Arm · Skeletal muscle
Triceps (Triceps Brachii)
The triceps is the muscle at the back of the upper arm that straightens the elbow. It works opposite to the biceps and powers pushing movements.
What it is
The triceps brachii is a three-headed muscle covering the back of the upper arm.
Where it is
The back of the upper arm, between the shoulder and the elbow.
What it does
Straightens (extends) the elbow; helps stabilise the shoulder.
Everyday use
Pushing a door, getting up from a chair with your arms, and throwing all use the triceps.
When things go wrong
Common problems affecting the triceps (triceps brachii)
- Triceps strain
- Tendinitis at the elbow
- Triceps tendon rupture (uncommon)
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
Balanced strengthening of both the front and back of the arm and gradual training loads keep the triceps healthy.
Did you know?
An interesting fact
The triceps makes up around two-thirds of the muscle bulk of the upper arm — more than the biceps.
Answers
Triceps (Triceps Brachii): frequently asked questions
What does the triceps do?
The triceps straightens the elbow and powers pushing movements — the opposite action to the biceps.
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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