Leg · Skeletal muscle
Gastrocnemius (Calf Muscle)
The gastrocnemius is the main calf muscle at the back of the lower leg. It points the foot down and pushes you off the ground when walking, running and jumping.
What it is
The gastrocnemius is the large, two-headed muscle that gives the calf its shape, joining the deeper soleus muscle to form the Achilles tendon.
Where it is
The back of the lower leg, between the knee and the heel.
What it does
Points the foot down (plantarflexion) and helps bend the knee; drives push-off in walking and running.
Everyday use
Walking, running, jumping, standing on tiptoe and pushing a car pedal all use the calf muscles.
When things go wrong
Common problems affecting the gastrocnemius (calf muscle)
- Calf strain ("tennis leg")
- Cramps
- Achilles tendon problems
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
Stretching, gradual training, and staying hydrated help prevent calf strains and cramps.
Did you know?
An interesting fact
The gastrocnemius connects to the heel through the Achilles tendon — the thickest and strongest tendon in the body.
Answers
Gastrocnemius (Calf Muscle): frequently asked questions
What does the calf muscle do?
The calf muscle (gastrocnemius) points the foot down and pushes you off the ground when walking, running and jumping.
Why do calves cramp?
Calf cramps can come from tiredness, dehydration, mineral imbalance or staying in one position. Occasional cramps are common; frequent or severe ones are worth discussing with a GP.
Related muscles
Explore the leg
Sources
Where this is drawn from
- NHS — Muscles and movement
- Gray's Anatomy for Students
- TeachMeAnatomy — muscular system
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