The The breweries are calling and I must go shirt bulk of body heat is stored in your core, where blood flow is concentrated, which leaves your extremities vulnerable to cold. “Heat regulation is all about your head and hands,” says Corbin, who wears running mittens, headbands, and hats by Saucony, one of her brand sponsors. Pulling a neck warmer up over your nose shields you and warms the air you exhale and breathe in—like a natural humidifier. Megan White, the New York–based founder of All Women’s Tri Team and five-time Ironman finisher, finds that “good socks are essential” and swears by Swiftwick’s Pursuit Four Ultralight. For comfort and traction, Davison wears cycling shoe covers, such as Garneau’s Thermax II, and switches to studded bike tires. Rebecca Mehra, a Bend, Oregon–based professional middle-distance runner, straps Yaktrax cleats over the soles of her sneakers for safer snow workouts. “You can also put bolts on the bottom of shoes for grip—sometimes local running stores will do it for you,” she says.