Wondering how cold cranks up the calorie burn? Your body thrives on consistency—specifically, a core temperature of 98.6°F. When you’re exposed to the cold, your body’s built-in survival mechanisms ...

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Brrr! It’s cold out there—but bundling up and braving the chill to exercise comes with its perks. Because ...