If you’ve trained your social-media algorithms to serve you even a little bit of fitness content, scrolling your TikTok feed might feel like wandering the aisles of a vitamin store. Workout vlogs often feature a prominently displayed tub of something called pre-workout powder: Just mix a scoop into a glass of water, down it before exercising, and you’ll instantly become more efficient and energized during your workout.
That’s the hoped-for benefit, anyway. The reality is more of a gamble.
“Pre-workout,” a packaged powder that contains at least a dozen supplements—and usually more—started as a DIY obsession among bodybuilders and weightlifters in the early 2000s. “There were really only a couple that were on the market at that time,” says Andrew Jagim, director of sports medicine research at the Mayo Clinic Health System who has studied pre-workout supplements. “And then, by 2010, you instantly had probably hundreds of pre-workout supplement brands on the market.”
Now, social-media platforms—mostly TikTok, where fitness “journeys” often include regular updates about what people are consuming—have helped these reach more mainstream audiences and explode in popularity.
The pandemic pushed things along; when COVID-19 shut down gyms and dismantled workout routines, pre-workout powders looked to many like an easy way to stay fit.
What’s in pre-workout?
While protein powders help deliver a dose of just one nutrient during workout recovery, pre-workouts promise a different set of ingredients engineered to be immediately usable during your workout.
Blends generally fall into two categories: “stim” and “non-stim.” Stim, or stimulant pre-workout, contains caffeine, while non-stim options claim to provide alertness and focus via one or more nootropic ingredients like taurine, which haven’t been conclusively shown to provide benefits. Both types of pre-workout often contain a few other staple ingredients, including beta-alanine, an amino acid that helps produce a compound that prevents the feeling of muscle burning (but can cause an itching feeling some users don’t like). Formulas often also include creatine for energy, as well as citrulline, another amino acid that in certain doses may help increase the body’s blood flow.
But even if you actually read the ingredients on the back of a pre-workout container, you might not be any closer to knowing the contents or benefits of the scoop you’re about to take, says Jagim. Studies consistently find that “the actual content of what’s in some of these products doesn’t always match up with what’s on the label,” he says. Dosages—and even ingredients—aren’t always clearly labeled, since supplements like pre-workout aren’t subject to the same strict U.S. Food and Drug Administration regulation as medications.
Manufacturers are able to obscure quantities of and information about key ingredients by categorizing them as part of “proprietary blends.” In a 2019 study looking at the top 100 pre-workout products on the market, Jagim and his colleagues found that of the average 18 ingredients per supplement, roughly eight to 10 were listed as part of these blends, so their quantities weren’t disclosed. Of the ingredients for which quantities were provided, some, such as beta-alanine, tended to be included in such small amounts that they were unlikely to be effective.
Aside from caffeine, many ingredients included in pre-workout don’t even really take effect until they’ve built up to certain levels from repeated doses. In other words, if you’re taking pre-workout once a week before a fitness class, “you’re just paying for really expensive caffeine,” Jagim says.
The health risks of pre-workout
An even bigger risk than wasting money is that the mix you buy may contain stuff that isn’t listed on the label—including illegal substances with documented health risks, like “amphetamine-like compounds and anabolic steroid derivatives,” says Jagim. More than 30 studies from the last two decades have “pulled these products off the shelves, run them through a lab, and looked for these different kinds of illegal substances,” he says. Their findings are often alarming. One 2021 study that analyzed 30 different commercially available sports supplements found that more than one-third contained traces of anabolic steroids. For this reason, the use of products like pre-workouts is often discouraged among college and professional athletes. The FDA has regularly issued warnings about bodybuilding products like pre-workout, and though they’ve sent warning letters to some of the companies found to be using illegal ingredients, the agency is unable to monitor the entire industry.
One of the most common illegal ingredients in pre-workout products is methylhexaneamine, also known as DMAA, an amphetamine derivative similar to the active ingredients found in attention-deficit hyperactivity disorder (ADHD) medications. Though you’re unlikely to pick up a pre-workout that promotes its DMAA content in stores, dozens of brands—most in countries outside of the U.S.—do advertise the inclusion of the chemical and its analogs in their blends, and many are even sold on sites like Amazon. DMAA, which constricts blood vessels, can be dangerous for the heart, lungs, and other organs. These effects can also be exaggerated when combined with other stimulants, such as caffeine, making their presence in unmarked blends even more dangerous.
That’s not to say that there’s no safe way to use pre-workout, says Jagim. A few independent organizations, such as Informed Sport and BSCG, run programs to test and certify the contents of popular supplements on the market. Those ensured to contain only what they say they do have a stamp of approval on the label. If you’re shopping for supplements, says Jagim, always keep an eye out for these third-party verification markers. Equally important is staying within the recommended dosage outlined by the company, since some ingredients that are safe and effective in smaller quantities can be dangerous if you’re doubling or tripling your pre-workout scoop. Caffeine, in particular, can multiply pretty quickly in some of these scoops, says Jagim.
Caffeine is also a major reason why experts don’t recommend that teenagers use pre-workout. “It’s not the healthiest habit for younger athletes to get into,” says Jagim. Most of the individual supplements present in these blends haven’t been tested much in kids or adolescents, and the high amounts of caffeine alone in some mixes can disrupt sleep and more.
Who uses this stuff?
Because companies can’t make unsubstantiated health claims about their products that pertain to disease risk and cures, pre-workout brands instead market these as lifestyle products—invoking aspirational ideas about who you are and what you do. Some popular brands have names like “I AM GOD,” “Superpump Aggression,” and “Harambe Blood”—and that’s because companies know the language of their customers. Gen Z’s growing buying power is setting the wellness trends now, says Angela Espersen, a senior brand strategist at the creative agency Murmur. “They’re much more traditionally fitness-oriented than Millennials,” she says, “and I think we’re seeing a lot of brands starting to shift because they don’t want to miss out on that.”
While Millennials may have scoffed at unabashedly artificial products like these during the more “natural”-oriented health movements of years past, pre-workout’s current popularity reflects changing priorities. “Psychologically, our awareness of our own physical appearance is higher than it ever has been,” Espersen says. “There’s this conspicuous self, and I think that’s why we see these products being used.”
Wellness products also lend themselves to the stunt-based showmanship of social-media, which has led to people using pre-workout in potentially dangerous ways. Videos on TikTok show it going into Jello shots, slushies, and homemade fruit snacks. People double and triple scoop it into water. It coats fruit, gets mixed into alcohol, and even gets snorted. The most popular stunt is dry-scooping, which involves skipping the water altogether for a mouthful of dry powder. (Dry-scooping is likely self-defeating, Jagim says, since several pre-workout ingredients, including creatine, require a fair bit of hydration to work in the body.)
Given how ubiquitous they seem online, it might be easy to feel like you’re not a true fitness buff unless you use pre-workout. But plenty of people—Jagim included—have lifted for years without the stuff. A chug of coffee and your favorite snack will fuel you just fine.
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