Get to Know the Brachioradialis - The Muscle That Flexes Your Arm

[BigArvin]

Do you see a bulging muscle when you flex your forearm and plan to grow it? Many people are confused by the appearance of a bulging muscle on their arm during fitness and strength training. The brachioradialis muscle is a long, spindle-shaped muscle that flexes the forearm at the elbow.

The brachioradialis muscle is involved in many everyday activities, such as lifting objects, carrying groceries, and using tools. It is also crucial for sports that require forearm flexion, such as baseball, tennis, and golf.

Anatomy of the Brachioradialis Muscle​

The brachioradialis muscle is a long, spindle-shaped muscle located on the lateral side of the forearm. It is the most superficial muscle in this region, which you can easily palpate when flexing and semi-pronating the forearm. The brachioradialis muscle forms the lateral border of the cubital fossa or elbow pit.

The muscle attaches to the styloid process of the radius, which is a thin, bony projection situated at the end of the forearm's radius bone. It is located on the outer or lateral side of the wrist, just above the thumb.

The muscle belly of the brachioradialis is the thick, fleshy part of the muscle. It runs down the forearm, extending from its origin near the elbow to its insertion point on the ulna. The muscle belly gives the brachioradialis its distinct shape and size, contributing to the muscular appearance of the lateral forearm.

The tendon of the brachioradialis muscle passes through the extensor retinaculum, a fibrous band that crosses the wrist joint and inserts onto the styloid process of the radius.

Function​

Elbow Flexion​

Elbow flexion is the primary role of the brachioradialis. This muscle comes into play when you bend your elbow, like lifting a glass of water or performing a bicep curl. It flexes the forearm at the elbow joint, allowing for various everyday movements.

Forearm Pronation​

The brachioradialis muscle contributes to forearm pronation when the arm is fully supinated. This movement involves rotating the forearm so that the palm faces downward. Such a motion is invaluable in various activities, including opening doorknobs, turning screwdrivers, or using hand tools.

Conversely, when the arm is fully pronated, the brachioradialis lends its strength to facilitate forearm supination. It entails turning the forearm so that the palm faces upward or forward. This action is beneficial in tasks like pouring liquid from a container or holding objects with a stable grip.

Eccentric Contraction When Lowering Weights​

During the eccentric contraction phase in weightlifting, this muscle plays a crucial role in controlling the movement. Eccentric contraction occurs when the muscle lengthens during contraction.

Eccentric contractions are also crucial for muscle growth and strength development. Studies have shown that eccentric training can increase muscle size and strength more than concentric training alone. One example of an eccentric contraction is the lowering phase of a biceps curl. When you lower the weight, the biceps muscle is lengthening under tension.

Concentric Contraction When Lifting Weights​

When you lift weights, especially during exercises like bicep curls, hammer curls, or reverse curls, the brachioradialis also comes into play. It performs concentric contractions as you lift the weight, whether a dumbbell or barbell, when the muscle fibers actively shorten, creating tension. While the biceps may get much attention, the brachioradialis contributes significantly to the effort.

The concentric contraction of the brachioradialis generates the force necessary to lift the weight against gravity. But this muscle also provides more than raw power. It also plays a crucial role in controlling the movement. This control is essential for maintaining proper form and preventing injury during weightlifting exercises.

Exercises Targeting the Brachioradialis​

Bicep Curls with Palms Up​

This exercise emphasizes the brachioradialis and biceps brachii, creating a balanced arm workout. Hold a dumbbell in each hand with your palms facing upward. Keep your elbows close to your body and curl the weights toward your shoulders, focusing on flexing your forearms.

Bicep curls with palms up can help increase the brachioradialis muscle's strength and size. It benefits athletes who need a strong forearm and wrist, such as baseball players, tennis players, and golfers.

Reverse Bicep Curls​

Reverse bicep curls specifically target the brachioradialis, helping to enhance its size and strength than traditional bicep curls because they use a pronated grip. Grip a dumbbell in each hand with your palms facing downward. Maintain a slight bend in your elbows and lift the weights by flexing your forearms.

It benefits athletes who need a strong forearm and wrist, such as baseball players, tennis players, and golfers. People who want to improve their appearance and have more muscular forearms can also benefit from the reverse bicep curls exercise.

Hammer Curls​

Hammer curls can help increase the brachioradialis muscle's strength and size. A strong brachioradialis muscle can help improve athletic performance in various sports. It can also help reduce forearm pain in people with tendinitis and tennis elbow conditions. This exercise works the brachioradialis from a different angle, promoting well-rounded forearm development.

Hold a dumbbell in each hand with your palms facing each other (neutral grip). Curl the weights toward your shoulders, emphasizing the flexion of the forearms.

Resistance Band Exercises​

Resistance bands are incredibly versatile and portable, making them a convenient choice for home workouts or on the go. You can perform a wide range of brachioradialis-targeted exercises with a single band. These bands enable you to mimic functional movements, such as gripping and twisting, closely resembling real-world activities. It helps build functional strength that you can apply to everyday tasks.

You can use the resistance band whether you are standing or seated. Hold the band with an underhand grip, and perform curls while keeping your upper arms stationary. Squeeze your brachioradialis at the top of the movement.

Importance of the Brachioradialis​

The brachioradialis is a vital stabilizer of the forearm and elbow. It helps maintain these joints' stability during gripping, lifting, and carrying activities. With proper strength, these everyday tasks would be more manageable. It is a vital part of injury prevention from muscle overuse that could lead to rupture, tendonitis, strain, and discomfort.

The brachioradialis adds significant visual appeal to the arms. It contributes to the overall arm definition and complements the appearance of the biceps and triceps. A well-developed brachioradialis creates a balanced and sculpted look, enhancing the aesthetics of your arms.

Miscellaneous​

Synergists: Brachialis and Biceps Brachii​

The brachioradialis rarely works alone. It synergistically teams up with two prominent arm muscles: the brachialis and the biceps brachii. The brachialis lies beneath the biceps brachii and plays a significant role in elbow flexion. When you bend your elbow, especially while lifting weights or carrying objects, the brachialis joins forces with the brachioradialis to provide strength and stability.

The biceps brachii is a well-known muscle for elbow flexion and forearm supination. It works closely with the brachioradialis and brachialis during exercises like curls.

Caution: Overuse and Tendinopathy​

While strengthening the brachioradialis is essential, it's vital to exercise caution. Overuse in activities that involve repetitive forearm movements can lead to tendinopathy or inflammation of the tendons. To prevent this, ensure your workout routine includes proper warm-up, stretching, and adequate rest between sessions.

EMG Activity Levels During Exercise​

Understanding the electromyography (EMG) activity levels during exercises can help you optimize your brachioradialis workout. EMG measures the electrical activity in muscles and provides insights into which exercises activate the brachioradialis most effectively. Exercises like hammer and reverse curls elicit high EMG activity in this muscle.

Brachioradialis Reflex​

The brachioradialis reflex is a deep tendon reflex used to assess the function of the radial nerve. This reflex tests the integrity of the radial nerve and the C5-C6 spinal cord segments.

A patient extends his arm at the elbow with the forearm pronated to perform the brachioradialis reflex. The examiner then taps the tendon of the brachioradialis muscle with a reflex hammer. It should cause a contraction of the brachioradialis muscle and flexion of the elbow joint.

A brisk and normal reflex response indicates the proper functioning of these neural pathways. Conversely, a decreased or absent brachioradialis reflex may indicate a problem with the radial nerve or the spinal cord.

Conclusion​

The brachioradialis muscle, responsible for the bulging appearance on the side of your arm, is vital for arm flexion and stability. Its collaboration with the biceps brachii and brachialis muscles allows for seamless forearm flexion, making everyday activities a breeze. Incorporating exercises like bicep curls with palms up, reverse bicep curls, hammer curls, and resistance band exercises into your workout routine can help you achieve balanced and impressive arm strength.

Taking care of the brachioradialis muscle is essential to prevent injuries and maintain optimal function. If you experience pain in the forearm or elbow, see a doctor or physical therapist to get a diagnosis and treatment plan.

Frequently Asked Questions​

How can I isolate the brachioradialis during training?

You can focus on exercises that use a neutral or pronated grip to isolate the brachioradialis during training. It is because the brachioradialis is more active in these positions. You can do hammer curls, reverse bicep curls, and resistance band exercises to isolate the brachioradialis.

How can I improve brachioradialis strength and hypertrophy?

To enhance brachioradialis strength and size, incorporate exercises like hammer curls, reverse curls, and neutral grip bicep curls into your routine. Focus on maintaining proper form, progressively increasing weights, and training 2-3 times weekly with adequate rest. A balanced diet, hydration, and consistency are essential for optimal results in building brachioradialis muscle strength and hypertrophy.

How do I know if I have a strained brachioradialis?

Identifying a strained brachioradialis involves recognizing symptoms such as localized pain or tenderness in the forearm, particularly near the elbow. You may experience discomfort when bending your elbow or gripping objects. Swelling and bruising can also occur.