Dr. Lemon: Exactly. Their protein synthesis rate was higher at the 1.4 pg/k level. This would indicate 1.4 pg/k was closer to what they need to consume than the .9 pg/k, which has been the universal recommendation. So this would clearly suggest that if you consume the current recommendation and you're a bodybuilder, your results are going to be sub-optimal.
MM: What happened when the consumption went from 1.4 pg/k to 2.4 pg/k?
Dr. Lemon: That's really interesting, because protein synthesis did not increase further. This suggests that at least in that population, the 2.4 pg/k exceeded the optimal amount of protein. So, we concluded that somewhere between 1.4 pg/k and 2.4g/k would be optimal. That fits in with some of the other work we've done with other measures, such as the nitrogen balance technique that indicates an intake of about 1.6 pg/k to 1.7 pg/k is optimal. If that's all correct ---and you'll get a debate from some people because some of this work is fairly new ---then it means that bodybuilders may be correct in their interpretation that their protein needs are higher, but they're not as high as they think they are. As you mentioned earlier, many of them consume diets in excess of 2 grams per kilogram, which would appear to be excessive.
Everybody ought to read this article:
http://maxmag.maxsportsinternational.com/healthnutrition/issue12/12hn1.htm
Dr. Lemon: You have to remember that this response may be linear, as many bodybuilders assume. Increasing dietary protein may improve muscle growth up to some point, and then there may be a ceiling point or plateau. Beyond that there may actually be some adverse effects. I know what you mean: if 1.6 pg/k or 1/.7 pg/k is good, then 2.5 pg/k or 3.0 pg/k must be better. Right? In fact, it may not be. It may be good to go from .9 pg/k to 1.8 pg/k or so ---whatever that optimum is ---but after that there may be no more gain, with this possible exception: Unless you're ingesting another anabolic agent that may allow you to benefit from more protein. But we have not done those types of studies.