GORE-TEX brand athlete Greg Hill might need to break out a supercomputer to keep up with his annual elevation—the Canadian ski mountaineer skied 2,000,000 vertical feet in a year. That many zeros demands a lot from gear, and the aptly named Hill finds himself well-positioned to give feedback to industry heavyweights about how to create fabrics and fits that meet his performance standards. After all, if the gear can survive 2,000,000 feet, you can trust that it'll stand up to just about any challenge.

Gear can be the decisive point on a trip. There are so many other hazards to deal with that I have to completely trust my clothing to do what it is intended to do."

"To be able to go far in the mountains with my equipment is a serious task," Hill said. "Gear can be the decisive point on a trip. There are so many other hazards to deal with that I have to completely trust my clothing to do what it is intended to do." For Hill, that means working with both the fabric manufacturer and the brand using the material to create a finished garment (Hill is also sponsored by Arc'teryx). "With GORE-TEX products it's all about the fabric—its durability, breathability and overall feel," he said. "When I work with Arc'teryx, I provide feedback so that they can maximize the GORE-TEX product technology." Ski mountaineering comes with challenges that push apparel to the edge of performance demands, especially when worn by world-class athletes. Ferocious weather conditions, including high wind, precipitation and damp cloud cover exacerbate the challenges of the stop-and-go nature of the sport. Athletes are pushed deep into the pain cave on the ascent, then must pause to either negotiate a tricky spot or prep for the descent, before ripping back down. That means for any apparel to live up to Hill's standards, it has to serve many purposes. "The environment in ski mountaineering is constantly changing," Hill said. "It's rarely, if ever, the same all day. You begin in the dark cold valley, climb up through the moist clouds and get blown around by the winds on the summit. Then you ski back down for thousands of feet through kilometers of varied terrain. The fabric has to be able to address the demands that come with all those conditions—it's a serious challenge." As Hill approaches his 40th birthday (he's planning to celebrate by ski touring 40,000 feet that day), he's put countless products through their paces over enough vertical miles for multiple lifetimes. In other words, he knows exactly what to reach for when packing for an expedition: an e-reader, his journal and "a three-layer, ready-for-anything armor piece, top and bottom." And if there's one piece in particular he's learned the hard way to value, it's this: "a pair of underwear with a GORE-TEX fabric patch in the front. it prevents unnecessary coldness!"

Catch Greg Hill in action with 30 other outdoor professionals this spring on the GORE-TEX Experience Tour. This year, we're hitting the slopes and sea in Lofoten, Norway. Enter to win a spot on this once-in-a-lifetime expedition.