Protein |
Protein Protein – The Basics
Of the three macronutrients, protein is the most critical for bodybuilders. Protein is responsible for growth, maintenance, and repair of muscle tissue, which is why top bodybuilders constantly monitor their protein intake.
Muscle is primarily composed of protein (about 22 percent) and water (about 70 percent). The remaining percentage of muscle composition is glycogen, fat, vitamins, and minerals. Similar to fat and carbohydrate, protein is made up of carbon, hydrogen, and oxygen. But, unlike fat and carbohydrate, protein contains nitrogen. This molecular difference gives an indication of the metabolic state of muscle tissue.
Good Protein Sources |
Daily Protein Requirements
In general, a bodybuilder needs twice as much protein as the average person.
Researchers have determined that a person trying to build muscle needs between 1.5 and 2 grams of protein per kilogram of body weight each day. This means for an 80 kg man, he should be taking in a minimum of 120-160 g of protein per day.
Additionally, the type of training and the amount of muscle fibers stimulated during training may influence protein requirements, with higher amounts of protein required when training stimulates a larger amount of muscle fibers.
Good Protein Sources
It is essential that you not only have an adequate intake of protein, but also that you have it at regular intervals, and from the right sources, to make sure that you aren’t deficient at any point during the day or the night.
The best sources of protein are eggs, fish, poultry (turkey and chicken), meat, cottage cheese and dairy products—the animal proteins. Plant proteins—from foods like rice, beans, corn, peas, and nuts—are not as easily assimilated into the body as animal proteins.
The Benefits of Protein
Ten effects of protein:
- Acts as a source of energy when carbs are not available
- Helps the body burn fat for fuel
- Preserves muscle tissue during dieting or cutting
- Builds and maintains hormone levels
- Keeps pH levels balanced
- Regulates the balance of fluid in the body
- Keeps the body’s immune system functioning properly
- Boosts metabolism
- Regulates growth hormone levels
- Helps lower insulin levels in the blood
Animal Protein vs. Vegetable Protein
Meat is a complete protein, that is, it contains all the amino acids—the building blocks of protein. By contrast, vegetables, nuts, and fruits lack one or more of the essential amino acids and are considered incomplete proteins. Therefore, a person would have to eat a wide range and larger amounts of plant protein foods to get the same benefit that a small serving of meat would provide.
Protein Supplements
Unlike some nutrients, protein cannot be stored in the body. Instead, it must be taken in continually to be useful— this is another reason to eat frequently.
In order to get enough protein, most bodybuilders take protein supplements, usually in powder form and mixed with juice, milk, or water. Most of today’s supplements have little or no fat and taste much better than the supplements of the past. You don’t have to hold your nose to force down a protein drink anymore. Protein supplements are handy because they’re much easier to prepare and consume than a full meal—while providing most of the same nutrients.
Protein supplements are usually made from whey, egg whites, soy, or milk.
High Protein Diet And Kidney Health
Is too much protein dangerous? Fact is that there are no studies that have ever shown a high protein diet causing kidney damage in persons with normal kidney function. Only people who already have a pre-existing kidney condition need to be concerned with keeping their protein in check.
While it is true that people with kidney problems generally need to follow a special diet that is lower in protein, this doesn’t mean that eating protein caused the kidney problems to begin with.
To give you an example, let’s look at a similar situation. Diabetics generally need to be put on a special diet that controls their carbohydrate intake. However, eating carbohydrates does not directly cause diabetes.
When your body is healthy and functioning properly you can safely consume and utilize protein, carbohydrates, and fats.
Biological Value of a Protein
Proteins are rated by their biological value as complete (high biological value) or incomplete (low biological value) depending on whether or not they contain all of the essential amino acids. Typically, proteins from animal sources (eggs, meat, fish) contain all of the essential amino acids and are thus considered complete. Proteins in grain and vegetable products do not contain all of the amino acids and are considered incomplete.
High-protein diet |
Protein Consumption and Muscle Building
Any bodybuilder with a rudimentary understanding of the sport would know the key to gaining muscle is protein consumption. Granted, training, rest and other nutrients all enhance anabolism, and growth, but protein (being the key size-building nutrient) is absolutely essential when it comes to packing it on – 60-70% of bodily protein is found in muscle.
In fact, protein is the key “building” nutrient for a variety of bodily tissues, many of which support muscle growth (enzymes, skin, hair, nails, bones, and connective tissue are all constructed from protein). Protein makes up 15-20% of ones bodyweight and is thus, next to water, the body’s second most abundant substance.
Nitrogen Balance
Nitrogen is a compound unique to protein that can provide a direct measure of ones amino acid (protein) status. All macronutrients (protein, carbohydrates and fats) contain carbon, hydrogen and oxygen. Among these, only protein contains the additional nitrogen molecule. Therefore, nitrogen excretion (meaning the amount of protein being eliminated from the body) can be measured to determine the amount of protein present in the body, and given up to 70% of protein is found in muscle tissue, this gives an excellent indication of the body’s muscle building potential.
Nitrogen balance is considered the difference between the amount of nitrogen taken in and the amount excreted or lost. When nitrogen supplies do not meet the nitrogen demands, protein tissue is broken down because of catabolism, and nitrogen is lost in the urine (negative nitrogen balance). If more nitrogen is consumed than excreted, you will be in an anabolic or muscle-building state (positive nitrogen balance).
High-Protein Diet for Weight Loss
If you’re trying to lose weight via serious strength training, you may need to take in more than the recommended upper limit of protein while cutting back on fat or carbohydrate. Without extra protein, your body could lose muscle mass along with fat, and lost muscle means a slower metabolism. A slower metabolism means your weight loss stalls and you regain weight faster.
Second, protein creates a high level of satiety, both during meals and between them. In other words, it makes you feel fuller faster and keeps you feeling full longer between meals. Once more, this is a great tool for weight loss but perhaps not advisable when you’re trying to gain. (This effect does wear off as you get used to a higher-protein diet, however, so it may not affect long-term weight gain or weight loss.)
Are Proteins a Good Source of Energy?
Although protein contains about 4 calories per gram of energy, it is not typically considered a primary energy source like carbohydrate and fat. The amino acids, especially the essential amino acids supplied by dietary protein, allow the body to synthesize the proteins it needs for tissues, hormones, and enzymes. In addition, protein is inefficient at providing energy. Protein has a high thermic effect, meaning that for the amount of calories provided per gram of protein (compared to fat or carbohydrate), much of the energy is used for metabolic processes, resulting in a lower energy density.
The Timing of Protein Intake
Ingesting amino acids through food or supplements before and after exercise stimulates amino acids being transported into skeletal muscle, and therefore, stimulates protein synthesis.
Some evidence suggests that consuming amino acids immediately before resistance exercise increases protein synthesis to an even greater extent than consuming them after training. This is possibly because of the increased blood flow to muscle that occurs during training, which then results in increased delivery of amino acid to the muscles.
Muscle anabolism occurs whether amino acids are consumed alone or carbohydrate is consumed alone at one and two hours after exercise. However, the greatest anabolic effect is apparent when amino acids and carbohydrate are combined.
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