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Protein Timing

Bigtex

Bigtex

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Aug 14, 2012
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This study was designed to investigate whether a whey protein blend supplement before and after resistance exercise for 12 weeks would be effective in increasing muscular function when compared to a placebo group that had a higher total protein intake. The Protein group (PRO) only took in the Korean RDA of 65g/d. The placebo group (PLA) took in equal amounts up until week 8 and then started increasing the intake daily. Protein supplements were only give on training days.

Richard Kreider, Yeram Park, Hun-Young Park, Jisu Kim, Kiwon Lim. Effects of whey protein supplementation prior to, and following, resistance exercise on body composition and training responses: A randomized double-blind placebo-controlled study. J Exerc Nutrition Biochem. 2018;22(2):007-011.

Abstract and figures

Purpose: The composition of protein supplements, the consumption timing immedi¬ately before and after resistance exercise training (RET), and the quantity of protein supplementation may be important factors for the im-provement of muscle mass and function. Although these factors should be considered comprehensively for effective improvement of muscular function in protein supplementation, relatively few studies have focused on this area. Therefore, this study was designed to investigate whether a protein blend supplement before and after resistance exercise for 12 weeks would be effective in increasing muscular function.

Methods: In total, 18 participants were randomly assigned to a placebo (PLA) or protein blend supplement (PRO) group. All subjects followed the same training routine 3 times per week for 12 weeks, taking placebo or protein supplements immediately before and after each exercise session. The protein supplement consisted of 40 g of blend protein, including hydrolyzed whey protein. The RET consisted of lower body (barbell squat, dead lift, seated leg extension, and lying leg curl) and upper body (bench press, barbell rowing, preacher bench biceps curl, and dumbbell shoulder press) exercises. A repetition was defined as three sets of 10-12 times with 80% of one repetition maximum (1RM).

Results: Although the PRO group had a lower protein intake in terms of total food intake than the PLA group, the mean changes in muscle circumference, strength, and exercise volume increased, especially at week 12, compared to the PLA group.

Conclusion: These results suggest that the composition and timing of protein intake are more important than the total amount.

One thing this study pointed out was that either before or after training whey protein intakes are needed to help stimulate hypertrophy. The minimum amount needed is 20g to stimulate synthesis. The same effect can be obtained by using a minimum of 5g of BCCA, at least 1g of creatine adds even more of a benefit.

So after 12 weeks the PRO group had greater improvement in muscle hypertrophy, function, circumference, strength, and endurance that the PLA group. The protein supplementation before and after training seemed to provide greater effects than a slightly higher total protein intake due to dietary timing. They also noted that ingesting whey protein before and after is more effective that just ingesting it either before or after. More especially in trained athletes.

Some other interesting ideas......when protein works so well around training because 1) it digest quickly and flood the blood with amino acids 2) is had more leucine than any other protein.

Protein supplementation also was show to increase anabolic hormone responses. I would like to see this repeated adding another group that is taking in a very high protein diet and see what the difference it.

The full study was too big of a file to post. Sorry!
 
Jin

Jin

MuscleHead
Jun 15, 2018
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This reads like an advert for the whey protein industry.

And it’s counter to almost all I’ve ever heard about protein timing (48 hour anabolic window post training)

Further more, 18 participants?

No offense at all to OP. But I’d rather trust Mr. Nippard and MrRippedZilla than Dr. Kim and Dr. Park.
 
CFM

CFM

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Mar 18, 2012
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While you might think that whey protein is a rather recent invention, the first time whey was “discovered” dates back some 8000 years when the art of cheesemaking was first developed. I was 22 years old.
 
Bigtex

Bigtex

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While you might think that whey protein is a rather recent invention, the first time whey was “discovered” dates back some 8000 years when the art of cheesemaking was first developed. I was 22 years old.


Exactly! Whey is the liquid portion of milk that has separated. The solid portion is casein. Casein is strained to make cheese. My wife is of Italian descent and still makes cheese in the winter from milk using a product called rennet. This causes the milk to separate quickly. We actually dried the liquid portion and made some whey but takes a whole lot of milk to make much and it is very time consuming. Mostly the liquid when is used by farmers to feed the pigs.
 
Bigtex

Bigtex

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Did they even get statistical significance with such a small population size?

Absolutely, most studies in these areas are done with rather small samples. The sample size depends on four critical quantities: the type I and type II error rates α and β, the variability of the data σ², and the effect sized. So statistical errors rates assigned compensate for differences in sample sizes. The size of the sample effects the confidence level of the study with is directly proportional to the Z-score and and standard of deviation which I believe they set at 0.5 for a +/- SD of 95% CI. Most of these studies get advice or include experts in statistics when they plan the study. I am far from an expert on statistics but all of this stuff is covered under METHODS/RESULTS.

Remember also, in research, sooner or later someone one else will duplicate the study to see if they get the same data. They may add more subjects or even lengthen the time. But for the most part sample size is determined by any previous research in the area. There have been other studies done in this area with similar sample sizes but this particular study used trained subject which increases the validity as far as sports is concerned.

Like I said, I think it would be interesting to do the same study and have the PLA group, the PRO group and a 3rd group that was consuming a very high protein diet + supplementing with when before and after training. I know the importance of high protein in diets because of the THF (thermic effect of food) but as far as hypertrophy are amino acids needs the most important around training? Therefore protein could be cycled kind of like carbohydrates.
 
DungeonDweller

DungeonDweller

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Mar 21, 2017
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I mean, I like the results, and I didn't look up the results to look at the statistically analysis since its been nearly a decade since I took any sort of stats class so I'm not an expert on it. Its just that with 18 samples and some of them were on a placebo... I hope someone takes this further.
 
Bigtex

Bigtex

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Aug 14, 2012
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Many of these studies done in the areas of nutrition and exercise science are not very well funded. Understandably, there is just not that much interest in either of these two areas in the big scientific world. So the larger the sample the bigger the budget needs to be. I am just happy to see that science is finally starting to invest why athletes do what they do and get the results they get. This particular study was sponsored by a research fund from the Korean Ministry of Education.

Richard Kreider is one of the researchers in this study. He has been doing research in both areas for over 30 years and is very well respected. He works at Texas A&M where he is the Executive Director of the Human Clinical Research Facility (HCRF),and Director of the Exercise & Sport Nutrition Lab at Texas A&M University. He would not attach his name to a study that was on shaky grounds,

It has been about 25 years since I took any stats but I have participated in several research studies and have had to input data and run stats analysis software. I understand it but the stats geeks pretty much tell you what to use and how to read it.

Oh, the study actually started with 24 subjects, Six of them dropped out at some point due to different reasons.
 
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searay

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Dec 20, 2017
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you would think there would be more interest in the medical community to help recover faster from injuries using bcaa during physical therapy and whey after to recover faster. also, I and several gym friends who use bcaa during there workouts notice an increase in energy towards the end of the workout so we can train harder during the entire workout and then take whey post wkout and a big meal 1 hr later. why not cover all the bases?
 
Bigtex

Bigtex

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Aug 14, 2012
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I talked to our statistics department to day to help me clear this stats stuff up in my head so I could offer a much better explanation. So, let me explain, hopefully a little more clearly about determining the sample size and the validity of small samples. Of course, the larger the sample the lower the margin of error and the higher the confidence level as well as the lower the standard deviation. However, with statistics this can all be calculated to fit your particular study based on the goal of your study. Larger samples are important when you are comparing the results to a larger group. Politics is a good example. When you poll, you are using your sample as a representative of the entire population. Confidence levels need to be high (95-98%) and margin of error needs to be very low. Even in political polls with a large sample they commonly use a margin of error of +/-3%.

To design a study with the sample size we have we need to determine the confidence level (CI). This simply means how confident do you want to be that the actual mean falls within your confidence interval? The most common confidence intervals used in research are 90% confident, 95% confident, and 99% confident. The present study used 95% CI. Confidence levels then correspond to a z score which will be used in a statistical formula to determine sample size and minimums.

  • 90% – Z Score = 1.645
  • 95% – Z Score = 1.96
  • 99% – Z Score = 2.576
Next we need to determine the margin of error. Understanding that no sample will be perfect, we must decide how much error we are willing to allow. The margin of error determines how much higher or lower than the population mean you are willing to let your sample mean fall. If you’ve ever seen a political poll on the news, you’ve seen a margin of error. For example, it will look something like this: “93% of voters said yes to Candidate A, with a margin of error of +/- 5%.” 5% is usually most accepted margin of error. This study chose to use a margin of error of +/-5%.

So let’s say we are doing a political poll and have gotten together a sample of 1000 subjects to test. We want this to be very accurate and we set the confidence level to 99%. Our margin of error will be 1%. This leaves very little room for error. So out of that 1000 subjects the minimum we can end up with is 944 subjects and still very very accurate. If we go to a CI of 95% and 0.5% we need at least 278 subject while still being pretty damn accurate.

So to this study,,,if we increase the confidence level to 99% and 1% we need 28 subjects to reach that level of confidence. We can't afford to loose one subject or get bad data of the confidence level will change. So, smaller samples in this type of study are not so important because you are not comparing the small sample to the entire population of America rather comparing one group to another, both of the same size.

If we drop it to 95% and 5% which is most common, 27 subjects are needed. If we drop to 18 subjects, you need to end up with good data for all the subjects or the CI will have to be lowered from 95% to 90% and the margin of error increased.

Hope this helped those of us like myself who are mathematical retards to understand this better. Yeah, I had to take college algebra two times to pass with a C.
 
D

davgtr93

Member
Mar 9, 2021
18
6
I read this article in 2019 and am rereading it now. I agree with the conclusion. It would also be interesting to read about the difference between vegan and regular protein. Because there is a difference in price, but I don't see a difference in quality.
 
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