Vibram FiveFingers KSO Review

A review exploring the physical and emotional effects of the Vibram FiveFingers KSO.

By on May 19, 2010 | Comments

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Vibram FiveFingers KSO Review

Vibram logoI’ve always liked to feel the earth underfoot. As a kid, I stomped barefoot through puddles, especially the gooky ones, to feel mud squish up between my toes. I walked with no shoes in sand boxes so much when I was little that, the first time I met sand dunes as an adult, I ran around on them unshod until blisters stopped me in my tracks.

My penchant for sticking my toes into real, live earth wasn’t what first drew me to the Vibram FiveFingers KSO last year, though. Over the previous nine months, I had won a battle over plantar fasciitis through rest and physician-administered anti-inflammation treatments. Though my wound had healed, the weird strength imbalances in my hips and lower legs that caused the injury were still present. I was engaged in physical therapy to address those biomechanical deviations (and to further restore healthy plantar fascia tissue), but I had heard through the runner’s grapevine that FiveFingers walking and running might also help with my body’s rehabilitation by “forcing” perfect movement.

The first time I shoved my ten toes into those FiveFingers to do some chores around my house, I felt akin to a monkey. My toes spread out so much that I half expected my big toes to shift into a position of opposition against the rest of my toes. That evening, I did dishes, took the dog outside, folded laundry, and, in general, took a dainty approach to wearing this new kind of shoe. Though I didn’t awake the next day with opposable, tree-climbing toes, I did stand up to ten tired piggies! Without the confines of a shoe’s toe box, my toes splayed wide into positions little experienced since my childhood days of mud splooshing and sand romping. I gave the toes a few days of rest inside traditional shoes, then did it all again.

After several weeks, my toes felt strong enough to FiveFingers walk on my local rails-to-trails railroad bed trail. For about twenty minutes of walking with a few one-minute bouts of running, I felt the earth and all of its intricacies underfoot. Upon footfall, my toes curled around rounded river stones. I felt plugs of grass compact under my body weight. I felt my wide-lying toes become a stabilizing platform. This close contact with the ground appealed to what must have been my residual early hominid genes, because I felt wild, primitive, and playful!

Joshua Tree FiveFingers KSO

The author running in her KSOs in Joshua Tree NP. Photo by Leslie Gerein.

That is, until I woke up the next morning to distinct discomfort in my calves and hip muscles. Traditional running shoes purvey the opportunity to off-load the impact of movement on cushioned soles. FiveFingers and their thin rubber soles require your body to absorb almost all of movement’s impact. My calves and hips seared for a couple of days, so much that I had to take time off from my traditionally shod running routine. I held tight, returned to these same trail, distance, and pre-human-like meanderings once per week for the next few weeks, and hoped that the products of this pain would be stronger calves and hips, and a resulting, improved running form.

I would be remiss if I didn’t pitch in a few words of caution. Running around almost barefoot, unless you pretty much already live shoeless, should be approached with a degree of moderation unknown by most distance runners. The ability to ignore common sense and fatigue to run silly distances and terrain, the precise qualities that make us ultrarunners, will cause nasty injury with FiveFingers.

FiveFingers KSO cactus

Avoid kicking cacti in your KSOs. Photo by Leslie Gerein.

In short, do much, much, much less movement in them than you think you should. I can speak from experience, twice. After increasing my time running in FiveFingers too quickly, I experienced minor inflammation in one Achilles tendon because of overworked accompanying calf muscles. As I increased my time running in FiveFingers, I also got excited about trying to run faster in them. While running down a road at a pace too fast for me to modify my footfalls on the varying terrain, I stepped on rock and bruised the bottom of my big toe. The first incident precluded careful training modifications for about a week to recover, and the second one was an uncomfortable nuisance. I’ve, knock-on-wood, escaped my early FiveFingers use with little issue. And, I’ve learned my lesson!

I have a minor complaint about the construction of the Vibram FiveFingers KSO. The inside of the toe holders have significant amounts of rough edging from stitching fabric and rubber together. I’ve run only moderate distances in this model so, though I can feel the seams, I haven’t experienced any chafing. I do wonder, however, how those seams would perform during a long run.

At present, I remain an immense Vibram FiveFingers fan, and I now run about once per week for an hour in them. While I can’t say that my form is perfect, I know it to be improved because my plantar fasciitis hasn’t returned. I have faith that my calf and hip muscles have at least adapted to these improved biomechanics because they no longer get sore after these runs. Finally, I can also say that my weekly FiveFingers runs have re-impassioned my running with a reminder of why I do what I do out there. With the FiveFingers, I feel the wild earth as I press my toes into it, just like the mud puddle and sand box days of my childhood.

Call for Comments and Questions
We here at iRunFar would love to hear about your experience with Vibram FiveFinger KSOs, any other FiveFingers model, or barefoot running in general. As always, we’ll do our best to answer any questions you might have about the shoe.

iRunFar's Runner-in-Chief sporting Vibram FiveFingers KSOs in Canyonlands NP.

iRunFar’s Runner-in-Chief in Vibram FiveFingers KSOs.

Meghan Hicks

Meghan Hicks is the Editor-in-Chief of iRunFar. She’s been running since she was 13 years old, and writing and editing about the sport for around 15 years. She served as iRunFar’s Managing Editor from 2013 through mid-2023, when she stepped into the role of Editor-in-Chief. Aside from iRunFar, Meghan has worked in communications and education in several of America’s national parks, was a contributing editor for Trail Runner magazine, and served as a columnist at Marathon & Beyond. She’s the co-author of Where the Road Ends: A Guide to Trail Running with Bryon Powell. She won the 2013 Marathon des Sables, finished on the podium of the Hardrock 100 Mile in 2021, and has previously set fastest known times on the Nolan’s 14 mountain running route in 2016 and 2020. Based part-time in Moab, Utah and Silverton, Colorado, Meghan also enjoys reading, biking, backpacking, and watching sunsets.