What Are Pre-Workout Supplements—And Do You Need Them?


You can find a supplement claiming to help boost pretty much anything: sleep, immunity, joint pain, relaxation, gut health, post-workout recovery. Lately, though, it’s the pre-workout supplements category that’s been getting a lot of attention. (Not all of it good.)

Scrolling through Instagram, you might get the idea that pre-workout supplements—known colloquially as a “pre-workout”—are a fitness staple that’s seemingly just as necessary as a proper-fitting sports bra and a pair of sneakers.

In fact, there are over 4.6 million posts on Instagram with the hashtag “preworkout,” and the photos show you just how varied that term can be: There are chews, capsules, canned drinks, powders, and colorful liquid in shaker bottles all promising to help you get in a better workout.

It used to be that you ate a banana or piece of toast before a tough workout, and that was sufficient. But now, it seems like every exerciser (at least on social media) is talking about pre-workout.

“If I want to get in a good workout, I need pre-workout.” “Oh my God! This workout is so hard. I can’t believe I forgot to take my pre-workout!” “Seriously, you don’t take pre-workout?”

Given how often people talk about these supplements and how heavily marketed they’ve become, it’s worth knowing what scientific research and experts in this area have to say about it. Turns out, while some pre-workouts may contain safe, energy-boosting ingredients, others can be pointless—or potentially harmful. Here’s what you need to know before joining the pre-workout faithfuls.

What is pre-workout?

“Pre-workout” is any supplement—usually a powder drink mix, but also available in the forms listed above—that claims to boost workout performance if you consume it beforehand.

First of all, it’s important to realize that virtually every supplement and exercise nutrition brand out there has its own pre-workout formula, meaning that no two tubs contain the same—or even similar—ingredients. In fact, according to a 2019 study of the top 100 commercially available pre-workout supplements, nearly half of all ingredients were part of a “proprietary blend,” meaning the amounts of each ingredient were not disclosed.

“There’s really no good definition of what a pre-workout supplement is—and a lot of companies are just slapping it on products because it’s ‘in’ right now—but in general, it’s a product that’s intended to boost energy levels, generally though a combination of B vitamins, carbs, and antioxidants,” registered dietitian Jessica Crandall, R.D.N., C.D.E., a spokesperson for the Academy of Nutrition and Dietetics, tells SELF.

Why do people take pre-workout?

Most people take pre-workout to rev themselves up so they can exercise harder, or to simply feel better and less zonked when working out. The hope is that the pre-workout will “help enhance performance, mainly through the boosting of energy and increased mental focus,” Yasi Ansari, M.S., R.D., C.S.S.D., a Los-Angeles-based registered dietitian nutritionist, certified specialist in sports dietetics, and National Media Spokesperson for the Academy of Nutrition and Dietetics, tells SELF.

Pre-workout supplements have been studied on a bunch of workout metrics, including strength, power, and endurance, as well as time it takes to fatigue, and perception of effort—or how hard it feels like you’re working during a given task.

For those reasons, people may choose to take pre-workout before a variety of workouts, from trying to increase their 1-rep max on the back squat, power through an interval-heavy running workout, or simply have enough gas left in the tank to crank out the final burpee in a HIIT class.