OS1st Performance Socks

GEAR REVIEW – OS1st Performance Socks

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My distance running and the copious miles leading up to an effort take a beating on my socks. I’ve spent decades with foot issues and found that a lot of them revolve around failing to choose the right sock for the right activity. 

I’ve tried every fad sock out there, from toe socks to crew vs. non-crew to compression style socks. It turns out, my preferences shift from road running to trail running to mountain running AND that is ok. 

Recently, I was presented the opportunity to test out OS1st socks. I’ve heard some mention of these socks in the sector of the ultra running community that’s not obsessed on over hyped toe socks (those serve a place too, but I’ve had horrible luck with durability). 

For purposes of this review, I received a pair of FS4+, FS4, and TA4 socks. For sizing, I am a Women’s size 10 shoe size (EU 42). Here is a run down on three socks I tested in the OS1st line-up and the conditions I found they excelled most:

FS4+ Compression Bracing Socks – Over the Calf ($49.99)

Product Tested: FS4+ Fusion Pink, Size M

I’m a sucker for loud colors, so admittedly I was over the moon that this sock was offered in neon pink. Thankfully, this sock didn’t stop at its good looks. I reviewed this sock 10 days after running a high altitude 100k with 28,000′ of elevation gain and loss. My legs were very much still in recovery mode when I slipped these on for a mountain run with 4,000′ elevation gain over 12-miles. Immediately after putting them on I could feel the compression do its job. My legs couldn’t have been happier. All residual swelling from my previous ultra run had disappeared after this recovery run wearing these socks.

Since that run, they have accompanied me for every big day in the mountains. I love the firm compression around my arch that makes my nagging Plantar Fasciitis seemingly disappear while wearing them. These run true to size, if not a tad large; however, once they are on there is ZERO slipping down my leg regardless of how many hours or days I wear them for. The reflective details are an incredible touch, as many of my runs extend through the night and I appreciate the extra visibility. As for durability, none of my toes popped through the socks and they survived a few washings so that’s a great sign. I’ve only had these for a month, so I can’t speak to their long term durability just yet.

Image courtesy of OS1st

Ideal Use: Long, strenuous efforts, recovery or jobs that require standing on your feet all day

FS4 Plantar Fasciitis Compression Socks ($24.99)

Product Tested: FS4 Merino Wool No Show Socks, Size M

Earlier this summer, I developed every runners nightmare – Plantar Fasciitis. It was essentially an issue I had developed after my arches flattened in pregnancy three years prior that was exacerbated by not using proper insoles in my running shoes. I had no idea a sock could support what I had been taping and obsessively rolling out with any hard object around my house. OS1st included 4-zones of varying compression on this sock (below for image). My absolute favorite zoned compression is Zone #2, where I can feel my arch instantaneously supported as soon as I put these socks on. I’m blown away by how well the compression is zoned on this sock. I now skip the taping and wear these instead for a pain free running experience.

This sock is available in a no show, 1/4 crew and crew. I tend to only wear no-shows for road running and dreadmill sessions, but the 1/4 crew is a staple in my trail and mountain running quiver. Either way, the merino wool does an incredible job with wicking moisture away from my foot even on the dreadmill! I’m absolutely obsessed with this sock. As for durability, they seem to be holding up really well. 

Zone image
Image courtesy of OS1st.com

Ideal Use: Everyday trail running and multi-day adventures

TA4 Thin Air Performance Socks ($12.99)

Product Tested: TA4 Thin Air Performance Socks in Lavendar, Size M

I call this one the daily driver. This summer has been unseasonably hot in Colorado. As such, I’m a sweaty mess everywhere including my feet. There is no better time to have your footwear be light as a feather than a dry Colorado summer. I was originally very hesitant with this sock as it seemed pretty lack luster at first glance. Similar to the rest of the OS1st line up, this sock features zoned compression (image below). It is a very mild compression, but the sock functions as a second skin unlike many other socks I’ve tested of this type.

Where this sock really shines is its ability to stay put, which in turn reduces the opportunity for hot spots or blisters to develop. I learned to love the right thin sock for skimo racing, which has guided me into exploring this for running as well. True in all heat generating speed sports – skimo, running, etc., thin is the way to go when friction is the enemy. As for durability, I have taken this sock out for many opportunities to implode, but it’s still functioning and intact just as it was straight out of the packaging. For a road marathon distance or shorter, this is my sock of choice. 

This thin air, max air flow technology is also available in a compression calf sleeve, although was not tested by us. 

Ideal Use: Warm weather activities, daily driver speed demon.

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Raised in the ocean lined landscape of Southern California, Ilana now calls the rocky mountains of Colorado home. Ilana is a mother to an adventurous daughter, an accomplished rock and ice climber, skier, snowboarder, mountain distance runner, avid adventurer, and a Registered Trauma Nurse. A recent, near fatal accident in May, 2018, has left Ilana with a new disability; bringing her biggest life challenge to head, adapting to continue her pursuit of long, hard days in the mountains and share it with the generations to come. Ilana is the founder of Thrillseekers Anonymous, a seasoned event speaker, and has been featured in various media outlets including the February 2015 issue of ‘Climbing’ magazine, December 2013 issue of ‘Rock and Ice’ magazine, December/January 2013 issue of ‘Gripped Climbing’ magazine, Canyoneering: A Guide to Techniques for Wet and Dry Canyons (How To Climb Series) by Dave Black and Pasadena Magazine as well as a Climbing Expert on MTV’s Parental Control (Season 7 – “Heather”).

Ilana has written 123 articles for Thrillseekers Anonymous.

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