Every since last winter I had been wondering how I hadn't gained any weight although I didn't do diddly squat in terms of exercise. I sailed through the holidays eating whatever I wanted, never biked or went to the gym at all, and actually lost a couple of pounds. It was the biggest mystery.
Just last week during the cold snap I realized the answer when I noticed I was hungrier than usual. I spend a lot of time outdoors in the winter stalking birds, and for me just being outside in the cold forces my body to work harder to stay warm, thereby burning stored calories.
You gotta love how that calories-in, calories-out equation works! Simplicity at it's finest. 