The triceps brachii muscle, located on the back of the upper arm, is composed of three distinct sections: the medial, lateral, and long head. This muscle group is responsible for approximately two-thirds of the total muscle mass in the upper arm, making its development important for overall arm size. The long head is the largest of these three sections and is the primary focus for individuals looking to maximize arm girth. Specific training methods that target the long head are required for optimal growth due to its unique anatomy.
Unique Role of the Long Head
The triceps long head possesses an anatomical structure that sets it apart from the medial and lateral heads. Both the medial and lateral heads originate on the humerus, the upper arm bone, meaning they only cross the elbow joint. The long head, however, originates on the infraglenoid tubercle of the scapula, or the shoulder blade.
Because of this attachment point on the scapula, the long head is the only part of the triceps that crosses both the elbow and the shoulder joints. This dual-joint function means the long head contributes to both elbow extension and shoulder extension or adduction. To fully engage and stretch this head under load, the muscle must be placed in a position of shoulder flexion, where the arm is elevated overhead.
This overhead position forces the long head to lengthen significantly. Research suggests this mechanical requirement maximizes muscle activation and promotes muscle growth more effectively than exercises performed with the arm by the side. Training a muscle in its lengthened position is an effective strategy for hypertrophy, providing the basis for selecting specific movements that prioritize the long head.
Isolation Movements for Maximum Stretch
The long head is targeted by selecting movements that put the triceps under load while the arm is in an overhead position. The Overhead Dumbbell Extension is a primary exercise for this purpose, where the arm is fully flexed at the shoulder to create maximum stretch in the long head. This movement can be performed with a single dumbbell held in both hands or with a dumbbell in each hand. The weight is lowered deep behind the head, ensuring the long head works at its longest muscle length.
The Rope Overhead Extension is a cable variation where the pulley is set low and the lifter faces away from the machine. Stepping out to create constant tension, the exerciser extends the elbows overhead. The rope attachment allows the hands to separate slightly at full extension, which can increase the intensity of the contraction. This provides a consistent resistance profile that differs from free weights, maintaining tension even at the top of the movement.
Another beneficial movement is the Lying Triceps Extension, often called a Skull Crusher, which uses a bench and an EZ-bar or dumbbells. While the arm is not completely overhead, the starting position angles the humerus back slightly toward the head, creating a significant stretch on the long head. The bar is lowered toward the crown of the head, focusing only on bending at the elbow joint. Using a slight decline bench for this movement can further increase the angle of shoulder flexion, intensifying the stretch and long head activation.
Optimizing Execution and Technique
Achieving long head growth requires attention to the execution of the selected movements. During overhead extensions, keep the elbows pointed forward, or “tucked toward the ears,” rather than allowing them to flare out excessively. Excessive elbow flare shifts tension away from the long head and reduces the degree of stretch achieved. Maintaining a stable shoulder position prevents other muscles from taking over the movement.
The eccentric, or lowering, phase of the lift should be controlled and slow, typically lasting three to four seconds. This controlled descent allows the long head to be loaded effectively while it is lengthening, a mechanism linked to muscle hypertrophy. The entire range of motion must be utilized in every repetition, especially the deep stretch at the bottom. This focus ensures the long head is worked across its entire functional length.
Minimize momentum and focus on the muscle doing the work to maximize the mind-muscle connection. During the concentric, or lifting, phase, the elbow should be fully extended without locking out aggressively, which keeps tension on the triceps. For cable movements, a slight rotation of the wrist at full extension can enhance the peak contraction.
Integrating Long Head Training Volume
For sustained hypertrophy, long head movements must be strategically integrated into the weekly training schedule. Training the triceps two to three times per week is recommended, as this frequency allows for adequate volume distribution and recovery. Splitting the total weekly sets across multiple sessions leads to better muscle adaptations than performing all the volume in a single workout.
A practical total volume range for direct triceps work is between 10 and 20 working sets per week, though some individuals may benefit from volumes exceeding 20 sets. It is beneficial to place the long head-specific exercises, such as overhead extensions, early in the workout when the muscle is fresh. This prioritization ensures the highest quality of work is applied to the targeted head.
The optimal repetition range for hypertrophy is between 8 and 15 repetitions per set, performed near muscle failure. Utilizing this moderate-to-high rep range helps to accumulate the necessary volume and metabolic stress for muscle growth. Consistent application of appropriate volume and frequency will result in increased size and density.