» Radiation Any time air temperature is below 98.6°F, bare skin vents heat. Fix Cover exposed skin with gloves, a hat (A), neck gaiter, and a face shield. Go inside a shelter, which traps body heat.
» Evaporation During a tough hike, cooling sweat could drench your layers—and drying them wastes energy. Fix Adjust pace and clothing to avoid excess sweating, and slow down 30 minutes before reaching camp to let body heat dry baselayers.
» Convection Moving air cools skin fast—that’s why windchill makes temps feel colder. Fix Wear windproof outer layers, seek shelter (B), and plan a route with minimal wind exposure, like a forest or a canyon.
» Conduction Contact with frigid surfaces siphons heat as the temperatures equalize. Fix Insulate sleeping and sitting surfaces with your pack or sleeping pad (C), or even dry leaves.
Eat Your Way to Warmth
» Switch to a high-fat diet. Calorie-dense foods like chocolate, nuts, and cheese metabolize slowly, prolonging digestion’s hour-long, body-warming effect.
» Drink green tea. Catechin-packed tea boosts metabolism, and hot drinks
in general cause sensors in your
arteries to shuttle more blood to your extremities, making you feel warmer.
» Add oil and spices. Olive oil is a caloric H-bomb, and eating mild spices (ginger, nutmeg, and cinnamon) increases blood flow to the skin. Beware of capsaicin in hot chilies; it’ll make you sweat.