Gastrocnemius

Origin: Medial and lateral condyles of the femur (thigh bone).

Insertion: Calcaneus (heel bone) via the Achilles tendon.

Action: The gastrocnemius is the primary muscle involved in ankle plantar flexion. It is especially active during activities like walking, running, and jumping.

Soleus

Origin: Head of the fibula and upper third of the tibia (shinbone).

Insertion: Calcaneus (heel bone) via the Achilles tendon.

Action: The soleus is also involved in ankle plantar flexion but is more active when the knee is flexed, such as during standing or when performing exercises like calf raises with bent knees.

Plantaris

Origin: Lateral supracondylar ridge of the femur (above the lateral condyle of the femur).

Insertion: Calcaneus (heel bone) via the Achilles tendon.

Action: The plantaris muscle assists in ankle plantar flexion and also aids in knee flexion.