If you are like the majority of the population, you probably spent more time this holiday season eating and entertaining and not dedicating as much time to working out. Time to come back to reality and get your routine back on track. The winter season is in full swing and you want to make sure you'll look fabulous in those swim trunks you bought for you your vacation somewhere south. Even if there is no summer vacation in your upcoming calendar, a couple more months and spring will be here, so another good reason to keep yourself fit.
To get back on the track, work out no longer than 45 minutes for first couple of weeks until you get back into a routine. Instead of doing your usual routine, for the first couple of weeks perform workouts consisting of mixed exercises for different body parts, up to 5 different exercises with 4 sets and 8-12 reps. (bench press, overhead press, lat pull up, dips, bent over row, etc.).
Do your workout between 3 and 4 times per week. Be creative and use different exercises each time. What I find works best is to split cardio workouts on the days when i do not do weights. I enjoy my workouts but do not want to spend more than 1 hour in the gym, so on alternate days when I do not do weight training, I do 45 minutes cardio and/or legs. I would like to suggest you to change your routine on regular base at least every 3-4 months.