Select Page

Part of 100+ Q&A about legs. See all.

Is there anything special or unique about the calf?

The calf is made up of two superficial muscles: the upper gastrocnemius; and the lower soleus. These are located at the back of your lower leg and join together to become your achilles tendon and attach onto your heel.


The bigger, upper part of your calf. This gastroc has two heads – a lateral (outside), and medial (inside). They both come from the back of your femur (thigh bone) and form into your achilles tendon. 

The gastroc is mostly made up of Type II fibres, or fast-twitched fibres. This means this muscle is important in powerful explosive movements such as sprinting, jumping and changing direction. 

Along with the soleus muscle, the gastrocnemius forms half of the calf muscle. Its function is plantar flexing the foot at the ankle joint and flexing the leg at the knee joint. The gastrocnemius is primarily involved in running, jumping and other “fast” movements of leg, and to a lesser degree in walking and standing. This specialization is connected to the predominance of white muscle fibers (type II fast twitch) present in the gastrocnemius, as opposed to the soleus, which has more red muscle fibers (type I slow twitch) and is the primary active muscle when standing still, as determined by EMG studies.

The gastrocnemius muscle is prone to spasms, which are painful, involuntary contractions of the muscle that may last several minutes.

A severe ankle dorsiflexion force may result in an injury of the muscle, commonly referred to as a “torn” or “strained” calf muscle, which is acutely painful and disabling.

The gastrocnemius muscle may also become inflamed due to overuse. Anti-inflammatory medications and physical therapy (heat, massage, and stretching) may be useful.

Anatomical abnormalities involving the medial head of gastrocnemius muscle result in popliteal artery entrapment syndrome.

Gastrocnemius muscle – animation.gif


This is the smaller of the two calf muscles. It sits underneath your gastrocnemius and starts from your tibia and fibula (your shin bones) rather than your femur. Then it joins with the gastrocnemius to become your achilles tendon. 

Your soleus is mostly made of Type I fibres, or slow-twitch fibres. You may think this makes it less important. But it certainly isn’t. It means the soleus has better endurance, i.e. it won’t fatigue and will be there to support you. Literally! If you didn’t have your soleus you would fall forward and face-plant!

In fact, They actually have multiple important roles. Explosive power, running, as a blood pumper, support your posture and injury prevention!

There are many injuries that can be prevented if you have decent calf strength. Some of these include: 

  • Calf tears and strains 
  • Sprained ankles 
  • Plantar fasciitis 
  • Medial Tibial Stress Syndrome (shin splints) 
  • Patellofemoral Pain 
  • Tendinopathies of the ankle and foot 
  • Tendinopathies of the knee 
  • Stress Fractures

With a strong calf complex the injuries above are less likely to happen. Some however aren’t preventable. For example; if you step in a gutter and sprain your ankle. Despite this being out of your control, having decent calf strength as a base could decrease the severity of your injury and even speed up your recovery! 

On the other hand, if you already have an injury don’t fear! Not only is calf strength important in prevention, it is also vitally important to rehabilitate many injuries!

Why is Calf Strength So Important? 

Your calf muscles propel you forward with every single step, they absorb load with each impact and they support the rest of your lower limb and body. 

By increasing your calf strength you will: 

  • Become faster 
  • Be able to run for longer 
  • Keep a more consistent pace while running 

Be able to jump higher

The talus (ankle bone) is the second largest of the tarsal bones and sits atop the calcaneus to form the subtalar joint. The tibia and fibula adjoin it on either side to form the tibiotalar joint. The talus forms a joint with four bones: tibia, fibula, calcaneus, and navicular.

All about legs topics Kneecap functions | Nerves in soles | Acupuncture on soles |Leg muscles | Leg bones | Feet bones | Toes & fingers | Feet flexibility | Feet skin | Feet arches | Men and women leg shapes |Knee functions | Hair on legs | Role of toes | Yoga for legs | Unique about calf | Unique about femur | Unique about sartorius | Feet acupuncture | Sizes of feet | Legs start & end points | Joints in feet | Foot reflexology | Foot sweat glands | Leg injuries in babies & children | Flat feet problems | Foot length & height | Toe stubbing | Knee joints & elbow joints| Kneecap anatomy | Kneecaps at birth | Foot length variation| Human foot sizes | Why five toes | Shoe fits | Time to buy shoes | Attraction of long legs | Posture while checking shoe sizes |Feet size of men and women | Leg insurance | Human leg rituals | Human and mammalian legs | Leg posture psychology | Running & leg muscles | Standing still & walking | First footwear | Shoe size history | Shoes of men & women | Ankle sprains and sports | Smell of shoes and socks | Cushioning the feet | Lifetime walking | Foot problems for women | Toes and genitals | Leg prosthetics | Ticklish feet | Toe wrestling | Fewer than five toes | More than five toes | Toenail & fingernail growth | Toenails & fingernails | Trying out footwear for one foot while buying | Tight clothing leg ailments | High heels leg ailments | Small footwear sizes for women | Leg transplant feasibility | Legs & celebrities | Leg parts involved in walking or running | Re-purposing or reusing old shoes | Time to buy shoes | Ill-fitting shoe problems | Legs & feet world records | Walking leg postures | Crossing legs while sitting | Leg posture lying down | Leg posture standing | Leg posture sitting | Strange leg ailments | Taking care of feet | Taking care of knees | Can elephants jump | Connection between feet & body problems | Leg health for corporate professionals | Science & study of legs | Walking barefoot at home| Prosthetic leg limitations | Evolution and leg length | Reasons for long legs | Top leg problems | Uncommon roles for legs & feet | When are legs strongest | Taking care of thighs | Heel fat pads | Ball of the foot | Population with leg diseases | Leg arteries & veins | Leg muscles