Why is our Calf Muscle called our 2nd Heart?

Because of the role they play in helping to pump venous blood from the lower extremities. Our calf muscles (soleus muscles) play an important role in pumping blood through venous circulation and are therefore known as the peripheral heart. When we contract our calf muscles, the veins inside force the blood to flow upwards towards our heart. The venous system refers to the network of veins that work to deliver deoxygenated blood back to your heart.