Elevating the legs while sleeping is good for blood and venous and lymphatic reflux, while reducing the burden on the heart. When the body is standing or sitting for a long time, it is easy to cause poor venous or lymphatic return, resulting in pain, soreness, swelling and other symptoms in the lower limbs. Elevating the feet is good for the heart and lymphatic fluid return, and if necessary, a small pillow can be placed at the knee or popliteal fossa, which is more conducive to venous return. If the leg is swollen due to poor venous return, you can also take oral medication, which can eliminate the edema in the leg and can make the swollen area disappear completely.