Blue Raspberry
Bulk Black Pre-Workout
Best Seller

Bulk Black Pre-Workout

The pinnacle of a clinically dosed pre-workout supplement for stim lovers that demand the most from their training.

No Artificial Sweeteners

No Artificial Sweeteners

Gluten-Free and Non-GMO

Gluten-Free and Non-GMO

No Artificial Coloring

No Artificial Coloring

No Artificial Preservatives

No Artificial Preservatives

8 Flavors Available:

Third-Party Testing

We believe trust is earned through transparency. That’s why we provide full access to our third-party test results, so you can feel confident in what you’re taking. View all third-party tests.

Transparent Labs Bulk Black is the pinnacle of a clinically dosed pre-workout supplement for stim lovers. If you have experience with our regular Bulk Pre-Workout formula but want some extra "pep" in your step, this is the pre-workout for you. Each scoop of Bulk Black packs over 17 grams of proven nitric oxide boosters, hard-hitting nootropics, natural testosterone-supporting ingredients, and muscle fortifiers dosed according to scientific evidence, so you can bring the noise every time you walk into the gym.


Like all Transparent Labs pre-workout formulas, Bulk Black contains absolutely no artificial sweeteners, flavors, food dyes, or added sugars.

Blue Raspberry

Orders in the US over $99 ship free.

Once your order has shipped out from our fulfillment center, you will receive a Shipping Confirmation email. If you selected a tracked shipping method, you will receive your tracking information, along with the necessary steps to track your order, within this email. Please note, orders are generally fulfilled same day or next business day.

Click here for the full shipping and delivery guide »

45 Day Satisfaction Guarantee

If you are not satisfied with your product, we will offer you a full refund or store credit for the value of the item within 45 days of delivery.

Click here for the full refund policy »

why use Bulk Black Pre-Workout?

Transparent Labs Bulk Black Pre-Workout provides clinically effective doses of evidence-based ingredients to help you crush every training session.

Improve Strength and Build Muscle

Bulk Black Pre-Workout is formulated for dedicated gym-goers and athletes training to build muscle and strength.

Improve Strength and Build Muscle

Ignite Focus and Energy

Get dialed in for every workout with ample doses of key nootropics like AlphaSize® alpha-GPC, PurCaf®, Infinergy™, L-tyrosine, and L-theanine.

Ignite Focus and Energy

Maximize Blood Flow

The nitric oxide boosters in BULK BLACK Pre-Workout rapidly increase blood flow to skeletal muscles so you can achieve full muscle pumps every time you train.

Maximize Blood Flow

Volumize Muscle Cells

Bulk Black Pre-Workout provides essential electrolytes and vitamins along with osmolytes to ensure muscle cells stay hydrated throughout your workout.

Volumize Muscle Cells

Key Ingredients

Our formulas are made with clean, natural ingredients, with clinically-validated dosages to support health and performance.

L-Citrulline Malate (2:1)

8,000 mg

L-citrulline is a renowned nitric oxide booster found naturally in watermelon and gets your blood flowing in the gym.

L-Citrulline Malate (2:1)

Beta-Alanine

4,000 mg

Beta-alanine allows you to push yourself longer and harder in the gym by increasing muscle carnosine levels.

Beta-Alanine

BetaPure™ Betaine Anhydrous

2,500 mg

Betaine (trimethylglycine) is a natural constituent of sugar beets that helps regulate cellular fluid balance and blood flow.

BetaPure™ Betaine Anhydrous

Taurine

1,300 mg

Taurine is an amino acid with numerous ergogenic properties.

Taurine

L-Citrulline Malate (2:1)

8,000 mg

L-citrulline is an amino acid naturally found in watermelon that plays an important role in kidney function. It's become a popular ingredient in pre-workout supplements due to its ability to boost nitric oxide levels [1]. 

When nitric oxide production increases, blood flow improves, allowing nutrients and oxygen to replenish muscle tissue more efficiently. Ultimately, this translates to greater muscle pumps and heightened energy levels.

Numerous studies have demonstrated the ergogenic effects of L-citrulline malate, the citrulline salt of malic acid, such as:

  • Improving strength, aerobic performance, and muscle endurance [2, 3]

  • Elevating nitric oxide levels even more than equivalent doses of L-arginine [4]

Enhancing muscle anabolism and reducing muscle catabolism [5]

L-Citrulline Malate (2:1)

Beta-Alanine

4,000 mg

Beta-alanine is a beta-amino acid that combines with L-histidine to form the dipeptide carnosine. Supplementing with beta-alanine has been shown to increase muscle carnosine levels, which are quickly depleted during intense exercise [6].

Carnosine is an endogenous dipeptide that functions as a buffer in muscle cells, thereby attenuating the accumulation of acidic byproducts of muscular exertion (e.g., lactate and hydrogen ions) [7].

Each scoop of LEAN Pre-Workout provides an evidence-based dose of beta-alanine (2,000 mg) to confer a range of benefits, such as:

  • Delaying the onset of neuromuscular fatigue during intense exercise [8]
  • Increasing overall muscle strength [9]
  • Improving muscle endurance and total work capacity [10]
  • Reducing and combatting the formation of dysfunctional proteins and promoting the formation of healthy proteins [11]

Significantly increasing lean muscle mass as part of a diligent resistance-training program [12]

Beta-Alanine

BetaPure™ Betaine Anhydrous

2,500 mg

Betaine, also known as trimethylglycine, is a naturally occurring metabolite that serves as a methyl donor and osmolyte in the body. Though the mechanisms are not entirely understood, betaine supplementation has shown promise in enhancing power output and, to a lesser extent, endurance capacity in athletes [13, 14, 15].

 It is plausible that betaine supplementation promotes athletic performance by maintaining cellular hydration and reducing homocysteine levels, thereby encouraging healthy cardiovascular function and blood flow [16].

BetaPure™ Betaine Anhydrous

Taurine

1,300 mg

Taurine is another staple pre-workout ingredient with diverse benefits for athletes and gym-goers. For one, taurine is a potent nootropic that confers synergy with caffeine to promote focus and reduce brain cell inflammation and oxidative stress [17, 18]. 

Taurine can also enhance physical performance via increased blood flow to skeletal muscle tissue [19, 20]. Greater blood flow to muscle tissue encourages a favorable milieu for muscle function and recovery during training. Additionally, taurine supplementation has been shown to improve performance in endurance athletes [21].

Taurine

L-Tyrosine

1,000 mg

L-tyrosine is a conditionally essential amino acid that serves as a precursor to dopamine and norepinephrine, two neurotransmitters that govern motivation and reward. Research shows that supplementing with L-tyrosine can significantly enhance cognitive performance, especially under acutely stressful situations (such as intense training) [22].

L-Tyrosine has also been shown to improve “cognitive flexibility,” meaning it can help you adapt to changing cognitive demands without letting extraneous thoughts take over [23].

L-Tyrosine

Alpha-GPC

300 mg

Alpha-GPC (glycerylphosphorylcholine) is a popular nootropic supplement and a bioavailable source of choline, an essential micronutrient for cholinergic transmission and, by extension, cognitive function. Alpha-GPC is primarily found in the brain and is one of the two major storage forms of choline in the cytosol (interior space of cells), along with phosphocholine [24].

This ingredient can enhance physical and mental performance by increasing acetylcholine and growth hormone production [25, 26, 27]. The former is important for focus and mental acuity, while the latter promotes fatty acid oxidation and reduces muscle tissue breakdown. As such, alpha-GPC (as patented AlphaSize®) is one of the key ingredients in Bulk Pre-Workout.

Alpha-GPC

PurCaf® Organic Caffeine + Infinergy™ Di-Caffeine Malate

350 mg

While most pre-workouts contain synthetic caffeine anhydrous, we formulated BULK BLACK Pre-Workout with organic caffeine derived from green coffee beans (as PurCaf®) and sustained-release Infinergy™ (di-caffeine malate). 

On the molecular level, caffeine (chemically known as 1,3,7-trimethylxanthine) is an alkaline, organic substance derived from xanthine — a biologically important purine base found in many bodily tissues and fluids. 

Methylxanthines like caffeine and theobromine stimulate the central nervous system (CNS) and heart to promote wakefulness and motivation.

Numerous studies have shown that taking caffeine before exercise can significantly improve overall performance, largely by reducing the rate of perceived exertion [28]. Caffeine may also enhance endurance and strength by increasing fatty acid oxidation and sparing muscle glycogen [29].

PurCaf® Organic Caffeine + Infinergy™ Di-Caffeine Malate

L-Theanine

200 mg

L-theanine is an isomer of the amino acids L-glutamate and L-glutamine. It was discovered centuries ago as one of the primary amino acids in green tea leaves and is also found in various mushroom species.

L-theanine is highly bioavailable when taken orally and actively traverses the blood-brain barrier to enhance mental acuity and attenuate stress [30, 31]. Its nootropic effects are appropriately described as "alert relaxation," which is to say it promotes a sense of calmness while improving focus. 

L-theanine can also help take the edge off of stimulants, particularly caffeine. In fact, research shows that pairing L-theanine with caffeine creates a nootropic synergy that bolsters cognitive function and alertness more effectively than taking either nootropic on its own [32].

L-Theanine

Theobromine

100 mg

Theobromine is the primary alkaloid found in cocoa beans and is chemically related to caffeine, acting as a phosphodiesterase inhibitor and central nervous system stimulant [33].

Research has found that theobromine has differential contributions to mood and cognitive function compared to caffeine, providing further insight into the distinct yet synergistic nature of these naturally occurring stimulants [34].

Theobromine

SenActiv®

50 mg

The adaptogens that comprise SenActiv® are Panax notoginseng root and rose hips (Rosa roxburghii). The notoginseng in SenActiv® is highly concentrated in notoginsenoside R1, a beneficial compound that helps accelerate muscle recovery during/after intense exercise. 

Likewise, the rose hips provide several ginsenoside-like molecules that confer synergistic recovery-enhancing effects with ginsenoside R1 [35]. 

These phytonutrients are suggested to work by bolstering a cellular "cleaning" process known as autophagy, particularly in skeletal muscle cells [36, 37, 38].

SenActiv®

BioPerine®

5 mg

BioPerine® is a patented black pepper (Piper nigrum) fruit extract standardized for its piperine content. Piperine is a natural alkaloid known for its “bioenhancer” properties, improving the bioavailability of molecules that are typically poorly absorbed or extensively metabolized in the liver [39, 40]. 

Hence, BioPerine® helps your body better absorb and utilize the other active ingredients in Bulk Pre-Workout.

BioPerine®

Boron Citrate

3 mg

Boron is an important trace mineral with numerous roles in the human body. Recent evidence suggests that men who supplement with boron daily have higher levels of testosterone and lower levels of estradiol (estrogen) than those who don’t [41].

Boron Citrate

Zinc Chelate

10 mg

Chelated zinc is a bioavailable source of zinc, an essential cofactor for various enzymes. Research suggests zinc is crucial for supporting fertility and sperm cell counts in men [42]. This is largely because zinc aids in natural testosterone production, and males who are zinc deficient are at a higher risk of infertility [43].

Zinc Chelate

Vitamins B6 and B12

5 mg and 100 mcg

Vitamins, as a collective group, are essential micronutrients that act as coenzymes (read: "helper molecules") for enzymes throughout the body. Vitamins B6 and B12 are water-soluble vitamins that are particularly important for cognitive function, cardiovascular health, nutrient metabolism, and immunity [44, 45]. As such, you can't go wrong with having these in your pre-workout arsenal.

Vitamins B6 and B12

Sodium and Potassium

180 mg and 125 mg

Many minerals act as electrolytes in aqueous solutions, meaning they carry an electric charge that influences concentration gradients across cellular membranes and enzyme functions. Sodium and potassium are arguably the most important electrolyte minerals, being well-known to impact hydration status and exercise performance  [46].

Sodium and Potassium

Complete Your Stack

Pair Bulk Black Pre-Workout with these products for a complete foundational stack.
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Every Ingredient Matters To Make Every Effort Count.

Customer Reviews

Based on 789 reviews
79%
(626)
9%
(68)
7%
(55)
3%
(23)
2%
(17)
Y
Yanira Hanoumis
Works Great!

Gives a good boost of energy and have great focus when working out. The only thing I would change is the scoop size. Other preworkout have a scoop half the size of this one.

A
Arjunsingh Panwar

Mix well and all ingredients are transparent

M
Max Zakharenko
Really good

better than any others i tried

D
Drew Adkins
Unlike all the others

I’ve taken a lot of other preworkouts but this is unlike anything I’ve taken. I have great workouts and don’t feel jittery or a crash after. I guess that’s what clean ingredients will do for you 💪 plus I really enjoy the taste!

J
Juan knauss
Best stuff out in

Super powerful

How to Use

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Step 1 - Add Powder

Beginners: To assess your tolerance, add 1/2 scoop (included in the container) of bulk black pre-workout into a shaker cup with 6-8 ounces of cold water or your preferred beverage. Experienced Users: Add 1 level scoop (included in the container) of bulk black pre-workout into a shaker cup with 10-12 ounces of cold water or your preferred beverage. If the effects feel subtle, increase to a full scoop before the next workout.
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Step 2 - Mix Thoroughly

Place the lid securely on your shaker cup and shake vigorously until the powder fully dissolves and the mix is smooth.
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Step 3 - Consume

For best results, consume bulk black pre workout 20-30 minutes before your workout (ideally on an empty stomach or at least 90 minutes after a meal).
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Step 4 - Use on Training Days

Take bulk black pre-workout before workouts on days you train.

Disclaimer: This product contains caffeine; do not exceed one serving of BULK BLACK per day, and monitor your caffeine intake from all sources.

Frequently Asked
Questions

How much caffeine does bulk black pre-workout have?

Each serving of bulk black pre-workout contains 350 mg of caffeine from organic green coffee beans and Infinergy™ di-caffeine malate.

Can I take bulk pre-workout on non-training days?

Yes, you can take bulk black pre workout on non-training days if you want an energy boost. However, remember that this product contains caffeine and may cause restlessness if taken within 5 hours of bedtime.

Can i take bulk black pre-workout if i am subjected to drug testing for my sport?

Yes, absolutely. Transparent Labs bulk black pre-workout contains zero banned substances and is Informed Choice certified for athletes.

What is the difference between transparent labs bulk black and bulk pre-workouts?

Bulk Pre-Workout is designed to support lean muscle growth and includes testosterone-supporting micronutrients, while BULK BLACK is a” harder hitting” version of BULK due to the extra caffeine and nootropic contents.

Why doesn't bulk black pre-workout contain creatine?

Large doses of caffeine may interfere with the ergogenic effects of creatine [34]; since bulk pre-workout contains caffeine, we decided to keep the creatine separate.

How much caffeine does bulk black pre-workout have?

Each serving of bulk black pre-workout contains 350 mg of caffeine from organic green coffee beans and Infinergy™ di-caffeine malate.

Can I take bulk pre-workout on non-training days?

Yes, you can take bulk black pre workout on non-training days if you want an energy boost. However, remember that this product contains caffeine and may cause restlessness if taken within 5 hours of bedtime.

Can i take bulk black pre-workout if i am subjected to drug testing for my sport?

Yes, absolutely. Transparent Labs bulk black pre-workout contains zero banned substances and is Informed Choice certified for athletes.

What is the difference between transparent labs bulk black and bulk pre-workouts?

Bulk Pre-Workout is designed to support lean muscle growth and includes testosterone-supporting micronutrients, while BULK BLACK is a” harder hitting” version of BULK due to the extra caffeine and nootropic contents.

Why doesn't bulk black pre-workout contain creatine?

Large doses of caffeine may interfere with the ergogenic effects of creatine [34]; since bulk pre-workout contains caffeine, we decided to keep the creatine separate.