PETE NASTASI, CERTIFIED SPORTS NUTRITION COACH

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Our Picks for the Best Non-Stim Pre-Workouts of 2023:

Pre-workouts are specially designed to give you that powerful “get up and go” feeling right before an intense workout. That boost in drive can partly be attributed to the high caffeine content found in these supplements, but what about individuals who are sensitive to caffeine or who work out in the evening?

Most supplement brands now offer non-stim pre-workout products that still provide serious benefits in the gym without the caffeine. That being said, when removing a powerful stimulant like caffeine from a pre-workout, it’s even more important to ensure the other ingredients are dosed effectively and can provide the desired effects. That’s why we’re breaking down some of the best non-stim pre-workout supplements on the market to help you find the best effective stim-free product to meet your needs.

This content is meant to be informative, but should not be taken as medical advice. It is not intended for use as diagnosis, prevention or treatment of health problems. Always speak with your doctor before starting any new supplement or exercise regimen.

Why I picked it:

Pulse by Legion Athletics is a caffeine-free pre-workout that contains 14.4 grams per serving of the four active ingredients: citrulline malate, beta-alanine, alpha-GPC and betaine. These four combined work to boost muscle endurance, enhance strength, increase power and reduce fatigue without the adverse side effects of stimulants. Pulse contains no artificial substances, and every ingredient is derived from plants.

There are eight grams of citrulline malate per serving, which is an effective dose for reducing post-exercise soreness and enhancing athletic performance during high-intensity, short-duration exercise. One clinical study found that participants given six grams of citrulline malate for 16 days reported a significant reduction in fatigue and an increased production of ATP (adenosine triphosphate), an immediate energy source during vigorous training.

This supplement has 3.6 grams of beta-alanine per serving which supports performance improvements and can increase lean muscle mass. There are also 2.5 grams of betaine per serving. In a clinical study by The University of Memphis, participants given 2.5 grams of betaine for 14 days saw an increase in total repetitions and volume load during strength training. The 300 milligrams of alpha-GPC per serving supports brain health and function to keep you focused and can increase hepatic fat oxidation to utilize stored fat for energy.

Pulse is well formulated for athletes who focus on endurance or strength training. It has everything the body needs to provide energy and focus and is an excellent caffeine-free pre-workout supplement before high-intensity activity.

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Why I picked it:

Transparent Labs is a company that’s committed to holding the supplement industry to higher standards. As its name implies, total transparency is the name of the game for this company, and it vows never to use proprietary blends or artificial ingredients like sweeteners, flavors or colors in its products.

This supplement earned one of the top spots on our list for the best non-stim pre-workouts on the market because it has everything you would want to see in a high-quality pre-workout, just without the caffeine. The primary ingredients in Transparent Labs Stim-Free include:

This robust ingredient list provides everything you need to take your training session to the next level.

Stim-Free comes in six delicious flavors, and I’ve personally tried the Cherry Limeade, Peach Mango and Blue Raspberry options. They’re all naturally sweetened with stevia and tasted great without being too sweet. If I had to pick, I would say the Cherry Limeade was my favorite because it’s such a unique option, and that tart lime flavor really pops in your mouth.

For the maximum effect, Transparent Labs advises mixing a full scoop of its pre-workout powder with 12 to 16 ounces of water 30 minutes prior to training. This will definitely enhance your training session, and since it’s caffeine-free, it’s a great option for individuals who train in the evening.

One consumer review from the Transparent Labs website writes, “I am obsessed with this pre-workout. I can take it at 6 and still be in bed by 9.” If you’re looking for a high-quality, budget-friendly and caffeine-free pre-workout, then I highly encourage you to give Transparent Labs Stim-Free a try.

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Why I picked it:

Looking to get powered by plants? Swolverine Pre contains muscle-supporting, vegan ingredients to charge your muscles and help them recover when the workout’s done. Key compounds l-carnitine, beta-anhydrous, beta-alanine and citrulline malate are included to help amplify output and help your muscles push through difficult sets. After pushing your limits, these ingredients also help keep lactic acid at bay so your muscles bounce back and recover.

The not-so-secret ingredients also in Pre that promote performance are superfoods pomegranate, coconut water and Siberian ginseng to help with antioxidants and nutrient delivery. Aside from its vegan formulation, Swolverine Pre is also soy-free, non-GMO and made in the USA.

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Why I picked it:

Legion Athletics Pulse is specifically formulated to increase blood flow and rapidly deliver nutrients and oxygen to muscles during training.

The primary ingredients in Pulse include 8 grams of citrulline malate, 3.6 grams of beta-alanine, 300 milligrams of alpha-GPC and 2.5 grams of betaine all support muscle growth and endurance. Citrulline malate is L-citrulline bound to malic acid and is involved in making energy for the cells. L-citrulline turns into L-arginine to increase gas production to widen blood vessels and increase blood flow. This is because both citrulline and arginine nitrate are nitric oxide (NO) precursors in the body, and increased nitric oxide levels support vasodilation (relaxing and widening of the blood vessels), increased blood flow and improved physical performance. This is relevant to bodybuilders and individuals looking to build muscle because studies have found a positive correlation between muscle swelling and growth. Clinical studies also show that citrulline malate supplementation increased upper and lower body performance during strength training.

Beta-alanine can help reduce fatigue to enhance workload, and it can increase lean muscle mass. The amino acid betaine supports electrolyte balance to help maintain proper hydration during exercise to avoid fatigue and reduced capacity caused by dehydration. It can also increase power output and performance, and one study found betaine supplementation increased total repetitions and volume load in strength-based exercise.

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Why I picked it:

Transparent Labs Stim-Free pre-workout is a high-quality, clinically dosed, caffeine-free supplement at a price point that provides consumers with tremendous value. Most pre-workouts on the market contain anywhere from three to five active ingredients, and that’s including caffeine. Stim-Free is not only free from caffeine, but it has 10 active compounds that are all dosed effectively to provide real benefits. In addition, Transparent Labs never uses any artificial ingredients in its products (i.e. artificial sweeteners, colors, flavors or fillers).

These were the factors that motivated us to name Stim-Free the best value non-stim pre-workout on the market. It doesn’t necessarily mean that it’s the cheapest option, because there are cheaper options out there, but if you want a caffeine-free pre-workout that will actually work, then Transparent Labs has you covered.

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Why I picked it:

Swolverine’s Stim-Free pre-workout is one of the most robust non-caffeinated pre-workout supplements on the market. Pre contains all the usual ingredients found in a well formulated pre-workout, including citrulline malate, beta-alanine and taurine. What’s unique is that Swolverine also includes specific ingredients that support post-workout recovery in its formulation.

Both the betaine and pomegranate fruit powder contain antioxidant-rich plant compounds and phenolic acids that may help to reduce inflammation and improve recovery by reducing muscle soreness. This means that PRE can not only have you ready to attack your workout, but it can also help you recover quickly before your next training session.

Swolverine advises mixing one scoop of its signature Mango Lemonade flavored pre-workout with water and consuming 20 to 30 minutes before your workout.

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What Is a Stim-Free Pre-Workout?

A stim-free or non-stim pre-workout has all of the same ingredients as a conventional pre-workout supplement, just without the caffeine. These supplements are still formulated to enhance your workout, and many contain large dosages of “pump” and endurance based ingredients like L-citrulline and beta-alanine.

Stim-free pre-workouts have grown in popularity over the recent years as more information has become available regarding the importance of sleep hygiene and how caffeine can affect sleep quality. This is relevant to anyone who notices they have trouble falling asleep after taking caffeinated pre-workout before working out in the evening.

Stim-free pre-workouts are also fantastic options for people who want high performance in the gym, but who would rather consume their daily caffeine (the recommended daily allowance is 400 milligrams per day) through other sources like coffee or tea. Regardless of your reasons, if you’re looking to avoid caffeine and still benefit from the endurance, focus and drive a pre-workout can provide, then I suggest trying a stim-free supplement to maximize your performance.

If you’re on the fence and want to test out a product for yourself, many supplement companies offer individual serving samples to test out their supplements if you reach out to them via their website or social media accounts.

Benefits of Stim-Free Pre-Workouts

Stim-free pre-workout supplements are designed to enhance athletic performance, improve endurance and increase focus without relying on stimulants like caffeine. Here’s a list of the potential benefits of using a stim-free pre-workout supplement to fuel your workouts.

Improved blood flow

Ingredients like citrulline and arginine are commonly found in stim-free pre-workout supplements. These ingredients are nitric oxide precursors, which improve blood flow and increase muscle pumps during exercise. The improved blood flow is helpful for bringing oxygen and nutrients directly to the muscles to fuel your training sessions.

Increased endurance

Beta-alanine is an ingredient found in most pre-workouts that’s known to delay muscle fatigue and improve muscular endurance and workout performance. The beta-alanine is able to buffer the lactic acid in the muscles, allowing users to push out more reps of an exercise before muscle failure.

Heightened focus

Due to their lack of caffeine, stim-free pre-workouts usually contain some form of nootropics or helpful amino acids to improve focus, drive and performance in the gym. Ingredients like L-tyrosine, choline bitartrate, alpha GPC, taurine and huperzine A have all been shown to enhance cognitive function through increased focus or reduced feelings of stress and fatigue.

Enhanced performance

The combination of improved blood flow, increased endurance and heightened focus all lead to enhanced performance during training. The improved blood flow leads to more significant muscle pumps, which has been shown to improve muscle growth and speed up post-workout recovery. Increased endurance allows you to up the number of reps you perform during an exercise, and the focus is helpful for maintaining proper form and the internal drive necessary to lift heavy weights.

Stim-Free Pre-Workout Common Ingredients

Here’s a list of the most common pre-workout ingredients, what they do and the recommended effective dosages so that you can make informed decisions about which pre-workout supplement to purchase.

Citrulline or citrulline malate

L-citrulline is a precursor to the amino acid L-arginine, a powerful nitric oxide booster in the body. Nitric oxide boosters increase blood flow to muscles, which causes that classic “pumped” feeling. This also increases the amount of oxygen and nutrients that get to the muscles, which ultimately improves performance and enhances recovery. Citrulline malate is a less concentrated version of citrulline in a 2:1 ratio of L-citrulline with malic acid. The primary benefits of these two ingredients are increased muscular endurance, better aerobic capacity and reduced muscle soreness. A clinically effective dose of pure citrulline is around four grams, while citrulline malate should be dosed around six to eight grams prior to a workout session.

Arginine

Arginine, a conditionally essential amino acid, was one of the original pump ingredients included in pre-workout supplements to promote nitric oxide production in the body. Recently, it has been found that L-citrulline, a precursor to arginine in the body, is more bioavailable and increases nitric oxide production over a longer period of time.

Beta-alanine

Beta-alanine is one of the amino acids responsible for forming the compound carnosine in the body. Carnosine plays a critical role in buffering the lactic acid produced in the muscles during long durations of intense exercise. This reduction in lactic acid build-up ultimately improves endurance and exercise performance. An effective dose of four to six grams per day is advised to elicit these performance enhancing benefits. This dosage may also induce a common side effect of beta-alanine supplementation known as paresthesia, which is a sensation of prickly or tingly skin. This symptom is temporary and doesn’t cause any harm.

Betaine anhydrous

Betaine is an amino acid derivative that’s naturally found in foods like beets. Studies suggest that betaine in dosages between two and three grams may provide several performance enhancing benefits, including improved body composition, increased strength and better muscular endurance.

Taurine

Taurine is commonly found in both energy drinks and pre-workout powders because of its powerful antioxidant capabilities. Taurine supplementation also exhibits performance enhancing benefits, including improvements in endurance, peak power generation, electrolyte balance and improved recovery. The recommended dose of taurine is one to two grams taken before exercise.

L-Tyrosine

L-tyrosine is a non-essential amino acid that’s beneficial for athletic performance by enhancing focus and mood. It’s the precursor to the “feel good” hormone dopamine. Taking L-tyrosine prior to a workout has been shown to improve feelings of well-being and result in a reduced sense of fatigue. Although we think of workouts as stress relieving, intense cardio and resistance training sessions put the body under a significant amount of strain. L-tyrosine is found to work best in these stressful situations, such as intense training sessions or athletic competitions. L-tyrosine is effective in dosages between 500 to 2,000 milligrams.

Creatine

Creatine is one of the most widely used and well-studied sports supplement ingredients. It’s best known for its ability to increase muscle size and strength, but has also been shown to speed up recovery time by mitigating the muscle damage that occurs during intense training sessions. Creatine is effective in dosages between three to five grams per day, depending on your body weight.

L-Carnitine

L-carnitine is an ingredient occasionally found in pre-workout supplements marketed towards individuals with weight loss goals. A 2020 meta-analysis looked at 37 randomized controlled clinical trials and concluded that L-carnitine provided a modest reduction in body weight, despite having no clear effect on overall waist circumference or body fat percentage.

Branched chain amino acids (BCAAs)

BCAAs are one of the most popular sports supplement ingredients, and are often included in protein powders, pre-workouts, post-workouts and as standalone supplements. However, they’re also one of the more controversial athletic products, since there isn’t much scientific data supporting their muscle building or recovery claims.

BCAAs alone are ineffective at enhancing muscle recovery because they need to be consumed alongside the other essential amino acids to trigger new muscle growth and improve recovery. That being said, BCAA supplementation may be beneficial for individuals who follow plant-based diets, fail to consume enough dietary protein or for athletes who train multiple times per day. This is because plant-based protein sources are usually lower in BCAAs than meat and dairy products, so the additional BCAAs can help fill in any of the dietary gaps.

BCAAs have also been shown to act as an energy source after your muscle glycogen levels have been depleted during prolonged exercise, which is ideal for improving athletic performance.

Cluster dextrin

Cluster dextrin, also known as highly branched cyclic dextrin, is a complex carbohydrate that’s quickly and easily absorbed by the body. This makes it an ideal carb source for athletes and fitness enthusiasts who need an energy source before their workout or a post-workout recovery tool to help replenish their muscle glycogen levels after training.

AlphaSize Alpha-GPC

AlphaSize Alpha-GPC is a trademarked ingredient intended to support cognitive function, enhance muscular power output and delay fatigue. The science supports these claims, as Alpha-GPC has been shown to improve both mental and physical performance at a dose of 200 milligrams. This is due to its ability to prevent exercise-induced reductions in acetylcholine levels, which are the brain’s primary neurotransmitter molecule.

AstraGin

AstraGin is a dietary adaptogen supplement that’s a combination of Astragalus membranaceus and Panax notoginseng. Trademarked by NuLivScience, this ingredient is marketed as a way to improve athletic performance and support the natural absorption of nutrients from food. While found to be safe at 0.5 milligrams per kilogram of body weight per day, the effectiveness of AstraGin has not been well-studied, and there’s limited scientific evidence to support the performance claims.

BioPerine

BioPerine, a black pepper extract, is often included in supplements like pre-workouts and fat burners because of its ability to help enhance the bioavailability of the other nutrients you consume.

How to Choose the Best Stimulant-Free Pre-Workout for You

Effective ingredients

When purchasing a stim-free pre-workout supplement, choose a product that contains ingredients shown to be scientifically effective, such as L-citrulline, beta-alanine, betaine, taurine and L-tyrosine. You should also ensure the supplement is formulated and produced by a reputable company, contains high quality ingredients and follows good manufacturing practices.

Clinical doses

It’s important to always check the nutrition facts label to make sure that the supplement provides clinically effective dosages of the active ingredients. Regardless of the number of ingredients included in a pre-workout, if they’re underdosed, they won’t have the athletic performance benefits you’re looking for.

Positive customer reviews

It’s valuable to read a few of the customer reviews associated with the product you’re looking to purchase. They often give valuable insight into how the product performs, the best flavor options to choose and information about the company’s customer service.

Cost

The cost of a supplement doesn’t necessarily reflect the quality or effectiveness of the product. Read the ingredients label, assess whether it’s a good fit for your goals and don’t spend too much on a supplement purchase out of your budget. Remember, you can get results without athletic supplements—they’re the cherry on top of consistent training, healthy eating habits and good sleep hygiene.

Taste

The flavor of a pre-workout supplement might seem like an afterthought, especially if the product is well-dosed and effective. However, I know from experience that if you dislike the taste of the product, you probably won’t use it consistently. Consider whether you can tolerate the sweetness of artificial sweeteners like sucralose or acesulfame potassium or prefer products naturally sweetened with stevia or monk fruit.

What to Avoid in a Stimulant-Free Pre-Workout

There are a few things to avoid when choosing the right stimulant-free pre-workout for your needs.

Proprietary blends

Some pre-workouts use proprietary blends that don’t disclose the exact amount of each individual ingredient in the supplement. This makes it difficult to discern how much of each ingredient you’re consuming, and in most cases, means the ingredients are underdosed.

Artificial ingredients

Certain individuals may want to avoid artificial ingredients like sweeteners, flavors and colors that are common in pre-workout supplements. That’s why we chose products that prioritize all-natural ingredients in their supplements.

Filler ingredients

Some pre-workouts include ingredients that don’t have any proven benefits. Refer to our ingredients list above to find the ingredients to look for in your stim-free pre-workout and the dosages that are proven to be clinically effective.

How We Chose the Best Stimulant-Free Pre-Workouts

In order to find the best stim-free pre-workouts on the market, we looked at a number of different factors, including the overall quality of ingredients and dosages, customer reviews, pricing, flavors and our own first-hand experience using these products. We do our best to ensure you’re getting a high quality supplement that generates the results you’re looking for.

Stim-Free Pre-Workouts vs Regular Pre-Workouts

The only difference in a non-stim pre-workout versus a regular pre-workout should be the caffeine. All of the other performance enhancing ingredients—like L-citrulline, beta-alanine and betaine—should be included in the supplement and in the same dosages.

Despite caffeine supplementation being effective for enhancing athletic performance, it’s not always beneficial to consume a pre-workout containing caffeine. The reasons individuals may opt for a stim-free pre-workout include being very sensitive to stimulants like caffeine, preferring to get their caffeine through other sources like coffee or tea or working out in the evening close to bedtime.

Stimulant-Free Pre-Workout FAQs

Is a caffeine-free pre-workout worth it?

Absolutely, stim-free pre-workouts can still provide real benefits for athletes, bodybuilders and fitness enthusiasts looking to enhance their performance. Just make sure that yours contains ingredients that are effective and included in the correct dosages to elicit their benefits.

What makes a pre-workout stim-free?

A pre-workout is considered stim-free when it’s void of stimulants like caffeine, dicaffeine malate, theobromine and yohimbine.

How long do non-stimulant pre-workouts last?

Most of the active ingredients in non-stim pre-workouts should be ingested between 20 to 30 minutes before the gym and typically provide their performance benefits between one and two hours, depending on the individual’s metabolism and body composition.

Can you take a non-stim pre-workout before bed?

Yes, one of the primary features of a stim-free pre-workout is the suitability for use during evening workouts without interfering with your sleep schedule.

Do stim-free pre-workouts make you jittery?

Many people prefer stim-free pre-workouts if they’re sensitive to stimulants such as caffeine. If you don’t want to experience the jittery feeling that can sometimes come with the use of regular pre-workouts, then stim-free supplements may be the way to go. Supplements that contain beta-alanine may still give you a prickly sensation on your skin, but you should not experience any jitters.

Takeaway: Are Stim-Free Pre-Workouts Worth It?

Stim-free pre-workouts definitely work. I know from personal experience because I use a stim-free supplement multiple times per week when my energy levels feel solid and I don’t feel a need for caffeine to push myself through a workout. These supplements are also great pre-workout alternatives for caffeine-sensitive individuals, anyone who would rather consume their caffeine by other means or people who train in the evening before bed. Regardless of your reason for wanting to avoid stimulants, the other ingredients found in a well formulated stim-free pre-workout should still provide numerous athletic performance benefits and help you achieve your personal health and fitness goals.

Expert Contributors

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any diseases.

Prices are accurate and items in stock at time of publishing.

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Pete Nastasi, certified sports nutrition coach

BY PETE NASTASI, CERTIFIED SPORTS NUTRITION COACH

Pete Nastasi, the owner of Nastasi Nutrition, is a Certified Sports Nutrition Coach residing in North Carolina.