That would be whey better than leucine. Supplement companies aren’t going to like me.
Whey protein or leucine post-workout to increase muscle protein synthesis (MPS)? The Phillips group just published an article trying to answer this question.
Introduction: You all are probably aware that ingesting amino acids stimulates an increase in muscle protein synthesis even without resistance training. Leucine has been toted to best stimulate MPS by activating components of a signalling cascade known as mTOR. There is still controversy though as to whether or not leucine can enhance MPS following leucine infusion or by simply adding more of it to a post-workout protein drink. This group previously reported the the optimal dose of protein post-workout to stimulate MPS was 20g and that anything below this is not sufficient and anything above this number (40g) does not increase MPS further. Therefore, the aim of this study was to see if taking a “sub-optimal” dose of whey (6.25g with approximately 0.75g of leucine) protein and supplementing it with leucine or a mixture of essential amino acids without leucine would have an effect on MPS at rest and after acute resistance training. This will be compared to a dose of whey (25g with approximately 3.0g of leucine) which is sufficient to induce maximal stimulation of MPS after resistance exercise.
Methods: Twenty-four adult males were randomized to one of three groups that either ingested a whey protein drink, a leucine drink, or an essential amino acid drink. Prior to ingestion, the volunteers completed an acute bout of unilateral resistance exercise (knee extensions). Muscle biopsies were taken at the time of ingestion and at time points 1 hour, 3 hours, and 5 hours post-exercise.
Results: After whey protein ingestion, blood leucine, branch-chain amino acids, essential amino acids, and total amino acids were all highest as compared to the groups that ingested leucine or EAA (without leucine). Blood leucine was only higher initially after ingesting the leucine drink but stayed elevated longer by ingesting whey. Rates of MPS remained increased for 3-5 hours at exercise recovery above those volunteers who did not ingest anything, versus the groups who ingested leucine or the EAA drink.
Discussion: A dose of whey protein that has been previously shown to be less than maximally effective to stimulate MPS after resistance exercise, when supplemented with leucine, resulted in an early (1-3 hour post-exercise recovery) increase in rates of MPS equal to that of ingesting 25g of whey. Also, the same was found by supplementing a low dose of whey with essential amino acids void of leucine. However, MPS was sustained longer (3-5 hours post-exercise) only with the group that ingested whey protein. These differences occurred despite the fact that blood amino acid levels returned to baseline after 3-5 hours but MPS still continued. Therefore, the authors state that peak activation of MPS does not appear to be driven by increasing leucine in the blood and that amino acid transport across the sarcolemma (plasma membrance of the muscle cell) and intracellular amino acid availability may be important in the regulation of MPS.
Conclusion: Leucine stimulates MPS post-exercise equal to that of whey protein, despite only containing 45% of the total EAA content of the whey. However, similar increases in MPS were observed in the EAA ingestion group that did not contain leucine. Thus, the authors speculate that in young healthy individuals, the leucine content provided by approximately 6.25g (approximately 0.75g of leucine) of whey protein seems adequate to maximally stimulate MPS if sufficient amounts if the other EAA are provided (approximately 8.5g EAA). Also, the whey protein ingestion group was the only group that sustained MPS 3-5 hours post-exercise.
My input/practicality: What if I were to tell you I can make a 1lb bag of whey protein last me 3 months? Well I can, and I do, and I’ve been doing it for years. I only use a half scoop of whey protein post-exercise. Never a full scoop. Never a “heaping” scoop. Why do you even think they use the word heaping? It’s all about the dolla dolla bill y’all. This study shows that only 6.25g of whey is necessary to maximally stimulate protein synthesis as long as it contains approximately 750mg of leucine and 8.5g of the other 8 essential amino acids (which are histidine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine). Make sure you check on the labels of your favorite whey protein because it usually lists the amount of leucine and the other essential amino acids on it. One scoop of whey is usually on average around 20g of protein so if you use a half scoop like me it is around 10g (still a little over from what this study suggests). Supplement companies are going to hate this study (like they read them anyways) as well as me for posting this but you’ll love it/me for saving you money.
Churchward-Venne et al J Physiol. 2012 Mar 25.