A very important study was just published regarding optimal protein intake and amino acid usage between meals in order to optimize skeletal muscle protein synthesis.
For you scientific types here is a link to the actual study data.
Here is a laymen's version of the data If you want, take the time to read and discuss it!
This is a very important study for athletes that supplement with protein. You can take away these points from the study.
1. Eat big! Larger meals are more optimal for skeletal muscle protein synthesis (growth) than having many small meals. Protein synthesis will become refractory to constantly elevated levels of amino acids. Now, I am not in any way shape or form implying that athletes are better off just consuming one large protein meal per day. What I am implying is that it is better to consume larger protein doses spaced further apart and maximize protein synthesis, rather than consuming smaller doses of protein throughout the day, since research has shown that protein synthesis will become refractory to constantly elevated levels of amino acids. It may be that a period where amino acids return to baseline or near baseline is required in order to initiate another bout of protein synthesis. I therefore suggest that one consume 4-6 larger protein doses per day instead of 6-8 meals and wait 4-5 hours between meals
rather than 2-3 hours.
2. Supplementing with leucine (amino acids) along with carbohydrate between said meals will help to keep protein synthesis turnover without causing as large of a diminishing return. So in between meals is a great time to supplement with BCAA's for optimal growth.
Now I will be the first to admit that the research is just not specific or broad enough to address the size and frequency issue with absolute certainty; but I believe these recommendations are a good general starting point. What is clear from this study is that certain protein sources have a stronger impact on protein synthesis than others, and also it appears that keeping amino acids constantly elevated by smaller protein doses throughout the day may NOT be optimal. Hopefully future research will address more specifics with regards to these issues.