Hammer Curls vs. Bicep Curls: Benefits for Arm Thickness, Forearms, and Grip Strength

Why are hammer curls better than bicep curls?

While neither exercise is inherently "better" than the other, hammer curls offer distinct advantages by targeting different muscles for overall arm thickness, forearm development, and grip strength, making them a crucial complement to the bicep curl for comprehensive arm development and often a more comfortable option for individuals experiencing bicep tendon discomfort.

Introduction to Arm Flexor Training

The quest for stronger, more muscular arms often revolves around exercises like the bicep curl. However, to truly maximize arm development and function, it's essential to understand the nuanced biomechanics and muscle activation patterns of various curling movements. The question of whether hammer curls are "better" than traditional bicep curls prompts a deeper dive into the specific muscles each exercise emphasizes and the unique benefits they offer.

Understanding the Standard Bicep Curl

The standard bicep curl, performed with a supinated grip (palms facing upwards), is a foundational exercise for targeting the biceps brachii.

• Primary Muscles Targeted: The Biceps Brachii (comprising a long head and a short head) is the star of this movement. Its primary functions are elbow flexion and forearm supination (rotating the palm upwards).
• Grip: The supinated grip maximizes the leverage of the biceps brachii, particularly its supination function, making it highly effective for developing the peak and overall mass of this muscle.
• Biomechanical Advantage: This grip places the biceps in its strongest position to contract, leading to significant activation and hypertrophy of the biceps brachii itself.

Deconstructing the Hammer Curl

The hammer curl, characterized by a neutral grip (palms facing each other, like holding a hammer), fundamentally alters the muscle activation profile compared to a standard bicep curl.

• Primary Muscles Targeted: While the biceps brachii still contributes to elbow flexion, the neutral grip shifts significant emphasis to two other crucial arm flexors:
  • The Brachialis: This muscle lies underneath the biceps brachii and is a pure elbow flexor, unaffected by forearm rotation. Developing the brachialis pushes the biceps up, contributing significantly to overall arm thickness.
  • The Brachioradialis: Located in the forearm, this muscle is most active during elbow flexion with a neutral grip. It plays a key role in forearm size and strength.
• Grip: The neutral grip effectively minimizes the biceps' role in supination, allowing other muscles to become primary movers for elbow flexion.
• Biomechanical Advantage: By leveraging the neutral grip, the hammer curl is superior for targeting the brachialis and brachioradialis, muscles often undertrained by supinated curls alone.

Why Hammer Curls Might Be Considered "Better" for Specific Goals

While "better" is subjective and depends on individual goals, hammer curls offer several distinct advantages that can make them a superior choice for certain outcomes:

• Enhanced Forearm Development: The robust activation of the brachioradialis directly translates to increased forearm mass and strength, which is often neglected in standard bicep-focused routines.
• Increased Overall Arm Thickness: By heavily engaging the brachialis, hammer curls contribute to the overall girth of the upper arm. As the brachialis grows, it pushes the biceps brachii outwards, making the arm appear thicker and fuller, even when relaxed.
• Improved Grip Strength: The involvement of the brachioradialis and other forearm muscles directly enhances grip strength, a crucial component for many compound lifts and daily activities.
• Reduced Bicep Tendon Stress: For individuals experiencing discomfort or pain in the bicep tendon (e.g., bicipital tendinopathy), the neutral grip of the hammer curl can often be more comfortable and less irritating than a supinated grip, allowing for continued training without exacerbating symptoms.
• Complementary Muscle Engagement: Hammer curls target arm flexors that standard bicep curls do not prioritize, leading to a more balanced and comprehensive development of the entire upper arm and forearm musculature.

The Nuance of "Better": Context and Goals

It's crucial to understand that no single exercise is universally "better" than another. The superiority of an exercise is always relative to an individual's specific goals, biomechanics, and current physical condition.

• If your primary goal is to maximize the peak and definition of the biceps brachii, the standard bicep curl with a supinated grip remains indispensable.
• However, if your objective is to achieve overall arm thickness, develop robust forearms, enhance grip strength, or train with less stress on the bicep tendon, then hammer curls offer unique and often superior benefits.

Both exercises are foundational and serve distinct purposes. A well-rounded arm training program will typically incorporate both to ensure comprehensive development of all elbow flexors.

Incorporating Both into Your Routine

For optimal arm development, integrating both hammer curls and standard bicep curls into your training routine is highly recommended.

• Periodization: You might prioritize one over the other for certain training blocks based on your current goals.
• Combination: Perform both exercises within the same workout, perhaps alternating sets or dedicating specific days to each. For example, you could perform 3 sets of bicep curls followed by 3 sets of hammer curls.
• Variety: Utilize different variations (e.g., incline hammer curls, concentration hammer curls, preacher bicep curls) to keep stimulating the muscles in new ways.

Proper Form Considerations

Regardless of the curl variation, maintaining proper form is paramount to maximize muscle activation and minimize injury risk.

• Controlled Movement: Avoid swinging the weight. Focus on a slow, controlled eccentric (lowering) phase.
• Full Range of Motion: Extend the arm fully at the bottom and contract the muscles completely at the top.
• Stable Torso: Keep your core engaged and avoid using momentum from your back or shoulders.

Conclusion

The notion of hammer curls being "better" than bicep curls isn't about one replacing the other, but rather understanding their distinct contributions to arm development. Hammer curls excel at building overall arm thickness by targeting the brachialis and brachioradialis, enhancing forearm development, and improving grip strength—areas where standard bicep curls are less effective. For a truly complete and functional arm musculature, both exercises are indispensable tools in an expert's arsenal, each offering unique benefits that contribute to a strong, well-proportioned, and resilient upper body.