​​6 Best Non-Stim Pre-Workouts of 2024, Personally Tested by Our Experts

Many of the best pre-workout supplements pack healthy doses of caffeine, which may not jive with the diets and training schedules of many athletes. Thankfully, many brands have begun to release caffeine-free alternatives. Rather than focusing on the energy boost, the best non-stim pre-workouts instead hone in on other aspects of the supplement, including workout endurance, blood flow, and more. 

Of course, removing a key ingredient places added emphasis on other components to reap similar results. BarBend’s expert testers got their hands on dozens of different non-stim pre-workouts to see which ones could deliver a pump without making our hearts flutter. Grab a steaming cup of decaf, relax, and dive into our picks for the best non-stim pre-workouts available today.

The 6 Best Non-Stim Pre-Workouts of 2024

• Best Non-Stim Pre-Workout Overall: Transparent Labs Stim-Free
• Best Non-Stim Pre-Workout for Muscle Gain: Onnit Total Strength and Performance 
• Best Non-Stim Pre-Workout for Pump: Legion Pulse (Caffeine-Free)
• Best Non-Stim Pre-Workout for Cardio: 1st Phorm Endura-Formance
• Best Budget Non-Stim Pre-Workout: Naked Nutrition Naked Energy
• Best All-Natural Non-Stim Pre-Workout: Genius Pre

Editor’s note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. The opinions and articles on this site are not intended for the diagnosis, prevention, and/or treatment of health problems. It’s always a good idea to talk to your doctor before beginning a new fitness, nutritional, and/or supplement routine. 

Best Non-Stim Pre-Workouts Video Review

Join BarBend expert tester Jake Herod, NASM-CNC, and registered dietician nutritionist Chelsea Rae Bourgeois, MS, RDN, LD, as they discuss some of the best non-stim pre-workouts on the market in 2024, with a focus on pre-workouts from brands like Legion, Transparent Labs, and Onnit.

https://www.youtube.com/watch?v=XW7ubnaMY5o

How We Tested and Chose the Best Stim-Free Pre-Workouts

The BarBend team is made up of competitive athletes, certified personal trainers, and lifelong fitness enthusiasts. To determine the best non-stim pre-workouts available today, we’ve tested 68 different profiles from the industry’s best brands, using a multi-point methodology to rate each profile on a scale of 1 (lowest) to 5 (highest). Below are some of the categories and components that played into our rankings.

Ingredient Formulation

Non-stim pre-workouts require other ingredients to counteract the absence of an energy-boosting component like caffeine, and those results can’t be achieved without researched-backed dosages. 

When looking at the best-performing stim-free pre-workouts, we want to ensure that most, if not all, vital ingredients are served in an effective manner. Beta-alanine in the mix? We’re aiming for at least 3,000 milligrams. Citrulline? There better be at least 6 grams for the supplement to garner our attention. 

Our tester mixing Genius Pre

We also kept a keen eye out for any non-stim pre-workouts harboring proprietary blends. While the inclusion of this clouded mixture of ingredients is common in the supplement category, we tend to favor picks with transparent ingredients lists. 

Yes, there are some pre-workout formulations that use a proprietary blend (or two) in this roundup, but we’ve done our best to indicate this to help you make the most knowledgeable decision possible when it comes to building your personal supplement regimen.

Solubility

A pre-workout powder is sort of useless if it can’t mix properly before hitting the weights, right? To test this, we employed multiple preparation methods to see which supplements dissolved easily, and which can leave you shaking that shaker bottle for the entire drive to the gym.

We also took our time with these concoctions to determine how balanced and consistent they stayed over time. Do they require an extra shake in between sips? Does the pre-workout leave you with more “floaties” or separated powder than desired? We found out — and have the tired arms to prove it.

Price Per Serving

Given the complexity of ingredients in most pre-workouts, finding a suitable, effective option often falls into that “get what you pay for” category. With that said, most well-to-do stim-free pre-workouts cost between $1.50 and $2.50 per serving. We’ve done our best to give you a solid blend of budget-friendly and splurge-worthy options with as accurate of price tags as possible, too.

Taste and Flavor Options

As subjective as taste can be, we still think it’s a worthwhile component to call out with certain pre-workouts. After all, aren’t you more inclined to try out a flavor if you know others like it as well? 

Our tester with Transparent Labs Stim-Free Pre-Workout

We’ve also taken a look at flavor offerings across popular brands. More options within a certain profile can help eliminate potential burnout over time, and a stim-free pre-workout with multiple options can cater to larger audiences from the start. Plus, it can give you a nice sense of insurance if you really dig a certain ingredient’s makeup — no need to wince through every serving or find just how long it takes for a pre-workout to go bad. 

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

Just because you’re exercising in the evening (or just don’t love caffeine), doesn’t mean you have to forego pre-workout completely. Transparent Labs Stim-Free Pre-Workout has no caffeine but packs ingredients to help energize your training session.

This stimulant-free pre-workout contains high doses of classic pre-workout ingredients to support blood flow and focus along with some extras. A hearty dose of 4,000 milligrams of 2:1:1 BCAAs can also help boost endurance, improve recovery, and muscle building, too. (6)

Transparent Labs Stim-Free Pre-Workout

“I love that Transparent Labs’ Stim-Free pre-workout is free of artificial sweeteners, colors, and preservatives,” said Chelsea Rae Bourgeois, M.S., RDN, LD, while assessing the product for BarBend. Rating the formulation a 4.5 out of 5, she touted its BCAAs as a key component of her high score. 

She did, however, have a small issue with the pre-workout’s use of SenActiv, a patented blend of two adaptogenic compounds. “While the compounds themselves aren’t alarming, we just don’t know how much of each is included in the pre-workout supplement,” she said. “Since they’re not regulated by the FDA, I prefer to know exactly what and how much of it I’m consuming in my dietary supplements.”

In terms of taste, we rated the mixture a 3 out of 5. “I opted for the Cherry Limeade,” said our tester. “It was definitely tart, but not overly sweet like I’ve experienced with other Transparent Labs flavors.” 

To unlock this perk, though, be sure to give this stim-free pre-workout a good mixing, as clumps and “floaties” were noticeable within our shaker bottles when it came time to hit the gym. As such, we gave it a 2.75 out of 5 on our solubility scale, but our tester noted the “high-quality ingredients and ‘extras’ in the formula” weren’t diminished in their estimation by a few loose chunks. 

The fulfilling formulation of Transparent Labs Stim-Free also boasts 4,000 milligrams of beta-alanine. This is within the recommended range for a proper serving, but those sensitive to the tingling sensation may fare better with another non-stim pre-workout from this roundup. “The tingles are fierce,” said our tester. “I get itchy fingertips and lips for roughly 10 to 15 minutes after a dose. It was a bit bracing at first.”

We also enjoyed this pre-workout for muscle-building, thanks to the inclusion of taurine and L-tyrosine. Our tester praised these ingredients, as they gave a heightened sense of focus when hitting the weights. This can be a good perk to have in your pocket when trying to boost your muscular physique. Improved focus can keep you zoned in on training to failure with few distractions along the way.

Read our full Transparent Labs Stim-Free Review.

Best Non-Stim Pre-Workout for Muscle Gain: Onnit Total Strength and Performance

If your main focus for supplementation is building strength and improving recovery, you’ll want a pre-workout that’s stacked with ingredients that support both. This pre-workout is dosed with ingredients like BCAAs and glutamine, which work to promote muscle gain, recovery, and pump. It still steers clear of stimulants, though, swapping out caffeine for vitamins B6 and B5, which can provide an energy boost. 

“I like that this product is caffeine-free, and that they included important nutrients like vitamins B6 and B5,” said Chelsea Rae Bourgeois, M.S., RDN, LD, while assessing the product for BarBend.

Onnit Total Strength + Performance Review

That said, she knocked her rating for the formulation down to a 3.7 out of 5 because Onnit doesn’t clarify how much of each ingredient is in its multiple proprietary blends. “I love that it provides the ever-important BCAAs, but each scoop provides just under 3 grams total. Plus, they’re part of a proprietary blend with other ingredients, so we have no idea how much of each amino acid we’re getting per scoop. We don’t even know the ratio,” she said. 

“Based on the ingredients included in the blends, it can support physical performance during your workout and protein synthesis afterwards,” she continued. “If there was more transparency, I would score it higher.”

Our tester appreciated how well this stim-free pre-workout mixed in a shaker bottle, awarding it a 5 out of 5 in terms of solubility for leaving no “floaties” or settled powder at the base of their cup. 

Actually drinking the mix, however, was a bit challenging. After trying the Strawberry Lemonade, they said, “The best comparison I can think of in terms of taste is a stale, chalky piece of hard candy.” With this in mind, it may be best to opt for the Pink Grapefruit variety, but we nevertheless rated Onnit’s mix a 1 out of 5 in terms of taste.

Despite the hefty presence of proprietary blends, Onnit does use third-party testing with this non-stimulant pre-workout, which gave our overall rating a boost. Bourgeois loved that it was certified by Informed Sport, a reputable organization that “tests every single sports supplements batch for banned substances before being released to market,” per the regulating entity’s website.

If your biggest desire for a pre-workout is for it to have performance and recovery ingredients, you’ll have a hard time beating this formula. It contains a unique list of ingredients that may help boost your focus and pump, as well as ones that may help improve recovery between intense workouts. If you can look past the proprietary blends — and the pricier $2 price per serving (a 1 out of 5 in terms of value) — this could be a winner for those pre-training fuel-ups.

Read our full Onnit Total Strength + Performance Review.

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

After testing dozens of their products over the years, we’ve become big fans of Legion, a supplement company that foregrounds transparency with clear labeling, third-party testing, and a total lack of proprietary blends. The non-stim version of Legion’s Pulse pre-workout, which we consider one of the strongest pre-workouts on the market, wins our overall best spot for boosting blood flow and supplying a pump, thanks to the 8,000 milligrams of l-citrulline. (3)

“I love that Legion Pulse is available with or without caffeine, and there’s no added sugar, food dyes, or other chemicals,” said Chelsea Rae Bourgeois, M.S., RDN, LD, while assessing the product for BarBend. “Plus, It’s third-party tested for safety, giving you that extra peace of mind.” She rated the formulation a 4.5 out of 5. 

Aside from caffeine and l-theanine, this version of Pulse contains the same ingredients as its counterpart, including a 300-milligram dose of alpha-GPC. According to several studies, this ingredient can help compensate for a lack of caffeine by potentially increasing motivation and enhancing cognitive performance in individuals. (1)(2)

Legion Pulse Pre-Workout mixed up.

As is the case with all of Legion’s products, the ingredients list on this supplement is appealingly slim, with no artificial sweeteners, food dyes, or added sugars. We were mixed on the taste of the caffeinated Pulse. “I think it’s got a nice sweetness, but there is a bitter quality and the sweetener can leave a bit of an odd aftertaste,” said our tester, who rated its taste a 4 out of 5. You’ll find plenty of variety, though, as there are currently eight flavors available. We do, however, wish there was an unflavored option. 

We’re also disappointed that each tub contains just 20 servings, which is 10 less than you’ll find in non-stim pre-workouts like Transparent Labs Non-Stim or 1st Phorm Endura-formance. Considering it costs $2.25 per serving, which is between $0.25 and $0.75 cents more per serving than other top pre-workouts, we rated its value a 2 out of 5.

Read our full Legion Pulse Pre-Workout Review. 

Best Non-Stim Pre-Workout for Cardio: 1st Phorm Endura-Formance

Pre-workouts aren’t just for strength athletes. As its name suggests, Endura-Formance is formulated to help you push longer and harder, making it a great supplement for runners. If you’re training for a marathon, you may benefit from a scoop before hitting the pavement. 

As our tester notes, Endura-Formance has a couple compounds you won’t see in many other pre-workouts: PeakO2 and S7. PeakO2 is composed of six adaptogenic mushrooms, including cordyceps militaris, which research has shown can have positive effects on aerobic performance and training volume for endurance athletes. (13) S7, meanwhile, is a combination of seven nutraceuticals that can significantly increase nitric oxide production, per a 2021 study. (14) 

“To be honest, I don’t know if it’s actually working or if it’s the placebo effect, but I’ve been training for a triathlon and I can definitely feel it helping,” said our tester, who rated its effects a 5 out of 5.

When assessing the supp for BarBend, Chelsea Rae Bourgeois, M.S., RDN, LD, said that while she appreciates these ingredients for their potential to “improve oxygen uptake and utilization,” they are proprietary blends, meaning it’s unclear how much of each ingredient is included in each blend.

Still, she rated the overall formulation a 4.25 out of 5, with a special shout-out for its “science-backed doses” of creatine monohydrate and beta-alanine.

Our tester enjoyed other benefits from the supp’s blend of creatine, beta-alanine, betaine anhydrous, and L-tyrosine. “I use it for cardio, but I’ve pretty much started taking it before all of my workouts,” they said. “It’s particularly great for endurance, though, since it has a solid 195 milligrams of sodium.”We gave it strong marks in terms of taste (4.5 out of 5) and solubility (4 out of 5), too. 

“The Berry Lemonade flavor was excellent,” they said. “I found it slightly tart and not overly sweet. Also, no strange aftertaste.” We dinged it some in terms of solubility, as we were often left with a few loose chunks.

[Related: What Are the Side Effects of Pre-Workout?]

Best Budget Non-Stim Pre-Workout: Naked Nutrition Naked Energy

From a cost perspective, Naked Nutrition Naked Energy is among the most budget-friendly, thanks to the sub-$1 price per serving. Other non-stim pre-workouts typically cost between $1.50 and $2.50 per dose, so having a tub that doesn’t cost you heavily for each training session is a definite plus. Our team gave this product a solid 5 out of 5 for cost.

Within this additive-free, gluten-free, vegan-friendly formulation, you’ll find 1 gram of L-citrulline malate, which studies show can help improve nitric oxide production, leading to better blood flow and a more filling aesthetic in between sets. (3) While this dosage is lower than the recommended 6,000 milligrams daily, we still view this stim-free pre as a viable option for athletes wanting some NO boost in training. (18)

Our tester, a certified personal trainer, rated Naked Energy’s effects at 4 out of 5 thanks to this quick burst of blood flow, as well as the appreciated boost of energy. “I found this pre-workout to be a perfect pick-me-up for training days,” they stated. “I also didn’t experience any unwanted tingles, which I attributed to the low dose of beta-alanine.”

Scoop of Naked Nutrition Naked Energy

Naked Energy also proved to be very soluble, scoring 5 out of 5 for the category. However, while the powder did mix easily, our tester stated that the natural plant-based flavor was somewhat bitter. As such, we recommend mixing this natural pre-workout with a more flavorful beverage from the start, such as a sports drink or other workout-ready concoction.

We also like the transparency of the ingredients list, and feel Naked Nutrition is a trustworthy brand when it comes to banned substances. However, we did score Naked Energy at 3 out of 5 for third-party testing due to a lack of more extensive trials taken on by recognized certifications like Informed Sport. 

“Naked Nutrition has a third-party lab test the pre-workout for heavy metals. I would love to see more extensive testing, though, to verify potency in addition to safety,” adds Chelsea Rae Bourgeois, M.S., R.D.N., L.D..

[Related: Non-Stim Vs. Stim Pre-Workout — What’s the Best Option for Fueling Gains?]

Best All-Natural Non-Stim Pre-Workout: Genius Pre

All-natural pre-workouts are some of the cleanest blends you can buy for fueling up before training. In addition to being a caffeine-free pre-workout, Genius Pre contains no artificial flavors or added sugars. Instead, its strength-enhancing formulation is rounded out with ingredients like AlphaSize and Rhodiola rosea that can improve both your physical and cognitive performance. (11)(12)

Highlights within the formulation include 6,000mg of citrulline malate, a non-essential amino acid which has been suggested to enhance recovery and performance due to its potential to increase nitric oxide production and L-arginine bioavailability. (3) As for AlphaSize, it’s often described as a “mind-to-muscle” ingredient, with research showing that it can boost brain metabolism, improve mental focus, and lead to enhanced muscle performance. (11)

“Genius Pre is marketed as a powerhouse pre-workout, and I think the motto fits,” said Chelsea Rae Bourgeois, a registered dietitian, when assessing the product for BarBend. “I like that Genius prioritizes L-citrulline malate in this pre-workout. Each serving contains 6 grams, the upper end of what research has found to be beneficial in these types of supplements.” 

She rated the formulation a 4 out of 5, dinging it slightly for the lack of clarity of what’s included in its proprietary blends. “While a lot of the proprietary blends used in Genius Pre are becoming more common in the market, I still prefer to know exactly what is in the supplements I’m taking,” she said.

Our tester certainly felt its benefits. “I would honestly describe the effects as euphoric, like I took a mood stabilizer,” they said. “Since there’s no caffeine, I felt relaxed instead of stimulated.” They also experienced minimal jitters, noting the 2,000 milligram dose of beta-alanine, which is 1,000 to 2,000 milligrams less than you’ll find in other non-stim pre-workouts.

After taking the pre-workout, our tester worked their upper back and noticed a considerable pump in the shoulders, though it only lasted until shortly after the workout. They rated its effectiveness a 4 out of 5, adding that they’d not only take it again before a workout, but also to just “boost my focus throughout the day.”

We also loved the flavors and consistency, rating both its taste and solubility a 5 out of 5. “I tried the Blue Raspberry and loved how it sort of tasted like a blue ICEE,” they said, calling it one of the “best-tasting workouts I’ve ever had — and I’ve tried well over 50 pre-workouts.” 

[Related: Coffee vs. Pre-Workout: Which Should You Use Before Your Workouts?]

Common Ingredients In Non-Stim Pre-Workouts

Before buying a new pre-workout, it’s important to understand common pre ingredients and their purposes. When you have that base knowledge, you can make an informed decision about which formula and ingredient list may be best suited for your workout needs.

Betaine

Betaine is made in the body and can also be found in food sources like beets, broccoli, and shellfish. Betaine may be good for increasing strength and power, as two studies found proper supplementation to increase both disciplines by almost 25 percent. (4) This is likely due to the fact that betaine is a precursor to carnitine, an amino acid that can help with energy production. The effective dose of betaine for exercise performance is about 2,500mg per day, but it may be most effective when split into two 1,250mg doses. (16)

Beta-Alanine

Beta-alanine is the ingredient found in many pre-workouts that can give you that tingly feeling in your extremities. It has been suggested to delay muscular fatigue, and enhance physical performance, especially in high-intensity anaerobic workouts. (5) The suggested effective dose for beta-alanine is between 3,200mg and 6,400mg per day, although we recommend opting for a lighter serving if you find those tingles to be unpleasant. (16)

BCAAs

BCAAs, or branched-chain amino acids, are the three amino acids leucine, isoleucine, and valine. They are typically found in a 2:1:1 ratio and are most commonly utilized to help increase muscle growth, enhance exercise performance, reduce fatigue, and repair muscle damage after post-workout. (17) 

Citrulline

When used for workout performance, citrulline may help produce more nitric oxide in your system, which can up the blood flow in your muscles delivering the pumps and vascularity many athletes are chasing. It has also been suggested to be helpful for enhancing performance and recovery. (3) A clinically effective dose of citrulline is considered to be about 6,000mg per day. (18)

Creatine

Creatine is a very popular supplement and is commonly used as a driver for improved muscle growth. Creatine has been shown, in various studies, to help improve performance and muscle mass in consistent users. (19)

The conditions on its effectiveness are improved when it’s utilized in conjunction with resistance training, and its effects can be experienced by athletes of all shapes and sizes. The suggested dose of creatine will vary based on your size, muscle mass, and type of creatine, but in general, common recommendations fall between 3,000mg and 5,000mg per day after a loading period. (20)

Benefits of Non-Stim Pre-Workouts

Outside of, you know, the obvious exclusion of a stimulating ingredient like caffeine, stim-free pre-workouts can be just as influential on your workout experience as their original counterparts. Below are just a handful of the top perks that can be reaped from supplementing with these powerful powders.

Improved Blood Flow

Having better blood flow and circulation during training can lead to transient hypertrophy, or what the average gym-goer may refer to as a “pump.” Non-stim pre-workouts can help you achieve this desired phenomenon through high doses of key ingredients like citrulline, arginine, betaine (beetroot), and other nitric oxide boosters. (9)(21)

Longer Muscular Endurance

Non-stim pre-workouts may not give you an upfront burst of energy, but oftentimes include endurance and power output-focused features designed to help withstand performance from start to finish. Beta-alanine, creatine, and betaine are commonly used to facilitate this benefit. (22)(5)

Better Focus

Non-stimulant pre-workouts can be just as effective in powering your mind during training as their caffeine-enriched alternatives — they just go about it in a different way. To improve your focus and clarity during exercise, you can often see ingredients like tyrosine, taurine, alpha-GPC, and theanine commonly present in formulations. (23)(10) Other nootropics, like Huperzine A, can also be used and have been backed by promising studies supporting its effect on cognitive function. (24)

Stim-Free Pre-Workouts Vs. Regular Pre-Workouts

Regular pre-workouts generally contain stimulants like caffeine and yohimbine. These may also carry names like caffeine anhydrous, di-caffeine malate, and caffeine citrate, too, so it can be helpful to keep an eye out for those components when searching for a truly stim-free composition. Additionally, stim-free pre-workouts can often showcase circulation and pump-inducing ingredients as the main contributor in formulations, so if your powder lists, say, citrulline or betaine as its main component, odds are it’s stim-free in nature.

We’d also like to point out that stim-free workouts aren’t inherently lacking in energy. Many top-performing non-stim pre-workouts can still improve your alertness and energy levels through ingredients such as ginseng, B vitamin complexes, and other additions. (25) These components aren’t typically as potent as other stimulants, though, hence the popularity of regular pre-workouts for these needs. (26)

What to Consider Before Buying a Non-Stim Pre-Workout

We’ve had our hands on a number of stim-free pre-workouts over the years, and in that time we’ve learned how to best connect our purchases to our intended performance. Below are a few factors to keep in mind when searching for that ideal supplement for your setup.

Personal Goals

Depending on your goals, you may want more specific ingredients in your non-stim pre-workout. For example, if you intend to focus on gaining muscle, it may be wise to opt for a non-stim option with a heavy presence of creatine or other muscle-building properties.

Genius Pre-Workout

If you’re trying to withstand long, extensive sessions, look for formulations that cater to such a training style. Think about your pre-workout as just a piece of your training puzzle — the right piece with all the matching details is going to give you the best picture in the end.

Ingredients

Like your goals and aspirations, it’s important to think about your tolerances to certain ingredients as well, especially when stim-free pre-workouts can vary in robustness. If you’re sensitive to beta-alanine, for example, or want to avoid excessive tingling altogether, try to find a formulation with less beta-alanine present.

We also recommend taking your experience with pre-workouts into consideration, as this can help dictate whether you’re ready for a more extensive ingredients list. Those embarking on a beginner workout plan athletes may want to ease into pre-workout supplementation at first to help get a better understanding of what’s at play within each sip.

Research-Backed Dosages

Just because a non-stimulant pre-workout lists a key ingredient in its makeup doesn’t mean it can deliver a standard effect. The performance of these components are all reliant on proper dosing within each serving, so be sure to check whether your chosen pre-workout can leave you with just the right amount of boost for a given workout. We’ve listed many of the suggested daily dosages for key pre-workout components throughout this guide, but here’s a quick reminder for added clarity on some of the major ingredients:

• Creatine: At least 3 grams
• Citrulline: 6 grams 
• Citrulline Malate: 6–8 grams 
• Beta-Alanine: 3 grams 

Price

The price of a pre-workout will fluctuate, but it should never break the bank. It’s important to figure out what your budget is and find a pre-workout that fits your budget. We also recommend looking at the price per serving, as this can be a good point of comparison between otherwise identical products.

Final Word

Stimulant-free pre-workouts can be a great option for athletes wanting the perks of a pre-workout concoction without any excessive jitters or unnecessarily-boosted energy. Many top-performing supplements in this category can be excellent for helping promote improved focus, blood flow, muscle growth, and other benefits associated with the popular training additive. Given the specialized makeup of this pre-workout offering, however, it’s vital that athletes know what to look for when deciding between products. 

Identifying key dosages of proper ingredients, as well as how to avoid formulations containing stimulants and unnecessary fillers, is essential. Additionally, it’s not uncommon to see stim-free pre-workouts at higher price tags than their caffeine-infused counterparts. Knowing the landscape with help from this guide can go a long way in supporting your progress down to the very last drop.

FAQs

References

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