For those of you that have read CtB for a year now (wow, it's been that long? Seriously?), you probably have caught onto the indisputable fact that I'm a pretty opinionated guy. I hold a lot of things near and dear to my heart, and I won't let go of them, and I let them bleed through into my writing style.
However, my objectivity as a footwear fitter is another matter entirely; everybody has different running mechanics, different cushioning preferences, and different physiological factors that will only permit them to run in X way with Y shoe. (See, e.g., my What is Natural Running? post.)
Some would argue that, based on that positing and talking about how injuries have increased since the wave of natural running has started, that I'm ferociously against barefoot running.
Wrong.
Let me be clear, here: every runner should incorporate some type of barefoot work into their running repertoire. It's invaluable as a technique training tool, and to help build the mind-body connection that helps to reduce injuries later down the road; being able to recognize the difference between "sore" and "hurt" and "injured" is the only way you continue running for years upon years without interruption.
It is a matter of how much, and on what surfaces, you will be able to do barefoot work. I, for example, can do one short, slow run per week in my Five Fingers lasting no more than 40 minutes. I also then use them during the course of my strength training, and also wear them casually. How did I learn my limit? Via a stress fracture in my right foot when I tried to go for a second run a week in them.
But every body is different. Hell, Abebe Bikila won the Olympics barefoot. And it is for him that Vibram named their road running line after.
The Backstory
Vibram is not a footwear company by trade. Well, they are a footwear company in that they have made soles for shoes since 1934. But the FiveFingers line-up was their first foray into the actual full-scale production of a shoe from the ground up.
FiveFingers were originally introduced in 2005, following a six-year development process. (Remember last week's posting on the Wave Rider 15, and the bit on lead time? Well, just goes to show how long it takes to get something right...) The original line-up of the Classic, Sprint, KSO, and Flow were all developed for the outdoor world: rubber outsoles similar to boat shoes, no cushioning, machine washable, extremely flexible. They were perfect for camping, hiking, fjording the river on the Oregon Trail (watch out for the dysentery), and in casual environments.
Then two events took place that took the running world by storm.
First, Ted MacDonald (aka Barefoot Ted) began advocating for the use of FiveFingers as running shoes. Ted has made a wonderful career out of coaching barefoot technique, and smartly saw the potential for FiveFingers to grow.
The second, of course, is Born to Run. Forget about whether you think Chris McDougall is a certified nutjob, patron saint, or anything in between. It is undeniable that his book took off, and FiveFingers were along for the ride.
Although sales had exploded, Vibram also understood that there was going to be a need for a little bit more shoe for under people's feet on the road. After all, asphalt isn't exactly the surface that the human body is designed for. And with that, along came the Bikila.
The TechnoBabble
The Bikila features 3 millimeters of ethylene vinyl acetate (EVA) throughout the course of the midsole. EVA is the same material that almost every running shoe manufacturer utilizes today (with the grand exception of Ecco). To put the amount of cushioning in perspective, the Saucony Kinvara (a shoe that attempts to put you into a similar body positioning as being barefoot) features 19 millimeters of EVA. So we're talking over 6 times less cushioning, which, of course, is the point.
The outsole on the FiveFingers is a mixture of carbon and blown rubber. Carbon rubber is the more durable of the two materials, whereas blown rubber is carbon rubber with more air in the mixture. This helps give the shoe durability, while also making sure that it remains light. The outsole pattern looks a lot like the pattern from the old Brooks Ghost outsole, which is a good thing: it lasted, and that's what we're looking for in a shoe that doesn't really ever lose it's cushioning value.
Much like all FiveFingers, the Bikila's are machine washable. Air dry them, unless you care to ruin your dryer. The upper on these is synthetic, but does not feature a mesh like the KSO's. This proves pivotal a bit later on.
According to the scale, a size 42 (a rough translation for a size 9 foot, which is what most published men's shoe weights are) will tip the scales at 6 ounces.
The Run
First off: these are firm. Duh.
That being said, having run in both the KSO and the Bikila, I can tell you that the cushioning makes a huge difference on firmer surfaces. Concrete still sucks something terrible, but asphalt is tamed to a fair degree. You definitely want to be light on your foot, and paying attention to what your body is telling you.
One of the bigger changes overall here is the flexibility in the outsole. Because it has all of these different pieces connected to a midsole, rather than the midsole and outsole being one and the same, you do lose some of the flexibility from the original models. This isn't necessarily a bad thing. Think of why we build houses on concrete foundations: because they are firm. It helps give the foot a stable basis to stand on top of. In that spectrum, then, the Bikila is a slightly more stable platform compared to its' fellow FiveFingers.
The choice in upper material is equally compelling and infuriating. The compelling aspect of it is that it is slicker, and results in an interior that does not blister at the same rate as KSO's. It is infuriating because it is not elastic, and it is hot as hell. The lack of elasticity, coupled with a low strap, means that anybody with a higher in-step will not be able to wear this model. Instead, you'll be hunting out the Bikila LS, with the separate tongue and draw-style enclosure.
Overall, be careful with those first few strides. Don't be overzealous. Listen to your body. It will tell you what you're doing wrong. It'll also tell you if you're being too ambitious. It will give you the tools to know whether the amount of cushioning here is something that you prefer, or the body positioning is best for you. From there, perhaps you'll be a VFF wearer for all of your runs. Or perhaps not. And either is fine.
At the end of the day, the Bikila is a solid barefooting option that allows a foot that fits into it to run more surfaces in a barefoot-esque shoe. Whether that means it is a supplemental training tool, or your everyday runner, is up to you to find out.