Short HeadShort Head of Biceps Brachii

armsCaput breve musculi bicipitis brachii

The short head of the biceps runs from the front of the shoulder blade down the inner side of the upper arm. It is the half of the biceps that adds thickness rather than height.

The short head starts on the coracoid process — the forward-pointing hook at the top of the shoulder blade that you can feel through the front of the shoulder — and runs down the inside of the upper arm, sharing the coracoid with the pectoralis minor and coracobrachialis.

It does the same two things as the long head, bending the elbow and turning the palm up, and the two are joined so completely that no movement uses one without the other. What differs is the effect on the shape of the arm: the short head sits on the inner side, so developing it adds width to the arm seen from the front rather than height seen from the side.

Because it takes a more direct route to the shoulder joint than the long head, its position changes less with arm position. It is the head that keeps contributing when the elbows are forward and the long head has slackened.

Training notes

Curls with the elbows in front of the torso favour it. Preacher curls, concentration curls and any curl performed with the upper arm resting forward all shorten the long head at the shoulder and leave more of the work here.

A wider grip on a barbell curl also brings it in slightly, by moving the forearm outward relative to the elbow. The effect is real and small, and not worth reorganising a program around.

As with the peak, the width of the arm is a matter of where the muscle sits as much as how big it is. What training reliably changes is size.

Anatomy

Origin
  • Apex of the coracoid process of the scapula
Insertion
  • Radial tuberosity, through the shared biceps tendon
Actions
  • Supinates the forearm
  • Flexes the elbow
  • Assists flexion and adduction of the arm at the shoulder
Innervation
Musculocutaneous nerve (C5–C6)

Exercises

Antagonists

Synergists