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All athletes desire to excel. In this pursuit of excellence, athletes look for ways to
enhance their training and performance. Today there exists a plethora of training routines
and exercises, nutritional programs, dietary supplements, and, consisting of the most
diversity, viewpoints as to the optimal way to achieve this hunger for victory. This makes
sifting through all the available options a difficult and often times frustrating task.
Time and time again though, examining scientific journals instead of the latest muscle
magazine proves to produce the best results? Why? Because the information presented in
these scientific studies is based on actual data and observations and not from the local
gym guru. In this article, we will examine a scientifically backed nutrition and
supplement plan designed to promote an anabolic environment that will ensure growth
and advancement.
Protein Turnover
Before we discuss the dietary blueprint for anabolism, an understanding of how muscle
grows and gets stronger must be gained. All tissue of the body (skin, hair, muscle, etc.)
goes through a process of turnover, or renewal. With skin, old tissue dies off and is
replaced with new skin. This renewal process is accelerated if the tissue experiences a
form of stimulus or overload. Concerning skin, a guitar player's fingers serve as a fine
example.
When some people first begin to play the guitar, the tips of their fingers are soft. This
makes playing against steel strings painful. Frequent playing causes the skin at the tips of
the fingers, where they come in contact with the guitar strings, to become hard and
calloused. The old, soft skin has been replaced by a tough, durable layer of skin, allowing
the guitar player to play with ease and comfort. Without turnover taking place, new skin
would not have formed. The same process applies to muscle tissue.
Muscle tissue, just like skin, is constantly being turned over. The rate at which this turn
over occurs is governed by protein synthesis and protein breakdown. In turn, protein
synthesis and protein breakdown are regulated by ones diet, lifestyle (sedentary verses
active), and genetics [2]. Just as the guitar player must apply a stimulus (the steel strings),
an athlete must stimulate their muscles with exercise to accelerate this process.
The purpose of exercise, especially resistance training, is to increase this protein
turnover. This includes both protein synthesis and breakdown. When a weight lifting
exercise is performed, the muscle cells used to create the force needed to achieve the
desired movement can become damaged. By progressively increasing the weight lifted
and the force needed to move the weight, the body becomes programmed to think it must
prepare itself for heavier workloads. Therefore the damaged muscle cells are removed
and replaced with new, stronger muscle. This process continues while the exercise bouts
continue. When the exercise bouts cease, so will the process of replacing the old, weaker
muscle with new, stronger muscle.
Going back to the guitar player example, when a guitar player stops playing the guitar for
a period of time, the callouses that were formed fade away. The body senses there is no
longer a need for the tough layer of skin and replaces it with weaker skin. The exact thing
happens with muscle tissue. That is why when one stops lifting weights, their muscle stop
growing and actually decreases in size and strength. This is just a brief overview of
protein turnover. For the purpose of this article, we do not need to get into transcription
and translation.
It should be clear that in order to continuously prep the body to create new, stronger
muscle, one must overload the muscle. But what happens when overload occurs and there
are not adequate materials to create the new muscle? Muscle is lost!
Protein Turnover = Protein Synthesis - Protein Breakdown
If the amount of muscle broken down exceeds the amount that can be replaced, protein
turnover is negative and there is a net loss of muscle. This is counterproductive to what
the athlete is trying to accomplish with training. To ensure that an athlete's hard work and
time spent exercising is not wasted, protein turnover must remain positive. To accomplish
this, precise nutritional requirements must be meet.
Protein
The word protein comes from the Greek word meaning "of prime importance." The
naming of this nitrogen-containing macronutrient is extremely fitting, especially when
considering its need during strenuous periods, such as exercise. Proteins are the most
abundant organic compounds in the body [15]. The primary function of protein is growth
and repair of body tissue (anabolism). Proteins can also be used as energy through
catabolic reactions, such as gluconeogenesis. Amino acids are the "building blocks" of
protein. Amino acids are made up of an amino radical (NH2) and a carboxyl group
(COOH). What make amino acids different are their side chains.
A protein molecule is made up of long chains of amino acids bonded to each other by
amide bonds, or peptide linkages. An almost endless combination of amino acid bonds
can exist. The combination of amino acids governs the protein's properties.
Amino acids can be divided into many groups based on their physical properties. For the
purposes of our discussion there are two that are relevant: essential amino acids (EAA)
and nonessential amino acids (NEAA). EAA must be consumed through ones diet,
because they cannot be synthesized in the body at a sufficient rate to meet demands [15].
NEAA can be synthesized in the body from other protein and non-protein nutrients.
Essential Amino Acids Nonessential Amino Acids
Histidine
Alanine
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Tryptophan
Valine
Arginine
Aspartic Acid
Cysteine
Cystine
Glutamic Acid
Glutamine
Glycine
Proline
Serine
Tyrosine
Amino acids have a very strong impact on muscle growth. Specific amino acids and
amino acid combinations also have special properties. Combinations of different
carbohydrates also create special properties.
What Happens During A Workout?
I'd like to note that my reference to exercise will be dealing with strength training and not
endurance training. The effects of endurance training on protein turnover are somewhat
different than the effects from strength training.
After completing an exercise session, two main things have occurred. One is the
depletion of muscle glycogen. And the other is an increase in protein breakdown [25].
Protein synthesis has decreased [9], experienced no change [10] from its pre-workout status,
or slightly increased [4]. Remember when one lifts weights, muscle cells are damaged.
When these cells are damaged, they are removed. Because of the elevated level of protein
breakdown and the almost unchanged level of protein synthesis, protein turnover is
negative, meaning one is in a catabolic state [13].
Protein Breakdown
During exercise, catabolic activities cause proteins and muscle tissue to be broken down.
The greater the intensity of the workout, the greater the catabolic response. This is due to
the increase in production of catecholamines and glucocorticoids. Of prime concern to us
is the glucocorticoid cortisol.
Cortisol is a very catabolic hormone as it increases muscle protein breakdown [11, 25].
Cortisol regulates glucose synthesis from amino acids through the process of
gluconeogenesis [15]. Cortisol has been shown to increase protein breakdown by 5-20%[7]!
Another reason why exercising with low glycogen levels is a bad idea is lean muscle
tissue will be lost. This loss in muscle is due to the intracellular pool of amino acids being
depleted. In order to maintain this pool, muscle tissue most be broken down [30].
Cortisol also negatively affects certain hormones. Cortisol can inhibit growth hormone
levels by activating the release of somatostatin, an antagonist of growth hormone. It has
also been shown to reduce IGF-1 expression. IGF-1 is one of the most anabolic hormones
in the body. Any decrease is unwanted. Cortisol also inhibits thyroid-stimulating
hormone (TSH) [11]. This can cause a decrease in ones metabolic rate, making it harder to
lose body fat. In order to recover adequately from exercise, cortisol levels must be
controlled.
Anabolic Nutrition
Recovery Goals
From the above, it should be obvious that during training we need to:


Reduce muscle protein breakdown
Significantly increase protein synthesis
How can this be done? By using a scientifically backed nutrition plan. Studies have
shown that in the absence of food, protein breakdown exceeded protein synthesis after a
workout [4, 19, 20]. Most athletes know the positive effects of consuming a post workout
meal. The body is primed for nutrient uptake after a workout. One way, and the most
popular way, to accomplish the above is to consume a “workout shake”.
Amino Acids & Exercise
Only six of the 20 amino acids are directly metabolized by muscle. These six amino acids
are: alanine, aspartate, glutamine, isoleucine, leucine, and valine[14, 36] These six amino
acids are metabolized at accelerated rates during exercise [36] They are also imtermediates
that regenerate the aerobic-TCA energy cycle [36] During exercise, the carbon atoms from
these amino acids are unbidden by protein degradation. The Brain Chain Amino Acids
(BCAA) and glutamine are then used to synthesize intermediates for use in the TCA
cycle.
This is not good for muscle anabolism because the cellular levels of these amino acids
greatly impact growth. Therefore when the supply is depleted, growth significantly
suffers. Of these six amino acids, alanine, aspartate, and glutamine are nonessential, but
isoleucine, leucine, and valine are the essential branch chain amino acids (BCAA), which
serve an even greater role in energy metabolism and muscle growth.
BCAA are of extreme importance. BCAAs are absorbed directly into the circulatory
system, bypassing the liver, which allows them to be used for rapid protein synthesis.
Studies have shown that BCAA directly supply the nitrogen needed to create and export
concentrations of alanine and glutamine produced by muscle [14, 21, 34, 35]. Because of this,
BCAA concentrations are lowered from any type of exercise. One study showed that
BCAA concentrations were decreased by 30% from aerobic exericise and 8-20% from
anaerobic/aerobic exercise [21]. The largest decrease in BCAA concentrations were seen
in anaerobic exercise, such as weight training [22]. Of the three BCAA, leucine is of
greatest importance during exercise.
Transaminiation of leucine's nitrogen to alanine is doubled during exercise [36]. Leucine is
the only amino acid that is capable of being completely oxidized in the TCA-aerobic
cycle. Because leucine is an EAA, this oxidation capability is not good for muscle
growth, as it can quickly deplete leucine levels. Leucine has been shown to directly
stimulate protein synthesis and muscle turnover [28, 33], and without leucine, protein
synthesis rates are impaired [8]. To make matters worse, leucine has the shortest half-life
of all amino acids in the free pool of 45 minutes. This is compared to the 5-10 hour half
lives of the other amino acids [21]. It is constantly being oxidized, leaving little for protein
synthesis. Leucine levels need to be increased before protein synthesis can excel.
It should be obvious from examining the above information that the protein source used
must contain large amounts of EAA, especially BCAA, and with even more emphasis on
leucine. Mero showed that consuming a BCAA supplement, with 30-35% leucine, before
or during exercise decreased the rate of protein breakdown, improved both mental and
physical performance, and had a sparing effect on muscle glycogen levels [21].
To meet the need for amino acids during exercise, a supplement containing high amounts
of EAA and especially BCAA is needed. In order for this protein to be as effective as
possible, it needs be a fast absorbing protein. Therefore, protein powders such as casein
and milk isolate are discouraged because of their slow digestion rates. Egg protein is
another option, but it is still absorbed too slow. These slow digesting protein can create
an environment in the intestines that competes with the muscles for blood flow.
Though this competition for blood is not substantially strong it still exists. That leaves us
with whey protein. The quickest absorbed of the whey family is hydrolyzed whey.
Hydrolyzed whey is one of the most rapidly digested proteins available.
Hydrolyzed whey has an excellent amino acid profile. Here is the amino acid profile of
25 grams of a typical (some will vary) hydrolyzed whey protein powder:
Amino Acid Name Amino Acid Profile
Alanine
1115
Arginine
407.5
Aspartic Acid
2550
Cystine
525
Glutamic Acid
4095
Glycine
367.5
Histidine
363.75
Isoleucine
1562.5
Leucine
2236.25
Lysine
Methionine
Phenylalanine
Proline
Serine
Threonine
Tryptophan
Tyrosine
Valine
2268.75
440
491.25
1363
1027.5
1727.5
337.5
1435
1326.25
Total Amio Acids: 23639.25 mg (23.63925 grams)
10753.75 mg (10.75375 grams)~ 45.5%
Total EAA:
12885.5 mg (12.8855 grams)~ 54.5%
Total NEAA:
5125 mg (5.125 grams)~ 21.7%
Total BCAA:
As you can see, hydrolyzed whey protein is close to 50% EAA and 50% NEAA. In order
to get the amount of EAA and BCAA that we need to ensure growth, a large serving of
this whey needs to be consumed.
NEAA Are Not Needed
Research studies have shown time and time again that NEAA are not needed to stimulate
protein synthesis when EAA are consumed [6, 27, 32]. A study showed that consuming
NEAA did not increase protein synthesis while consuming EAA did in fact increase
protein synthesis [32]. A single six-gram serving of EAA is more than twice as effective as
two, six-gram servings of mixed amino acids (EAA and NEAA) in increasing protein
synthesis [1, 32]. A 200% increase in protein synthesis was observed due to EAA available
after resistance exercise [4].
It has been shown that exercising after ingestion of an EAA drink maintained
intracellular levels of NEAA. This showed that NEAA availability did not limit protein
synthesis. The intracellular pool of amino acids were increased with EAA
supplementation, but not with supplementation of EAA + NEAA [6], meaning when EAA
are consumed, they go into the cells. This is in part due to EAA absorption speed.
EAA are the fastest absorbed of all amino acids [24]. All these facts show that half of the
amino acids we consume from the whey protein are needed for increased anabolic
activity. All these benefits were seen just with the ingestion of 6 grams of EAA. All of
this happens irrelevant of carbohydrate consumption, but when combined with the proper
fuel source, you are able to train at even higher levels without risking the loss of the
precious EAA.
Pre-Workout Better Than Post Workout?
Tipton et al [29] found that consuming amino acids before exercise resulting in greater
delivery of these amino acids than when consumed after exercise.
This greater delivery is due to increased blood flow to the working muscles. At rest,
about five liters of blood are being circulated per minute, with only 15-20% going to
skeletal muscle. During exercise, blood flow is increased to 20-25 liters per minute, with
80-85% of the blood going to skeletal muscle. This occurs through autoregulation.
Autoregulation causes the smooth muscles surrounding the arteries to contract, which
causes the arterioles to constrict. This decreases blood flow to organs that do not need it.
When the muscles become active, they need the blood the most, so it is sent to them [26].
Due to this increased blood flow, by consuming EAA before and after your workout,
there was an increase in protein synthesis for the rest of the day [31]! Consuming a shake
pre-workout will not decrease the effectiveness of a post workout shake or retard the
elevation in lipid oxidation after a workout, but rather enhance them.
In order to isolate the EAA, and receive the greatest benefit from them, they must be
consumed in free form. Free form amino acids do not need to be digested. This means
that they bypass the liver. The liver is the "gate keeper" of the body. It decides what
nutrients get sent into the peripheral circulation and what nutrients get broken down and
secreted or stored. When amino acids are consumed, their peptide bonds must be broken
in order to be digested. When glycogen levels are low, many of the amino acids
consumed end up as glucose and never make it to the peripheral blood circulation, which
means they never make it to the muscle! By using free form EAA, we bypass the liver,
sending the amino acids straight into the peripheral circulation. This also diminishes the
need to direct blood away from the muscle to the intestines to aid in digestion. Most
importantly, we increase protein synthesis!
*Note: Due to FDA regulations and its sedentary effects, the EEA tryptophan should not
be included in your EAA mix.
Introducing Primaforce Primal EAA
Primaforce Primal EAA is a scientific bled of Essential Amino Acids (EAA)
containing a heavy dose of the amino acid L-Leucine. L-Leucine is touted in the
scientific community as the “anabolic-trigger” of all the amino acids. Primal EAA is
specifically formulated for “Workout Nutrition” to provide the ammo your body
needs to promote lean mass gains and prevent catabolism (muscle loss).
The reason for consuming the high amounts of leucine is as
follows:
Stimulation Of Insulin Secretion, PI3K, & Protein Synthesis By Leucine
One pathway through which protein synthesis can be increased is the
phosphatodyl-inositol-3-kinase pathway (PI3K). PI3K regulates glucose uptake through
GLUT4 translocation and also increases amino acid uptake. Insulin, the body's "storage"
hormone, works by activating the PI3K pathway.
Interestingly, leucine ingestion causes insulin secretion, but leucine can also
directly activate PI3K in the absence insulin [23] , suggesting leucine to have a
synergistic role with insulin as a PI3K activator [16]. So not only can leucine increase
glucose uptake, it can also increase its own and other amino acids' uptake into cells.
These facts suggest that taking additional BCAA with carbohydrates around ones
workout will lead to a synergistic increase in glucose and amino acid uptake into skeletal
muscle. Leucine can stimulate protein synthesis through insulin secretion and the
activation of the PI3K pathway, but can also stimulate protein synthesis through other
pathways.
Activation Of mTOR By Leucine
The Mammalian Target of Rapamycin (mTOR) is one of the body's protein
synthesis regulators. MTOR functions as an energy sensor; it is activated when ATP
levels are high and blocked when ATP levels are decreased (AMPK is activated when
ATP decreases, which works antagonistically to mTOR).
The main energy-consuming process in the cell is protein synthesis. When mTOR
is activated (high ATP levels sensed) protein synthesis is increased and when mTOR is
suppressed (low ATP levels are sensed) protein synthesis is blunted. MTOR activation is
vital for skeletal muscle hypertrophy.
Interestingly, mTOR is also a nutrient sensor of amino acid availability,
specifically of leucine availability. Research has shown that regulation of mTOR by ATP
and amino acids act independently through separate mechanisms [12].
Leucine is the key regulator of the mTOR-signaling pathway [2, 18]. According
to Laymen , "The increase in leucine concentration is sensed by an element of the insulinsignaling pathway and triggers a phosphorylation cascade that stimulates the translational
initiation factors eIF4 and p70S6K."[17](See figure 2)
Activation of these initiation factors initiates the translation of muscle mRNA
components and are vital for skeletal muscle protein synthesis and creation of new
contractile proteins (muscle). Leucine directly signals and primes your muscles to grow
through the activation of mTOR.
Click To Enlarge.
Insulin signaling cascade [adapted from Laymen (17) amd Anthony et at. (39)]. IRS1, Insulin receptor substrate 1; Pß-K, phosphatidylinostitol-3 kinase; GLUT4,
Insulin-dependent glucose transporter; PKC, proteinkinase C; mTOR, mammial
target of rapamycin; el F4, translational factor 4.
Figure 3 - Adapted from: Layman, DK (2003)[17]. The role of leucine in weight loss
diets and glucose homeostasis. J. Nutr. 133: 261S-267S.
We see that leucine stimulates protein synthesis through both insulin
secretion/activation of PI3K pathway and activation of the mTOR pathway, but there is
still a third pathway through which leucine stimulates protein synthesis; a mTORindependent pathway that not much is known about (and hence will not be discussed in
this article). Sign up for article updates here.
Stimulation of Leptin Expression through mTOR activation in Adipocytes
Intake of leucine stimulates expression of the hormone leptin in adipocytes (the
primary site of leptin secretion) through activation of the mTOR pathway (Meijer and
Dubbelhuis, 2003). Leptin is a very complicated hormone; the gist of it is involved in the
regulation of metabolism, body weight, and appetite.
Leptin secretion is linked with body fat levels; higher body fat is associated with
higher leptin secretion and lower body fat is associated with lower leptin levels. When
you diet and lose fat, the amount of leptin you secrete decreases, which makes your body
"crave" food in an attempt to bring your body fat level back up to where the body is
comfortable (known as the body fat "set point").
Leucine has the ability to activate leptin expression and will cause the body to
think it is "fed" or receiving "adequate" calories, which will keep things running
(specifically your metabolism) smoothly.
Cost vs. Benefit
When it comes down to it, everyone is concerned with the cost of their supplements.
Some are willing to pay a little extra for quality supplements, while others are not.
Initially, people look at this setup and think it is not cost effective or they can get the
same benefits by just taking whey protein. While whey protein is good, it should be clear
that consuming free form EAA, especially leucine, have many more advantages. Some
also say that they can just increase the amount of whey protein they take to get more of
the EAA and BCAA. By doing this, you are now spending more money, which was your
primary concern. In the end, one will get the most "bang for their buck" from this setup.
Unlike other plans, this setup increases anabolism while decreasing catabolism. If
performing at your full potential is important to you, then you will use what has been
shown to work best. Why pay for something that will not deliver the best results?
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