Skeletal muscles contribute to blood flow by its contraction.
Coordinated, rhythmical contractions during the exercise or some physical work enhance blood flow by the skeletal muscle pump mechanism. The muscle pump system refers to peripheral vessels, usually in the legs and arms, that have one-way valves which direct flow away from the limb and toward the heart. Those vessels compress as the muscles surrounding them contract, and they become decompressed as the muscles relax. Therefore, contraction and relaxation, make the vessels compress and decompress ( "pump").