It’s tough for resort skiers to regulate their temperature. On the lift ride, you want to be protected from cold, wind, and snow. But slapping your way through a bump run, the jacket that kept you comfy on the lift will likely trap too much heat and leave you sweat-soaked by the bottom of your run, which then makes it harder to stay warm on the next lift ride because you’re wet.
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Many jackets have attempted to respond to changes in body heat as you become more or less active. The usual solution is pit zips, which are often awkward to operate and ineffective. Some have used body mapping to reduce insulation in areas of the jacket that tend to overheat, like the area around your armpits, and to better insulate areas that tend to chill quickly, like your belly and kidneys.
Thrym ski jacket takes a multifaceted approach that uses continuous air movement for non-stop body temperature regulation by combining graduated insulation with mechanical heat clearing that’s easier to use and more effective than pit zips.
The four-way stretch Thrym jacket is insulated with 80 grams of Primaloft Infinity, a top of the line synthetic. On the jacket’s interior, upward angled raised pods of goose down add extra insulation on your back and funnel body-warmed air into the spinal cavity of your jacket.
Helly’s Flow System turbocharged mechanical venting is anatomically body mapped not only for warming but also for cooling. Open the large front ventilation zippers and the smaller back ventilation zippers to create negative air pressure that sucks excess hot air away from your body through the back airports, much like the vents in a bike or ski helmet suck sweat away from your goggles and out the back. Regulate your heat clearing in the Thrym with incremental zipper adjustments. Airflow makes the Thrym 20 percent more efficient at regulating body temperature than jackets without the system.
The Thrym has an athletic fit and uses Helly’s Tech Professional waterproof breathable fabrics. A zip-away snow skirt, goggle cloth, and ski pass pocket make it user-friendly on the hill, and RECCO lets patrol locate you in an emergency. Articulated arms give it superior fit when you’re in motion. Available fall 2013, $900; .