Best High Stim Pre-Workouts (350mg+ caffeine)

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Our team has tested well over 30 pre-workouts, and we’ve learned a lot about what makes these products great. This article takes a look at one specific type of pre-workout: high-stim. 

You’ll learn exactly what makes a high-stim pre-workout effective, and I’ll share our top three picks that deliver serious results.

Key Takeaways

• With its balanced formula (high in stimulants, but also having clinically effective doses of citrulline malate, beta-alanine, and other effective compounds), affordability ($1.83 per serving), and transparent lab testing of each batch, Transparent Labs Bulk Black is number one on our list.

• Legion Pulse is a worthy runner-up. It offers 350 mg of caffeine per serving and clinically effective doses of other compounds like citrulline malate. The formula also includes L-theanine, which helps offset adverse caffeine effects like anxiety. The dose per serving is $2.25.

• Ryse Godzilla is our third pick. It has the highest dose of caffeine per two-scoop serving (400 mg) and also includes clinically effective doses of ingredients with extensive research. However, a serving costs $2.84, and the product has a dairy ingredient, which is something to consider if you’re lactose intolerant.

What is a ‘High-Stim’ Pre-Workout And Who Is It For?

High-stim pre-workouts are those with a higher caffeine dosage per serving (at least 350 mg) and other stimulants like theobromine, dendrobium, synephrine, alpha-GPC, huperzine, and guayusa leaf extract.

These types of stimulants boost alertness, focus, and athletic performance, and may offer modest fat-burning benefits. 

Instead of directly influencing metabolic processes related to energy production (say, to help the body more quickly produce ATP molecules, which are the primary energy source for your muscles), they boost nervous system activity, improve pain tolerance, and make you feel less tired.

In other words, stimulants don’t help you access more energy; instead, they make you feel better, which helps you push harder at the gym.

Stimulants vs. Stim-Free Performance Boosters

These products are different from stim-free formulas which boost performance and energy levels without relying on stimulants. 

High-stim pre-workouts use ingredients like caffeine, theobromine, and synephrine to fire up your nervous system. That gives you more energy, helps you stay focused, and pushes off fatigue so you can train harder.

Stim-free pre-workouts work differently. Instead of relying on stimulants, they use ingredients like citrulline malate and beta-alanine to improve blood flow, boost endurance, and help with muscle pumps — without the jittery feeling you might get from caffeine.

Who should use high-stim pre-workouts:

• Great for trainees who work out early in the day and need a pick-me-up

• Those who do particularly demanding workouts

• People who tolerate high caffeine doses well and don’t experience adverse effects like anxiety or jitters

• Those looking to lose fat, as some stimulant may offer modest fat-burning benefits

Who shouldn’t use high-stim pre-workouts:

• Those who work out in the late afternoon or evening, as high stimulant doses can interfere with sleep

• People who don’t tolerate high caffeine doses well

• Those with a history of high blood pressure (hypertension)

• Habitual caffeine consumers who have built up a tolerance

Best High-Stim Pre-Workouts (Ranked)

1. Transparent Labs Bulk Black

Key Features

• Price: $1.83 per serving
• Caffeine Content: 350 mg
• Other Stimulants: 100 mg (theobromine)
• Clinically Dosed Ingredients: Yes
• Artificial Additives: None

Product Review:

Bulk Black is the newest edition to the Transparent Labs pre-workout lineup. It’s the high-stim counter to their stim-free pre-workout. This pre-workout has a total of 450 mg of stimulants per serving, split up between 350 mg of caffeine and 100 mg of theobromine. 

But despite being high-stim, this pre-workout also has other ingredients, making for a balanced and effective formula that delivers the energy jolt as well as long-lasting energy to support your performance during long and intense workouts.

The other active ingredients in this formula are citrulline malate, beta-alanine, betaine, taurine, l-tyrosine, alpha-GPC, l-theanine, Senactiv®, and Bioperine®. 

Together, these compounds help enhance blood flow, improve endurance, boost power output, support focus and mental clarity, reduce fatigue, promote recovery, and increase nutrient absorption. Some of the ingredients also show promise in promoting muscle growth, recovery, and healthy testosterone levels.

Unlike many pre-workouts on the market, Bulk Black has clinical doses of all the ingredients on the label. This means the product contains the amounts of ingredients shown in scientific studies to be effective.

In my experience, Bulk Black hits quickly and provides a surge of energy. However, this energy boost doesn’t dissipate quickly. Instead, it keeps you energized for a long time, and the effects taper off gradually, instead of experiencing a sudden energy crash.

I also found that this pre-workout mixes well with water, doesn’t leave chunks, and doesn’t have a gritty texture. The taste is also pleasant, but there is a detectable sour note among all the flavors we’ve tested, including those intended to be sweet.

This pre-workout has no artificial colors or flavoring agents, similar to all other Transparent Labs products. Instead, it relies on natural ingredients like stevia extract. Each batch is third-party tested, and lab analyses are freely published on their website for everyone to see.

Highlights:

• At $1.83 per serving, Bulk Black is the perfect blend of quality, transparency, and affordability.

• All the active ingredients are clinically dosed. This means you get enough to experience the positive effects discussed in research papers.

• The product is free of artificial additives and flavoring agents.

• Bulk Black has two caffeine sources: caffeine from green coffee beans and dicaffeine malate, a caffeine form bound to malic acid. The 350 mg dose per serving comes from 275 mg caffeine and 75 mg Infinergy™ (Dicaffeine Malate).
  
  This combination of caffeine sources provides a quick energy release, as well as longer-lasting effects to help support your performance.

Drawbacks:

• The only real drawback of this product is that it has a lot of caffeine per serving, so it might be harder to integrate it into your day without exceeding the 400 mg daily limit recommended by the FDA.

Read our full review of Transparent Labs Bulk Black here.

2. Legion Pulse Pre-Workout

Key Features

• Price: $2.25 per serving
• Caffeine Content: 350 mg
• Other Stimulants: No
• Clinically Dosed Ingredients: Yes
• Artificial Additives: None

Product Review:

Legion is known for producing natural and science-based sports supplements, and things are no different regarding Pulse. This pre-workout uses a clinically-dosed and straightforward formula of citrulline malate, beta-alanine, betaine, l-theanine, caffeine, and alpha GPC. 

Being a high-stim formula, it has 350 mg of caffeine per two-scoop serving. Like Transparent Labs Bulk Black, Pulse has clinically effective doses of all ingredients, which means you get the active ingredients in the appropriate doses to deliver maximum benefits.

A two-scoop serving provides:

• 8 grams of citrulline malate
• 3.6 grams of beta-alanine
• 2.5 grams of betaine
• 350 mg of L-theanine
• 300 mg of alpha-GPC

Something many pre-workouts miss is L-theanine, an amino acid that fits well into high-stim formulas. This compound helps promote calmness and focus without causing drowsiness. 

It works well in combination with caffeine and alpha GPC by supporting concentration and helping to offset some of the potential side-effects of high stimulant doses––namely, anxiety and jitteriness. As a result, you feel energized, focused, and confident to attack each workout hard.

Another huge benefit is that Legion Pulse is third-party tested by Labdoor, a company widely regarded as the gold standard for independent third-party supplement testing. This means the product undergoes testing to ensure it has the listed ingredients in the appropriate doses and without potentially harmful compounds.

Lastly, Pulse has a good taste and mixes well with water. I didn’t find it to have a bitter or sour taste that is common with other pre-workout products.

While great overall, Legion has one drawback––its price. It costs $2.25 per serving, which is $0.64 more expensive than the average pre-workout supplement serving on the US market. That said, you can subscribe (get a pre-workout every 30 days) and save 10%.

Highlights:

• All active ingredients are clinically dosed. This means you get an adequate dose of each compound, ensuring maximum effectiveness.

• While Pulse is a high-stim pre-workout, it doesn’t solely rely on stimulants to deliver benefits. It also has non-stimulant ingredients like citrulline malate and beta-alanine that have been shown to boost exercise performance. So, even if you’ve built up a tolerance to caffeine, Pulse will still improve your gym performance.

• This product is third-party tested by Labdoor, a company with an excellent reputation in the industry.

• Legion offers excellent customer service and readily responds to any customer concerns. You also get free shipping within the US, and they have a non-judgmental money-back guarantee on all their products.

Drawbacks:

• The biggest drawback of Pulse is the cost. At $2.25 per serving, it comes out $0.64 more expensive than the cost per serving of your average pre-workout on the US market. 

Read our full review of Legion Pulse here.

3. Ryse Godzilla Pre-Workout

Key Features

• Price: $2.84 per whole serving (two scoops)
• Caffeine Content: 400 mg
• Other Stimulants: 100 mg (theobromine)
• Clinically Dosed Ingredients: Yes
• Artificial Additives: Yes (artificial sweeteners)

Product Review:

Ryse Godzilla is third on my list of recommended high-stim formulas. It has one of the biggest serving sizes, roughly 30 grams of active ingredients per full serving (two scoops). It has:

• 11 grams of citrulline (nine grams of citrulline malate and two grams of citrulline nitrate)
• 6.4 grams of beta-alanine
• 5 grams of betaine
• 5 grams of creatine monohydrate
• 400 mg of caffeine (350 mg of caffeine anhydrous and 50 mg of extended-release caffeine)

These doses meet (and, in some cases, exceed) clinical doses, which means you get enough of each active ingredient to experience the benefits. 

I sometimes even take one scoop (half a serving) and still get a good amount of each active ingredient: 5.5 grams of citrulline, 3.2 grams of beta-alanine, 2.5 grams of betaine, 2.5 grams of creatine, and 200 mg of caffeine. 

Something that sets this pre-workout apart from many competitors is that it offers two types of caffeine: one that releases quickly and provides a sudden boost of energy, and another that releases more gradually, leading to long-lasting energy to support even longer and more demanding workouts.

Now, while a worthy competitor to Bulk Black and Pulse, Godzilla has some drawbacks. 

First, this pre-workout has a dairy-based ingredient: hydrolyzed casein tripeptides as VasoDrive-AP® (300 mg per full serving). This means Godzilla might not be ideal if you have a dairy allergy or intolerance. 

Something worth mentioning is that this pre-workout is known to cause stomach discomfort in some users, as seen in Amazon reviews. For example, one customer wrote, “This is a decent pre-work out. The ingredients are ok. I will say, though, that my stomach doesn’t like something.”

I’ve tested the product without noticing any stomach discomfort, but this is still something to remember. 

Another potential downside is that it includes 5g of creatine per serving, a great ingredient, but one that doesn’t need to be taken pre-workout. It’s not the end of the world, but I prefer to take creatine after dinner, given that it doesn’t offer any immediate performance-boosting benefits, and its effectiveness relies on a consistent intake.

To conclude, Ryse Godzilla was a pleasant surprise and a step up from the Ryse Loaded Pre.

It provides long-lasting energy and a performance boost without making me feel jittery. I also never experienced an energy crash, which can be somewhat common with high-stim pre-workout formulas.

That said, it might be best to start with less than the recommended two-scoop serving to see how this product feels and if it sits well in your stomach, especially given that two scoops provide 400 mg of caffeine, the daily upper limit recommended by the FDA. 

For instance, start with one scoop and gradually work up to 1.5 scoops, leaving the full two-scoop serving for days where you need the extra push to complete your most demanding workouts. 

Highlights:

• You get clinical or beyond clinical doses for almost all active ingredients. Theobromine is one exception because there’s currently no clinically established dose, given how different people’s responses are.

• Ryse Godzilla has several patented ingredients: NO3-T® (Citrulline nitrate), zumXR® (extended release caffeine), Cognizin® (citicoline), and VasoDrive-AP® (Hydrolyzed casein). Such ingredients often undergo clinical trials to ensure their safety and effectiveness.

• The official serving size is two scoops, but the cool thing about this pre-workout is that you still get high amounts of the active ingredients in a single scoop. This means you can adjust your caffeine intake (say, you’ve already had a couple of coffee drinks today and don’t want to overdo it) and reduce your cost per serving to make the tub last longer.

Drawbacks:

• At $2.84 per whole serving, Ryse Godzilla can get expensive. That said, you generally shouldn’t take a full two scoops before every workout, and should take one to one-and-a-quarter scoops, which would put you around the average cost per serving of $1.61.

• Some users have reported feeling stomach discomfort and needing to visit the bathroom around 90 minutes after taking this product. While I didn’t experience this myself, it’s something to consider.

• If you take the full two scoops, you should not consume any other caffeine products within the same day: coffee, tea, energy drinks, sports drinks, and such.

Read our full review of Ryse Godzilla here.

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