- The first muscle is the commonly known gastrocnemius (the large bulkier muscle) in your lower limb.
- The second muscle is your soleus.
Why is this muscle so important in runners?
When you run, your body has to support up to 3-8x our own body weight! Both of your calf muscles have a very important role in walking and running and in particular our soleus. This particular muscle works to flex the foot so that the toes point downwards (plantar flexion) and further plays an important role in ankle stability and standing posture to prevent you from falling forward.
The soleus muscle does not have the power that our larger calf muscle (gastrocnemius) has, due to it primarily made up of slow twitch fibres and therefore this muscle is importance for endurance. The soleus bears a lot of load during running, much more than the larger gastrocnemius muscle and is often called the skeletal-muscle pump because of its ability to pump deoxygenated blood back from your legs to your heart.
For runners the soleus:
- The soleus drives you forward during running and walking
- Bears most of the load from running
- Is made up of slow twitch fibres and therefor very resistant to fatigue
