Soleus
Leg & Ankle
Called the 'skeletal muscle heart' because its contractions pump blood back up from your legs while standing.
Function
Plantarflexes ankle (especially with knee bent), postural muscle
Origin
Posterior head and upper shaft of fibula, soleal line of tibia
Insertion
Calcaneus via Achilles tendon
Innervation
Tibial nerve (S1-S2)