The conventional wisdom is that 20-25 g of Protein is optimal at a meal for Protein Muscle Synthesis has been challenged by a recent study. Turns out that most of the previous studies looked at exercise of isolated muscle groups rather than whole body resistance exercise.
The study (Physiol Rep. 2016 Aug; 4(15): e12893. The response of muscle protein synthesis following whole‐body resistance exercise is greater following 40 g than 20 g of ingested whey protein. Lindsay S. Macnaughton, Sophie L. Wardle, Oliver C. Witard, Chris McGlory, D. Lee Hamilton, Stewart Jeromson, Clare E. Lawrence, Gareth A. Wallis, and Kevin D. Tipton) took a look at how much Protein is optimal at a meal after larger muscle group exercise. The conclusion?