Biceps brachii muscle

For other uses, see Biceps.

In human anatomy, the **biceps brachii** is a muscle located on the upper arm. The biceps has several functions, the most important simply being to flex the elbow and to rotate the forearm.

## Terminology

The term *biceps brachii* is a Latin phrase meaning "two-headed [muscle] of the arm", in reference to the fact that the muscle consists of two bundles each with its own origin but with a common insertion point near the elbow.

Note that the word *biceps* is used in both singular and plural: the form *bicep*, although common, is incorrect.

## Anatomy

Proximally, the **short head** of the biceps attaches to (originates from) the coracoid process of the scapula. The tendon of the **long head** passes into the joint capsule at the head of the humerus, and attaches on the scapula at the supraglenoid tubercle.

Distally, biceps attaches to (inserts into) the radial tuberosity, and because this bone can rotate, the biceps also supinates the forearm. The biceps also connects with the fascia of the medial side of the arm, at the bicipital aponeurosis.

Two additional muscles lie underneath the biceps brachii. These are the coracobrachialis muscle, which like the biceps attaches to the coracoid process of the scapula, and the brachialis muscle which connects to the ulna and the humerus.

## Functions

The biceps is tri-articulate, meaning that it works across three joints. The most important of these functions are to flex the elbow and to supinate the forearm.

These joints and the associated actions are as follows:

* Glenohumeral joint (shoulder) - flexion (bringing arm upward by a forward motion)

* Elbow - flexion. Arguably the most functional of the biceps' functions is elbow flexion. This refers to bending the forearm toward the upper arm, resulting in a decrease of angle. More commonly, this is known as the action performed in a biceps curl. The brachialis muscle and brachioradialis muscle are known to aid in this action as well.

* Proximal radioulnar articulation - supination of the forearm. One of the main functions of the biceps is to, along with the supinator muscle, aid in supination of the forearm (turning the palm upwards).

## Training

The biceps can be strengthened in weight training through biceps curls, which is an inefficient bodybuilding exercise.

Chin ups and pull ups will also help with building your biceps.

## Additional images

Biceps brachii.pngLocationArm flex pronate.jpgAn example of an arm flexed in the **pronated** position; with the biceps partially contracted.Arm flex supinate.jpgAn example of an arm flexed in a **supinated** position with the biceps fully contracted.Shoulderjoint.PNGDiagram of the human shoulder jointGray203.pngLeft scapula. Dorsal surface.Gray213.pngBones of left forearm. Anterior aspect.Gray411.pngDeep muscles of the chest and front of the arm, with the boundaries of the axilla.Gray413 color.pngCross-section through the middle of upper arm.Gray414.pngFront of the left forearm. Superficial muscles.Gray525.pngThe brachial artery.Gray809.pngThe right brachial plexus (infraclavicular portion) in the axillary fossa; viewed from below and in front.Nerves of the left upper extremity.gifNerves of the left upper extremity.

## External links

* LUC *bb*
* UWASH *bicepsbrachii*
* *Biceps brachii muscle* at GPnotebook
* SUNY Labs *06:05-0102*
* *Muscles/BicepsBrachii at exrx.net*

ar:العضلة ذات الرأسين العضدية
ca:Bíceps braquial
cs:Dvojhlavý sval pažní
de:Musculus biceps brachii
es:Bíceps braquial
fr:Muscle biceps brachial
id:Otot biceps brachii
it:Bicipite brachiale
he:שריר הזרוע הדו ראשי
hr:Dvoglavi nadlaktični mišić
pam:Dagis-dagisan
la:Musculus biceps brachii
hu:Kétfejű karizom
nl:Musculus biceps brachii
ja:上腕二頭筋
pl:Mięsień dwugłowy ramienia
pt:Bíceps
ru:Двуглавая мышца плеча
sl:Dvoglava nadlaktna mišica
fi:Hauis
sv:Biceps brachii
th:กล้ามเนื้อไบเซ็บ บราคิไอ
zh:肱二頭肌