T Nation

Evidence for Protein Supplementation


#1

Hello everyone,

I am new to this forum but have heard great things. I am a physical therapist and have had a lot of questions regarding protein supplementation through the last few years and therefore decided to get more knowledge on the area. Now what I normally do in this situation is find a bunch of articles and give them a thorough read through and try to draw a conclusion based on this, in hopes that I can come with an informed and evidence based answer for my patients.

I must admit that in this case I was a bit biased as the theory to protein supplementation is very sound and I was convinced that finding concrete evidence for this would be a simple task.

I have now been looking about a bit for evidence and have thus far found an abundance of evidence that protein supplementation does not in fact help muscle cross sectional size and/or performance.

I would like anyone who has some evidence to counter this to please indicate it to me if at all possible.

Don't get me wrong I don't want people to post their opinions, or "what works for me". I would really like some solid evidence preferably peer reviewed double blind studies. I would really appreciate it.

Here are a few article that people may find interesting that state that protein supplementation has no noticeable effect.

"Efficacy of Whey Protein Supplementation on Resistance Exercise-Induced Changes in Lean Mass, Muscle Strength, and Physical Function in Mobility-Limited Older Adults."
Chalé A, Cloutier GJ, Hau C, Phillips EM, Dallal GE, Fielding RA

"Whey protein does not enhance the adaptations to elbow flexor resistance training."
Erskine RM, Fletcher G, Hanson B, Folland JP.

"Muscle Performance, Size, And Safety Responses After Eight Weeks Of Resistance Training And Protein Supplementation: A Randomized, Double-Blinded, Placebo-Controlled Clinical Trial."
Walter AA, Herda TJ, Costa PB, Ryan ED, Stout JR, Cramer JT.

Thank you very much for reading and I hope to hear from someone!

Regards,

Siin


#2

It's important to view studies from the standpoint of "what did they actually examine?" and "what were they capable of measuring?" rather than immediately applying as a generalization. Which I'm not saying you did, of course.

Here's the first:

So, a group of 70-85 year olds received a total of 40 g whey protein per day, which isn't very much, and further was not an addition to an existing diet but a substitute for an isocaloric amount of composition not specified in the abstract, and underwent resistance training.

The measured average increase in muscle cross sectional area was somewhat greater for the WPC group: a person training with weights would probably rather experience a 4.6% increase than a 2.9% increase; for example, wouldn't we rather gain 16 lb over a course of time rather than 10 lb simply from adding one serving of whey per day? This is the same percentage difference, not that I'm saying that one can expect that.

But, the study was not statistically capable of resolving differences that "small," so therefore it is reported as being no result.

It does show something, not a great deal, but something, about what happens when you give 40 g/day whey protein to the elderly undergoing resistance training. It shows that they don't Hulk out, for example. The general applicability of the data is zero, when considering carefully what was looked at and what they were able to measure.

So, previously untrained young men were studied over a very short period of time. This group can gain muscle very rapidly almost regardless of nutritional status, with very high variability between individuals.

This study is sort of like trying to determine whether a particular VP Racing gasoline, say one designed for turbocharged engines, can produce more power than pump gas by enlisting a bunch of novice drivers, putting them in a widely varying fleet of rental cars, and seeing who can drive across New York City in rush hour the fastest. The gasoline is not what's going to make the difference.

Anyway, in terms of the results, the variability -- the plus and minus figures -- was so great that there could have been substantial differences in this group in terms of whether each individual would have done substantially better on one protocol versus the other, but not statistically detectable in terms of average. With high variability, it could be that one group happened to have more naturally-higher-gainers assigned to it than the other, with no way of knowing whether that happened but only a means of calculating the probability that it might have happened, and therefore nothing could be detected.

It always, in my opinion, would be good if they put into at least the article or preferably even the abstract how small an effect they would have been able to detect. This would save a lot of time for the reader. If seeing right away that even, for example, a 5 lb difference in muscle gain would have been "statistically insignificant" in a given study, then it could be ignored right away, instead of having to grind numbers oneself to find that out, or having to estimate by eye from the plus-or-minus numbers. But authors don't like to put out there directly just how little detection ability their study had. Almost never is this directly admitted.

I'd have to purchase the article to find the actual results and variabilities, which are not given in the abstract, but the situation is likely the same as the above study.

In general, it's an entirely different question whether an individual who has trained consistently and well for years and has reached a point of tending to stabilize at a given amount of LBM with further gains being difficult and slow, versus individuals as in the above studies. The former situation is easily personally evaluated, but difficult to do scientifically, and rarely if ever done. While it would be nice to find a study that even tries to look at that, I haven't seen where it's even been tried.

Attempted extrapolations to serous weight training from the elderly, or the untrained or typical (which is a low standard with regards to quality and consistency of training) college student getting one shake a day and so forth, will not necessarily be reliable.

Further, with regard to where many have discovered that one can personally observe differences, it's not from, for example, taking 40 g whey protein in a shake instead of having it in a meal. It's principally from protein shakes allowing substantially greater protein intake where the intake wasn't particularly high in the first place and/or substantially greater caloric intake than what the individual in fact does without the shakes. It's by no means a magic bullet where a relatively small amount does big things in a short time. Any study that could only detect such a thing will turn up nothing "to statistical significance."


#3

Thank you very much for your thorough answer. I linked those 3 articles but there are very many and I agree they do look at "niche" areas of study to say the least.

I have been using whey protein myself now for 3 weeks and intend to continue doing so for a few months to try and get my own perspective on the matter. I train 6 times a week and have now included only a shake (20g) after each work out to see if I notice a difference. not only in growth but also in my appetite.

I just want to be able to give my patients sound advice on this matter and I dont seem to be able to come up with solid evidence to back up my arguments one way or another. Perhaps my own experience with it will teach me something.

Thank you once again for the answer it helps a great deal.


#4

You're very welcome!

In many cases, the best reason for an individual to use it is not that it's impossible to get a comparably good result or similar daily macronutrient totals with only whole foods, but because protein powder doesn't carry much carbs or fat along with it and is consumed very easily. This makes it very easy to make some kinds of desired changes that otherwise might be hard or might not get done.

If a person can get a dietary improvement in macronutrient balance and/or caloric intake in a convenient way, and another harder way just wouldn't get done, then there's a lot to be said for the convenient way that does get done.

With regard to whey protein, this really may be the most important practical factor for most, at least as personal opinion. There can be benefits from the quality of the protein as well, and immune benefits, but that's not as big a factor as what can occur practically from changed macronutrient intake.


#5

Excellent response Bill.

I wouldn't think 20g or PRO post workout would make much difference. Not only is it not much, but it is also not even a noticeable calorie increase.


#6

I suspect this is the case. I was taught at least .25 per/lb of bodyweight.


#7

I don't think that protein supplementation is that straight forward. What population are you focusing on? 70 year old knee replacements? 16 year old ACL tears? Etc.
Finding evidence is tough because its just protein. By that I mean if the subject is taking in enough protein via whole foods then the supplement may be unnecessary, but if the subjects are unable to take in adequate protein then supplementing with whey would probably be useful. Making a study designed to gauge the usefulness of whey vs whole foods with equal overall macronutrient intake is extremely difficult because that would require a large group with extremely good compliance for a long time period. The fact of the matter is that you can't get a lot of dedicated lifters to track macros consistently for a long period.

Tldr: not realistic to study whey vs whole foods... Too many confounding variables.

Conclusion: if your patients are getting adequate pro via whole foods then whey might not be needed, but it sure is convenient.