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Unleash Your Strength: A Comprehensive Guide to the Strongest Pre-Workouts on the Market

After trying 70+ pre-workouts, here are our top picks for the most powerful pre-workout supplements specifically formulated to help you dominate your next workout.

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When I started my fitness journey back in the early 2000s, pre-workout supplements were still a relatively new product. At that time, the supplement industry was still very much the wild west, and pre-workouts were notorious for containing now banned substances like prohormones, ephedra and DMAA, the controversial ingredient in the original Jack3d pre-workout that was banned by the FDA in 2013. 

Back then, finding the strongest pre-workout was a relatively straightforward process. You just needed to hit the local gym and ask the most jacked people there what supplements they were taking. Then, it was off to your local GNC or VitaminShoppe to replicate their supplement stack, only to likely realize you couldn’t afford it.

The majority of us can probably relate to purchasing a specific pre-workout supplement just because a friend recommended it, rather than understanding the ingredients and what they actually do. We compiled a list of the strongest pre-workout supplements currently available so you no longer need to consult your gym's jacked regulars to get their recommendations. 

We've based our choices off of personal experience—our team has tested over 70 pre-workout powders, compiling notes on pump, endurance, taste, side effects and, of course, strength. I also connected with several experts in the space to nail down what makes a pre-workout "strong." (Hint: it's not always about caffeine content.) These experts include:

  • Registered dietitian Chris Mohr, who holds a Ph.D in exercise physiology and has worked with professional athletes in the NFL and WWE
  • Registered dietitian, certified sports nutritionist and founder of the International Protein Board (iPB) Rob Wildman, Ph.D
  • Eddie, Jo, Ph.D, professor of exercise physiology and the director of the Cal Poly Pomona Human Performance Research Lab
  • Jenevieve Roper, Associate Professor of Health and Human Sciences at Loyola Marymount University, who has a Ph.D in physical education and sports and exercise science, and is a certified strength and conditioning specialist 

We discuss each pre-workout on our list in detail, reviewing everything you need to know to make an informed decision about which pre-workout will best help you achieve your personal health and fitness goals in 2024.

Our Picks for the Strongest Pre-Workout in 2024:

Strongest Pre-Workout Overall: Transparent Labs BULK Black

A black tub of Transparent Labs Bulk Black pre-workout supplement in Peach Mango flavor on a granite countertop

Key features and specs:

  • Caffeine content: 305 milligrams per serving (275 milligrams caffeine anhydrous and 30 milligrams of dicaffeine malate)
  • Active ingredients: Citrulline Malate (8,000 milligrams), Beta-Alanine (4,000 milligrams), Betaine Anhydrous (2,500 milligrams), Taurine (1,300 milligrams), L-Tyrosine (1,000 milligrams), Alpha GPC (300 milligrams), L-Theanine (200 milligrams), Theobromine (50 milligrams), Astragin (50 milligrams), Infinergy DiCaffeine Malate (30 milligrams), Boron (3 milligrams)
  • Flavors: Cherry Kiwi, Blue Raspberry, Peach Mango, Sour Gummy
  • Serving size: 21.1 grams (1 scoop)
  • Best for: Individuals looking for a pre-workout with a wide range of ingredients in evidence-based dosages for endurance and strength 
  • Not best for: Individuals who primarily perform low intensity, steady-state exercise and those with high sensitivity to caffeine and/or beta-alanine

Why I picked it:

Transparent Labs BULK Black is our best pre-workout overall for strength because of its hard-hitting formula that includes 8,000 milligrams of citrulline malate (17), 4,000 milligrams of beta-alanine (26), 2,500 milligrams of betaine anhydrous (28) and over 300 grams of total caffeine (50).

I tried the Cherry Kiwi flavor, and tester Anthony O'Reilly tried the Peach Mango flavor. The 275 milligrams of caffeine gave me an initial boost of energy within five to 10 minutes of consuming the product, and the delayed time-release effect of the Infinergy dicaffeine malate provided me energy throughout my workout. I felt it for about two hours.

O'Reilly had a similar experience. "My energy was quick and long-lasting, and I didn't crash," he said. "The strength gains were noticeable, and the focus was nuts—all I could think about was lifting more weight." I didn’t notice as much pump with this product as some others like Gorilla Mode—which has multiple pump ingredients and pure L-citrulline instead of citrulline malate—but that didn't detract from my positive experience with BULK Black.

It also mixed well and tasted pretty good. O'Reilly liked the Peach Mango flavor more than I liked the Cherry Kiwi flavor. "This tasted like a tropical drink, and it was so good that I actually want to savor slowly instead of downing it," he said. I think BULK Black tastes good, but the flavor is nothing exceptional, and I like it primarily for the formula. 

O'Reilly and I found the powder to mix easily with water in a shaker bottle, but it's a 20-gram serving size, so I use about double the amount of liquid suggested to mix it properly. If you mix with just the eight to 10 ounces of water that’s suggested, it will be tough to dissolve completely.

For more insight on this pre-workout supplement, check out our Transparent Labs BULK Black Pre-Workout review.

What we love:

  • Active ingredients included in evidence-based dosages
  • We noticed improved energy and pump using this supplement
  • Includes added vitamins and minerals (vitamin D, vitamin B6, vitamin B12, sodium and potassium)
  • Third-party tested with Certificates of Analysis for all Transparent Labs products
  • Free from artificial sweeteners, flavors and colors

What to consider:

  • We had mixed reviews on the taste (Peach Mango seems to be the best)
  • Dissolves better with 16–20 ounces of water, in our experience
A woman pouring a scoop of Strawberry Kiwi flavor Transparent Labs BULK Black pre-workout in a shaker bottle filled with water

Strongest Pre-Workout for Focus: Onnit Alpha Brain Pre-Workout

A person in a gym holding a scoop of Onnit Alpha Brain Pre-Workout powder in Tiger's Blood flavor

Key features and specs:

  • Caffeine content: 200 milligrams
  • Active ingredients: NooGandha (225 milligrams), L-Citrulline (2,400 milligrams), AlphaSize (125 milligrams), Beta-Alanine (2,400 milligrams), Dynamine (50 milligrams)
  • Flavors: Yuzu Peach, Tiger’s Blood
  • Serving size: 10.4 grams (1 scoop)
  • Best for: People who want a cognitive boost with their pre-workout to help them focus
  • Not best for: Those with caffeine sensitivity and/or those who do not have issues with focus

Why I picked it:

Onnit Alpha Brain Pre-Workout is unique on our strongest pre-workout list because it isn’t high-stim (there are only 200 milligrams of caffeine), and other common pre-workout ingredients are on the lower end of the effective dose range (like 2.4 grams of beta-alanine and 2.4 grams of L-citrulline). However, the addition of NooGandha and Dynamine make this pre-workout formula unique, and our team noticed an improvement in focus when using it before a workout.

"The other testers and I had really solid focus and clarity during our workouts without feeling over-stimulated after using this pre-workout," said Kate Meier, USAW-L1, NASM CPT, CF-L1. "It's hard to describe, but we just felt present and ready to put in the effort." Meier said that no one felt tingles after using Onnit Alpha Brain, and two testers noticed improved pump.

The improved focus our testers experienced is likely from NooGandha and Dynamine. NooGandha is a patented, concentrated ashwagandha extract that may improve cognitive function and performance and reduce the effects of stress on your body (1)(52). Alpha Brain has 225 milligrams, which meets the effective dose of 225–400 milligrams daily. 

Dynamine works as a substitute for caffeine because it has similar benefits like blocking neurotransmitters that make you tired. However, Dynamine doesn’t have the same side effects as caffeine (i.e. headache, jitters and insomnia), so the 50 milligrams in Alpha Brain function like caffeine without the side effects (51)(5).

If Onnit Alpha Brain appeals to you, we suggest opting for the Tiger's Blood flavor. Our testers passionately disliked the taste of the Yuzu Peach flavor, but enjoyed Tiger's Blood. "The taste is tropical with flavors of coconut, strawberry and watermelon," Meier said. "Both flavors mixed really well with water in a shaker bottle, but we all preferred Tiger's Blood flavor."

What we love:

  • Our testers experienced improved focus and energy during their workouts after using Onnit Alpha Brain
  • No artificial sweeteners, dyes or preservatives
  • No unnecessarily overdosed ingredients

What to consider:

  • Some ingredients are under-dosed, including AlphaSize, and others have low (though technically effective) doses, including beta alanine and L-citrulline
  • Lower dose of caffeine than many pre-workouts on this list
The Supplements Facts label of a tub of Onnit Alpha Brain Pre-Workout powder on a wooden table in a gym

Strongest Pre-Workout for Taste: Ghost Legend

A green and red container of Ghost Legend pre-workout powder in Sour Watermelon Warhead flavor on a kitchen counter

Key features and specs:

  • Caffeine content: 250 milligrams per serving
  • Active ingredients: L-Citrulline (4,000 milligrams), Beta Alanine (3,200 milligrams), Nitrosigine (1,500 milligrams), VitaCholine Choline Bitartrate (500 milligrams), Theobromine (100 milligrams), NeuroFactor Coffee (100 milligrams), AstraGin (50 milligrams)
  • Flavors: Sonic Cherry Limeade, SourPatch Kids Redberry, Warheads Sour Watermelon, Blue Raspberry, Lemon Crush, Welch's Grape
  • Serving size: 14 grams (1 scoop)
  • Best for: Individuals who want enhanced energy and focus during training, and those who want a great tasting pre-workout
  • Not best for: People who want an all-natural pre-workout without artificial ingredients and those who don't like candy-sweet supplements

Why I picked it:

The supplement brand Ghost Lifestyle is known for its flavor collaborations with popular name brand candies, cookies and drinks. The Ghost Legend pre-workout is no exception, and tastes just as true to the flavor as the Ghost protein powders. We tried the Blue Raspberry flavor, and loved the taste. O'Reilly said, "This tastes just like Blue Raspberry candy. It's similar to a Jolly Rancher. It's a little sour, but I love it, and it mixes really well, too."

While the formula isn't as high-stim as other strong pre-workouts, it still packs a punch with 250 milligrams of caffeine. "I feel pretty cracked out after using this," O'Reilly said. "I've tried at least 60 pre-workouts, and this is one of the most stimulating." O'Reilly says Ghost Legend is now one of his favorite pre-workouts because of the taste and energy, but he did notice a slight caffeine crash after the effects wore off.

Ghost Legend includes many of the major ingredients people want to see in a pre-workout formula, including L-citrulline, beta-alanine and caffeine. These ingredients could be included in higher amounts, but the doses are still effective. L-citrulline and Nitrosigine are included for pump and blood flow, and beta alanine is included for improved muscle endurance. The caffeine should help with focus and endurance.

Overall, I really like this formula because it's stimulating, without overdoing the caffeine. The flavor choices and taste are a great fit for those who struggle with the "fake" flavor of some pre-workouts. While Ghost uses artificial flavors and sweeteners, this supplement tastes like real candy, so it's an option our testers enjoyed instead of choked down.

For more insight on this pre-workout supplement, check out our Ghost Legend Pre-Workout Review.

What we love:

  • We really enjoyed the taste, and want to try the other flavors (anyone else a sour watermelon Warhead fan?)
  • Caffeine content is high, but moderate enough that you shouldn't need to avoid all caffeine the rest of the day
  • Dosed well for blood flow, endurance and focus
  • Mixes easily with water

What to consider:

  • Our tester experienced a slight caffeine crash after his workout, but he said that wasn't a deal breaker for him
  • Contains artificial flavors and the artificial sweetener sucralose

Strongest High-Stim Pre-Workout: Kaged Pre-Kaged Elite

A black and orange tub of Kaged Pre-Kaged Elite pre-workout supplement in Orange Mango flavor on a wooden table in a gym

Key features and specs:

  • Caffeine content: 388 milligrams per serving
  • Active ingredients: L-Citrulline (10,000 milligrams), Beta-Alanine (3,200 milligrams), Creatine Monohydrate (3,000 milligrams), Creatine Nitrate (2,000 milligrams), Betaine Anhydrous (2,500 milligrams), L-Carnitine (1,500 milligrams), Taurine (2,000 milligrams), Coconut Fruit Water Powder (500 milligrams), elevATP (150 milligrams), L-Tyrosine (2,500 milligrams), Caffeine (388 milligrams), Alpha GPC (300 milligrams), AmaTea (100 milligrams), Huperzine A (10 milligrams)
  • Flavors: Caribbean Sunrise, Orange Mango, Strawberry Lemonade, Glacier Grape, Fruit Punch
  • Serving size: 35.1 grams (1 scoop)
  • Best for: Elite athletes looking for an all-in-one pre-workout formulated with an extensive ingredients list (think bodybuilders and strength athletes looking to maximize muscle growth and power output)
  • Not best for: Those who are sensitive to stimulants and those new to pre-workout supplements looking for entry-level product

Why I picked it:

Kaged Pre-Kaged Elite is by far the strongest and most concentrated pre-workout powder I’ve ever tried. It's too strong for me and most other people, but if you're searching for the strongest high-stim pre-workout, it's probably just what you're after. In fact, some of our testers had built up enough of a tolerance to caffeine that the 388-milligram dose didn't phase them. 

"I feel like I have a constant amount of spikes, but no lows," said our tester Jacob Penner, USAW L2. "I wouldn't use it on a day that I need a huge burst of energy or pump, but I'd use it for standard training." Penner's response is the exception, not the rule, and I only see this being used regularly by competitive bodybuilders or weight lifters who need a really high caffeine content and a ton of pump ingredients to maximize muscle growth.

In addition to caffeine, the one-scoop serving size contains 10,000 milligrams of L-citrulline for muscular endurance and performance (54), 3,200 milligrams of beta-alanine for improved fatigue resistance (55) and 5,000 milligrams (five grams) of creatine for maximizing muscle performance during workouts (56). TL;DR: The beta-alanine is a little under-dosed, but otherwise, it's a very powerful formula.

It also tastes good and mixes well. "I really like the taste of the Orange Mango flavor. It's citrusy, but not overpowering," said Penner. "It dissolves great mixed in just a water bottle, not even a shaker bottle, and is super easy to drink. I'd use this again! I really like the flavor and the effects."

What we love:

  • 10,000 milligrams of pure L-citrulline per serving
  • Informed Choice certified and banned substance free
  • Massive dose of caffeine (please dose responsibly) 
  • Five flavor options
  • Very high value for the price (and subscribers save 10%)

What to consider:

  • 388 milligrams of caffeine, which pushes the recommended 400-milligram upper daily limit (8)
  • Contains an artificial sweetener (sucralose)
A woman in a gym pouring a scoop of Kaged Pre-Kaged Elite pre-workout powder into a shaker bottle filled with water

Strongest Pre Workout with Creatine: Gorilla Mode

A black container of Gorilla Mode pre-workout powder in Orange Krush flavor on a kitchen counter

Key features and specs:

  • Caffeine content: 200 milligrams/1 scoop, 400 milligrams/2 scoops
  • Active ingredients: L-Citrulline (5,000 milligrams/1 scoop; 10,000 milligrams/2 scoops), Creatine Monohydrate (2,500 milligrams/1 scoop; 5,000 milligrams/2 scoops), Betaine Anhydrous (2,000 milligrams/1 scoop; 4,000 milligrams/2 scoops), L-Tyrosine (2,500 milligrams/1 scoop; 5,000 milligrams/2 scoops), HydroPrime Glycerol Powder 65% (2,000 milligrams/1 scoop; 4,000 milligrams/2 scoops), Huperzine-A (100 micrograms/1 scoop; 200 micrograms/2 scoops), Malic Acid (1,500 milligrams/1 scoop; 3,000 milligrams/2 scoops)
  • Flavors: Blackberry Lemonade, Volcano Burst, Fruit Punch, Bombsicle, Cherry Blackout, Tiger's Blood, Cotton Candy Grape, Piña Colada, Mouthwatering Watermelon, Jungle Juice, Krush, Lemon Lime, Firefly Lemonade, Mojo Mojito, Strawberry Kiwi
  • Serving size: 20.4 grams (1 scoop), 20.8 grams (2 scoops)
  • Best for: Athletes who want an all-encompassing pre-workout powder that includes creatine; those who want the ability to easily halve their serving size
  • Not best for: Those new to pre-workout supplements who are looking for simple blends with minimal ingredients

Why I picked it:

Gorilla Mode Pre-Workout, developed by the YouTube bodybuilding sensation Derek from MorePlatesMoreDates, is a potent combination of active ingredients that are maxed out with pump and performance-enhancing ingredients—including 5,000 milligrams of creatine. This dose of creatine is well known for improving exercise performance, so it may enhance muscle mass and strength with resistance training (22).

Tester Jacob Penner, USAW-L2 took the Bombsicle flavor mixed with 20 ounces of water 15 minutes before his workout. "I felt improved pump almost immediately and still had pump two hours later," he said. "I felt confident, focused and energetic, but not over-stimulated." Penner also said he didn't experience any tingles (which makes sense since there's not beta alanine in the formula), but his skin felt warm. "I've tried over 50 pre-workouts, and this is now one of my favorites. I'm going to add this to my workout routine," he said.

Gorilla Mode is available in 15 flavor options. I’ve tried Blackberry Lemonade, Mango Peach and Tiger’s Blood, and they were all delicious. I’m confident in saying that Gorilla Mode is one of the best-tasting pre-workout products on the market. However, be sure to note that they do use artificial sweeteners such as sucralose and acesulfame potassium to sweeten their products. Penner said the Bombsicle flavor tastes just like rocket pop popsicles. 

What also sets this product apart from the competition is the inclusion of powerful nootropics such as L-tyrosine and Huperzine A, which are included to improve overall cognitive performance, mood and even have neuroprotective effects during stressful situations, such as intense training sessions (18)(19)(20).

For more insights on this pre-workout, check out our Gorilla Mode pre-workout review.

What we love:

  • All-in-one pre-workout supplement that contains creatine
  • Include nootropics for focus
  • Our tester got great pump, focus and energy without crashing
  • Tastes great (in my opinion) and there are lots of interesting flavors to choose from

What to consider:

  • Not the best choice for people who are caffeine-sensitive with 400 milligrams per recommended serving
  • Made with artificial sweeteners and colors

Related Post: The Best Pre-Workouts with Creatine

Strongest Pre Workout for Weight Loss: Transparent Labs Lean

A 30-serving tub of Transparent Labs Lean Pre-Workout in Strawberry Lemonade flavor

Key features and specs:

  • Caffeine content: 180 milligrams per serving
  • Active ingredients: Citrulline Malate (6,000 milligrams), Beta-Alanine (2,000 milligrams), Betaine Anhydrous (1,500 milligrams), Acetyl L-Carnitine (1,000 milligrams) Choline Bitartrate (500 milligrams), L-Theanine (180 milligrams), Theobromine (50 milligrams), BioPerine (5 milligrams),
  • Flavors: Fruit Punch, Strawberry Lemonade, Sour Grape, Sour Peach, Blue Raspberry, Green Apple, Orange, Tropical Punch
  • Serving size: 14 grams (1 scoop)
  • Best for: Individuals who want a pre-workout that helps with weight loss
  • Not best for: Athletes who want an all-encompassing pre-workout powder that includes creatine, and those looking for a highly caffeinated pre-workout supplement

Why I picked it:

If you’re entering cutting season and trying to lose weight without losing muscle mass, check out Transparent Labs PreSeries Lean. This pre-workout is designed to work as a fat burner and includes a thyroid support complex. In addition to common pre-workout ingredients like beta alanine, betaine, citrulline malate and caffeine, each serving of Lean includes 1,000 milligrams of acetyl L-carnitine, which can turn body fat into energy turning body fat into energy (12).

I've used Lean, and also asked my colleagues Nicole Davis CPT, PN1-NC and Caine Wilkes OLY USAW-L1 to try the Sour Grape flavor. "I don’t use pre-workouts very often, but I liked this one, and I'd use it again," said Caine, who is training for an international weightlifting competition. "I'm sensitive to caffeine, so the 180 milligrams was just right for me to feel focused and energized without feeling jittery." Caine said that she felt better focus and energy using Lean than Optimum Nutrition Gold Standard pre-workout, which has a similar amount of caffeine (175 milligrams).

Both Caine and Davis liked that the flavor wasn't overly sweet and didn't have an over-powering stevia aftertaste. "It's a little bitter," said Davis. Caine agreed: "The flavor was a little more sour than grape," she said. 

Both testers mixed Lean with water in a shaker bottle, and said it mixed pretty well, but had some floating clumps of dry powder. A blender or electric frother are better options for mixing Lean than a shaker bottle or hand mixing with a spoon.

What we love:

  • Our testers liked the improved focus and energy without jitters
  • Flavors aren't super sweet, like some pre-workout formulas
  • Third-party tested and certificates of analysis readily available on website
  • Doesn't contain artificial sweeteners, colors or flavors

What to consider:

  • Significantly less amount of caffeine than other pre-workouts on our list, so not the best choice for someone looking for a big jolt of energy
  • L-carnitine may interact with thyroid function, and health experts strongly recommend against taking the substance without a doctor's supervision for people with hyperthyroidism

Strongest Pre-Workout without Artificial Ingredients: Legion Athletics Pulse

A woman in a gym mixing a serving of Legion Pulse pre-workout in a shaker bottle filled with water

Key features and specs:

  • Caffeine content: 350 milligrams per serving
  • Active ingredients: Citrulline Malate (8,000 milligrams), Beta-Alanine (3,600 milligrams), Betaine Anhydrous (2,500 milligrams), Caffeine Anhydrous (350 milligrams) L-Theanine (350 milligrams), Alpha-GPC (300 milligrams)
  • Flavors: Apple Cider, Frosted Cranberry, Strawberry Margarita, Fruit Punch, Arctic Blast, Strawberry Kiwi, Blood Orange, Blue Raspberry, Blueberry Lemonade, Cherry Limeade, Grape, Green Apple, Mojito, Pink Lemonade, Sour Candy, Tropical Punch, Watermelon, Peach Ring
  • Serving size: 23 grams (2 scoops)
  • Best for: Athletes looking for a highly-caffeinated, naturally flavored and without artificial sweeteners pre-workout
  • Not best for: Those who engage in low-intensity, steady state exercise, those sensitive to caffeine and/or beta-alanine and those with cardiovascular conditions

Why I picked it:

Legion Pulse Pre-Workout has a strong, well-dosed formula and 18 flavor options without artificial flavors, colors or sweeteners. I tried the Fruit Punch flavor and liked taste, pump and energy I got from the 350 milligrams of caffeine, eight grams of citrulline malate and 2.5 grams of betaine. I also like that Pulse includes the electrolytes calcium, sodium and potassium which help keep you hydrated as you sweat (14).

Davis tried the Blue Raspberry flavor, and Penner tried the Peach Ring flavor. Both said it tasted sweet and slightly bitter. "But the effects are worth the sort of weird flavor," Penner said. They also said it mixed really well with water and didn't leave any clumps of powder after mixing in a shaker bottle.

Penner and Davis both liked the energy and pump from this pre-workout, and Penner specifically called out the inclusion of L-theanine. "The 1:1 ratio of L-theanine to caffeine was just right for me. I didn’t feel over-stimulated, just amped to be at the gym and ready to pump," he said. "This has become my favorite pre-workout for getting an energy boost without having uncomfortable side effects from a big dose of caffeine."

Check out our Legion Pulse Pre-Workout review for more insights on this pre-workout supplement.

What we love:

  • No artificial sweeteners, flavors, colors or preservatives
  • Our testers loved the L-theanine and caffeine 1:1 ratio
  • Six active ingredients included in effective doses, plus electrolytes
  • Third-party tested by Labdoor
  • “No Return Necessary” money-back guarantee

What to consider:

  • Our testers said some of the flavors have a bitter aftertaste
  • Each container has 20 servings, whereas many competitors offer 30 servings per container
The Supplement Facts label of Legion Pulse pre-workout

Strongest Pre-Workout for Blood Flow and Pump: Nutricartel El Jefe

A container of Nutricartel El Jefe pre-workout in Sour Gummy Bear flavor against a white background

Key features and specs:

  • Caffeine content: 150 milligrams (1 scoop), 300 milligrams (2 scoops)
  • Active ingredients (recommended 2-scoop serving): L-Citrulline (8,000 milligrams), Beta Alanine (4,000 milligrams), Betaine Anhydrous (3,000 milligrams), HydroPrime (2,000 milligrams), Theobromine (500 milligrams)
  • Flavors: Sour Gummy Bear, Peach Rings, Orange Creamsicle
  • Serving size: 11.3 grams (1 scoop), 22.7 grams (2 scoops)
  • Best for: Those looking for a powerful pre-workout formulated with an extensive ingredients list to maximize muscle growth
  • Not best for: Those with a sensitivity to caffeine and those who want to avoid artificial flavors

Why I picked it:

Veteran-owned Nutricartel really came out strong with its El Jefe pre-workout. It's one of the best pre-workouts for a pump, and is meant to seriously increase your blood flow during training—which not only helps to deliver oxygen and nutrients to the muscles, but also is a significant driver of hypertrophy (or muscle growth). 

The recommended two-scoop serving size contains 8,000 milligrams of L-citrulline for muscular endurance and performance (54), 300 milligrams of caffeine for maximum focus and alertness and 4,000 milligrams of beta-alanine for improved fatigue resistance (55).

Meier said her weightlifting team uses El Jefe when they want a super powerful pre-workout. Penner tried the Orange Creamiscle flavor, and tester Matt Dustin PN1-NC, CES tried the Peach Rings flavor with water. They were mixed about the taste, with Penner saying the Orange Creamsicle flavor tasted good, like an orange Smarty candy, and Matt saying the Peach Rings was one of the worst tasting pre-workouts he's tried (and he's tried dozens). 

But they were united about the energy and pump El Jefe gave them. "My sinuses actually opened up, and I felt like I could breath better after taking this pre-workout," Penner said. "It kicked in really fast. I have a high stimulant tolerance, and this gave my tons of focus without feeling like I was jumping out of my skin." Dustin agreed that pump and energy were strong—almost too strong for him since he typically uses lower-stim pre-workouts, and he used only one scoop, not two.

What we love:

  • Our testers were majorly impressed by the energy and pump
  • 10,000 milligrams of L-citrulline per serving
  • Pricey supplement ($54.99 for 20 servings), but high value
  • Veteran-owned company

What to consider:

  • A very high-stim pre-workout formula—not for those with heart conditions of stimulant sensitivities
  • Our testers strongly disliked the taste, and some even had GI upset after drinking this pre-workout

Common Pre-Workout Ingredients


Alpha-GPC is an ingredient included in pre-workout supplements to support cognitive function, enhance power output and delay muscle fatigue. The science supports these claims, as Alpha-GPC has been shown to improve both mental and physical performance at a dose of 600 milligrams (2), though some studies have shown a lower dose of 200 milligrams per day to be effective (23). Alpha-GPC works by preventing exercise-induced reductions in acetylcholine levels, which is the brain's primary neurotransmitter molecule.


AstraGin is a dietary adaptogen supplement that’s a combination of Astragalus membranaceus and Panax notoginseng. This product is trademarked by NuLivScience and 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 (24), the effectiveness of AstraGin has not been well-studied, and there’s limited scientific evidence to support the performance claims.


Beta-alanine is a non-essential amino acid that combines with L-histidine in the body to form the molecule carnosine (25). Carnosine plays a pivotal role in buffering the acidity produced in muscle cells during sets of intense exercise, and this is a major reason why it’s now included in almost every pre-workout supplement on the market. This reduction in muscle acidification improves the capacity to maximize muscular work during each set of high-intensity exercises.

The effective dose of beta-alanine is 4 to 6 grams per day (26). At this dosage level, you may experience a possible side effect of beta-alanine supplementation known as paresthesia (27). This is a sensation of hot, prickly or tingly skin that usually lasts anywhere from 10 to 15 minutes, and is completely harmless.

Betaine anhydrous

Betaine, also known as trimethylglycine, is an amino acid derivative that’s naturally found in certain foods like beets. Studies suggest that betaine in dosages between 2 and 3 grams may provide several performance-enhancing benefits. These include improved muscular endurance during exercise, which in turn may enhance strength and muscle mass development (28)(29)(30).


BioPerine is a black pepper extract, and is often included in pre-workout supplements because of its ability to help enhance the bioavailability of the other nutrients you consume (31). BioPerine essentially increases the effects of the other ingredients in a pre-workout formulation.

Caffeine anhydrous

Aside from stim-free pre-workout supplements, caffeine is found in almost every pre-workout on the market. This is due to caffeine’s ability to stimulate the central nervous system, which leads to improvements in athletic performance, cognition, power output and endurance (32). 

Caffeine is one of the most studied supplements when it comes to enhancing athletic performance and has shown to be effective in doses of 3 to 6 milligrams per kilogram of body weight. This means that, for a 150-pound individual, an effective caffeine dose for enhancing athletic performance is between 200 to 400 milligrams. When using a pre-workout at these dosages, it's important to monitor your total daily caffeine consumption. The recommended daily upper limit of caffeine for healthy adults is 400 milligrams per day (33).

Citrulline malate or L-citrulline

Citrulline malate is a two-to-one combination of L-citrulline and malic acid. The main benefits of this ingredient are increased muscular endurance, better aerobic capacity and reduced muscle soreness (13). This is because L-citrulline is a precursor to the amino acid L-arginine, which in turn is a precursor to nitric oxide in the body (34). Nitric oxide is a vasodilator, and vasodilation is a process that widens blood vessels, delivering oxygen and nutrient-rich blood to various tissues—including muscles. By increasing nitric oxide levels through citrulline supplementation, one may improve blood flow to muscles and enhance performance. An effective dose of citrulline malate is around 6 to 8 grams, and an effective dose of L-citrulline is 4 to 6 grams taken prior to a training session (13).


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 (35), but has also been shown to speed up recovery time by mitigating the muscle damage that occurs during intense training sessions (36). Creatine is sometimes included in pre-workout supplements for consumers who want a pre-workout formula that covers all of their bases. Creatine is effective in dosages between 3 to 5 grams per day, depending on your body weight (37).


L-theanine is an amino acid that works in conjunction with caffeine to improve cognition, reaction time and focus (38). The addition of L-theanine to highly caffeinated pre-workout supplements has been shown to reduce some of the unwanted side effects of high caffeine consumption, which include an increase in heart rate, restlessness and anxiety (39). The effective ratio to reduce these side effects is two-to-one L-theanine to caffeine (40).


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 (41). 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 has been found to work best in stressful situations, including intense training sessions or athletic competition.

In one study, healthy men took L-tyrosine (150 milligrams/kilogram of body mass) before cycling to exhaustion in heat and humidity. The men who took L-tyrosine cycled for longer than the placebo group but reported similar exertion levels and had a similar heart rate to those in the placebo group. The study authors concluded that L-tyrosine supplementation may have an effect on endurance capacity under stress (58). 


Taurine is an ingredient commonly found in energy drinks and pre-workout powders because of its demonstrated antioxidant effects (42) and potential athletic performance benefits. These benefits include improvements in endurance, peak power generation, electrolyte balance and improved recovery (43). The recommended dose of taurine is 1 to 2 grams taken prior to exercise.

Related Post: Common Pre-Workout Supplement Ingredients and What They Do


As long as you’re a healthy adult and using the product as intended, then there shouldn’t be any serious precautions you need to take when trying a new pre-workout. That being said, here are some general guidelines you may want to follow when using a pre-workout powder that's significantly stronger than what you’re used to.

My initial recommendation is to read the new label carefully and compare it to a pre-workout you've used in the past. If your normal pre-workout powder contains 150 milligrams of caffeine and you decide to slam a full scoop of Pre-Kaged Elite with 388 milligrams of caffeine per serving, then you may experience some unwanted negative side effects like jitters, headaches and anxiety. In this case, it may be smarter to start with a low dose, such as a half-scoop, and gradually increase to a full-serving size over time based on your tolerance.

Another potential mistake to avoid is taking pre-workout supplements too late in the evening. Most pre-workout powders contain high levels of caffeine that, when taken too close to bedtime, can interfere with your sleep.

This last one should go without saying, but be sure to follow the supplement label directions and do not exceed the recommended dosage level. For these potent pre-workouts, exceeding the recommended dose can lead to serious side effects, such as heart palpitations, anxiety or even cardiac arrest. It’s always a good idea to consult with a healthcare professional to determine if the pre-workout is appropriate for you given your health history and current medications.

When You Should Take a Strong Pre-Workout

The optimal time to take a strong pre-workout supplement is anywhere from 15 to 30 minutes before training. This will give the product enough time to digest, absorb and allow the beneficial effects to begin taking place. You may also only want to use a strong pre-workout for specific instances, such as prior to a particularly demanding workout, when attempting a new one-rep max or even to power through an early morning training session. These stronger products are also great for individuals who have built up a high tolerance to caffeine and need a more substantial dose to achieve the desired effects. Just be careful, as this can be a slippery slope—if you’re taking north of 300 milligrams of caffeine and not feeling the effects, then you may want to take a few weeks off from caffeine to readjust your tolerance levels.

When You Shouldn’t Take a Strong Pre-Workout

There are a number of instances in which taking a strong pre-workout may not be the best option. The first factor to consider is whether you’re already consuming high amounts of caffeine through other sources, such as coffee, tea, energy drinks or soda. Adding a high stimulant pre-workout supplement to an already highly caffeinated diet can cause some serious unwanted side effects, including headaches, dehydration, anxiety and insomnia.

You should also take into account your sensitivity to caffeine and other stimulants. Many pre-workout supplements contain a substantial amount of caffeine that may be tolerable for a larger individual, but too strong for a smaller one. Other factors include pre-existing medical conditions and whether you’re pregnant or breastfeeding or under the age of 18. These are all instances where you may want to avoid a pre-workout supplement or at least seek a medical professional's expert opinion.

How to Choose the Best Strong Pre-Workout for You

Stimulant content

One of the major contributing factors in classifying a pre-workout supplement as “strong” is the amount of caffeine and other stimulants in the product. Most average strength pre-workout supplements contain between 150 and 200 milligrams of total caffeine per serving, which is equivalent to about two to three cups of coffee (44). This is generally enough caffeine to give individuals the boost they need to attack their training session. 

On the other hand, if you’re a larger individual, caffeine tolerant or participate in early morning training sessions, then it may take a higher stim supplement to achieve the desired focus, drive and strength outcomes. In these cases, a “strong” pre-workout containing 250 to 400 milligrams of caffeine per serving may better suit your needs.

Active ingredients and dosage levels

The strength of a pre-workout supplement is not just about the amount of caffeine per serving. In order to stay competitive in the space, pre-workouts labeled as “strong” or “elite” need to have multiple active ingredients included in clinically effective dosage levels. The most common ingredients found in pre-workouts, aside from caffeine, include L-citrulline or citrulline malate, beta-alanine, betaine and individual amino acids like taurine and tyrosine. Refer to our individual ingredients section above to learn more about these ingredients and the dosage levels that will actually benefit the user.

Third-party testing

There are several organizations that test pre-workout supplements to ensure their safety and effectiveness, such as NSF International, Informed Sport and Labdoor. While third-party testing isn’t mandatory, this shows that the company cares about providing its consumers with high-quality, safe and effective supplements. This is also very beneficial for athletes who compete in drug-tested sports and want to ensure their products are free of banned substances.

Customer reviews

It’s always best practice to read a handful of customer reviews regarding the pre-workout supplement you’re looking to purchase. These reviews often give great insight into how the product made someone feel, the results you can expect from product use and the best flavor options to try.

Flavors options and taste

Make sure your supplements taste great and have at least one flavor profile you enjoy; otherwise, you’re less likely to actually use them. Another factor to consider is how the product is flavored and sweetened. If you prefer all-natural products, then you should read the supplement facts label carefully to see if the product contains any artificial sweeteners, colors or flavors.


It’s important to remember that the cost of a supplement doesn't necessarily reflect the quality or effectiveness of the product. You should never overspend on the purchase of a supplement. Consider your specific needs, goals and budget to make an informed decision about which product will provide you with the most value.

What to Avoid in a Strong Pre-Workout

When searching for a strong pre-workout supplement, you may have the mindset that more is better, but this isn’t always the case, and there are a few things you may want to avoid when shopping for a strong pre-workout supplement.

The first red flag is a supplement facts label that contains proprietary blends, which combine multiple ingredients and list them as a single item on the product label without disclosing the specific quantities of each individual ingredient used. This lack of transparency makes it difficult to evaluate the safety and effectiveness of the product and usually means that the product is inadequately dosed.

Athletes who participate in sanctioned drug-tested competitions also need to take precautions when trying out a new pre-workout supplement. They should ensure the product has been third-party tested and is certified safe for sport, meaning the product is free from banned substances. If you’re an athlete and don’t want to risk the chance of a failed drug test, then stick with reputable companies and products you trust rather than trying every new product to go viral.

Methodology: How We Chose the Strongest Pre-Workouts

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 algorithms for caffeinated and non-stim pre-workout supplements. These algorithms are based on a number of factors, including:

  • Ingredients for energy: Common stimulant sources of energy in pre-workout supplements are caffeine anhydrous, PurCaf, di-caffeine malate and theobromine. 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, 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 pre-workout testing methodology and stim-free pre-workout testing methodology.

Strongest Pre-Workouts FAQs

Which pre-workout has the most caffeine?

From our list, Pre-Kaged Elite has the most caffeine at 388 milligrams per serving. At this dosage level, you should monitor your intake of caffeine from other sources, especially if you're sensitive to caffeine. The FDA has determined 400 milligrams to be an amount not generally associated with dangerous, negative effects, but individual sensitivity to caffeine varies (33).

What makes a pre-workout strong?

It’s important to remember that the “strength” of a pre-workout is dependent on the specific individual using the supplement, the ingredients and the dosage levels used. For example, a 250-pound male and 150-pound female would have a different experience using the same pre-workout. In this context, we'll classify a strong pre-workout as a supplement that has multiple active ingredients (caffeine, L-citrulline, beta-alanine, betaine, taurine, etc.) included in clinically effective dosages.

Are there any side effects to taking a strong pre-workout?

Yes, there are some potential side effects associated with taking a strong pre-workout supplement. These side effects can vary depending on the ingredients in the supplement and the dosages used, as well as individual factors such as sensitivity and tolerance to certain substances. Some possible side effects include jitters, anxiety and trouble sleeping (45), as well as increased heart rate and blood pressure due to the intense caffeine levels (46) and a feeling of hot and itchy skin known as paresthesia from the beta-alanine (47). 

If you have any concerns about the safety of a particular supplement, you should consult with a healthcare professional before use. It’s also important to monitor your body's response to a new supplement and adjust your dosage and usage accordingly.

What are the benefits of using a stronger pre-workout?

Compared to an average pre-workout containing two or three active ingredients included at modest dosage levels, a stronger pre-workout should have more active ingredients, higher dosage levels and therefore more pronounced beneficial effects. These stronger pre-workouts should significantly improve your energy levels, focus, endurance and pump during training.

Does your energy crash after taking a strong pre-workout?

The answer to this question can vary significantly depending on an individual's sensitivity to caffeine, the other ingredients in the supplement and the activities performed after taking it. If you’re very caffeine sensitive, then you may experience an eventual drop in energy levels as the stimulant begins to wear off. However, caffeine has around a five-hour half life, meaning that it remains in the body for a significant amount of time, dissipates slowly and shouldn’t cause a sudden drop in energy levels (48). The energy “crash” that’s often attributed to caffeine or pre-workout is more than likely the result of the energy expended during training. This feeling is often exacerbated when using a pre-workout because the supplement increases the amount of energy you're able to utilize during your workout.

Is DMAA banned in pre-workouts?

Yes, dimethylamylamine or DMAA was banned by the U.S. Food and Drug Administration in 2013 for use in dietary supplements because it had been shown to increase the risk of cardiac events such as heart attacks (49).

Takeaway: Are Strong Pre-Workouts Worth It?

For serious athletes, bodybuilders and fitness enthusiasts, the strongest stimulant pre-workout supplements are definitely worth the often higher price point for a more potent product. Also, if you’re someone who has stayed loyal to a particular pre-workout brand, you may have noticed that the supplement just doesn’t give you the same kick it used to. Some people deal with this by taking a second scoop; however, that can be dangerous when using a pre-workout that already has more than 200 milligrams of caffeine per scoop. What normally does the trick is trying a new pre-workout that has slightly different ingredients and dosage levels. Plus, there's just something exciting about trying a new pre-workout for the first time, timing it perfectly so that you feel supercharged and ready for your workout. If you need that extra boost for your next training session, consider trying any one of the high powered supplements on this list.

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

Prices are accurate and items in stock as of publish time.

Expert Contributors

Chris Mohr, RD, 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.

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.

Eddie Jo, Ph.D.

Dr. 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.

Rob Wildman, PhD, RD, LD, CISSN, FISSN

Rob received his PhD from The Ohio State University, earned his MS from Florida State University and his BS from the University of Pittsburgh. He is a registered and licensed dietitian.He is currently Principal at Demeter Consultants, a food and dietary supplement consulting agency, and is working with several brands, including Sports Illustrated Showcase. He is the creator of and the founder of the International Protein Board (iPB), the global authority in Protein Matters. 


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