Your calf muscle sits in the back of your lower leg. It starts below your knee and extends to your ankle. It allows you to walk, run, jump and flex your foot. It also helps you stand up straight.
The calf muscle is in the back of your lower leg, behind your shin bone. It actually includes three muscles. Together, the muscles help you walk, run, jump, stand on your toes and flex your foot (lift your toes up toward your knee).
Your calf muscle supports you when you stand and enables you to move your foot and your lower leg. It propels (pushes) you forward when you walk or run. It also allows you to jump, rotate your ankle, flex your foot and “lock” your knee.
Your calf muscle consists of two main muscles — the gastrocnemius and the soleus. Because these two muscles come together above your heel and attach to the Achilles tendon, some providers refer to the gastrocnemius and soleus as one large muscle with two sections.
In addition to these two large muscles, a small muscle called the plantaris runs between the gastrocnemius and soleus down the length of the lower leg. Providers call these three muscles the triceps surae. But not everyone has a plantaris muscle. About 10% of people only have two larger muscles.
The main muscles in the calf are:
This muscle is just under your skin at the back of the lower leg. Because the gastrocnemius is close to the skin’s surface, you can often see its outline. It forms the bulk of your calf muscle.
The top part of the gastrocnemius has two heads that start on the inside and the outside of the femur (thighbone). The gastrocnemius goes down the back of the leg and attaches to the Achilles tendon. Gastrocnemius strains are common because the muscle connects to two joints (the knee joint and the ankle joint).
The soleus is a wide, flat muscle that sits slightly deeper than the gastrocnemius. It starts just below your knee, runs down your lower leg and connects to the Achilles tendon above the heel. Soleus injuries are less common because the muscle only crosses the ankle joint.
The soleus connects to your tibia and fibula (the bones in your lower leg). Together with your gastrocnemius, the soleus helps you walk, run and jump. It also helps your legs support you so you can maintain good posture.
As part of your musculoskeletal system, the gastrocnemius and soleus are a type of muscle called skeletal muscle. Many individual fibers make up skeletal muscles. These fibers bundle together to create a striated (striped) appearance.
Conditions that affect the calf muscle include:
Calf muscle strain is one of the most common muscle strain injuries among athletes. People who play sports that require sprinting and quick footwork have an increased risk of this type of injury.
Leg cramps are also very common, and they’re more likely to happen as you age. Providers estimate that about 75% of people over age 50 have had leg cramps at some point.
Problems in the calf muscle can cause:
To avoid problems with your calf muscles, you should:
If you have severe or sudden calf pain that doesn’t improve after a day or two of rest, call your provider. Calf pain and other symptoms of a muscle strain may actually be signs of a serious medical condition, such as a blood clot, deep vein thrombosis (DVT), nerve damage or Achilles tendonitis.
Get help right away if you have:
A note from Cleveland Clinic
Your calf muscle helps you move your lower legs, feet and ankles. It allows you to flex your feet, walk, run and leap. It also supports and stabilizes your legs and enables you to stand up straight. Calf pain from muscle strains and leg cramps is very common. You can keep your calf muscles strong by staying active, drinking plenty of water and warming up before you exercise. Call your provider if you have calf tenderness that doesn’t get better in a day or two — or if you have swelling, redness or severe pain.
Last reviewed by a Cleveland Clinic medical professional on 08/05/2021.
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