Arm · Skeletal muscle
Biceps (Biceps Brachii)
The biceps is the muscle at the front of the upper arm that bends the elbow and turns the palm upwards. It is the muscle people flex to "make a muscle".
What it is
The biceps brachii is a two-headed muscle running down the front of the upper arm, from the shoulder blade to the forearm.
Where it is
The front of the upper arm, between the shoulder and the elbow.
What it does
Bends (flexes) the elbow and rotates the forearm so the palm faces up (supination); also helps at the shoulder.
Everyday use
Lifting and carrying, picking things up, and turning a doorknob or screwdriver all rely on the biceps.
When things go wrong
Common problems affecting the biceps (biceps brachii)
- Biceps tendon strain or rupture
- Tendinitis at the shoulder
- Muscle strain from overloading
Education and reference only. This explains the anatomy in plain terms and is not a diagnosis. Sudden severe symptoms — such as crushing chest pain or collapse — are an emergency; call 999.
Looking after it
Keeping it healthy
Warming up before exercise, building strength gradually, and not lifting beyond your capacity reduce the risk of biceps injuries.
Did you know?
An interesting fact
A ruptured biceps tendon can cause a visible bulge in the arm known as a "Popeye" sign.
Answers
Biceps (Biceps Brachii): frequently asked questions
What does the biceps do?
The biceps bends the elbow and turns the palm upwards. It is used whenever you lift or carry something.
What is a "Popeye" arm?
It is the bulge that can appear when a biceps tendon ruptures and the muscle bunches up — named after the cartoon character. It should be assessed by a clinician.
Related muscles
Explore the arm
Sources
Where this is drawn from
- NHS — Muscles and movement
- Gray's Anatomy for Students
- TeachMeAnatomy — muscular system
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