The Best Non-Stim Pre-Workout Supplements for Evening Sweat Sessions

These pre-workout supplements fuel and hydrate your muscles without caffeine, so they’re ideal for evening workouts and those sensitive to stimulants.

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Pre-workouts are specially designed to give you that powerful “get up and go” feeling right before an intense workout. That boost you feel can partly be attributed to the high caffeine content often found in pre-workout 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 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’ve rounded up the best non-stim pre-workout supplements on the market to help you find the best effective stim-free product to meet your needs.

Our Picks for the Best Stimulant-Free Pre-Workouts:

• Best Non-Stim Pre-Workout Fat Burner: Legion Forge
• Best Non-Stim Pump Pre-Workout: Transparent Labs Pump
• Best Non-Stim Pre-Workout for Muscle Recovery: Gainful Pre-Workout (Non-Stim)
• Best Non-Stim Pre-Workout for Mental Focus: Crazy Nutrition Intensive Pre-Train Green Apple
• Best Non-Stim Pre-Workout for Muscle Gain: Legion Athletics Pulse
• Best Non-Stim Pre-Workout with Creatine: Kaged Pre-Kaged Stim-Free
• Best All-Natural Non-Stim Pre-Workout: Transparent Labs Stim-Free
• Best Non-Stim Pre-Workout for Athletic Performance: Legion Athletics Performance Surge

Best Non-Stim Pre-Workout Fat Burner: Legion Forge

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Key features and specs:

• Key active ingredients: Calcium HMB (2.5 grams), citicoline (250 milligrams), yohimbine root extract (10 milligrams)
• Who should take it: Athletes who want to optimize fat metabolism during workouts and those who workout in the morning before breakfast
• Who shouldn't take it: Anyone looking for BCAAs in their pre-workout and anyone who wants a pre-workout containing creatine
• Price per serving: $1.11 ($1.00 for monthly subscribers)
• Servings per container: 45 servings
• Flavors: N/A

Why I picked it:

Legion Forge is a pre-workout supplement that’s intended to be taken before your workout and while in a fasted state. This means that this product is likely most practical for individuals who workout in the morning prior to eating breakfast. This will help to ensure that you have gone around 12 hours without eating, which is the amount of time required to be considered fasted. During this 12 hour window, the body’s glycogen stores are depleted, which means the body must transition from burning carbohydrates for energy to using stored body fat instead (2).

Being in a fasted state is important because Legion Forge’s key ingredient is yohimbine (10 milligrams per capsule), which has been shown to boost lipolysis (fat burning) when taken prior to exercise (51). However, studies have shown that elevated insulin levels, which occur after eating, can negate yohimbine’s weight loss effects. This means that if you want to take advantage of Forge’s fat burning potential, then you need to use this product in a fasted state. That being said, a major concern surrounding fasted training is the increased risk of muscle breakdown due to the lack of protein and essential amino acids. While this is true, Forge contains a clinically effective dose of beta-hydroxy beta-methylbutyrate also known as HMB. This ingredient has been shown to have an anti-catabolic effect (52), which means it helps to preserve lean muscle mass during fasted training.

In regards to dosage, Legion suggests taking one capsule per 50 pounds of body weight 15 minutes prior to fasted training. If well tolerated, Legion advises adding one capsule per use until reaching a maximum dose of one capsule per 25 pounds of body weight. This will help to ensure you are taking a clinically effective dose of both yohimbine (0.2 milligrams per kilogram of body weight [53]) and HMB (three grams per day [54]). 

What we love:

• Formula that's designed to optimize fat metabolism during workouts
• Only $1.11 per serving (and even less for subscribers)
• No caffeine, so you don't have to give up your morning coffee (black coffee contains very few calories)

What to consider:

•  Needs to be taken in a fasted state (12 hours without food)
• Some may not want to take multiple capsules

Best Non-Stim Pump Pre-Workout: Transparent Labs Pump

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Key features and specs:

• Key active ingredients: L-citrulline (8,000 milligrams), arginine nitrate as NO3-T (2,500 milligrams), betaine anhydrous as BetaPure (2,500 milligrams), L-tyrosine (500 milligrams), L-glutathione as Setria (250 milligrams), Astragin (50 milligrams)
• Who should take it: Bodybuilders, strength competitors and anyone who wants to maximize their output during strength training workouts
• Who shouldn't take it: Those looking for a burst of energy from their pre-workout supplement
• Price per serving: $1.67 ($1.50 for monthly subscribers)
• Servings per container: 30 servings
• Flavors: Blue Raspberry, Strawberry Lemonade

Why I picked it:

Transparent Labs Pump is our choice for the best non-stim pump pre-workout because of its robust ingredients list and caffeine-free formula. Before we talk about the specifics of this supplement, let’s discuss what “pump” is in the context of working out and bodybuilding. Pump refers to the sensation of increased blood flow and muscle fullness that occurs during and after intense resistance training exercises. It’s often described as a tight, swollen or “pumped up” feeling in the muscles, which is the result of several factors, including increased blood flow and temporary muscle swelling. These effects have been shown to increase muscular endurance by increasing the amount of oxygen and nutrients delivered to the muscles during training, as well as resulting in improvements in both hypertrophy (muscle growth) and overall strength (55).

It just so happens that the three main ingredients in Transparent Labs Pump—8,000 milligrams of L-citrulline, 2,500 milligrams of arginine nitrate (as NO3-T) and 2,500 milligrams of betaine anhydrous (as BetaPure)—are designed to elicit these performance-enhancing benefits. In addition, supplements from Transparent Labs are always artificial ingredient-free and Informed Choice certified, so you can feel confident knowing what you are putting into your body. 

Regarding the taste, Pump is currently only available in two flavors: Blue Raspberry and Strawberry Lemonade. While I haven’t had the chance to test this supplement out firsthand, I have tried other Strawberry Lemonade flavored items from Transparent Labs, such as their Bulk and Lean pre-workouts, and they both tasted great.

What we love:

• Formulated to improve muscle endurance and growth
• No artificial ingredients
• Informed Choice certified

What to consider:

• Only two flavor options

Best Non-Stim Pre-Workout for Muscle Recovery: Gainful Pre-Workout (Non-Caffeinated)

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Key features and specs:

• Key active ingredients: L-Citrulline DL-Malate 2:1 (4,000 milligrams), creatine monohydrate (3,000 milligrams), beta alanine (1,500 milligrams), leucine (1,000 milligrams), isoleucine (500 milligrams), valine (500 milligrams)
• Who should take it: Individuals who want an all-natural pre-workout formula without artificial ingredients, those looking for a pre-workout that also includes recovery ingredients and those who want all the benefits of a conventional pre-workout without the caffeine
• Who shouldn't take it: Anyone who dislikes the tingling and itchiness caused by beta-alanine and anyone on a tight budget
• Price per serving: $1.85
• Servings per container: 14 servings
• Flavors: Strawberry Lemonade, Watermelon

Why I picked it:

True to its roots in customizable supplements, the Gainful pre-workout gives customers options to choose from when building their ideal pre-workout supplement. Users can opt for caffeinated or non-caffeinated, and then select their ideal intensity level: Moderate, moderate plus creatine or high intensity plus creatine. This allows users of the pre-workout to find the level that best suits their needs to better achieve their fitness goals. Note that the high intensity plus creatine and the moderate intensity options are only available for the caffeinated pre-workout, and not an option for non-caffeinated.

Dosed with BCAAs, beta-alanine and creatine (all of which are provided in amounts that are clinically effective), this potent pre-workout may aid in muscle recovery and growth. BCAAs administered before (and after) exercise promoted faster recovery (58).Gainful recommends mixing the powder with 6 to 12 ounces of water, stirring or shaking for 30 seconds to properly dissolve it, and taking the pre-workout 20 to 30 minutes before exercise for best results.

Related Post: The 10 Best Muscle Recovery Supplements

What we love:

• Vegan- and vegetarian-friendly
• Low-sugar pre-workout
• No preservatives, artificial dyes or flavors

What to consider:

• Only 14 servings per container
• Non-stim version has creatine

Best Non-Stim Pre-Workout for Mental Focus: Crazy Nutrition Intensive Pre-Train Green Apple

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Key features and specs:

• Key active ingredients: Citrulline malate 2:11 (7,000 milligrams), beta alanine (2,500 milligrams), betaine anhydrous (1,800 milligrams), L-taurine (1,000 milligrams), En-Xtra alpinia galanga (100 milligrams), KSM-66 ashwagandha (300 milligrams)
• Who should take it: Athletes looking for pre-workout that enhances focus without the jitters sometimes associated pre-workouts
• Who shouldn't take it: Those looking for a budget-friendly stim-free pre-workout
• Price per serving: $3.00/ ($2.10 for monthly subscribers)
• Servings per container: 20 servings
• Flavors: Green Apple, Blue Raspberry (caffeinated), Fruit Punch (caffeinated)

Why I picked it:

Finding a non-stim pre-workout powder that’s still able to improve your mental focus and help you stay engaged throughout your workout can be difficult. The caffeine-free Green Apple flavor of Crazy Nutrition Intensive Pre-Train is our pick for those who want pre-workout for focus without the jitters of a stimulant. 

Green Apple Intensive Pre-Train contains a wide range of ingredients you would expect to find in a high-quality pre-workout product: 7,000 milligrams of citrulline malate, 2,500 milligrams of beta-alanine and 1,800 milligrams of betaine anhydrous. It also contains key ingredients chosen to improve your mental alertness and focus; specifically, one gram of L-tyrosine, one gram of taurine and 100 milligrams of the trademarked alpinia galanga extract known as En-Xtra.

Taurine is a nonessential amino acid that appears to be effective in doses ranging from one to three grams per day (41). Supplementation may help to enhance athletic performance by increasing time to exhaustion, strength and power, as well as aid in post-workout recovery (41) and improving cognitive function (7). Tyrosine is another amino acid that’s been shown to improve both mood and energy levels because it's the precursor to the feel-good chemical dopamine (28). Tyrosine has also been shown to help individuals handle stressful situations, such as intense workouts, helping them remain focused on the task at hand (56). 

Finally, En-Xtra is a proprietary extract of alpinia galanga developed by the company OmniActive. They claim this product was developed to improve mental alertness and focus, as well as support mental energy without the crash. While research on En-Extra itself is difficult to find, there are a few scientific studies on alpinia galanga. One paper found that it induced a beneficial effect in scores of mental alertness when compared to a placebo (57). While more studies definitely need to be done on this ingredient, this supplement is worth considering if you’re looking for a stim-free pre-workout that may also have some cognitive and focus benefits. 

Note that the Green Apple flavor is the only one that’s caffeine-free. If you would prefer the caffeinated version of Crazy Nutrition Intense Pre-Train, then you should choose either the Blue Raspberry or Fruit Punch flavors. 

What we love:

• Formulated to boost exercise performance
• Aims to boost mental focus without stimulants
• Both caffeine-free and caffeinated versions

What to consider:

• Expensive
• Green Apple flavor only contains 20 servings (Blue Raspberry and Fruit Punch flavors contain 30 servings)

Best Non-Stim Pre-Workout for Muscle Gain: Legion Athletics Pulse

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Key features and specs:

• Key active ingredients: Citrulline malate (8 grams), beta-alanine (3.6 grams), alpha-GPC (300 milligrams), betaine (2.5 grams)
• Who should take it: Individuals looking for a serious “pump” during their workouts, those who prioritize building high-quality muscle mass and those who want to avoid artificial ingredients
• Who shouldn't take it: Anyone who wants to avoid the potential tingling side effect of beta-alanine and those who prefer a flavorless option
• Price per serving: $2.25 ($2.02 for monthly subscribers)
• Servings per container: 20 servings
• Flavors: Fruit Punch, Sour Candy, Green Apple, Blue Raspberry, Grape, Tropical Punch

Why I picked it:

Legion Athletics Pulse is our pick for the best stimulant-free pre-workout for muscle gain because it is specifically formulated to increase blood flow and rapidly deliver nutrients and oxygen to muscles during training.

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 (1). 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 (10).

L-citrulline also turns into L-arginine to increase gas production to widen blood vessels and increase blood flow (21). 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 (22).

Pulse also has 3.6 grams of beta-alanine per serving, which can help reduce fatigue to enhance workload, and it can increase lean muscle mass (5)(11). There are also 2.5 grams of betaine per serving. 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 (4), and one study published in the Journal of Strength and Conditioning found betaine supplementation increased total repetitions and volume load in strength-based exercise (6). 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 (12).

Finally, Pulse has 300 milligrams of alpha-GPC, which has been shown to elevate explosive performance by increasing growth hormone (GH) levels (3). GH also stimulates protein synthesis, which plays a key role in muscle growth and repair.

Pulse comes in six flavors sweetened with plant-based sweeteners, and reviews on the Legion Athletics website indicate they taste great. Reviewer Anthony P. says, “Great taste, easy to mix with no chunks, and noticeable gains.” Legion advises mixing one scoop of Pulse with 10-12 ounces of water and consuming 15 to 30 minutes before exercise.

Looking for more gains? Check out our picks for the 10 Best Supplements for Muscle Growth.

What we love:

• Over 40 peer-reviewed scientific studies support the active ingredients and doses
• Third-party tested for purity and potency
• Money-back guarantee with no return necessary
• Legion actively responds to feedback in reviews and questions

What to consider:

• No unflavored option available

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

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Key features and specs:

• Key active ingredients: L-citrulline (6,500 milligrams), BCAAs (6,500 milligrams), betaine anhydrous (2,500 milligrams), beta-alanine (1,600 milligrams), creatine hydrochloride (1,500 milligrams), coconut water powder (500 milligrams), taurine (2,000 milligrams), L-tyrosine (1,850 milligrams),
• Who should take it: Individuals looking for a pre-workout containing creatine, anyone who trains in the evening and those who want serious pumps and heightened mental focus
• Who shouldn't take it: Anyone who dislikes the tingling and itchiness caused by beta-alanine and athletes who are performing high intensity activity
• Price per serving: $2.25 ($2.02 for subscribers)
• Servings per container: 20 servings
• Flavors: Fruit Punch, Cherry Bomb

Why I picked it:

Kaged is an elite supplement brand with a premium line of products that actually work. Kaged is well known for fully dosing its formulas with the optimal ratios of ingredients to give consumers the best experience possible.

Pre-Kaged Stim-Free is our pick for the best pre-workout without caffeine with creatine because it is a well-rounded, powerful pre-workout supplement formulated to boost your energy, endurance and focus in the gym. This pre-workout contains:

• 6,500 milligrams of pure L-citrulline
• 6,500 milligrams of BCAAs (of which 4,750 milligrams is leucine, an amino acid known for its muscle building properties [23])
• 2,500 milligrams of betaine
• 1,600 grams of beta-alanine
• 1,500 milligrams of creatine hydrochloride

The inclusion of creatine is great for anyone who wants a pre-workout that has it all in one convenient scoop. Kaged uses creatine hydrochloride (HCl) instead of the more common creatine monohydrate. Although creatine HCl hasn’t been found to be any more effective than creatine monohydrate, it’s more bioavailable (24) and is the reason it’s included at 1,500 milligrams instead of the regular 5,000 milligram dose. This smaller amount is helpful for Kaged’s stim-free pre-workout since the single scoop serving size is already a whopping 27.9 grams per serving.

In addition to the numerous ingredients listed above, Kaged also includes its “neuro-focus matrix,” which includes two grams of taurine and 1,850 milligrams of L-tyrosine to improve mental focus and drive during training. This is another example of a stim-free pre-workout that has everything you need to power through your next training session.

Related Post: The Best Pre-Workouts with Creatine

Pre-Kaged Stim-Free is available in two flavors, Fruit Punch and Cherry Bomb, and is sweetened with both stevia and sucralose. Kaged advises mixing one scoop with 12 to 16 ounces of cold water in a shaker bottle 30 to 45 minutes before training. The brand also says to drink the serving entirely within 25 minutes of mixing for maximum benefits. O’Reilly tried the Cherry Bomb flavor, but said it wasn’t his favorite and the large scoops made it difficult to completely mix. “The flavor was lacking and a little too artificial for my taste,” he said. However, O'Reilly was impressed by the after-effects of this pre-workout. “The pump was massive. I love using this for a day of heavy lifting.”

Lastly, I want to highlight that this supplement is a great choice for athletes because Kaged’s supplements are tested by third-party labs and certified banned substance free.

Check out our Kaged Pre-Kaged Pre-Workout review for more information.

 What we love:

• Vegan- and vegetarian-friendly
• Third-party tested and banned substance free
• Formula includes creatine

What to consider:

• Only two flavor options available
• Artificial sweetener used to sweeten this product (sucralose)

Best All-Natural Non-Stim Pre-Workout: Transparent Labs Stim-Free

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Key features and specs:

• Key active ingredients: Citrulline malate (6,000 milligrams), BCAA 2:1:1 (4,000 milligrams), beta-alanine (4,000 milligrams), BetaPure betaine anhydrous (2,500 milligrams), taurine (1,300 milligrams), L-tyrosine (1,000 milligrams), choline bitartrate (500 milligrams), elevATP ancient peat and apple fruit extract (150 milligrams), BioPerine (5 milligrams), Huperzine A (50 micrograms)
• Who should take it: Individuals who want to avoid artificial ingredients, anyone who trains in the evening and those who want all the benefits of a high value pre-workout without the caffeine
• Who shouldn't take it: Anyone who dislikes the tingling and itchiness caused by beta-alanine and anyone who wants a pre-workout containing creatine
• Price per serving: $1.66 ($1.49 for monthly subscribers)
• Servings per container: 30 servings
• Flavors: Cherry Limeade, Sour Grape, Blue Raspberry, Green Apple, Orange, Peach Mango

Why I picked it:

Transparent Labs Stim-Free is an all-natural, caffeine-free pre-workout 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 (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).

The primary ingredients in Transparent Labs Stim-Free include:

• 6,000 milligrams of citrulline malate, which is a potent nitric oxide booster (1)
• 4,000 milligrams of beta-alanine and 2,500 milligrams of betaine anhydrous for improved endurance and performance (5)(6)
• 1,300 milligrams taurine and 1,000 milligrams of L-tyrosine for their antioxidant and cognitive benefits (7)(8)
• 4,000 milligrams of branched chain amino acids (BCAAs) to help preserve lean muscle mass during workouts (9)
• 1,000 milligrams of L-tyrosine, which may reduces the sense of fatigue felt during workouts (15)
• 500 milligrams of choline bitartrate, which may help improve attention and focus (16)
• 50 micrograms of huperzine A, which may improve performance during long duration strenuous exercise (17)

Our tester, certified personal trainer and nutrition coach Amanda Capritto, tried the Cherry Limeade flavor. She was initially put-off by the intense tingles she experienced from the beta alanine: “My lips and fingertips were really itchy for 15 minutes. I was nervous to try this pre-workout for a second time, but I am used to the tingling sensation now,” Capritto said. She was impressed with the after-effects of this pre-workout, saying, “I didn’t feel an energy boost since this is a non-stim pre-workout, but I think the combination of taurine or tyrosine helped me focus during my workout."

Related Post: Transparent Labs Review: A Complete Roundup of Transparent Labs Products

What we love:

• Formula contains 10 high-quality, evidence-backed ingredients
• Natural formula with no artificial sweeteners, flavors or colors
• 10% off subscribe and save option
• Six flavor options

What to consider:

• No unflavored option available

Best Non-Stim Pre-Workout for Athletic Performance: Legion Athletics Performance Surge

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Key features and specs:

• Key active ingredients: KSM-66TM ashwagandha extract (600 milligrams), PeakATP (450 milligrams), Alpha-GPC 50% (300 milligrams)
• Who should take it: Athletes who focus on endurance or strength training who want to up the intensity without consuming stimulants
• Who shouldn't take it: Those who want more common pre-workout ingredients, like beta-alanine, betaine anhydrous, citrulline or caffeine
• Price per serving: $1.17 ($1.05 for monthly subscribers)
• Servings per container: 30 servings
• Flavors: Blue Raspberry, Unflavored

Why I picked it:

One of the primary differences between bodybuilding and athletic performance is that athletes need to be able to generate high amounts of force as quickly as possible in game-time situations. Think about a running back being handed the ball, a volleyball player going up for a spike, a swimmer standing on the blocks before the 50-meter freestyle or a hockey, basketball or soccer player receiving a pass. In all of these situations, the player needs to rapidly maximize their force production in order to execute their goal.

This is why Performance Surge from Legion Athletics doesn’t look like other pre-workout supplements on the market. Instead of having caffeine, L-citrulline and beta-alanine, Performance Surge contains 600 milligrams of KSM-66 ashwagandha extract, 450 milligrams of PeakATP and 300 milligrams of alpha-GPC. All three of these ingredients, included in clinically effective dosage levels, were included in Performance Surge to promote improved strength, power, stamina and focus (13)(14).

If you’re interested in testing out this product for yourself, it's available in either Blue Raspberry or an unflavored option, and is sweetened with both stevia leaf extract and monk fruit. You can also feel confident knowing products from Legion Athletics are always 100 percent all-natural (free of artificial ingredients) and third-party tested by Labdoor for purity. Being caffeine-free, this product also allows you the flexibility to stack this supplement with a stim-containing pre-workout if an extra boost is necessary for an intense gym workout or training session. 

What we love:

• Formulated to support strength and anaerobic training
• Evidence-backed doses
• Plant-based sweeteners and flavors
• Gluten-free, vegetarian and vegan
• Certified to contain no banned substances

What to consider:

• Does not contain many of the ingredients commonly found in pre-workout supplements

Honorable Mentions

There are a lot of pre-workouts on the market, and while we’ve rounded up our favorites in the list above, there were others we researched that we liked as well.

Huge Supplements Pump Serum

We left this off our roundup because of the high price-per-serving and lack of third-party testing. However, our tester Kate Meier, who is a certified personal trainer and weightlifting coach, liked the Cherry Berry flavor. “It’s not very tart, and I liked that it actually tasted like cherries,” she said. Meier was impressed with the effects of this caffeine-free pre-workout. “Being stim-free, you don’t get that burst of energy you’d find in a caffeinated pre-workout, but it did get my blood pumping,” she said.

Promix Stim-Free Preworkout

While Promix Nutrition has multiple flavors for its regular pre-workout, the stim-free version is only available in a Raspberry Lemon flavor. Two scoops contain 3,200 milligrams of beta-alanine, so you may experience a tingling sensation, which some people find off-putting especially if you’re new to pre-workout. We liked that this powder contains immune supporting vitamin C and vitamin B12 which helps support the health of the nervous system.

What Is a Stim-Free Pre-Workout?

You may see these pre-workouts called stim-free, non-stim or simply pre-workout no caffeine, but all have 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 through other sources like coffee or tea. Note that the recommended daily allowance is 400 milligrams per day (25). 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 (26). 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 (27). 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 (28)(29)(30).

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 (31) and speed up post-workout recovery (32). 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 (33). 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 (34). A clinically effective dose of pure citrulline is around four grams (34), 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 (35). 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 (36). 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 (37). 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 (38).

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 increased strength and better muscular endurance (4)(39).

Taurine

Taurine is commonly found in both energy drinks and pre-workout powders because of its powerful antioxidant capabilities (40). Taurine supplementation also exhibits performance enhancing benefits, including improvements in endurance, peak power generation, electrolyte balance and improved recovery (41). 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 (15). 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 (42), but has also been shown to speed up recovery time by mitigating the muscle damage that occurs during intense training sessions (43). Creatine is effective in dosages between three to five grams per day, depending on your body weight (44).

L-Carnitine

L-carnitine is an ingredient occasionally found in pre-workout supplements marketed toward 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 (45).

Related Post: The Best Pre-Workout Supplements for Weight Loss

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 (46). 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 (47).

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 (29). 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 (48), 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 (49).

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.

Methodology: How We Chose the Best Non-Stim Pre-Workout Supplements

I'm a certified sports nutrition coach and NASM certified personal trainer who has tried countless pre-workout supplement formulas. In addition to my own experience in the fitness and supplement industry, all of these pre-workouts earn high scores when put through our scoring algorithm for non-stim pre-workout supplements. This algorithm is based on a number of factors, including:

• Ingredients for energy: Common stimulant-free ingredients that support energy include taurine, eleuthero root, niacin and vitamins B6 and B12. We look for effective doses of these ingredients for energy.
• Ingredients for hydration: Hydration plays an important role in muscle performance and recovery. We give high scores in this category to formulas that contain sodium, potassium and/or coconut water powder (a natural source of potassium).
• Ingredients for endurance: Some pre-workout formula ingredients may boost mental and physical endurance during workouts when included in effective doses. These include beta-alanine, Carnosyn, ancient peat and apple extract, rhodiola rosea, L-carnitine, eleuthero root, astragalus root extract, Astragin and Senactiv. We look for effective doses of these ingredients for endurance.
• Ingredients for reduced muscle fatigue: We look for pre-workout formulas that have ingredients that have been shown to reduce muscle fatigue. Specifically, we look for formulas that include citrulline malate and beetroot.
• Ingredients for lean muscle support: We look for 11 ingredients in effective doses that support the growth of lean muscle. Some of these ingredients are backed by more research than others, and they are weighted accordingly in the score for this section. The ingredients are creatine, betaine, leucine, taurine, isoleucine, valine, zinc, vitamin B, BCAAs, boron and calcium.
• Ingredients for focus: Improved focus can add to the intensity and intentionality of your workout. Many ingredients in pre-workout formulas included for focus either aren't backed by studies or the studies show no effect. Still, we consider the inclusion and dosing of four common pre-workout ingredients in this category, though with a much smaller weight in the overall score. They include Alpha GPC, tyrosine, huperzine A and choline bitartrate.
• Cost per serving: While price isn't always indicative of quality or value, we do reward pre-workout supplements that are more affordable, though we give this category less weight than the others.
• Sweeteners: We consider research about common sweeteners when assessing which pre-workout formulas provide the least health risks to users.
• Certifications: Third-party testing for purity and potency is rewarded in a pre-workout product's score. The most important certification for pre-workout powders is Informed Choice Informed Sport. This certification is critical for athletes who might get drug tested for their sport.
• Bonus credits: Pre-workout supplements can earn small bumps in their overall score by including antioxidants, having sustainable packaging, no proprietary blends, all-natural ingredients, non-GMO ingredients and organic ingredients (where applicable).

We also receive input from our panel of expert contributors, which includes registered dietitians and highly credentialed experts in sports nutrition and exercise science.

Learn more about our nutrition and supplement review process, as well as our stim-free pre-workout testing methodology.

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 (50), 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.

Related Post: Do Weight Loss Pills Work?

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.

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 as of publish time.

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Expert Contributors

Chris Mohr, RD and Ph.D.

Chris Mohr is a registered dietitian who holds a Ph.D. in exercise physiology. He has worked with athletes ranging from NFL players to WWE wrestlers, along with celebrities and executives worldwide. He has been a featured speaker at many conferences around the world.

Tim Ziegenfuss, PhD, CSCS, FISSN

Tim Ziegenfuss is a standout in the world of sports nutrition and exercise science, bolstered by graduate degrees from Purdue University and Kent State University. Beyond academia, he serves as a Past President and Fellow of The International Society of Sports Nutrition, steering the field toward higher standards. As CEO of The Center for Applied Health Sciences, his focus is overseeing innovative research with real-world impact and guiding product ideation and creation for major retailers all around the world.

Eddie Jo, Ph.D.

Eddie Jo is a professor of exercise physiology and the director of the Cal Poly Pomona Human Performance Research Lab. His research serves to innovate and advance the application of exercise training methodologies, nutrient intake and technologies for the optimization of human health and performance, energy metabolism, body composition and endocrine function.

Jenevieve Roper, Ph.D, CSCS.

Dr. Jen Roper is an Associate Professor of Health and Human Sciences at Loyola Marymount University. She received her PhD in Physical Education, Sports and Exercise Science in 2015 from the University of New Mexico, with a specialization in Exercise Science and Biomechanics. She currently teaches a wide variety of courses, including Nutrition, Kinesiology and Scientific Principles of Strength & Conditioning.

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