By Tom Demerly.
Like all equipment geeks I’m rarely happy with the way something comes out of the box. I am always tweaking and tuning. Shoes are no exception: Different insoles, laces, lacing patterns, even grinding the outsoles to get a different “feel” or extract some elusive measure of performance. K-Swiss has acknowledged the opportunity to tune running shoes with their internal components in the new miSOUL Tech feature in their Run One-miSOUL Tech convertible running shoe.
What’s convertible? The K-Swiss miSOUL technology features a modular, interchangeable insole system (miSOUL) that can be exchanged to tune the feel- and maybe performance- of the shoe. This capability effectively makes the Run One more than one shoe. K-Swiss also has a miSOUL court shoe with similar interchangeable sole miSOUL technology.
“Just how much tuning can changing the insole do?”
The first thing I thought of when I heard of the K-Swiss Run One-miSOUL Tech (besides the name being too long) was, “Just how much tuning can changing the insole do?” K-Swiss marketing of the Run One-miSOUL Tech suggests it is one shoe that spans a spectrum of racing shoes and long distance training shoes. K-Swiss has also hinted about the development of an aftermarket additional insole for recovery.
Can one shoe be this versatile simply by changing the insole?
The insoles in the K-Swiss Run One-miSOUL are more than simple insoles. They are as elaborate as the name of the shoe. The 61 gram “Light 1.0” insole wraps significantly up the lateral and medial heel and includes five different materials for cushion and stability. This is the performance oriented midsole intended for tempo training and race day. The “Cushion 1.0” is heavier at 82 grams, shares the same concave wrap and integrates Si-18 shock-absorptive gel with a stiff thermo-polymer arch laminated into the insole for additional stability and support. Each insole has a synthetic fabric inner that is sublimated with the K-Swiss logo. Both pairs of insoles are included in the box with the purchase of the shoes.
The interchangeable insoles co-locate within the shoe using a pin and hole alignment that precisely places the insole inside the footbed. It does not insure the sides of heel are wrinkle free and you need to double check that when you switch soles. The sides of the heel cup are thin and can wrinkle if you switch insoles too quickly.
The interchangeable insoles aren’t the only interesting feature/benefit set on the shoe. From the front of the shoe the toe box is perforated with ventilation holes that K-Swiss calls “Flow-Cool System”. These holes will also facilitate drainage when you dump an aid station cup over your head. The saddle and tongue area are conventional in configuration and performance with a good, tunable fit via the 14 eyelets in the upper. I’ll suggest these shoes are absolutely sock-less friendly for race day.
The heel counter includes a molded polymer material heel cup with perforations and a faux-carbon spar that stiffens up the heel counter. K-Swiss mimicked an air cushion system in appearance with two windows of firm polymer that provides roll control in the heel. As a result of these heel features the shoe has a very “guided” ride with either insole set. Additional stiffeners span the midsole adding stability and lateral roll control.
Forefoot flexibility is great since the midsole transitions to more flexible foam up front skinned in Aosta II wear resistant rubber in contact with the road. There is the traditional higher density wedge on the medial insole to prevent pronation.
At 12.3 ounces in a size 9.5 the shoe isn’t a lightweight, but there is a lot going on there in 12 ounces. The 12.3 ounce weight is with the heavier 82 gram cushion insole.
The shoe geometry includes a 32.5 mm high heel and a 20.1 mm forefoot at the metatarsal for a drop of 12.4 mm from heel to toe. This is not a minimal shoe. For this tester that is good as minimal shoes haven’t been able to keep me on the road without aches and pains. I like the geometry of the K-Swiss Run One-miSOUL.
Fit on the K-Swiss Run One-miSOUL is true in length and roomy in the toe box with both insoles.
So- how much difference does changing the insoles make? The obvious test is to put one insole in one shoe and the other insole in the other shoe and take them for a spin or two. I had the strong notion that the Light 1.0 insole rode lower in the heel. As a result I stuck to the Cushion 1.0 insole and probably would even for racing in this shoe. The difference is noticeable, but insoles alone- even nice ones like these K-Swiss, don’t make a trainer a racer. This is a substantial shoe and will remain such- and I don’t mind that at all.
Having run in both insole configurations: There is a difference. Is it the difference between a racing shoe and a training shoe? No. Is the difference tangible? Yes. Does this one shoe replace multiple pairs of shoes? Probably, but ultra light racing shoes is not one of them. This shoe does not magically become a pair of K-Swiss’ excellent Blade Light Run racing shoes. That said the shoe does do double duty as more than one pair of shoes if you are going to actually swap out the insoles. I’ll suggest the real world tendency may to do what I did and simply pick the one you think feels best and stick with it.
Overall the handling of the shoe- the way it goes onto and come off the ground at speed- is great. I’d run and race in these. It is apparent K-Swiss is listening to their athletes on fit, design and geometry by the way these shoes feel. No extraneous twisting and good ride quality. This is a solid Ironman shoe since it has good drainage features and is substantial enough to support tired, swollen, aching feet during that last, awful 10 miles of the Ironman Marathon.
K-Swiss has been ambitious about their running program from the start and have scored a couple major coups including their excellent Blade Light Run shoes. I’ll suggest the K-Swiss Run One-miSOUL Tech is a continuation of that ambition. While it doesn’t do everything you need in a running shoe- or claim to, it does have substantial versatility and the option to tune to your preference of insoles right out of the box. I put this shoe down as an interesting interpretation of a full-featured trainer and a supportive racer at long distance that comes with two insoles out of the box. If you do the math on a pair of nice trainers and an aftermarket pair of insoles the $124.95 price tag continues the K-Swiss legacy of a lot of technology at a good value price. I like the ride, fit and features of the K-Swiss Run One-miSOUL Tech and look forward to some great miles in these.