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PROTEIN The sine qua non of Muscle-Building

Posted by VPX Sports on Feb 19, 2010 4:47:00 PM

The sine qua non of Muscle-Building

Proteins, from the Greek word meaning "of prime importance," are definitely an important component of bodybuilders eating program. Just as glucose serves as the building block of glycogen, so are amino acids, which are the building blocks of proteins. Proteins are arguably the most important component of your cells. They're involved in formation of contractile tissue or muscle, they make up a large part of the structural component of cells, they are a part of enzymes, antibodies, blood, etc...you name it, protein is part of it.

Even though the primary function of protein is to provide the needed amino acids for maintaining an anabolic state, there are times when it may actually be used as a fuel source. This usually occurs when you're in a carbohydrate-depleted state (ex. on a low carb diet, exercising continuously for >2 hours). However, what most bodybuilders want is to maintain the absolute highest levels of anabolism or muscle building as possible. The way scientists measure this through something called nitrogen balance.

Remember that one of the components of proteins is the molecule nitrogen. In fact, nitrogen makes up about 16% of protein. So when you eat protein, you're taking in among other things nitrogen. If you want to put muscle on, you want to take in more nitrogen (i.e. protein) then you are degrading. A positive nitrogen balance exists when protein intake exceeds protein degradation. The opposite of that, a negative nitrogen balance, exists when protein intake is less than protein degradation.


Talk about a topic that's controversial. In my experience, I have met many physicians and dieticians who claim that "too much protein" is harmful. Sometimes I wonder if they've inhaled one too many times. There is NO SCIENTIFIC EVIDENCE that in a normal, healthy individual, consuming 2 or even 3 times the RDA for protein is harmful; unless of course, your kidney's don't work. But then again, you'd probably be strapped to a dialysis machine rather than a Pec Deck.

Darryn Willoughby, Ph.D. is the prominent expert in the field of sports nutrition and he states that "the hazards of eating a high protein diet are exaggerated; there isn't any evidence that eating 2 grams or more of protein per kilogram of body weight every day has a harmful effect. And it doesn't stress the kidneys or dehydrate you."

Suffice it to say that the RDA of 0.8 grams per kilogram body weight per day is GROSSLY INADEQUATE for bodybuilding. Although muscle protein degradation or breakdown increases during exercise, there is a significant increase in muscle protein synthesis for at least 24 hours after either resistance or endurance exercise. If you are not getting adequate protein during this time, then it would make sense that you probably will not grow or put muscle on. Current research suggests that 1.5-2.0 grams per kilogram per day is needed for those interested in packing on some muscle. I'd say jack that up a little more. You can't go wrong eating more protein.


Basically, the protein you eat should have the entire complement of essential amino acids. The essential amino acids (i.e. you need to eat them ‘cause your body doesn't make them) include: branched-chains (valine, leucine, isoleucine), lysine, methionine, phenylalanine, threonine, and tryptophan. (Some include histidine - infants can't make it and arginine - kids can make it as well as adults). Furthermore, the body makes cysteine from methionine and tyrosine from phenylalanine; so you might say that cysteine and tyrosine are "conditionally essential." Thus, you want to eat a complete protein; one that has all of the essential amino acids. Incomplete proteins, such as from peanuts, do NOT contain all essential amino acids. So your best bet are complete sources such as milk based (i.e. whey, casein), meats, fish, etc.

Whey is better than Casein...Most of the Time

Different dietary proteins affect whole body protein anabolism and accretion and therefore, have the potential to influence results obtained from resistance training. This study looked at the effects of supplementation with two proteins, hydrolyzed whey isolate (WI) and casein (C), on strength, body composition, and plasma glutamine levels during a 10 week, supervised resistance training program. In a double-blind protocol, 13 male, recreational bodybuilders supplemented their normal diet with either WI or C (1.5 gm/kg body wt/d) for the duration of the program. What happened? The WI group achieved a significantly greater gain in lean mass than the C group and a significant drop in fat mass compared to the C group. The WI group also achieved greater improvements in strength compared to the C group in each assessment of strength. When the strength changes were expressed relative to body weight, the WI group still achieved significantly greater improvements in strength compared to the C group.(1) So in this head to head battle, whey clearly wins. But the picture gets more interesting.

Casein Protein Rocks...At Night

So does consuming protein close to bedtime actually lead to a better anabolic effect? Ever since the original paper showing that the net leucine balance over a 7 hour period after the a protein meal was more positive with casein versus whey protein, folks have suggested that consuming casein, because of its ‘slow' digesting properties is the perfect night time protein.(2) Yet as mentioned above, when you look at the only measures that matter (i.e. muscle mass and strength), whey is the winner.

Let's fast-forward to this cool study. In this one, scientists theorized that during prolonged resistance training, time-divided ingestion pattern of casein-based protein supplement is of superior efficiency in comparison with the ingestion of the same supplement immediately before each training session. This sort of puts an interesting spin on nutrient timing. In a crossover study subjects consumed the casein supplement in the morning and in the afternoon, immediately before the training session. The other supplementation scheme included 1 morning dose, whereas the second dose was ingested in the evening, 5 hours after training. One would expect that the dose taken BEFORE training would be superior; but alas, that's why they do the studies. It looks like spacing out the consumption of casein and taking it prior to bed may be a better strategy. However, what I'd suggest is to consume a fast protein (e.g. whey) pre and/or post exercise while also consuming casein before bed time. That, IMO, is the best of all strategies.
Either way, this does throw a wrench into the nutrient timing strategy in that difference proteins may in fact have applications that vary (i.e. whey may be best pre and post workout, casein at night, etc).


Again, ideally it is best to consume a supplement with protein both immediately pre and post training. This results in a greater increase in lean body mass and 1-RM strength. The changes in body composition are due in part to a greater increase in the size of type II fibers and contractile protein content. Supplement timing represents a simple but effective strategy that enhances the adaptations desired from RE-training.(3)

Bottom line: eat a small meal every 3 hours. Make sure it's a lean protein source with a fibrous veggie and a complex carb. If you don't have time for a meal, consume any of a number of excellent Protein Rush RTDs or ZI bars (see www.vpxsports.com.)

References-Boring Science Articles Basically

  1. Cribb PJ, Williams AD, Carey MF, Hayes A. The effect of whey isolate and resistance training on strength, body composition, and plasma glutamine. Int J Sport Nutr Exerc Metab 2006;16(5):494-509.
  2. Boirie Y, Dangin M, Gachon P, Vasson MP, Maubois JL, Beaufrere B. Slow and fast dietary proteins differently modulate postprandial protein accretion. Proc Natl Acad Sci U S A 1997;94(26):14930-5.
  3. Cribb PJ, Hayes A. Effects of supplement timing and resistance exercise on skeletal muscle hypertrophy. Med Sci Sports Exerc 2006;38(11):1918-25.

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