Of all the forms and types and strands of the much loved Protein, whey protein is the King.
Its proposed benefits on muscle development make it hugely popular and recognisable as one of the most common and widespread sports nutrition supplements (32-33). Due to this prevalent use by gym goers and sports people, it has also been the subject of a vast amount of scientific literature.
The purpose of this article is to cut through all of this literature to give you, the average gym goer or athlete, the real facts regarding Whey Protein to help you decide if Whey is the way to go.
What Is Whey Protein?
Whey used to be considered a waste by-product of cheese and curd manufacturing. Approximately 20% of the protein in cows’ milk is whey. During the industrial production of cheese and curd, milk goes through a structured process which includes pasteurisation, inoculation and incubation before Rennet extract is added.
The addition of Rennet extract (a complex of enzymes taken from the stomachs of newborn calves) assists the coagulation of milk and separates it into curds and whey (remember Little Miss Muffet?)
The Difference Between Whey Concentrate & Isolate
The newly separated mixture is then filtered and neutralised with citric acid. Continuous filtration of this liquid whey concentrates its protein percentage down to 80% protein. Further microfiltration can boost protein concentration up to 90% (13)! The liquid whey solution is then warmed and spray dried to become a whey protein powder. This is often described as whey Concentrate and still includes a level of fat and carbohydrates (in the form of lactose).
This form of protein can have between 29-90% total protein but 70% and 80% concentrations are the most commonly seen in sports nutrition supplements (13-14).
There are also variations on whey protein based upon different manufacturing processes which are applied to the whey. These are labelled as Isolate(where water is removed along with all lactose and cholesterol leading to a 95% protein concentration) and Hydrolysate (where the whey is partially pre-digested with enzymes to reduce the size of the peptide molecules and to accelerate absorption and amino acid availability) (47). Whey protein hydrolysate is commonly suggested to be the optimal form of whey protein (67).
The Benefits of Whey Protein
The focus in this piece is predominantly in examining the effect of whey protein on healthy individuals.
This is simply for succinctness as it would be difficult to examine each potentially benefited subgroup in detail. As such we are unable to delve into all the added benefits for specific special populations despite likely benefits.
For example, whey can be consumed alongside vitamin D and exercise to boost fat free mass, strength, functional outcomes and well-being in the elderly to combat aged-related muscle mass decline (63).
It is clear from the scientific literature that the vast majority of the research supports the idea that people who engage in exercise and sport regularly require more protein in their diet or via supplementation than people who are sedentary (13). This is down to the need to consume protein to reach a positive net protein balance.
Benefits | Muscle Protein Synthesis
The amount of muscle gained or lost is a reflection of protein metabolism. Simply put, protein accretion or protein loss is decided upon a careful balance of muscle protein synthesis (MPS) and muscle protein breakdown (54).
Protein and amino acid consumption (through diet or supplementation) will stimulate MPS and a positive net protein balance, whilst fasting will lead to higher rate of breakdown and a negative net protein balance (5). Healthy, active people have a protein turnover rate of 1.5-2% per day (17).
Breakdown of skeletal muscle protein is also caused by exercise; meaning in order to sustain a positive protein balance, an individual would need to consume more protein.
So, this shows that exercising individuals have a need to consume more protein- however does Whey Protein assist in this task?
Several well designed studies have shown that whey protein supplementation specifically, with dosages varying from 20g-40g, is effective in maximising the stimulation of muscle protein synthesis in all individuals respective of age (29,67,73).
This shows that biologically whey protein can induce the stimulation of MPS, but is this effect transferable to us as humans?
One study took data from 9 randomised, controlled trials which included cumulatively 192 participants (52). These authors found that the ingestion of whey protein either alone, or as part of a multi-ingredient stack, was associated with extra gains in both fat-free mass or lean body mass IF combined with resistance training. This was a greater gain than seen with either carbohydrate or a non-whey protein supplement, and was alongside increases in both upper and lower body strength. This study therefore indicates that the biological benefit of stimulating MPS seems to lead to real-world physical changes for the person consuming whey protein.
Another study supported these results (11) and showed a 200% greater increase in lean body mass and strength when whey protein is consumed, compared to carbohydrates. This study interestingly was undertaken on healthy individuals with an average of 5 years of resistance training experience- indicating that benefits are not only for those undertaking a first exposure to weight training (who are more likely to gain greater increases in muscle mass). Other studies have aimed to assess whey protein’s capacity to boost muscle mass and strength gains against other forms of whey protein (e.g. casein or soy).
One such study showed that at doses of 1.5g per kg of bodyweight both whey protein isolate and casein protein showed similar outcomes regarding an equal increase in lean mass and strength (19). However, other authors have shown that when the results of several studies are collated, that whey protein led to significantly greater increases in lean body mass compared to both casein and soy protein sources (56).
Benefits | Whey Protein and Performance
Importantly for athletes and sports people, alongside the physiological changes apparent with whey protein supplementation, there is also likely performance related benefits reported.
The benefits of non-specific protein supplementation on resistance training exercise performance and post exercise adaptations has been outlined in a large meta-analysis study of 22 trials (16).
Based on data from 680 participants, the combined findings showed not only a 0.91kg increase in fat free mass but also a 20.7kg greater increase in 1 rep max single leg press strength! Now as stated this is not specific to whey protein – however as the most fast acting and readily absorbed protein source it goes without saying it is likely whey protein will replicate these benefits.
A study from 2006 aimed to evaluate whether whey and casein protein were equally effective at facilitating strength gains (19). This study followed 13 male bodybuilders for 10 weeks as they supplemented their diet with 1.5g per kg of bodyweight of either whey or casein protein, and underwent a supervised training regime. Their results found a significantly greater increase in 1 rep max strength in the bench press, squat and cable pull down with those given the whey protein supplement.
This was alongside a 5kg greater increase in lean mass and 1.5kg greater loss in fat mass with whey (compared to casein). These findings are further supported by evidence that consumption of 1.5g per kg of bodyweight of whey protein isolate daily is effectively at minimising performance losses during recovery from intensive exercise (18). This was the case with strength performance in the leg press, knee extension and hamstring curl exercises. Certainly resistance training typical to bodybuilding may be an obvious activity which is likely to benefit from whey protein supplementation.
However team sports performance has also been shown to gain advantage from this supplement. Notably national college level basketball players have been shown to improve with 1.4kg increases in lean mass and 4.9kg greater increases in 1 rep max leg press strength.
However this was also alongside development of sport specific running agility performance which was not seen in the carbohydrate control group (72). This would indicate that stand alone performance variables and physical anthropometric changes which change with whey protein consumption, may also lead to improved sport specific performance.
Whey Protein Dosage
Firstly, we need to establish the recommended daily allowance advised to sustain a balance of protein synthesis versus degradation in health adults, to account for differences in protein metabolism and nitrogen losses (via urination and excretion).
This value is 0.8g per kg of bodyweight daily (35), which for an average 80kg man would be:
0.8g x 80kg bodyweight = 64g per day
This value is suggested to cover 97.5% of healthy men and women over the age of 19 years old. However, it is also advised that the cost of exercising in regards to protein metabolism will be greater in those who exercise and require more protein to allow lean tissue development and repair post training (36,68). In fact the predominant nutritional guidelines for protein consumption suggest that for physically active people up to 2g per kg per day is both safe and more effective post training (13).
Such guidelines also suggest that whilst every step should be taken to obtain protein via whole foods in the diet, protein supplementation through sources such as whey, is an effective and efficient way of making sure protein intake is met (13).
For the purposes of clarity we will now outline the proposed dosage recommendations for varied forms of activity and exercise, as each will predispose the participant to different physical stressors which may require a different amount of protein consumption.
Whey Dosage For Endurance Athletes
Generally protein intake should range from 1g/ kg to 1.6g/ kg depending upon the duration and intensity of performance (27,43,49,69).
The advised dosage for 2 bouts of 90 minutes cycling at 46% VO2 max was 1g per kg per day (21).
A dosage of 1.6g per kg per day meets the protein (nitrogen balance) requirements for experienced runners (70).
In an elite running population this requirement is suggested to reduce to 1.49g per kg per day (25).
Whey Dosage For Strength Training
It is likely obvious to most that activities involving strength, such as weight lifting and bodybuilding have a higher protein requirement than endurance activities. This is particularly evident when undertaking the early stages of training or when volume of exercise changes dramatically.
However, the scientific literature does not have a specific dosage which is more commonly quoted for this population. Rather a range of protein consumption levels are usually seen.
1.2-1.8g per kg per day is suggested to stimulate lean muscle mass accretion (1,16,38,42,69-70).
This same dosage (1.2-1.8g) will facilitate adaptations to training if sufficient calories are provided also (57-58,65,71,75-76,80).
Body builders are suggested to consume 1.12g per kg per day specifically (70).
Power sport athletes (such as Olympic weight lifting) are suggested to consume between 1.6-2g per kg per day (2,36,42,44,69).
Doses of 2.3-3.1g per kg per day are suggested for bodybuilders (31) as a higher intake is proposed to sustain lean body mass (LBM), with sufficient carbohydrates and reduced fat intake (30,50,). Intense resistance training (alongside calorie restriction) can lead to a negative nitrogen balance (NNB) despite 2g/kg protein consumed (12,15).
Whey Protein For Intermittent Sports
A protein intake of 1.4-1.7g per kg per day is recommended for athletes undertaking activities which are intermittent in nature (45). This would include sports such as football or basketball.
Despite occasional allegations being made regarding negative effects of high whey protein consumption, there is a dearth of conclusive evidence to support such claims (32).
In fact claims regarding the impact on the health of the kidneys (40), bone density (39), liver (53) and cardiovascular system (33) have all been scientifically questioned or entirely disproven.
Take Home Message
Whey protein supplements give us the perfect opportunity to ensure our post activity protein metabolism remains in balance. They are a high quality protein source which is easily absorbed and provides all essential amino acids required to boost muscle protein synthesis and develop lean body mass.
Also, they are handily available in a variety of flavours to provide a quick hit of protein to supplement your daily protein dietary intake. No wonder they are one, if not the, most popular supplements around.
American Dietetic Association, Dietitians of Canada, American College of Sports Medicine, Rodriguez, N.R., Di Marco, N.M. & Langley S. (2009). American college of sports medicine position stand: Nutrition and athletic performance. Med Sci Sports Exerc. 41, 3, 709–31
Antonio J, Stout JR: Sports Supplements. Philadelphia, PA , Lippincott Williams & Wilkins; 2001.
Baty, J.J., Hwang, H., Ding, Z., Bernard, J.R., Wang, B., Kwon, B., et al. (2007). The effect of a carbohydrate and protein supplement on resistance exercise performance, hormonal response, and muscle damage. Journal of Strength and Conditioning Research, 21, 321–329.
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 1995, 268(3 Pt 1):E514-20.
Biolo G, Tipton KD, Klein S, Wolfe RR (1997) An abundant supply of amino acids enhances the metabolic effect of exercise on muscle protein. Am J Physiol 273(1 Pt 1):E122–E129
Bird, S.P., Tarpenning, K.M. and Marino, F.E. (2006). Liquid carbohydrate/essential amino acid ingestion during a short-term bout of resistance exercise suppresses myofibrillar protein degradation. Metabolism, 55, 570–577.
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 1997, 94:14930-14935
Borsheim E, Tipton KD, Wolf SE, and Wolfe RR. Essential amino acids and muscle protein recovery from resistance exercise. Am J Physiol Endocrinol Metab 283: E648–E657, 2002.
Bounous G, Batist G, Gold P: Immunoenhancing property of dietary whey protein in mice: role of glutathione. Clin Invest Med 1989, 12(3):154-161.
Bounous G, Kongshavn PA, Gold P: The immunoenhancing property of dietary whey protein concentrate. Clin Invest Med 1988, 11(4):271-278.
Burke DG, Chilibeck PD, Davidson KS, Candow DG, Farthing J, and Smith- Palmer T. The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength. Int J Sport Nutr Exerc Metab 11: 349–364, 2001.
Butterfield, G.E. (1987). Whole-body protein utilization in humans. Medicine and Science in Sports and Exercise, 19, S157–S165.
Campbell, B., Kreider, R.B., Ziegenfuss, T., La Bounty, P., Roberts, M., Burke, D., Landis, J., Lopez, H. and Antonio, J., 2007. Journal of the International Society of Sports Nutrition. Journal of the International Society of Sports Nutrition, 4(8), p.8.
Carunchia Whetstine ME, Croissant AE, Drake MA: Characterization of dried whey protein concentrate and isolate flavor. J Dairy Sci 2005, 88:3826-3839.
Celejowa, I. and Homa, M. (1970). Food intake, nitrogen and energy balance in Polish weight lifters, during a training camp. Nutrition and Metabolism, 12, 259–274.
Cermak NM, Res PT, de Groot LC, Saris WH, and van Loon LJ. Protein supplementation augments the adaptive response of skeletal muscle to resistancetype exercise training: A meta-analysis. Am J Clin Nutr 96: 1454–1464, 2012.
Churchward-Venne, T.A., Murphy, C.H., Longland, T.M. and Phillips, S.M., 2013. Role of protein and amino acids in promoting lean mass accretion with resistance exercise and attenuating lean mass loss during energy deficit in humans. Amino Acids, 45(2), pp.231-240
Cooke, M.B., Rybalka, E., Stathis, C.G., Cribb, P.J. and Hayes, A., 2010. Whey protein isolate attenuates strength decline after eccentrically-induced muscle damage in healthy individuals. J Int Soc Sports Nutr, 7(1), p.30.
Cribb PJ, Williams AD, Carey MF, and Hayes A. The effect of whey isolate and resistance training on strength, body composition, and plasma glutamine. Int J Sport Nutr Exerc Metab 16: 494–509, 2006.
Dangin M, Boirie Y, Guillet C, Beaufrere B: Influence of the protein digestion rate on protein turnover in young and elderly subjects. JNutr 2002, 132:3228S-33S.
el-Khoury AE, Forslund A, Olsson R, Branth S, Sjodin A, Andersson A, Atkinson A, Selvaraj A, Hambraeus L, and Young VR. Moderate exercise at energy balance does not affect 24-h leucine oxidation or nitrogen retention in healthy men. Am J Physiol 273: E394–E407, 1997.
Esmarck, B., Andersen, J.L., Olsen, S., Richter, E.A., Mizuno, M. and Kjaer, M. (2001). Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans. Journal of physiology, 535, 301–3.
Etzel MR: Manufacture and use of dairy protein fractions. J Nutr 2004, 134:996S-1002S.
Flakoll PJ, Judy T, Flinn K, Carr C, Flinn S: Postexercise protein supplementation improves health and muscle soreness during basic military training in Marine recruits. J Appl Physiol 2004, 96(3):951-956.
Friedman JE and Lemon PW. Effect of chronic endurance exercise on retention of dietary protein. Int J Sports Med 10: 118– 123, 1989.
Fujita, S., Dreyer, H.C., Drummond, M.J., Glynn, E.L., Volpi, E. and Rasmussen, BB. (2009). Essential amino acid and carbohydrate ingestion before resistance exercise does not enhance postexercise muscle protein synthesis. Journal of Applied Physiology2009, 106:1730–1739.
Gaine PC, Pikosky MA, Martin WF, Bolster DR, Maresh CM, Rodriguez NR: Level of dietary protein impacts whole body protein turnover in trained males at rest. Metabolism 2006, 55(4):501-507.
Ha E, Zemel MB: Functional properties of whey, whey components, and essential amino acids: mechanisms underlying health benefits for active people (review). J Nutr Biochem 2003, 14:251-258.
Hayes A and Cribb PJ. Effect of whey protein isolate on strength, body composition and muscle hypertrophy during resistance training. Curr Opin Clin Nutr Metab Care 11: 40–44, 2008.
Helms, E. R., Aragon, A. A., & Fitschen, P. J. (2014). Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr, 11(1), 20.
Helms, E.R., Zinn, C., Rowlands, D.S. and Brown, S.R., 2013. A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes. International Journal of Sports Nutrition Exerc Metab, 24, pp.127-38.
Hoffman, J.R. and Falvo, M.J., 2004. Protein-Which is best. Journal of Sports Science and Medicine, 3(3), pp.118-130.
Hu, F.B., Stampfer, M.J., Manson, J.E., Rimm, E., Colditz, G.A., Speizer, F.E., Hennekens, C.H. and Willett, W.C. (1999) Dietary protein and risk of ischemic heart disease in women. AmericanJournal of Clinical Nutrition 70, 221-227.
Hulmi, J.J., Lockwood, C.M. and Stout, J.R., 2010. Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein. Nutrition & metabolism, 7(1), p.1.
Institute of Medicine of the National Academies: Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids (macronutrients). Washington, DC , National Academies Press; 2002.
Joint Position Statement: nutrition and athletic performance. American College of Sports Medicine, American Dietetic Association, and Dietitians of Canada. Med Sci SportsExerc 2000, 32(12):2130-2145.
Katsanos CS, Chinkes DL, Paddon-Jones D, Zhang XJ, Aarsland A, Wolfe RR: Whey protein ingestion in elderly persons results in greater muscle protein accrual than ingestion of its constituent essential amino acid content. Nutr Res 2008, 28:651-658.
Kerksick, C., Harvey, T., Stout, J., Campbell, B., Wilborn, C., Kreider, R., Kalman, D., Ziegenfuss, T., Lopez, H., Landis, J. and Ivy, J.L., 2008. Journal of the International Society of Sports Nutrition. Journal of the International Society of Sports Nutrition, 5, 17.
Kerstetter JE, O’Brien KO, Caseria DM, Wall DE, Insogna KL:The impact of dietary protein on calcium absorption and kinetic measures of bone turnover in women. J Clin Endocrinol Metab2005, 90(1):26-31.
Knight EL, Stampfer MJ, Hankinson SE, Spiegelman D, Curhan GC: The impact of protein intake on renal function decline in women with normal renal function or mild renal insufficiency. Ann Intern Med 2003, 138(6):460-7
Krissansen GW: Emerging health properties of whey proteins and their clinical implications. J Am Coll Nutr 2007, 26:713S-23S.
Lemon PW, Tarnopolsky MA, MacDougall JD, and Atkinson SA. Protein requirements and muscle mass/strength changes during intensive training in novice bodybuilders. J Appl Physiol (1985) 73: 767 775, 1992.
Lemon PW: Beyond the zone: protein needs of active individuals. J Am Coll Nutr 2000, 19(5 Suppl):513S 521S
Lemon PW: Protein and amino acid needs of the strength athlete. Int J Sport Nutr 1991, 1(2):127-145.
Lemon PW: Protein requirements of soccer. J Sports Sci 1994, 12 Spec No:S17-22.
Levenhagen, D.K., Gresham, J.D., Carlson, M.G., Maron, D.J., Borel, M.J. and Flakoll, P.J. (2001). Postexercise nutrient intake timing in humans is critical to recovery of leg glucose and protein homeostasis. American Journal of Physiology: Endocrinology and Metabolism, 280, E982–E993
Manninen AH: Protein hydrolysates in sports nutrition. Nutr Metab (Lond) 2009, 6:38.
McLain, T.A., Escobar, K.A. and Kerksick, C.M., 2015. Protein Applications in Sports Nutrition—Part I: Requirements, Quality, Source, and Optimal Dose. Strength & Conditioning Journal, 37(2), pp.61-71.
Meredith CN, Zackin MJ, Frontera WR, Evans WJ: Dietary protein requirements and body protein metabolism in endurancetrained men. J Appl Physiol 1989, 66(6):2850-2856.
Mettler, S., Mitchell, N. and Tipton, K.D. (2010). Increased protein intake reduces lean body mass loss during weight loss in athletes. Medicine and Science in Sports and Exercise, 42, 326–337.
Miller SL, Tipton KD, Chinkes DL,Wolf SE, and Wolfe RR. Independent and combined effects of amino acids and glucose after resistance exercise. Med Sci Sports Exerc 35: 449–455, 2003.
Naclerio, F. and Larumbe-Zabala, E., 2016. Effects of Whey Protein Alone or as Part of a Multi ingredient Formulation on Strength, Fat-Free Mass, or Lean Body Mass in Resistance-Trained Individuals: A Meta-analysis. Sports Medicine, 46(1), pp.125-137.
Navder, K.P. and Lieber, C.S. (2003b) Nutrition and alcoholism. In: Nutritional Aspects and ClinicalManagement of Chronic Disorders and Diseases. Ed: Bronner, F. Boca Raton, FL: CRC Press. 307- 320
Phillips SM, Hartman JW, Wilkinson SB (2005) Dietary protein to support anabolism with resistance exercise in young men. J Am Coll Nutr 24(2):134S–139S
Phillips SM, Parise G, Roy BD, Tipton KD, Wolfe RR, Tamopolsky MA: Resistance-training-induced adaptations in skeletal muscle protein turnover in the fed state. Can J Physiol Pharmacol 2002, 80(11):1045-1053.
Phillips SM, Tang JE, and Moore DR. The role of milk- and soy-based protein in support of muscle protein synthesis and muscle protein accretion in young and elderly persons. J Am Coll Nutr 28: 343– 354, 2009.
Phillips SM. (2004). Protein requirements and supplementation in strength sports. Nutrition, 20, 689-695.
Phillips, S.M. and Van Loon, L.J. (2011). Dietary protein for athletes: from requirements to optimum adaptation. Journal of Sports Science, 29 (Suppl 1), S29–S38.
Rasmussen BB, Tipton KD, Miller SL, Wolf SE, and Wolfe RR. An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise. J Appl Physiol (1985) 88: 386–392, 2000.
Rennie MJ, Bohe J, Smith K, Wackerhage H, Greenhaff P: Branchedchain amino acids as fuels and anabolic signals in human muscle. J Nutr 2006, 136(1 Suppl):264S-8S.
Rieu I, Balage M, Sornet C, Debras E, Ripes S, Rochon-Bonhomme C, Pouyet C, Grizard J, Dardevet D: Increased availability of leucine with leucine-rich whey proteins improves postprandial muscle protein synthesis in aging rats. Nutrition 2007, 23:323-331
Rodriguez NR, Vislocky LM, Gaine PC: Dietary protein, endurance exercise, and human skeletal-muscle protein turnover. Curr Opin Clin Nutr Metab Care 2007, 10(1):40-45.
Rondanelli, M., Klersy, C., Terracol, G., Talluri, J., Maugeri, R., Guido, D., Faliva, M.A., Solerte, B.S., Fioravanti, M., Lukaski, H. and Perna, S., 2016. Whey protein, amino acids, and vitamin D supplementation with physical activity increases fat-free mass and strength, functionality, and quality of life and decreases inflammation in sarcopenic elderly. The American journal of clinical nutrition, 103(3), pp.830-840.
Schaafsma, G., 2000. The protein digestibility–corrected amino acid score. The Journal of nutrition, 130(7), pp.1865S-1867S.
Slater, G. and Phillips, SM. (2011). Nutrition guidelines for strength sports: sprinting, weightlifting, throwing events, and bodybuilding. Journal of Sports Science, 29, S67–S77.
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 1998, 275:E73-8.
Tang JE, Moore DR, Kujbida GW, Tarnopolsky MA, and Phillips SM. Ingestion of whey hydrolysate, casein, or soy protein isolate: Effects on mixed muscle protein synthesis at rest and following resistance exercise in young men. J Appl Physiol (1985) 107: 987–992, 2009.
Tarnopolsky M: Protein requirements for endurance athletes. Nutrition 2004, 20(7-8):662-668.
Tarnopolsky MA, Atkinson SA, MacDougall JD, Chesley A, Phillips S, and Schwarcz HP. Evaluation of protein requirements for trained strength athletes. J Appl Physiol (1985) 73: 1986–1995, 1992.
Tarnopolsky MA, MacDougall JD, and Atkinson SA. Influence of protein intake and training status on nitrogen balance and lean body mass. J Appl Physiol 64: 187–193, 1988.
Tarnopolsky, M.A. (2008). Building muscle: nutrition to maximize bulk and strength adaptations to resistance exercise training. European Journal of Sport Science, 8, 67–76
Taylor IV, L.W., Wilborn, C., Roberts, M.D., White, A. and Dugan, K., 2015. Eight weeks of pre-and post exercise whey protein supplementation increases lean body mass and improves performance in Division III collegiate female basketball players. Applied Physiology, Nutrition, and Metabolism, (ja).
Tipton KD, Elliott TA, Cree MG, Wolf SE, Sanford AP, and 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, and Wolfe RR. Postexercise net protein synthesis in human muscle from orally administered amino acids. Am J Physiol 276: E628–E634, 1999
Tipton, K.D. (2008). Protein for adaptations to exercise training. European Journal of Sports Science, 8, 107–118.
Tipton, K.D. and Wolfe, R.R. (2004). Protein and amino acids for athletes. Journal of Sports Science, 22, 65-79.
Tipton, K.D., Elliott, T.A., Cree, M.G., Aarsland, A.A., Sanford, A.P., Wolfe, R.R. (2007). Stimulation of net muscle protein synthesis by whey protein ingestion before and after exercise. American Journal of Physiology: Endocrinology and Metabolism, 292, E71–E76.
Tipton, K.D., Rasmussen, B.B., Miller, S.L., Wolf, S.E., Owens-Stovall, S.K., Petrini, B.E. et al. (2001). Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. American Journal of Physiology: Endocrinology and Metabolism, 281, E197–E206.
Wells, G.D., 2009. The Post-Workout Protein Puzzle: Which Protein Packs the Most Punch?. Strength & Conditioning Journal, 31(1), pp.27-30.
Wilson, J. and Wilson, G.J. (2006). Contemporary issues in protein requirements and consumption for resistance trained athletes. Journal of the International Society of Sports Nutrition, 3, 7–27.
Yang Y, Jemiolo B, Trappe S: Proteolytic mRNA expression in response to acute resistance exercise in human single skeletal muscle fibers. J Appl Physiol 2006, 101(5):1442-1450.
What Is Whey Protein? | Benefits, Side Effects & Dosage