialis, they are back exercises.
And as such your goal should be to make the mental effort to minimize arm involvement and focus on engaging your back muscles.
Conclusion
Building bigger and stronger arms goes beyond focusing solely on the biceps and triceps, it’s important not to forget about the brachialis.
Incorporating some isolation exercises for the brachialis into your workout routine will help in achieving optimal arm development. By exercising the brachialis, you are contributing to your overall arm size, and you also improve your strength during other curling/pulling exercises. Moreover, exercising the brachialis can significantly reduce the risk of injury.
The article provides information about the anatomy of the brachialis muscle, the benefits of exercising it, and the five most effective exercises for the brachialis. Understanding the strategies that isolate the brachialis, including grip position and slow eccentric movement, can help ensure that proper form and range of motion is maintained during these movements.
