1. "Our results have some relevance to the question of the requirement of the human body for protein. They suggest that quite modest increases in amino acid supply, within the diurnal concentration range, result in substantial changes in the rates of synthesis, and thus probably the deposition of protein in muscle. Together with our previous results showing that stimulation of MPS is time limited (Bohé et al. 2001), it appears that only modest amounts of dietary amino acids would be needed to achieve maximal stimulation of the muscle anabolic processes (i.e. for adults of average weight, 55-75 kg 0.260 mg kg-1 h-1 2 h, or of the order of 30-40 g of protein). This is probably somewhat lower than the current FAO/WHO/UNU recommendation of 0.8 g kg-1 day-1 and much lower than that of 1.2 g kg -1day-1 proposed by some workers for the elderly (Campbell et al. 2001). The current results could have important implications for deciding upon protein requirements in circumstances in which the availability of protein is limited."

J Physiol (2003), 552.1, pp. 315-324; Human muscle protein synthesis is modulated by extracellular, not intramuscular amino acid availability: a dose-response study

Fulltext: http://jp.physoc.org/cgi/content/full/552/1/315


2. "The major findings of this study are that a square-wave increase in the availability of plasma amino acids took between 30 min and 1 h to have any measurable effect on muscle protein synthesis... before falling to a value not significantly different from the basal value for the succeeding 4 h.

Overfeeding protein does not increase the size of the lean body mass, and amino acids supplied in excess of the requirements of protein synthesis are simply oxidized and their carbon skeletons used for fuel or stored as fat.

During a normal day, the extent of fed state accretion of muscle protein may become limited by an inhibitory mechanism (as yet unknown) whenever the substrate requirement for protein synthesis is exceeded."

Journal of Physiology (2001), 532.2, pp. 575-579; Latency and duration of stimulation of human muscle protein synthesis during continuous infusion of amino acids

Fulltext: http://jp.physoc.org/cgi/content/ful...ee7396b14d77cd

Our purpose was to assess muscular adaptations during 6 weeks of resistance training in 36 males randomly assigned to supplementation with whey protein (W; 1.2 g/kg/day), whey protein and creatine monohydrate (WC; 0.1 g/kg/day), or placebo (P; 1.2 g/kg/day maltodextrin). Measures included lean tissue mass by dual energy x-ray absorptiometry, bench press and squat strength (1-repetition maximum), and knee extension/flexion peak torque. Lean tissue mass increased to a greater extent with training in WC compared to the other groups, and in the W compared to the P group (p < .05). Bench press strength increased to a greater extent for WC compared to W and P (p < .05). Knee extension peak torque increased with training for WC and W (p < .05), but not for P. All other measures increased to a similar extent across groups. Continued training without supplementation for an additional 6 weeks resulted in maintenance of strength and lean tissue mass in all groups. Males that supplemented with whey protein while resistance training demonstrated greater improvement in knee extension peak torque and lean tissue mass than males engaged in training alone. Males that supplemented with a combination of whey protein and creatine had greater increases in lean tissue mass and bench press than those who supplemented with only whey protein or placebo. However, not all strength measures were improved with supplementation, since subjects who supplemented with creatine and/or whey protein had similar increases in squat strength and knee flexion peak torque compared to subjects who received placebo."

Int J Sport Nutr Exerc Metab. 2001 Sep;11(3):349-64.; The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength

http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Citation