Challenge: Accepted

Rob Corkran photo Jan Guenther is easy to admire: the owner of Gear West Ski and Bike Shop in Minnesota, she is a perennial age-group winner at the American Birkie and World Masters Championships. In the summers she's an Ironman triathlete, an open water swimmer, an outrigger paddler, a trail runner, a bike racer. But at age 65, there was one thing she hadn't explored yet, and that was back-country wilderness skiing at altitude. So when her friend suggested they tackle the 40-mile point-to-point Grand Traverse back-country ski race this last winter, traveling high-mountain wilderness from Crested Butte to Aspen, she was all in. So that meant a scramble to learn a whole new sport -- new skis and boots to try and buy, new hydration packs and safety equipment to try and buy, new experts to talk to and learn from -- and somehow figure out a way to take all the sea-level Minnesota-flat training and transform it into trackless backcountry skills at altitude. She and her friend made...