12/15/2025
The calf muscles, primarily the gastrocnemius and soleus, are often referred to as the "second heart" due to their critical role in ensuring efficient blood circulation, specifically the venous return of blood from the lower extremities back to the main heart. The heart pumps oxygen-rich blood down through the arteries, but getting the oxygen-depleted blood back up from the legs—against the force of gravity—requires assistance.
This assistance is provided by the calf muscle pump. Every time the calf muscles contract, such as during walking, running, or even subtle movement, they squeeze the deep veins in the lower legs. This compression acts like a pump, pushing the blood upward. The veins contain one-way valves that prevent the blood from flowing backward, ensuring that the blood only travels toward the heart.
An efficiently working calf pump is vital for overall cardiovascular health. It reduces the workload on the main heart, promotes healthy veins by preventing blood from pooling, and significantly lowers the risk of conditions like varicose veins, leg swelling (edema), and blood clots (DVT). Studies have even linked weaker calf muscles to poorer heart performance and reduced circulation efficiency. Specialists recommend frequent movement and exercises like walking and calf raises to keep this "second heart" strong and active.
