Pre-workout has become increasingly popular among athletes and novice fitness enthusiasts alike. The supplement promises to enhance performance, boost energy levels, and maximize workout results. But, it can be difficult to navigate whether or not pre-workout is worth adding to your routine. And, if it is, how do you choose the right one? Understanding how pre-workout supplements work, as well as their claimed benefits and potential side effects, is necessary to help you make an informed choice.
Our team of nutrition and fitness experts breaks down everything you need to know about the best pre-workout supplements : how they work, what’s in them, and how to make the best decision based on your health goals.
Meet the expert
Rob Wildman , Ph.D., ”Dr. Rob,” is a registered dietitian, sports nutritionist, and fitness expert. Having worked for major sports nutrition brands, Dr. Rob is well-versed in all things supplements—including pre-workouts. Dr. Rob sat down with Levi Bettwieser, a member of our editorial team, to share his pre-workout know-how.
Medical disclaimer: This article is intended for educational and informational purposes only. It is not intended as a substitute for medical advice. For health advice, contact a licensed healthcare provider.
What is pre-workout?
Pre-workout supplements are exactly what they sound like: supplements you take before a workout. You can find pre-workouts in a variety of forms: powders, pills, or drinks. The primary purpose of pre-workout is to provide a boost in energy, focus, and endurance to maximize the effectiveness of exercise sessions.
“A pre-workout is a nutrient, or any combination of nutrients, that somebody would take before an exercise session with the goal of really enhancing either the performance, the experience, or the recovery of an exercise session,” explains Dr. Rob.
These supplements often contain a combination of ingredients to target different aspects of performance. Common components include caffeine, which enhances alertness and reduces perceived exertion during exercise, beta-alanine, which can delay muscle fatigue, and creatine, which aids in muscle strength and power output. Other ingredients like BCAAs (branched-chain amino acids), nitric oxide precursors, and vitamins and minerals may also be included to support muscle function and overall health. ( 1 , 2 , 3 )
While many pre-workout supplements may contain many of the same ingredients, it’s important to consider your individual tolerance to certain ingredients like caffeine, which is a common addition. If you notice yourself getting shaky after taking a caffeinated pre-workout, then a non-stim pre-workout option may be a better choice.
Pre-workout supplements can be a valuable tool when used appropriately. ( 4 ) But, taking a pre-workout supplement doesn’t mean you can forget everything else related to your well-being. Maintaining a balanced diet and exercise regimen, and practicing quality sleep habits, are still the best things you can do for your health. Pre-workout supplements should be an addition to proper diet, exercise, and sleep—not a replacement for healthy habits.
Benefits of pre-workout
The potential benefits of a pre-workout will ultimately depend on the ingredients and formulation of the supplement you choose.
“Oftentimes, the user is looking for more sharpness, more focus, more concentration, or a higher level of vitality and energy so that they can better enjoy and have a more focused workout session,” says Dr. Rob. “So you see nutrients that are aligned specifically for that purpose and then the claims that go with them. Also, there are nutrients that are going to support strength, either immediate strength or strength when they’re taken over time.”
Dr. Rob explained that pre-workout ingredients like beta-alanine, betaine, and creatine are more of a long-term investment. You might not see an immediate effect in your first few workouts, but after a few weeks of consistent use, the benefits will become more obvious.
Increased energy and reduced fatigue
Pre-workout supplements often contain stimulants like caffeine, providing a quick energy boost that can help combat fatigue during workouts. This increased energy can lead to improved performance and endurance, allowing individuals to push through more challenging workouts. ( 1 )
If you want a bigger energy boost from your pre-workout, a stronger pre-workout (a pre-workout that contains more caffeine) may be helpful.
Enhanced focus and concentration
Ingredients such as caffeine, certain amino acids, and nootropics in pre-workout supplements may help improve mental focus and concentration. This can benefit your workout by helping you stay more engaged and focused on the movements you’re doing, leading to more productive training sessions. ( 1 )
Improved endurance and performance
Another common pre-workout ingredient, beta-alanine, has been shown to delay muscle fatigue by buffering lactic acid buildup. This delay in fatigue can extend exercise duration and intensity, ultimately improving overall endurance and performance. You likely won’t see this shift overnight—you’ll need to regularly take a beta-alanine product for a few weeks to notice the performance-enhancing effects. ( 2 )
Increased strength and power output
Many pre-workout supplements contain creatine, a compound known for its ability to increase muscle strength and power output. Creatine enhances ATP production, which can result in improved performance, particularly in activities requiring strength and explosive movements. ( 3 )
Enhanced blood flow and muscle pumps
Some pre-workout ingredients, like citrulline, are nitric oxide boosters. They promote vasodilation, leading to increased blood flow to the muscles. This improved circulation can enhance muscle pumps, facilitate better nutrient delivery, and optimize muscle performance during exercise. ( 5 )
Accelerated recovery
Certain pre-workout ingredients, such as BCAAs, may aid in reducing muscle soreness and promoting faster recovery post-workout. By supporting muscle repair and protein synthesis, these supplements can help individuals recover more quickly from intense training sessions. ( 6 )
Does pre-workout work?
The effectiveness of pre-workout supplements largely depends on individual factors such as body composition, metabolism, tolerance to ingredients, and specific fitness goals. For many individuals, pre-workout supplements can enhance exercise performance and provide noticeable benefits during workouts. ( 4 )
But caffeine—and its corresponding effect on energy—is what a majority of people will notice most from their pre-workout.
“Caffeine is the king of the pre-workout nutrients. You get a nice energy lift when you take caffeine and caffeine-related nutrients before a workout,” says Dr. Rob. “It is scientifically proven that when you deliver key nutrients prior to a workout, the workout tends to be better, and the results can be better. The adaptations in strength and size, performance can be better over time.”
Additionally, ingredients like creatine, beta-alanine, and citrulline found in pre-workout formulations have been extensively studied for their potential to improve strength, power, endurance, and muscle pumps. ( 3 , 2 , 5 )
However, it’s important to note that the efficacy of pre-workout supplements can vary among individuals, and not everyone may experience the same degree of benefits. Furthermore, the quality and specific formulation of pre-workout products can significantly impact their effectiveness.
Before purchasing a pre-workout, it’s worth taking some time to assess exactly what you hope to get out of the supplement. Your needs, preferences, fitness goals, and potential side effects should all play a role in determining which pre-workout supplement you take.
Pre-workout ingredients: what to look for and what to avoid
Carefully reading a pre-workout product’s ingredient label is the best way to assess safety, efficacy, and quality. Here’s what to look for and avoid:
Ingredients to look for
Caffeine
As we’ve already discussed, caffeine is a common ingredient in pre-workout supplements due to its stimulant properties, which can enhance energy, focus, and exercise performance. But for many people, too much caffeine can have negative side effects. Ideally, a pre-workout supplement should contain 150-300 milligrams of caffeine per serving to avoid excessive jitteriness or potential side effects. ( 1 ) To put that into perspective, one cup of traditional drip coffee has around 100 milligrams of caffeine.
Creatine
Creatine is well-known for its ability to increase muscle strength, power output, and muscle mass when used consistently over time. Look for pre-workout supplements containing creatine monohydrate, the most researched and proven form of creatine, at a dosage of around 3-5 grams per serving. ( 3 )
Beta-alanine
Beta-alanine is an amino acid that can help buffer lactic acid buildup in muscles, delaying fatigue and improving endurance during high-intensity exercise. Look for products containing beta-alanine at a dosage of around 4-6 grams per serving for optimal benefits. ( 7 ) Keep in mind that beta-alanine can sometimes cause an alarming, though harmless, tingling sensation, especially if you’ve never used it before.
“Beta-alanine will have that experiential effect, so that you know that you’ve taken a pre-workout because you have this neurological tingling in your periphery, which is referred to as paraesthesia,” explains Dr. Rob. “So this is important for a lot of people because it signals that their pre-workout is in their body and that they’re ready to go, they’re primed up.”
Citrulline malate or L-citrulline
Citrulline malate is a compound that enhances nitric oxide production, which may lead to improved blood flow, muscle pumps, and exercise performance. Look for pre-workout supplements containing citrulline malate at a dosage of around 6-8 grams per serving. ( 8 )
Ingredients to avoid
Avoiding certain ingredients is crucial because they can compromise safety or effectiveness. Not only can this potentially lead to adverse health effects, but for athletes in tested sports, it could result in failed drug tests.
Proprietary blends
Proprietary blends tend to obscure specific dosages of individual ingredients. This makes it challenging to assess the product’s effectiveness or potential side effects it may have. We recommend avoiding these blends when possible.
Artificial sweeteners and colors
Some pre-workout supplements may contain artificial sweeteners and colors, which can be unnecessary additives and may cause digestive discomfort or allergic reactions in some individuals. It’s best to instead opt for products with natural sweeteners and colors.
Excessive caffeine
While caffeine can provide benefits in moderate doses, excessive consumption can lead to side effects like jitteriness, increased heart rate, and insomnia. Avoid pre-workout supplements with excessively high caffeine content, especially if you’re sensitive to stimulants or consume other sources of caffeine throughout the day. ( 1 )
What to look for in a pre-workout
In addition to scrutinizing the ingredients list, there are a few other things to consider when choosing a pre-workout supplement.
Third-party testing and certification
Third-party testing from reputable organizations like NSF, Informed Choice, or Labdoor, helps ensure a pre-workout’s quality. This testing means the product has been independently verified for quality, purity, and accuracy of ingredient labeling, reducing the risk of contamination or undisclosed ingredients.
“You definitely want to make sure that your products are clean and safe,” says Dr. Rob. “These types of [certification] programs are going to take the products and they’re going to analyze them to make sure that there are no illegal or banned substances within that product. Not only is that great assurance for athletes who may get drug tested but also it’s a great assurance for everybody out there to make sure that there’s no cross-contamination, that there’s nothing in the product that’s not on the label.”
Transparent labeling and dosage transparency
Transparent labeling simply means that a product’s nutrition label clearly indicates the exact amount of each ingredient per serving. Knowing the precise dosage of key ingredients like citrulline, caffeine, creatine, and beta-alanine allows you to assess their effectiveness and avoid under-dosed products that may not deliver optimal benefits.
Clinical research and efficacy
The pre-workout supplement you choose to add to your routine should abide by the scientific research and clinical studies that support efficacy and safety. Look for products with ingredients that have demonstrated benefits in peer-reviewed studies for improving exercise performance, endurance, strength, and muscle growth. Just because a pre-workout has a dozen ingredients doesn’t mean it’s a better product than a pre-workout with fewer ingredients.
Reputation and reviews
Before purchasing a supplement, it’s also worth considering the reputation and reviews of the product, both from consumers and nutrition and fitness professionals. Look for testimonials and feedback from individuals who have used the pre-workout in question, paying attention to consumers’ experiences with effectiveness, taste, mixability, and side effects.
Personal considerations and preferences
Lastly, consider the person who matters most when making decisions for your health—you! Your preferences, dietary restrictions, tolerance levels, fitness goals, and lifestyle factors are all important when selecting a pre-workout supplement.
“Be your own scientist, and you’ll learn pretty quickly which nutrients you like, which brands you really trust, and which marks and certifications you want to look for when you’re purchasing your products,” Dr. Rob advises.
What are the side effects of pre-workout?
While pre-workout supplements can provide various benefits for enhancing exercise performance, they may also carry potential side effects, particularly when consumed in excessive amounts or by individuals sensitive to certain ingredients.
Here are some common side effects to watch out for:
Jitters and nervousness
High doses of stimulants like caffeine found in pre-workout supplements can lead to feelings of jitteriness, nervousness, or anxiety, especially in individuals who are sensitive to caffeine or other stimulants. ( 1 )
Increased heart rate and blood pressure
Caffeine, and other similar stimulants, can elevate heart rate and blood pressure, potentially leading to palpitations or irregular heartbeat in susceptible individuals. Excessive consumption of pre-workout supplements or combining them with other sources of caffeine can exacerbate these effects. ( 1 )
Digestive issues
Certain ingredients in pre-workout supplements, such as caffeine, creatine, or sweeteners, may cause gastrointestinal discomfort or digestive issues like nausea, bloating, or diarrhea, particularly when taken on an empty stomach or in high doses. ( 1 , 9 , 10 )
Insomnia and sleep disturbances
If you work out at night, that should be one of the considerations you make when choosing a pre-workout. Consuming pre-workout supplements containing stimulants like caffeine too close to bedtime can interfere with sleep patterns and lead to insomnia or disrupted sleep. Avoid taking pre-workout supplements within several hours of bedtime to minimize sleep disturbances. ( 11 )
Allergic reactions
As with any food or supplement, individuals may experience allergic reactions to certain ingredients or additives in pre-workouts. Symptoms of allergic reactions may include itching, rash, swelling, or difficulty breathing and require immediate medical attention.
When using pre-workout supplements, it’s essential to carefully read product labels, start with a low dose to assess tolerance, and listen to your body’s response. If you experience persistent or severe side effects, discontinue use and consult with a healthcare professional. Additionally, individuals with underlying health conditions, such as cardiovascular issues or sensitivity to stimulants, should exercise caution and seek medical advice before using pre-workout supplements.
FAQs
Does pre-workout help build muscle?
Pre-workout supplements don’t directly build muscle. However, they may indirectly support muscle building by enhancing workout performance and increasing energy levels. Ingredients like caffeine can boost endurance, which may allow for longer and more intense training sessions and contribute to muscle growth over time. To effectively build muscle, you’ll need to pair your pre-workout supplements with a proper diet, sufficient rest, and a consistent workout routine focused on progressive overload and muscle stimulation.
How long does pre-workout last?
The effects of pre-workout typically last between 1 to 3 hours, depending on the ingredients, dosage, individual tolerance, and metabolism. Caffeine, a common ingredient, peaks in the bloodstream within 30 to 60 minutes and can last up to 10 hours in some individuals. Avoid taking a caffeinated pre-workout too close to bedtime to prevent sleep disturbances.
Does pre-workout go bad?
Yes, like any supplement, pre-workout can go bad. Check the expiration date on the packaging and store it in a cool, dry place to maintain its potency and safety. If it changes color or texture or smells bad, it’s likely spoiled and should be discarded. Some people may notice a fishy smell when pre-workout has gone bad.
When is the best time to take pre-workout?
The best time to take a pre-workout is typically 30-60 minutes before exercising. This allows the ingredients to be absorbed and take effect during your workout, maximizing energy and performance. However, you should always follow the specific instructions on the pre-workout supplement you’re using and consider your personal tolerance to ingredients like caffeine.
These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any diseases.
Our experts
Robert Wildman, Ph.D., RD, LD, CISSN, FISSN
“Dr. Rob” is a globally renowned exercise, fitness, and nutrition expert who speaks around the world on exercise and sport nutrition, and continues to work with professional and elite athletes to achieve their highest level of performance as well as health and fitness. Rob received his Ph.D. from The Ohio State University, earned his MS from Florida State University, and earned his BS from the University of Pittsburgh. He is also a registered and licensed dietitian.
Chris Mohr, Ph.D., RD
Dr. Chris Mohr is an internationally recognized subject matter expert and speaker and performance coach. Through his facilitation and online resources, he works closely with some of the largest corporations in the world including Deloitte, Delta Airlines, Johnson & Johnson and more to help busy executives all over the world, develop the energy to thrive personally and professionally.
Lily Moe
Lily is a Brooklyn-based writer and editor with over seven years of experience in health media. As a former Fitness Coach, Lily’s editorial prowess has largely focused on fitness, nutrition, and weight management. She has also spent a fair share of time in testing labs, analyzing everything from protein powders to yoga mats. Her work has appeared in Verywell Fit, Verywell Mind, Health, and more.
Jessica Coulon
Jessica is a contributing editor and writer for Fortune Recommends™ who specializes in fitness, health, nutrition, and science content. Previously, she was an editor for Popular Mechanics and Bicycling, where she covered pro cycling news, wrote how-to guides, and tested all the latest and greatest bike gear. She was also a regular shoe tester and contributor for Runner’s World. You can often find her skiing or riding her mountain bike, and racing with the F1RE female enduro team.
Kelly Uhler
Kelly has a multifaceted background in elder care, health care, and copywriting. She has worked for organizations such as A Place For Mom and Homecare.com, which gave her the opportunity to work closely with families, providing reliable information to help them make informed decisions about their loved one’s health, safety, and quality of life.
Melissa Boufounos
Certified Holistic Nutritionist
About Author
Melissa Boufounos is a certified holistic nutritionist, nutrition writer, and lifelong athlete in the greater Ottawa, Ontario, Canada area. She specializes in sports nutrition and works with teen hockey players and competitive obstacle course race athletes in her virtual private practice MB Performance Nutrition .