There is a vast array of pre-workout products out there, containing a wide variety of ingredients some of which in my opinion are legitimate and others not so. Pre-workout products are designed to boost your performance in the gym and are sworn by, by many who claim they can’t train as well without them. Their main claims are to increase focus, boost energy, create better muscle pumps and improve nutrient delivery.
So let’s look at the main ingredients that are common in pre-workouts.
Caffeine is the most commonly used stimulant. I discussed it when I looked at its fat burning qualities, but caffeine’s ability to stimulate the central nervous system (CNS), raise alertness and focus , reduce the perceived rate of exertion and boost short term performance is well documented. However, I also mentioned how you have to use caffeine judiciously as it is easy to build up a tolerance to it.
As with most drugs some people are more sensitive and responsive. We all process caffeine differently (some not very well) and have different tolerance levels, so it may not work as well for some people. Dosage is also important as taking too much can overstimulate the CNS and this can actually impair performance.
There are a number of other substances that can be included in pre-workouts, like guarana, ginseng and yohimbine that provide similar effects to caffeine.
Ephedrine has been used in the past in pre-workouts as is it is a powerful stimulant, working in a similar manner to amphetamines. However, it can have serious side effects and is rarely found in supplements or so many medications now.
Dimethylamylamine (DMAA) is another powerful stimulant that was used in a number of supplements like Jack 3D, until its use was recently banned, after it was linked to a number of deaths.
L-Tyrosine is an amino acid that can have a stimulant effect, when used in conjunction with other stimulants. There is not a lot of great evidence to support its use.
Personally I’m not keen on the use of stimulants. This is not a moral question for me. Firstly, it concerns me that people need stimulants to get a good workout, and secondly, I have found the use of stimulants impairs my performance in the gym and a low dose adds nothing.
Long term stimulant use also has dangers and can lead to adrenal fatigue, where your adrenal glands almost shut down due to being overworked.
Muscle building substances
Creatine I discussed under muscle building substances. I discussed that it has been shown to be an effective ingredient and is worth adding to your diet if building muscle is your goal.
Beta-alanine is another I discussed before, and again has evidence to suggest it might be a worthwhile ingredient.
L-arginine is often added to boost nitric oxide levels. Nitric oxide is claimed to increase the release of hormones and adrenaline, boost muscle pump, and speed growth and recovery time mainly through improved circulation. The evidence for L-arginine is poor as a booster of nitric oxide, and as I discussed under muscle building supplements food containing high levels of nitrate, like beetroot are far more effective.
Branch-chain amino acids (BCAA) are commonly added. BCAA’s are the amino acids leucine, valine and iso-leucine. These amino acids, especially leucine are important in the process of muscle protein synthesis. However, if you are getting enough in your diet (and especially if you are consuming whey protein, which is relatively high in BCAA’s) the evidence for including these pre-workout is not that strong.
Substances designed to prolong exercise
L-Citrulline (usually in the form of citrulline malate) is an amino acid that is converted into L-arginine in the liver. Supplementing with citrulline malate is actually more effective at increasing L-arginine levels than supplementing with L-arginine itself. L-citrulline has beeen shown to reduce fatigue and improve endurance in both aerobic and anaerobic activities.
Beta-alanine and nitrate I covered above, but their muscle building qualities (as with citrulline malate) come from their ability to delay fatigue.
Taurine is also commonly used in sports drinks and pre-workouts. It is an organic acid, similar in structure to amino acids. It was often used in supplements containing ephedrine, in order to reduce any cramping caused as a side effect of ephedrine. It promotes good health in the heart and blood and is found in many foods, especially meat. There is no solid evidence for supplementing with taurine for exercise though.
The final substance I want to cover is HMB (β-Hydroxy β-Methylbutyrate). HMB is a metabolite of the amino acid leucine and approximately 5% of the leucine you consume is oxidised into HMB. It reduces the rate of muscle protein breakdown and is sold on that basis. While it is an interesting supplement and may help prevent muscle wastage in conditions that promote that, there are no studies however, that have shown significant results for the use of HMB in exercise populations.
One final issue when you buy supplements that are stacks, is do all the substances actually work, do they work together and/or are they in the right dosage? Most people will have difficulty in determining that.
That’s why I recommend targeting your supplementation. Pick supplements that (1) there is evidence for, (2) that will benefit your training and (3) take them at the recommended doses.