The triceps brachii muscle, located on the back of the upper arm, is responsible for straightening the elbow joint. This muscle group is composed of three heads: the lateral, the medial, and the long head. The long head is the largest component, and targeting it specifically is necessary for optimal arm development.
The Unique Role of the Long Head
The long head of the triceps is distinct from the other two heads due to its anatomical origin. While the medial and lateral heads originate solely on the humerus, the long head originates on the scapula (shoulder blade). This unique attachment means the long head is a bi-articular muscle, crossing both the shoulder and elbow joints.
The long head’s function extends beyond forearm extension, as it also assists with shoulder extension and adduction. Because it attaches above the shoulder joint, the muscle must be stretched at the shoulder for full activation during elbow extension. Therefore, exercises that place the arm in shoulder flexion—where the arm is raised overhead—are most effective for maximizing long head recruitment.
Maximizing Activation with Overhead Extensions
The most effective exercises for the long head involve moving the arm into an overhead position. This alignment places the muscle in a maximally lengthened state, which stimulates muscle activation and growth. The Seated Dumbbell Overhead Extension is a prime example, performed by holding a single dumbbell with both hands and pressing it directly overhead.
To execute this movement, begin with the weight fully extended overhead, then slowly lower it behind your head by bending only the elbows. Keep the upper arms close to the head and avoid letting the elbows flare out. Lowering the weight until the forearms are parallel to the floor, or until a deep stretch is felt, ensures the long head is fully engaged at the bottom.
The Cable Rope Overhead Extension offers similar benefits but provides constant tension throughout the range of motion, which aids hypertrophy. For this variation, set a pulley low and face away from the machine, pulling the rope over your head to the starting position. Maintain a braced core and keep the elbows pointing forward as you extend the arms upward. This constant resistance, especially during the eccentric (lowering) phase, ensures continuous loading on the long head.
Alternative Exercises Utilizing Stretch and Angle
While overhead movements are highly effective, alternative exercises using specific angles or stretches can also target the long head and offer variety. The Incline Dumbbell Skull Crusher is an excellent option, performed on a bench set to a 30 to 45-degree angle. This slight incline slightly flexes the shoulder joint, which pre-stretches the long head and increases its activation compared to a flat bench variation.
Using dumbbells allows for a neutral grip (palms facing each other), which some find more comfortable and effective for long head recruitment. The movement involves lowering the dumbbells toward the sides of the head, maximizing the stretch before forcefully extending the arms. Ensure the elbows remain pointed toward the ceiling throughout the repetition to keep tension on the triceps.
Another effective technique involves using a low-pulley cable extension while leaning the torso forward, positioning the elbow slightly behind the body. This angle, often seen in triceps kickback variations, also creates a favorable stretch on the long head. Incorporating these varied angles ensures the largest head of the triceps is adequately stimulated for growth and strength.