Triceps: How to Effectively Target the Medial Head for Arm Development

How do you hit the small head of your triceps?

To effectively target what is colloquially known as the "small head" of the triceps—anatomically the medial head—focus on exercises that emphasize elbow extension with the elbows tucked close to the body, utilizing a full range of motion, and often incorporating a supinated or neutral grip for enhanced engagement.

Understanding Triceps Anatomy: The Three Heads

The triceps brachii muscle is aptly named, derived from the Latin "tri" (three) and "ceps" (heads), indicating its three distinct parts: the long head, the lateral head, and the medial head. While all three heads work synergistically to extend the elbow, their unique anatomical origins and insertions mean they are recruited differently depending on arm position and exercise mechanics.

• The Long Head: Originates from the infraglenoid tubercle of the scapula (shoulder blade). Due to its origin across the shoulder joint, it is the only triceps head involved in both elbow extension and shoulder adduction/extension. Exercises where the arm is overhead or extended behind the body tend to emphasize the long head.
• The Lateral Head: Originates from the posterior surface of the humerus, superior to the radial groove. It is the most superficial and often contributes significantly to the "horseshoe" shape of a well-developed triceps. This head is strongly activated in movements where the elbow is extended against resistance.
• The Medial Head (The "Small Head"): Originates from the posterior surface of the humerus, inferior to the radial groove. This head lies deepest, beneath the long and lateral heads, and is often less visible. It is active in all elbow extension movements but is particularly engaged in the final degrees of extension and when the elbows are kept close to the torso. It is often referred to as the "workhorse" of the triceps due to its consistent activation across various extensions.

Why "Isolating" the Medial Head is Challenging

While the desire to "isolate" a specific muscle head is common, true isolation is largely a misconception in functional anatomy. Muscles, especially those with multiple heads, work together as a unit. However, we can certainly emphasize or preferentially activate certain heads based on biomechanical principles.

• Functional Overlap: All three triceps heads are primarily responsible for elbow extension. This means that in any elbow extension exercise, all three heads will be active to some degree.
• Recruitment Patterns: Electromyography (EMG) studies show varying activation levels for each triceps head across different exercises. The medial head tends to have a more consistent activation pattern throughout the full range of elbow extension, often peaking towards the end range. The lateral head is often more active in movements requiring higher force, and the long head is more active when the arm is overhead.
• Anatomical Position: The medial head's deeper position means it's less visibly prominent, leading some to perceive it as "smaller" or harder to develop, when in reality it's just less superficial.

Principles for Emphasizing the Medial Head

To preferentially engage the medial head of the triceps, consider these biomechanical principles:

• Elbow Position: Keeping the elbows tucked close to the body minimizes the involvement of the long head (which acts as a shoulder extensor/adductor) and places more direct stress on the lateral and medial heads for pure elbow extension.
• Full Range of Motion: The medial head is consistently active throughout elbow extension, but its contribution can be particularly pronounced in the final degrees of extension. Ensuring a full lockout (without hyperextension) can maximize its engagement.
• Grip Orientation: While not as definitive as elbow position, some evidence suggests that a neutral grip (palms facing each other) or even a supinated (underhand) grip can slightly shift emphasis towards the medial head by altering forearm rotation and subsequent triceps recruitment.
• Mind-Muscle Connection: Consciously focusing on squeezing the triceps, particularly the area around the medial head, during the concentric (lifting) phase can enhance neural drive and recruitment.

Key Exercises to Target the Medial Triceps

Based on the principles above, the following exercises are excellent choices for emphasizing the medial head:

• Cable Rope Pushdowns:
  • Execution: Stand facing a cable machine, grasp a rope attachment with a neutral grip (palms facing each other). Keep elbows tucked tightly to your sides. Extend your forearms downwards, pushing the rope apart at the bottom to achieve a full contraction and lockout.
  • Why it works: The neutral grip and the ability to maintain tucked elbows create a strong line of pull directly into elbow extension, emphasizing the medial and lateral heads.
• Straight Bar Pushdowns (with a narrow, pronated grip):
  • Execution: Similar to rope pushdowns, but use a straight or V-bar. Maintain a pronated (overhand) grip slightly narrower than shoulder-width. Keep elbows pinned to your sides and fully extend the bar downwards.
  • Why it works: The consistent resistance from the cable and the fixed elbow position provide excellent tension on the medial and lateral heads.
• Dumbbell Kickbacks:
  • Execution: Lean forward with your torso nearly parallel to the floor, supporting yourself with one hand on a bench. Hold a dumbbell in the other hand, keeping your upper arm parallel to the floor and elbow bent at 90 degrees. Extend your forearm straight back until your arm is fully extended.
  • Why it works: This exercise effectively isolates the elbow extension movement, with the upper arm fixed and the elbow tucked, leading to strong medial head activation, especially at the peak contraction. Use lighter weights to maintain strict form.
• Close-Grip Bench Press:
  • Execution: Lie on a flat bench, grasping the barbell with a pronated grip slightly narrower than shoulder-width (typically inside shoulder-width, but not so narrow it causes wrist pain). Lower the bar to your lower chest/upper abdomen, keeping your elbows tucked close to your body. Press the bar back up to full extension.
  • Why it works: As a compound movement, it allows for heavier loads. The close grip and tucked elbows significantly increase triceps involvement, with high activation of all three heads, including the medial head.
• Reverse-Grip (Supinated) Triceps Pushdowns:
  • Execution: Attach a straight or EZ bar to a high cable pulley. Grasp the bar with a supinated (underhand) grip, about shoulder-width apart. Keep your elbows tucked to your sides and extend your forearms downwards, focusing on squeezing the triceps.
  • Why it works: Some EMG studies suggest that a supinated grip may lead to slightly greater activation of the medial head compared to a pronated grip, likely due to altered forearm rotation mechanics.

Programming for Comprehensive Triceps Development

To ensure balanced and complete triceps development, incorporate a variety of exercises that target all three heads.

• Include Overhead Movements: For long head emphasis (e.g., overhead dumbbell extensions, cable overhead extensions).
• Include Pressing Movements: For overall mass and strength, engaging all heads (e.g., close-grip bench press, dips).
• Include Pushdown/Kickback Movements: For medial and lateral head emphasis, and for isolation (e.g., cable pushdowns, dumbbell kickbacks).
• Vary Rep Ranges: Utilize both heavier loads for strength (6-10 reps) and moderate loads for hypertrophy (10-15 reps) to stimulate growth through different pathways.
• Prioritize Form: Always choose proper technique over heavy weight to maximize target muscle activation and minimize injury risk.

Conclusion: A Holistic Approach

While the concept of "hitting the small head" of the triceps often refers to specifically targeting the medial head, it's crucial to understand that all three heads work in concert. True isolation is anatomically challenging, but through strategic exercise selection and precise execution, you can emphasize the medial head's contribution. By incorporating exercises that keep the elbows tucked, utilize full extension, and potentially involve neutral or supinated grips, you can ensure comprehensive and balanced triceps development, leading to stronger, more defined arms. Remember, consistency, progressive overload, and proper form are paramount for achieving your fitness goals.