25g Whey Protein or 10g of EAAs Maximize Post Workout Protein Synthesis Without Additional Carbs

While this probably won't end the debate on whether post-workout carbohydrate intake is a good or a bad thing, a recent review of the literature presented by Steward M. Phillips at the The Summer Meeting of the Nutrition Society (Phillips. 2010) suggests that the addition of carbs to your post-workout shake is at least unnecessary, as long as you have a sufficient amount of leucine and EAAs in it:

The increment in [muscle protein synthesis] MPS is maximally stimulated at a dose of protein of approximately 25 g or 10 g EAA. This rise is based solely on protein consumption and is not augmented by carbohydrate, at least when protein is adequate.

Also, the type of protein is of utmost importance. Phillips recommends whey protein or (please note that it is not whey and EAAs) a blend of EAAs at dosages of 25g and 10g, respectively.

Figure 1: Whole blood leucine concentration (μM) following resistance exercise from subjects who consumed 500 ml fluid skim (low fat) milk and an isonitrogenous and isoenergetic quantity of a soya drink (drawn with data from Wilkinson et al.).

As can be seen from figure 1, even skimmed milk, which is only partially whey, produces a larger increase in whole blood leucine than soy protein (soy is for girls only, anyway ;-) Consequently, you should prefer dairy proteins or whey concentrates, isolates or hydrosolates as your post workout protein sources.