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The Smartwool PhD Run Light Elite Micro was one of the highest scoring running socks in our review. It is unique for its use of Merino wool as the main component of the fiber blend, rather than some form of polyester like the majority of socks we tested. It is a very light sock that uses minimal amounts of targeted cushioning only in the areas of most need in order to protect the foot in an optimal way for running while still staying light and cool. The merino wool is used in the padded areas and does a great job gripping the foot, wicking away moisture from the inside, and is supremely comfortable against the skin. This sock has a nearly perfect design for a running sock, and is hard to beat. Its only downside is the price, which is to be expected considering the liberal use of natural fibers. As one of the highest scoring socks in this review, the Run Light Elite Micro is one that we wholeheartedly recommend.
REASONS TO BUY
Perfect amount of padding
Does a great job of wicking away moisture
REASONS TO AVOID
A bit on the expensive side
Very wide size range for a single sock
Looking for a different length?
If you're looking to add some different lengths to your sock quiver, have no fear: SmartWool has tons of options. From the short PhD Run Ultra Light Low Cut Socks for $16 and the PhD Run Light Elite Mini Socks for $18, to the longer PhD Run Ultra Light Mid Crew Socks for $19 and the fun PhD Run Light Elite Pattern Crew Socks for $22.
Our Analysis and Test Results
With its very light and breathable nylon and elastane fabric blend around the arch and top of the foot combined with fluffy and comfortable targeted padding, this sock if very reminiscent of the Thorlo Experia XCCU. While it was the third highest scoring sock when comparing all of our testing metrics, we found that it was slightly tighter for us in a couple areas, ever so slightly compromising fit and comfort compared to the Thorlo. For someone with a foot size that fits right in the sweet spot of the size range (9-11.5), this may indeed end up being the perfect fitting sock, but for us it was a bit small and needed to be stretched tight over the foot.
The only other area where it suffered compared to the competition was slip prevention. Although it did a great job of securely hugging our foot, we found that this one slipped inside a loose shoe a bit more than some others. As a low cut, which translates into “no-show tab,” this sock can only be worn with low topped running shoes, unless one wants to deal with the sock slipping back into the shoe. For those with other kinds of shoes in mind, a higher ankle cut is recommended.
Performance Comparison
Courthouse Mountain and Chimney Rock in the background on a “testing” run up the West Fork of the Cimarron River in the San Juan Mountains of Colorado. While no-show socks will work for this sort of terrain, they are not ideal, as they tend to more easily collect mud, dirt, and debris.
Comfort
The Run Light Elite Micro is a very comfortable sock, especially the texture of the merino wool and nylon fibers against the skin. The nylon is blended with elastane in a double crossing pattern across the tops of the feet in order the securely hug the midfoot. The wool fiber pads do a great job of covering the parts of the foot that need the extra cushioning, especially the forefoot, toes, and sides of the forefoot, as well as the heel. Our only complaint was that for our foot the sock felt a bit tight, especially across the top of the foot and the front of the ankle. It was not as egregiously tight as the Feetures! Elite Light Cushion No Show Tab, but was not as supportive without tightness as the Darn Tough Coolmax Vertex Tab No Show Ultra-light Cushion. Our minor complaints regarding comfort would perhaps disappear if you have a foot size in the middle of the size range, around 10-10.5. 8 out of 10 points.
We experienced the slightest bit of constriction in the front of the ankle with this sock, but it was a minor complaint. Side view of the wicking cushioning vs. the breathable nylon parts of the sock.
Fit
For our size 11 feet we ordered a size large sock, which has a size range of 9-11.5. We wish that this range was a bit smaller and more targeted, ala the Thorlo Experia XCCU, because for us the fit was just a hair tight. Although the nylon and elastane fabric across the arch and top of the foot did a great job of stretching to accommodate our feet, this sock certainly felt snug. That said, the only constriction we felt was at the front of the ankle, like we mentioned above, and the amount of tightness felt at that spot was minor. While Smartwool calls this a “low” cut, we felt like it was exactly comparable to the other no-show socks in this review, meaning it ended below the ankle bones. It does have a padded tab on the back of the ankle designed to keep the sock from slipping off the heel and down into the shoe, and this works just fine as long as you are not wearing high top shoes. As it did not fit quite as well as the best socks in this review, we gave it a 7 out of 10 points for fit, the same as the Balega Hidden Comfort.
Showing the no-show height of these socks, resting just below the ankle bone. Notice also the tab in the back that helps protect the back of the ankle as well as keep the sock from slipping down inside the shoe.
Wicking
This sock performed up there with the best when it came to wicking moisture away from the foot, roughly the same as the Thorlo Experia XCCU, but not as good as the very unique DryMax Running Mini Crew, our Top Pick for Wicking. After the 15-minute on-the-foot test we found that there was quite a bit of moisture still present on the outside of the sock, but that the inside, especially the wool padded areas, were much dryer. This led us to conclude that the heat from our foot was indeed helping moisture to wick through the wool fibers of this sock. In the one-hour drying test, our findings were validated. The wool pads on the inside of the sock were once again the driest parts, showing that they didn't absorb as much moisture as the nylon fibers, and also dried out faster. We gave this sock 8 out of 10 points for wicking, and think that it is a great choice for runners who often run in wet or rainy conditions.
With water abundant and no bridges in sight, the wicking ability of these socks is going to surely be tested in the Uncompahgre Wilderness, Colorado.
Padding
Not only did Smartwool deliver on its promise of “light elite cushion,” but also produced what we think is the perfect combination of light thickness combined with comfortable padding in only the most necessary areas. The merino wool pads effectively cover all the areas of potential rubbing and abrasion, including the tops of the toes and the sides of the forefoot, an often overlooked area that can really use some extra attention on longer runs. Along with the Thorlo Experia XCCU, and slightly better than the Darn Tough Coolmax Vertex, which included padding underneath the arch, this sock did the best out of any in our test at delivering exactly what was promised with padding in a way that makes the most sense for running, and for that we gave it 9 out of 10 points.
The inside of the Smartwool sock shoes the black merino wool pads and the white nylon and elastic stretchy bands that loop over the top of the foot and the arch.
Slip Prevention
Slip prevention was the only area where the Run Light Elite Micro did not absolutely shine. We found while running in it both up and down steep hills in loose shoes that while it did a fantastic job of gripping our foot, the slicker wool outside of the sock was more prone to moving around in a shoe than some of its counterparts. It performed roughly the same as the Balega Hidden Comfort, a sock that we found to be pretty slippery in general, but it was still a bit better than the only other merino wool sock in this test, the Darn Tough No Show Light. While some have complained online about the back of the sock easily slipping off the heel, we did not experience that problem in this very snug sock. Where your foot falls in the size range may play a role in how snug this sock feels, however. 5 out of 10 points.
The black fibers are looped padding over the heel made of merino wool. Notice how they come all the way up to where they join with the heel tab, completely padding the Achilles region on the heel.
Best Applications
As a very thin and light sock with padding targeted in all of the appropriate areas for running, this sock is a fantastic choice for hitting either the roads or the trails. Due to its no show height, it may not work as well as a mini crew sock for trail running, and we wouldn't use it in shoes taller than ankle height. Try finding it in a slightly taller ankle cut if you still want a great sock with slightly more versatility.
Value
This sock retails for $18.95, making it the most expensive pair of socks in our review. The fact that it is made of imported merino wool yarn is likely the main culprit for this elevated price, and we feel that it performs up to its price. While you can surely find really great running socks that are cheaper, we find it hard to imagine that people would not be happy with this sock, even for the slightly higher cost.
We loved how the black padding completely covered all the areas in the forefoot that potentially rub, including the sides of the forefoot and toes. Also visible here is the criss-crossed elastic support over the top of the foot.
Conclusion
The Smartwool PhD Run Light Elite Micro is a fantastically designed sock that delivers exactly what is needed for running without anything extra. It is one of only two socks in this review made mostly of merino wool, and does a great job of blending support and comfort with great wicking ability. As the third highest scorer in this review, it is a sock that we think almost any runner would be happy with, and also makes a great choice for runners in wet climates.
Other Versions
Men's PhD Run Light Elite Low Cut
Cost: $17.95
Low cut socks come up higher than the micro, just barely covering the ankle
Men's PhD Run Light Elite Mini
Cost: $17.95
Mini crew height easily covers the ankle
Men's PhD Run Ultra Light Micro
Cost: $15.95
No padding whatsoever, the lightest running sock Smartwool makes
