» Section 1:
Intro & The History Of Protein.
» Section 2: Protein & The Amino Acid Connection.
» Section 3: Benefits Of Protein For Athletes.
» Section 4: Comparing Different Protein Sources.
» Section 5: Building Muscle Using Protein.
» Section 6: The Value Of Protein Supplements.
» Section 7: Protein Supplements & Protein Food Sources.
» Section 8: Protein Timing For The Bodybuilder.
» Section 9: Conclusion.
» Section 10: Final Quiz.
3. Benefits Of Protein For Athletes.
Protein is the only nutrient directly responsible for building muscle. By being a direct precursor to building muscle protein is essential for muscle recovery and growth. To build muscle it is essential that proper amounts of high quality protein be consumed at the proper times.
Protein, whether from your own tissues (e.g. muscle) or from food, consists of amino acids linked together in chains. Amino acids are the principle means by which we humans get nitrogen, for growth.
Maintaining An Anabolic State:
Because athletes and bodybuilders work out often, protein levels become depleted. By eating frequent high quality protein meals you can keep your body in an anabolic state and develop lean muscle mass.
Raises Growth Hormone and Insulin-like Growth Factor-I (IGF-1) Levels:
Growth hormone increases calcium retention, strengthens and increases the mineralization of bone, increases muscle mass and induces protein synthesis and growth of many different organ systems of the body, resulting in a "positive nitrogen balance."
Growth hormone enhances the utilization of fat by stimulating triglyceride breakdown and oxidation in adipocytes, promoting lipolysis, which results in some reduction of adipose tissue (body fat) and rising amounts of free fatty acids and glycerol in the blood.
Growth hormone also reduces liver uptake of glucose, an effect that opposes that of insulin.
Last but certainly not least, a major role of growth hormone which is of extreme importance to the bodybuilder is stimulating the liver and other tissues to secrete insulin-like growth factor-I (IGF-1), a hormone homologous to proinsulin.
IGF-I (originally called somatomedin C) is the primary protein involved in responses of cells to growth hormone. IGF-I is the key player in muscle growth stimulating amino acid uptake and protein synthesis in muscle and other tissues leading to increased growth.
Growth hormone is a protein hormone of about 190 amino acids that is a major participant in control of several complex physiologic processes, including growth and metabolism.
Inhibitors of growth hormone secretion include dietary carbohydrate and glucocorticoids. Stimulators of growth hormone release include (among others) sleep, exercise, hypoglycemia, and dietary protein. Therefore, increased protein consumption can increase growth hormone release.
| What Is Hypoglycemia?
Hypoglycemia means low blood sugar (glucose). Hypoglycemia causes the body to release adrenaline. The adrenaline functions to restore and maintain blood glucose levels by mobilizing stored glycogen and fat, converting them into glucose. In turn, the released adrenaline causes symptoms of nervous system stimulation, such as anxiety, sweating, tremor, palpitations, nausea and pallor. Hypoglycemia also starves the brain of glucose energy, which is essential for proper brain function. Lack of glucose energy to the brain can cause symptoms ranging from headache, mild confusion, and abnormal behavior, to loss of consciousness, seizure and coma. Severe hypoglycemia can cause death.
Additionally, increased protein consumption (or substituting carbohydrates for protein can help control blood insulin, a favorable environment for the release of growth hormone, also known as somatotropin. Protein consumption has also been shown to increase the insulin-like growth factor 1 (IGF-1) response to both exercise and eating.
Increasing Thermic Levels:
Protein has the highest "thermal effect" of any food. That means that foods that are high in protein can actually speed up your metabolism as much as 30% because your body has to work harder to digest process and utilize it compared to foods that are higher in fat or carbohydrate.
For instance a 125-gram portion of chicken breast (about 2 pieces with 24 grams of protein and 1.5 grams of fat) may in fact be calculated at approximately 90 calories due to the energy expenditure during the thermic digestive process.
There are several studies that support this, dating back to 1990. For instance Robinson et al3 looked at protein turnover and thermogenesis in response to high-protein and high-carbohydrate feeding in men. In this study a group of seven men received hourly isocaloric meals of high-protein or high-carbohydrate content.
Their responses to feeding were compared with those to a short period of fasting. The 9-hour thermic response to the repeated feeding of high-protein meals was found to be significantly greater than that to the high-carbohydrate meals and the rate of whole-body nitrogen turnover over 9 hours also increased, especially within the high-protein fed group.
This study and studies like it support that the "thermal" effect of protein is one of the primary reasons that a higher protein diet is more effective for fat loss than a high fat diet or a high carbohydrate diet. It must be noted however, that this effect is only obtained through whole food sources and not through pre-digested protein supplements.
Increased Fat Mobilization:
Protein consumption also increases plasma concentrations of the hormone glucagon. Glucagon is responsible for antagonizing the effects of insulin in adipose tissue.
Increased levels glucagon leads to greater fat mobilization while also decreasing the amounts and activities of the enzymes responsible for making and storing fat in adipose and liver cells. By lowering these "fat enzymes" studies have shown that there is greater fat loss during dieting activities and less fat storage when eating excess calories.
Another interesting effect of increasing protein consumption is an increase in satiety levels. People on higher protein diets felt fuller at the same calorie intake. High-protein foods slow the movement of food from the stomach to the intestine. Slower stomach emptying means you feel full for longer and get hungrier later. Slowing carbohydrate digestion also slows insulin release, which is a favorable environment for growth hormone release.
Lowers Blood Insulin Levels:
Consuming protein with carbohydrates slows down the insulin response. This is extremely important in controlling energy levels, and is equally important when trying to develop a leaner physique. Large concentrations of insulin in the bloodstream activate fat storage enzymes and promote the movement of triglycerides in the bloodstream into fat cells for storage and inhibit enzymes that promote the breakdown of stored body fat.
Controlling the insulin response is also important because it also reduces the potential for insulin resistance, a condition in which people lose their sensitivity to insulin. Studies have shown that excess blood sugar, and hyperinsulinemia is associated with a host of diseases such as diabetes, high cholesterol, high blood pressure, heart disease and cancer.
Take Protein Quiz #3!