Tag Archives: Amino Acids

A Terrific Trio – The BCAAs

by Livia Ly.  For those who don’t know exactly what Branched Chain Amino Acids (BCAAs) are, here you Pills eating pillsgo: they include the amino acids valine, leucine and isoleucine.  They are part of the family of essential amino acids in which leucine plays the key role in promoting muscle protein anabolism, or synthesis.  For those who are active and looking to increase performance and perhaps muscle mass, BCAAs may be worth taking.  Here’s the short story of how the BCAAs might act as an ergogenic aid.  During prolonged exercise, plasma tryptophan (another amino acid) rises resulting in feelings of fatigue.  Research, however, shows that if you consume BCAAs, it may compete with free tryptophan; thus reducing your perception of fatigue.  The result is that less tryptophan goes to your brain, you get less fatigued, and experience higher performance!    Interesting…The effective dose is ~5 to 20 g.  This can still be easily reached with protein-rich foods; however, the data on BCAAs regarding its ergogenic properties are on the three amino acids as a stand-alone supplement (not as part of a food).

So are there benefits for weight trainers? 

Yep.  BCAA supplementation before/after exercise may help with the muscle pain and damage that you get from lifting all that weight.  Plus, it may promote muscle building, especially if you are brand new to the weight lifting world.  Besides, BCAA supplementation before exercise may also help slow down the breakdown of muscle during exercise; also, there is some good data showing that BCAAs can reduce DOMS or delayed onset muscle soreness. However, of the three BCAAs, leucine may be the most important.bcaa-blends-main

Why leucine?

Significant decreases in blood leucine occur after aerobic (11 to 33%), anaerobic lactic (5 to 8%) and strength (30%) exercises.  New research from Brazil done by Humberto Nicastro and colleagues, published in March 2014, showed that BCAA/leucine and HMβ are effective supplements in the lessening of muscle damage that is caused by exercise.  By the way – hydroxy-methyl butyrate, or HMβ, is formed via leucine.

I interviewed Dr Nicastro, who is a dietitian in Brazil and coordinator of the VP Research Institute, and asked what he recommends for pre/post exercise in terms of BCAA and leucine. “An adequate amount of protein guarantees the maximum threshold of leucine in the blood.  So if you opt for proteins, there is no need to combine with leucine.  Although there may be a small advantage over the low protein content of leucine (casein, soy, rice).  But even so, if the total dose is corrected for the content of leucine, the effect is comparable,” he said. Dr Nicastro finalized his recommendations by saying “I recommend BCAA/leucine or protein for pre-workout to ease muscle damage during training and for after training to increase muscle synthesis.”

Alright, let’s summarize.  Here are my four must-dos:

1-     Before exercise.  Eating 3 to 6 g of essential amino acids before exercise may help you minimize muscle damage and breakdown.

–        Whey: just so you know, about 25% of all whey protein is made up of BCAAs, which is a substantial amount.

2-     Don’t forget your post-workout snacks!  BCAAs work best building up your muscles when you include them with foods that are rich in protein and carbohydrates after your exercise.

3-     Leucine at each meal.  It’s recommended to eat at least 2 g of leucine with each meal, or a minimum of 8 g per day.

–        Whey contains 10% of leucine.  If you drink a shake with 25 g of protein, you will be getting 2.5 g of leucine.

4-     BCAAs for your endurance exercises.  For those of you who love to exercise for long periods of time – you need to eat 6 to 10 g per hour of BCAAs with sports drinks, so you can delay that fatigue that keeps bothering you.


  1. Balage M, Dardeveta D. Long-term effects of leucine supplementation on body composition. Curr Opin Clin Nutr Metab Care. 2010,13:265–270.
  2. Bishop D. Dietary supplements and team-sport performance. Sports Med. 2010,40(12):995-1017.
  3. Campbell B et al. International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr. 2007,4:8.
  4. Da Luz C et al. Potential therapeutic effects of branched-chain amino acids supplementation on resistance exercise-based muscle damage in humans. J Int Soc Sports Nutr. 2011,8:23.
  5. Kreider RB et al. ISSN exercise & sport nutrition review: research & recommendations. J Int Soc Sports Nutr. 2010,7:7.   
  6. Mero A. Leucine supplementation and intensive training. Sports Med. 1999,27(6):347-358.
  7. Nicastro H et al. Are the bcaas/leucine supplementation effects on exercise-induced muscle damage related immunity response or to Hmβ? J Nutrition Health Food Sci. 2014,2(2):1-3.
  8. Nicastro H et al. Does branched-chain amino acids supplementation modulate skeletal muscle remodeling through inflammation modulation? Possible mechanisms of action. J Nutr Metab. 2012 (2012).
  9. Pasiakos SM, McClung JP. Supplemental dietary leucine and the skeletal muscle anabolic response to essential amino acids. Nutr Rev. 2011,69(9):550–557.
  10. Sharp CP, Pearson DR. Amino acid supplements and recovery from high-intensity resistance training. J Strength Cond Res. 2010,24(4):1125-30.
  11. Shimomura Y et al. Nutraceutical effects of branched-chain amino acids on skeletal muscle. J. Nutr. 2006,136:529S–532S.
  12. Symons TB et al. Aging does not impair the anabolic response to a protein-rich meal. Am J Clin Nutr. 2007;86:451–6.
  13. TeamUSA.org. Branched chain amino acids, 2010. At http://bit.ly/1mvdtwC
  14. Volek JS. Leucine triggers muscle growth. Nutrition Express. At http://bit.ly/1jNm3Dv

Livia LyLivia Ly head shot

I’m a health enthusiast.

I’m a dietitian trained in Brazil.

I’m a nutrition grad student in Chicago.


The Best Damn Protein Book Ever!

Dietary supplement companies and the food industry spend millions to reach resistance trainers—often with exaggerated 51Uiq-KGCNL._SY344_BO1,204,203,200_marketing messages—while health practitioners continue to counsel athletes that their interest in protein is misguided and even dangerous. There appears to be a disconnect between scientists and almost everyone else in sports nutrition. With so much conflicting information, it’s difficult to know who to believe. With contributions from the world’s foremost experts, Dietary Protein and Resistance Exercise delivers the uncut scientific truth about the role of dietary protein in the well-being of athletes.

Updating and clarifying the issues surrounding purposeful protein intake and resistance trainers, this volume:

  • Reviews the science-related history of protein and its consumption among strength athletes
  • Analyzes the mechanisms behind what proteins do in muscle cells
  • Describes protein’s effect on performance, recovery, and body composition
  • Explores various populations that actively employ resistance training and dietary protein
  • Discusses timing, type, and safety data regarding liberal protein diets and related supplements
  • Includes sidebars, practical examples, and case studies—translating the science into a practical understanding of various protein-related topics

Separating fact from fiction and providing the hard science behind the numbers, this volume demonstrates how changes in dietary protein intake may lead to measurable improvements in body composition, energy levels, and athletic performance.

Save 20% + Free Shipping when you order directly from CRC Press:  Discount Code 888FX at checkout.


Table of Contents

Chapter 1 Dietary Protein and Strength Exercise: Historical Perspectives

Peter W. R. Lemon

Chapter 2 Protein Metabolism: Synthesis and Breakdown on a Cellular Level

Layne E. Norton, Gabriel J. Wilson, and Jacob M. Wilson

Chapter 3 The Safety Debate Regarding Dietary Protein in Strength Athletes

Lonnie M. Lowery

Chapter 4 Dietary Protein Efficacy: Dose and Peri-Exercise Timing

Joshua Cotter and David Barr

Chapter 5 Dietary Protein Efficacy: Dietary Protein Types

Bill Campbell

Chapter 6 Weight Control with Dietary Protein

Ronald Mendel

Chapter 7 Protein, Resistance Training, and Women

Dawn Anderson and Christin Dietz-Seher

Chapter 8 Protein’s Effects on Rehabilitation and the Sarcopenia of Aging

Troy Smurawa

Chapter 9 Nitrogenous Compounds and Supplements

Jamie Landis, Tim N. Ziegenfuss, and Hector L. Lopez

Chapter 10 Case Studies and Sports Application

Michael T. Nelson, Jonathan N. Mike, and David Barr

Editor BIOs

Lonnie M. Lowery, PhD, RD, is a professor of nutrition and exercise physiology of 11 years, currently at Winona State University, and president of Nutrition, Exercise and Wellness Associates Ltd. With formal training in both exercise physiology and nutrition he has published in academic and research settings on various sports nutrition topics such as dietary proteins, fats, antioxidants, dietary supplements, and overtraining. Dr. Lowery has also served as an educational, scientific, and product development consultant for a number of large dietary supplement companies such as Met Rx, Bodyonics-Pinnacle, and Biotest Laboratories. As an award-winning mentor and educator, he has written hundreds of lay articles for the strength and fitness communities and co-hosts www.IronRadio.org, a free educational and consumer advocacy podcast on iTunes.

Jose Antonio, PhD, is the chief executive officer and cofounder of the International Society of Sports Nutrition (www.theissn.org); furthermore, he is a Fellow of the American College of Sports Medicine and National Strength and Conditioning Association (NSCA). He was the 2005 recipient of the NSCA Research Achievement Award and the 2009 NSCA Educator of the Year.  Dr. Antonio is the editor-in-chief of Sports Nutrition Insider, and Inside Fitness magazine, and has contributed to Ironman, Muscular Development, Muscle and Fitness, and Fitness Rx Men/Women. He is an assistant professor at Nova Southeastern University in Fort Lauderdale, Florida.

How Much Protein the Body Can Use in a Single Meal?

By Alan Aragon

(Note: this article was originally posted at: www.wannabebig.com )


Protein-Diets-for-Weight-LossA longstanding belief in fitness circles is that the body can only use a certain amount of protein per meal, and the excess is either oxidized or excreted. The ballpark range thrown around is 20-30 grams, with 30 grams being perhaps the most common figure.  This guideline has led many trainees to go through the pains of consuming multiple doses of protein throughout the day, banking that it will maximize muscle anabolism or muscle retention.  Well, true or not, this concept fits in nicely with another longstanding fitness “rule” that you have to eat at least six times per day in order to keep the body’s metabolism revving high. Since the meal frequency and metabolism dogma has been thoroughly debunked [1-5], it’s time to dig into the topic of whether there’s a limit to effective protein dosing, and if so, what that limit might be. 

Looking at simple logic first

Let’s imagine an experiment involving two relatively lean 200 lb individuals. For the purposes of this illustration, I’ll assign a daily amount of protein known to adequately support the needs of the athletic population. We’ll give Person A 150 g protein spread over five meals at 30 g each. We’ll give Person B the same amount of protein, but in a single meal. Let’s say that this meal consists of a 16 oz steak, chased with a shake containing two scoops of protein powder. If we really believed that only 30 g protein can be handled by the body in a single meal, then Person B would eventually run into protein deficiency symptoms because he supposedly is only absorbing a total of 30 g out of the 150 g we’re giving him. At 30 g/day, he’s only getting 0.33 g/kg of bodyweight, which isn’t even half of the already-low RDA of 0.8 g/kg. If the body worked this way, the human species would have quickly become extinct. The human body is more efficient and effective than we give it credit for. The body will take all the sweet time it needs to effectively digest and absorb just about whatever dose you give it. Person A will have shorter digestion periods per meal in order to effectively absorb and utilize the small meals. Person B will have a longer digestion period in order to effectively absorb and utilize the large meal. While the truth in this logic seems self-evident, the important question is whether or not it’s supported by scientific research. Let’s look at the evidence, starting with immediate-effect (acute) studies, then move on to the longer-term trials.

Research examining speed of absorption

A thorough literature review by Bilsborough and Mann compiled data from studies by various investigators who measured the absorption rates of various protein sources [6]. Oddly, an amino acid mixture designed to mimic the composition of pork tenderloin made the top spot, at 10 g/hour, while whey took a close second at 8-10 g/hour. Other proteins fell in their respective spots below the top two, with little rhyme or reason behind the outcomes. As a matter of trivia, raw egg protein was the most slowly absorbed of them all at 1.3 g/hour. It’s important to note that these data have some serious limitations. A major one is the variance of the methods used to determine the absorption rates (i.e., intravenous infusion, oral ingestion, ileal ingestion). Most of the methods are just too crude or far-fetched for serious consideration. Another limitation is that these figures could be skewed depending upon their concentration in solution, which can affect their rate of gastric evacuation. Another factor to consider is the timing of ingestion relative to exercise and how that might differentially affect absorption rates. Finally, short-term data leaves a lot open to question.high-protein-diet

Short-term research supporting the magic limit

I’ve heard many folks parrot that the maximal anabolic effect of a single protein dose is limited to 20 grams, citing recent work by Moore and colleagues [7]. In this study’s 4-hour post-exercise test period, 40 g protein did not elicit a greater anabolic response than 20 g. I’d interpret these outcomes with caution. Fundamentally speaking, protein utilization can differ according to muscle mass. The requirements of a 140-lb person will differ markedly from someone who’s a lean 200. Additionally, a relatively low amount of total volume was used (12 sets total). Typical training bouts usually involve more than one muscle group and are commonly at least double that volume, which can potentially increase the demand for nutrient uptake. Finally, the conclusion of the authors is questionable. They state explicitly,

“…we speculate that no more than 5-6 times daily could one ingest this amount (~20 g) of protein and expect muscle protein synthesis to be maximally stimulated.”

So, they’re implying that 100-120 grams of protein per day is maximal for promoting muscle growth. Wait a minute, what? Based on both the bulk of the research evidence and numerous field observations, this is simply false [8,9].  In another recent study, Symons and colleagues compared the 5-hour response of a moderate serving of lean beef containing 30 g protein with a large serving containing 90 g protein [10]. The smaller serving increased protein synthesis by approximately 50%, and the larger serving caused no further increase in protein synthesis, despite being triple the dose. The researchers concluded that the ingestion of more than 30 g protein in a single meal does not further enhance muscle protein synthesis. While their conclusion indeed supports the outcomes of their short-term study, it’s pretty easy to predict the outcomes in muscle size and strength if we compared a total daily protein dose of 90 g with 30 g over a longer trial period, let alone one involving a structured exercise protocol. This brings me to the crucial point that acute outcomes merely provide grounds for hypothesis. It’s not completely meaningless, but it’s far from conclusive without examining the long-term effects.

Longer-term research challenging the magic limit

If we were to believe the premise that a 20-30 g dose of protein yields a maximal anabolic effect, then it follows that any excess beyond this dose would be wasted. On the contrary, the body is smarter than that. In a 14-day trial, Arnal and colleagues found no difference in fat-free mass or nitrogen retention between consuming 79% of the day’s protein needs (roughly 54 g) in one meal, versus the same amount spread across four meals [11].  Notably, this study was done on young female adults whose fat-free mass averaged 40.8 kg (89.8 lb). Considering that most non-sedentary males have considerably more lean mass than the female subjects used in the aforementioned trial, it’s plausible that much more than 54 g protein in a single meal can be efficiently processed for anabolic and/or anti-catabolic purposes. If we extrapolated the protein dose used in this study (79% of 1.67g/kg) to the average adult male, it would be roughly 85-95 g or even more, depending on just how close someone is to the end of the upper limits of muscular size.  When Arnal and colleagues applied the same protocol to the elderly population, the single-dose treatment actually caused better muscle protein retention than the multiple-dose treatment [12].  This raises the possibility that as we age, larger protein feedings might be necessary to achieve the same effect on protein retention as lesser amounts in our youth.

Intermittent Fasting research nailing the coffin shut?

Perhaps the strongest case against the idea of a dosing limit beyond which anabolism or muscle retention can occur is the recent intermittent fasting (IF) research, particularly the trials with a control group on a conventional diet. For example, Soeters and colleagues compared two weeks of IF involving 20-hour fasting cycles with a conventional diet [13].  Despite the IF group’s consumption of an average of 101 g protein in a 4-hour window, there was no difference in preservation of lean mass and muscle protein between groups. In another example, Stote and colleagues actually reported an improvement in body composition (including an increase in lean mass) after 8 weeks in the IF group consuming one meal per day, where roughly 86 g protein was ingested in a 4-hour window [14]. Interestingly, the conventional group consuming three meals spread throughout the day showed no significant body composition improvements.  Keep in mind that bioelectrical impedance (BIA) was used to determine body composition, so these outcomes should be viewed with caution. I’ve been highly critical of this study in the past, and I still am. Nevertheless, it cannot be completely written off and must be factored into the body of evidence against the idea of a magic protein dose limit.

Conclusion & application

Based on the available evidence, it’s false to assume that the body can only use a certain amount of protein per meal. Studies examining short-term effects have provided hints towards what might be an optimal protein dose for maximizing anabolism, but trials drawn out over longer periods haven’t supported this idea. So, is there a limit to how much protein per meal can be effectively used? Yes there is, but this limit is variety-of-protein-sourceslikely similar to the amount that’s maximally effective in an entire day. What’s the most protein that the body can effectively use in an entire day? The short answer is, a lot more than 20-30 g. The long answer is, it depends on several factors. In most cases it’s not too far from a gram per pound in drug-free trainees, given that adequate total calories are provided [8,9].  In terms of application, I’ve consistently observed the effectiveness of having approximately a quarter of your target bodyweight in both the pre- and post-exercise meal. Note: target bodyweight is a surrogate index of lean mass, and I use that to avoid making skewed calculations in cases where individuals are markedly over- or underweight. This dose surpasses the amounts seen to cause a maximal anabolic response but doesn’t impinge upon the rest of the day’s protein allotment, which can be distributed as desired. On days off from training, combine or split up your total protein allotment according to your personal preference and digestive tolerance. I realize that freedom and flexibility are uncommon terms in physique culture, but maybe it’s time for a paradigm shift.  In sum, view all information – especially gym folklore and short-term research – with caution. Don’t buy into the myth that protein won’t get used efficiently unless it’s dosed sparingly throughout the day. Hopefully, future research will definitively answer how different dosing schemes with various protein types affect relevant endpoints such as size and strength. In the mean time, feel free to eat the whole steak and drink the whole shake, and if you want to get the best bang for your buck, go for a quality protein blend such as Nitrean (http://www.atlargenutrition.com/products/nitrean-46)


alan-coach-mug-e1392796548403Alan Aragon has over 15 years of success in the fitness field. He earned his Bachelor and Master of Science in Nutrition with top honors. Alan is a continuing education provider for the Commission on Dietetic Registration, National Academy of Sports Medicine, American Council on Exercise, and National Strength & Conditioning Association. Alan recently lectured to clinicians at the FDA and the annual conference of the Los Angeles Dietetic Association.  He maintains a private practice designing programs for recreational, Olympic, and professional athletes, including the Los Angeles Lakers, Los Angeles Kings, and Anaheim Mighty Ducks. Alan is a contributing editor and Weight Loss Coach of Men’s Health magazine.  His book Girth Control is considered one of the most in-depth manuals for physique improvement and understanding nutrition for fitness & sports. Last but not least, Alan writes a monthly research review providing of the latest science on nutrition, training, and supplementation. Visit Alan’s blog to keep up with his latest shenanigans.  For more information, go to www.alanaragonblog.com   


1. Smeets AJ, Westerterp-Plantenga MS. Acute effects on metabolism and appetite profile of one meal difference in the lower range of meal frequency. Br J Nutr. 2008 Jun;99(6):1316-21.

2. Taylor MA, Garrow JS. Compared with nibbling, neither gorging nor a morning fast affect short-term energy balance in obese patients in a chamber calorimeter. Int J Obes Relat Metab Disord. 2001 Apr;25(4):519-28.

3. Bellisle F, McDevitt R, Prentice AM. Meal frequency and energy balance. Br J Nutr. 1997 Apr;77 Suppl 1:S57-70.

4. Verboeket-van de Venne WP, Westerterp KR. Frequency of feeding, weight reduction and energy metabolism. Int J Obes Relat Metab Disord. 1993 Jan;17(1):31-6.

5. Verboeket-van de Venne WP, Westerterp KR. Influence of the feeding frequency on nutrient utilization in man: consequences for energy metabolism. Eur J Clin Nutr. 1991 Mar;45(3):161-9.

6. Bilsborough S, Mann N. A review of issues of dietary protein intake in humans. Int J Sport Nutr Exerc Metab. 2006 Apr;16(2):129-52.

7. Moore DR, et al. Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am J Clin Nutr. 2009 Jan;89(1):161-8.

8. Campbell B, et al. International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr. 2007 Sep 26;4:8.

9. Tipton KD, Wolfe RR. Protein and amino acids for athletes. J Sports Sci. 2004 Jan;22(1):65-79.

10. Symons TB, et al. A moderate serving of high-quality protein maximally stimulates skeletal muscle protein synthesis in young and elderly subjects. J Am Diet Assoc. 2009 Sep;109(9):1582-6.

11. Arnal MA, et al. Protein feeding pattern does not affect protein retention in young women. J Nutr. 2000 Jul;130(7):1700-4.

12. Arnal MA, et al. Protein pulse feeding improves protein retention in elderly women. Am J Clin Nutr. 1999 Jun;69(6):1202-8.

13. Soeters MR, et al. Intermittent fasting does not affect whole-body glucose, lipid, or protein metabolism. Am J Clin Nutr. 2009 Nov;90(5):1244-51.

14. Stote KS, et al. A controlled trial of reduced meal frequency without caloric restriction in healthy, normal-weight, middle-aged adults. Am J Clin Nutr. 2007 Apr;85(4):981-8


Beta-Alanine: One Kick-A$$ Amino Acid

By: Jeffrey R. Stout, Ph.D., CSCS, FISSN, FNSCA
Date Published: May 2011

Summary: Beta-alanine supplementation (3.2g to 6.4g per day) may elevate skeletal muscle carnosine levels and enhance exercise performance in untrained subjects. Future studies need to examine whether beta-alanine supplementation can increase skeletal muscle carnosine levels and exercise performance in trained athletes as well as determine the combined effect of beta-alanine supplementation and training on performance.

Beta-alanine is a non-essential amino acid that is common in many foods that we eat, such as chicken. Beta-alanine is not much of an ergogenic aid by itself. However, when it enters the muscle cell, it becomes the rate limiting substrate to carnosine synthesis (1). In fact, Harris (2) reported that 4 weeks of supplementing beta-alanine (4 to 6 grams per day) resulted in a mean increase of 64% in skeletal muscle. Supplementing L-carnosine can also increase skeletal muscle carnosine concentrations. Once L-carnosine enters the digestive system, it is hydrolyzed into histidine and beta-alanine, which is then taken up by skeletal muscle and synthesized into carnosine (2). Due to the immediate hydrolysis, carnosine can not be taken up into the muscle intact.

Carnosine, found primarily in fast-twitch skeletal muscle, contributes to buffering of H+ thus attenuating a drop in pH associated with anaerobic metabolism. Interestingly, carnosine concentrations in athletes, such as sprinters, appear to be significantly higher than those of marathoners, untrained individuals, and the elderly (2). Furthermore, intense physical training is capable of increasing muscle carnosine levels. Twelve days of intense training of elite speed skaters has been shown to increase muscle carnosine content by 87% (2).

Suzuki et al. (5) recently examined the relationship between skeletal muscle carnosine levels and high intensity exercise performance. Suzuki et al. (5) reported there was a significant relationship between carnosine concentration and the mean power from a 30 second maximal sprint on a cycle ergometer. Basically, the higher the carnosine, the better the performance. In theory, increasing skeletal muscle carnosine levels (via beta-alanine supplementation or intense training) should increase buffering capacity, delay fatigue, and increase exercise performance.

Recently Hill et al. (3) examined the effect of beta-alanine supplementation on muscle carnosine levels and exercise performance in untrained subjects. In double blind fashion, twenty male subjects (19-31yrs) were supplemented either 4.0g beta-alanine or sugar placebo for the first week, then up to 6.4g for an additional 9 weeks. Muscle carnosine levels (via muscle biopsy) and work done were measured at weeks 0, 4, and 10 during cycling to exhaustion at 110% of estimated power max. Mean carnosine levels increased by 58% at week 4 and an additional 15% at week 10. Further, there was about a 16% increase in total work done during cycle ergometry at weeks 4 and 10.

In another study, Stout et al. (4) examined the effects of beta-alanine supplementation on physical working capacity at fatigue threshold (PWCFT) in untrained young men. In double blind fashion, subjects consumed either 1.6g of beta-alanine or sugar placebo four times per day for six days, then 3.2 grams per day 22 days. Prior to and following supplementation, the subjects performed an incremental cycle ergometry test to determine PWCFT, which was determined from bipolar surface electromyography recorded from the vastus lateralis muscle. The results revealed a significantly greater increase in PWCFT of 9% over placebo. The findings suggest that beta-alanine supplementation for 28 days may delay the onset of neuromuscular fatigue.

In conclusion, beta-alanine supplementation (3.2g to 6.4g per day) appears to elevate muscle carnosine levels and enhance exercise performance in untrained subjects. Future studies need to examine whether beta-alanine supplementation can increase muscle carnosine levels and exercise performance in highly trained athletes. Further, future investigations should also examine the combined effect of beta-alanine supplementation and training on performance.



1. Dunnett M., R. C. Harris. Influence of oral beta-alanine and L-histidine supplementation on the carnosine content of the gluteus medius. Equine Vet J. 30(Suppl): 499-504, 1999.
2. Harris R. C. Muscle carnosine elevation with supplementation and training, and the effects of elevation on exercise performance. (Presented at the International Society of Sports Nutrition Annual conference, 2005, New Orleans.).
3. Hill C. A., R. C. Harris, H. J. Kim, L. Boobis, C. Sale, J. A. Wise. Theffect of beta-alanine and creatine monohydrate supplementation on muscle composition and exercise performance. (Presented at the American College of Sports Medicine Annual conference, 2005, Nashville.)
4. Stout J. R., J. O’Kroy, M. Mielke, R. Zoeller, D. Torok, J.T. Cramer, and B. S. Graves. Effects of 28 days of beta-alanine and creatine monohydrate supplementation on physical working capacity at neuromuscular fatigue threshold. (Presented at the International Society of Sports Nutrition Annual conference, 2005, New Orleans.).
5. Suzuki Y., I. Osamu, N. Mukai, H. Takahashi, and K. Takamatsu. High level of skeletal muscle carnosine contributes to the latter half of exercise performance during 30-s maximal cycle ergometer sprinting. Jap. J. Physiol. 52:199-200. 2002.