Sports/Athletic Performance

Mariangela Rondanelli et al. Plasma kinetics of essential amino acids following their ingestion as free formula or as dietary protein components. Aging Clin Exp Res. 2017 Aug;29(4)801-805.

Pasiakos SM. Exercise and amino acid anabolic cell signaling and the regulation of skeletal muscle mass. Nutrients. 2012 Jul;4(7):740-58.
Paddon-Jones D. Amino acid ingestion improves muscle protein synthesis in the young and elderly. Am J Physiol Endocrinol Metab. 2004 Mar;286(3):E321-8.

Esansiyel Amino acid supplementation acutely stimulated muscle protein synthesis in both young and elderly individuals.

Walker DK. Exercise, amino acids, and aging in the control of human muscle protein synthesis. Med Sci Sports Exerc. 2011 Dec;43(12):2249-58

We propose that exercise combined with EAA should be effective not only in improving muscle repair and growth in response to training in athletes, but that strategies such as EAA combined with resistance exercise (or BFR exercise) may be very useful as a counter measure for sarcopenia and other clinical conditions associated with muscle wasting.

Yasutomi Kamei et al. Regulation of Skeletal Muscle Function by Amino Acids. Nutrients. 2020 Jan 19;12(1):261.
Glynn EL. Excess leucine intake enhances muscle anabolic signalling but not net protein anabolism in young men and women. J Nutr. 2010 Nov;140(11):1970-6.

Essential amino acids (EAA) stimulate skeletal muscle protein synthesis (MPS) in humans. Leucine may have a greater stimulatory effect on MPS than other EAA and/or decrease muscle protein breakdown (MPB). We conclude that in 10 g of EAA, the leucine content typical of high-quality proteins (~1.8 g) is sufficient to induce a maximal skeletal muscle protein anabolic response in young adults, but leucine may play a role in autophagy regulation.

Escobar J. Amino acid availability and age affect the leucine stimulation of protein synthesis and eIF4F formation in muscle. Am J Physiol Endocrinol Metab. 2007 Dec;293(6):E1615-21.

Thus, the ability of leucine to stimulate eIF4F formation and protein synthesis in skeletal muscle is dependent on AA availability and age.

Churchward-Venne TA. Leucine supplementation of a low-protein mixed macronutrient beverage enhances myofibrillar protein synthesis in young men: a double-blind, randomized trial. Am J Clin Nutr. 2014 Feb;99(2):276-86.
Paul La Bounty. The effects of oral BCAAs and leucine supplementation combined with an acute lower-body resistance exercise on mTOR and 4E-BP1 activation in humans: preliminary findings. J Int Soc Sports Nutr. 2008; 5(Suppl 1): P21.

Pasiakos SM. Supplemental dietary leucine and the skeletal muscle anabolic response to essential amino acids. Nutr Rev. 2011 Sep;69(9):550-7.

Skeletal muscle protein synthesis (MPS) is regulated by a number of dietary factors, to include essential amino acids (EAAs). These findings suggest that added leucine is unnecessary for the stimulation of MPS when sufficient EAAs are provided.

Robert R Wolfe. The 2017 Sir David P Cuthbertson lecture. Amino acids and muscle protein metabolism in critical care. Clin Nutr. 2018 Aug;37(4):1093-1100.

Use of single amino acids (e.g., leucine), or groups of amino acids (e.g., branched chain amino acids) is ineffective, as all EAAs must be consumed to support a clinically significant increase in protein synthesis.

Regardless of the approach, ensuring an adequate availability of dietary essential amino acids is necessary for pharmacologic therapy to result in an increased rate of protein synthesis.

Tipton KD. NONESSENTIAL AMINO ACIDS ARE NOT NECESSARY TO STIMULATE NET MUSCLE PROTEIN SYNTHESIS IN HEALTHY VOLUNTEERS. J Nutr Biochem. 1999 Feb;10(2):89-95.

Wolfe RR. Regulation of muscle protein by amino acids. J Nutr. 2002 Oct;132(10):3219S-24S. Amino acid availability is a potent regulator of muscle protein synthesis (MPS). A reduction in amino acid availability below basal levels inhibits MPS. INGESTION OF NONESSENTIAL AMINO ACIDS IS NOT NEEDED TO STIMULATE MPS.
Tipton KD. Postexercise net protein synthesis in human muscle from orally administered amino acids. Am J Physiol. 1999 Apr;276(4 Pt 1):E628-34.

Because net balance was similar for Mixed AA and EAA, it does not appear necessary to include nonessential amino acids in a formulation designed to elicit an anabolic response from muscle after exercise. We concluded that ingestion of oral essential amino acids results in a change from net muscle protein degradation to net muscle protein synthesis after heavy resistance exercise in humans similar to that seen when the amino acids were infused.

Wolfe RR. Effects of amino acid intake on anabolic processes. Can J Appl Physiol. 2001;26 Suppl:220-7.

Exercise and exogenous amino acids have an additive effect on muscle protein synthesis. Ingestion of non-essential AAs is not needed to stimulate muscle protein synthesis.

Børsheim E. Essential amino acids and muscle protein recovery from resistance exercise. Am J Physiol Endocrinol Metab. 2002 Oct;283(4):E648-57.

We conclude that NEAA are not necessary for stimulation of NB and that there is a dose-dependent effect of EAA ingestion on muscle protein synthesis.

Robert R Wolfe. Skeletal muscle protein metabolism and resistance exercise. J Nutr. 2006 Feb;136(2):525S-528S.

Importantly, there is an interactive effect between resistance exercise and amino acids, such that the net anabolic response to amino acids following exercise is greater than the sum of the amino acid effects and the exercise effects alone.

Jess A Gwin et al. Muscle Protein Synthesis and Whole-Body Protein Turnover Responses to Ingesting Essential Amino Acids, Intact Protein, and Protein-Containing Mixed Meals with Considerations for Energy Deficit. Nutrients. 2020 Aug 15;12(8):2457.

Robert R Wolfe et al. Factors contributing to the selection of dietary protein food sources. Clin Nutr. 2018 Feb;37(1):130-138.

Mariangela Rondanelli et al. Plasma kinetics of essential amino acids following their ingestion as free formula or as dietary protein components. Aging Clin Exp Res. 2017 Aug;29(4):801-805.

Cuthbertson D. Anabolic signaling deficits underlie amino acid resistance of wasting, aging muscle. FASEB J. 2005 Mar;19(3):422-4.

Moore DR. Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am. J. Clin. Nutr. 2009, 89, 161–168.

Jess A Gwin et al. Effects of high versus standard essential amino acid intakes on whole-body protein turnover and mixed muscle protein synthesis during energy deficit: A randomized, crossover study. Clin Nutr. 2020 Jul 22;S0261-5614(20)30384-8.
Dideriksen K. Influence of amino acids, dietary protein, and physical activity on muscle mass development in humans. Nutrients. 2013 Mar 13;5(3):852-76.
Pasiakos SM. Effects of high-protein diets on fat-free mass and muscle protein synthesis following weight loss: a randomized controlled trial. FASEB J. 2013 Sep;27(9):3837-47.
Svanberg E. Postprandial stimulation of muscle protein synthesis is independent of changes in insulin. Am. J. Physiol. 1997; 272, E841-E847
Volpi E. Contribution of amino acids and insulin to protein anabolism during meal absorption. Diabetes 1996; 45, 1245-1252
Abdulla H. Role of insulin in the regulation of human skeletal muscle protein synthesis and breakdown: a systematic review and meta-analysis. Diabetologia. 2016 Jan;59(1):44-55.

This study demonstrates the complex role of insulin in regulating skeletal muscle metabolism. Insulin appears to have a permissive role in MPS in the presence of elevated AAs, and plays a clear role in reducing MPB independent of AA availability.

Paul GL. The rationale for consuming protein blends in sports nutrition. J Am Coll Nutr. 2009 Aug;28 Suppl:464S-472S.
Dioguardi FS. Wasting and the substrate-to-energy controlled pathway: a role for insulin resistance and amino acids. Am J Cardiol. 2004 Apr 22;93(8A):6A-12A.

Optimization of substrate entry into energy production must also be coupled with sufficient availability of amino acids in ratios suitable for maintaining protein synthesis, inhibiting the catabolic drive, and promoting integrity of cellular protein structures. ALIMENTARY PROTEINS HAVE A CONTENT OF AMINO ACIDS THAT IS FAR FROM THE STOICHIOMETRIC RATIOS OF ESSENTIAL AMINO ACIDS REQUIRED BY HUMANS.

Pasini E. Amino acids: chemistry and metabolism in normal and hypercatabolic states. Am J Cardiol. 2004 Apr 22;93(8A):3A-5A.

Amino acids are the “alphabet” of protein structure, determining many of the properties of proteins. Amino acids are rapidly absorbed and readily available in the blood. In the cell, amino acids maintain protein stores and counteract hormone-mediated catabolic stimuli. Thus, amino acid supplementation may be effective in counteracting the metabolic and morphologic consequences of the hypercatabolic state of chronic diseases such as heart failure, diabetes mellitus, or liver cirrhosis.

Guoyao Wu . Amino acids: metabolism, functions, and nutrition. Amino Acids. 2009 May;37(1):1-17.

In contrast to protein, crystalline AA in the diet do not undergo digestion and are directly available for absorption by the small intestine. Therefore, they are absorbed into enterocytes and appear in the portal vein more rapidly than protein-bound AA.

Valerio A. Branched-chain amino acids, mitochondrial biogenesis, and health span: an evolutionary perspective. Aging (Albany NY). 2011 May;3(5):464-78.
Dioguardi FS. Clinical use of amino acids as dietary supplement: pros and cons. J Cachexia Sarcopenia Muscle. 2011 Jun;2(2):75-80. Epub 2011 Jun 11.
Ohtani M. Amino acid mixture improves training efficiency in athletes. J Nutr. 2006 Feb;136(2):538S-543S
Dorofeyeva EE. Biochemical and heart adaptations to physical training and supplementation with amino acids. J Strength Cond Res. 2004 Nov;18(4):738-40.

Histological data from a secondary study of actual heart tissue showed that the amino acids supplementation may have inhibiting effects on myocardial apoptosis. The criteria of efficiency of the amino acids supplementation were defined by the albumin, IL-6, and IL-10 concentrations.

Kingsbury KJ. Contrasting plasma free amino acid patterns in elite athletes: association with fatigue and infection. Br J Sports Med. 1998 Mar;32(1):25-32
Portier H. Effects of branched-chain amino acids supplementation on physiological and psychological performance during an offshore sailing race. Eur J Appl Physiol. 2008 Nov;104(5):787-94.
Greer BK. Branched-chain amino acid supplementation and indicators of muscle damage after endurance exercise. Int J Sport Nutr Exerc Metab. 2007 Dec;17(6):595-607.
Spradley BD. Ingesting a pre-workout supplement containing caffeine, B-vitamins, amino acids, creatine, and beta-alanine before exercise delays fatigue while improving reaction time and muscular endurance. Nutr Metab (Lond). 2012 Mar 30;9:28.
Allyson L Walsh. Improved time to exhaustion following ingestion of the energy drink Amino Impact. J Int Soc Sports Nutr. 2010; 7: 14.
Wiśnik P. The effect of branched chain amino acids on psychomotor performance during treadmill exercise of changing intensity simulating a soccer game. Appl Physiol Nutr Metab. 2011 Dec;36(6):856-62.

It is concluded that BCAA supplementation might be recommended in sport activities that change in intensity and require quick responses to external signals (e.g., soccer and other team games).

Negro M. Branched-chain amino acid supplementation does not enhance athletic performance but affects muscle recovery and the immune system. J Sports Med Phys Fitness. 2008 Sep;48(3):347-51.

The BCAA also modifies the pattern of exercise-related cytokine production, leading to a diversion of the lymphocyte immune response towards a Th1 type. According to these findings, it is possible to consider the BCAA as a useful supplement for muscle recovery and immune regulation for sports events.

Shigeo Kawada et al. Cystine and theanine supplementation restores high-intensity resistance exercise-induced attenuation of natural killer cell activity in well-trained men. J Strength Cond Res. 2010 Mar;24(3):846-51.

Therefore, in practical application, CT supplementation would be useful for athletes to restore the attenuation of NK cell activity during high-intensity and high-frequency training

Shigeki Murakami et al. Suppression of exercise-induced neutrophilia and lymphopenia in athletes by cystine/theanine intake: a randomized, double-blind, placebo-controlled trial. J Int Soc Sports Nutr. 2010; 7: 23.

CT supplementation significantly attenuated the increase in neutrophil count and the reduction in lymphocyte count induced by intense endurance exercise. These results suggest that CT supplementation may suppress the exercise-induced fluctuation of the blood immunocompetent cells and may help to reduce the alteration of the immune state.

Christos S Katsanos et al. Essential amino acid ingestion as an efficient nutritional strategy for the preservation of muscle mass following gastric bypass surgery. Nutrition. 2016 Jan;32(1):9-13.

Changing current dietary practices towards increasing ingestion of essential amino acids provides an approach that can potentially prevent loss of lean body tissue and ultimately achieve a more sustained level of health in patients that have undergone gastric bypass.

Buonocore D. Anti-inflammatory Dietary Interventions and Supplements to Improve Performance during Athletic Training. J Am Coll Nutr. 2015;34 Suppl 1:62-7.

Nutrition can influence exercise-induced immune suppression. Elite athletes competing at the highest levels can benefit from nutritional and supplementation support to improve immunity and reduce acute and chronic inflammations.

Jousse C. Physiological concentration of amino acids regulates insulin-like-growth-factor-binding protein 1 expression. Biochem. J. 1998 Aug 15; 334, 147-153

Svanberg E. Postprandial stimulation of muscle protein synthesis is independent of changes in insulin. Am. J. Physiol. 1997; 272, E841-E847

Insaf Berrazaga et al. The Role of the Anabolic Properties of Plant- versus Animal-Based Protein Sources in Supporting Muscle Mass Maintenance: A Critical Review. Nutrients. 2019 Aug; 11(8): 1825.