There’s a good reason why pre-workout supplements are a staple in many a weight room regular’s gym bag. The liquid boost pre-workouts offer helps athletes go all-in on their workouts, lifting more, running faster…you get the picture. And with a whole slew of different formulas out there, there’s no doubt you can find a pre-workout that perfectly matches your specific goals (and taste buds). But what are the non-negotiable ingredients every pre-workout should contain? Here’s a look at the anatomy of a truly top-notch pre-workout, plus the perks of those tried-and-true ingredients you’ll see listed on label after label.
The big one: Caffeine
For many people, the term “pre-workout” is synonymous with “caffeine.” The same natural compound people chug coffee and energy drinks for, caffeine helps you feel alert and energized by blocking receptors in the brain for adenosine, which promotes relaxation, according to Dr. Jacob Wilson, Ph.D., C.S.C.S., CEO of the Applied Science and Performance Institute and member of The Vitamin Shoppe Wellness Council. It also bumps up the hormone we know as adrenaline, which boosts heart rate and metabolism, has a pain tolerance-boosting effect, and even helps the heart pump more blood.
With all of its superpowers, even if you were to skip the rest of the ingredients on this list, taking caffeine alone would be a game-changer for your workouts. It’s been shown to improve muscle power, strength, and performance, and to delay the onset of fatigue, shares registered dietitian Brittany Michels, M.S., R.D.N., L.D.N., C.P.T., a nutritionist for The Vitamin Shoppe.
There’s plenty of research out there to back this up, too. Take one large-scale 2021 review published in the Journal of the International Society of Sports Nutrition, for example. In this sweeping overview of caffeine’s impact on exercise, the authors note a number of highlights that include:
- notable benefits in both aerobic and anaerobic exercise, specifically muscular endurance, muscular strength, sprinting, and more
- performance-related perks for both newbie and seasoned exercisers alike
- improvements in cognitive function, including focus
In fact, the research specifically calls out that caffeine-containing pre-workout supplements have been linked to performance benefits in cardio and strength training alike.
You’ll find that pre-workouts contain varying amounts of caffeine—anywhere from a modest 100 milligrams to a hardcore 300 or more milligrams per serving, depending on the formula. Bonus: Some pre-workouts pair caffeine with the amino acid l-theanine for an extra benefit of concentration and focus (look for 100 to 200 milligrams, Wilson recommends).
Another performance must-have: beta-alanine
A modified form of the amino acid alanine, beta-alanine is another household name in the pre-workout world because of its role in boosting muscle endurance, says Michels. Beta-alanine does this by helping prevent the build-up of acid in your muscles (which happens when you train hard) so that you can keep grinding.
Though beta-alanine’s true benefits kick in when you’re taking it consistently (think two weeks or more), according to Wilson, you’ll likely feel its immediate impact every time you down a supplement containing this compound. Yep, beta-alanine is the ingredient behind the tingling sensation a lot of exercisers experience when training after guzzling pre-workout. (Don’t worry; it’s harmless!) That said, research generally suggests it takes around four weeks of supplementing with beta-alanine for its benefits to reach maximum effect.
The amount of beta-alanine you’ll down in a serving of pre-workout varies from formula to formula, typically landing somewhere between one and four grams (though some hardcore products might contain up to six grams), per Wilson. Research suggests that between four and six grams total per day offers the most significant exercise performance perks, particularly when it comes to muscular endurance.
For all the pumps: L-Citrulline and L-Arginine
Sure, round after round of biceps curls is bound to leave your muscles looking bigger and fuller—but taking a pre-workout that contains either l-citrulline or l-arginine (or both!) is a game-changer for maximizing that pump.
Here’s the deal: These two amino acids are famous for boosting nitric oxide (NO) in the body, which “supports the relaxation of blood vessels, improves blood flow, and boosts oxygen and nutrient transport,” explains Michels. This is good news for your workout performance, as research shows these NO-boosters increase blood volume in the muscles, which means more available oxygen and other nutrients to power every rep. (Increased blood volume also means your muscles will look more pumped up.)
Read More: How To Fuel An Intense Workout Without Loads Of Caffeine
These amino acids keep supporting your body post-workout, too. Not only do they support nutrient delivery to your hard-worked muscles (a good thing for the recovery process), but emerging studies suggest they also enhance muscle protein synthesis, the process through which your muscle fibers repair and grow.
Not all pre-workouts contain both of these major players, so take a peek at the label to be sure. L-citrulline is a favorite these days, with many formulas including anywhere from 500 to a whopping 6,000 milligrams. Often, you’ll find higher amounts of l-citrulline in “non-stim” or “stim-free” pre-workout formulas, which don’t contain caffeine or other stimulants, Michels notes. In these cases, formulas may list both l-citrulline and l-arginine. When consumed at a one-to-one ratio in amounts between two and six total grams, the two work together to really ramp up nitric oxide production and blood flow, according to Wilson.
The gains-maker: Creatine
Creatine is a beloved sports nutrition supplement with an empire of research (we’re talking hundreds of studies) behind its ability to support its benefits for muscle-building, exercise performance, recovery, and more. The compound, which is made from the amino acids methionine, glycine, and arginine, “aids in increasing muscle performance by promoting a faster regeneration of ATP, a.k.a. chemical energy, within our cells and muscles between bouts of lifting or high-intensity exercise,” explains Michels. In simple terms: By boosting energy available for muscles to use for quick, intense efforts (think sprints and big lifts), creatine takes performance to the next level.
Time and time again, studies show that, by ramping up performance, creatine helps exercisers increase muscle strength and build muscle mass. More recently, research has also begun to shed light on creatine’s other powers, which include supporting cognition and brain health, bone health, (particularly when combined with resistance training), and even blood sugar regulation.
Typically, pre-workout formulas may contain anywhere from two to five grams of creatine, with creatine monohydrate being the most popular (and most studied) form, Wilson says.
Since creatine is best taken before or after workouts, Michels often recommends athletes consider adding extra creatine to their shaker cup or sports stack, depending on how much their pre-workout formula contains. To reap its power-pumping, muscle-building benefits, 0.03 to 0.06 grams of creatine per kilogram of body weight per day tends to be the sweet spot.
For long-lasting fitness: Betaine anhydrous
A natural compound found in foods like beets and spinach (as well as in the body), betaine anhydrous has been shown to increase work capacity by promoting muscle strength and power, as well as leveling up endurance and sports performance, according to Michels. As such, research—including one 2019 systematic review—also suggests it can positively impact body composition.
Another key—albeit less sexy—benefit of betaine is that it can help decrease homocysteine levels. Why this matters? Elevated homocysteine levels negatively impact the interior lining of blood vessels, and stress—especially stress from intense exercise—can increase homocysteine levels, Michels explains. That means betaine is good news for anyone who wants their workout routine to last for the long (like really long) run.
Read More: 7 Supplements That Support Healthy Blood Pressure
Pre-workout formulas incorporate anywhere between 500 and 2,500 milligrams of betaine anhydrous per serving—and it’s another ingredient you can buy as a stand-alone and add to your stack if you really want to ramp up your intake.
Bonuses: B Vitamins and BCAAs
Beyond the all-star ingredients above, other add-ins you’ll find in pre-workouts really can run the gamut. Some go all-in on energizing herbs like rhodiola and ginseng, while others include balancing adaptogens like ashwagandha. That said, there are two other popular boosts you’ll see on many an ingredient list: B vitamins and BCAAs.
The B vitamins (B6, B12, and folic acid are some of the most included) are an energy play, as many in this group of nutrients play important roles in metabolism and energy production. While folic acid helps cells divide and supports DNA production, B6 helps fuel the metabolism, and B12 breaks down fatty acids.
In many cases, you’ll find pretty high amounts of these B vitamins—like, more than 100 percent of your daily needs—in a serving of pre-workout. Formulas may contain extra high amounts of B12, in particular. Don’t sweat, though; you’ll pee out what your body doesn’t need.
BCAAs, meanwhile, are more about promoting recovery, though they can also help reduce fatigue, Wilson notes. These aminos—leucine, isoleucine, and valine—have been shown to play critical roles in muscle performance and recovery. Leucine, in particular, has long been known to support muscle protein synthesis, the process through which the body builds muscle. That’s pretty important after tough training sessions, which actually cause micro-traumas within muscle tissue. In addition to that, though, the BCAAs can be used (albeit in small amounts) to produce the energy muscles need to keep on working.
Pre-workout supplements may include anywhere between one and five grams of BCAAs, Wilson says.
Your Perfect Pre-Workout
Since there are so many different pre-workout formulas out there, don’t be afraid to test a few options in an effort to figure out which best fits your workout routine and fitness goals. While the ingredients above are certainly some of the most popular, every formula is unique!
Not sure if your current formula is really working for you? Here are five signs it’s time to try a new pre-workout. Some of our current favorites: Gorilla Mind Gorilla Mode White Gummy Bear Pre-Workout Formula and BodyTech Elite Rocket Pop Altered Strength Pre-Workout.