Supplement Reviews: Essential Amino Acids!

Amino acids are the building blocks of protein. Of the 20 amino acids that make up dietary protein, 9 are essential and 11 are non-essential.

What Is It?

Essential Amino Acids - Amino acids are the building blocks of protein. Of the 20 amino acids that make up dietary protein, 9 are essential and 11 are non-essential.

Essential Non-essential
Histidine Alanine
Isoleucine Arginine
Leucine Aspartic Acid
Lysine Cysteine
Methionine Tyrosine
Phenylalanine Glutamic Acid
Tryptophan Glutamine
Valine Glycine
Threonine  Asparagine

An amino acid is considered essential because the body cannot make it from other dietary components. Therefore if one's diet does not contain a full complement of the essential amino acids, a nutritional deficiency exists.

What Does It Do?

During exercise, protein breakdown increases with no rise in protein synthesis. This means that training and competing can be very catabolic times, no matter what type of exercise you do. Fortunately, during the post-exercise period, this muscle catabolism can be slowed as protein synthesis begins to rise.

However, this increase still isn't enough to counter the protein breakdown that's still occurring. The net result of this workout and post workout catabolism is that muscle recovery and improvement (if endurance exercise is your thing) or growth (if strength exercise is your thing) is hampered.

Current research in dietary supplementation has targeted these catabolic times, attempting to minimize the catabolism and maximize the anabolism (including recovery, improvement, and/or growth). This research has demonstrated that essential amino acids (alone or with carbohydrates) ingested before, during, or after exercise promote huge increases in protein balance.

Where Does It Come From?

Essential Amino Acids are basic dietary components that comprise all of the proteins we eat. However, the provision of these amino acids individually (or as part of an easily digestible complete protein like hydrolyzed or isolated whey protein) can lead to more rapid digestion and absorption and faster recovery.

Furthermore, 3 of the 9 essential amino acids are the often-discussed branched chain amino acids (BCAA). These amino acids are important to muscle metabolism and may prevent central fatigue.

How Do I Use It?

Strength and endurance athletes will benefit from approximately 6g per 70kg mass of EAA ingested immediately prior to and/or during exercise.

Alternatively, athletes could choose to consume 0.4g/kg of rapidly digesting protein like whey hydrolysate or whey concentrate/isolate. For further benefit add 0.8g/kg carbohydrate to enhance the recovery effects of these amino acids.

Credibility Rating:

Rating Scale:

4/4 - This supplement/regimen has significant scientific backing and can produce significant benefits in most individuals.

3/4 - There exists a sound theoretical basis for its ergogenic effects; may work in certain individuals; further research is needed to elucidate their respective effects.

2/4 - Science is equivocal, animal data and human data may be conflicting; or mechanism of action may be unclear.

1/4 - Little or no science as well as poor theoretical foundation.

Scientific References:

  • Biolo, G., B. D. Williams, R. Y. Fleming, and R. R. Wolfe. Insulin action on muscle protein kinetics and amino acid transport during recovery after resistance exercise. Diabetes 48: 949-957, 1999.
  • Borsheim, E., K. D. Tipton, S. E. Wolf, and R. R. Wolfe. Essential amino acids and muscle protein recovery from resistance exercise. Am.J.Physiol Endocrinol.Metab 283: E648-E657, 2002.
  • Levenhagen, D. K., J. D. Gresham, M. G. Carlson, D. J. Maron, M. J. Borel, and P. J. Flakoll. Postexercise nutrient intake timing in humans is critical to recovery of leg glucose and protein homeostasis. Am.J.Physiol Endocrinol.Metab 280: E982-E993, 2001.
  • Rasmussen, B. B., K. D. Tipton, S. L. Miller, S. E. Wolf, and R. R. Wolfe. An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise. J.Appl.Physiol 88: 386-392, 2000.
  • Roy, B. D. and M. A. Tarnopolsky. Influence of differing macronutrient intakes on muscle glycogen resynthesis after resistance exercise. J.Appl.Physiol 84: 890-896, 1998.
  • Tipton, K. D., A. A. Ferrando, S. M. Phillips, D. Doyle, Jr., and R. R. Wolfe. Postexercise net protein synthesis in human muscle from orally administered amino acids. Am.J.Physiol 276: E628-E634, 1999.
  • Tipton, K. D., B. B. Rasmussen, S. L. Miller, S. E. Wolf, S. K. Owens-Stovall, B. E. Petrini, and R. R. Wolfe. Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. Am.J.Physiol Endocrinol.Metab 281: E197-E206, 2001.
  • Tipton, K. D., E. Borsheim, S. E. Wolf, A. P. Sanford, and R. R. Wolfe. Acute response of net muscle protein balance reflects 24-h balance after exercise and amino acid ingestion. Am.J.Physiol Endocrinol.Metab 284: E76-E89, 2003.