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Competitor editor-in-chief Brian Metzler takes a look at the all-new Karhu Flow Tri Fulcrum shoe.
Typically running shoes are designed and updated based on loads of input from designers, engineers, biomechanists, sales people and marketing gurus.
But Karhu got the inspiration for its new Flow Tri Fulcrum shoe from some guys who were tinkering in a triathlon shop in Belgium.
“We heard about a shop that was adapting our Flow Trainer shoe for triathletes by putting a Velcro strap onto the shoe,” says Huub Valkenburg, CEO of Karhu, a 99-year-old Finland-based brand. “They take their triathlon very seriously in Belgium, you know. The shop had been making them for anyone who brought their shoes in. It’s a great idea so we thought we should probably make them ourselves.”
That shop, Runners Service Lab, in Zwijndrecht, is no ordinary shop. Since its inception in 1980, RS Lab has been known for its application of leading-edge science in helping runners find the right pair of shoes, building custom footbeds and using high-tech equipment to keep athletes healthy. It uses a force-plate treadmill and high-speed cameras to analyze the precise shape of a runner’s foot in motion and high-tech scanning devices to examine a runner’s back, legs or hips to search for abnormalities and imbalances.
Along the way, the guys at the shop have learned a thing or two about tweaking shoes to fit an athlete’s exact needs.
“To make the story complete, when I was working for Saucony we asked RS Lab in 1995 to rebuild shoes for Luc Van Lierde, also with a strap,” says Eddy D’Hondt, general manager of the RS Lab. “And shortly after that he won Hawaii twice and still is record-holder. The strap is a winner!”
The Flow Tri shoe is modeled after Karhu’s lightweight, neutral-oriented Flow 4 Trainer Fulcrum training/racing flat with a one-piece airy mesh upper, moisture-wicking collar and Karhu’s patented fulcrum heel insert in the rear foot designed to promote an efficient gait cycle with the responsive injection-molded midsole foam. The Flow Tri has a two-piece closure system designed for fast transitions out of T2—a quick-pull stretch-cord lacing system to secure the front portion of the shoe and a Velcro strap that secures the medial arch and the lateral heel. (In the modified versions produced by the shop, the laces were cut back and laced through three eyelets.) Both versions of the shoe have a 8mm heel-toe offset (16mm in the heel, 8mm in the forefoot) and have sample size weights of 8.2 oz. for men’s size 9.0 and 7.1 oz. for women’s size 7.0.
The Flow Tri ($125; Karhu.com) is due out in March at select U.S. and European retail stores.