I shamelessly copied some of the actual explanation from Steve Edwards over at “the straight dope” because frankly, even though I wanted to write an article about getting over an “eating plateau” and how you need to confuse your metabolism the same way you need to confuse your muscles to avoid stagnating myself, I wouldn’t be able to put it into words as well as he did.
If you all of a sudden stagnate in losing weight or leaning out you are probably under-eating. Eating and giving your body the exact amount it needs, without feeding it too much or too little is a really tricky task on itself. Pack this on top of the whole exercise routines and you face quite a challenge if you want to stay healthy and keep reforming your body.
Even though the beachbody nutrition guides give you a great help initial estimate on where to start when it comes to eating, everyone is different and those numbers always need adjustments the longer you keep working out. One way of determining what you need is that so called zig-zag approach.
Not to be confused with yo-yo dieting, zig zag is a technique that should be used any time you want to increase or decrease your daily caloric intake and can be used to find out what your caloric intake should be. Instead of moving straight to a new daily caloric number you move in smaller increments on a staggered schedule. Here’s an example of how it works:
Say, for example, you’re eating 1500 calories a day and have been for a period of time where you’ve lost weight. Now your weight loss has stagnated. This is one of our most common scenarios because the new, fitter you has a different body composition than the former you. You have more muscle and a higher basal metabolic rate (BMR). In order to continue your weight loss you need to eat more because 1500 calories isn’t enough—even though it once was—and now your body is reacting by slowing its metabolism and releasing cortisol in a protective response (often called starvation mode because this is how your body would respond to being starved). I personally like to call it “hibernation mode” since, seriously, people are still so bound on thinking that “starving” yourself will net you the best weight loss results. Well let’s not go there, that’s a whole topic on its own.
At times this could be a lot more because huge caloric reductions can work in the initial stages of a program for deconditioned people. Let’s say that the individual in question runs a caloric calculation and figures they need 2,500 calories per day.
Weight times 10, plus 10-30% for daily activity depending on how active you are, plus the estimated caloric burn of your exercise.
You don’t want to jump straight to 2500 calories. First, it would create some shock to your system and, second, it may be wrong as those calculators only give ballpark figures. The most effective thing to do is to zig zag your caloric intake. In this instance I would recommend eating 2000 calories per day for 3-4 days per week and 1500 calories the other days. Then you note how your body responds, which I would expect to be positively on the higher caloric days and by feeling famished on the low-cal days.
You want to be energized but not hungry, so after a week or two of this I would bump up to around 2200 cals for 4 or 5 days and 1500 cals on 2 days for, maybe one week. If I’m still starving on the low days try bumping them up to 2000 and see how you respond. Use this tactic until you regulate, which means that you’re energized but not hungry and also not full. You can tell when you’re eating too many calories because you’ll begin to feel full, you won’t digest your food between meals, and you’ll feel more lethargic at the beginning of workouts.
Zig zag dieting works whether you need to reduce or increase your caloric intake, and whether you need a subtle change or dramatic change. There is no numbers formula except to increase/decrease in small increments between 200 and 500 calories a day and to zig zag your caloric intake two to four times per week. Then you just listen and let your body tell you how much you should eat.