sure is.
Some people call it a "Free Day," others call it a "Cheat Day." Whatever you call it, it's definitely a good idea to "relax" your diet once a week and eat something you really enjoy, provided that you do it in moderation.
If you try to be too strict all the time, then you are only setting yourself up for cravings and bingeing (not to mention it’s no fun). Food is one of life's great pleasures so it's not productive to completely deny yourself of anything that you really want.
Pick a "cheat day," perhaps on the weekend, and give yourself permission to have one "cheat meal" of whatever food you want. Consider it your reward after a week of perfect eating and perfect training. If you eat five or six times per day (like you should be), that's at least 35 meals per week. If 33 or 34 of them are perfect, then one (or even two) "cheat" meals aren't going to hurt.
Of course, it also depends on what your definition of "pigging out" is. A single mega-high calorie binge of junk foods that are loaded with fat and sugar could set you back for days. There's never any excuse for "pigging out" and blowing your diet completely.
I also don't recommend taking an entire day off your diet; keep it down to one meal per week; otherwise it's too easy to get thrown off course and lose your momentum. Maintain your discipline and keep a steady routine including consistent meal timing and frequency. Remember, good day to day habits are the foundation of your success.
The amazing part is that if you've been on a strict diet all week long and you've been doing it consistently for a period of months, then allowing yourself to have a cheat meal can actually do more good than harm. It will satisfy psychological and physiological cravings and help prevent you from "falling off the wagon." It's human nature to want what you can't have or aren't supposed to have, so going too long without letting yourself relax a bit can lead to binge eating.
If you've been on a very strict low calorie and/or low carbohydrate diet, you might even find yourself leaner with fuller looking muscles after going off your regular diet and increasing your calories for a day. This is very common among competitive bodybuilders. They are often surprised (and irritated!) that they look better the day after the contest, after they've had the post-contest celebration meal of pizza, hamburgers, etc. Why? Because the months of severe dieting may have put their bodies into "starvation mode."
When you increase your calories and add foods that you've been restricting for a long period of time (fats and carbohydrates), this can actually speed up your metabolism and make you look leaner - it's like telling your body, "We're not starving anymore; it's safe to start burning more calories now." Not only can an occasional "cheat meal" make you look leaner, but your muscles will also fill out and look bigger and firmer because your glycogen levels will increase from the all extra carbohydrates you take in.
So the bottom line is, don't feel guilty about having a "cheat meal" once a week; it will probably do you more good than harm. Just remember, you must eat "clean," healthy foods the majority of the time if you want good results. Long term consistency is one of the most important factors in building muscle and staying lean. Don't use your "cheat day" as an excuse to totally blow your diet and never make junk foods a part of your regular, daily diet. Save them for special occasions or enjoy them once a week as a reward for a job well done.
