Bodybuilding Nutrition

The Science of What You Eat

If you’ve studied Biology or Dietetics then you should have a fairly good idea of the roles of various food stuffs in our diet, if you were an A-grade student you may even recall the five major food groups. For those of you more prone to chatting at the back here they are again: carbs, protein, dairy, fruit and vegetables and fats. Handily that’s also arranged in order of recommended quality (I’m clever like that) so you need lots of carbs in order to function properly and few fats.
Essentially these food groups can be categorised into those used by the body as fuel (those used in metabolic functions) and those used by your body to build and repair (those used in anabolic functions). Obviously for bodybuilding both are highly crucial; you use the energy to go and lift stuff at the gym and then you use the building blocks to build back the ‘microtears’ you cause in the gym (more on that later). In the latter case you literally are what you eat. I’m a giant tuna pretty much then… When it comes to energy and building blocks what we’re really talking about are the carbohydrates and the protein. Bellow I’ll explain how these work and why need to include them in your diet. I’ll warn you though; this will probably get quite technical so bear with me. If you’re not interested in how or why protein and carbs work then feel free to skip the next couple of segments. I don’t recommend this however as it’s very useful to understand the science what you do and is just one factor that can set you apart from the competition. At the same time it’s quite interesting; we should all know what our own bodies are made of.

Carbs and Sources of Energy

Carbs work as little fuel cells for our body which when used immediately do not turn into fat. Some bodybuilders make the mistake of ironing carbs out of their diet in order to ensure they don’t gain any weight that isn’t muscle. However this basically means they’re running on empty which can be dangerous and will damage their performance in the gym. We are designed pretty well, either through God or evolution depending on which belief system you subscribe to, and everything we eat we eat for a reason. Cutting anything out of your diet is a mistake and whatever the current trends in bodybuilding nutrition may say, they almost always come back full circle and realise that straying to far from the tried and tested formula is a mistake.
Essentially our muscles get their energy from splitting Adenosine Triphosphate (also known as ATP, an adenine nucleotide bound to three phosphates), the 'global energy currency'. ATP is produced in the mitochondria of cells from the glucose in our diet and energy can be released through the breaking of the high-energy bonds that hold the phosphates together. This creates Adenosine Diphosphate or Andenosine Monophosphate with two or one phosphates respectively as a biproduct.
Creatine phosphate is used to maintain the levels of ATP in our muscles by converting used ADP or AMP back into ATP using its own high-energy phosphate bond. This supplies our muscles with energy during fast usage such as during sprinting (the phosphogen system). Our muscles can only retain enough ATP for roughly three seconds of use at full power however and can store around 2-3 times more creatine phosphate; allowing for 8-10 seconds of maximum exertion in total. This method of obtaining energy is called the Phosphogen System and is the system used for short explosive moves.
Now crucially, ATP can also be obtained from glycogen – found in most carbohydrates. This is a slightly slower process, known as the Glycogen Lactic Acid System, where glycogen stored in the muscles is split into glucose which is then split again to release four ATP molecules providing approximately an additional one and a half minutes of extra energy, though at lower power and resulting in the by-product lactic acid. This process is used in swimming or the one to four hundred metre sprint and is 'anaerobic', meaning that it does not use oxygen, or for us bodybuilders maybe a set of one hundred sit ups.
The last line of defence against... extreme tiredness, The Aerobic System, kicks in when energy is needed for extended use. It achieves this through the oxidisation of foodstuffs in our mitochondria, in other words by 'burning' carbohydrates (initially), then fats and finally protein to get ATP. This is another reason bodybuilders shouldn’t completely neglect Carbohydrates (or engage in excessive CV) in their diet lest they risk cannibalising their protein. For these reasons The Aerobic System can sustain an athlete for two hours or longer in some cases and has water and carbon dioxide as a by-product as opposed to lactic acid. Additionally, in order to provide muscles with adequate oxygen, the body pumps blood to them (which creates the feeling of being 'pumped' in the gym), diverting it from the rest of the body and other organs organs so increasing the depth and rate of your breathing. These three systems kick in in the above sequence, starting with the Phosphogen System, then the Glycogen Lactic Acid System and finally the Aerobic System. All three will likely be used during a workout which is why eating carbohydrates for energy is so important.
Making matters more complicated is the fact that there are two types of carb: complex and simple. The distinction is made by the number of sugar units in the food where foods with just one or two are simple (monosaccharides and disaccharides respectively) and those with longer chains are complex. Sugar and sweet foods are examples of simple carbohydrates while starches such as bread and pasta are examples of complex carbohydrates.
Here it’s the complex that we’re interested, so bread, pasta and bananas; I’m afraid sugar and cake are out for now as they’ll give you an energy spike followed by a dip and are too easily converted into fat. Bread , rice, pasta, or a banana, eaten an hour or so before a workout then can give you a more steady and long lasting energy supply. That said sports drinks such as Lucozade or certain supplements can be a good way to get an energy rush from simple carbohydrates and sugars. Again, nothing should be completely left out of your diet.

Protein and the Building Blocks of Life

The above description of how the body utilises carbohydrates and ATP for energy is known as ‘catabolism’. At the other end of the spectrum is ‘anabolism’ which is where the body repairs and maintains itself using amino acids (the building blocks of life) found in protein.
The protein in our protoplasm is the most abundant substance making up 10-20% of our cells’ mass. This is then used for structure, maintaining the form of the cell; and for enzymes which control chemical reactions within cells. Essentially when you eat meat you’re almost ‘recycling’ the animal and using it to repair and build your own body. Each cell has within it your genetic code – your DNA – and it uses this as a guide for sending the amino acids where they’re needed in the body. This is why a supply of high-quality protein is so important for the body and particular for aiding in recovery and growth after a workout.
Muscle fibres cannot reproduce via mitosis (by splitting in half) as they have multiple nuclei. This means that in order for your muscles to grow, the existing fibres need to become thicker. For this to happen the muscle must add more ‘myofibrils’ (the small ‘strands’ which make up muscle fibres and that are themselves composed of even smaller sarcomeres) which it does by splitting them along their longitudinal axis. This action however requires lots of Myosin, Actin and other proteins (and how much protein a muscle fibre can use is limited by the number of nuclei in each one).
When you strain a muscle from ‘overloading’, probably by hoisting a hefty great dumbbell, you’re creating 'microtears' in the fibres. Though that sounds gruesome don't worry - this is how hypertrophy (muscle growth) occurs. Once the fibre is recognised as damaged 'satellite cells' (AKA stem cells that wait in the area ready to jump to action) will be sent to the area in order to repair the damage, the single nuclei of the satellite cells however will stick around and become incorporated into the repaired fibre meaning that it has more nuclei than it did before and can use more proteins to become thicker. This also explains why the bigger you are the more protein you need.
So it’s important we get lots of protein and the official line for bodybuilders is that they should be eating around one gram of protein for every pound of weight. So if you weigh in at 200 pounds you need 200 grams of protein. If you weigh 175 pounds you need 175 grams of protein… I could go on but you should get the idea. What’s also important though, is that we consume high quality protein and that we get all 22 amino acids; though this number can range from 20 to 26 depending on the source, it really comes down to a matter of definition and for bodybuilders it is the 22 that are crucial for muscle synthesis. These are as follows: alanine, arginine, asparagine, aspartic acid, cysteine, cystine, glutamic acis, glutamine, histidine, isoleucine, leucine, lysine, methionine, ornithine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine. Yup, they sound like names from a sci-fi film (I love ‘phenylalanine’). The reason it’s essential to get all 22 is that if your body needs an amino acid and cannot get it from your diet, it may break down muscle in order to obtain it (known as ‘negative nitrogen balance’). As well as aiding with muscle growth and maintenance they also have many other benefits and are important for every aspect of our health.
However very few sources contain all 22 with most meat containing 19 or less, even the wondrous ‘Whey’ (of whey protein fame) is missing two. This is why it’s essential to make sure you consume more than one type of protein in day and preferably at each sitting. In other words don’t just eat chicken as your protein source if you want to grow. Preferably you should try and get more than one protein source at each sitting as you cannot supply an amino acid after it is too late. Eggs fortunately do contain all 22 due to the combination of the egg and the yolk, which is why removing the yolk to eliminate fat (as many bodybuilders do) is a mistake.
The quality of a protein source is also measured by its biological value and absorption rate. These numbers indicate how much of the protein you consume can actually be utilised by the body. For example, while eggs have a BV of 100 and an AR of 94%, tuna has a BV and AR of around 70% and 80% respectively. Therefore if you ate the same amount (in grams) of protein from tuna and eggs, you’d benefit most greatly from the eggs (though both are very good). Also key to be aware of is how much fat a protein source contains which is another reason to go for fish or white meat over red meat. A list of suggested protein sources with their statistics will be presented later in this book.
So you need to consider several factors when consuming your protein: how many grams your getting, how much of it your body can utilise and how much fat is in it. You then need to pick at least two to combine at each sitting.

The Other Food Groups

I’ve already mentioned several times at this point how important it is not to eliminate entire food groups from your diet (that’s right, even fat). Here’s what the others do for you, how they work, how to consume them and why you need them. Fat is the black sheep of the food groups’ flock and is feared by bodybuilders and dieters alike. When our bodies have excess carbs they sensibly convert them into fat cells to be stored for future use, this process ironically takes a large amount of energy itself however meaning that only a proportion of the unused carbohydrate is stored at all. The problem is however that other animals also use the same process meaning that when we eat meat we are often also eating their fat cells which take very little energy to convert. These cells then are immediately packed on as fat resulting in a layer of fat cells that prevents definition in the muscles and eventually leads to a bulging gut and flabby arms – however strong you are underneath no one is going to know.
This does not mean however that you should completely eliminate fat from your diet. Firstly, you never know when you might actually need to burn that extra fat and if you don’t have any your body will burn your muscle instead – essentially cannibalising itself to get the energy it needs. Secondly, essential fatty acids have many other uses including strengthening cell membranes, lowering blood cholesterol (which will be high in a high protein diet), helping to repair wounds, aiding in blood clotting and regulating blood pressure. A deficiency can result in bad skin, dull hair, delayed wound healing, thirst and even heart disease and arthritis in extreme cases. Crucially fat is also needed for the absorption of protein. So don’t completely rule it out!
Fat has only become a problem from around the 20th century where large amounts of fat are used in all sorts of cooking and deserts. Eating roughly the amount of fat you’d expect to find in the wild then won’t hurt, just limit lard and cakes etc. The aim then is to eat minimal extra fat that isn’t from your protein or carbohydrate sources, not to eliminate it completely.
Vitamins, minerals and fibre are also vital for bodybuilding though the link may not seem obvious immediately. The point here is that if you restrict your diet to just chicken, eggs and rice, not only will it be bland but you won’t be getting any fibre, vitamins, minerals or fats. At first you’ll quickly pack on lean muscle but soon you’ll find yourself encountering other problems. For example your immune system will be week from lack of vitamins so you’ll have frequent colds, each of which will keep you out of the gym for a week and set you back considerably. You’ll also be prone to injury with weak bones due to a lack of calcium and let’s just say you might be spending a long time on the toilet too… You could easily have added steamed veg and perhaps a nutritious cereal with skimmed milk and you’d have a far tastier diet that would be much better for your health and your success in the gym.
In other words you should include as wide a variety of foods as possible while still being selective and it’ll be easier to stick to this way too. Your body knows what it needs so listen to its cravings, just try and interpret them with a healthy slant.