Anyone shopping for athletic socks these days may be overwhelmed at the staggering number of choices boasting the latest technology and fibers with names such as Coolmax, Thermax, ClimaLite, Thorlon and on and on.
Today, there are socks for running, golfing, hunting and snowboarding - one can even purchase a $250 "exercise walking system" consisting of sock, shoe and shoe-liner sold together.
Sales of sports socks are robust, with "premium sports hosiery" representing, conservatively, 50 percent to 60 percent of the $1.8 billion sock industry, estimates Mike May, spokesman for the Sporting Goods Manufacturers Association.
With so many choices, pity the poor shopper who yearns to fall back on mom's stock advice: "Buy cotton. Cotton breathes." Nowadays, it's more complicated than that.
Here, to help, are some sock-picking pointers.
For starters, researchers have found that - contrary to mom's advice - you are better off with socks made from synthetic fibers and blends, for most activities.
And the cotton-versus-synthetic conundrum is just the beginning. Choices include fibers engineered and blended to keep your foot warm or cool; to hug your arches or ankles; to protect your foot from a pounding or to slide in your shoe like a stocking.
These features may not matter when it comes to puttering around the house, but they can make a big difference when it comes to staying dry, comfortable and blister-free while exercising.
"It's a common misconception that socks are not important," says Dr. Douglas Richie, a podiatrist in Seal Beach, Calif., who is a recognized expert in sports socks and has researched, among other things, the effects of cotton and acrylic fibers on feet.
"They are the most intimate layer of material against your skin," Richie says. "When people get calluses and blisters they first blame the shoe, when they should be looking at the sock."
High-performance socks are designed to control two forces that affect a foot in motion: impact (the downward, percussive motion of the foot as it hits the ground) and shear (the force created when the foot slides forward and backward, and side to side, in the shoe). Impact and shear work together and separately to cause blisters, calluses and foot pain.
Socks can dissipate impact and shear with judiciously placed padding - the thicker the sock, the greater the protection.
But the most important thing a well-designed sock can do is dispense with the foot's biggest enemy - moisture, which greatly increases the chances of contracting blisters, fungus and athlete's foot - even warts.
The key is to draw - or "wick" - sweat away from the surface of the foot toward the inner surface of the shoe. The most effective way to do this is with certain fibers.
Fibers generally fall into two categories: absorbent, such as cotton and wool, and water repellent, such as polyester and acrylic. In theory, fibers that repel water keep the foot drier by channeling moisture away from the foot. Fibers that retain water leave moisture next to the skin. Hence the popularity of synthetic fibers such as Coolmax, a fiber that is commonly used in high-performance socks.
In addition to incorporating advanced fiber technology, manufacturers are mixing fibers strategically, to accentuate wicking action. For example, today's high-performance sock may have a wicking fiber against the foot and an absorbent fiber, such as cotton or wool, on the outside of the sock to suck the moisture away from the skin.
Ideally, a good sports shoe will complete the circuit, wicking moisture to the surface of the shoe, where - if the shoe, as well as the sock, is well-chosen - it can exit the shoe altogether.
To fully avoid moisture issues, however, Richie recommends wearing very thick socks, even if it means going up a shoe size. A thick sock will wick moisture away from the inner surface of the sock to the outer surface of the sock, where it will stay.
Sales of socks geared to specific sports and activities - the "sports-specific" sock market - is growing, says Jim Throneburg, chairman and owner of Thorlo Inc., which pioneered this concept.
In his nearly three decades at Thorlo, Throneburg has seen the company product line grow from a few sock styles to 77, in 32 "families" of socks - for golfing, snowboarding, tennis, mountaineering and more.
But all of this technology comes at a price. Many brands of premium sport socks will run as much as $10 or more a pair.
Richie believes that they are worth it, especially for growing feet: "Children put out high volumes of moisture even when they're not running," he said.
"Any active person needs to look at socks as an essential piece of equipment," he said.
Janet Cromley writes for the Los Angeles Times.