Final answer:
The calf muscle pump, also known as the skeletal muscle pump, helps circulate blood back to the heart by contracting leg muscles which compress veins and push blood through one-way valves.
Step-by-step explanation:
The calf muscle pump, which is also known as the skeletal muscle pump, is a mechanism by which the contraction of the leg muscles assist in the circulation of blood back to the heart, especially from the lower extremities. As muscles like the gastrocnemius and soleus contract, they compress nearby veins and push blood through the one-way valves, preventing backflow and aiding in the return of blood against gravity. This prevents pooling of blood in the limbs, which can occur when standing still for long periods, potentially leading to fainting due to inadequate oxygenated blood reaching the brain.