Article by Sam Winebaum with Dominique Winebaum
We have long been obsessed here at Road Trail Run by apparel which is effective for running comfort at the extremes of heat and cold. In warm weather perceived and real comfort comes from how cool one's skin feels and in minimizing wet cling of fabric to the skin. Cooling using fabrics can come from
- a variety of chemical and other treatments (Columbia Omni-Free Zero, 37.5)
- the actual structure of the fabric to allow not only rapid evaporative cooling but also less clammy cling to the skin when wet. The approach Coolcore takes.
- fiber selection,for example Titanium fibers in adidas Climachill article here to actually conduct heat away from the skin
- reflective outer layers on the fabric (Columbia Omni-Shade Sun Deflector
Of course, fabric color is also a factor with lighter colors generally less heat absorbing. In colder conditions staying dry is the key and many of the same characteristics of rapid evaporation and fabric structure needed in heat can apply to keep garments drier and more comfortable in cold. The differences generally are the fit, generally snugger in cold, deeper structures or "fuzzies" on the skin and on the outside to insulate being main difference between hot and cold weather comfort and performance.
Coolcore
We have long kept an eye on Coolcore a local to us Portsmouth, N.H, company. Their fabric technology (see
here) relies on structure to provide cooling and drying power and less wet cling. Coolcore achieves this by wicking, transporting moisture, and regulated evaporation. No added chemicals are used to achieve the performance and comfort of these synthetic fabrics. Early on Coolcore was involved and still is in cooling towels that when wet provide a distinct cooling effect as well as some licensing of the fabric technology into work wear and general athletics. For several years we have wrapped a Coolcore cooling towel around our neck during long trails runs, very effective and tested a t-shirt a few years ago that was effective in cooling but was a fairly crude slick feeling fabric with plenty of wet cling . We were eager to try their latest introduced at Outdoor Retailer in July and put it to the test.
Performance
Cool core had their fabrics tested on specialized equipment, and not just anecdotally via user impressions, at the
Hohenstein Institute, a 60 year old independent testing and research institute for the clothing industry The fabric was tested against 7 competitors and three competing technologies, un named but we might assume Climachill and Columbia were in the mix. The testing results are
here and also illustrated below. Coolcore won several awards for fabric technology innovation.
In the Hohenstein testing Coolcore came out with the highest performance scores in the three tested categories of Cooling Power, Drying Time, and Wet Cling. One must always take such company sponsored testing with a grain of salt and actual on the run use in varying conditions of humidity, temperature, sun combined with color of garment, wind, if used under another layer along with of course each runner's preferences also go into the mix.
This said when compared to standard technical t-shirts, and other cooling claiming shirts on many runs and hikes in varying conditions and even cold conditions, in combination and overall, the Cool Core outperformed any of our many high performance and cool claiming shirts.
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