Compression socks are a type of hosiery that give extra support and better blood circulation to the people who wear them. They are sometimes called support socks, but should not be confused with athletic socks or diabetic socks (which do provide health benefits, but do not always work the same way).
Compression socks are specially designed so that the pressure on the foot and the leg beneath the knee is graduated. Why is that so helpful? Other socks can constrict the limbs, so that when the body pumps blood, the gravity “traps” some of the blood in the feet. These can lead to edema or swelling and other circulatory problems such as thrombosis and phlebitis. Even those who don’t develop medical conditions will experience discomfort. They can get cramps or suffer from fatigue. They may try to raise their legs to get the blood going again, and this may help a bit with the pain, but the relief is temporary. Once they walk around again, the discomfort returns.
Compression socks avoid the problem by using a strong material like spandex or lycra that add pressure to the legs, feet and ankles. Why would adding pressure solve pressure? Because it compresses the veins, forcing the blood to return to the hart instead of being trapped in the feet. Some brands of compression socks also provide additional support on the soles of the feet, improving the shock absorption.
Compression socks were once popular only among those who suffered from circulatory problems, but they are now entering the mainstream. Many travellers use compression socks on long flights in order to avoid leg cramps. Athletes also use them as a form of additional support especially when the sport involves a lot of jumping or running.