We talk a lot about protein and amino acids, but that’s only because they are the nutrients required for recovery and additional protein growth. To stimulate growth, optimal amounts of the amino acids are a prerequisite, particularly the essential amino acids. While studies have illustrated that only the essential amino acids are needed to stimulate growth of muscle proteins[1, 2], common whole protein sources such as beef, chicken, but more importantly whey, also contain the nonessential amino acids. In fact, in a high quality whey protein supplement, approximately 50% of the protein is made up of the nonessential amino acids. For these reasons, some people might ask the question, “why should I keep taking these other ‘useless’ amino acids?” I’m going to just start taking the essential amino acids in capsule or powder form. While this seemingly is solid logic, a recent study provided evidence that the power of whey protein may extend beyond the essential amino acids found within it . In this study, healthy adults were given either 15 grams of a whey protein or 6.72 grams of the essential amino acids, or the same amount of the essential amino acids found in a 15 gram dose of whey protein. After ingestion, a series of highly technical measures were completed involving a series of blood draws and muscle biopsies to determine the extent to which amino acid levels changed both in the blood and in the muscle. Interestingly, peak concentrations of amino acids increased in the blood after just 30 minutes similar in both groups . This information alone is valuable and convincing because for starters it reinforces the fact that digestion of whey protein occurs very rapidly. Think about it for a second, only 30 minutes for your body to transport nutrients from your mouth, through your stomach, into your intestines and into the blood within this time period. Once in the blood, it’s on a one-way ticket to your working muscles to rebuild and recovery (to be fair or other tissues that may need repair as well). Using sophisticated measuring systems, the researchers concluded that the amount of protein accrued in the muscle from ingestion was greater after ingesting the whey protein. Put in other words, ingestion of 15 grams of a whey protein increased protein building more than the same amount of the amino acids required to complete this process. How can this happen? They should be the same, right?
To be honest, the researchers aren’t really absolutely sure why this is. They suggested that other components of the whey protein may have supported a greater increase in insulin, a key hormone produced by our body that is closely associated with increases in muscle protein growth. Additionally, the authors also suggested that the complete source of whey protein would also contain greater amount of three important components: cysteine, β-lactoglobulin and α-lactalbumin [4-7]. Adequate amounts of cysteine are required to support optimal production and functioning of the largest system of antioxidants, the glutathione system. While this certainly doesn’t explain the greater protein development, it is a key point to consider in favor of knocking back your post workout whey protein isolate powder. Additionally, β-lactoglobulin and α-lactalbumin, are two key bioactive fractions that operate effectively to modulate immune function. While this doesn’t explain greater protein balance, enhancement of the immune system from taking a high quality whey protein is also a key factor in favor of consuming the whole source.
A few points, however, need to be clarified for how findings from this article should be interpreted. For starters, the dose of whey protein provided was low. A 15 gram dose of whey protein is not a typical dose consumed by the average resistance training individual. In this respect, most people will ingest somewhere in the range of 25 to 50 grams of whey protein in each dose. Dose response effects of ingesting greater amounts of the amino acids are known to occur, but it is possible that as greater amounts of the amino acids are ingested that the findings may change simply because with a greater amount of protein, the ability of the body to digest, transport, absorb, etc. may not be able to act at the same capacity. Additionally, it’s important to realize that delivery of the essential amino acids worked VERY WELL and thinking that ingesting capsules or powder forms of essential amino acids was not worthwhile or effective is the absolute last frame of mind to develop…it’s all about timing with these types of supplements. They can be a life saver when caught between meals and in a pinch! At best, you can be rest assured that maximal delivery of the ever-important essential amino acids can rapidly (within 30 minutes) occur if a single 15 gram dose of whey protein occurs or if a 6-7 grams dose of essential amino acids are provided. While greater amounts of muscle protein was accrued after ingesting the dose of whey protein, the reason for this finding isn’t absolutely certain (rest assured I am going to keep my eye out for some research that will help clarify this…which is undoubtedly coming down the research pipe line). Ingesting a whole protein source such as whey has additional components that certainly do warrant mentioning of which include optimal levels of important amino acids to help strengthen the antioxidant system in the body as well as key bioactive fractions that help support immune function.
- Tipton, K.D., B.E. Gurkin, S. Matin, and R.R. Wolfe, Nonessential amino acids are not necessary to stimulate net muscle protein synthesis in healthy volunteers. J Nutr Biochem, 1999. 10(2): p. 89-95.
- Volpi, E., H. Kobayashi, M. Sheffield-Moore, B. Mittendorfer, and R.R. Wolfe, 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(2): p. 250-8.
- Katsanos, C.S., D.L. Chinkes, D. Paddon-Jones, X.J. Zhang, A. Aarsland, and R.R. Wolfe, 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(10): p. 651-8.
- Ha, E. and M.B. Zemel, Functional properties of whey, whey components, and essential amino acids: mechanisms underlying health benefits for active people (review). J Nutr Biochem, 2003. 14(5): p. 251-8.
- Krissansen, G.W., Emerging health properties of whey proteins and their clinical implications. J Am Coll Nutr, 2007. 26(6): p. 713S-23S.
- Walzem, R.L., C.J. Dillard, and J.B. German, Whey components: millennia of evolution create functionalities for mammalian nutrition: what we know and what we may be overlooking. Crit Rev Food Sci Nutr, 2002. 42(4): p. 353-75.
- Yalcin, A.S., Emerging therapeutic potential of whey proteins and peptides. Curr Pharm Des, 2006. 12(13): p. 1637-43.