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Muscle guide · Lower legs

Gastrocnemius

Also called calf muscle, gastroc

The gastrocnemius is the two-headed muscle that forms the visible bulge of the calf, the outermost muscle at the back of the lower leg. Its heads start just above the knee and join the soleus in the Achilles tendon.

Mostly fast-twitch, it is the calf's power muscle, used for jumping, sprinting and the push-off of each stride, while the soleus underneath handles long, steady work.

5 exercises2 stretches7 with 3D demos10 sourcesUpdated 17 October 2026

Where the gastrocnemius is and what it does

Shaded: the calves area. It marks the region, not the exact outline of the gastrocnemius.
Starts at (origin)
Two heads on the back of the thigh bone, just above the knee.Medial and lateral femoral condyles
Attaches to (insertion)
The heel bone, through the Achilles tendon it shares with the soleus.Posterior calcaneus via the calcaneal (Achilles) tendon
What it does
  • Points the foot and lifts you onto your toes, most strongly with the knee straight.Ankle plantarflexion
  • Helps bend the knee, because it crosses it.Assists knee flexion
  • Supplies fast, forceful push-off: jumping, sprinting.Predominantly fast-twitch, high-force plantarflexion
Nerve supply
Tibial nerve (S1, S2).

Sources 1, 2, 3, 4

Exercises for the gastrocnemius

In a 12-week trial, standing (straight-knee) calf raises grew the gastrocnemius far more than seated raises: about 9 to 12% against under 2%.

Slow calf raise demonstrated on the 3D figure3D demoSlow calf raiseBeginner · A wallSingle-leg calf raise from a step demonstrated on the 3D figure3D demoSingle-leg calf raise from a stepIntermediate · A step + A wallEccentric heel drop demonstrated on the 3D figure3D demoEccentric heel dropIntermediate · A stepDonkey calf raise demonstrated on the 3D figure3D demoDonkey calf raiseIntermediate · Other / check instructionsAnkle bounces (mini pogo) demonstrated on the 3D figure3D demoAnkle bounces (mini pogo)Beginner · No equipment

Stretches for the gastrocnemius

Keep the back knee straight; bending it slackens the gastrocnemius and moves the stretch to the soleus. A common prescription is 30 seconds, 10 times.

Wall calf stretch (gastrocnemius) demonstrated on the 3D figure3D demoWall calf stretch (gastrocnemius)Beginner · A wallCalf Stretch Hands Against Wall demonstrated on the 3D figure3D demoCalf Stretch Hands Against WallBeginner · Other / check instructions

Problems linked to the gastrocnemius

Calf strain ('tennis leg')

A tear in the gastrocnemius, most often its inner (medial) head, felt as sudden pain at the back of the calf and a weak push-off. It is common after 40 and named for how often it happens in racquet sports.

Sources 3, 5

Achilles tendinopathy

Pain in the Achilles tendon itself, a few centimetres above the heel where its blood supply is poorest, or where it attaches to the heel. Tight calves add stress at the attachment. Eccentric heel drops are a standard exercise for the mid-tendon type.

Sources 6, 7

Myths worth dropping

Each grade rates the evidence for the correction.

Stretching before exercise prevents calf and Achilles injuriesMixed evidence

Across 25 randomised trials in sport, stretching programmes did not lower injury rates, while strength training cut them to about a third. Stretch for range of motion and comfort, not as injury insurance.

For the Achilles, pre-activity calf stretching is described as possibly helpful, which is as far as the evidence goes.

Sources 9, 10, 6

Routines that train it

Post-run stretches

Seven stretches for after a run: calves, soleus, quads, hip flexors, hamstrings and glutes.

10 minBeginner7 movesA wall

Runner's warm-up

An 8-minute dynamic warm-up for runners: ankle and hip mobility, lunges, skips and pogo hops.

8 minIntermediate8 movesA wall

Leg day workout (gym)

A gym leg day: back squats, leg press, leg curls, Bulgarian split squats, leg extensions and calf raises.

55 minIntermediate9 movesA wall, A barbell

Questions people ask

What does the gastrocnemius do?

It points the foot and lifts you onto your toes, especially with the knee straight, helps bend the knee, and powers push-off in jumping and sprinting.

How do you build the gastrocnemius?

Standing calf raises with straight knees. In a 12-week trial they grew it several times more than seated raises.

What is the difference between the gastrocnemius and the soleus?

The gastrocnemius is the outer, two-headed calf muscle that crosses the knee and is built for power. The soleus lies underneath, does not cross the knee, and is built for endurance.

Muscles it works with

Sources

  1. StatPearls · Anatomy, Bony Pelvis and Lower Limb: Gastrocnemius Muscle (2026)
  2. StatPearls · Anatomy, Bony Pelvis and Lower Limb: Calf (2026)
  3. StatPearls · Anatomy, Bony Pelvis and Lower Limb: Leg Posterior Compartment (2026)
  4. StatPearls · Anatomy, Bony Pelvis and Lower Limb: Tibial Nerve (2026)
  5. StatPearls · Gastrocnemius Strain (2023)
  6. StatPearls · Achilles Tendinopathy (2026)
  7. AAOS OrthoInfo · Achilles tendinitis
  8. Kinoshita 2023 · Standing vs seated calf-raise training and calf muscle growth (Front Physiol)
  9. Lauersen 2014 · Exercise to prevent sports injuries: strength training vs stretching (meta-analysis of RCTs, Br J Sports Med, abstract)
  10. Thacker 2004 · The impact of stretching on sports injury risk (systematic review, Med Sci Sports Exerc, abstract)

Anatomy and movement education, not a diagnosis or treatment plan. If you have pain that follows an injury, is severe or getting worse, or comes with numbness, weakness or swelling, get it assessed. Health disclaimer.