Muscle and Function: The Triceps

On the back of the arm is the Triceps Brachii muscle group. The group is comprised of three muscles that have separate origins and a common insertion.

The Long Head of the triceps originates in the infraglenoid tubercle of the scapula and inserts into the posterior surface of the olecranon process. The long head is a bi-articulate muscle, meaning that it crosses two joints, and as such it has more than one function. At the shoulder joint, it works to help extend and adduct the arm. It also extends the arm at the elbow.

The Medial Head and the Lateral Head both originate from the humeral shaft and insert into the olecranon process. Their only function is to extend the arm at the elbow joint.

At Vertex, we primarily train the triceps using compound movements, such as the decline press and the overhead press. We occasionally isolate the triceps using either manual resistance or an arm extension machine.

Tricep injuries are not too common. Most often, the muscle is strained when rapid elbow extension is used when trying to lift a weight (yet another reason to use slow, controlled movements when resistance training!)

The Tricep group, which comprises a large portion of the upper arm often takes a back seat to the more popular biceps. It is important that when resistance training, each muscle group is worked to its fullest and that its antagonist is also worked equally as hard to ensure that no muscular imbalances develop.