Calorie Cycling

Calorie Cycling, also known as “Calorie Shifting” or “Zigzag Dieting”, is a system used to limit fat loss plateaus when on a calorie controlled diet. It is not a diet in itself but a method of manipulating your metabolism to avoid homeostasis (the body shutting down to prevent weight loss) and muscle catabolism (the body breaking down lean muscle mass for fuel).

Although clinical research on the effectiveness of Calorie Cycling is limited, people who use it report greater overall fat loss with less frequent plateaus and less lean muscle loss.

The Theory Behind Calorie Cycling

Calorie Cycling aims to limit the body’s natural tendency toward self preservation, by tricking it into thinking that it’s not actually on a diet at all.

Because fat loss relies on a total calorie deficit over time, rather than a consistent daily deficit, it’s possible to alternate days of calorie-deficits with days of calorie-surpluses and still loose body fat. While your initial fat loss may be less dramatic than with a sustained calorie deficit, ultimately you will achieve better and longer lasting results.

Psychologically certain people find Calorie Cycling easier to adhere also, which is another added bonus. Cycling their calorie intake makes them feel as though they are getting “cheat days”, and timing these higher calorie days with their training days means that they have plenty of energy when they need it most.

Example of a Calorie Cycling Diet for Weight Loss

Calorie Cycling works on basic mathematics. Firstly you need to determine how many calories you should be eating to maintain your current weight, how many kilograms of fat you want to lose, and your intended workout schedule and intensity. Once you have determined these things, it’s simply a matter of working out how you are going to stagger your calories across the week and still achieve the necessary deficit by the end. For example:

A 30 year old male who weighs 82kgs, is 183cm tall and trains three days a week needs to eat approximately 2500 calories per day (or 17,500 per week) to maintain their current weight. To lose 0.5kg of fat each week they need to create a weekly deficit of 3,500 calories (05.kg of fat contains roughly 3,500 calories), which means they need to total about 14,000 calories for the week (17,500 - 3,500 = 14,000 calories).

A traditional diet for this scenario would look like this:

Monday: 1998
Tuesday: 1998
Wednesday: 1998
Thursday: 1998
Friday: 1998
Saturday: 1998
Sunday: 1998

Total for week: 13,986

Calorie intake is the same each day resulting in a 3500 calorie deficit at the end of the week and, theoretically, a 0.5kg fat loss. The problem is that they may also experience a drop in metabolism, due to homeostasis & catabolism, which causes a plateau that can only be rectified with a further calorie deficit or increase in activity level.

The same scenario on a Calorie Cycling diet might look like this:

Monday: 1998
Tuesday: 1599
Wednesday: 2398
Thursday: 1998
Friday: 1799
Saturday: 2198
Sunday: 1998

Total for the week: 13,998

You still end the week with a 3,500 calorie deficit but you achieve this by cycling your calories up and down each day, rather than keeping them at a steady daily rate. Your body has no idea that you are restricting your calorie intake so you are less likely to go into homeostasis, you are matching your high calorie days with your training days so you are less likely to dip into your lean muscle mass as a fuel source, your metabolism stays elevated as a result, and your total fat loss over time is greater