It's the Monday after the Thanksgiving holiday, and this evening health clubs everywhere will be jam-packed with remorseful, food-hungover gym-goers attempting to exorcise (almost a pun!) their Turkey Day demons. If you're planning on working out tonight, better get there early, as every elliptical will be occupied by some twenty-something woman furiously pedaling off that third piece of pumpkin pie, and every bench press will be taken up by some guy sweating that cup of gravy. It won't be pretty. Which is too bad, because all that hard work isn't going to tip the calorie-balance scales in anyone's favor.
It's said that the average American puts away 3,000 calories at Thanksgiving dinner and easily eats 4,500 calories on the day. A 150-lb person burns little more than 100 calories for every 10 minutes he or she spends on a cardio machine, which means that the 500-600 calories burned in an hourlong workout---the workout you'd do even if you hadn't binged over the weekend---are kind of pointless when it comes to restoring calorie balance.
Now that's not to say you shouldn't work out tonight---only that you shouldn't expect it to be your salvation. What takes far less effort and is far more effective in terms of atoning for Thanksgiving excess is simply cutting back on total calories for the next week or so. You're not going to run 5 miles every single day, but you can easily trim 500 calories from your daily intake, whether by drinking less soda or having yogurt and fruit for breakfast instead of a bagel with cream cheese.
This should get you back in balance just in time for next weekend, when you can once again ruin all your hard work at the gym with a plate of hot wings and 10 or 12 beers. Salud!