Can you let your exercise routine slide a little during the holidays and still stay fit? Yes. Missing a few sessions is no reason to throw in the towel. For most people, just one 30-minute session each of weight training and aerobic exercise a week can prevent significant fitness loss if you can't maintain your usual workout schedule. It takes several weeks of inactivity for complete deconditioning to happen.

But mix in physical activity whenever you can since it counteracts stress and will help you weather the season feeling more energetic and upbeat. If time is tight, consider taking a walk—at the mall, on your lunch hour, or as a break from your relatives. Three brisk 10-minute walks provide all the benefits of half an hour of continuous exercise.

Read more on getting more from your walking workout and how exercise can help you beat stress.