@himanshu-sharma Hello,If you stand all day and don't move around much, blood will tend to accumulate in the lower extremities, distending the walls of the blood vessels and allowing leakage of fluid into the tissues of the lower extremities. Muscle action like walking, running, etc is required. It Helps to move blood up from the legs and aids the heart in doing its job. It will improve blood circulation. Movement is a simple remedy.. The reason your calves go down during the night is because when you are lying down, level with the heart, it makes the heart's job of pumping blood, much easier because the heart doesn't have to pump against gravity and can move the blood/fluids more efficiently and that way can decongest the lower extremities more effectively.