The Best Non-Stim Pre-Workout, According to a Registered Dietitian (2023)

The Best Non-Stim Pre-Workout, According to a Registered Dietitian (2023)

If you’ve taken pre-workout, you know it can be the difference between a decent workout and an epic training session. The buzzing energy, laser-sharp focus, and improved physical performance is enough to get you hooked. That is, until you experience jitters, anxiety, and the inevitable caffeine crash, leaving you irritable and fatigued. 

But don’t throw in the towel on pre-workouts just yet. A stim-free pre-workout may be the solution to achieving electric lifting sessions without the uncomfortable side effects of potent stimulants like caffeine. In this article, we share the best non-stim pre-workout supplements that will give you the energy to destroy your next workout. 

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.

How We Chose the Best Non-Stim Pre-Workout

At Breaking Muscle, we work with a team of reviewers and fitness experts who use many of the best pre-workouts on a near-daily basis. We’ve tested over 50 pre-workouts, including nearly a dozen stim-free products.

To create the list below, we specifically chose the best-non stim pre-workout supplements based on factors like quality ingredients, label transparency, flavors, taste, and budget. Our goal is to share products with evidence-based ingredients that improve focus, power, and endurance. We intentionally included goal-specific formulas for muscle growth, increased strength, and recovery. 

We included products with a variety of flavors and price points to offer something for every taste preference and budget. Ultimately, it’s important to us to share reputable brands and products with high ratings and effective formulations to support you on your fitness journey. 

Our Top Picks for the Best Non-Stim Pre-Workout Supplements

Best Non-Stim Pre-Workout Overall: Transparent Labs Stim-Free Pre-Workout

Transparent Labs Stim-Free Pre-Workout includes 13 active ingredients to enhance focus and endurance without caffeine. With ingredients like citrulline malate, beta-alanine, and taurine, it’s strategically designed to get you amped up for a high-intensity workout.

The clinically effective dose of eight grams of citrulline malate steals the show in this pre-workout. Citrulline malate converts to nitric oxide, which may improve muscle function and performance by enhancing blood flow and oxygen delivery to the muscles. (1) 

Another key ingredient, beta-alanine (four grams), improves muscle endurance, reduces muscle fatigue, and promotes muscle building. (2) If you’ve ever experienced itchy palms or arms after taking pre-workout, you can blame beta-alanine. Our product reviewer noted that she experienced intense tingling and itchy lips and fingertips after taking this product. But don’t worry, it’s just temporary — she found that it went away after about 15 minutes.

Even more, Stim-Free contains betaine anhydrous, taurine, and L-tyrosine. Betaine has been shown to help improve body composition, muscle size, and power in resistance-trained individuals (3). Studies show that taurine may boost physical performance and support muscle recovery after a workout. (4) Finally, L-tyrosine may allow for greater mental focus and endurance. 

As if you weren’t already impressed, Stim-Free also contains high-quality branched-chain amino acids (BCAAs), known for their role in muscle protein synthesis (the production of new muscle) and reducing soreness.

We could go on and on, but we think it’s fair to say Transparent Lab’s stim-free pre-workout is packed with research-backed ingredients. It’s third-party tested for banned substances and to ensure that what you see on the label is what you get. 

The product comes in eight flavors, including sour grape, peach mango, and cherry limeade. Flavors are naturally colored and sweetened with stevia. Customer reviews on the Transparent Labs website are overwhelmingly positive. One customer says, “Great taste to go along with the great pump, better performance, and no jitters or trouble sleeping.”

One of Breaking Muscle’s product reviewers agrees. She noted that the Cherry Limeade flavor was tart but not too sweet and noticed a solid muscle pump after taking it. Another one of our reviewers found it difficult to blend well in a shaker bottle, but says this shouldn’t be a dealbreaker if you drink it quickly.

Best Non-Stim Pre-Workout for Pump: Legion Pulse Stim Free

Legion Pulse Stim-Free pre-workout is made with 100-percent natural ingredients derived from plants and animals. It doesn’t contain caffeine, but it’s stacked with four performance-enhancing ingredients for the ultimate pump. 

With eight grams of citrulline malate, Pulse supports nitric oxide production for better blood flow and nutrient delivery to the muscles, which may increase muscular endurance and strength performance. (1) 

Other key ingredients include beta-alanine (3.6 grams), betaine (2.5 grams), and alpha-GPC (300 milligrams), to reduce exercise-induced fatigue, promote muscle gains, and increase power. (1)(2) One study indicated that alpha-GPC may increase physical power more than caffeine, but more research is needed. (5) 

Legion Pulse Stim-Free comes in seven flavors that are naturally sweetened with stevia and erythritol. Erythritol is a sugar alcohol that’s gotten a lot of heat recently for new studies suggesting it’s correlated with blood clotting. However, this needs to be further studied. (6) 

Customers give this product a double thumbs up for taste and effectiveness. One customer review on the Legion website says, “Smooth clean taste. Love the flavor. Keeps my focus to push through the workouts. Increased performance.”

This supplement is third-party tested, so you can have comfort knowing it’s free of banned substances and doesn’t contain harmful amounts of other contaminants.

At over $2.00 per serving, Legion Pulse Stim-Free is more expensive than some other options, but if you’re looking for a pre-workout made with natural ingredients that will get you pumped, this can be a solid choice. 

Best Affordable Non-Stim Pre-Workout: Jacked Factory Pumpsurge Caffeine-Free Pre-Workout

Jacked Factory Pumpsurge pre-workout is formulated with performance-enhancing boosters and nootropic ingredients to promote mental focus and explosive muscle pumps, and you can take it at night without worrying about not falling asleep. 

The main ingredient, L-citrulline (five grams), is a non-essential amino acid (meaning the body can produce it on its own) that increases nitric oxide, which enhances blood flow and nutrient delivery to muscles. Nitric oxide may contribute to improved muscle fullness and growth. Additionally, L-citrulline may improve strength and power during a bodybuilding workout. (7)

Other main ingredients include betaine and taurine. Research suggests betaine could enhance muscle size and body composition when combined with resistance training. (3) Furthermore, taurine may improve muscle recovery and boost endurance. (4)

What’s more, this pre-workout contains alpha-GPC, commonly classified as a nootropic for its potential ability to improve cognitive function. Alpha-GPC could support better memory, learning, and focus. 

Pumpsurge is available in Cherry Limeade, Strawberry Lemonade, and Watermelon. All options are flavored with citric acid, natural flavors, and sucralose. Sucralose is an artificial sweetener that’s considered safe for use in food. (8) 

Customer reviews on Amazon leave this product a 4.2 out of 5 stars rating. One customer writes, “I needed a non-stim pre-workout due to anxiety and heart palpitations and this stuff is perfect! The pump is great and gives me the energy I need to get through a workout.”

On the downside, this product isn’t third-party tested. Third-party tested products are tested for banned substances and potentially harmful contaminants. Ideally, supplements are third-party tested so that consumers know exactly what they’re ingesting. 

At $1.00 per serving, this product is the most affordable stim-free pre-workout on our list. That’s a bargain that’s hard to beat. 

RELATED: Best Protein Powders for Weight Loss, Muscle Gain, and More

Best All-Natural Non-Stim Pre-Workout: Naked Nutrition Pre-Workout

Naked Nutrition’s All-Natural Non-Stim pre-workout is made with 11 non-GMO, vegan, and gluten-free ingredients. It’s formulated with ingredients and micronutrients that can enhance athletic performance without the caffeine crash. 

You get two grams of CarnoSyn beta-alanine and 0.5 grams of Nitrosigine arginine silicate inositol to promote nitric oxide production for improved blood flow, focus, and energy. Nitrosigine has been shown to raise energy levels and increase muscle pump. (9) CarnoSyn is a patented beta-alanine that’s undergone rigorous testing to verify safety and quality. Over 55 clinical studies indicate that CarnoSyn helps improve focus, muscle growth, and endurance. 

Like many other pre-workouts, this includes citrulline malate (one gram) for improved muscle function and performance. However, the dose is lower than the recommended dose of eight grams daily. It also contains B vitamins (niacin, vitamin B6, vitamin B12, folate) for efficient energy production.

This all-natural stim-free pre-workout is made without artificial sweeteners, colors, and flavors. Customer reviews on Amazon generally disapprove of the “unflavored” taste, but approve of the product’s effectiveness. One customer says, “The taste is terrible but the product works. I take it 30 minutes before my workout and I get a lot of energy.”

We haven’t tried the non-stim version, but we have tested the caffeinated pre-workout and agree with this customer’s sentiments. It tastes bitter when mixed in water. We suggest mixing it in a flavored beverage to mask the taste. You can even mix it with your favorite whey protein powder for a pre-workout snack.

The product is independently third-party tested, and you can feel confident that you won’t be ingesting toxic levels of heavy metals when taking it. 

It’s priced at a reasonable $1.20 per serving — not bad for an all-natural stim-free pre-workout and cheaper than other products whose quality isn’t as good. 

Best Non-Stim Pre-Workout With Creatine: Kaged Pre-Kaged Stim Free

Kaged Pre-Kaged Stim-Free is packed with ingredients to help you dominate your next lifting session. It’s one of the few non-stim pre-workouts with creatine HCL (1.5 grams) for maximized strength and power.

Creatine is known to enhance muscle function and speed up muscle gains. Creatine monohydrate is the most researched and popular creatine on the market, but creatine HCL is starting to climb the list of the best creatine supplements. Research suggests that creatine HCL could be more absorbable and result in greater body composition changes. (10)

L-citrulline (6.5 grams) is the main ingredient of Pre-Kaged Stim-Free. As mentioned before, L-citrulline increases nitric oxide production and enhances blood flow to muscles. L-citrulline may improve strength, physical performance, and recovery. (7)

Unlike some other stim-free supplements, this one contains BCAA’s to maximize muscle protein synthesis and aid in recovery. Leucine is especially important for stimulating muscle growth and inhibiting muscle degradation. 

Other ingredients include BetaPower betaine anhydrous and Carnosyn beta-alanine to activate strength, endurance, and muscle growth.

Even more, Pre-Kaged Stim-Free includes B vitamins and L-tyrosine for improved energy and focus. Vitamin B12 supplementation has been shown to improve memory and attention in those who were deficient. (11)

There are only two flavor choices — Cherry Bomb and Fruit Punch. Both are naturally flavored and contain one gram of sugar. Customers who left reviews on the Kaged website generally approve of the taste. One customer says, “One of the best formulated pre-workouts on the market and great tasting, which is a bonus.”

The Breaking Muscle staff agrees. One of our product testers gave this pre-workout a solid 4.5 stars out 5. He used it before his afternoon workouts and loved the strong pump he got from it. He tried the Strawberry Lemonade flavor, which is no longer available as of this writing, but noted that it tasted just like a strawberry lemonade you’d get from a restaurant.

Breaking Muscle Reviews Editor Amanda Dvorak has also tried the Fruit Punch flavor in Kaged’s Pre-Kaged Sport pre-workout and claims that it’s her favorite flavor out of every other pre-workout she’s used. We think it’s safe to say that the Fruit Punch flavor in the non-stim formula is just as tasty.

At $2.25 per serving, Kaged Pre-Kaged Stim-Free pre-workout is on the more expensive side, but it’s full of energy-producing, performance-enhancing ingredients that might make it worth it. 

Best Tasting Non-Stim Pre-Workout: Ghost Pump Nitric Oxide 

Ghost Pump Nitric Oxide pre-workout is formulated to give you a massive pump without the stimulants. Ingredients are vegan-friendly, soy-free, and gluten-free.

You can choose from Sour Watermelon, Pineapple, Peach, or ‘Natty’ (a.k.a unflavored). Flavors are sweetened with stevia extract and contain zero grams of sugar. 

If one thing’s for sure, customers love the flavor of Ghost Pump Nitric Oxide pre-workout. On Amazon, one customer review says, “I had pineapple, which was tasty. Mixes pretty dang easily and in a full scoop only left a tiny amount of residue at the bottom of the cup.” Another customer that approves of the taste says, “This is a great tasting supplement and delivers the results necessary for successful workouts.”

The three grams of L-citrulline provide blood flow enhancement, which may bolster strength and support recovery. (7) Arginine nitrate (1.5 grams) also improves nitric oxide production for better oxygen delivery to the muscles and could enhance exercise performance and endurance. The final main ingredient, taurine (one gram), may amplify strength and power and play a role in recovery. (4)

Exercise can increase the production of free-radicals in the body, contributing to cellular damage and disease over time. However, Pump Nitric Oxide contains PureWay-C, a source of vitamin C that supports the immune system and protects cells from damage due to free radicals. 

The product isn’t third-party tested, which may deter athletes who value knowing that what they see on the label is what they’re getting in the product. 

At $1.00 per serving, this tasty non-stim pre-workout gives you the ingredients you need for a powerful pump at a good price. 

Best Non-Stim Pre-Workout for Focus: Genius Pre-Workout Powder

Genius Pre is a caffeine-free, nootropic-based pre-workout stacked with ingredients to help you expand your physical capabilities. Not only that but it’s formulated with cognitive-enhancing ingredients to help you stay in the zone during your workout. 

A Breaking Muscle product tester who tried this pre-workout appreciated how focused it made him during his workout. He says, “It almost felt like taking a mood stabilizer…I was relaxed, not stimulated; clear, and ready to take action.”

Genius Pre is packed with effective doses of citrulline malate (six grams), CarnoSyn beta alanine (two grams) and betaine (two grams) to elevate nitric oxide production, boost blood flow, and strengthen the mind-muscle connection for stronger, more powerful workouts.

Aside from these ergogenic ingredients, Genius Pre contains nootropics for improved cognitive function. L-tyrosine has been shown to improve cognitive flexibility during task-switching performance. (12) Moreover, alpha-GPC may support focus and memory so you’re fully engaged in your training session. Huperzine A has also been shown to improve cognitive function in certain populations, though its effects on exercised individuals are not well studied. 

Genius Pre is available in four flavors, including Sour Apple and Blue Raspberry. We especially love the Blue Raspberry flavor, which reminds us of a blue slushee. The product is free of artificial flavors and sweeteners and is sweetened with stevia.

Regarding taste and solubility, one customer review on Amazon says, “The taste is surprisingly good, which makes it enjoyable to drink. My only minor concern is that it tends to clump up occasionally, but a few extra shakes solve that.”

It’s not third-party tested, which could discourage consumers who value knowing exactly what’s in their supplements. 

At $1.89 per serving, it may not be the best option for those with a tight budget, but the nootropics may warrant the extra spending. 

Best Non-Stim Pre-Workout for Muscle Gain: Swolverine PRE

Swolverine PRE natural non-stim pre-workout combines performance-improving ingredients and antioxidant-rich superfoods for a truly unique formula. This gluten-free, vegan product is designed to help you work out harder and longer to achieve maximum gains. 

Together, citrulline malate (5 grams), beta-alanine (3.2 grams), betaine (2.5 grams), and L-carnitine (1.5 grams) delay muscle fatigue, improve body composition and muscular performance, increase power output, and aid in recovery. These functional ingredients serve to fuel harder training sessions to trigger muscle growth. 

Additionally, Swolverine PRE contains antioxidant-rich ingredients for improved blood flow and cognition. Coconut water powder contains electrolytes that support hydration. Ginseng is an adaptogen that may reduce stress and inflammation. (13) 

Swolverine PRE comes in two unique flavors — Mango Lemonade and Strawberry Dragonfruit. Flavors are sweetened with stevia and never contain artificial flavors or sweeteners. One Breaking Muscle reviews team member enjoys the refreshing taste of the Mango Lemonade flavor but noted that he tasted more mango than lemonade.

One customer review on the Swolverine website says, “Works well – definitely provides a boost in energy and focus. Tastes good. No side effects other than the expected beta-alanine tingles.”

The product isn’t third-party tested for banned substances and contaminants, and it’s on the more expensive side compared to others that cost $1.00 per serving. Though it’s pricey, it’s filled with ingredients to help you gain strength and get swole.

RELATED: Best Protein Powders for Muscle Gain

Best Non-Stim Pre-Workout for Recovery: Onnit Total Strength + Performance Stimulant-Free Pre-Workout

Onnit Strength + Performance pre-workout is a blend of adaptogens (substances that can help you adapt to stress), micronutrients, and BCAAs formulated to promote physical performance without stimulants. It’s designed with safe, clinically proven ingredients that will give you the edge you’re looking for without jitters, anxiety, or substances that make you feel unlike yourself. 

This non-stim pre-workout contains three proprietary blends for performance, power, and support.

The performance blend is made with BCAAs, glutamine, and Carnosyn beta-alanine. Glutamine, an amino acid not included in most pre-workout supplements, can help your muscles rebuild and repair themselves, reduce muscle soreness, and aid in recovery. (14) Carnosyn beta-alanine can improve muscular endurance and fights fatigue. 

The power blend contains botanical ingredients like longjack root extract and nettle root extract. These ingredients may elevate testosterone levels and muscle strength. (15)

Finally, the support blend contains red clover extract for protective antioxidants and to support hormonal balance. It also includes luteolin, which helps reduce inflammation and promote optimal testosterone production. (16)

As if that wasn’t enough, the product contains B vitamins that support energy production and relieve stress. 

Onnit Strength + Performance is only available in two flavors — Strawberry Lemonade and Pink Grapefruit. Flavors are sweetened with stevia, maltodextrin, and monk fruit extract. Customers who left reviews on the Onnit website generally agree that the product is effective but doesn’t taste great. One customer writes, “There is definitely a bump in performance with this, especially with no caffeine or stim. However, the taste is particularly bad.”

The product is third-party tested so you can feel assured you’re not ingesting harmful amounts of toxic contaminants. At $2.00 per serving, it’s pricier than several other options, but with the added glutamine and micronutrients, you may be getting your money’s worth. 

What Are the Benefits of a Non-Stim Pre-Workout?

You may already know what pre-workout supplements do, but why should you care about stim-free pre-workouts?

Non-stim pre-workouts often contain nitric oxide boosters that improve blood flow and oxygen delivery to the muscles. Increased nitric oxide production can lead to better muscle pumps and vascularity. 

They still contain energy-boosting ingredients, like Carnosyn beta-alanine and alpha-GPC, that sharpen focus and increase productivity. Additionally, many include B vitamins for energy production, so you can efficiently convert the food you eat into fuel for your workouts. 

Because they’re free of caffeine, you don’t have to worry about uncomfortable side effects like jitters, a racing heart rate, restlessness, and the inevitable caffeine crash that hits later. You can take them before an evening or late-night workout without experiencing insomnia when it’s time to get some shut-eye. 

Non-stim pre-workouts can be stacked with other supplements or beverages that may contain caffeine without surpassing what’s considered a safe amount of stimulants. It’s not recommended to exceed 400 milligrams of caffeine daily.

They’re ideal for individuals who are sensitive to caffeine or other stimulants and would like to avoid side effects while still feeling invigorated while exercising. 

What To Consider When Looking for a Non-Stim Pre-Workout

When selecting a caffeine-free pre-workout, several aspects should be taken into account to ensure it’s the best fit. 

Price

If you’re on a tight budget, look for non-stim pre-workout supplements that cost less than $2.00 per serving. Jacked Factory Pumpsurge Caffeine-Free Pre-Workout and Ghost Pump Nitric Oxide, which both cost around $1.00 per serving, will give you more bang for your buck. 

Pre-workouts that cost $2.00 per serving or more may include less common pre-workout ingredients like glutamine and creatine. These ingredients are beneficial for muscle gains and recovery, but they may not be necessary in a pre-workout if you take them separately or if they’re in another supplement you take regularly. 

Ingredients

Common non-stim ingredients include citrulline malate, beta-alanine, betaine, branched-chain amino acids (BCAAs), and taurine. These ingredients can provide powerful exercise-enhancing benefits. They promote nitric oxide production, improve endurance, stimulate muscle growth, intensify focus, and support recovery. 

Third-Party Testing

Ideally, you want to choose products that are third-party tested. Third-party testing is done by independent organizations such as Informed Choice or NSF Certified for Sport that provide unbiased evaluations of products to ensure they meet quality standards and consumer safety protocols. They test for potential contaminants and toxins to ensure consumer safety. 

Dosing

Look for non-stim pre-workouts that include ingredients in recommended dosages for the most effective results. For example, daily recommendations of L-citrulline and citrulline malate are approximately three to six grams and eight grams, respectively. Beta-alanine is effective in doses of approximately two to five grams daily. 

Final Thoughts

Stim-free pre-workout is an effective tool that can enhance exercise performance without caffeine or other stimulants that can lead to unpleasant side effects. Using science-based ingredients, like nitric oxide boosters, taurine, and betaine, the best non-stim pre-workouts improve endurance, muscle pump, strength, and recovery. These supplements are ideal for athletes who work out in the evenings, are sensitive to stimulants, or want to avoid jitters and caffeine crashes. 

Best Non-Stim Pre-Workout: Side-by-Side Comparison

FAQs

Research

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Credit: The Best Non-Stim Pre-Workout, According to a Registered Dietitian (2023)