Because the triceps make up such a large proportion (approximately 60%) of the muscle mass on the upper arm, when it comes to bringing up overall arm size, focusing on the tri’s is a smart plan. Of the three triceps heads — long, lateral and medial — the long head makes up the majority of the mass and adds the most size to the upper arm when viewed from side. One of the best ways to hit the long head is with barbell incline triceps extensions. To perform this exercise, sit back on an incline bench set to a 45-degree angle or higher. Hold a barbell overhead so that your arms are perpendicular to the floor. Keeping your upper arms still, bring the barbell down to the back of the top of your head by bending your arms only at the elbow joints. Return the bar to the start position by extending your arms at the elbows.
To emphasize the long head of the triceps, perform barbell incline triceps extensions early in your workout after multijoint exercises, such as close-grip bench presses. To really bring up the long head, add a second exercise, such as cable overhead triceps extensions, later in the workout.
FORM AND FUNCTION
Since the triceps long head attaches to the scapula, you emphasize it more when you do triceps extensions with your arms overhead, as in incline extensions or dumbbell overhead extensions. Bringing the arms overhead stretches the long head. By stretching the muscle, it contracts with more force, which allows the long head to take the brunt of the load during these extensions.
