The Complete Guide to Pre-Workout Supplements

Whether you're a pre-workout novice or a jolt juice expert, here's everything you should know about pre-workout supplements.

Taking a scoop of pre-workout to get fired up has become a regular part of many gym-goers’ daily routine. And just like your heart rate after taking some of the stuff, its popularity shows no signs of slowing down.

In the United States alone, the demand for pre-workout supplements is expected to grow by more than eight percent annually through 2027. Market forecasts also predict high demand in China due to a growing number of gyms opening there. 

But are these caffeine-loaded supplements better than a cup of coffee, or are they just a rip-off? And how do they work? Are they safe for the general population? We’re here to answer all your questions and then some. 

Consider this your ultimate guide to pre-workouts. After reading this piece, you should better understand what’s in them, how often you should be taking them, the potential dangers, and more. 

Editor’s note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. It’s always a good idea to talk to your doctor before beginning a new fitness, nutritional, and/or supplement routine. None of these supplements are meant to treat or cure any disease. If you feel you may be deficient in a particular nutrient or nutrients, please seek a medical professional.

What Are Pre-Workout Supplements?

As its name suggests, you take pre-workout supplements before hitting the gym to boost your performance — especially when it comes to your energy levels. Pre-workouts typically have lots of caffeine to help you work out for longer periods of time. But in actuality, there’s a lot more to these supplements than caffeine. 

[Related: A Powerlifter’s Take on the If It Fits Your Macros (IIFYM) Diet]

Sure, the primary reason many people take them is to feel less zombie-like, but pre-workouts can deliver a lot more benefits such as a better pump, increased strength, and, in some cases, improved hormonal output. This is accomplished through the many ingredients added to the supplement (more on those below). 

While most pre-workout comes in powdered form and are mixed with water — unless you’re one of those dry-scoopers — it can also come in capsules, gummies, and many other varieties. And it’s not just the delivery method that varies, but the ingredients as well. Some pre-workouts are free of caffeine. Others contain nearly the daily recommended dose of the stimulant.

In fact, one 2019 study found that half of the ingredients in the top 100 commercially available pre-workouts were part of a “proprietary blend,” which means the companies don’t disclose how much of a certain compound they put into the stuff. (1) So if you find a pre-workout with its ingredients clearly listed, you’ll next want to make sure it has enough of each.

But what are the vital ingredients, and how much of each should a pre-workout have? Let’s discuss that.

What Should You Look for in a Pre-Workout? 

Like other supplements, you’ll want to ensure that the pre-workout supplement you take is formulated toward your specific needs and preferences. That said, there are five main ingredients you should look for: caffeine, beta-alanine, branched-chain amino acids, creatine, and nitrates

Each of these ingredients plays an important role in preparing you for your workout — at least one is either giving you energy, increasing your strength, improving blood flow, or facilitating another reaction that will help make you stronger or help you to build more muscle mass

In this section, we’ll go over the benefits of the five most common pre-workout ingredients and how much your pre-workout should ideally have. 

Of course, some pre-workouts may have some uncommon ingredients — such as deer antler velvet and Lion’s Mane, and while some of these do have actual health benefits, we’re going to stick with the five main ones for now.

Woman drinking pre-workout
Sergey Peterman/Shutterstock

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While not every pre-workout supplement contains caffeine, this is what most people look for to help give them that extra jolt before entering the iron paradise. And it’s probably the one ingredient here you’re most familiar with. 

Caffeine is a stimulant — that is, it speeds up your central nervous system. You’ve probably also heard at least one person call it a drug, which is correct. Stimulants, whether that be caffeine or nicotine, are considered drugs precisely because of the effect it has on your central nervous system. But don’t worry, you won’t fail a drug test because of pre-workout or a cup of coffee. 

Caffeine, of course, helps keep us alert longer. Most of us have been consuming caffeine since we thought it was a good idea to put that term paper off until the last day, but improved endurance and stamina isn’t the only thing it’s good for. 

Studies have shown caffeine can increase mental clarity, lower pain perception, and improve blood flow to all parts of the body — which are all factors that are vital for athletes. There’s also some proof it may assist in the brain’s activation of muscle contractions. (2)

One potentially negative impact is that caffeine has been shown to increase the “stress” hormone cortisol, impacting your immune system and your body’s natural anabolic processes (such as rebuilding broken down muscle). It does also boost your testosterone levels, but only minimally. (3)

These benefits have been backed up by volumes of scientific research that have endorsed athletes’ use of caffeine for training and competition. For strength athletes specifically, there’s proof that caffeine can help improve peak power compared to a placebo. (4)(5)

As we mentioned before, the caffeine content varies greatly between pre-workouts. If you’re someone who doesn’t need or want that energy boost feel free to look for a caffeine-free pre-workout. These are sometimes called “stim-free,” or stimulant-free, pre-workouts. These are especially good if you work out at night and don’t want to be up until the early morning hours. So what about the people who want caffeine? 

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The benefits we discussed seem to require around 200 milligrams of caffeine, which aligns with the International Society of Sports Nutrition’s stance on caffeine intake for athletes. But there are a few things to keep in mind with that. (6)

First and foremost, you’ll want to keep an eye out for any side effects. Caffeine is a stimulant, and taking too much can lead to health complications, including increased heart rate, muscle tremors, and irritability. If you notice any of these, consider lowering your dosage or taking a break.

Secondly, you want to take into consideration other caffeine sources. The Mayo Clinic says 400 milligrams of caffeine is the daily limit for most healthy adults. This equates to roughly four standard-sized cups of coffee. So if you take a pre-workout with 400mgs of caffeine, skip the cup of Joe for the rest of the day. 


Beta-alanine is a non-essential amino acid, or an amino acid made in sufficient quantities naturally by the body and, therefore, doesn’t need to be obtained through your diet, unlike essential amino acids. But there are many reasons why athletes may want an extra kick of beta-alanine in their systems. 

For one, it’s proven to delay muscle fatigue and prevent lactic acid buildup. So beta-alanine can help you pump out a few more reps at the gym, which leads to additional gains. (7)  Most pre-workouts will typically have around two grams of beta-alanine in them, but for the full effects, you should aim for around four to six grams daily. (8)

Oh, one more note: If you’ve ever taken a pre-workout and felt itchy afterward, you have beta-alanine to thank — this amino acid is what causes that reaction. Don’t worry. It should go away pretty quickly. 

Branched-chain Amino Acids 

Branched-chain amino acids, or BCAAs, consist of three amino acids (valine, leucine, and isoleucine) with different chemical structures. (They’re shaped like branches.) These three amino acids are essential for muscle growth and are often sold on their own in powder form.

Some people take BCAAs independently as a form of pre-workout because they’ve been shown to ward off muscle fatigue and increase energy. There’s conflicting evidence on whether using BCAAs on their own can increase muscle growth, with one saying a proper diet is better than supplements. (9)

Other studies show BCAAs can help improve things like your immune system, but there’s no need for supplementation if you’re getting enough through your diet. (10) Eggs, turkey, quinoa, fish, red meat, cottage cheese, and legume are foods high in amino acids. Short of having your blood drawn and tested, there isn’t a practical way to know if you have “enough” BCAAs. So, if you’re looking to reap their benefits, taking a supplement that contains BCAAs is a fine option.

It’s hard to tell how much BCAAs should be in your pre-workout because the studies done on them focus on the daily requirement for athletes. To that end, most athletes will need anywhere from 10-20 grams per day to get the full effect. (11)


Creatine is created naturally by the body but is also one of many gym-goers favorite supplements. Creatine helps your body create adenosine triphosphate, or energy, to help you perform better and improve muscle contractions. It also helps increase lean muscle mass, and optimize muscle recovery following an intense workout session

Its effectiveness is endorsed by bodybuilders, athletes, and the International Society of Sports Nutrition.

“Creatine monohydrate is the most effective ergogenic nutritional supplement currently available to athletes with the intent of increasing high-intensity exercise capacity and lean body mass during training,” the organization wrote in its official journal. (12)

The same study also said three to five grams of creatine was the optimal dose to have the best effect on your muscle, so you should try to look for something in that range if your pre-workout comes with it. Some don’t have creatine, though, so you’ll have to get it from another source if that’s the case. 


Nitrates are compounds with nitrogen and oxygen molecules that are often found in green, leafy vegetables. There are also synthetic versions created in labs. What do they have to do with pre-workout? Nitrates help create nitric oxide, which is used to relax blood vessels to improve blood flow. Better blood flow means better breathing, lower heart rate, and better muscle contractions. (13)

Most pre-workouts will use L-citrulline or L-arginine, two different amino acids, to boost nitric oxide production, but some also use beetroot juice, rich in nitrates. For this reason, many swear by drinking some beetroot juice before working out — some supplement stores even sell beetroot juice powder. (Comedian and actor Kumail Nanjiani, who transformed his physique, drinks beet juice before a workout.)

Most research says you should keep your nitrate intake to about 10 grams per day, regardless of where you get it from. That’s the number where you get the most benefits, and any more of that is essentially useless because it doesn’t bring on any extra benefits. (14

Are Pre-Workouts Worth the Money? 

Most research studies seem to prove that pre-workouts are indeed a legitimate way to improve your performance, but, like any supplement, they’re not an end-all-be-all solution. One 2016 study, for example, found pre-workouts improved anaerobic power (or the body’s ability to produce energy) but didn’t lead to significant strength increases. (15)

[Related: The Benefits and Uses of Different Types of Creatine]

A wide-ranging review of pre-workout studies says pretty much the same and points out that specific products should be used under the discretion of a sports nutrition expert. The researchers also noted no study has looked at the long-term health effects of pre-workout supplementation (most studies were capped at 12 weeks). (16)

At the end of the day, pre-workout supplements may be a good way for you to eke out a few more reps and feel a little more energized while under heavy iron. But as with anything else, you should track how it affects your body and do your research before dropping a few bucks at the supplement store. 

When Should You Take Pre-Workout? 

Supplement manufacturers will usually suggest you take pre-workout anywhere from 20-30 minutes before the beginning of your workout. This timeframe aligns with what many researchers have done on their subjects, but of course, you might be different. Our bodies metabolize things like caffeine at different rates, so find a timeframe that works best for you. (17)

A Warning Against Dry Scooping

Dry scooping, or taking your pre-workout without water, has been around for years, but the trend has become viral on the video-sharing platform TikTok recently. People believe that this method helps maximize the effects of the supplement because you’re not diluting it. This logic is false and incredibly dangerous. One 20-year-old woman had a heart attack after dry scooping her pre-workout.

Here’s the problem with dry scooping: When you dilute it with water, it gives your body a chance to absorb the ingredients — specifically caffeine — in a responsible manner. If you dump the whole load into your mouth, all that caffeine is going to be absorbed almost instantaneously, and that’s when problems will begin to arise. Also, do not take more than the recommended dose. Caffeine in large doses can be dangerous and even fatal.

You also risk choking on the powder — think of it as a much more dangerous cinnamon challenge. Please, mix the pre-workout with water. 


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