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What are the reasons I should supplement with whey protein?

  • To build muscle mass
  • To speed recovery time
  • Reduce injuries related to working out
  • Maintain a healthy and fit body
  • Feel better during your workouts


Are there any independent controlled studies that prove at statistically significant that taking whey protein as a supplement will cause you to gain muscle mass?

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3 Answers 3

By itself? No. When paired with a workout regime? Yes.

The purpose of Whey Protein (or indeed, any complete protein source) as a supplement is to be utilized in lean-tissue anabolism (growth). In order for muscle mass to increase, there must be three things present:

1) Significant stress on the muscles, either increased weight or increased length of activity.

2) Protein to build the new cellular structures.

3) An excess Caloric intake (lest your body simply deconstruct the new muscle for energy instead of retaining it).

Whey Powder, or other sources of complete protein supplements, addresses #2. While Protein supplements do contain Calories, unless the workout is short, you will burn more energy than the supplement contains.

A Placebo-controlled study has shown the following:

Results showed that protein supplementation during resistance training, independent of source, increased lean tissue mass and strength over isocaloric placebo and resistance training (P < 0.05).

However, how much additional protein is necessary can be difficult to determine, as this study in the Journal of Applied Physiology takes the time to research:

The [High-Protein] diet did not result in increased [Whole Body Protein Synthesis] compared with the [Moderate-Protein] diet, but leucine oxidation did increase significantly, indicating a nutrient overload... In summary, protein requirements for athletes performing strength training are greater than for sedentary individuals and are above current Canadian and US recommended daily protein intake requirements for young healthy males.

Although there are two caveats to the above study. It was done over 13-days, so long-term side-effects (or lack thereof) weren't displayed, and the High-Protein diet consisted of 2.4g of protein per kg of body-weight per day, which is very high (3x the USDA recommended daily intake).

The Moderate-Protein diet in the study above (1.4g/protein per kg body-weight per day) is actually much closer to the recommendations of popular strength-training websites.

Whey Protein, by itself, will not make you gain muscle mass. In a workout program designed to build lean muscle mass, Protein Supplements can help you achieve your goals faster.

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It's also worth mentioning that most Americans already eat a high protein diet. For me (160 lbs/73 kg), 1.4 g/kg (the moderate-protein diet in the second study) comes out to ~100 g protein per day, which is the average for US males. –  Brendan Long Dec 10 '12 at 16:25
Nothing special about supplementation compared to just eating a high-protein diet? –  Kate Jan 5 '14 at 1:35
@Kate - Not really. The body will hold onto the protein until it's needed throughout the day, so unless you're training for Strong Man the fine differences between eating a piece of chicken four hours before and having a whey protein shake 20 minutes after is negligible. –  MCM Jan 5 '14 at 2:09

Just whey protein consumption by itself won't make you gain muscle. As far as whey is concerned it is a fast moving protein so if the body doesn't have any place to store the incoming whey it is simply burned off for energy. Here's the resource for this info.

Muscles growth is based on two factors:

  1. Necessity for the muscle tissue to grow.
  2. Adequate nutrition that can help it to grow.

So if you engage in adequate exercise that force your muscles to increase so as to handle the stress of exercise then taking some amount of whey (or better, some slow moving protein) post exercise would help in muscle recovery and growth.

W.r.t. the second part of your question, the same site also cites a Boirie study from 1997 which compares the effects of Whey VS Casein on muscle growth in athletes. You might find your answer there.

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The first reference is non-peer-reviewed - unfortunately, nutrition is an areas where a lot of nonsense rumours are shared, making it hard to trust anyone with some science behind it. For the second link, perhaps you could extract an answer to the question (with some cites)? Otherwise, it isn't an answer, it is just a pointer. –  Oddthinking Oct 14 '11 at 5:13

This is not an exact answer to your question, but, the information gives the place of whey protein in a body-builders diet.

Even the manufacturers will never claim it helps you gain muscle mass just like that. You have to workout.

When you workout, you essentially micro-tear your muscle, so, while you are resting the muscles are rebuilt and this process leaves more muscle than you began with.

Creation of muscle needs proteins, if you're into heavy body building -- You can get these in your diet by eggs and other things + you need to use protein supplements to fill the remaining gap.

In my opinion form my experience, taking just whey protein shakes will not do anything, unless you workout.

How big you get is controlled by your genes, hormones, diet & workout plan. I think it has its place in the diet of people that need large amounts of proteins and it makes sense to take these.

I am however not aware of any specific scientific studies. I'm pretty sure quite a few on this must be out there, these products are approved by the FDA, so I don't think they are released without test.

Interesting video :
This is what I use, very good product :

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Thanks for the answer, I am skeptical that even with workouts whey protein will help you make gains above an identical diet sans the whey. –  GBa Apr 30 '11 at 13:21
I think if you take an equal amount of protein in your diet, its will be the same. But after you reach a level, this is just so much easier. I know guys that eat 2 and 3 dozens of eggs at a time. I'd prefer the shake to it any day. –  DMin Apr 30 '11 at 13:32
If you have to begin an answer with, "this is not an [...] answer to your question", you're already off to a bad start. Explain why you can't/won't answer, why the question is flawed, how the source has been misinterpreted, etc. And also, don't bother relaying personal experience or opinion - they have little value here. –  Shog9 Apr 30 '11 at 16:27
my next question is going to be about "are there any controlled experiments that show that water actually hydrates my body.." --- relax a little -- BTW, a Shocking discovery! "Most normal people use their personal experience to infer the truth."[citation needed] -- Bloody blasphemous idiots, how dare they... –  DMin May 1 '11 at 4:24
"Most normal people" also consistently draw incorrect conclusions. Welcome to Skeptics.SE, where the standards are refreshingly higher. Please provide some references (preferably peer-reviewed) to support your claims. –  Oddthinking Oct 14 '11 at 5:16

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