Jack3D, MusclePharm Assault, Muscle Tech Neuro Core, 1.M.R. or Craze. These are just some of the top selling supplements on the market that fall within the highly scrutinized category of pre-work out supplements. Pre-work out supplements are essentially performance enhancing supplements, supposedly offering increased stamina, improved energy production and decreased fatigue during a workout. Avid users often describe their effects as like "an injection of energy", citing heightened focused and an endless ability to continue lifting. But what exactly is in these pre-work out supplements that are giving off these euphoric feelings? The truth may just surprise you.
It's important to firstly point out that no two pre-work out supplements are exactly the same. Each brand tends to vary the type and dosage of ingredients slightly in an effort to offer an advantage over other similar products. This is a common trend amongst most of the nutritional supplements on the market today. However, despite these variations it is possible to compare each pre work out supplement if you have an understanding of the active ingredients. Table 1.0 details some of the main ingredients within some of the top selling pre work out supplements on the Australian market. However, like any nutritional supplement, it is important you understand and appreciate how the active ingredients work and the legitimacy of the reported benefits. When it comes to supplements, a little bit of research can potentially save you a lot of money and a lot of disappointment. Now for the average gym goer, researching clinical trials and studies on supplements is no easy task. In fact, sadly very few supplement users are actually aware of the physiology behind many of the pills and powders they consume each day. So I've taken the time to help you understand pre work out supplements a little better. I've broken it down into the top 5 selling pre work out supplements and the top 8 ingredients commonly found in these products.
|L-Citrulline / Citrulline Malate||Arginine Nitrate / Alpha-Ketoglutarate||Caffeine Anhydrous||Taurine||Tyrosine||Beta alanine||Glutamine||Creatine|
|Muscle Pharm Assault||?||?||?||?||?||?||?||?|
|Muscle Tech Neuro Core||?||?||?||?|
Table 1.0 - Main ingredients within top selling pre work out supplements on the Australian market
Other names: L-Citrulline, L-Ornithine, N5-aminocarbonyl, N5-aminocarbohyl-orthithin, Alpha-amino-delta-ureidovleric acid
Reported benefits: Increases ATP (energy) synthesis
Increases endogenous Nitric Oxide production
Increases protein synthesis
Increases muscular power output
The Facts: Citrulline is a non-essential amino acid that is a precursor to nitric oxide synthase. Nitric oxide induces vasodilation of the blood vessels, creating increased blood flow into your muscles and produces what is colloquially termed a muscle "pump" effect. Research has shown that 6g/day of citrulline malate consumed orally over 15 days can improve ATP production by 34%.1 Citrulline can delay the onset of fatigue and appears to assist with improved exercise recovery. Citrulline is a fundamental ingredient within most pre workout supplements on the market.
Other Names: L-Arginine, 2-Amino-5-guanidinopentnoic cid, pentaenoic acid, Alpha-ketoglutarate
Reported Benefits: Increases Nitric Oxide production
Increases protein synthesis
The Facts: Arginine is an essential amino acid, synthesized from ornithine and citrulline. It acts as a precursor to creatine phosphate and nitric oxide. Nitric oxide induces vasodilation of the blood vessels, creating increased blood flow into your muscles. Despite the physiological increase in nitric oxide production as a result of oral ingestion of arginine, there is limited evidence to suggest an increase in nitric oxide levels improves exercise performance.2 Therefore, the use of arginine in a pre work out supplement, may not actually be warranted.
Other Names: Caffeine, 1,3,7-trimethylxanthine.
Reported Benefits: Decreases perception of fatigue
Decreases endogenous production of dopamine
Improves mental acuity
The Facts: Low to moderate doses (~3-6mg.kg.BM-1) have been reported to improve sports performance.3 The ergogenic benefits of caffeine come from its ability to stimulate the central nervous system. This causes a delay in the perception of fatigue allowing you to lift more weight, pump out more reps and exercise for longer duration. All 5 of the top selling pre work out supplements contain caffeine anhydrous. So if your pre work out supplement doesn't contain caffeine anhydrous, chances are you've brought the caffeine free version.
Other Names: L-Taurine, Aminoethanesulfonic acid, beta-amino-ethylsufonic acid, 2-aminoethane-sulfonic acid, Ethnesulfonic cid.
Reported Benefits: Increases Energy
Reduces perception of fatigue
Increases protein synthesis
The Facts: Taurine is the most abundant free amino acid in tensile tissue such as the heart, muscles and the brain. When exercising, intramuscular taurine levels gradually deplete with time and particularly when the form of exercise is exhaustive. This is of particular interest as research has shown that an individual's exercise capacity is reduce by a whopping 80% when intramuscular taurine levels are depleted. 4 Similarly, when 500mg per kilogram of body weight is consumed, both intramuscular taurine and exercise capacity increases significantly. 5 Despite the solid evidence behind the use of Taurine, sadly many of the top selling pre work out supplements on the market fail to include it within their ingredients.
Other Names: L-Tyrosine, 4-Hydroxy-L-phenylalanine, L-2-amino-3-p-hydroxyphenylpropanoic acid.
Reported Benefits: Increases Energy
Increases Mental Acuity
Increases Fat Oxidation
Reduces the perception of fatigue
Increase Muscular Power Output
Increases Muscular Strength
The Facts: Tyrosine is an essential amino acid which is a precursor for thyroxine (thyroid hormone) and melanin. However, scientifically speaking, tyrosine won't offer you any improvements in exercise capacity or increase fat oxidation. A double blinded placebo controlled crossover study by Sutton et al in 2005 showed that tyrosine did not improve muscular endurance, muscular strength nor anaerobic performance.6 Despite it being an ingredient found in three of the top five selling pre workout supplements, tyrosine is not an essential ingredient you should be looking for in a pre work out supplement.
Other Names: ?-alanine, beta-aminopropionic acid, 3-aminopropanoic acid.
Reported Benefits: Increases Muscle Hypertrophy
Increases Muscular Strength
Increases Muscular Power Output
The Facts: Beta alanine is a ?-amino acid. Its use as a sports supplement has been largely supported through science. The magic behind beta-alanine is in its ability to increase carnosine synthesis. Carnosine helps to neutralize the unbound, highly charged hydrogen ions (H+) generated from the breakdown of ATP, within the muscles. This buffering effect within the muscles allows for high intensity muscular contractions to be sustained for longer periods of time. Interestingly, beta alanine and taurine (also a ?-amino acid) directly compete for uptake with taurine uptake often reduced in light of beta alanine uptake.7 Because of the proven benefits, most pre work out supplements contain beta alanine, however if your pre work out supplement is missing this ingredient, then it is definitely time for a change.
Other Names: L-glutamine, Levoglutamide, L-2-aminoglutaramidic acid, pentanoic acid.
Reported Benefits: Increases protein synthesis
Improves exercise recovery
Increases glycogen resynthesis
The Facts: Glutamine is a prevalent plasma amino acid. To date there has been no research to demonstrate an improvement in body composition nor exercise performance through the use of glutamine supplementation. Several studies have investigated the potential benefits of glutamine, only to conclude no significant ergogenic benefits.8,9 If your pre work out supplement contains glutamine, it may just be acting as a cheap filler.
Other Names: Creatine Monohydrate, Creatine Ethyl Ester, Creatine HCL
Reported Benefits: Improves Energy Production
Increases Exercise Performance
Increases Muscle Hypertrophy
Improves Exercise Recovery
The Facts: Creatine is a naturally occurring compound that is mostly stored within muscle as phosphocreatine (PCr). Phosphocreatine provides the muscles with a source of phosphate during energy expenditure. This phosphate source helps to increase energy production. Creatine has a substantial amount of evidence to support its claims and has been shown to increase muscle hypertrophy and improve exercise performance.10 Unlike many of other common pre work out ingredients, Creatine actually provides beneficial nutrients to the working muscle fibres and offers long acting benefits.
Summarising the Comparison between Pre-Workout Ingredients
When it comes to pre workout supplements, there are a lot of options out there. However, the main ingredients commonly found within pre work out supplements tend to be mostly the ones mentioned within this article. Most pre work out supplement contains a blend of many of these ingredients, however no two are the same. The main concern with pre work out supplements is they tend to rely on ingredients that are considered stimulants, as opposed to providing nutrients to your muscles. The goal of any pre work supplement should be to increase energy levels, improve mental acuity, reduce perception of fatigue and enhance overall exercise performance. Although all pre work out supplements will claim to offer all of these benefits, far and few actually have ingredients that offer all of these benefits. Using the information and facts highlighted above, you should be able to find the right pre work out supplement for your goals and hopefully one that contains the best ingredients backed by research. Personally speaking I would choose one that contains at a minimum these four ingredients:
- Caffeine Anhydrous
- Beta Alanine
The right pre work out supplement can offer significant benefits in your strength, endurance, mental acuity and give you that muscle "pump", however choosing the right one can be half the struggle.
1) Bendahan D, et.al. Citrulline/malate promotes aerobic energy production in human exercising muscle. Br J Sports Med 2002;36:282-289.
2) Bescós R, Sureda A, Tur JA, Pons A. The effect of nitric-oxide related supplements on human performance. Sports Med. 2012;42:99-117.
3) Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Med. 2001;31(11):785-807.
4) Wrskulat U, et al. Taurine transporter knockout depletes muscle taurine levels and results in severe skeletal muscle impairment but leaves cardiac function uncompromised. FASEB J/ 2004;18(3):577-579.
5) Yatabe Y, et al. Effects of taurine administration in rat skeletal muscles on exercise. J Orthop Sci. 2003;8(3):415-419.
6) Sutton, et al. Ingestion of tyrosine: effects on endurance, muscle strength, and anaerobic performance. Int J Sport Nutr Exerc Metab. 2005;15:173-185.
7) Mori M, et al. ?-alanine and taurine as endogenous agonists at glycine receptors in rate hippocampus in vitro. J Physiol 2002;539(1):191-200.
8 ) Candow DG, et al. Effect of glutamine supplementation combined with resistance training in young adults. Eur J Appl Physiol. 2001;86(2):142-149.
9) Antonio J, et al. The effects of high-dose glutamine ingestion on weightlifting performance. J Strength Cond Res. 2002;16(1):157-160.
10) Volek JS, Kraemer WJ, Bush JA, Boetes M, Incledon T, Clark KL, Lynch JM. Creatine supplementation enhances muscular performance during high-intensity resistance exercise. J Am Diet Assoc. 1997;97(7):765-770.