Wear a Pedometer
It's important to keep track of how active you are during the holidays. Chances are that when it's chilly and dark outside as you're leaving the office, you're going to be less active than when it's warm and sunny when you head home from work. To make sure you're staying active during the winter season, wear a pedometer to keep track of how much you're moving around.
A general rule of thumb is that you should walk about 10,000 steps daily -- about 5 miles (8 kilometers) -- to maintain a good level of fitness. By wearing a pedometer, you'll be able to check if you're maintaining your baseline of fitness and adjust if you're not. If you find you're falling behind, take the stairs at the office instead of riding the elevator or park a few blocks away from the restaurant if you're meeting your friends for a holiday meal.