As I mentioned in my first article about fat loss, nutrition is the real key to unleashing the effectiveness of aerobic exercise as well as weight training. In this article I'm going to write about the general nutrition principles that you should follow in order to have a muscular and well defined physique. These principles are based on what physiology states on the matter and/or my personal experience with them. Getting defined through dieting requires you to maintain the balance between the two hormones that control the "fat storing" and "fat releasing" processes:

Insulin and Glucagon

Here in Italy the current trend is for nutritionists to recommend that their patients figure out how many calories to taken in based on their own bodyweight and then recommend that these calories fall into the following nutrient percentages:


60% carbohydrates
15% proteins
25% fats
This macronutrients' distribution comes from the deep-rooted idea that carbohydrates are the main source for immediate energy and are extremely important for facing every day's psycho-physical efforts. Thus, they recommend a high percentage of carbs. Fats are meant to serve as a carrier for lipo-soluble vitamins and are indispensable for vital functions. Along with protein, they are an integral part of cellular membranes.

Protein is required in order to satisfy plastic requirements and that percentage is believed to be enough! At first sight, nothing appears wrong...but according to what physiology says, everything needs to be reviewed!


First of all, hormonally speaking, these macronutrient percentages do not assure any balance in the Glucagon-Insulin axis, nor the proper protein intake per kg of Fat Free Mass (FFM) also known as Lean Body Mass (LBM).
Second, the glycogen deposits are limited in the human body. An average person has about 300-400 grams capacity for glycogen in the skeletal muscle tissue and about 60-90 grams of it in the liver. (Glycogen is a polymer of glucose molecules, a very long chain composed of many glucose molecules.)


This second aspect is important for one main reason:

If you consume carbs in such high amounts (60%) you are most likely overfeeding your body when your glycogen deposits are already full; the excess carbs will be turned into triacylglycerols and then carried into adipocytes. In other words, it will turn into ugly fat!

This macronutrients-induced hormonal state and the low protein percentage won't lead to optimal fat loss. Make sure don't confuse weight loss with fat loss.
Accordingly to both food-induced hormonal responses and my personal experience, the right percentages of macronutrients for fat-loss while maintaining your muscle:


40% Carbs
30% Proteins
30% Fats.
How do you estimate your caloric intake? Use the calculator below!


Calculate Your Macronutrients Intake!

Enter Your Bodyweight In The Appropriate Box Below:

Your Bodyweight In Pounds: OR In Kilograms:

Your Body Fat Percentage: % (Do not enter the percent sign.)



Here is how it all works. There are several tables on the matter you could refer to, but none of them are reliable because they don't take into consideration one's individuality. One of the factors that contribute to one's individuality is their lean body mass. Considering one's FFM means FEEDING properly, not overfeeding, not underfeeding.

How To Start:

Use the skin fold caliper with the Jackson & Pollock 7 sites to figure out your body fat percentage. These are the 7 places you should measure the skin folds on your body. Follow the guide that came with your calipers.

Estimate your FFM in Kg. Here's how to do this: First of all, to figure out your weight in kilograms, take your weight in pounds and times it by .4536. For example, if you weigh 150 pounds, you would take 150 times .4536 and it would equal 68.04 kg. Then you need to figure out your lean body mass. If you estimated with the skin calipers that your body fat percentage was 10%, then minus 10% from your weight in kilograms.

So if you weigh 68 kilograms and have 10% bodyfat, your Fat Free Mass (FFM) would be 61.2 kg. (68 times .9 = 61.2)

Consume 3 grams of protein per Kg of FFM if you train really hard, otherwise 2 grams.
Divide the total protein intake by 0.75 to find the carb intake.
Divide the total protein intake by 2.3 (4.7 if you don't train really hard) to find the recommended fat intake.
Divide evenly your total macronutrients intake into 5 or 6 meals.
Make sure you consume at every meal the same dosages of macronutrients.


This will allow you to consume a 40-30-30 diet, which is favourable to keep the Glucagon-Insulin Axis in balance. Eating each meal at 40-30-30 percentages will assure you:

1) The carbs enter the bloodstream at a slower rate so that insulin levels don't reach a high peak.

When the carbs hit your oral mucous membrane, your salivary glands begin to secrete saliva which contains the alpha amylase called "ptyalin", a digestive enzyme that begin to transform starch into simple sugars.

This enzyme once mixed with the food containing carbohydrates continues its digestion up until it reaches the stomach. If PH in the stomach is very low because of HCL secretion induced by protein consumption, the alpha amylase enzyme digestion stops and thus carbs enteric digestion will be slower and their bloodstream entrance will be slower too. This is why it is better to consume proteins plus carbs at each meal for not eliciting a harsh insulin response.

2) The fat content will help you diet successfully. Once fat gets ingested, it triggers different processes like the release of the Cholecystokinin hormone (CCK). This hormone tells your "Brain Famine Center" that you are full. That's why a low fat diet puts you in a starving mode and makes you quit your dieting attempts. Fat content will also reduce the carb entrance into the bloodstream.

Let's suppose we want to help a healthy person who weighs 80kg and whose FFM is 70kg and Fat Mass is 10kg. Let's assume this person trains hard with weights, doing aerobics as well, and aims to get rid of excess body fat.

With the 40-30-30 diet he will consume:


210 grams of Protein (70kg x 3gr of proteins)
280 grams of Carbs (210g of proteins / 0.75)
91 grams of Fat (210g of proteins / 2.3)
The total caloric intake will be:


210 x 4kcal = 840kcal from proteins
280 x 4kcal = 1120kcal from carbs
91 x 9kcal = 819kcal from fats
Total kcal = 2779
With the Italian, old fashioned diet percentages it would have been:

2779 kcal x 60% = 1667kcal : 4kcal = 417gr of Carbs
2779 kcal x 15% = 417kcal : 4kcal = 104gr of Proteins
2779 kcal x 25% = 695kcal : 9kcal = 77gr of Fat


As you see, there's a sensible difference in the amount of macronutrients between the two kinds of diets. Calories are the same but hormonal responses are very different and consequently the aesthetic results in terms of fat-loss will be different too. Also the amount of carbs, 417 grams, in the 60-15-25 diet is very high.

If the muscle and liver Glycogen depots are estimated with a maximum of 400-490 grams total allowed in the body, 417 grams of carbs daily could be considered acceptable in theory, but this will still be revealed to be too much.

This is explained by considering that:


You don't train everyday and not always hard enough to justify that carb consumption.
You should consider that after performing an intense lactic acid anaerobic exercise (like weight training for muscle building purposes), your body will automatically convert some of the blood lactate either into water by oxidation (by which the hydrogen ion is removed from the molecule and thus the lactate is transformed into pyruvate, which enters the Krebs cycle inside the mitochondria and at the end gets converted into water) and into "GLUCOSE" through the CORI cycle which occurs in the liver. Yes, you are converting some of that lactate into glucose without consuming it directly through the diet.
Even if glucose is the only molecule needed from the brain to function at its best, remember that only the glycogen stored in the liver is accessible to the brain. Only liver glycogen can be broken down to assure adequate levels of blood glucose and to assure proper brain function. Liver glycogen depots are limited to 60-90 grams and get depleted within 12 hours.
If you eat the proper amount of carbs at each meal of the day you are assuring the proper amount of glycogen stored in the liver. But if you eat too many carbs, the high insulin response not only will lead to fat accumulation by decreasing your blood glucose levels but it will also act as a locking hormone.

This incapacity of the liver translates to a release of glucose through glycogenolysis for several hours, and consequently blood glucose levels remain too low for the brain to work efficiently. So the Hypoglycemia will trigger the signal for carbohydrate consumption, in other words, you feel like you are starving and start eating carbs again. It's a vicious circle.

Looking at the total protein intake of the 60-15-25 diet, it translates into almost 1.5 grams of proteins per kg of FFM. This low intake not only won't allow the subject to preserve muscle mass from catabolism while dieting but it will also hold back the basal metabolism rate from increasing.

In fact the Protein T.I.D. (T.I.D. translates into: THERMOGENIC effect INDUCED by the DIET) is 25%, Carb T.I.D. is 5%, Fat T.I.D. is 2%. It means that if you eat 25 grams of protein (contained in about 100 grams of natural tuna fish), which have a caloric value of 100 kcal, you will burn 25 kcal of those 100kcal for digestive and absorption purposes. This not only turns in a major caloric consumption but it will also speed up your metabolism. Instead, if you eat 100kcal deriving from 25 grams of carbs, only 5 kcal will be burned for digestive and absorption purposes.

Many people attempt to lose body fat by cutting their daily carb intake or totally abolishing it. On a high protein/low carb diet, all the glycogen that is stored drastically diminishes and thus won't be able to meet the body and brain needs. To face the lack of a "ready to use" energetic substrate (i.e. glycogen), triglycerides (fat) will be the preferred substrate to be used as fuel for energy. Great! But the process of generating energy from fat on a low carb diet is short-circuited.

Here's the biochemical explanation:

As I mentioned in my first article about: "How to get ripped using science", oxygen is the main molecule responsible for aerobic glycolysis and fatty acids degradation. The oxidation of the two substrates (glucose and fatty acid) occurs inside the mitochondria.

Let's take a deep look on how these two substrates get oxidized. The following steps will show you that a certain carbohydrate catabolism is necessary to oxidize fatty acids completely.

The Glucose Degradation (glycolysis) Consists Of Two Phases:


Anaerobic glycolysis - The first step of glucose degradation, which occurs in the watery medium of the cell outside the mitochondrion and without oxygen. Just so you know, this process represents a more primitive form of energy transfer that is well developed in amphibians, reptiles, fish and marine mammals.
Aerobic glycolysis - The second step of glucose degradation, which occurs inside the mitochondria and only with the presence of oxygen.


Anaerobic Glycolysis


Click To Enlarge
As shown by the figure above, the end product of anaerobic glycolysis is Pyruvic Acid. Either without oxygen or when oxygen uptake is lower than that required, Pyruvic Acid gets transformed into Lactic Acid and thus glycolysis stops.

Aerobic glycolysis only occurs if adequate levels of oxygen are available. In fact, oxygen (through different biochemical reactions) allows the Pyruvate to react with "Coenzyme A" forming a compound termed "Acetyl-CoA".

Acetyl-CoA enters the Krebs Cycle inside the mitochondria and by combining with Oxaloacetic Acid, generated from carbohydrate breakdown, Citric Acid gets formed.


Aerobic Glycolysis


Click To Enlarge
Once Pyruvate combines with "Coenzyme A" it can enter the Krebs Cycle as Acetyl-CoA and therefore the glucose molecule being completely oxidized to Carbon Dioxide and hydrogens; the hydrogens formed get transported through the respiratory chain generating 36 ATP molecules. Only two ATP molecules is the net energy gain from Anaerobic Glycolysis.

What you should have learned by now is that a molecule in order to be fully degraded to Carbon Dioxide and water needs to enter the Krebs Cycle (inside the mitochondria) and this of course depends upon optimal Oxygen uptake.

Now Let's Get Back To Fat

Stored fats represent the major source of energy that the body has. Either during physical exercises or stressor events, hormones like Growth Hormone, Epinephrine, Nor-epinephrine, Glucagon, activate "Cyclic AMP" through different biochemical reactions, which in turn activate either the LIPASE enzyme. The LIPASE is responsible for triglycerides to be broken down into fatty acids inside the adipose tissue and then released into the bloodstream and carried to other tissues to be oxidized. LPL is responsible for "Blood Lipo-Protein" complex to be hydrolysed.

At this point fatty free acid gets used by tissues like the Slow Twitch Fibers, which are rich in mitochondria organelles, for energy production. The fatty free acid needs to enter the cell first, then it needs to be activated (through different reactions) to be carried into the mitochondria for beat oxidation.

The end product of beat oxidation is a chemical compound that you should be familiar with by now: Acetyl-CoA. Yes, the same compound that derives from the reaction of "Pyruvate" with "Coenzyme A".

Now the Acetyl-CoA that is derived from beta oxidation needs to combine to Oxaloacetic Acid for entering the Krebs cycle. Oxaloacetic Acid is Pyruvate-dependent and Pyuvate in turn derives from Carbohydrate catabolism.

In a few words, let's say: Oxaloacetic Acid cannot be present if there is not Glucose breakdown; without "Oxaloacetic Acid" the "Acetyl-CoA" deriving from beta oxidation cannot enter the Krebs cycle and thus the impossibility for the fatty acid to be fully degraded.


Krebs Cycle

Click To Enlarge

So, in extreme conditions of glycogen depletion, Fatty Free Acids from adipose tissue and Acetyl-CoA from beta oxidation accumulate and get transformed by the liver into Ketone Bodies.

The high protein/low carb diet approach proves itself a very quick weight loss program for 3 reasons:


1) Loss of body water through increased urination.

Your body will increase urination in order to get rid of Ketone Bodies. You are losing weight, but the wrong weight. It is merely water.

2) Loss of body water dependent on glycogen depletion.

Muscle glycogen is about 18 grams per Kg of lean body mass. One gram of glycogen is linked to about 3.5 grams of water.
EXAMPLE: Let's assume a woman weighs 60 Kg with 20 Kg of lean body mass muscle.

20 Kg (of lean body mass) x 18 grams of glycogen = 360 grams of total glycogen
360 grams (of glycogen) x 3.5 grams of water = 1260 grams of water.

If we assume that the woman in the example cut all the carbs from her diet, she would lose 1260 grams of water!

This translates into a rapid loss of weight deriving from body-water only.


3) Loss of muscles for gluconeogenesis purposes.
Remember that your muscles use mainly glucose for energy production during weight training.
In fact this is well shown (and felt) when you perform 8-12 reps per set by the formation of lactate. That's why you feel your muscles burning during this range of reps! This means you are producing lactic acid which derives from glucose catabolism with the absence of oxygen.

If the diet is low in carbs, glucose (which is necessary for supplying energy during the lactic acid anaerobic metabolism, which is the main metabolism used for hypertrophy workouts) is produced through the gluconeogenesis process. This is a process by which the amino acids of structural muscle protein get transformed into glucose by the liver. In a few words, you are LOSING the hard earned muscles for glucose production!

(If you have your own personal trainer, ask him to check whether you are losing subcutaneous fat, body-water or muscle. Only an elite personal trainer will be able to make you lose weight mainly from fat while preserving muscles. Not everybody is able to do it!)

Glycemic Index:

Another factor that has to be taken into consideration is the kind of carb and its glycemic index. For many nutritionists 1 gram of carbohydrates is always 1 gram of carbohydrates.

According to these nutritionists eating 100 grams of bananas or 140 grams of apples is the same because the carbs and calories values don't change. That's true. Math is math.

But when it comes to fat loss, math has very little to do with it! Hormones control everything and they even control your attempt to get rid of body fat. By the way, even if the nutrition facts of 100 grams of bananas and 140 grams of apples are practically the same, hormonal responses are not!

The glycemic index is the speed by which the carb enters the bloodstream. You can view the glycemic index of different foods here.

The glycemic index of a carb depends on different factors:


Fiber content
Carbohydrate chemical structure
Fat content
Now you may wonder what the glycemic index has to do with anabolic and defining purposes if the correct daily amount of carbs has been taken in. This is an important key! Maybe the most important.

Click Here To Read More On The GI Index

In the case of a healthy individual, once we open our mouth to eat a food containing carbohydrates, digestive processes begin and that means that hormonal responses begin also. The main hormone responsible for fat accumulation is Insulin, a hormone secreted by the beta cells of the pancreas.

Once a carb has been digested (digested means broken down into its elementary constituents, which is at the end glucose), glucose gets absorbed (absorbed means that it passes into the bloodstream). When glucose reaches the bloodstream it acts as an insulin secreting stimulus, so insulin is secreted and transports glucose into the cells.

To promote anabolic muscle gain or fat loss, the quantity and the speed of insulin secretion is the key that you need to manipulate! The speed and quantity of insulin secretion can make you either more muscular OR fatter depending on the TIME OF DAY at which it is stimulated and if a WORKOUT has been performed.

Time Of Day: If you have studied a little bit of endocrinology, you know that Cortisol is responsible for muscle breakdown. Once the structural protein has been broken into its elementary constituents, amino acids, some of these (the glucogenetic ones) are converted into glucose for energy purposes. So muscle tissue is being sacrificed for energy purposes!

Unfortunately this is a tremendously old law of human nature. Our ancestors didn't have any Cornflakes ready in the kitchen to be consumed for breakfast. Our ancestors had to wake up early in the morning and go hunting to survive. So where did they get the necessary energy for running, climbing, jumping and fighting?

Here's where cortisol comes in. Nature has provided these perfect systems to the human being in order to overwhelm these inconvenient situations. It's what anthropologists call EVOLUTION.

So, why consume a large amount of carbs if an insulogenic effect has already been stimulated by the cortisol-induced glycogenolysis? To make it simple: why eat a large amount of carbs first in the morning if they are still present into the bloodstream because of cortisol incretion?

At this time you may be wondering at what time cortisol is secreted, right? Cortisol follows a nichthemerald rhythm; nichthemerald (nicht translates into night and hemerald into day) means that it is secreted according to a specific rhythm that varies according to the hour of the day or the night.

Its secretion starts at about 4 A.M., reaches its peak at 8-9 a.m and begin to drop right after 12 A.M. If you are having a difficult time getting rid of excess body fat during dieting or if you are more likely to put on fat mass, you should consider this physiological situation induced by evolution and try to limit, but not completely abolish, your carb intake until noon and pay attention to the glycemic index.

Carbs during the night do not promote any fat accumulation. If your total daily carb intake, for example, is 300 grams, then to share them evenly in five meals, each meal would have to contain 60 grams. So if you end up fulfilling your Glycogen stores at dinner (8 P.M.) why should it make you fat?

It's a myth that needs to be erased! But one thing behind the myth is true, but it's physiology! If you consume a meal containing carbs late at night right before going to bed, it won't allow you to get as defined as possible while dieting.

Why? During the very first phases of your sleep a very powerful hormone, GROWTH HORMONE, is secreted from the pituitary gland in bursts. It has a powerful effect on lipolysis and on protein synthesis.

High insulin levels inhibit GH secretion, which is in turn stimulated by high blood glucose levels. In other words GH secretion matches very well with Hypoglycemia during then first phases of sleep! Physiologically speaking, hyperglycemia induces a somatostatinic hypertone. GHRH (growth hormone releasing hormone) stimulates GH secretion, Somatostatin inhibits it!

It's also true that after a person's GROWTH SPURT, a phase where there's a speed up in growth hormone secretion which determines the lengthening in the long bones and goes from the age of 11.7 to 17.5 reaching its peak between the ages of 14 and 15 for the male sex; for females it goes from the age of 9.6 to 14.5 reaching its peak between ages of 12 and 13.

That's why during these ages girls get taller before the boys. GH secretion slows down but it doesn't mean you can't benefit from that little secretion though.

Carbs Consumption After Weight Training:

The major energy source to produce ATP used for performing a hypertrophy-stimulating workout is glucose deriving from glycogenolysis. In order to clarify the reason why carbs are necessary after training and the importance of the quantity of carbs as well as their glycemic index, let's take a closer look to what happens from a physiological point of view.



Weight training for muscle growth is usually structured in 8 to 12 reps for every set. This is also called Anaerobic Training, because it doesn't need oxygen to be carried into the mitochondria to produce energy. In this case, since the use of oxygen isn't possible (remember that oxygen utilization for energy production is possible only when the rhythm of the heart and lungs match each other) the energy stored in the adipocytes as triacylglicerols cannot be used.

The only substrates that can mainly supply energy in the absence of oxygen are the ones stored in the muscles cells, that is the Glycogen and contractile proteins: Actin and Myosin.

Once training has begun, a drop in glucose level occurs which is in turn the key that triggers the signal for glucagon secretion, promoting glycogenolysis and thus promoting more availability for blood glucose that is ready to be used! Adrenaline also affects the glycogen depots resulting thus in a further glycogen depletion.

Unfortunately, muscle protein also gets affected and goes through what is called proteolysis (protein breaks down into amino acids). Once you finish the workout you want to replenish your glycogen depots first and then promote new protein synthesis. This is what everybody aims to achieve, but is also where most of people get lost!

Scientific evidence shows that consuming a blended protein and carb shake right after a workout and another one within two hours from the end of the workout will increase GH and INSULIN levels dramatically! The exact macronutrients doses should be 0.5 grams of protein per kg of Fat Free Mass (FFM) and 1.5 grams of carbs per kg of FFM.


Protein & Carbs Needed After A Workout?

Enter Your Bodyweight In The Appropriate Box Below:

Your Bodyweight In Pounds: OR In Kilograms:

Your BodyFat Percentage: % (Do not enter the percent sign.)



The type of macronutrients is very crucial too. You need to consume very fast acting macronutrients like GLUCOSE as the carbohydrate source and Whey Protein Isolate as the protein source.

You should use GLUCOSE because it's has the highest glycemic index and therefore it has the ability to enter the system faster than another other type of carb, which then promotes a rapid glycogen replenishment through high insulin secretion. High insulin levels in this particular post-training time not only promotes glycogen replenishment but also act as a cortisol blocker. Cortisol is extremely high after an intense workout because of its stressor-secreting stimulus, which is the weight training itself.

For your protein source you should use Whey protein isolate because it also enters the system in a very fast way, and is then available to promote structural muscle protein turnover and thus new protein synthesis.

After my first article "How To Get Ripped Using Science", many people asked me what a post workout meal should consist of!

Let's suppose you weigh 80 Kg and your FFM is 75 Kg.

Following the instructions above you should consume:

75Kg X 1.5 grams of carbs = 112.5 grams of carbs;
75Kg X 0.5 grams of proteins = 37.5 grams of proteins;

Therefore, mix together 112 grams of glucose with 42 grams of whey proteins isolate. (42 grams of protein if the proteins you are using is 90%, otherwise make the right adjustments. In fact 42 X .9 = 37.8 grams of protein).

If you don't have glucose, you can use another high glycemic index source of carbohydrates. Remember though that glucose after a seriously hard hypertrophy stimulating workout does the job like no other carb! Just check their % carbs values and make adjustments in order to satisfy your personal post-workout carbohydrate requirements.

Consuming other sources either for carbohydrate and protein won't be of aid. In fact a slower protein and/or a lower glycemic index carbohydrate won't be able to lead to a fast recovery and protein turnover, nor will it be able to block the harsh cortisol secretion immediately. This translates into a further prolonged catabolic state.

If you worry that the high insulin level could promote the storage of glucose into the adipocytes, this is not that case. When your glycogen depots are really depleted after an intense lactic acid anaerobic exercise like weight training (8-12 reps to failureusing the maximum weights to perform this range of reps), all the glucose will be carried into the muscles and liver cells.

Use science to reach your best shape!