Run races, climb mountains, bike trails, ski slopes, and more with Smartwool’s adventure friendly PhD® line! Ideal for highly active individuals and a multitude of activities, Smartwool PhD® gives you performance in the highest degree! With socks, apparel, and accessories made of Merino wool, you can stay comfortable while you’re out there, no matter the weather.

Smartwool prides itself on making the most comfortable outdoor clothing with the best fabrics and technology, which is why they use Merino wool as their key ingredient. Merino wool is not only soft, breathable, and antimicrobial, but it will also keep you dry in the summer and warm in the winter, so you can wear or layer their pieces year-round!

The Smartwool PhD® line is made up of high-performing products with a Merino wool blend that are just as versatile as they are comfortable. Delivering on performance, comfort, and fit, you won’t need to look anywhere else!

Smartwool PhD®: Fabric and Technology

  • PhD® Ultra Light is ideal for high-energy activities in warm weather. Each product offers maximum breathability (a must in warm weather). The Merino and polyester blend is quick-drying, with better stretch, recovery, and shape retention for when you really get sweaty.
  • PhD® Light is ideal for high-energy activities in cooler weather. Featuring enhanced stretch and recovery, better shape retention and a faster dry time, PhD light also offers superior moisture management for cooler weather. Perfect for layering when the temperature drops even more.
  • PhD® is ideal for high-energy activities in cold weather. Featuring Merino against the skin and a nylon/elastane blend, PhD offers added warmth and abrasion resistance to keep you warm and protected while you’re out there.      

Smartwool PhD®: Gender-Specific Features

Using thermoregulation data from a 2011 study, Smartwool reengineered its socks and base layers to include high-tech, gender-specific features. In the study, they found that women run warmer than they perceive, and sweat in many different spots than men, so they used this data to make smart design decisions, like where to put breathable mesh zones in socks and how to build more warmth into areas of apparel where women need it most.

PhD Run socks for women hit the market in Spring 2015, the first Smartwool product line to be overhauled with this improved understanding of how women warm-up and sweat differently than men.    

Every Smartwool item incorporates findings from the study, but the PhD line offers the highest degree of performance for long days outside, no matter the weather. Check out some of our favorite Smartwool PhD products!       

Smartwool PhD®: Socks and Apparel   

Smartwool Women’s PhD Outdoor Approach Light Crew Socks (and Men) - $24.95

The next evolution in Smartwool's partnership with iconic alpinist, Conrad Anker, the PhD Outdoor Approach Socks takes sock technology to new heights. Designed to fit seamlessly in approach or hike footwear, these socks offer Smartwool's 4 Degree fit comfort and Indestructawool technology to handle demanding approaches, day hikes, and everyday wear.

Also available in Women’s Mini Crew and Men’s Mini Crew.

Smartwool Men’s PhD Run Ultra Light Pattern Low Cut Socks (and Women) - $15.95

Smartwool put all of their smarts into these new and improved run socks that feature Smartwool's 4 Degree elite fit system, Indestructawool technology for superior durability and a virtually seamless toe. Men’s-specific mesh ventilation zones provide ultimate temperature and moisture regulation where male runners need it most. A low cut height provides that ideal balance of protection and style.

Smartwool Women’s PhD Run Light Micro Socks (and Men) - $17.95

Smartwool's best fitting, most advanced run socks yet, Smartwool packed years of testing, prototypes and running smarts into these socks. Featuring Light Elite cushioning in the ball and heel of the foot for ultimate shock absorption with minimal in-shoe volume, women's-specific mesh ventilation zones, and a virtually seamless toe.

Smartwool Women’s PhD Cycle Ultra Light Low Cut Socks (and Men) - $15.95

When you’re 10 miles short of a century, the last thing you should be thinking about is your feet. Unless you’re wearing this cycling sock, in which case you’re probably thinking about how comfortable your feet are. Here’s why: Merino helps wick moisture and regulate body temperature, the 4 Degree elite fit system delivers a dialed fit and the Virtually Seamless toe protects against abrasion. Now featuring Indestructawool technology for ultimate durability.   

Smartwool Men’s PhD Light Long Sleeve (and Women) - $85.00

Welcome to your new favorite cool-weather shirt. It comes with head-out-the-door motivation build right in. Smartwool's PhD Light Long Sleeve uses a warmer Merino-polyester blend that’s expert at moving moisture away from your body quickly while you’re working out. When you’re done, hang it up and it will dry quickly. Designed specifically for men, mesh panels target male sweat patterns for great breathability. Merrow seam construction ensures a gentle feel and long-haul durability.

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