Why is the soleus muscle referred to as the “second heart”?

ANSWER:

The soleus muscle, located in the lower leg, plays a vital role in blood circulation. It is often nicknamed the "second heart" because of its ability to pump blood from the legs back to the heart. This is crucial when we are standing or sitting for extended periods, as blood can pool in the lower limbs. The contracting action of the soleus muscle helps to propel the blood upward, combating the effects of gravity. This muscle's pumping action is essential for maintaining venous blood flow, reducing the risk of clot formation, and preventing swelling in the legs. Keeping the soleus muscle strong and active is beneficial for cardiovascular health and can improve overall endurance and stamina.