The French Press is a specialized resistance training movement designed to isolate and build the triceps brachii, the muscle group located on the back of the upper arm. This exercise is an overhead triceps extension, often referred to as the skullcrusher, particularly when performed while lying on a bench. It is a popular isolation exercise used in strength and hypertrophy programs because it allows for a focused effort on the elbow-extending muscles. Positioning the arms overhead places a unique stretch on the muscle, which is a powerful stimulus for growth.
The Primary Muscle Target
The triceps brachii is a large, three-headed muscle that makes up the majority of the mass on the back of the upper arm. It is composed of the long head, the lateral head, and the medial head, all of which converge to insert at the olecranon process of the ulna at the elbow joint. The primary function of all three heads is to extend the forearm at the elbow joint.
The long head is unique because it originates from the scapula, meaning it crosses both the shoulder and the elbow joints. When the arm is raised overhead, the shoulder joint is flexed, which stretches the long head of the triceps to its maximum length. This pre-stretching is known to maximize muscle fiber recruitment and activation in this head, making the French Press highly effective for targeting the long head specifically. The medial and lateral heads originate directly on the humerus and also work to extend the elbow, but they are not subject to the same mechanical stretch.
Step-by-Step Execution Guide
To perform the standard lying French Press, begin by lying supine on a flat bench with your feet firmly on the floor for stability. Grasp an EZ curl bar or a straight barbell with an overhand grip, using a grip width that is slightly narrower than shoulder-width. Press the weight up over your chest until your arms are fully extended, but maintain a slight bend in the elbows to keep tension on the triceps. This is the starting position.
The eccentric phase involves slowly lowering the weight by bending only at the elbows, allowing the bar to descend in an arc toward the crown of your head or just behind it. It is important to keep the upper arms perpendicular to the floor and stationary throughout the entire movement. The deliberate, controlled lowering should take several seconds, maximizing the time the triceps spend under tension.
Once the elbows are fully flexed and the triceps are completely stretched, pause momentarily before beginning the concentric phase. The concentric phase requires you to forcefully extend your forearms to press the weight back to the starting position using only your triceps. Avoid the temptation to let your elbows drift forward or backward, as this transfers the effort away from the triceps and onto the shoulder joint.
Common Form Errors and Modifications
A common mistake during the French Press is allowing the elbows to flare outward to the sides as the weight descends. This reduces the stretch on the long head and places stress on the elbow joint. Using excessive weight is another frequent error, often resulting in momentum from the shoulders to complete the lift or causing strain in the wrists. To mitigate joint discomfort and ensure triceps isolation, maintain a fixed upper arm position and choose a weight that allows for a full, controlled range of motion.
The exercise can be modified based on equipment or physical limitations. The lying variation, often called a skullcrusher, can be performed with an EZ bar, which is easier on the wrists due to its angled grips, or with dumbbells. Dumbbells allow for a slightly greater range of motion and independent arm work. Moving from a lying position to a seated or standing overhead position shifts the tension curve. The seated or standing overhead French Press requires greater shoulder stability and often results in a more intense stretch on the long head at the bottom of the movement.