Gear Review: Swiftwick Aspire Zero Socks

My feet are finicky.

No, seriously: I have some serious issues when it comes to footwear. I think it's partially due to working in the running business: I'm almost hyper-aware of anything when it comes to things that go on board.

This is particularly true with socks. I've had very limited success with most running socks. Whether it's a tighter or looser fitting brand, or an acrylic versus merino wool sock, or single-layer to double-layer variety, it's been an issue to be comfortable. I'd pretty much relegated myself to the fact that no matter what I have on my feet, I'll probably have a blister somewhere while running.

And that brings us to Swiftwick socks, and my experience with them.

The TechnoBabble
Swiftwick is an interesting company in the performance apparel industry. By that, I mean that 100% of the work for their products is done in the United States. To wit, they put it pretty bluntly on their website:

We decided to make all our products in the USA. Not some. Not most. All.

If you are a proponent of "Buying Local" or "Buying in the US," well, I'd argue you can't do much better than that.

Swiftwick's socks feature 200 needle stitching. What does that mean? Well, it's the highest density that you can get into a performance sock. This gives you an extremely tight-woven pattern to the sock. This, Swiftwick claims, will prevent debris from penetrating through the sock layer and creating a friction point that could, coupled with moisture, cause a blister.

This stitching also gives an extremely tight, almost second-skin feeling to their socks. The closer something is to the body, the better job it can do at moving moisture away. But also, this will prevent the sock from potentially bunching and generating friction in that manner. Less friction and less moisture means less blistering for feet.

Swiftwick uses both acrylics and merino wool for their socks. Acrylic socks feature, generally, a 75% to 25% ratio of water soluble and water proof materials. This allows the sock to gather moisture off of your foot, and then expel it into the moisture-management system of your shoe. Acrylics also provide the elasticity to wrap the foot well and create seams that you can barely feel. Merino wool, on the other hand, is a natural thermal regulator, attempting to keep your body temperature constant. Merino is also naturally anti-microbial (less bacteria, less stink!), and can move moisture while it's still a vapor.

Swiftwick has an extremely extensive product line. Your personal preference on material thickness and tightness will determine which of their line you would prefer. The Aspire tested here is their tightest fitting and thinnest sock; the Vibe is slightly thicker and looser (and far more colorful); the Pursuit is their merino wool product line; and the Performance is their original sock. Swiftwick also manufactures custom compression lines with their Vision product line. (Yes, this is the brand with the awesome argyle compression socks.)

Each product line also has a couple of different heights to the sock, denoted as Zero, One, Two, Four, Seven, and Twelve (referring to the length of the sock above the ankle). The Zero here is the lowest sock of the line.

Swiftwick Aspire Zero (image courtesy of Swiftwick)

The Run: How do they work?
How can I put this without it seeming a little, well, over-the-top...

They're, simply put, amazing.


The first thing you notice when you receive a pair of Swiftwick's is how small they look. I took a look at the sock, and then my foot, and went: uh-oh, did I get the wrong size? Fear not. There's so much elasticity to the sock that it gets on quite well.

Once you get the sock on, it's immediately noticeable how that 200 needle stitching worked out. These are extremely plush, wrapping the foot in a pillowy-soft material. Generally, this would lead to a pretty loose-fitting sock on the foot. But instead, these sit exactly true and contour to your foot. There's no gaps of material between your foot and the sock; it just seats true.

Out on the run, it's more of the same. The elasticity of the sock still allows your foot to properly splay out, unlike some other tighter-fitting sock vendors. There's a plushness that eliminates any seaming issue from the interior of the shoe; it makes up for a deficient interior of a shoe. Shoes that I have traditionally always blistered in? Nothing with the Swiftwick's.

The true test? This is the sock I ran Boston in. I ran in a pair of shoes that, traditionally, I'd always get a blister just forward of the arch on my left foot, especially if there was some extra moisture involved. Well, there was PLENTY of extra water kicking around, given the approximate 8 gallons of water that I dumped over my head during the course of getting from Hopkinton to Boston.

When I got to Copley Square and meet up with my family post-race, I kicked off my shoes and socks to get ready for my favorite post-race shoe: Birkenstock Arizonas. I had figured that, with the amount of pain in my legs, that I'd simply ignored any issues with my feet. After all, with that much water, something had to have been wrong with a blister, or something.

I inspected my feet closely, and was absolutely astounded:

No blisters. Not one. NOTHING.

Whoa.

The only tip from a purchasing standpoint: just ensure that whatever height you purchase will come above the heel collar of the shoe. This wasn't a problem with my Aspire Zeros and the particular pair of shoes that I ran Boston in, but it could be depending on your shoe. I'll be keeping a mix of Zeros, Ones, and Twos kicking around, just to make sure I have a pair that can be worn with any of my running shoes.

All my other run socks? Relegated to work sock status. I'm never going back. Well done, Swiftwick.