There are products and concepts that on first glance just don’t really make sense: Like cruising around the United States in a 400 HP Porsche 911 at a leisurely 55 mph, or all wrapped up in an expedition jacket filled with arctic goose down to slurp mulled wine at the holiday street faire, or perhaps outfitting a ski boot with GORE-TEX technology. Think about it: GORE-TEX = highly breathable; plastic = zero breathability. Makes no sense. Or does it?
Wick moisture away from the feet
Flashback: 1998 in the Venezuelan jungle, 35 degrees Celsius, 98 per cent humidity – not generally considered the ideal environment for the functionality of GORE-TEX products. Still, the then-managing director of GORE-TEX footwear, Thorger Hübner, was always one for extremes. So we didn’t just test footwear in this hot and humid climate. In fact, we also had passionate discussions about the logic and illogic of GORE-TEX technology in different extreme applications. One example: plastic footwear for alpinists and skiers. The foot climate in a ski boot is normally not the greatest, and at some point you’ve snuggled down into your own pool of sweat. But moist or wet feet increase the risk of abrasion and blisters, plus heat dissipates more quickly in that kind of climate. His rationale went something like this: “You only have to wick moisture away from the feet and make sure it doesn’t come back. And that’s exactly why GORE-TEX products make sense.”
We feel like professional athletes
Indeed, that concept was adopted in subsequent years by some brands for ski touring boots, such as Dynafit or Lowa, but the climate of feet in a ski boot had never been fully researched. It was thus high time for a real test. A scientifically based test. It was time for a real winter.
A few years later, at the Sports Science Institute in Kassel: The launch of the first fundamentally sound test of the foot climate in ski touring boots under the direction of Dr. Dr. Hans Herbert Vater, who was introduced to us with the diminutive “Hansi”. First, my three colleagues and myself were checked over by a physician (“slightly overweight”, they noted about me, and I am still a bit miffed about that!). Then we were hooked up with wires from head to toe, with temperature and moisture sensors also on our feet. Then we pulled on ski boots with a newly developed prototype of a GORE-TEX liner and did a simulated ski tour on a special treadmill: Four kilometres an hour, in shorts and t-shirt, breathing with difficulty whilst wearing a snug and oppressive mask used to measure oxygen uptake and carbon dioxide output (“spiroergometry”). At regular intervals, Hansi took a blood sample from our ear lobes and measured it for lactate levels. We really felt like pro athletes!
Using mobile spiroergometry on the glacier
A few weeks later, up on the Hintertux Glacier in Austria, the same procedure all over again, only this time in a real-life situation and with a mobile spiroergometry unit carried in a pack on the back. Hansi warned me as I headed out: “Be careful on the downhill. That thing costs more than your VW Sharan.” Catching rather questioning looks from other skiers, we marched up the piste, wheezing and sweating in our masks. Hansi roughly explained the logic behind all of this effort to us like this: “To attain scientifically sound results about foot temperature and moisture in typical conditions on a ski tour, we must ensure that every single tester is working in his or her individually appropriate training zones. For example, if you go too fast and move into an anaerobic zone, that would invalidate the measurements.” All winter long we raised eyebrows at our area mountains, heading out with our feet wired up. Results each time were convincing. On some outings, we could actually pour the sweat out of our plastic boots! GORE-TEX technology did indeed work in ski touring boots – assuming the materials and the construction of the liner enabled moisture to be wicked away. Countless boots using different materials and types of construction were created and tested, always with the goal to find the optimal combination. Then a new challenge was added: Today’s liners are made of thermo-mouldable materials and foams and, as a rule, are not breathable. But we also cleared that hurdle in the end with our current brand partners Scott and Dynafit. Scott places breathable inserts in all the right places, whilst Dynafit on the other hand adds perforations in the liner that allow moisture to evaporate. Results are impressive with both: fantastic climate comfort that is in particularly noticeable on long tours. Twenty journalists even came away from a demo event at Jungfraujoch in April 2015 quite impressed – and, as of this winter, so too will all ski touring enthusiasts be equally impressed.