http://www.ncbi.nlm.nih.gov/entrez/q...=pubmed_docsum
The bolded part seems to indicate that peaking amino acid levels fairly frequently would be better for protein synthesis than having constant levels of amino acids. Thoughs?? The entire study is free to read at this adressRegulation of muscle protein by amino acids.
Wolfe RR.
University of Texas Medical Branch and Shriners Burns Hospital, Department of Surgery, Galveston 77550, USA. [email protected]
Amino acid availability is a potent regulator of muscle protein synthesis (MPS). We have performed a series of studies using stable isotope methodology and the arteriovenous balance approach to quantify many aspects of the response of MPS, breakdown, and the balance between synthesis and breakdown to changes in the availability of amino acids. A constant intake of amino acids stimulates MPS in a dose-dependent manner until concentrations are approximately doubled, after which further increases in concentration are ineffective. MPS rises more rapidly after bolus ingestion to a peak rate of MPS higher than during constant intake, but the response is transient. A reduction in amino acid availability below basal levels inhibits MPS. Ingestion of nonessential amino acids is not needed to stimulate MPS. When carbohydrate alone is ingested there is minimal effect on MPS, but there is an interactive effect with amino acid ingestion, meaning the response to amino acids plus glucose is more than the sum of their individual effects. Finally, acute anabolic responses in net MPS correspond quantitatively to differences in 24-h net muscle balances
Regulation of Muscle Protein by Amino Acids
http://jn.nutrition.org/cgi/content/full/132/10/3219S
The bolded and red shows though that a peak is not enough to sustain muscle synthesis for a longer period. But maby a peak followed by sustained levels are superior to only sustained levels?Bolus versus constant infusion
The response of MPS to a bolus of amino acids is quite different from the response to a constant infusion. There is a rapid increase in MPS in conjunction with the rise in EAA concentration, and an equally rapid fall as the EAA concentrations begin to decrease (Fig. 3 ). However, the rate of MPS returned to the basal value well before the concentration fell to the basal level. In fact, in the example shown in Figure 3 , after ingestion of 15 g of EAA, net balance (as well as the rate of MPS) had returned to the basal rate when the plasma concentration was still more than double the basal value. In contrast, when plasma concentrations were increased to a steady-state concentration for 3 h at a value twice above the basal value, the maximal stimulation of MPS was achieved (17 ). Furthermore, whereas the response to a bolus is transient, the peak response may be 6- to 10-fold the basal value. Nonetheless, because of the transient nature of the response, the total synthetic response (area under curve of synthesis vs. time) was less than when similar doses of amino acids were taken in the constant intake mode as opposed to the bolus ingestion (Fig. 4 ). Thus, different mechanisms appear to be operative in response to the mode of ingestion. Clarification of these mechanisms could lead to amplifying the response to a given amount of intake.
That would mean that drinking a whey shake before a solid meal for instance would be more anabolic than just eating the meal.
Thoughs?
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Originally Posted by novastepp
