By Chris MacLeod, Rogue Running Cedar Park

Here at Rogue, we have one surefire method for determining how much of a shoe geek someone is. It involves observing their reaction to this shoe:

Average runner: “Oh, that’s a different-looking shoe.”

Total shoe geek: “Oh wow, you guys carry Karhu???”

Karhu History

Karhu, Finnish for “bear”, is a Helsinki-based company that dates back to 1916. (Technically, the company name is “Karhu Sports”, not to be confused with Karhu beer, reportedly Finland’s most popular lager.)

Long before the rise of runners from East Africa and the Caribbean, the world of track and field was dominated by the “Flying Finns”. Karhus graced the feet of such famous runners as Paavo Numi and the Finnish team that accepted Steve Prefontaine’s invitation to race at Hayward Field in 1975.

Yes yes, this is supposed to be a shoe review, not a shoe history report. Just ONE more fun fact: It was actually Karhu that created the famous 3-stripe logo that now graces Adidas products. Karhu sold the mark to the then-small German company in 1951 for the equivalent of 1,600 Euros and two bottles of whiskey (the latter being equivalent to…two bottles of whiskey.)

Technology Overview

Here at Rogue, we carry four of Karhu’s road shoe offerings:

Clockwise from top-left: Flow3, Fluid3, Fast3, Steady4

These shoes run the range from very light neutral trainer to decently-cushioned stability shoe, but all four are built around Karhu’s patented “fulcrum technology”.

Don’t you wish you’d thought to patent the fulcrum?? Genius!

In running shoe terms, this means that the midsole includes a triangular-shaped wedge of higher durometer (stiffer) foam that creates a pivot point for your foot as it rolls over the ground. Karhus basically have a pivot where traditional shoes might have some form of medial posting. Needless to say, this is one shoe I would like to cut in pieces to see all the layers! (If only performing surgery on quality running shoes didn’t make me tear up.)

According to Karhu, the fulcrum design not only fights over-pronation, it also reduces vertical oscillation. In short, the shoe makes your foot roll so efficiently over the ground that you bounce up and down less, thus conserving energy.

Image from karhu.com/technology. The green line is Karhu; the red is everybody else.

According to Karhu, by reducing oscillation, you reduce other common evils like over-striding, braking with your heels, etc. The end result is a more consistent stride.

I’m not quite as clear on how the fulcrum controls over-pronation, but Karhu does have a video of a guy running pretty darn neutral. I think the basic idea is more efficient stride = less time on the heel to over-pronate, which is in line with the idea of controlling injury-causing foot movements by running on the mid- to forefoot.

If you read my previous review of the ASICS Super J33, you know I’ll be giving these shoes’ pronation control abilities quite the workout!

Flow3

The lightest of the four Karhus at Rogue is the Flow3, which Karhu promotes as durable enough for an everyday trainer yet light enough for a racing flat. Even I, one of the more “stability-friendly” Rogues you’ll meet, find the “racing flat” claim a stretch. The Flow is by far the most flexible of our Karhus, and not too cushioned, but it’s no Adios Boost.

Well hello, Flexy.

As the pic illustrates, there’s not a whole lot of cushion/stiffness/etc. in the front half of this shoe. This can be great if you like a lot of flexibility and ground feel, but for me it caused that pesky metatarsal joint on my left foot started whining a bit.

Note: Metatarsal pain is a problem for me in most lightweight shoes – or any that are particularly low on the cush-factor – but if you are prone to it yourself, you may want to watch out for it in the Flow.

Another element of the Flow that I decided to attribute to the lack of cushion (and this was definitely the standout factor for me) was that I could feel the fulcrum almost as much as the posting in a support shoe. Weird, right?!?

I won’t say there was a lot of pronation control per se (nor would I expect it in a lightweight trainer), but I could definitely feel something under my arch. Very odd. Perhaps this gets less noticeable as you adapt to the fulcrum?

On the run, the Flow definitely rides like a low-drop shoe. Granted, at 5mm, this is far from the lowest shoe on the floor, but I was legitimately afraid to land on my heel. I’m not sure if that was due to forward propulsion from the fulcrum or just not wanting to land on the stiff heel, but either way, for me, the Flow did encourage a forefoot strike!

One last noticeable element of the Flow was the “heel collar” on the insole, between the heel and the ankle. I noticed no such feature in the other three Karhus, which was a shame, because it fit perfectly! The little padded nobs clinched the shoe in place: I couldn’t have made the Flow slip if I tried! (And I did.)

Heel collar on the Flow.

Flow3 Verdict

Pros: NO heel slippage, low drop, encouraged a forefoot strike.

Cons: Felt “piece-y”. I could literally feel each separate piece of the shoe. I also expected a lighter feel given the lack of cushioning.

Overall Verdict: If anything, this would be a quality workout shoe for me. While I don’t think I’ll be adding the Flow to my regular rotation, another Rogue termed it “One of [his] favorites. The only Karhu [he] likes to run in.” Consider this a good reminder that every foot is different, so you should always take your shoe reviews with a grain of salt! (Or silica pellet.)

Karhu Flow3 Specs
Weight	M: 8.6 ozW: 7.3 oz
Heel/Toe Drop	M: 5.1 mm (23.3 mm/18.2 mm)W: 5 mm (18 mm/13 mm)
Design Features	Construction: Compression molded EVA foam midsole Karhu Fulcrum technology (higher durometer EVA) High-abrasion rubber on outsole Open mesh upper
Available Sizes	M: 8-13W: 6-11
Available Widths	Standard
MSRP	$115