Overview of Protein: Understanding Protein and the Role it Plays in your Training

Posted: Tuesday, 17 April 2012 by Strength&Nutrition24/7 in Labels:

  1. Intro
  2. Essentials of protein
  3. Protein digestion
  4. Protein quality and methods of assessment
  5. Nitrogen balance
  6. Protein Requirements
  7. Protein timing
  8. Protein Sources
  9. Protein type
  10. Conclusion
  11. References


For over 150 years, scientists have been exploring the role that protein plays in human anatomy and physiology. In the realm of sport and exercise nutrition, there is no topic that has received more attention or heated debate then protein (Antonio, 2007). It was first hypothesized in the mid 1800s by a man named Von Leibig that protein was the main source of fuel for muscular contractions (Von Leibig, 1842). However, this was later disproved in 1925; which lead most scientists to believe that protein needs were not affected by exercise (Cathcart, 1925). Shockingly, it has only been in the last 40 years that research has come to a middle ground in terms of protein as a source of energy. In general, protein is not a major fuel source for muscular contractions, but in certain circumstances protein and/or amino acids can play an important role in muscle metabolism and exercise performance (Antonio, 2007).

Essentials of protein
Protein, fat, and carbohydrates make up the “big three” (macronutrients) (Powers, 2007; Tortora, 2009; Antonio, 2007). Of these three, only fat and protein are essential nutrients (Powers, 2007; Tortora, 2009; Antonio, 2007).  Protein and carbohydrates are similar in the fact that they both have an energy density of four Kcals per gram (Powers, 2007; Tortora, 2009; Antonio, 2007). However, protein differs from carbohydrates and fats by the nitrogen atoms. The nitrogen atoms in protein are what give the name amino (nitrogen containing) to the amino acids (Powers, 2007; Tortora, 2009; Antonio, 2007). Protein contains the nine essential amino acids (Powers, 2007). Without these amino acids, the body cannot synthesize all the proteins needed for tissues, enzymes, and hormones (Powers, 2007; Tom, 2009). The body synthesizes the various proteins through numerous combinations of amino acids linked together by peptide bonds (Powers, 2007; Tortora, 2009; Antonio, 2007). In general, the body’s proteins are polypeptides that contain over 100 amino acids linked together (Antonio, 2007).
Amino Acids

  • Histidine
  • Isoleucine*
  • Leusine*
  • Lysine
  • Methionine
  • Phenylalanine
  • Threonine
  • Tryptophan
  • Valine*

  • Alanine
  • Arginine†
  • Asparagine
  • Aspartic acid
  • Cysteine†
  • Glutamic acid
  • Glutamine†
  • Glycine†
  • Proline†
  • Serine
  • Tyrosine†

*Branched chain amino acid
†Conditionally essential amino acid

A good illustration to understand the difference between essential and non essential macrontruients is to illustrate two islands with people stranded on each. On the first island, there is only carbohydrates, while on the second there are only fats and protein (this is impossible of course, but humor me for the sake of the illustration). In the first few days, people on both islands are feeling alright. This indicates they have no problems. However, if we came back to the islands a month or two later, the people on the carbohydrate only island would all be dead, and the people on the protein and fat only island would be fine, perhaps sluggish and tired.

Protein digestion
The process of protein digestion begins in the stomach. In the stomach, the proenzyme pepsinogen is converted into pepsin by hydrochloric acid (Tortora, 2009; Antonio, 2007). Pepsin works to fragment protein into smaller peptides and free amino acids by cleaving the peptide bonds that link amino acids together (Tortora, 2009; Antonio, 2007). Following the digestion in the stomach, the gastric juices enter into the small intestine where the pancreatic juices (trypsin, chrymotrypsin, carboxypeptidase, and elastase) and the brushborder itself (aminopeptidases, intracellular peptidases) complete the cleavage of the peptide bonds to produce absorbable amino acids (Tortora, 2009; Antonio, 2007). The absorbable amino acids are then absorbed from the lumen of the small intestine into the blood by either cotransporter or facilitated diffusion (Tortora, 2009; Antonio, 2007). The protein that is not absorbed is converted mostly to methane (Tortora, 2009; Antonio, 2007). Thus, further research has not found a maximum amount of protein that can be absorbed in a meal (Tortora, 2009; Antonio, 2007). However, the scientific community generally agrees that humans are capable of absorbing approximately 95% of animal protein and 85% of plant protein (Young, 1994).

The amino acids that have been absorbed into the bloodstream join the amino acid pools. The amino acids are now capable of being used to synthesize proteins and other nitrogen compounds, oxidized for energy, or excreted in the urine. During bouts of exercise, amino acids are often oxidized, particularly BCAAs (leucine, isoleucine, valine) which are used in significant amounts. In order for the amino acids to be oxidized, they must go through one of two processes: 1) transamination or 2) oxidative deamination.

Note: Protein that is not absorbed is mostly turned into methane; amino acids that are not used are excreted in urine. Therefore, protein in excess is not stored, unlike carbohydrates and fat. 

Protein quality and methods of assessment

The quality of the protein you consume is very important to consider when improving your health and performance. Protein quality is the ability of a dietary protein to support one biological growth and maintenance (Schaafsma, 2005). Protein quality is most commonly measured by three methods:

  1. Biological value (BV)The purpose of BV is to measure the amount of nitrogen retained in comparison to the amount absorbed (Antonio, 2007). The values of different food proteins are determined through experimentation on humans and laboratory animals (Antonio, 2007). It is extremely difficult to determine nitrogen retention; in fact it is so difficult to determine that research has historically over estimated nitrogen retention in humans. Even with the difficulties involved with this assessment method, it is still considered a valid form of assessing protein quality (Fuller, 1994)
  2. Protein efficiency ratio (PER)The purpose of PER is to measure its ability to support the growth and weaning of rats. This method looks at the amount of weight gained over the amount of protein consumed (Antonio, 2007). This is a less ideal form of measuring protein quality since it looks at rats and not humans. Further, the assessment does not attempt to assess what is needed for an adult to maintain health.
  3. Protein digestibility-corrected amino acid score (PDCAAS) This method is relatively new and a very effective way of measuring protein quality. Its purpose is to assess protein quality for children older than one and non pregnant adults (Antonio, 2007). This is assessed by comparing the amino acid profile of a specific dietary protein against the essential human amino acid requirements that have been determined by the Food and Agriculture Organization (Antonio, 2007). This is then corrected by taking the digestibility differences into consideration (Antonio, 2007). The dietary protein is then given a rating between 0-1, with 1 meaning that the protein exceeds the dietary needs of the body (Antonio, 2007). The down side of this assessment is the cost, which has stopped this from being used in nutritional facts thus far.

Figure 1

Nitrogen balance
The amount of protein to be consumed by general public and athletes has been generally determined by nitrogen balance studies. The liver, skeletal muscles, and blood make up the amino acid pools of the body. When the amount of nitrogen enters these pools at the rate it excretes the body, it is at equilibrium (nitrogen balance). The body is in a constant battle to maintain the nitrogen balance. In general, periods of overtraining and fasting equates to a greater loss of nitrogen then intake and a state of negative nitrogen balance takes place. However, when lean body tissues are in a state of hypertrophy the opposite occurs (positive nitrogen balance). This is generally measured by nitrogen intake from food versus nitrogen output in urine, sweat, and feces. This form of study is simple to understand, but is very difficult to perform and have historically overestimated nitrogen retention in humans (Fuller, 1994).

Protein Requirements
Athletes who participate in intense training have been found to require a higher dietary protein need than individuals who do not train (Kerksick, 2006; Kreider, 1999; Lemon, 1992; Maclean, 1993; Lemon, 1997; Lemon, 2000; Tipton, 2004; & Tarnopolsky, 1992). However, not all research agrees with the findings that physically active individuals require a greater amount of protein than the current suggestions (Rennie, 2000). Many factors may also play a role in the amount of protein required, such as, energy intake, exercise intensity, exercise duration, training status, and gender (Lemon, 1997; Lemon, 2000; Tipton, 2004; Rennie, 2000; Lemon 1991; Lemon, & Proctor, 1991; Rankin, 1999; Tranopolsky, 2004; & Lambert, 2004). With this in mind, and understanding that protein intake for optimal health/performance is yet unclear; below is a list of the current RDA recommendations for protein intake for sedentary adults, along with values for different forms and statuses of exercise.
Table acquired from Antonio, 2007
Activity Level g/kg body weight

  • Sedentary 0.8 (0.4g/lb)
  • Recreational exerciser 1.0-1.4 (0.5-0.7g/lb)
  • Wt training (maintenance) 1.2-1.4 (0.6-0.7g/lb)
  • Wt training (muscle gain) 1.4-1.8 (0.7-0.9g/lb)
  • Endurance training 1.2-1.4 (0.6-0.7g/lb)
  • HIIT 1.2-1.8 (0.6-09g/lb)
  • Weight-restricted sports 1.4-2.0 (0.7-1g/lb)

Teens are recommended to take an additional 10%

Protein timing
When considering the nitrogen balance concept, we see that when the balance is positive, skeletal muscle mass will increase (Tang, 2009; Fry, 2009; Kraemer, 2002; Kraemer, 1998; & Hulmi, 2010). Conversely, a negative nitrogen balance involves a reduction in skeletal muscle mass (Tang, 2009; & Hulmi, 2010). It has been clearly demonstrated that acute bouts of heavy resistance exercise and/or intermittent exercise of repeated short and high intensity bouts significantly raises the body’s ability to synthesise muscle protein (Tang, 2009; Hulmi, 2010; American, 2009). However, nitrogen balance remains in the negative because muscle protein breakdown occurs at an even greater rate in a fasted state (Biolo, 1995; Tipton, 1999; Pitkänen, 2003).  This can be avoided by the ingestion of protein or essential amino acids pre and/or post training, and produces a positive nitrogen balance (Tipton, 1999; Tipton, 2007; Wilkinson, 2007; Koopman, 2005; Tang, 2007; Moore, 2009; Katasanos, 2008; Ivy, 2004; & Tang, 2009). By creating a positive nitrogen balance through ingestion of protein and essential amino acids, pre and/or post exercise can enhance hypertrophy in response to chronic resistance training (Andersen, 2005; Bird, 2006; Cribb, 2007; Hartman, 2007; Burke, 2001; Candow, 2006; Kerksick, 2006; Willoughby, 2007; & Hulmi, 2009). Hypertrophy can be further enhanced by ingesting protein and essential amino acids within an hour of training (Esmarack, 2001; Cribb, 2006). A multitude of studies have demonstrated that there is a two hour window of opportunity, post exercise (Ivy, 2004; Ivy, 1988; Esmarack, 2001; Anderson, 2005;  & Levebhagen, 2001). After a mere 45 minutes, this window already begins to close. During this time, your muscles are extremely insulin receptive. In the 45 minutes of high insulin sensitivity, the body is in a state in which it can stimulate glucose storage and protein synthesis. Because of this ability, insulin has earned the title “anabolic regulator of the muscle.” Due to this, insulin may in fact, be the most important hormone to increase muscle strength and mass (Ivy, 2004). This 45 minute window is incredibly significant, if you ingest high glycemic carbohydrates and protein during it, you can reduce your recovery time by 16-24 hours (Ivy 2004).  

Figure 2

A study completed by Anderson in 2005 looked at the effect resistance training and combined with timed ingestion of protein on muscle size and strength. The study found that young men who supplemented with 25g of protein before and after training had an 18-26% greater increase in muscle hypertrophy than men who consumed 25g of high glycemic carbohydrate pre and post exercise. Another study completed by Roy was the influence of post-exercise macronutrient intake on energy balance and protein metabolism in active females, participating in endurance training. It is found that, women who were performing a 7 day intense cycling exercise program, had a reduced body weight loss and improved nitrogen status when post exercise macronutrient supplementation took place. Research has further demonstrated greater insulin response and glycogen synthesis when protein and carbohydrates are ingested together, rather than carbohydrates alone (Ivy, 2002; Zawadzki, 1992; & Williams, 2003).  However, it is interesting to note when a high amount of carbohydrates are ingested in the immediate 4 hours because after exercise, little added benefit occurs (further supporting the 2 hour window) (Carrithers, 2000;&  Jentjens, 2001). It has also been found that the ingestion of protein, amino acids, and carbohydrate causes greater increase in muscle protein synthesis than carbohydrate and protein alone (Borsheim, 2004). It has been well established that most athletes obtain adequate amounts of protein through their diets alone. However, these studies demonstrate that timing of protein ingestion is of greater importance then quantity.  Figure2 is a table by Ivy 2004, which shows the recommendation on protein shakes for pre, during, and post training. 

Figure 3

Protein Sources
There is a wide variety of protein sources which vary greatly in amino acid profile, digestibility, and nutritional value. Protein is only considered “complete” when it contains all nine of the essential amino acids. Tissue growth and repair can only take place when all the amino acids are present. Sources of complete proteins include animal protein such as eggs, meat, poultry, fish, and dairy. Further complete proteins are almost nonexistent in non animal products. Some examples are hemp, soy, chia, and sacha inichi. Proteins that lack some of the essential amino acids are called “incomplete,” if not combined with complementary foods, growth will not occur, and instead malnutrition is likely to occur. Sources of incomplete proteins far exceed complete proteins, such as, plant proteins. Several examples are corn, lentils, beans, fruits, and nuts. 

Figure 4

Protein type
The type of protein we consume has a significant effect on promoting improvements in strength and body composition. A great deal of studies have demonstrated that animal proteins are superior to vegetarian and that milk is greater than hydrolyzed soy proteins (Campbell, 1999; & Phillips, 2005). Further research has demonstrated that consuming amino acids and proteins rich in non essential amino acids has no added benefit; this was reviewed in Tipton’s 2004 study.

Is casein or whey a better choice for post workout supplement? Both forms of protein are fantastic in themselves. However, it depends on the time of ingestion in relation to exercise which will decide what is better suited (Philips, 2010). When looking at the two hours post training ,whey is anabolic, fast digestibility, and increases protein synthesis (Philips, 2010; Boirie, 1997). As noted before, the window in which protein is used most effectively is within 45 minutes post training. In order to utilize this time as best as possible, one needs the protein to digest as quickly as possible. Therefore, whey protein is superior within proximity to training (Philips, 2010). Casein is superior before bed, due to its slow digestibility and ability to inhibit protein breakdown (Philips, 2010; Boirie, 1997; Dangin, 2001; Tang, 2009). This provides the body with a “trickle” of amino acids over a long period of time (Philips, 2010; Boirie, 1997; Dangin, 2001; Tang, 2009).  In the only head to head studies of casein vs whey, casein supplementation resulted in greater gains in strength, muscle mass, and fat loss (Antonio, 2008; & Demling, 2000). Both whey and casein have benefits and provide enough reason for both to be used.

Protein has been researched in incredible depth over the last 150 years. There is still a great deal of debate amongst researchers and information missing. However, one can conclude that protein is essential for health and performance. Protein is essential in increasing muscle mass and strength. With the proper timing of protein ingestion one can have dramatic improvements in strength and muscle hypertrophy. When deciding on what kind of protein to consume, there is clear evidence that animal protein is superior to vegetarian protein. Finally, by taking advantage of the unique benefits of whey and casein one can significantly improve athletic performance.

  • Abe T, DeHoyos DV, Pollock ML, Garzarella L. Time course for strength and muscle thickness changes following upper and lower body resistance training in men and women. Eur J Appl Physiol 81: 174–180, 2000.
  • American College of Sports Medicine: American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Med Sci Sports Exerc, 41:687-708, 2009
  • Anderson LL, Tufekovic G, Zebis MK, et al. The effect of resistance training combined with timed ingestion of protein on muscle size and muscle strength. Metabolism 54(2) 151-156, 2005.
  • Antonio, Jose. Essentials of sports nutrition and supplements. Totowa, N.J: Humana Press, 2008. Print.
  • Bamman MM, Hill VJ, Adams GR, Haddad F, Wetzstein CJ, Gower BA, Ahmed A, Hunter GR. Gender differences in resistance-training-induced myofiber hypertrophy among older adults. J Gerontol A Biol Sci Med Sci 58: 108–116, 2003.
  • Biolo G, Declan Fleming RY, Wolfe RR. Physiologic hyperinsulinemia stimulates protein synthesis and enhances transport of selected amino acids in human skeletal muscle. J Clin Invest 1995; 95:811–819. 
  • Biolo G, Maggi SP, Williams BD, Tipton KD, Wolfe RR. Increased rates of muscle protein turnover and amino acid transport after resistance exercise in humans. Am J Physiol Endocrinol Metab 268: E514–E520, 1995.
  • Biolo G, Tipton KD, Klein S, Wolfe RR. An abundant supply of amino acids enhances the metabolic effect of exercise on muscle protein.Am J Physiol Endocrinol Metab 273: E122–E129, 1997.
  • Biolo G, Williams BD, Fleming RY, Wolfe RR. Insulin action on muscle protein kinetics and amino acid transport during recovery after resistance exercise. Diabetes 48: 949–957, 1999.
  • Blomstrand E, Eliasson J, Karlsson HK, Kohnke R. Branched-chain amino acids activate key enzymes in protein synthesis after physical exercise. J Nutr 136: 269S–273S, 2006.
  • Bodine SC. mTOR signaling and the molecular adaptation to resistance exercise. Med Sci Sports Exerc 38: 1950–1957, 2006.
  • Boirie Y, Dangin M, Gachon P, Vasson MP, Maubois JL, Beaufrere B. Slow and fast dietary proteins differently modulate postprandial protein accretion. Proc Natl Acad Sci USA 94: 14930–14935, 1997.
  • Bolster DR, Jefferson LS, Kimball SR. Regulation of protein synthesis associated with skeletal muscle hypertrophy by insulin-, amino acid- and exercise-induced signalling. Proc Nutr Soc 63: 351–356, 2004.
  • Bolster DR, Vary TC, Kimball SR, Jefferson LS. Leucine regulates translation initiation in rat skeletal muscle via enhanced eIF4G phosphorylation. J Nutr 134: 1704–1710, 2004.
  • Borsheim E, Aarsland A, Wolfe RR. Effect of an amino acid, protein, and carbohydrate mixture on net muscle protein balance after resistance exercise. Int J Sport Nutr Exerc Metab 14: 255–271, 2004.
  • Borsheim E, Cree MG, Tipton KD, Elliott TA, Aarsland A, Wolfe RR. Effect of carbohydrate intake on net muscle protein synthesis during recovery from resistance exercise. J Appl Physiol 96: 674–678, 2004.
  • Borsheim E, Tipton KD, Wolf SE, Wolfe RR. Essential amino acids and muscle protein recovery from resistance exercise. Am J Physiol Endocrinol Metab 283: E648–E657, 2002.
  • Bos C, Metges CC, Gaudichon C, Petzke KJ, Pueyo ME, Morens C, Everwand J, Benamouzig R, Tome D. Postprandial kinetics of dietary amino acids are the main determinant of their metabolism after soy or milk protein ingestion in humans. J Nutr 133: 1308–1315, 2003.
  • Brose A, Parise G, Tarnopolsky MA. Creatine supplementation enhances isometric strength and body composition improvements following strength exercise training in older adults. J Gerontol A Biol Sci Med Sci 58: 11–19, 2003.
  • Byfield MP, Murray JT, Backer JM. hVps34 is a nutrient-regulated lipid kinase required for activation of p70 S6 kinase. J Biol Chem 280:33076–33082, 2005.
  • Calbet JA, Holst JJ. Gastric emptying, gastric secretion and enterogastrone response after administration of milk proteins or their peptide hydrolysates in humans. Eur J Nutr 43: 127–139, 2004.
  • Candow DG, Chilibeck PD, Facci M, Abeysekara S, Zello GA. Protein supplementation before and after resistance training in older men. Eur J Appl Physiol 97: 548–556, 2006.
  • Carraro F, Hartl WH, Stuart CA, Layman DK, Jahoor F, Wolfe RR. Whole body and plasma protein synthesis in exercise and recovery in human subjects. Am J Physiol Endocrinol Metab 258: E821–E831, 1990.
  • Carraro F, Stuart CA, Hartl WH, Rosenblatt J, Wolfe RR. Effect of exercise and recovery on muscle protein synthesis in human subjects. Am J Physiol Endocrinol Metab 259: E470–E476, 1990.
  • Cathcart EP. Influence of muscule work on protein metabolism. Physiol Rev 5:225-243, 1925.
  • Chesley A, MacDougall JD, Tarnopolsky MA, Atkinson SA, Smith K. Changes in human muscle protein synthesis after resistance exercise. J Appl Physiol 73: 1383–1388, 1992.
  • Chow LS, Albright RC, Bigelow ML, et al. Mechanism of insulin's anabolic effect on muscle: measurements of muscle protein synthesis and breakdown using aminoacyl-tRNA and other surrogate measures. AJP Endocrinol Metab 2006; 291:E729–E736. 
  • Coffey VG, Reeder DW, Lancaster GI, Yeo WK, Febbraio MA, Yaspelkis BB 3rd, Hawley JA. Effect of high-frequency resistance exercise on adaptive responses in skeletal muscle. Med Sci Sports Exerc 39: 2135–2144, 2007.
  • Coffey VG, Zhong Z, Shield A, Canny BJ, Chibalin AV, Zierath JR, Hawley JA. Early signaling responses to divergent exercise stimuli in skeletal muscle from well-trained humans. FASEB J 20: 190–192, 2006.
  • Cuthbertson D, Smith K, Babraj J, Leese G, Waddell T, Atherton P, Wackerhage H, Taylor PM, Rennie MJ. Anabolic signaling deficits underlie amino acid resistance of wasting, aging muscle. FASEB J 19: 422–424, 2005.
  • Dangin M, Boirie Y, Garcia-Rodenas C, Gachon P, Fauquant J, Callier P, Ballevre O, Beaufrere B. The digestion rate of protein is an independent regulating factor of postprandial protein retention. Am J Physiol Endocrinol Metab 280: E340–E348, 2001.
  • Dangin M, Guillet C, Garcia-Rodenas C, Gachon P, Bouteloup-Demange C, Reiffers-Magnani K, Fauquant J, Ballevre O, Beaufrere B. The rate of protein digestion affects protein gain differently during aging in humans. J Physiol 549: 635–644, 2003.
  • Dreyer HC, Drummond MJ, Pennings B, Fujita S, Glynn EL, Chinkes DL, Dhanani S, Volpi E, Rasmussen BB. Leucine-enriched essential amino acid and carbohydrate ingestion following resistance exercise enhances mTOR signaling and protein synthesis in human muscle.Am J Physiol Endocrinol Metab 294: E392–E400, 2008.
  • Dreyer HC, Fujita S, Cadenas JG, Chinkes DL, Volpi E, Rasmussen BB. Resistance exercise increases AMPK activity and reduces 4E-BP1 phosphorylation and protein synthesis in human skeletal muscle. J Physiol 576: 613–624, 2006.
  • Drummond MJ, Miyazaki M, Dreyer HC, Pennings B, Dhanani S, Volpi E, Esser KA, Rasmussen BB. Expression of growth-related genes in young and old human skeletal muscle following an acute stimulation of protein synthesis. J Appl Physiol (September 11 2008).doi:.
  • Drummond MJ, Rasmussen BB. Leucine-enriched nutrients and the regulation of mammalian target of rapamycin signalling and human skeletal muscle protein synthesis. Curr Opin Clin Nutr Met Care 11: 222–226, 2008.
  • Eliasson J, Elfegoun T, Nilsson J, Kohnke R, Ekblom B, Blomstrand E. Maximal lengthening contractions increase p70 S6 kinase phosphorylation in human skeletal muscle in the absence of Nutral supply. Am J Physiol Endocrinol Metab 291: E1197–E1205, 2006.
  • Engelen MP, Rutten EP, De Castro CL, Wouters EF, Schols AM, Deutz NE. Supplementation of soy protein with branched-chain amino acids alters protein metabolism in healthy elderly and even more in patients with chronic obstructive pulmonary disease. Am J Clin Nutr85: 431–439, 2007.
  • Esmarck B, Andersen JL, Olsen S, Richter EA, Mizuno M, Kjaer M. Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans. J Physiol 535: 301–311, 2001.
  • FAO/WHO/UNU. Protein and Amino Acid Requirements in Human Nutrition. WHO Technical Report Series. Geneva, Switzerland: World Health Organization, 2002.
  • Fluck M, Carson JA, Gordon SE, Ziemiecki A, Booth FW. Focal adhesion proteins FAK and paxillin increase in hypertrophied skeletal muscle. Am J Physiol Cell Physiol 277: C152–C162, 1999.
  • Fluck M, Ziemiecki A, Billeter R, Muntener M. Fibre-type specific concentration of focal adhesion kinase at the sarcolemma: influence of fibre innervation and regeneration. J Exp Biol 205: 2337–2348, 2002.
  • Fouillet H, Mariotti F, Gaudichon C, Bos C, Tome D. Peripheral and splanchnic metabolism of dietary nitrogen are differently affected by the protein source in humans as assessed by compartmental modeling. J Nutr 132: 125–133, 2002.
  • Fry AC. The role of resistance exercise intensity on muscle fibre adaptations. Sports Med 2004; 34:663–679. 
  • Fujita S, Abe T, Drummond MJ, Cadenas JG, Dreyer HC, Sato Y, Volpi E, Rasmussen BB. Blood flow restriction during low-intensity resistance exercise increases S6K1 phosphorylation and muscle protein synthesis. J Appl Physiol 103: 903–910, 2007.
  • Fujita S, Dreyer HC, Drummond MJ, Glynn EL, Cadenas JG, Yoshizawa F, Volpi E, Rasmussen BB. Nutrient signalling in the regulation of human muscle protein synthesis. J Physiol 582: 813–823, 2007.
  • Fujita S, Rasmussen BB, Cadenas JG, et al. Effect of insulin on human skeletal muscle protein synthesis is modulated by insulin-induced changes in muscle blood flow and amino acid availability. AJP Endocrinol Metab 2006; 291:E745–E754.
  • Fujita S, Rasmussen BB, Bell JA, Cadenas JG, Volpi E. Basal muscle intracellular amino acid kinetics in women and men. Am J Physiol Endocrinol Metab 292: E77–E83, 2007.
  • Fuller MF, Garlick PJ. Human amino acid requirements: can the controversy be resolved? Ann Rev Nutr 14:217-241, 1994.
  • Funai K, Parkington JD, Carambula S, Fielding RA. Age-associated decrease in contraction-induced activation of downstream targets of Akt/mTor signaling in skeletal muscle. Am J Physiol Regul Integr Comp Physiol 290: R1080–R1086, 2006.
  • Glover EI, Oates BR, Tang JE, Moore DR, Tarnopolsky MA, Phillips SM. Resistance exercise decreases eIF2Bε phosphorylation and potentiates the feeding-induced stimulation of p70S6K1 and rpS6 in young men. Am J Physiol Regul Integr Comp Physiol 295: R604–R610, 2008.
  • Goldspink G, Howells KF. Work-induced hypertrophy in exercised normal muscles of different ages and the reversibility of hypertrophy after cessation of exercise. J Physiol 239: 179–193, 1974.
  • Gordon SE, Fluck M, Booth FW. Selected Contribution: Skeletal muscle focal adhesion kinase, paxillin, and serum response factor are loading dependent. J Appl Physiol 90: 1174–1183, 2001.
  • Greenhaff PL, Karagounis L, Peirce N, Simpson EJ, Hazell M, Layfield R, Wackerhage H, Smith K, Atherton P, Selby A, Rennie MJ. Disassociation between the effects of amino acids and insulin on signaling, ubiquitin-ligases, and protein turnover in human muscle. Am J Physiol Endocrinol Metab 295: E595–E604, 2008.
  • Hansen M, Koskinen SO, Petersen SG, Doessing S, Frystyk J, Flyvbjerg A, Westh E, Magnusson SP, Kjaer M, Langberg H.Ethinyl oestradiol administration in women suppresses synthesis of collagen in tendon in response to exercise. J Physiol 586: 3005–3016, 2008.
  • Hartman JW, Tang JE, Wilkinson SB, Tarnopolsky MA, Lawrence RL, Fullerton AV, Phillips SM. Consumption of fat-free fluid milk after resistance exercise promotes greater lean mass accretion than does consumption of soy or carbohydrate in young, novice, male weightlifters.Am J Clin Nutr 86: 373–381, 2007.
  • Holm L, Reitelseder S, Pedersen TG, Doessing S, Petersen SG, Flyvbjerg A, Andersen JL, Aagaard P, Kjaer M. Changes in muscle size and MHC composition in response to resistance exercise with heavy and light loading intensity. J Appl Physiol 105: 1454–1461, 2008.
  • Hubal MJ, Gordish-Dressman H, Thompson PD, Price TB, Hoffman EP, Angelopoulos TJ, Gordon PM, Moyna NM, Pescatello LS, Visich PS, Zoeller RF, Seip RL, Clarkson PM. Variability in muscle size and strength gain after unilateral resistance training. Med Sci Sports Exerc 37: 964–972, 2005.
  • Hulmi J, Lockwood C, & Stout J. Review Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein. Nutrition & Metabolism 7:51, 2010.
  • Ivy J, Goforth HW,Damon BM, McCauley Tr, Parsons P. Early post exercise in muscle glycogen recovery is enhanced with carnohydrate-protein supplement. J Appl Physiol 93(4):1337:1344, 2002.
  • Ivy J, & Portman R. Nutrient timing: the future of sports nutrition. Laguna Beach, CA: Basic Health Publications, 2004. Print.
  • Jentjens RL, Van Loon LJ, Mann CH, Wagenmakers AJ, Jeukendrup AE. Addition of protein and amino acids to carbohydrates does not enhance post exercice mu8scle glycogen synthesis. J Appl Physil 91(2):839-846, 2001.
  • Karlsson HK, Nilsson PA, Nilsson J, Chibalin AV, Zierath JR, Blomstrand E. Branched-chain amino acids increase p70S6k phosphorylation in human skeletal muscle after resistance exercise. Am J Physiol Endocrinol Metab 287: E1–E7, 2004.
  • Katsanos CS, Kobayashi H, Sheffield-Moore M, Aarsland A, Wolfe RR. A high proportion of leucine is required for optimal stimulation of the rate of muscle protein synthesis by essential amino acids in the elderly. Am J Physiol Endocrinol Metab 291: E381–E387,2006.
  • Kim PL, Staron RS, Phillips SM. Fasted-state skeletal muscle protein synthesis after resistance exercise is altered with training. J Physiol568: 283–290, 2005.
  • Kimball SR, Jefferson LS. Signaling pathways and molecular mechanisms through which branched-chain amino acids mediate translational control of protein synthesis. J Nutr 136: 227S–231S, 2006.
  • Koopman R, Pennings B, Zorenc AH, van Loon LJ. Protein ingestion further augments S6K1 phosphorylation in skeletal muscle following resistance type exercise in males. J Nutr 137: 1880–1886, 2007.
  • Koopman R, Saris WH, Wagenmakers AJ, van Loon LJ. Nutral interventions to promote post-exercise muscle protein synthesis. Sports Med (Auckland, NZ) 37: 895–906, 2007.
  • Koopman R, Verdijk L, Manders RJ, Gijsen AP, Gorselink M, Pijpers E, Wagenmakers AJ, van Loon LJ. Co-ingestion of protein and leucine stimulates muscle protein synthesis rates to the same extent in young and elderly lean men. Am J Clin Nutr 84: 623–632, 2006.
  • Koopman R, Verdijk LB, Beelen M, Gorselink M, Kruseman AN, Wagenmakers AJ, Kuipers H, van Loon LJ. Co-ingestion of leucine with protein does not further augment postexercise muscle protein synthesis rates in elderly men. Br J Nutr 94: 1–10, 2008.
  • Koopman R, Verdijk LB, Beelen M, Gorselink M, Kruseman AN, Wagenmakers AJ, Kuipers H, van Loon LJ. Co-ingestion of leucine with protein does not further augment post-exercise muscle protein synthesis rates in elderly men. Br J Nutr 99: 571–580, 2008.
  • Koopman R, Zorenc AH, Gransier RJ, Cameron-Smith D, van Loon LJ. Increase in S6K1 phosphorylation in human skeletal muscle following resistance exercise occurs mainly in type II muscle fibers. Am J Physiol Endocrinol Metab 290: E1245–E1252, 2006.
  • Kosek DJ, Kim JS, Petrella JK, Cross JM, Bamman MM. Efficacy of 3 days/wk resistance training on myofiber hypertrophy and myogenic mechanisms in young vs. older adults. J Appl Physiol 101: 531–544, 2006.
  • Kraemer WJ, Adams K, Cafarelli E, et al. American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Med Sci Sports Exerc 2002; 34:364–380. 
  • Kraemer WJ, Ratamess NA. Fundamentals of resistance training: progression and exercise prescription. Med Sci Sports Exerc 36: 674–688, 2004.
  • Kraemer WJ, Staron RS, Hagerman FC, et al. The effects of short-term resistance training on endocrine function in men and women. Eur J Appl Physiol Occup Physiol 1998; 78:69–76. 
  • Kreider, R.B. dietary supplements and the promotion of muscle growth with resistance exercise. sports med. 27:97–110, 1999.
  • Kumar V, Selby A, Rankin D, Patel R, Atherton P, Hildebrandt W, Williams J, Smith K, Seynnes O, Hiscock N, Rennie MJ. Age-related differences in dose response of muscle protein synthesis to resistance exercise in young and old men. J Physiol 587: 211–217, 2008.
  • Lambert Cp, Frank LL, Evans WJ. Macronutrient considerations for sport of bodybuilding. Sports Med 34(5):317-327, 2004.
  • Lamont LS, McCullough AJ, Kalhan SC. Gender differences in leucine, but not lysine, kinetics. J Appl Physiol 91: 357–362, 2001.
  • Lamont LS, McCullough AJ, Kalhan SC. Gender differences in the regulation of amino acid metabolism. J Appl Physiol 95: 1259–1265,2003.
  • Lecker SH, Solomon V, Mitch WE, Goldberg AL. Muscle protein breakdown and the critical role of the ubiquitin-proteasome pathway in normal and disease states. J Nutr 129: 227S–237S, 1999.
  • Lemon, P.W.R. Effect of exercise on protein requirements. J Sports Sci 9:53-70, 1991.
  • Lemon, P.W.R. Dietary protein requirements in athletes. Nutr Biochem 8: 52-60, 1997.
  • Lemon, P.W.R. Beyond the zone: protein needs of active individuals. J Am coll Nutr 19(5):513s-521s, 2000
  • Lemon, P.W.R, & Proctor, D.N. Protein intake and athletic performance. Sports Med 12(5): 313-325, 1991.
  • Lemon, P.W.R., M.A. Tarnopolsky, J. Duncan Macdougall, and S.A. Atkinson. Protein requirements and muscle mass/strength changes during intensive training in novice bodybuilders. J. Appl. Physiol. 73:767–775, 1992.
  • Liu Z, Jahn LA, Long W, Fryburg DA, Wei L, Barrett EJ. Branched chain amino acids activate messenger ribonucleic acid translation regulatory proteins in human skeletal muscle, and glucocorticoids blunt this action. J Clin Endocrinol Metab 86: 2136–2143, 2001.
  • Liu Z, Jahn LA, Wei L, Long W, Barrett EJ. Amino acids stimulate translation initiation and protein synthesis through an Akt-independent pathway in human skeletal muscle. J Clin Endocrinol Metab 87: 5553–5558, 2002.
  • Ma K, Mallidis C, Bhasin S, Mahabadi V, Artaza J, Gonzalez-Cadavid N, Arias J, Salehian B. Glucocorticoid-induced skeletal muscle atrophy is associated with upregulation of myostatin gene expression. Am J Physiol Endocrinol Metab 285: E363–E371, 2003.
  • Maclean, D.A., and T.E. Graham. Branched-chain amino acid supplementation augments plasma ammonia responses during exercise in humans. J. Appl. Physiol. 74:2711–2717, 1993.
  • MacDougall JD, Gibala MJ, Tarnopolsky MA, MacDonald JR, Interisano SA, Yarasheski KE. The time course for elevated muscle protein synthesis following heavy resistance exercise. Can J Appl Physiol 20: 480–486, 1995.
  • MacDougall JD, Tarnopolsky MA, Chesley A, Atkinson SA. Changes in muscle protein synthesis following heavy resistance exercise in humans: a pilot study. Acta Physiol Scand 146: 403–404, 1992.
  • Mascher H, Andersson H, Nilsson PA, Ekblom B, Blomstrand E. Changes in signaling pathways regulating protein synthesis in human muscle in the recovery period after endurance exercise. Acta Physiol (Oxford, England) 191: 67–75, 2007.
  • Miller BF, Hansen M, Olesen JL, Flyvbjerg A, Schwarz P, Babraj JA, Smith K, Rennie MJ, Kjaer M. No effect of menstrual cycle on myofibrillar and connective tissue protein synthesis in contracting skeletal muscle. Am J Physiol Endocrinol Metab 290: E163–E168, 2006.
  • Miller BF, Hansen M, Olesen JL, Schwarz P, Babraj JA, Smith K, Rennie MJ, Kjaer M. Tendon collagen synthesis at rest and after exercise in women. J Appl Physiol 102: 541–546, 2007.
  • Miller BF, Olesen JL, Hansen M, Dossing S, Crameri RM, Welling RJ, Langberg H, Flyvbjerg A, Kjaer M, Babraj JA, Smith K, Rennie MJ. Coordinated collagen and muscle protein synthesis in human patella tendon and quadriceps muscle after exercise. J Physiol 567:1021–1033, 2005.
  • Miller SL, Tipton KD, Chinkes DL, Wolf SE, Wolfe RR. Independent and combined effects of amino acids and glucose after resistance exercise. Med Sci Sports Exerc 35: 449–455, 2003.
  • Mittendorfer B, Andersen JL, Plomgaard P, Saltin B, Babraj JA, Smith K, Rennie MJ. Protein synthesis rates in human muscles: neither anatomical location nor fibre-type composition are major determinants. J Physiol 563: 203–211, 2005.
  • Moore DR, Phillips SM, Babraj JA, Smith K, Rennie MJ. Myofibrillar and collagen protein synthesis in human skeletal muscle in young men after maximal shortening and lengthening contractions. Am J Physiol Endocrinol Metab 288: E1153–E1159, 2005.
  • Moore DR, Robinson MJ, Fry JL, Tang JE, Glover EI, Wilkinson SB, Prior T, Tarnopolsky MA, Phillips SM. Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am J Clin Nutr 89: 161–168, 2009.
  • Moritani T, Sherman WM, Shibata M, Matsumoto T, Shinohara M. Oxygen availability and motor unit activity in humans. Eur J Appl Physiol 64: 552–556, 1992.
  • Nair KS, Halliday D, Griggs RC. Leucine incorporation into mixed skeletal muscle protein in humans. Am J Physiol Endocrinol Metab254: E208–E213, 1988.
  • Nakshabendi IM, McKee R, Downie S, Russell RI, Rennie MJ. Rates of small intestinal mucosal protein synthesis in human jejunum and ileum. Am J Physiol Endocrinol Metab 277: E1028–E1031, 1999.
  • Nakshabendi IM, Obeidat W, Russell RI, Downie S, Smith K, Rennie MJ. Gut mucosal protein synthesis measured using intravenous and intragastric delivery of stable tracer amino acids. Am J Physiol Endocrinol Metab 269: E996–E999, 1995.
  • Nobukuni T, Joaquin M, Roccio M, Dann SG, Kim SY, Gulati P, Byfield MP, Backer JM, Natt F, Bos JL, Zwartkruis FJ, Thomas G. Amino acids mediate mTOR/raptor signaling through activation of class 3 phosphatidylinositol 3OH-kinase. Proceedings of the Natl Acad Sci USA 102: 14238–14243, 2005.
  • Paddon-Jones D, Sheffield-Moore M, Zhang XJ, Volpi E, Wolf SE, Aarsland A, Ferrando AA, Wolfe RR. Amino acid ingestion improves muscle protein synthesis in the young and elderly. Am J Physiol Endocrinol Metab 286: E321–E328, 2004.
  • Parkington JD, LeBrasseur NK, Siebert AP, Fielding RA. Contraction-mediated mTOR, p70S6k, and ERK1/2 phosphorylation in aged skeletal muscle. J Appl Physiol 97: 243–248, 2004.
  • Phillips SM. Dietary protein for athletes: from requirements to metabolic advantage. Appl Physiol Nutr Metab 31: 647–654, 2006.
  • Phillips SM. Insulin and muscle protein turnover in humans: stimulatory, permissive, inhibitory, or all of the above? Am J Physiol Endocrinol Metab 295: E731, 2008.
  • Phillips SM, Atkinson SA, Tarnopolsky MA, MacDougall JD. Gender differences in leucine kinetics and nitrogen balance in endurance athletes. J Appl Physiol 75: 2134–2141, 1993.
  • Phillips SM, Hartman JW, Wilkinson SB. Dietary protein to support anabolism with resistance exercise in young men. J Am Coll Nutr 24:134S–139S, 2005.
  • Phillips SM, Parise G, Roy BD, Tipton KD, Wolfe RR, Tarnopolsky MA. Resistance training-induced adaptations in skeletal muscle protein turnover in the fed state. Can J Physiol Pharmacol 80: 1045–1053, 2002.
  • Phillips SM, Tipton KD, Aarsland A, Wolf SE, Wolfe RR. Mixed muscle protein synthesis and breakdown after resistance exercise in humans. Am J Physiol Endocrinol Metab 273: E99–E107, 1997.
  • Phillips SM, Tipton KD, Ferrando AA, Wolfe RR. Resistance training reduces the acute exercise-induced increase in muscle protein turnover. Am J Physiol Endocrinol Metab 276: E118–E124, 1999.
  • Pikosky MA, Gaine PC, Martin WF, Grabarz KC, Ferrando AA, Wolfe RR, Rodriguez NR. Aerobic exercise training increases skeletal muscle protein turnover in healthy adults at rest. J Nutr 136: 379–383, 2006.
  • Pilegaard H, Saltin B, Neufer PD. Effect of short-term fasting and refeeding on transcriptional regulation of metabolic genes in human skeletal muscle. Diabetes 52: 657–662, 2003.
  • Pitkänen HT, Nykanen T, Knuutinen J, Lahti K, Keinanen O, Alen M, Komi PV, Mero AA: Free amino acid pool and muscle protein balance after resistance exercise. Med Sci Sports Exerc 2003, 35:784-792.
  • Powers, Scott K., and Edward T. Howley. Exercise physiology: theory and application to fitness and performance. 6th ed. Boston: McGraw-Hill, 2007. Print.
  •  Proud CG. Signalling to translation: how signal transduction pathways control the protein synthetic machinery. Biochem J 403: 217–234,2007.
  • Rankin JW. Role of protein in exercise. Clin Sports Med 18(3):499-511, 1999.
  • Rasmussen BB, Phillips SM. Contractile and nutral regulation of human muscle growth. Exerc Sport Sci Rev 31: 127–131, 2003.
  • Rasmussen BB, Tipton KD, Miller SL, Wolf SE, Wolfe RR. An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise. J Appl Physiol 88: 386–392, 2000.
  • Rennie MJ. Control of muscle protein synthesis as a result of contractile activity and amino acid availability: implications for protein requirements. Int J Sport Nutr Exerc Metab 11, Suppl: S170–S176, 2001.
  • Rennie Mj, & Tipton KD. Protein and amino acid metabolism during and after exercise and the effects of nutrition. Annu Rev Nuty 20:457-483, 2000)
  • Rennie MJ, Wackerhage H, Spangenburg EE, Booth FW. Control of the size of the human muscle mass. Annu Rev Physiol 66: 799–828,2004.
  • Rieu I, Balage M, Sornet C, Giraudet C, Pujos E, Grizard J, Mosoni L, Dardevet D. Leucine supplementation improves muscle protein synthesis in elderly men independently of hyperaminoacidaemia. J Physiol 575: 305–315, 2006.
  • Roberts RG, Redfern CP, Goodship TH. Effect of insulin upon protein degradation in cultured human myocytes. Eur J Clinical Invest 33:861–867, 2003.
  • Roepstorff C, Donsmark M, Thiele M, Vistisen B, Stewart G, Vissing K, Schjerling P, Hardie DG, Galbo H, Kiens B. Sex differences in hormone-sensitive lipase expression, activity, and phosphorylation in skeletal muscle at rest and during exercise. Am J Physiol Endocrinol Metab 291: E1106–E1114, 2006.
  • Roy BD, Luttmer K, Bosman MJ, Tarnopolsky MA. The influence of post-exercise macronutrient intake on energy balance and protein metabolism in active females participating in endurance training. Metabolism 54(2):151-156, 2005.
  • Schaafsma G. The protein digestibility-corrected amino acid score. J Nutr 130: 1865S-1867S, 2000.
  • Schaafsma G. The protein digestibility-corrected amino acid score (PDAAS)-a concept for describing protein quality in foods and food ingredients: a critical review. J AOAC Int 88(3): 998-994, 2005
  • Sheffield-Moore M, Yeckel CW, Volpi E, Wolf SE, Morio B, Chinkes DL, Paddon-Jones D, Wolfe RR. Postexercise protein metabolism in older and younger men following moderate-intensity aerobic exercise. Am J Physiol Endocrinol Metab 287: E513–E522, 2004.
  • Short KR, Vittone JL, Bigelow ML, Proctor DN, Nair KS. Age and aerobic exercise training effects on whole body and muscle protein metabolism. Am J Physiol Endocrinol Metab 286: E92–E101, 2004.
  • Skilton MR, Lai NT, Griffiths KA, Molyneaux LM, Yue DK, Sullivan DR, Celermajer DS. Meal-related increases in vascular reactivity are impaired in older and diabetic adults: insights into roles of aging and insulin in vascular flow. Am J Physiol Heart Circ Physiol 288: H1404–H1410, 2005.
  • Smith G, Villareal DT, Sinacore D, Shah K, Mittendorfer B. The anabolic response to exercise training is greater in older men than older women. In: 2008 APS Conference. The Integrative Biology of Exercise-V. September 24–27, 2008, Hilton Head, South Carolina. Section: Gender differences. Abstract no. 17.2, p. 42.
  • Smith GI, Atherton P, Villareal DT, Frimel TN, Rankin D, Rennie MJ, Mittendorfer B. Differences in muscle protein synthesis and anabolic signaling in the postabsorptive state and in response to food in 65–80 year old men and women. PLoS ONE 3: e1875, 2008.
  • Smith K, Reynolds N, Downie S, Patel A, Rennie MJ. Effects of flooding amino acids on incorporation of labeled amino acids into human muscle protein. Am J Physiol Endocrinol Metab 275: E73–E78, 1998.
  • Staron RS, Malicky ES, Leonardi MJ, Falkel JE, Hagerman FC, Dudley GA. Muscle hypertrophy and fast fiber type conversions in heavy resistance-trained women. Eur J Appl Physiol 60: 71–79, 1990.
  • Symons TB, Schutzler SE, Cocke TL, Chinkes DL, Wolfe RR, Paddon-Jones D Aging does not impair the anabolic response to a protein-rich meal. Am J Clin Nutr 86: 451–456, 2007.
  • Takarada Y, Sato Y, Ishii N. Effects of resistance exercise combined with vascular occlusion on muscle function in athletes. Eur J Appl Physiol 86: 308–314, 2002.
  • Takarada Y, Takazawa H, Sato Y, Takebayashi S, Tanaka Y, Ishii N. Effects of resistance exercise combined with moderate vascular occlusion on muscular function in humans. J Appl Physiol 88: 2097–2106, 2000.
  • Tang JE, Manolakos JJ, Kujbida GW, Lysecki PJ, Moore DR, Phillips SM. Minimal whey protein with carbohydrate stimulates muscle protein synthesis following resistance exercise in trained young men. Appl Physiol Nutr Metab 32: 1132–1138, 2007.
  • Tang JE, Perco JG, Moore DR, Wilkinson SB, Phillips SM. Resistance training alters the response of fed state mixed muscle protein synthesis in young men. Am J Physiol Regul Integr Comp Physiol 294: R172–R178, 2008.
  • Tang JE, & Philips S. Maximizing muscle protein anabolism: the role of protein quality. Curr Opin Clin Nutr Metab Care 12:66–71, 2009
  • Tranopolsky MA. Protein Requirements for endurance athletes. Nutition 20(7-8):662-668, 2004
  • Tarnopolsky MA. Sex differences in exercise metabolism and the role of 17-beta estradiol. Med Sci Sports Exerc 40: 648–654, 2008.
  • Tarnopolsky MA, Atkinson SA, MacDougall JD, Chesley A, Phillips S, Schwarcz HP. Evaluation of protein requirements for trained strength athletes. J Appl Physiol 73: 1986–1995, 1992
  • Tipton KD, Elliott TA, Cree MG, Aarsland AA, Sanford AP, Wolfe RR. Stimulation of net muscle protein synthesis by whey protein ingestion before and after exercise. Am J Physiol Endocrinol Metab 292: E71–E76, 2007.
  • Tipton KD, Elliott TA, Cree MG, Wolf SE, Sanford AP, Wolfe RR. Ingestion of casein and whey proteins result in muscle anabolism after resistance exercise. Med Sci Sports Exerc 36: 2073–2081, 2004.
  • Tipton KD, Ferrando AA, Phillips SM, Doyle D Jr, Wolfe RR. Postexercise net protein synthesis in human muscle from orally administered amino acids. Am J Physiol Endocrinol Metab 276: E628–E634, 1999.
  • Tipton KD, Ferrando AA, Williams BD, Wolfe RR. Muscle protein metabolism in female swimmers after a combination of resistance and endurance exercise. J Appl Physiol 81: 2034–2038, 1996.
  • Tipton KD, Gurkin BE, Matin S, Wolfe RR. Nonessential amino acids are not necessary to stimulate net muscle protein synthesis in healthy volunteers. J Nutr Biochem 10: 89–95, 1999.
  • Tipton KD, Rasmussen BB, Miller SL, Wolf SE, Owens-Stovall SK, Petrini BE, Wolfe RR. Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. Am J Physiol Endocrinol Metab 281: E197–E206, 2001.
  • Tipton KD, Wolfe RR. Protein and amino acids for atheletes. J Sports Sci 22:65-79
  • Tom, Teri. Martial arts nutrition: a precision guide to fueling your fighting edge. Tokyo: Tuttle Pub., 2009. Print.
  • Tortora, Gerard J., and Bryan Derrickson. Principles of anatomy and physiology. 12th ed. Hoboken, NJ: John Wiley & Sons, 2009. Print.
  • Trappe TA, Raue U, Tesch PA. Human soleus muscle protein synthesis following resistance exercise. Acta Physiol Scand 182: 189–196,2004.
  • Ventadour S, Attaix D. Mechanisms of skeletal muscle atrophy. Curr Opin Rheumatol 18: 631–635, 2006.
  • Vincent MA, Clerk LH, Lindner JR, Price WJ, Jahn LA, Leong-Poi H, Barrett EJ. Mixed meal and light exercise each recruit muscle capillaries in healthy humans. Am J Physiol Endocrinol Metab 290: E1191–E1197, 2006.
  • Volpi E, Kobayashi H, Sheffield-Moore M, et al. Essential amino acids are primarily responsible for the amino acid stimulation of muscle protein anabolism in healthy elderly adults. Am J Clin Nutr 2003; 78:250–258. 
  • Volpi E, Ferrando AA, Yeckel CW, et al. Exogenous amino acids stimulate net muscle protein synthesis in the elderly. J Clin Invest 1998; 101:2000–2007. 
  • Volpi E, Mittendorfer B, Rasmussen BB, Wolfe RR. The response of muscle protein anabolism to combined hyperaminoacidemia and glucose-induced hyperinsulinemia is impaired in the elderly. J Clin Endocrinol Metab 85: 4481–4490, 2000.
  • Von Leibig J. Animal chemistry or organic chemistry in its application to physiology. London: Taylor &Walton, 1842.
  • Wackerhage H, Ratkevicius A. Signal transduction pathways that regulate muscle growth. Essays biochem 44: 99–108, 2008.
  • Wang N, Hikida RS, Staron RS, Simoneau JA. Muscle fiber types of women after resistance training–quantitative ultrastructure and enzyme activity. Pflügers Arch 424: 494–502, 1993.
  • Welle S, Bhatt K, Thornton CA. Stimulation of myofibrillar synthesis by exercise is mediated by more efficient translation of mRNA. J Appl Physiol 86: 1220–1225, 1999.
  • Westh E, Kongsgaard M, Bojsen-Moller J, Aagaard P, Hansen M, Kjaer M, Magnusson SP. Effect of habitual exercise on the structural and mechanical properties of human tendon, in vivo, in men and women. Scand J Med Sci Sports 18: 23–30, 2008.
  • Wilkinson SB, Phillips SM, Atherton PJ, Patel R, Yarasheski KE, Tarnopolsky MA, Rennie MJ. Differential effects of resistance and endurance exercise in the fed state on signalling molecule phosphorylation and protein synthesis in human muscle. J Physiol 586: 3701–3717,2008.
  • Wilkinson SB, Tarnopolsky MA, MacDonald MJ, Macdonald JR, Armstrong D, Phillips SM. Consumption of fluid skim milk promotes greater muscle protein accretion following resistance exercise than an isonitrogenous and isoenergetic soy protein beverage. Am J Clin Nutr 85: 1031–1040, 2007.
  • Williamson D, Gallagher P, Harber M, Hollon C, Trappe S. Mitogen-activated protein kinase (MAPK) pathway activation: effects of age and acute exercise on human skeletal muscle. J Physiol 547: 977–987, 2003.
  • Wolfe RR. Regulation of muscle protein by amino acids. J Nutr 2002; 132:3219S–3224S.
  • Wolfe RR, Chinkes D. Isotope Tracers in Metabolic Research. New York: Wiley, 2005.
  • Young VR, Pellett PL. Plant proteins in relation to human protein and amino acid nutrition . Am J Clin Nutr 59(5):1203s-1212s, 1994.
  • Zawadzki KM, Yaspelkis BB, Ivy JL. Carbohydrate-protein complex increases the rate of muscle glycogen storage after exercise. J Appl Physiol 72(5): 1854-1859, 1992.

  • Figure 1: http://www.nutritionexpress.com/article+index/authors /editor /showarticle. aspx?articleid= 743
  • Figure 2: http://www.nutridesk.com.au/post-exercise-metabolic-window.phtml
  • Figure 3: Ivy J, & Portman R. Nutrient timing: the future of sports nutrition. Laguna Beach, CA: Basic Health Publications, 2004. Print.
  • Figure 4: http://tigerfitnessla.com/blog/wp-content/uploads/2009/06/protein-compliments-vegan.jpg


  1. carl can says:

    I am to submit a report on this niche your post has been very very helpfull cash advance

  1. I am glad you enjoyed it and found it helpful