This is my first year to ride through winter. In the past what I've done to avoid winter weight gain was simply to walk and stand more. I wear a pedometer and try to be sure I hit that 10k mark everyday. I've also swapped out my traditional desk for a standing work station. I find that when I'm already standing, I naturally find myself moving more. One other trick: I set a timer so that after 50 or 55 minutes of inactivity, I move for 5-10 minutes. My office is on the fourth floor of my building, so sometimes I just walk down to the first floor and climb the steps again. Every little thing seems to help. Good luck!