The Bodybuilding Diet- Simplified

By Bill Dobbins

Founding Editor of Flex Magazine

The purpose of the bodybuilding diet is to achieve two contradictory goals – to maximize muscle mass and minimize body fat.  Doing either one can be difficult, doing both at the same time would seem to be almost impossible – except that generations of bodybuilders have figured out, on the basis of trial and error how to get this done.

As a result, bodybuilder are the best dieters in the world.  Even a failed bodybuilding diet might well be considered highly successful by the standards of the real world.

There are so many ideas about what kind of diet is best for bodybuilders that this can become very confusing.  But after decades of studying this and writing about, after having interviewed many dozens of advanced male and female bodybuilders on the subject, I have come up with a way of describing the bodybuilding diet process in the simplest possible terms.


Body fat is just stored excess energy – calories.  If you ingest more calories than your body burns up, you gain fat weight.  If you ingest fewer calories, you are in negative caloric balance, and you use up stored body fat.

Negative or positive caloric balance is a matter of food intake vs energy used up exercising.  To burn up body fat you can eat less and/or exercise more.

There are lots of other metabolic factors that mediate this process but the most significant aspect is this food/exercise equation.


All food consists of three macronutrients: protein, fat and carbohydrate.  Protein is made of amino acids and complete protein is that which consists of a sufficient number of amino acids in the proper balance to allow the body to use it to build muscle tissue.  In general, animal flesh, milk, eggs and fish are examples of complete protein, with a high level of net utilization of the amino acids.  Foods like rice and beans give you some complete protein but a relatively small amount.

How much protein do you need.  In general about 1 gram for every kilo (2.2 lbs) of lean body mass.  You can eat more, but once you have enough protein any additional simply counts as calories.  Yes, eating too much protein can help make you fat.


All macronutrients are a combination of carbon, hydrogen, oxygen and (with protein) nitrogen.

Fat involves a structure of these molecules which is much more energy-rich than the others.

Protein and carbohydrate are about 4 calories per gram; fat is 9 calories per gram.  Therefore, in terms of maintaining negative caloric balance is it obvious you need to restrict the amount of fat in your fat.  Not eliminate it entirely, nor cut back too much.  There are valuable nutrients in fat, such as fat-soluble vitamins, and women’s biology requires a certain amount of fat intake.  But you need to regulate how much fat you eat as part of keeping track of your overall caloric intake.


All carbohydrates are some kind of sugar.  Carbs can be all sorts of vegetables, grains and fruits.  As far as diet is concerned the major difference is in something called glycemic index.  This is a measure how fast the sugar is converted into glycogen and gets into the blood.  Foods with a high glycemic index like fruits (fructose) convert quickly, green vegetables have a low glycemic index and convert slowly.

Glycemic index is now used in place of what was formerly designated as simple or complex carbohydrate.

You often see discussions of something called ketosis.  Ketosis is a metabolic state that occurs when the body is carbohydrate deprived.  Certain metabolic functions such as brain activity depend for fuel on the availability of carbohydrate.  In its absence, fat is broken down and ketone bodies are produced which serve as an emergency source of fuel.  When you are in a state of ketosis you lose a lot of water weight, appetite tends to be diminished and the body metabolizes a larger percentage of lean body mass (muscle) for energy.

Ketosis is not a very health or efficient state for your body to remain in for any length of time.


Given the above macronutrient information, here is the recommendation.

PROTEIN – ingest about 1 gram per every 2.2 pounds of lean body mass.

FAT – Reduce fat calories to some reasonable amount to lower caloric intake.

CARBOHYDRATE – reduce carb intake until you are almost, but not quite, in ketosis.


You can monitor your carb intake by buying a product called Ketostix as a pharmacy.  These are strips that change color when exposed to urine if there are ketone bodies present.  You can reduce carb intake to the minimum amount for health and energy by detecting the point where you go into ketosis and then increasing carbs enough so you don’t get a reaction from the Ketostix.


When you eat enough protein and reduce the amount of fat you ingest, the two variable left are how many carb calories in your food – which can be increased or decreased as necessary, and how much energy you expend with exercise


Keep in mind that the body is not in a state off equal demand for nutrients all the time.  It is in the largest state of demand a few hours after vigorous exercise.  If you work out in the morning, the body will be in much less demand for nutrients later that evening than in the morning or early afternoon.  Also, on rest days, when you are not training, the body will be in less demand for nutrients, so you should reduce your caloric intake on days off.


The body reacts to diet changes slowly.  Ms. Olympia Lenda Murray told me she used to start a very strict diet in July for a November contest, and despite total discipline she would not see much change in her body for a full month.

So here are two recommendations –for one, give your contest diet a full 12 weeks.  That is the time it takes most bodybuilders to get in shape.  If your own metabolism is faster or slower than this you will find out from experience.  For another, try not to be too overweight when you start your contest diet.  That is, regulate your body weight off season so you don’t have way too much to lose.


Cardio is good for metalizing additional energy.  But isn’t very good in terms of maintaining the most amount of lean, hard, mass.  Since the 1970s, there have been some bodybuilders who have placed an over-reliance on excessive cardio to make up for lack of diet discipline or trying to unreasonably speed up the process.  The result has generally been they ended up looking a lot worse than they should have.  Their bodies looked too soft and their workouts suffered due to increase systemic fatigue.

One bodybuilder who made this strategy work, at least for a while, was Lee Priest. He would let himself get 50 pounds or more over his contest weight and then burn off the excess with several intense cardio sessions a day.  But this worked for Lee when he was in his early 20s, much younger than most top pros, and was much less effective when he got older.