Sorting the Socks
The most visible difference between all socks, athletic or dress, is the length. However, it is a mostly aesthetic choice. If you have diabetes or some other condition that requires clothing to encourage circulation, knee-length socks may be necessary (see Medical Socks for more information).
There are two main athletic activities in which a certain length of sport sock is appropriate: when wearing some sort of shin guard, and when running. The when worn with shin guards, knee-length socks are typically required so that they double up, over the guards. While running in the winter, knee-length socks can warm the legs as a substitute for running tights. In the summer, low-cut, anklet, or quarter crew socks are best for avoiding excess material around the legs. Apart from these two circumstances, the real difference among athletic socks is the material.
The two traditional materials for socks are cotton and wool. However, both kinds of athletic sock materials pose problems for athletes.
Cotton socks are inexpensive, but can lose shape quickly. Moreover, the fabric can absorb a disproportionate amount of water. This is bad for sports, since sweat from your foot will collect in your cotton socks. Your feet will also be emitting heat. The combination of water and heat creates the perfect environment for blisters and fungus, so athletes should avoid 100% cotton socks.
Wool socks are useful for some cold situations; but, like cotton, they absorb water. Wool socks do however, retain the ability to insulate when wet, but this can lead to the undesirable hot-and-sweaty scenario. Both cotton and wool can become irritable.
To solve the problems presented when friction, heat, and sweat combine with typical fabrics like cotton and wool, athletic socks are often synthetic blends, combining two or more natural and artificial fibers.
Note: For a fiber to “wick,” it needs to repel water away from the skin, while allowing it to evaporate through the shoe. Thus, it needs to be “hydrophobic,” not “hydrophilic.” Hydrophobic fibers can increase the sweat they transfer through greater cross-sectional surface area.
Nylon is a polymer known for its durability and resistance. It is well-suited for socks that undergo lots of pulling and stretching. However, it absorbs a relatively large amount of water compared to other synthetics.
Polyester, like Nylon, is a cheap polymer that can withstand wear and tear. Polyester socks can handle a little more absorption than Nylon, and breathe better. Polyester is the well-known “DRI-Fit” material from Nike.
Acryllic is a warm, wool-like polymer. Acrylic socks can retain their elastic shape amidst pulling; plus they wick sweat away.
Polypropylene is a “super” waterproof fiber with extreme moisture-wicking abilities. Polypropylene socks are also terrifically warm; and sometimes used as inner sock liners.
Spandex is known for its extreme resistance to stretching, and often added to socks to help them keep their shape. Spandex is also known by the names Elastane or Lycra.
Olefin is a synthetic known by the name “Coolmax,” the defining ingredient of many sport socks. Coolmax is one of the best fibers at both repelling water and passing the water through itself to the outside of the sock.
In order to further retain the shape of the sock, reduce friction, or wick moisture, all of which are necessary to avoid blisters, many sock blends include minor amounts of these synthetics:
Polyamide is a type of nylon added to athletic socks for comfort.
Teflon is added to waterproof the sock without affecting breathability. It also resists friction.
Profilen is a key ingredient in DryMax socks. It has the lowest friction coefficient (used to calculate how much energy is absorbed through friction) of all these materials.
Gore-Tex is an expensive waterproof material, used primarily in boots that can also be used for very thick sport socks.
Kevlar, like Gore-Tex, is thick and expensive. A light and strong material most known for bullet-proof vests, it is especially suited for athletic socks that prevent abrasion to the leg.
X-Static is a fiber made from silver that is woven into socks. Its anti-microbial nature helps sport socks prevent odors and fungus.
To get a better understanding of the sock requirements for specific sports go to the Socks by Sport section!