Pre-workout supplements make big promises to boost your performance, and with those promises come high price tags. You supposedly get a burst of energy, fatigue less easily and increase blood flow, all to help you get more out of your workout. The thing is, these supplements are really just powerful stimulants. Illustration by: Sam Woolley.
Pre-workout supplements are pretty popular, and you can find them from pretty much any company that also sells protein powders. Optimum Nutrition, MusclePharm and Cellucor are just a few of the major players. They typically come in powdered form, are meant to be mixed with water and taste like a flavoured sports drink — which makes sense because they're loaded with artificial sweeteners, colouring agents and other ingredients that we'll get to shortly.
Within 20-30 minutes of drinking one, you start to feel something, like it's "kicked in" and you're ready for your workout. It's a blessing, but also a curse.
It's Mostly the Caffeine That "Works"
Most pre-workout supplements contain caffeine. And lots of it.
Caffeine is commonly used by athletes, especially those in endurance sports, to improve their exercise performance. It helps you focus more and feel less fatigue — exactly the claims the supplement labels make! So, in reality, when you feel like you're ready to take on the entire weight room, you can thank the caffeine for that, not the supplement.
The pre-workouts I've tried from Optimum Nutrition, JYM and Kaged Muscle contain between 175mg (Optimum Nutrition) and 300mg of caffeine per serving (Kaged Muscle). For real-world context, a single can of Red Bull has 80mg of caffeine and a cup of coffee is close to 100mg.
While some of the research shows promising lifting benefits with high doses of caffeine (like this study in Medicine and Science in Sports and Exercise), the caffeine dose is typically tailored to the individual — about six to nine milligrams of caffeine per kilogram of bodyweight. That's 409-612mg for a 68kg person, for example.
Unfortunately, these supplements too often provide an enormous hit of caffeine, without letting you dose an appropriate amount for yourself. Plus, you get a bunch of other fluff. If you're looking for that extra performance edge from caffeine, you're better off getting it from other sources, like coffee or caffeine pills, where you can control the dosage yourself.
The Useful Ingredients Aren't Always in Effective Doses
At their core, all pre-workout supplement formulas are similar. They contain a blend of science-sounding compounds that claim to increase blood flow to muscles, boost energy production and more quickly clear out metabolites that would otherwise fatigue your muscles faster.
Typically, you'll find creatine, arginine, beta-alanine, carnitine and citrulline, to name a few. All of these are also found in the body, and supplementation with a few of them actually do have proven benefits — in the proper doses and with consistent intake. Here are a few well-researched ingredients with notable benefits, and ones you should look out for when considering a supplement:
Standard Effective Dose: 5g
Creatine is stored in your muscles and used as an extra energy source when you work them. During bursts of intense activity like weightlifting, you quickly deplete a form of energy called ATP. When you supplement with creatine, you increase the available creatine in your muscles so that it can regenerate ATP stores faster and help you work out harder.
The International Society of Sports Nutrition wrote in a position paper that creatine is a safe, effective and ethical way for an athlete to improve strength and power and gain more muscle. A review of over 80 studies on creatine in Journal of the International Society of Sports Nutrition also noted clear strength benefits for weightlifters, as well as positive effects on muscle building.
Two things to note: There are different forms of creatine, but creatine monohydrate is the most well-studied; and the benefits of creatine don't happen immediately. It takes time for your muscles to be "loaded" with creatine, though you can get benefits faster by taking higher amounts. For more details on that, check out this article on Examine.com.
Standard Effective Dose: 2.4g
Most studies on beta-alanine, such as this one International Journal of Sports Medicine, show that it helps people squeeze out a few more reps when training in the higher rep range (like between eight and 15 reps). A review of the literature in the journal Amino Acids suggested that beta-alanine improved performance in moderately intense activities that lasted between 60-240 seconds. That means this isn't likely to help with, say, a one-rep max bench press.
The explanation here is that beta-alanine turns into carnosine in the body. As you "feel that burn" from hard exercise, carnosine is released to buffer the increase in lactate (an acid) and help you continue exercising a bit longer.
When you take beta-alanine or any pre-workout supplement containing more than two grams of it, you'll feel a bizarre, tingly sensation, usually in your hands and face. Don't worry, it's a harmless and common effect called paresthesia.
Standard Effective Dose: 0.5g
Nitrates are found in green leafy and tuber vegetables, such as in spinach and beet roots, and in the stuff that's used to cure ham. You typically supplement with beet juice and eating leafy greens, and in pre-workout supplements, the ingredient is beet extract. When you take in nitrates, they get broken down in the body into nitrite and converted into nitric oxide during hard activity where you have a hard time getting enough oxygen.
The more nitrates, the more available nitric oxide there is. This aids exercise since nitric oxide widens blood vessels, increasing blood flow, and seems to help you work harder, longer. One study in the Journal of Applied Physiology found that three days of supplementing with nitrates (through beet juice) reduced the amount of oxygen needed to perform exercise at moderate intensity, in addition to helping subjects last longer during really intense, near-maximal exercise.
Another reason pre-workout supplements love to emphasise nitric oxide is that you tend to feel like your muscles are bigger than they really are (known as "the pump" in fitness circles) from the increased blood flow.
While pre-workout supplements usually include these ingredients (and many others), the actual labels on bottles are often obfuscated by a company's proprietary blend, or a signature "secret" blend that hides the exact amounts of listed ingredients. So it's not uncommon for supplement companies to under-dose on the good stuff, like beta-alanine.
Labdoor, an independent supplement testing lab, took 46 of the most popular pre-workout supplements and analysed the contents to check against the bottles' labels and ingredient claims. They found that only two — Legion Pulse and Optimum Nutrition Platinum Pre-workout — out of 46 actually contained effective doses and were true to their labels (full disclosure, the site makes money through affiliate links). That said, I am not endorsing those two products: having accurate labels is just the ethical thing to do.
This Industry Is Rife With Safety Concerns
In the US, the FDA regulates supplements in general, but their oversight has been lax and often limited by resources. In Australia, supplements are regulated by the Therapeutic Goods Administration, however most are only required to provide proof that they don't contain banned ingredients. Further, these regulations are not heavily policed, so in practice there is very little control or oversight. That alone is a huge safety concern, and as I touched on earlier, you never know exactly what is in the bottle of any supplement you buy. And sometimes that can lead to real harm.
In 2011 and 2012, several cases of pre-workout supplement-related deaths in the US were linked to a product called Jack3d, which at the time still contained a powerful stimulant called 1,3-dimethylamylamine, or DMAA. DMAA is structurally similar to amphetamine, and since early 2000s, has been marketed as a natural weight loss aid.
For a time even after the controversy started, Jack3d continued to be marketed as "safe and effective". It took an additional two years and dozens upon dozens of adverse case reports for Jack3d to be recalled by the FDA and for the supplement manufacturer to agree to stop making it with DMAA. You can still buy Jack3d, but the current formula doesn't include DMAA.
Disappointingly, products with DMAA are still available in the marketplace. While the FDA is doing what it can to remove dietary supplements with DMAA, you can be more vigilant by looking closely at the label. DMAA goes by other names, including geranamine, dimethylamylamine and methylhexanamine. You can find the full list here.
Aside from regulatory concerns, there are potential unpleasant side effects of taking pre-workout supplements. I've experienced some unfortunate gastrointestinal issues when I took Pre-JYM and Cellucor's C4. Friends and former colleagues have told me pre-workout supplements in general give them trouble sleeping at night, concentrating during the day and headaches.
If the whole point is to work out harder and more intensely, you can do the same by taking caffeine by itself. Coffee is my personal go-to (and it's dang tasty). As far as I'm concerned, the only people who possibly need pre-workout supplements are fitness models who lack energy from a long dieting period. If you're after those claims of getting stronger and performing better, try looking into the individual ingredients, such as creatine and beta-alanine, and taking them separately, where you can moderate the dose to your needs and fitness goals.
In general, pre-workout supplements can "work" because they may change the way you feel, mostly thanks to our friend caffeine. The kicker is, neither caffeine nor pre-workout supplements will automatically make anyone stronger, bigger or faster. You still need to be willing to work your arse off when you exercise.