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Amino Acids: Your Best Choice For Optimum Health, Growth, Energy And Focus.

The biological keys to exercise performance and muscle synthesis

"I'm taking in enough whey protein that has the amino acids in it, and I'm eating right and taking a vitamin/mineral supplement, how important can it be to take in extra aminos? If you've avoided amino acid supplementation for the reason above, consider this: Virtually every single biological function in the human body requires amino acids and these requirements increase during higher activity levels such as exercise. In the scientific documentaries you'll hear them sometimes referred to as the "building blocks of life, and rightly so because these protein constituents are involved in the production of everything from brain neurotransmitters and cell walls, to cartilage, muscle tissue and energy. This biological reality is crucially important to bodybuilders because the higher physical and mental activity of workouts increases the need for these "building blocks. If your exercise routine seems a bit sluggish and mass gains are progressing slowly it may well be that you're not getting enough amino acids. Maintaining the right diet and taking whey protein, although necessarily important for basic muscle tissue synthesis and good health still will not supply enough aminos for optimum performance and growth. So if you're not taking them (or only taking a couple) you should consider stepping up your workout results with one of the most crucial supplement groups. The following will help you understand what they do and how to use them effectively. Before we get into the specifics of what each one does, here's a quick primer on what they are. There are 22 amino acids, 8 essential (cannot be made by the body and must be obtained from food) and the remainder non-essential (can be made by the body from other amino acids). You might think of them as construction blocks that come in different sizes and shapes but connect together to form different proteins in the body-50,000 different types of protein in all that comprise of the weight of the human body (minus the water). Clearly, amino acids are the essence of life.

The following can be used as a quick reference when you're having difficulty with a certain aspect of your workout routine (energy levels, focus, growth, etc.) or if you're just looking for ways to improve your overall health and vitality.

The Ultimate Amino Acid List


View all ProSource Brand BCAAs

Amount: Up to 4800 mg (two 2400 mg servings in 2:1:1 ratio of leucine, isoleucine and valine)

Used for:
Muscle protection and growth.

Optimal Use:
30 minutes before and immediately after training. Named for their branch-like structure, these 3 highly regarded aminos may be the most important of them all for preventing muscle tissue breakdown. Your body will also use BCAAs as fuel during intense training. All 3 are considered essential (your body cannot produce them so they need to be obtained from food). Together they represent your best bet for increasing size while holding on to your hard-earned gains. Individually they have specific roles:
  1. L-leucine - The fourth most abundant amino acid found in muscle tissue, leucine is needed in the right ratio to other aminos in the body or you will be unable to utilize the protein you take in. Simply put, if you don't have enough leucine, you can't grow. This is why you'll always see BCAAs offered as a 2:1:1 ratio of leucine, iso-leucine and valine. Some of the critical functions leucine has been noted for are maintaining nitrogen balance (essential for muscle synthesis), preserving glycogen stores and enhancing mental clarity during exercise. Leucine is the more popular of the three for its superior muscle synthesis support, making it a very effective supplement on its own.
  2. L-isoleucine - Endurance, as well as muscle healing and repair, are the benefits associated with isoleucine. And like leucine, isoleucine can also be utilized as an energy source during intense exercise. In fact, studies have indicated that BCAAs may provide 10% of the energy expended during a typical workout.
  3. L-valine - Muscle metabolism, nitrogen balance and muscle tissue repair are some of the more important functions of valine as well as its use as an energy source during intense training.


Amount daily: Up to 20 grams

Used for:
Exercise recovery, growth hormone enhancement, cell hydration, immune system support, anti-catabolic action.

Optimal use:
Immediately after workout (with protein), between meals and before bedtime (preferably on an empty stomach).  L-glutamine is available in two forms, L-glutamine and N-acetyl-L-glutamine. The acetyl version is highly stable during digestion, which increases absorption and makes it more readily available to assist muscle synthesis. Glutamine is classified as a non-essential amino acid (which means it can be manufactured by your body from other aminos) although during times of intense body stress such as weight training or recovery from illness, it becomes conditionally essential and must be obtained from food or supplements to avoid serious depletion. This depletion can occur because glutamine is in very high demand in the body and at the same time comprises over 50% of the amino acids found in skeletal muscle tissue. Therefore, if there's not enough glutamine available for muscle repair after your workout because of other priorities then muscle tissue breakdown is inevitable. And considering glutamine levels are reduced by 50% in the body after a workout it becomes clear that this "non-essential" amino is absolutely necessary for bodybuilders. Glutamine has been shown to increase cell water volume, which in turn facilitates muscle energy and repair. Still another, and one of the more critical functions of L-glutamine is its immune system support, as it is one of the primary precursor compounds in the production of glutathione, the master antioxidant in the body.


Daily amount: Up to 12 grams for arginine; up to 9 grams for arginine-AKG.

Used for:
Muscle growth enhancement, nitric oxide production for muscle "pump" effect, growth hormone enhancement.

Optimal use:
Sustained release caps-3000mg once in the morning on an empty stomach and 3000mg again 30 minutes prior to lunch. Powder: 3000mg before workout and another 3000mg on an empty stomach either in the morning prior to breakfast or afternoon. If you're susceptible to cold sores, take 500mg of L-lysine with arginine.  Arginine is another non-essential amino acid that most bodybuilders would agree is absolutely essential for their workouts. One of the more celebrated supplements in recent years, arginine has shown a remarkable ability to assist in the production of nitric oxide, in turn enhancing blood flow which produces a noticeable "pump" while working out. Arginine also helps preserve lean muscle tissue, stimulates growth hormone release and has a positive effect on raising insulin-like growth factor. All these benefits working together from one amino have established arginine as one of the single most effective (and popular) sports compounds ever for enhancing exercise and producing lean mass. And if this weren't enough, arginine may have a favorable effect on male sexual health and erectile dysfunction as well due to the increased blood flow. Arginine-alpha-ketoglutarate is the more bioavailable and preferred form for its superior muscle pump facilitation and faster anabolic results. Another advantage in the AKG is that because of its high bioavailability only 6 grams per day is needed.

Beta alanine Beta Alanine

Used for: Exercise performance, muscle growth, precursor to carnosine, nitrogen transport.

Amount daily:
2 grams

Optimal use:
20-30 minutes before workout. Take with creatine for best effect.  The amino acid Beta alanine (beta designates an amino acid classification of alanine which can be alpha or beta) has several very crucial roles in protein synthesis (muscle growth). It's also the primary compound that provides the muscles with stored glycogen during workouts as well as transporting nitrogen, the key component for muscle synthesis.1 Perhaps its most important function is as a precursor to the di-peptide carnosine, showing in a four-week study to significantly elevate levels by as much as 66%. This is important because carnosine has demonstrated a lactic acid buffering effect, which may lower the fatigue threshold allowing for a more effective workout. Indeed, this study credited a combination of creatine and beta alanine for higher lactic acid threshold in one study group compared to a control group using creatine alone. If carnosine's the goal, then why not take carnosine? Carnosine is broken down in the digestive tract so that only 40% is left as beta alanine to be re-synthesized as carnosine again, so you'll actually end up with more carnosine in the long run if you take a beta alanine supplement.

Acetyl L-carnitine Acetyl L-Carnitine

Used for: Energy, exercise recovery, weight-loss and focus, anti-catabolic action.

Amount daily:
Up to 2000 mg per day. 

Optimal use:
Up to 1000 mg immediately prior to training. Take any additional pre-workout supplement 1 hour before training so as not to interfere with the absorption of ALC. ALC can also be taken on an empty stomach between meals for energy enhancement and focus support. Do not take with food or other aminos. Aceytl L-carnitine (often referred to as ALC) is a more bioavailable form of the amino acid carnitine, a non-essential amino acid that assists fat metabolism by helping transport free fatty acids into the mitochondria of cells where they can be used as a source of energy. The acetyl version is preferred because it more easily crosses through cell membranes, including the blood-brain barrier making it an excellent brain cell energizer as well. If you need a little focus and pick-me-up during the workday, or any time for that matter, ALC should do the trick, even enhancing mood for many people. ALC is a powerful free-radical scavenger and has also been shown to suppress cortisol, the muscle wasting protein. Studies have validated its energy and muscle recuperative assistance. This along with its fundamental role in helping convert fat to energy makes it one of the most versatile and effective sports supplements available. Of all the amino acids, ALC may be the most effective in supporting weight-loss and energy.

Mega TaurineTaurine

Used for: Increasing cell volume to enhance muscle synthesis, preserve muscle tissue, cell electrolyte balance, blood sugar facilitation.

1000 to 2000 mg per day. 

Optimal use:
Right before workout. NOTE: If your taking ALC and other aminos or protein, take these 20 to 30 minutes before the workout and the ALC just prior to workout for effecitve uptake of both aminos. A conditionally essential amino acid and the second most abundant in muscle tissue, taurine has shown an amazing ability to increase water in the cell which in turn can have a profound effect on muscle synthesis. This hydration effect is due to another very crucial benefit, its electrolyte policing activity, keeping potassium in the cell while removing sodium, which maintains a necessarily proper balance. If you seem to be worn down by dehydration and yet are drinking sufficient amounts of water, taurine may be the answer. Taurine also has an insulin-mimicking effect that can enhance glucose and amino acid utilization and as an anti-catabolic it's been shown to decrease the compound 3-methylhistidine to help preserve muscle tissue.


Used for: Energy and focus.

Up to 2000 mg per day. 

Optimal Use:
Take up to 1000 mg before training. NOTE: start with 500 mg to access tolerance as this amino has a profound energizing effect on some users. Take between meals for additional energy and focus support. Do not take with food or other aminos. L-tyrosine is a non-essential amino acid that is synthesized in the body from another amino acid, phenylalanine. Tyrosine is a precursor to several highly important neurotransmitters including L-dopa (an amino acid with growth hormone enhancing potential), dopamine (a "feel good" compound that's usually released in response to exercise-induced stress), and norepinephrine (a powerful body energizer). Studies have suggested L-tyrosine has a positive effect on mood and may even have efficacy in treating depression. For the athlete, tyrosine can elicit an exhilarating effect with some users reporting considerably more intensity during their workouts, up to 40%. This higher intensity is due in part to increased norepinephrine which has been shown to directly affect the release of glucose from tissue, increase blood flow to muscle and have a positive effect on focus.


Daily amount: 100 to 200 mg 3 times daily.

Used for:
Enhancing mood, relaxation. 

Optimal use:
Start with 100 mg 3 times per day and then increase to 200 mg 3 times per day if needed. Take with or without food. The non-essential amino acid L-theanine is the compound in green tea that creates that relaxed feeling. Research has shown that it does this by stimulating alpha waves in the brain, which produces a state of deep relaxation while at the same time maintaining a high level of alertness, very similar to the effects produced by meditation. L-theanine may also increase levels of the neurotransmitters dopamine and serotonin, both integral to a calm and relaxed attitude. Along with this relaxing effect, L-theanine has shown an ability to lower blood pressure and lessen the jittery feeling experienced from caffeine. L-theanine can be used any time to elicit a feeling of calm and relaxation, but be mindful, you may want to avoid driving after taking it, especially with the first use.

L-Lysine L-Lysine

Daily amount: Up to 2 grams

Used for:
Muscle synthesis support, calcium absorption, energy enhancement, exercise recovery. 

Optimal use:
On an empty stomach-500 milligrams between meals or at bedtime. Stack with arginine and ornithine for increased GH effect. Lysine is an essential amino acid necessary for calcium absorption as well as proper nitrogen balance, which in turn has a positive effect on muscle growth. It is also crucial in the production of hormones, enzymes, and antibodies, and is involved in muscle tissue repair and the formation of collagen to maintain healthy skin. This multi-faceted amino also helps maintain energy levels and assists stress reduction. If these weren't enough, it's also been used as a remedy for cold sores (herpes simplex 1 and 2) and can help facilitate growth hormone, especially when stacked with the next two aminos.

L-Ornithine L-Ornithine

Daily amount: Up to 2 grams.

Used for:
Detoxification, enhancing immune system, liver support, energy enhancement. 

Optimal use:
On an empty stomach-500-1000mg between meals or at bedtime. Stack with arginine and lysine for increased GH effect. Ornithine is a non-essential amino that helps to detoxify ammonia, heal and repair connective tissue, improve liver function and is a precursor to citrulline, which can help to promote energy and enhances the immune system. It's also a growth hormone secretagogue and works most effectively as such with arginine. Ornithine is one of the amino acids (along with arginine and lysine) that have very effective growth hormone potential when taken on an empty stomach (to avoid interference from the absorption of other aminos in food) and this effect can be extended and increased by "stacking" the three. This GH secretion stack is very effective taken 30 minutes prior to a workout or at night before bedtime. The secret to making this method work effectively is to make sure there are as little amino acids in the blood as possible. Which means if you plan on taking this amino stack and another pre-workout product, you should take the amino stack an hour and half before the workout and then your pre-workout product 30 minutes before the workout to avoid any possible conflict as different aminos fight for priority. You can take these three on an empty stomach prior to sleep also for GH enhancement effect.

NAC N-AcetylN-acetyl-cysteine

Daily amount: 1200-1800mg

Used for:
Detoxification, connective tissue support, antioxidant protection. 

Optimal use: 600mg twice daily with meals. N-acetyl cysteine (NAC) is the more stable form of the sulfur-based amino acid and powerful antioxidant cysteine, one of the primary precursor compounds in the production of glutathione, the master antioxidant. Cysteine helps support connective tissue repair while controlling inflammation and also has a very unique ability to clean toxins and detoxify the liver. This last biological action has a very advantageous side benefit as well because its detoxification ability allows cysteine to easily bind to and neutralize acetyldehyde, the toxic chemical and by-product from the consumption of too much alcohol. Plenty of anecdotal evidence will attest to NAC's hangover-relieving power. Here's the trick: right before the drinking festivities start, take 600 milligrams and then take another 600 milligrams before you go to bed. In the morning take another 600mg cap with your hair-of-the-dog and you're good to go. See, amino acids can even help you have fun, or at least help you recover from fun.

Taking Amino Acids

The beauty of aminos is you can take many different types without fear of getting too much of a good thing because they all have distinct pathways and are involved in separate biological processes. Amino acids are best taken with at least 200mg vitamin C and 50mg of B6 to facilitate their uptake and utilization. Most of them are okay to take together except for acetyl-L-carnitine and tyrosine, which should be taken separately on an empty stomach with no other aminos or protein. Don't take glutamine with milk, milk products or protein foods (with the exception of whey protein after workout), as it will interfere with glutamine's absorption. Well there you have it, all the quick reference info you need for the most important amino acid supplements. Refer to this list when ever you want a bit of energy, focus, mood assistance, exercise performance enhancement or lean muscle-even hangover relief-you name it and you're sure to find an amino acid to fit the need.

1) Harris RC, Tallon MJ, Dunnett M, Boobis L, Coakley J, Kim HJ, Fallowfield JL, Hill CA, Sale C, Wise JA. The absorption of orally supplied beta-alanine and its effect on muscle carnosine synthesis in human vastus lateralis. Amino Acids. 2006 Mar 24; [Epub ahead of print]