Answered: Your Most Burning Questions about Building Muscle/Strength With Protein
[Part 2: What To Use]

This is Part 2 of a 3-part series on building muscle and strength with protein.  Before reading, you might want to check out the Introduction and Part 1 of the series.

[Part 2] What To Use

You'll recall that in the last post I addressed how much protein a strength athlete should take in every day, even giving specific guidelines based on diet strategy, body composition, etc.

In this article, I'm going to address the question I posed at the end of the last one in this series: specifically what protein should you use as your day-to-day core or foundational protein?  Remember that this is to supplement your whole food protein intake and ensure you're consuming enough to maximize muscle growth and strength.

Let's start by reviewing various protein powder types and their relative merits for strength athletes.  (I'm ignoring whole foods [e.g. animal and vegetable sources] because our interest is in the best proteins to supplement your whole-food diet.)

Whey 

• Whey is a complete protein (i.e. contains all the essential amino acids) with an excellent amino acid profile for athletes.  It contains a high concentration of branched chain amino acids (BCAAs) that are important for their role in protein synthesis, as well as for the maintenance of tissue and prevention of catabolic actions during resistance training.  (Remember from the last post that reducing protein catabolism can itself lead to muscle growth.)
• Whey contains biologically active components that provide additional benefits to enhance function and athletic performance. For example, it contains an ample supply of the amino acid cysteine, which is believed to increase glutathione levels.  Glutathione has been shown to have powerful antioxidant properties that can aid the body in fighting various diseases [Counous, 2000].  (Staying healthy enables an athlete to consistently train hard, in addition to providing a metabolic environment primed for enhancements in muscle size and strength.)
• Whey consists of a number of other proteins that improve immune function through antimicrobial activity [Ha et al. 2003].

Casein

Casein is the major protein component of cow's milk, accounting for nearly 70-80% of its total protein (whey constitutes the other 20-30%), and gives milk its characteristic white color.

Casein is also an excellent quality protein for strength athletes.  Its benefits for athletic performance are summarized below:

• Casein, like whey, consists of an impressive amino acid profile. Although not as rich in BCAAs as whey, it still contains a hefty dose, particularly of the BCAA leucine (which triggers protein synthesis). Casein is approx. 8% leucine, while whey is roughly 10%.
• Casein exists in milk in the form of a micelle.  A major benefit of the casein micelle is its ability to form a gel or clot in the stomach, which makes it very efficient in nutrient supply. The clot provides a sustained, slow release of amino acids into the blood stream, often lasting for several hours [Boirie et al. 1997].  Of particular importance to weight training athletes, this slow and steady supply of amino acids provides better nitrogen retention and utilization by the body, and accounts for casein's notorious (and unique) anti-catabolic properties.  (Note that casein, like whey, exists in various forms in commercial applications. The best and purest form is micellar casein, which is characterized by the preservation of the casein micelles described above.  Remember that it's the micelle form that gives casein its critical anti-catabolic action by slowing protein metabolism.)
• Casein is important to the body for functions relating to the uptake of nutrients and vitamins, and is are a source of biologically active peptides.

Soy

Soy protein is derived from the soybean, and is the most widely available vegetable protein.

Soy isn't currently a popular protein among strength athletes (which I'll address below), but does contain a number of health benefits, including:

• It is a complete protein with a high concentration of BCAA’s.
• Potentially reduces plasma lipid profiles, increases LDL-cholesterol oxidation and reduced blood pressure, although these claims are considered inconclusive.

Why isn't this such an attractive protein for athletes?

Well, soy contains certain isoflavones that are considered phytoestrogens (i.e. plant-derived compounds that exhibit estrogen-like effects).  It is for this reason that many women who are at higher risk for breast cancer (due to familial incidence and such) are often instructed by their doctors to avoid soy-containing foods, for the estrogenic action of soy can increase the cancer risks.

It goes without saying that for athletes interested in lean muscle and strength, avoiding supplements with potential estrogenic properties is a wise decision in support of healthy testosterone production and an overall anabolic environment.

Egg

The most common form of egg protein found in commercial products today is egg albumen, which is essentially egg white protein.  The powder is made by isolating the egg white, pulverizing it and then drying the remains. Sounds delicious, right?  :)

Egg albumen is a high-quality protein source for athletes, the benefits of which include:

• It is a complete protein with a high concentration of BCAAs (it is about 9% leucine by weight, which falls halfway between whey and casein).
• Egg is relatively quickly absorbed (though not as rapidly as whey protein), making it a decent post-workout protein for jump-starting protein synthesis.

Before The Conclusion, A Word On Protein Effectiveness

OK, so after reviewing the benefits of various protein types, one question remains: what's the most effective for building muscle and strength?

Well, protein effectiveness is a function of 2 things:

1. Quality
2. Digestibility

The first, quality, refers to the availability of amino acids that it supplies, while the second, digestibility, considers how the protein is best utilized.

Thus, the protein type (or types) that will be most effective for strength athletes (as a meal replacement or supplement between meals) is that which efficiently and sustainably delivers an amino acid profile high in BCAAs, supplying the building blocks (and triggers) for protein synthesis rapidly, and then steadily over a period of hours.

The Bottom Line -- Use a Whey/Casein Blend For Your Protein Foundation

Combining high-quality whey and casein proteins (preferably WPI and micellar casein) produces the most potent complex of proteins for maximizing protein synthesis and minimizing protein degradation (catabolism).

Why not soy or egg albumen?

Well, soy has the problem of being potentially estrogenic, which strength training athletes should avoid because it can interfere with healthy testosterone levels.  So that's OUT.

With respect to egg albumen... It's simply unnecessary.  

Yes, it's high in BCAAs (higher than casein), but digests at a rate somewhere between whey and casein (closer to whey than casein), so a good quality whey (which is higher in BCAAs and delivers them faster) is a better choice, hands down.

The reason I strongly recommend combining casein with whey rather than egg is because micellar casein is the slower digesting option, and the only protein to have been shown in research studies to exert an anti-catabolic effect.  Thus, with whey and casein (as opposed to any other combination), you get the best of both worlds: the best protein for kick-starting muscle growth (whey) and the best protein for nitrogen retention and protein sparing (casein).

This is truly an ideal (perhaps synergistic) combination. T

here Are A Lot Of Whey/Casein Blends On the Market...  This Is What To Look For When Choosing One

Stay tuned for the 3rd and final post in this blog series, for in it I will answer the question of what you should look for in a protein blend.  

The market is flooded with seemingly homogeneous products, many purporting to somehow be better than the next without delivering anything truly exceptional. I will provide clarity.

Until next time,

Todd