Primaforce Primal EAA

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 The old, soft skin has been replaced by a tough, durable layer of skin, allowing the guitar player to play with ease and comfort.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.

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:

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 insulin-signaling 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.

Insulin signaling cascade [adapted from Laymen (17) amd Anthony et at. (39)]. IRS-1, 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 mTOR-independent 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?

Servings Per Container: 60

Serving Size: 1 Scoop (18.18 Grams)

L-Leucine 4860mg

L-Valine 2160mg

L-Lysine HCL 2160mg

L-Phenylalanine 1836mg

L-Threonine 1296mg

L-Isoleucine 864mg

L-Histidine 702mg

L-Methionine 486mg  

Other Ingredients: Natural & Artificial Flavors, Citric Acid, Acesulfame Potassium, Sucralose, Yellow #

References

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